Operative Otorhinolaryngology

EDITED BY

N I G E LB L E A C H

MB, ChB, FRCS(Otol), FCSHK Consultant Otolaryngologist Heatherwood and Wexham Park Hospitals NHS Trust Wexham, Slough, Berks, UK

C H R I S R/11ILFORD BSc, FRCS Consultant Otolaryngologist Department of Otorhinolaryngology The Radcliffe Infirmary, Oxford, UK

ANDREW VAN HASSELT MBChB, FCS(SA), FRCS(Edin), FHKCORL, FHKAM(Otol), MMed(Oto1) Professor of Surgery, Chief of Otorhinolaryngology The Chinese University of Hong Kong Prince of Wales Hospital Hong Kong

FOREWORD BY

ALAN KERR

b

Blackwell Science

0 1997 by Blackwell Science Ltd Editorial Offices: Osney Mead, Oxford OX2 OEL 25 John Street, London WC1N 2BL 23 Ainslie Place, Edinburgh EH3 6AJ 350 Main Street, Malden MA 02148 5018, USA 54 University Street, Carlton Victoria 3053, Australia Other Editorial Offices: Blackwell Wissenschafts-Verlag GmbH Kurfiirstendamm 57 10707 Berlin, Germany Zehetnergasse 6 A-1140 Wien, Austria All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the copyright owner First published 1997 Set by Excel Typesetters, Hong Kong Printed and bound in Great Britain by the Bath Press, Bath The Blackwell Science logo is a trade mark of Blackwell Science Ltd, registered at the United Kingdom Trade Marks Registry

A catalogue record for this title is available from the British Library ISBN 0-632-03747-4 Library of Congress Cataloging-in-Publication Data Operative otorhinolaryngology I edited by Nigel Bleach, Chris Milford, Andrew van Hasselt. p. cm. Includes bibliographical references and index. ISBN 0-632-03747-4 1. Otolaryngology, Operative. I. Bleach, Nigel. 11. Milford, Chris. 111. Van Hasselt, Andrew. [DNLM: 1. Otorhinolaryngologic Diseases-surgery. WV 168061 19971 RF51.0615 1997 617.5’1’059-dc20 DNLM/DLC for Library of Congress 95-47084 CIP

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9 Myringoplasty, 44 Peter-John Wormald

List of Contributors, ix Foreword, xiii

10 Ossiculoplasty, 52 Antony A. Narula

Preface, xv

11 Stapedectomy, 56 Tony Wright

List of Abbreviations, xvii

1 Aspects of General Anaesthesia for ENT Surgery, 1 John R. Lehane

12 Mastoid Surgery, 65 John P. Birchall 13 Surgery of the Discharging Mastoid, 76 Andrew van Hasselt

2 Surgical Outcome Analysis and Audit, 6 Rowena M. Ryan

14 Osseo-integrated Implants, 80 Michael P.Rothera

Section I : Otology (External Ear, Middle Ear and Mastoid)

15 CochlearImplantation, 85 P.Gerard Reilly and Gerard M. O’Donoghue

3 Excision of Lesions of the Pinna, 13 Michael C.F. Tong and Ashraf Zekri

Section 2: Otoneurosurgery and Skull 6ase Surgery

4 Excision of Preauricular Sinus, 18 Hoo-Kwong Leong

5 Excision of Canal Osteomas and Exostoses, 21 Kevin J . Feely

16 Approaches to the Internal Auditory Canal Cerebellopontine Angle, 93 Robert J.S. Briggs

6 Meatoplasty, 25 Robert E. Quiney

17 Surgery of the Facial Nerve, 107 Glen R. Croxson

7TympanostomyTubeInsertion, Peter J.Rob6

32

and

18 Surgery for Vertigo, 120 Michael J . Gleeson and Ben Pahtixxa 19 Approaches to theInfratempora .l Fossa, 137 Tristram H.J. Lesser

8 Approaches to the Middle Ear and Mastoid, 38 Robin Youngs V

vi

Contents

20 Surgery of Glomus Tumours of the Temporal Bone, 14.5

Chris A. Milford 21 Petrosectorny, 1S4 Tristram H.]. Lesser

Section 3: Rhinology

3.5 Surgery for Cerebrospinal-fluid Rhinorrhoea, 249

Chris A. Milford 36 Surgery for Epistaxis, 2.56 John K.S. Woo

Section 4: Endoscopy

22 Surgical Correction of Nasal Fractures, 161 Rodney E. Mountain

37 Nasopharyngoscopy,265 John K.S. Woo

23 Maxillary Sinus Lavage and Inferior Meatal Antrostomy, 16.5

3 8 Pharyngolaryngoscopy and Rigid Oesophagoscopy (including Panendoscopy), 269

John M . Hadley

Simon A. Hickey

24 Surgical Reduction of the Inferior Turbinates, 169 Paul 0 'Flynn

39 Flexible Oesophagoscopy, 276 Charles S. Robertson

2.5 Septoplasty and Repair of Septal Perforation, 173

40 Rigid Bronchoscopy, 280

Victor Abdullah

Charles A. East 26 Rhinoplasty and Septorhinoplasty, 182 Nick S. Jones 27 Functional Endoscopic Sinus Surgery, 193 Vij'ayK. Anand and Mark J. Glasgold

41 Assessment of the Paediatric Airway: Laryngotracheobronchoscopy, 28.5

David Albert

Section 5: The Oral Cavity, Pharynx and Larynx

28 Surgery for Choana1 Atresia, 204 David W. Morgan

42 Adenoidectomy and Tonsillectomy, 295

29 External Operations on the Frontoethmoidal Complex, 208

43 ~vulopalatopharyngoplasty,301 Grant J.E.M. Bates

Peter M . Clarke

ValerieJ. Lund 30 Midfacial Degloving, 216

Valerie J.Lund 31 LateralRhinotomy and Medial Maxillectomy, 220

44 Surgery for Benign Lesions of the Oral Cavity, 308

Robert M.Sudderick 45 Phonosurgery and Microlaryngeal Surgery, 3 1S

Meredydd Harries and Murray Morrison

Nigel R. Bleach 46 Tracheostomy, 326 32 Maxillectomy and Maxillary Swing, 226 Willimn I. Wei 33 Anterior Craniofacial Resection, 233 Robert ].S. Briggs 34 Trans-sphenoidalHypophysectomy, 242

Alan P.Johnson

Victor Abdullah 47 Surgery of Paediatric Laryngotracheal Stenosis, 332

David Albert 48 Surgery of Hypopharyngeal Diverticula, 342 Alexander C. Vlantis

Contents 49 Surgery for Malignant Lesions of the Tongue, Floor of the Mouth and Alveolus, 349

vii

59 Branchial Cysts, Sinuses and Fistulae, 424 Robert W.T. Slack

Nicholas D. Stafford 50 Surgery for Malignant Lesions of the Oropharynx, 357 John Waldron 51 Total Laryngectomy, 365 R. Theo Gregor

60 Thyroid Surgery, 428 Nicholas P. McIuor 61 Surgery of the Parotid Gland, 436

John C. Watkinson

62 Radical and Conservative Neck Dissections, 444

Andrew C. Urquhart

52 Vertical Partial Laryngectomy, 373

Kerry D. Olsen

63 Surgery for Parapharyngeal-space Tumours, 454 Keith J. Dauidge-Pitts

53 Horizontal (Supraglottic) Laryngectomy, 3 83

R. The0 Gregor 54 Pharyngolaryngectomy and Pharyngolaryngooesophagectomy, 3 87 Christopher F. Perry 55

Surgical Voice Restoration, 396

Nigel R. Bleach and Andrew J.G. Batch

Section 6: The Neck, Thyroid and Major Salivary Glands 56 Lymph-node Biopsy in the Head and Neck, 409 Philip J. Robinson

57 Surgery of the Submandibular and Minor Salivary Glands, 4 15 Christopher A. Joseph 58 Excision of Thyroglossal Cysts, 420

D. Gareth John

64 Deep-neck-space Infection, 462 Graham J. Cox and Bippon C. Vinayak

Section 7: Plastic and Reconstructive Surgery 65 Pinnaplasty, 471

Chris J. Inglefield 66 Facial Reconstruction with Local Cutaneous Flaps, 476 Keith W. Cullen and Ian W.R. Holten

67 Principles of Head and Neck Reconstruction, 489 Timothy E.E. Goodacre Index, 505

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VICTOR ABDULLAH BSc, FRCS, FCS(HK), FHKCORL,

Otolaryngology, Southampton University Hospitals, Tremona Road, Southampton, UK

FHKAM(OtoL), Senior Medical Officer, Division o f Otorhinolaryngology, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong

GRAHAM J. COX MBBS, BDS, FRCS, Consultant Otolaryngologist, Department of Otolaryngology, Stoke Mandeville Hospital NHS Trust, Aylesbury, Bucks, UK

DAVID ALBERT FRCS, Paediatric Otolaryngologist,

GLEN R. CROXSON MBBS, FRACS, Visiting Medical

Hospital for Sick Children, Great Ormond Street, London, UK

Officer, Suite 407, Royal Prince Alfred Hospital, 100 Carillon Avenue, Newtown, Australia

VIJAY K. ANAND MD, FACS, Surgeon Director,

KEITH W. CULLEN BSc, FRCS(Ed), Consultant Plastic and

Department of Otolaryngology, Manhattan Eye Ear and Throat Hospital, New York, USA

Reconstructive Surgeon, The Queen Victoria Hospital, East Grinstead, West Sussex, U K

ANDREW J.G. BATCH BSc, FRCS, FRCS(ENT),

KEITH J.DAVIDGE-PITTS MB, BCh, FRCS(Edin),

Consultant ENT Surgeon, City Hospital NHS Trust, Dudley Road, Birmingham, UK

FCS(SA), FACS, Ear Nose and Throat Surgeon, Morningside Clinic, Rivonia and Hill Roads, Sandton, South Africa

GRANT J. BATES BSc, BM, BCh, FRCS, Consultant

CHARLES A. EAST FRCS, Consultant ENT Surgeon, Royal

Otolaryngologist, Department of Otorhinolaryngology, The Radcliffe Infirmary, Oxford, UK

National Throat Nose and Ear Hospital, Gray’s Inn Road, London, UK

JOHN P. BIRCHALL MD, FRCS, Professor o f

KEVIN J. FEELY MB, BS(Qld), FRACS, Consultant

Otorhinolaryngology, Department of Otorhinolaryngology, Queen’s Medical Centre, Nottingham, UK

Otolaryngologist, Head and Neck Surgeon, Mater Medical Center, JessieStreet, Rockhampton, Australia

NIGEL R. BLEACH MB, ChB, FRCS(Otol), FCSHK,

MARK J. GLASGOLD MD, Clinical Assistant Professor,

Consultant Otolaryngologist, Heatherwood and Wexham Park Hospitals NHS Trust, Wexham, Slough, Berks, UK

Division of Otolaryngology, Head and Neck Surgery, Robert Wood Johnson Medical School, New Jersey, USA

ROBERT J.S. BRIGGS MBBS, FRACS, Diplomat American

MICHAEL J. GLEESON MD, FRCS, Professor of

Board of Otolaryngology and Senior Lecturer, Melbourne University, Department of Otolaryngology, Melbourne, Australia

Otolaryngology, Department of Otolaryngology and Skull Base Surgery, Guy’s Hospital (UMDS), and Skull Base Surgeon to Guy’s, King’s and St Thomas’s Hospitals, London, UK

PETER M. CLARKE BSc, FRCS(ORL), Senior Registrar in

ix

x

List of Contributors

TIMOTHY E.E. GOODACRE BSc, FRCS, Consultant Plastic Surgeon, Department of Plastic and Reconstructive Surgery, The Radcliffe Infirmary, Oxford, UK

R. T H E 0 GREGOR MB, BCh, PhD, FRCS, FACS, Professor and Head of Department of Otorhinolaryngology, University of Stellenbosch and Chief Otolaryngologist, Tygerberg Hospital, Tygerberg, South Africa

JOHN M. HADLEY MA, FRCS, FRCS(Orl), Consultant ENT Surgeon, West Middlesex University Hospital NHS Trust, Isleworth, Middlesex, UK

MEREDYDD HARRIES BSc, MBBS, FRCS, Consultant ENT Surgeon, The Royal Sussex County Hospital, Eastern Road, Brighton, UK

SIMON A. HICKEY MA, BM, BCh, FRCS, Consultant ENT Surgeon, Torbay Hospital, Lawes Bridge, Torguay, Devon, UK

IAN W.R. HOLTEN MBBS, FRCS, Registrar in Plastic Surgery, Department of Plastic Surgery, Queen MaryS University Hospital, Roehampton, London UK.

CHRIS J.INGLEFIELD BSc, FRCS, Senior Registrar in Plastic Surgery, Plastic Surgery Department, Wexham Park Hospital, Wexham, Slough, Berks, UK

D. GARETH JOHN BSc, MBBS, FRCS, Consultant ENT Surgeon, Department of ENT Surgery, Poole Hospital NHS Trust, Poole, UK

ALAN P. JOHNSON MB, ChB, FRCS, Consultant Otolaryngologist/Headand Neck Surgeon, Department of Otolaryngology, The Queen Elizabeth Hospital, Edgbaston, Birmingham, UK

NICK S. JONES BDS, FRCS, Consultant Otorhinolaryngologist, Departmentof Otorhinolaryngology, Queen’s Medical Centre, Nottingham, UK

CHRISTOPHER A. JOSEPH MB, BCh, FRCS, FCS,

MMED, ENT Surgeon, River Club, Gauteng, Johannesburg, South Africa

TRISTRAM H.J. LESSER MS, FRCS, Consultant ENT Surgeon, Department of Otorhinolaryngology/Headand Neck Surgery, Walton Hospital, Liverpool, UK

VALERIE J. LUND MS, FRCS, FRCS(Ed), Professor in Rhinology, Institute of Laryngology and Otology, Royal National Throat Nose and Ear Hospital, Gray’s Inn Road, London, UK

NICHOLAS P. McIVOR MBChB(Otago), FRCS(Ed), FRACS, Otolaryngologist/Headand Neck Surgeon, Green Lane Hospital, Auckland, New Zealand

CHRIS A. MILFORD BSc, FRCS, Consultant Otolaryngologist, Department of ~torhinolaryngology, The Radcliffe Infirmary, Oxford, UK

DAVID W. MORGAN BSc, M B , ChB, FRCS, FRCS(Otol), Consultant ENT Surgeon, ENT Department, Birmingham Heartlands Hospital, Bordesley Green, Birmingham, UK

MURRAY MORRISON MD, Professor and Head of Otolaryngology, Vancouver General Hospital, Vancouver, USA

RODNEY E. MOUNTAIN MB, ChB, FRCS(Ed), Consultant Otolaryngologist, Departmentof Otolaryngology, Ninewells Teaching Hospital, Dundee, UK

ANTONY A. NARULA MA, FRCS, Consultant Otolaryngologist, Departmentof ENT, Leicester Royal Infirmary, Leicester, UK

GERARD M. 07DONOGHUEMCh, FRCS, FRCSI, Consultant Otolaryngologist/SkullBase Surgeon, Department of Otolaryngology, Queen’s Medical Centre, Nottingham, UK

PAUL O’FLYNNE MBBS, FRCS, Consultant ENT Surgeon, The Royal National Throat Nose and Ear Hospital, Gray’s Inn Road, London, U K

KERRY D. OLSEN MD, Consultant, Department of Otorhinolaryngology, Mayo Clinic and Mayo Foundation, Professor of Otolaryngology, Mayo Medical School, Rochester, Minnesota, USA

JOHN R. LEHANE MB, ChB, MRCP(UK), FRCA, Consultant Anaesthetist, Nufield Departmentof Anaesthetics, The John Radcliffe, Headington, Oxford,UK

€300-KWONG LEONG MB, BS, FRCS, FAMS, Senior Lecturer and Consultant Otolaryngologist, Departmentof Otolaryngology, National University Hospital, Lower Kent Ridge Road, Singapore

BEN PANIZZA FRCS, Clinical Fellow to Department of Otolaryngology, Guy’s and St Thomas’s Hospital, London, UK

CHRISTOPHER F. PERRY MB, BS(Qld), DTM & H(L’pool), FRACS, Consultant Otolaryngologist/Headand Neck Surgeon, Watkins Medical Centre, Brisbane, Australia

List of Contributors ROBERT E. QUINEY FRCS, Consultant Otolaryngologist, Royal Free Hospital, London, U K

xi

BIPPON C. VINAYAK MBBS, FRCS, Clinical Lecturer in Otolaryngology, Department of Otorhinolaryngology, The Radcliffe Infirmary, Oxford, U K

P. GERARD REILLY BSc, FRCSEd(ORL), Consultant ENT Surgeon, York District Hospital, York, UK

PETER J. ROBB BSc, MB, FRCS, FRCS(Ed), Consultant Otolaryngologist and Clinical Director of Surgery, Epsom Healthcare NHS Trust, Epsom, Surrey, U K

CHARLES S. ROBERTSON MB, BS, DM, FRCS, Consultant General Surgeon, Worcester Royal Infirmary, Worcester, UK

PHILIP J. ROBINSON FRCS, FRCS( Otol), Consultant Otolaryngologist, Department of Otolaryngology, Southmead Hospital, Westbury on Trym, Bristol, U K

ALEXANDER C. VLANTIS MB, BCh, DA(SA), FCS(SA)ORL, Consultant ENT Surgeon, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong

JOHN WALDRON FRCS, Consultant ENT Surgeon, Royal United Hospital, Bath, U K

JOHN C. WATKINSON MSc, MS, FRCS, DLO, Consultant OtolaryngologistlHead and Neck Surgeon, Department of Otolaryngology, The Queen Elizabeth Hospital, Edgbaston, Birmingham, U K

WILLIAR/I: I. WE1 MBBS, MS, FRCS, DLO, FACS, Professor MICHAEL P. ROTHERA FRCS, Consultant ENT Surgeon, Department of Ear Nose and Throat Surgery, Hope Hospital, Salford, U K

of Otorhinolaryngology, Departmentof Surgery, The University of Hong Kong, Queen Mary Hospital, Hong Kong

JOHN K.S. WOO FRCS, DLO, Consultant ENT Surgeon, ROWENA M. RYAN MB, BCh, BAO, BA, FRCS, Consultant ENT Surgeon, Northwick Park and St Mark’s NHS Trust, Harrow, Middlesex, UK

ROBERT W.T. SLACK BSc, MB, ChB, FRCS, Consultant ENT Surgeon, Royal United Hospital, Bath, U K

NICHOLAS D. STAFFORD MB, ChB, FRCS, Professor of Otolaryngology and Head and Neck Surgery, Academic Department of Head and Neck Surgery and Otolaryngology, Hull Royal Infirmary, Hull, U K

Division of Otorhinolaryngology, Departmentof Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong

PETER-JOHN WORMALD FCS(SA)ORL, FRCS(Ed), Consultant Surgeon in Otolaryngology, Groote Schuur Hospital, Cape Town, South Africa

TONY WRIGHT LLM, DM, FRCS, Professor of Otolaryngology, Institute of Laryngology and Otology, Royal National Throat Nose and Ear Hospital, Gray’s Inn Road, London, U K

ROBERT M. SUDDERICK FDSRCS, FRCS, Consultant OtolaryngologistlHead and Neck Surgeon, Royal Surrey County Hospital, Guildford, Surrey, U K

MICHAEL C.F. TONG MB, ChB, DLO, FRCS, Senior Medical Officer and Honorary Lecturer, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong

ANDREW C. URQUHART MB, ChB, MMED, FCS(SA), FACS, ENT Surgeon, Department of Otolaryngology, Marshfield Clinic, Marshfield, Wisconsin, USA

ANDREW VAN HASSELT MBChB, FCS(SA), FRCS(Edin), FHKCORL, FHKAM(Otol), MMed(Otol), Professor of Surgery, Chief of Otorhinolaryngology, Department of Surgery, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong

ROBIN YOUNGS MD, FRCS, Consultant ENT Surgeon, West Suffolk Hospital, Bury St. Edmunds, Suffolk, UK

ASHRAF ZEKRI MS, FCPS(Fr), FHKCS, Consultant Plastic Surgeon, A1 Mataria Teaching Hospital, Cairo, Egypt and Visiting Associate Professor, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong

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Foreword

Examinations are a necessary evil and in Britain we seem to multiply these in a way that our surgical colleagues from other parts of the world find difficult to understand, but which some secretly envy. Given competent Higher Surgical Training in a satisfactory programme, this textbook shouldbe more than adequate to enable the candidate to pass the Intercollegiate Examination in Otolaryngology, either in its present form or in the modified form that is likely to appear in the next few years. In addition, the fact that this book has been written by young Otolaryngologists brings a freshness of approach that more than compensates for anylack of experience over time. This, again, should be helpful for those studying for this examination. Theinternationalnature of theproductionshould widen both the appeal of the book and the horizons of those who read it. I have no hesitation in offering my congratulations to the editors and contributors of this excellent book and commending it to all trainees, and others, in Otolaryngology.

I agree withthe editors that therehaslong been a need for a single volume textbook of Operative Otorhinolaryngology and I am delighted to be able to say that this need has now been fulfilled. The editors have been able to gather together many of the active, enthusiastic and progressive young surgeons currently in British Otolaryngology, and with the assistance of others from abroad, have produced a work of which they, and our specialty as a whole, can be proud. There already are some excellent textbooks of operative surgery available to our specialty but they do not meet the specifications that the editors haveset for themselves. Now, inone volume, thetrainee can see the whole of our specialty and get an understanding of all aspects of the surgery which we perform.There is a consistency of layout and illustration that makes foreasy reading. It is acknowledged that the more specialised textbooks willbe necessary forthemore specialised procedures, but then the trainee will not be attempting these duringthecourse of generalotolaryngology training.

Alan G. Kerr

xiii

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Preface

This volume was initially conceived from my dissatisfaction with the textbooksof operative ENT surgery available in the UK, in terms of their content, their outdated style of presentation and their high price for the trainee surgeon. A detailedplan of theproposedbookwas discussed initially with Andrew van Hasselt fromHong Kong and then with Chris Milford from Oxford, both of whom shared the same sentiments. Our purpose was to producea comprehensive, single volume textbook of OperativeOtorhinolaryngology, written by young surgeonsand with a continuity of style and artwork throughout. The book was to be aimed primarily at the trainee specialist surgeon in the UK, Australasia, Asia, India and Africa with authors to be drawn froma correspondingly widevariety of countries and institutions. It was also hoped that the book would be detailed enough to be a valuable and practical reference fortheyoungconsultantsurgeon.Theconcept was successfully presented to Blackwell Science, and the project slowly began to gather momentum. This book does not aim to compete with major subspecialist texts in Otoneurosurgery, Skull-Base Surgery, Head and Neck Surgery, Endoscopic Sinus Surgery or Facial Plastic Surgery. Nevertheless, basic and fundamental procedures within all these categories have been included, ashave chapters onAspects of General Anaes-

thesia in Otorhinolaryngology,Reconstruction in the Head and Neck,and Surgical Outcome Analysis and Audit. A standardised format for the operative procedures hasbeen adhered to as closely as possible throughout the text, although a minorityof chapters do notlend themselves to such strict criteria, in which case the format has been relaxed. The original operative diagrams have all been redrawn by a single artist, Mike Elms, in order to aid clarityand toimprove theoverall continuity of the book. By thesametoken,commonandnonspecific complications have not been repeated endlessly in the text, and standard medical abbreviations have been utilised as appropriate. As editors wehave tried, as far as possible, not to interfere with each contributing author's personal style and descriptive prose.Althoughthetechniques described, and opinions or recommendationsexpressed by the authorshave not always corresponded with thoseof the editors, we have not seen fit to alter the text radically, as there has been little of substance with which we have strongly disagreed. The result, we hope, is an informative and practical guide forENT surgeons that will contribute to the sound delivery of Operative Otorhinolaryngology. N.R.B.

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List of Abbreviations

A-P ABR ACHA ACTH AH1 AI AICA AIDS AJV BAHA BAAE BCC bd bid BIPP

anterior-posterior auditory brain-stem response air-conduction hearing-aid adrenocorticotrophic hormone apnoea-hypopnoea index apnoea index anterior inferior cerebellar artery acquired immunodeficiency syndrome anterior jugular vein bone-anchored hearing-aid bone-anchored artificial ear basal-cell carcinoma twice a day every two days bismuth, iodoform and paraffin paste

BNF

British National Formulary

BP CCA CFR CNS c02 CPA CPAP CSF CSOM CT dB DVT EAC EAM ECA ECG EMG EMLA ENG

blood pressure common carotid artery craniofacial resection central nervous system carbon dioxide cerebellopontine angle continuous positive airway pressure cerebrospinal fluid chronic suppurative otitis meatus computed tomography decibel deep vein thrombosis external auditory canal external auditory meatus external carotid artery electrocardiogram electromyographic eutectic mixture of local anaesthetic electronystagemography

ENOG ENT ESR ET EUA FESS FG FNAC FRC GA GI GP GSPN H 2 0 2

H20 HL HIV HPL IAC IAM ICA ID IgA IJV IM ITU iu IV IVC kHz KTP LA LAIJP LP0 LTB

xvii

electroneuronography ear, nose and throat erythrocyte sedimentation rate endotracheal tube examination under anaesthetic functional endoscopic sinus surgery french gauge fine-needle aspiration cytology functional residual capacity general anaesthetic gastrointestinal general practitioner greater superficial petrosal nerve hydrogen peroxide water hearing loss human immunodeficiency virus horizontal partial laryngectomy internal auditory canal internal auditory meatus internal carotid artery inferior dental immunoglobulin A internal jugular vein intramuscular intensive therapy unit international units intravenous inferior vena cava kilohertz potassium-titanyl phosphate local anaesthetic laser-assisted uvolopalatoplasty laryngopharyngo-oesophagectomy laryngotracheobronchoscopy

xviii

List of Abbreviations

LTS MCF MRI N,O NBM Nd-YAG NHS NSAID OME OPG Paco,

Pc02 PE PEG PET PICA P02

PORP PTA PTA PVC qds RBC rpm

laryngotracheal stenosis middle cranial fossa magnetic resonance imaging nitrous oxide nil by mouth neodynium-yttrium aluminium garnet National Health Service non-steroidal anti-inflammatory drug otorrhoea of the middle ear orthopantomogram partial pressure of arterial carbon dioxide partial pressure of carbon dioxide pharyngo-oesophageal percutaneous endoscopic gastrostomy positron emission tomography posterior inferior cerebellar artery partial pressure o f oxygen partial ossicular replacement prosthesis pure-tone audiogram pure-tone audiometry polyvinyl chloride four times a day red blood cells revolutions per minute

RNTNEH

RT SCC SMAS SMD SMR SOHND SRS SVR TB tds TE TEP TM TMJ TORP TPLO T s and As TSH TPLO UPPP URTI VT YAG

Royal National Throat, Nose and Ear Hospital radiotherapy squamous-cell carcinoma superficial musculo-aponeurotic system submucosal diathermy submucous resection supraomohyoid neck dissection slowreacting substance surgical voice restoration tuberculosis three times a day tracheo-oesophageal tracheo-oesophageal puncture tympanic membrane temporomandibular joint total ossicular replacement prosthesis total pharyngolaryngo-oesophagectomy tonsillectomy and adenoidectomy thyroid-stimulating hormone total pharyngolaryngo-oesophagectomy uvulopalatopharyngoplasty upper respiratory tract infection ventilation tube yttrium aluminium garnet

Aspects of General Anaesthesia for ENT Surgery J O H N R. LEHANE

very soluble and well buffered in the body, the arterial Pco, rises steadily at about 0.3kPa/min so that at 2min the Pco, will be 5.6 kPa. Within 3min hypoxaemia will cause cardiacarrestor severe braininjury while the change in Pco, remains unimportant. Now consider the effect of apnoea while breathing Respiratory gases 100Yo oxygen. While breathing oxygen the only gases in the alveoli The pathology requiring ENT surgery or the requireare oxygen, CO, and water vapour. The total pressure ments of the surgery itself mayseriously compromise the in the alveoli is 100 kPa (1atm). The partialpressure of patient’s airway. The important consequence of loss of water vapour is 6kPa and that of CO, is 5 kPa. The airwaypatency is hypoxaemiaand/orhypercapnia. balance, 89 kPa, must be the partial pressureof oxygen. While the pattern of blood -gas disturbance is influenced by the extent and rate After 2min of apnoeathe Pco, will rise by 0.6 to of onset of obstruction, itis critically dependent on the composition of the gas that 5.6 kPa so the alveolar Po, will have fallen to 88.4 kPa. After 30min of apnoea the alveolar Pco, will be 15 kPa the patient breathes. This may be air, 100% oxygen or mixtures of oxygen with nitrous oxide, air or helium. and the PO, 79 kPa. Thereis no hypoxia, although there is a respiratory acidosis. The total amount of oxygen stored in FRC and blood was only about 2.4L and yet Air versus oxygen therapy and the mitochondria will have consumed between 7 and prevention of hypoxaemia 1OL. In order to understand the circumstances where this apnoeic oxygenation fails it is necessary to know Anaesthesia increases the alveolar -arterial oxygen tenhow the additional oxygen is supplied. sion gradient and most patients would become During ventilation CO, enters the alveoli at the same hypoxaemic with an inspired oxygen concentration of 21 Yo. However, an interruption to ventilation may prerate itis produced (about 250 mllmin). However, during cipitate catastrophic hypoxaemia so it is important to apnoea most of the CO, produced isbuffered within understandhowsuchincidentsimpairarterialblood the body and only about 2.5% (6 mllmin) enters the gases. First consider theeffect of apnoea while breathing alveoli. Oxygencontinues to be absorbedfromthe alveoli at 300ml/rnin.Inthissituationoxygen is abair. sorbed at 50 times the rate that CO, is evolved and so Resting oxygen consumption is 250-300ml/min in a typical adult. At the onset of apnoea the oxygen availalveolar pressure falls. This causes convective gas flow ableforvitalorganfunction is almost entirely that (not diffusion) through the conducting airways to the stored in the functionalresidual capacity (FRC) (200 ml) alveoli. Provided the patient’s airway remains connected and that combinedwithhaemoglobin (800ml). After to the oxygen supply, oxygen is passively drawn down 2min about half this store is exhausted and the arterial the airway at a rate of about 295ml/min toreplace that consumed. Po, will be less than 4 kPa. In contrast, because CO, is

This chapter will cover aspects of oxygen therapy and the effects of various gas mixtures, airway and ventilatory management, airway fires, ‘bloodless-field’ anaesthesia and postoperative analgesia.

I

There are two situations where apnoeic oxygenation fails. 1 If the patient is disconnected from the oxygen source, forexamplethe face mask is removed to permit laryngoscopy, then room air instead of oxygen is drawn down the trachea at about 295ml/min and in about 30s nitrogenstarts to enterthe alveoli. Since therate of extraction of oxygenfrom an alveolus is determined by its perfusion, air (with its nitrogen) is directed preferentially to the best perfused alveoli. These are located in thedependentparts of thelungwherethe alveoli are not so well inflated and so the oxygenis rapidly diluted in these alveoli andthetime to significant hypoxaemia maybe as little as 2-3 min.This is still substantiallybetter than if thepatienthadnot been preoxygenated. 2 If the airway becomes completely obstructed, then no gascan flow intothe alveoli as oxygenis absorbed. Alveolar volume therefore decreases at 295ml/min. The lowermost alveoli rapidly completely collapse (absorptionatelectasis) and venousblood issuing fromtheir capillaries causes arterial hypoxaemia. By the time onethird of alveolar volume is lost (2-3 min)theshunt fraction will have risen above 50% and hypoxaemia will be severe. These considerations explain why, with careful use of oxygen, it is often possible to allow an extended period of apnoea while a surgical procedure is performed while at other times loss of airway control or ventilation may require urgent intervention to maintain safety. Helium=oxygen versus oxygen therapy in airway obstruction

Heliox (80% helium, 20% oxygen) is about one-third the density of air and would reduce theresistance to gas flow by this amount when gas flow is turbulent. However, even in severe upper airway obstruction the predominant gas-flow regimen is usually laminar. In these cases heliox would increase resistance to gas flow since it is 8% more viscous than air. Air -oxygen mixtures or 100% oxygen aremoreappropriate while definitive therapy to correct the obstruction is established. On the rare occasions when gasflow is predominantly turbulent in the obstructedsegment of the airway,resistance will be inversely proportional to the fifth power of the radius (Fanning’s law) so the range of narrowing associated with serious rather than total obstruction is tiny. Such patients usually cross this range very quickly so do not have timeformuch CO, accumulation to occur. Within this range theuse of heliox may permit a higher minute ventilation and therefore less CO, reten-

tion than wouldbe the case with either airor oxygen but this is notthemainthreat to the patient’s life. The principal risk is that total obstructionwill rapidly supervene and severe hypoxaemia will rapidlyfollow if breathing 20% oxygen (either as helioxor air).In anticipation of this the patient is likely to be safer on high concentrations of oxygen rather than a helium-oxygen mixture while preparationsaremade to relieve the obstuction. Airoxygen versus N,O=oxygen in middle ear surgery

Because N 2 0 is muchmoresoluble than nitrogenit rapidly enters and inflates air-filled cavities. If the cavity is closed and rigid then the pressure rises; hence a partially fluid-filled middle ear may appear dry after induction of anaesthesia with N,O. This may result from the increase in gas volume orthe fluid may actually be expelled from the Eustachiantube along with gasby the high pressure generated by the N,O. Following placement of a tympanic membrane (TM) graft, the middle ear pressure mayrise at about 1-10 cm H,O/min. At the end of anaesthesia absorption of N,O may produce a subatmospheric pressure and retraction of the graft. In the author’sexperience use of N,O does notappear to cause problems,perhaps because the packingtechnique used by his surgeons effectively isolates theexternalsurface of the T M fromatmosphericpressure. In circumstanceswherethesurgeon feels that these pressure changes may be significant the anaesthetist should be informed well in advance. If these effects are to be avoided, N,O should notbe used during the whole procedure and special arrangements may be required to permit the use of an air -oxygen-volatile anaesthetic mixture. Inpatientswithpreviousstapedectomythere have been a few reports of deafness followinganaesthesia (usuallyfornon-otologicalsurgery). Thesehavebeen ascribed to pressure changes leading to dislocation of thestapesprosthesis,either by diffusion of N,O or inflation of the middle ear by positive pressure ventilation by face mask prior to tracheal intubation.

Airway management 1 The airway maybe open and not connected to an anaestheticbreathing system, forexamplewiththe patientbreathingthrough anoperatinglaryngoscope. This is mostoften used to permitsurgerywithinthe larynx or trachea. It may also be appropriate for brief, minor procedures. Reduction of nasal fracture may be

Aspects o f General Anaesthesia forENT Surgery included in this group but this is probably unsafe because of the risk of a brisk nasalhaemorrhage and inhalation of blood. 2 A face mask may be used, with or without a pharyngeal airway (Guedel or nasopharyngeal). 'This approach is suitable for some minor procedures not involving the airway. 3 The laryngeal mask airway is suitable for minor and intermediatesurgery not involving theairway. It can be useful in assisting trachealintubation in selected patients in whom intubation may be difficult by conventional means and for airway maintenance during percutaneousdilatationaltracheostomy. Many anaesthetistsareexperimentingwithits use forroutine pharyngeal, nasaland sinus surgery. It is not certain that itadequatelyprotectsagainstinhalation of blood or other debris, orthat itprovidesa sufficiently secure airway. It will take some years to establish whether the laryngeal mask is as safe as tracheal intubation. 4 Intubation of the tracheaby oral ornasal routes using tubes such as the Magill (standard or armoured),RAE, microlaryngoscopy or flexible metallic LaserFlex tube is the mostwidely used method of airway management for head and neck surgery. While oral intubation isused fortonsillectomy in children (to allow access to the adenoids)it is conventional to use anasaltubefor tonsillectomy in adults. Nasotracheal intubation is significantly more traumatic and the author prefers the oral route for adult tonsillectomy. 5 Tracheostomy or cricothyroidostomy maybe performed and tubes such as plain or fenestrated (speaking) tubesor alaryngectomy (Montando)tube maybe inserted. The severely compromised airway

Whether due to tumour, infection, trauma, a congenital abnormalityor bleeding intothe airway,ventilatory obstruction may requireimmediatetracheostomy or cricothyroidotomy under local anaesthesia. In the most urgent cases even localanaesthesia will be omitted. In less pressing cases it may be appropriate to attempt to secure theairwaywithatrachealtube (awake or undergeneralanaesthesia) ortoattemptto provide general anaesthesia for tracheostomy. In such cases it is essential that the surgical teamis prepared to perform tracheostomy or cricothyroidotomy immediately if control of the airway is lost. When this occurs it must be understoodthat, if theanaesthetisthas not been successful in maintainingoxygenationas described above,theairwaymust besalvaged in amatter of seconds.

3

Ventilatory management Themethod of ventilation usually dependsmore on patient than surgical considerations. 1 Spontaneous ventilation. This is suitable for younger, more robust patients for shorter procedures where moderate hypercapnia will not cause poor operating conditions. 2 Intermittent positive-pressure ventilation (mechanical or manual). Thisis most widely used, particularly where muscle relaxants are used to facilitate placement of the tracheal tube. 3 Low-frequency jet ventilation, e.g. witha Sander's injector. 4 High-frequency jet ventilation alone or superimposed on spontaneous ventilation. Jet ventilation allows positive-pressure ventilation and control of blood gases when an open airway technique is required. Jet ventilation injectors for either high- or low-frequency use may be proximal (mounted on operatinglaryngoscope or rigid bronchoscope)ordistal (e.g. Benjamin andCardentubesandcricothyroid cannulae). These are designed to inject oxygen through an end hole and to entrainair to augmentthetidal volume.

Airway fires Withthediminishing use of flammable anaesthetic agents, airway fires had become rare.However,the introduction of powerful lasers into ENT surgery has caused a re-emergence of this problem. Biological tissues, being waterlogged, do not supportsustained combustion even in anatmosphere of 100% oxygen. Problems arise because the surgeon or anaesthetist introduces extraneous flammable materialssuchas tracheal tubes orcotton swabs,particularly if their flammability is enhanced by high concentrations of N,O or oxygen. To minimise the risks an open airway technique may be used (i.e. notrachealtube).Thepatientmay be allowed to breathe room air spontaneously, although this may be associated with significant hypoxaemia and CO,retention.Furthermore,airwayobstruction (a likely accompaniment to thistype of surgery) will rapidlyprecipitatecatastrophichypoxaemia. Adding oxygen reduces these risks but does not prevent CO, retention. If saline-soaked swabs are placed to protect the distal airway from accidental laser strikes, then the inspired gas may dry them and render them flammable. Even without added oxygen the risk is significant; with oxygen the result can be spectacular.

4

Chapter 1

Anotherproblemwith this technique is that the patient will inhale smoke, blood and aerosolised tumour or virus particles generated by the action of the laser. This may be avoided by jet ventilation using a special jet cannula. The cannula is made of stainless steel and is long enough to be placed through the larynx and distal to the site of surgery. It has side holes and no end hole so does not entrain air. This ensures that gas flow at the operation site is outwards throughout the respiratory cycle and smokeinhalation is thus prevented. The very high gas flows associated with this technique make it imperative that saline-soaked swabsare not used, as they will quickly dry out. Jet ventilation can prevent CO, retention and hypoxaemia,particularly as 100% oxygen is themostcommonly used driving gas. Scavenging of the smoke, tumour and virus particles is required to prevent them being inhaled by the operator. The use of a powerfully oxidising atmospherefor laser surgery is controversial. In this context it should be remembered that N,O is a powerful oxidant and its use mixed with oxygen is no safer than 100% oxygen. Adding even small amounts of oxygen to air greatly increases the risk of a flash fire and 25% oxygen is likely to rapidly accelerate combustion. The risks from hypoxaemia in the anaesthetised patient are less spectacular, although probably much more significant than the risk of fire. It maybe that the most appropriate solution is to avoid introducing potentially flammable material rather than limiting the oxidising potential of the gas mixture. Where surgical access permits, a flexible stainless-steel (LaserFlex) tracheal tube may be used to maintain the airway. The respired gas is kept away from the surgical field so that the above considerations are less relevant. Unfortunately, these tubes are not entirely nonflammable since they are equipped with PVC cuffs to seal the airway. The cuffs are inflated with saline, which serves to .quench a fire in the event of the cuff being struck inadvertently by the laser. This will be less effective with second or subsequent strikes since much of the saline will have drained away after the first. To avoid a fire it is essential to stop surgery and change the tube immediately a cuff is ruptured. Rapidrecognition of cuff rupture is facilitated by adding methylene blue to the saline used for cuff inflation.

4€3100dless-field9anaesthesia f o r ENT surgery Excessive bleeding may make any surgery more difficult and particularly so with operations on the middle ear,

endoscopic sinus surgery and exploration of the neck or base of the skull. It used to be considered that deliberate induction of arterialhypotension was effective and often necessary. However,the need to avoid hypotension when grafting free flaps with microvascular anastomoses and the quality of surgical field that can be obtained during such procedures demonstrates that other factors are more important. These include selection of premedicant drugs, induction technique and timing of tracheal intubation toavoid inducing a tachycardia and increasing cardiac output. Positioning the patient head-up and avoiding extreme positions of the neck will minimise venous bleeding. Locally, vasoconstrictors such as cocaine and adrenaline can be used. Theanaesthetistshould always be informed when these agents are used, not so much because some volatile agents may contraindicate them (such contraindicationsareprobablyoverstated),butmore because ECG and blood-pressure monitors need to be closely observed duringtheir use and haemodynamic and respiratory stability should have been established before they are used. Thisshould apply even to the preanaesthetic use of cocaine where ECG, bloodpressure and pulse oximetermonitoringshould be used.

Perioperatiwe analgesia for ENT surgery and related pharmacological topics Among themore painful ENToperationsarethroat procedures such as tonsillectomy and uvulopalatopharyngoplasty (UPPP). Useof acombination of an opioid such as morphine, a non-steroidal anti-inflammatory analgesic (NSAID) such as diclofenac, paracetamol and infiltration of the tonsillar bed with a local anaesthetic is usually very effective. The use of NSAIDs may be of concern because their effects on platelet function may possibly contribute to post-tonsillectomy haemorrhage. However, inadequate analgesia may also increase the risk of haemorrhage by impairing swallowing and predisposing to infection. Obviously the usual cautions and contraindicationsfor NSAIDs must be observed. Rather less well recognised is that patients with sleep apnoeasyndromescan become very sensitive to the effects of opioids and require less than one-fifth of the normal dose. Some patients requiring tonsillectomy or UPPP belong to this group. Opioids are rarely required for middle ear and labyrinth surgery and can aggravate the postoperative nausea and vomiting associated with this surgery. If they can be avoided then it is often unnecessary to give a

Aspects of GeneralAnaesthesia for ENT Surgery prophylactic antiemetic, although it should be given early if the patient develops nausea. Prochlorperazine is often preferred as an antiemetic, especially after labyrinthectomy, although itis probably not superior to any other antidopaminergic antiemetic. When agents of this class prove ineffective there is a tendency to try newer agents such as ondansetron. This is a pity since hyoscine is probably the most extensively tested antiemetic drug and canbe very effective. If large doses are given (0.8 rng or more in an adult), orin the elderly, there is a small risk of precipitating a confusional state or hallucinations.Wherethis needs treatment, small

5

doses of physostigmine given intravenously are more effective than sedative drugs. Premedication withopioidsand/or anticholinergic drugs is now rarely used. Opioidsare given during anaesthesia according to anticipated need for analgesia postoperatively. Anticholinergic drugs may cause a tachycardia.This may cause myocardial ischaemia in patients with coronary arterydisease or increase cardiac output, thereby compromising a ‘bloodless-field’. They may be givenwhen necessary during surgery when vagal bradycardia is induced by, for example, instrumentation of the ear canal or pressure on the carotid body.

Surgical Outcome Analysis and Audit R O W E N A M. R Y A N

Introduction

come measure, the methods in common use for analysis of outcomes (Table 2.1), the differences between auditand research and finally the role of audit of outcomes.

Research into outcomes of all types of health care, including surgery, currently excites great interest from providers, purchasers, politicians and patients. Surgeons have, of course, always been interested in the outcomes of the procedures they offer, both positive (e.g. myringoplasty take rate) and negative (e.g. morbidity and mortality data). But now alongside a growingmedical interest in the field is a sharp increase in the use by purchasers of outcomes data to inform purchasing decisions. A recent survey by the UK Clearing House for Information on the Assessment of HealthOutcomes (Frater & Dixon, 1994) found that 84% of purchasers were using some sort of information on outcomes for this purpose.Although only 22% of thetotal were influenced by outcomes data in deciding where to place contracts, many used outcomes data in deciding what care to purchase, and expressed a desire for more information about how touse outcomes data to make comparisons between providers. It is essential that those using outcomes data and those generating them should be aware that most outcome studies do not ‘measure’ outcomes in such a way that clear-cut comparisons can be made between treatments or providers. Some studies will do this (randomised controlled trials), but most will not. Consequently results need to be interpreted in the knowledge of the factors whichmay have confounded them; otherwise the scope fordrawinginaccurate conclusions is huge. Now more than ever, individual surgeons need to be aware of the methods in use for outcomes analysis and the virtues and limitations of each. This chapter will discuss thefundamentals of choosing an out-

Choosing an outcome measure Choosing an outcome measure is an essential preliminary to good research and to audit of outcomes. Measures must be chosen with care, precisely defined and validated. For many operations, simply choosing the appropriatetype of outcome measureis difficult. For example, after endoscopic sinus surgery, should symptom relief or endoscopic appearance be used or both? For some operations a simple, objective, easily quantifiable measure will be obviously suitable, such as audiometric data afterstapedectomy.However,formany interventions, themost relevant outcome measure is symptom relief, and some ‘instrument’ such asa questionnaire must be found to quantify that symptom relief. The type of questionnaire in commonest use in surgery is referred to as a ‘measure for specific disease’ (e.g. one relating to symptoms of sinusitis), but many other types have been developed in other specialties, such as measures of pain and ‘multidimensional health status profiles’ (e.g. the recently popular SF-36 questionnaire): Well-documented techniques(McDowell, 1987) exist for quantifying the essential characteristics of a questionnaire designed for use as an outcome measure. These include reliability (whether it produces the same results if reapplied to thesamesituation), validity (whether it measures what it purports to measure) and responsiveness (whether it can identify small but clinically significant changes). 6

Surgical Outcome Analysis and Audit Table 2.1 Methods in common use for outcome analysis.

Methods in CO outcome analysis The randomised controlle

The double-blind randomised controlled trial remains the ‘gold-standard’ methodfor establishing acausal relationship between process and outcome (e.g. does a saccus decompression have a greater effect than placebo on Menikre’s disorder?). In any other type of study, the risk of a goodor a bad outcome may not be totally equal between groups of patients treated with different operations or by different surgeons, and so differences between the outcomes may not mean true differences in process. The only totally unambiguous way of equalising risk between groups (despite ‘case-mix variables’ seeFig. 2.1-and inaccuracy, bias andchance) is through randomised controlled trials. However, these are expensive and time-consuming and indeed unsuitable for many treatments, while some patients will always be too ill or too old or have coexisting disease which requires their exclusion (Greenfield, 1989). This means thatother methods must often be soughtfor practical reasons. Furthermore, before it can be ethically justifiable to mount a randomised controlled trial there

Fig. 2.1 Relationship between case-mix, process and outcome.

7

must be true uncertainty about the issue at question; to establish that such uncertainty exists will often require prior investigation with less formal methods.

These studies do notallow the difference between treatments or providers to be ‘measured’ accurately, but they are used because they are applicable to a wide range of clinical situations rather than just narrow research settings. In these studies patientsare observed and outcomesdocumented,but noattempt is made to randomise, so interpreting the results is extremely difficult as allowances must be made for so many variables. While elaborate ‘risk stratification systems’ have been designed using sets of variables to stratify patients according to risk in particular situations (e.g. the APACHE scoring system (Knaus et al., 1991) for estimating risk of mortality in intensive care), in most circumstances it is impossible to control for all relevant factors. One type of observational study which is so simple that it can be used to trackresults in all surgical patients (rather than just in small subgroups) hasbeen piloted in theRoyalNational Throat Nose and EarHospital (RNTNEH), London.Theapproach involves simply ‘monitoring’ whether or not patients’ operations have achieved their individual goals (Ryan et al., 1994). Before surgery is offered, the patient’s subjective goal (e.g. relief of nasal obstruction) is documented in the notes (Fig. 2.2), as well as an objective goal chosen by the surgeon. Later, at postoperative review, bothpatient and surgeon ask themselves, ‘Has this operation achieved its goal?’ The question may be asked again after a longer interval, by post if necessary. Analysis can

8

Chapter 2 Analysis of mortality rates and 6outcome indicators’

Fig. 2.2 Admissions stamp used at the RNTNEH specifying goals of surgery.

yield some interesting results (e.g. only 40% ‘success’ following antral washouts compared with greater than 70% following endoscopic sinus surgery).However, these results can under no circumstances be used as endpointsin themselves, butonlyaspointers to further study. Complication-rate comparisons

Comparison of rates of specific complicationsafter specific operations may throw a little light on differences between providers, if interpreted with due attention to case mix and other relevant variables. However, many major methodological pitfalls exist. Sample size will be inadequate except with common complications of very common procedures, and the method of data collection will have a profound effect on reporting rates. It has been shown that documenting complications prospectively rather than retrospectively can almost quadruple the numbers reported, while comparisons can be made meaningless by lack of standardisation of issues such as the following: 1 Should the term ‘complication’ include failure of an operation to achieve its end? 2 Should complications of a general anaesthetic be recorded? 3 Should unavoidable consequences of surgery be included, such as facial palsy after total parotidectomy for malignancy? 4 Should all complications be recorded or only the most severe per patient? 5 How severe does each complication have to be to be worth recording (e.g. how much bleeding after a tonsillectomy is ‘significant’?)?

Theterm ‘indicator’ refers to figures calculated from routinely collected data, such as reoperation within 1 year after specific surgical procedures, which might be considered to vary with quality of care. ‘Indicators’ and mortalityratesare widely examined at a national or regional level. While analysis of such data gives informationfor little cost because the dataare collected anyway, suitable ‘indicators’ are few and far between, and results may be confounded not only by case-mix differences, inaccuracy, bias and chance (as with observationalstudies)but also by irrelevant variations in local practice. For example,adeathrate based on finished consultant episodes may appear up to50% less thanone based on in-patient admissions (McKee & Hunter, in press) if moribund patients are referred from oneconsultant to another during an admission, thus completing multiple ‘episodes’ per admission. As finished consultant episodes are at present the denominator in mortality-rate calculations, departments where widespread ‘episode inflation’ occurs will appearto have a significantly lower mortality rate!

Audit Aims and methods

Audit should not be regarded as a tool for defining a causal relationship between process and outcome. This is the province of pure research, which in essenceis ‘concerned with discovering the right thing to do, while audit is concerned with ensuring that it is done right’ (Smith, 1992).Other very important differences between research and audit are outlined in Table 2.2. Rather than lookingfora causative link between process and outcome, audit will investigate process or outcome independently. Where the relationshipbetween Table 2.2 Differences between audit and research.

SurgicalOutcome process and outcome has already been well established (by research), an index of process may even be used as a proxy for outcome. For example, we know that early diagnosis of congenital hearing loss is associated with improved acquisition of speech and language, so it might be reasonable to audit rates of early diagnosis as a proxy outcome measure in these children for the sake of simplicity. Audit methods must be tightly defined and controlled if wastage of funds on poor research, dressed upas audit, is to be avoided. Audit projects are expected to involve the setting of a standard, examinationof current practices against thatstandard, a search for changes which might improve the match with the standard, and re-examination of practice to assess whether or not the changes have brought about an improvement. Audit as practised in this way works well for issues of process (e.g. does every letter to a GP contain a working diagnosis?) andsome issues of outcome (e.g. are we succeeding in discharging 98% of plannedday cases on the same day as surgery?). However, the method is clearly not appropriate forestablishing causative links between process and outcome. An extreme exampleof the sortof methodological sloppiness that can occur if the purpose of audit is misunderstood is for a department to review results following two proceduresdoneforthesame condition, without controls or randomisation, and to conclude on thebasis of the results that oneprocedure is better than theother.Thissort of mistake must be avoided at all costs if audit is not tofall into disreputeby association with valueless pseudoresearch.

Fig. 2.3 Sample comparative audit ranking chart (reproduced with permission o f the Surgical EpidemiologY and Audit Unit at the Royal College of Surgeons of England).

Analysis and Audit

3

Cornparatiwe audit

This has more to do with comparison of processes and outcomes than with audit as defined above. Surgeons pool data fromtheirown practices regarding basic workload (e.g. cases operated on per year, number of theatre lists per week) and special topics (e.g. process and outcome of surgery for sinusitis). The answers from all surgeons for any one question (e.g. percentage take rate after myringoplasty) are then ranked in numerical order,asin Fig. 2.3, so that each surgeon can see whether hidher answer lies around the mean or in a grossly outlying position.Whereindividualsurgeons find they are an outlier with respect to any one question, they may be stimulated to return to their own department and carry out true audit to investigate the cause and bring about an improvement if possible. Comparativeaudit data make little allowance for case-mix factors and none for bias, chance or sample size, so they can only properly be interpreted by the surgeon returning data who knows how these factors might have affected hidher results. For this reason data and rankings are kept strictly confidential.

The future There is no doubt thatthe ‘outcomes industry’ is here to stay. This will be welcomed by doctors provided the emphasis is genuinely on improvingoutcomesrather thanwitch-hunting‘bad apples’, and provided those using outcomes data show a sufficient grasp of the prin-

IO

Chapter 2

ciples outlined above for them to be able to interpret outcomes data sensibly. In particular, the point cannot be emphasised too firmly that outcome indicators and observational studies of outcome do not provide sharp enoughinformation to clearly define therelationship between process and outcome, and therefore should be used very cautiously, if at all, to makecomparisons between providers. The future of outcomes research should include more attention to defining and validating outcome measures, a greater drive towards getting results of good research into day-to-day practice, and a more widespread effort to analyse outcomes in a cooperative, constructive and non-confrontational way. Doctors are far morelikely to be able to influence the direction of outcomes initiatives from a position of experience within the field, and this should addto the satisfaction derived by individual surgeons from the intelligent informed use of their own outcomes data.

References Frater A & Dixon P (1994)Purchasers’ survey. Outcomes Briefing 3, 2.5-6. Greenfield S (1989) The stateof outcome research: are we on target? N.Engl. J.Med. 320, 2142-3. Knaus WA, Wagner DP, Draper EA etal. (1991) APACHE 111 prognostic system: risk prediction of hospital mortality for critically ill hospitalized patients. Chest 100, 1619-36. McDovvell I (1987) A Guideto Rating Scales andQuestionnaires. Oxford, Oxford University Press. do they McKee M & Hunter D (in press) Mortality league tables: inform or mislead? Quai. Health Care (in press). Ryan R, White C & East C (1994) Global monitoring of positive outcomeaftersurgery:afeasibilitystudy at the Royal National Throat Nose and Ear Hospital. Ann. Roy. Coll. Surg. Engl. 76,759. Smith R (1992) Audit and research. BT. Med. J.305, 90.5-6.

Otology Middle Ea

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Excision of Lesions of the Pinna M I C H A E L C.F. T O N G A N D ASHRAFZEKRI

lndications Surgical excision of partor whole of thepinna is indicated for both benign and malignant pathologies. Benign lesions of the pinna include hypertrophic scar, keloid, seborrhoeickeratosis,solarkeratosis,pilomatricoma, solar lentigo (lentigo seniles), benign melanocytic naevus, pyoderma gangrenosurn, papilloma, lipoma, lymphangioma, leiomyoma, chondroma, haemangioma and keratoacanthoma. Malignant lesions include squamous-cell carcinoma (SCC), verrucous carcinoma (rare), basal-cell carcinoma, malignant melanoma, Kaposi sarcoma and metastatic tumours. A small benign-looking lesion isremoved with primary closure for histological examination to look for possible malignancy. Centrallylocated moderate-size lesions (around 1cm in diameter) can be taken with the defect covered by a split or full-thickness skin graft. For cosmetic reasonsreconstructionwitha randomor vascularised flap isnecessary for large benign lesions and most malignant lesions. Alternatives to surgical removal, including shave excision, lasering, electrodesiccation and cryosurgery, will be briefly outlined.

Preoperative management Clinical diagnosis of most lesions of the pinna can be accurately madeby careful examination noting the characteristics of its growth, colour, shape, edges and consistency. Preoperative diagnostic biopsy is indicated for largedoubtful lesions to allowforbetteroperative planning. In patients withsuspected SCC or melanoma, theregionallymphatics-preauricular,postauricular andupper cervical nodes- have to be palpatedfor metastases. It is advisable to discuss andthoroughly

explain to patients the various options for reconstruction and the cosmetic outcome of the planned operative procedures.

Relevant anatomy Understanding of the basic cartilaginous framework of thepinna is an essential prerequisite (Fig. 3.1). If a majorreconstruction is planned,moulding or photographic imaging of the contralateral normal earmay be helpful during the operation.

Operative techniques Most lesions can be removed under local anaesthesiaby subcutaneous infiltration of 0.5 -1 % lignocaine without adrenaline (to avoid the possibility of ischaemic necrosis). As premedication, 5-10 mg of diazepam (Valium) can be given. Formalignant or infected lesions with perichondritis, general anaesthesia is recommended. Planned incisions aremarked precisely before infiltrationandthedrapedareashould allowadequate exposure of the ear and the potential areas for reconstruction.

Procedures The patient is positioned comfortably slightly head-up and the ear canalprotected by cotton wool or asilicone ear plug. The technique of closure and reconstruction depends on the size and site of the lesion. 1 For small benign lesions (less than 5 mm in diameter) whena 1-:!mm margin is adequate, simple elliptical excision and primary closure with 5/0 non-absorbable sutures (Ethilon, Dermalon) will suffice (Fig. 3.2a).

14

Chapter 3

2 For centrally located moderate-size lesions (5-10mm in diameter), with preservation of the perichondrium, split or full-thickness skin graft can be applied with a bolster dressing (Fig. 3.2b). 3 For peripherally located small-size lesions, anadvancement helical flap can be applied (Fig. 3 . 2 ~ ) .

Fig. 3.1 Anatomy of the anterior surface of the right pinna: 1, helix; 2, triangular fossa; 3, scapha; 4, antihelix; 5, concha; 6, tragus; 7, antitragus; 8, lobule.

Chondrocutaneous flaps (Antia & Buch, 1967’) can be used for larger helical-rim defects (Fig. 3.3). This’technique necessitates total freeing of the entire helix from thescapha by incising throughthe cartilage. The posteromedial skin is dissected away from the perichondrium, mobilising the two ends of the helical remnants to close without tension. 4 Large benign lesions or malignant lesions require a safety margin. Closure of the resulting defect depends on its location at the upper, middle or lower third of the conchal area. Aresection margin of 2-3 mm is adequate for basal-cell carcinoma, whereas at least 5 mm clear full-thickness ‘skin-cartilage-skin’ margin is necessary for squamous-cell carcinoma. 5 Upper-third lesions are excised using a wedge incision (Orton, 1986; Furnas, 1990). The closure is either primary anteriorly with a skin graft or posteriorly with a postauricular flap (Fig. 3.4a). A free composite skincartilage graft may be used from the opposite ear (Fig. 3.4b). 6 Middle-third and conchal defects can be closed by a postauricular flap with or withouta cartilage graft(Fig. 3.5). A stent or an acrylic mould must be placed in the external auditory canal (EAC) opening for 4 months to prevent subsequent stenosis (Brent, 1990). 7 Tumours of the lower third or earlobe can be excised using primary closure. Soft-tissue reconstruction alone is adequate.Themethod of Converse (Converse & McCarthy, 1977; Brent, 1990) for ear-lobe reconstruction can be applied (Fig. 3.6).

Fig. 3.2 Method for excision and closure of small benign lesions. (a) Simple elliptical closure; (b) circumferential excision with skin graft; (c) advancement helical flap.

Excision of Lesions

Fig. 3.3 Chondrocutaneous Antia and Buch flap for large helical-rim defects.

Fig. 3.4 Closure of large upper-third lesion of the pinna. (a) Postauricular flap. (b)Free composite skin-cartilage graft.

of

the Pinna

I5

i-

\

Fig. 3.6 Converse’s method of ear-lobule

reconstruction.

Fig. 3.7 Examples of geometric wedge and crescent excisions of the pinna.

8 Geometric wedge and crescent excisions. There are numerous ways of partially excising theearwitha predesigned geometric pattern of excisions. Examples are given in Fig. 3.7(Converse & McCarthy, 1977; Brent, 1990; Furnas, 1990). If the basic rules of plastic reconstructionareapplied,thepostoperativeappearance using any of these designs will be similar. 9 Reconstruction of a total or subtotal auricular defect utilises the same principles as for the management of congenital atretic or microtic ears. The soft-tissue defect must be well covered during the initial surgery to allow for subsequent reconstruction. Options include plastic reconstruction or an auricular prosthesis secured on an osseo-integrated framework.

Compressive gauze bolster dressings are kept in place for 7-10 days postoperatively with stitches removed at

the same time. Oral antibiotics (ampicillin and cloxacillin) aremaintainedfora period- of 1 week postoperatively. A protective dressing is to be worn during sleep to avoid ischaemic necrosis.

i~ati Early postoperative complications can involve the wound or the donor area. Faults in surgical planning result in inaccurate positioning of the reconstructed ear (Furnas,1992). Apoorly designed framework is reflected in an obviously deformed ear. Skin necrosis from random flaps, haematomas and seromas predispose to secondary infection. Bleeding and haematomaformation usually result fromrebound effects of topical adrenaline, which should be avoided. Cautious haemostasis by the use of fine-tip bipolar electrocautery is recommended. Allergic responses to dressing or conformer materials sometimes hamper graft success.

Excision of Lesions of thePinna

Rarely a pneumothorax with atelectasis might occur as a complication of obtaining rib graft for reconstruction. Late complications include failure of reconstruction as the cartilaginous framework is absorbed and organised. Secondaryreconstructionmight benecessary to improve the cosmetic outcome. Hypertrophic scars and keloids at the primary surgical site or postauricular scars rnay be a sequel to the operative trauma. Triamcinolone injection into the scarred area rnay prevent further deterioration of hypertrophic scars. Psychological considerations should not be neglected and preoperative counselling should be thorough.

s

Laser scalpel

The carbon dioxide laser offers little advantage when excising mostcutaneous lesions. For benign warty growths where the histology is not in doubt, laser vaporisation can be an alternative to simple excision. Haemangiomatous lesions

Tunable dye laser (577 or585 nm), copper vapour laser (578 nm) or argon laser (540nm) is effective in the treatment of these lesions and provides an excellent cosmetic result as an alternative to extensive local excision.

ee

17

esie

Low-power monopolar diathermy can be employed to ablate benign superficial lesions. Shave excision or cryosurgery serves the same purpose.

Intralesional excision with preservation of the epithelial lining followed by postoperative splinting and steroid injections offers a good result in the treatment of these lesions (Converse & McCarthy, 197’7).

Antia NH & BuchVI(1967) Chondrocutaneousadvancement of flap forthemarginaldefect of theear. Plast. Reconstr. Surg. 39, 472. Brent B (1990) Reconstruction of the auricle. In: McCarthy J G (ed.) PlasticSurgery, Vol. 3. Philadelphia,W.B.Saunders, pp. 2094152. Converse J M & McCarthy JG (eds) (1977) Reconstructive Plastic Surgery, Vol. 3. Philadelphia, W.B. Saunders. Furnas DW (1990) External ear. In: Jurkiewicz MJ, Krizek TJ, Mathes SJ & Ariyan S (eds) Plastic Surgery: Principle and Practice. St Louis, C.V. Mosby, pp. 171-206. Furnas DW (1992) Otoplasty. In: Peck GC (ed.) Complications and Problems in Aesthetic Plastic Surgery. New York, Gower Medical Publishing, pp. 8.1-8.13. Orton C (1986) Lesions of the pinna. In: BallantyneJ C & Morrison A Surgery-Ear. London, (eds) Rob C.+ Smith’s Operative Butterworths, pp. 1-10.

It is not necessary to excise all preauricular sinuses. Many may be kept quiescent by regular expression of retainedsebaceousmaterial. Some, however, become infected and causerecurrentpain, swelling, offensive discharge and even abscess formation when the sinus becomes blocked. Preauricular sinuses which manifest symptoms of infection should be excised. Repeated infections causing fibrosis around the sinus make complete excision more difficult, and increase the chancesof leaving behind squamous epithelium resulting in recurrence. Incomplete surgery causes similar problems.

Preauricular sinus is usually situated with its opening in front of the ascending limb of the helix. From here it extends into the subcutaneous tissue but usually remains superficial to the plane of the parotid fascia, which is an upward extension of the investing layer of deep cervical fascia. The parotid fascia also lies in the same plane as the superficial temporalis fascia, the twobeing separated by the root of the zygoma. The parotid fascia therefore serves as a useful landmark in this operation so that, whenever there is difficulty in identifying the sinus, excision of all the soft tissue between this fascia and the overlying skin helps ensure removal of all the buried squamous epithelium. As long as the surgeon stays superficial to this fascia, damage to the facial nerve is avoided. With experience, thewhitishcolour of this fascia is quite easy to recognise, However, if difficulties arise, the temporalis fascia should be identified initially andthen followed inferiorly to reachtheparotid fascia.

A history of previous infection should be confirmed. It is notuncommon to have bilateralpreauricular sinuses and thisshould be noted even if asymptomatic. If a contralateral sinus is present, bilateral excision is only offered if the above-mentioned indications exist. Complete examination of theear, including tuning-fork tests, should be performed to exclude other congenital malformations. If the patient is first seen during an acute infection of the sinus, antibiotic therapy shouldbe given and elective excision delayed until the infection has subsided. Sometimes, the patient presents with a preauricular abscess. Initial treatment would then consist of drainage via a small stab incision, Eusol dressing and antibiotic therapy. At this stage attempts at complete excision of the sinus are associated with a high rate of recurrence as the friable sinus wall is liable to tear at multiple sites, leaving residual squamous epithelium behind.

r

.

1 Anaesthesia. General anaesthesia with endotracheal intubation is requiredfor all children andanxious adults. Local infiltration anaesthesia withlignocaine 2 % with 1 in 80000 adrenalinecan beused forroutine 0.1 mg/kg adultoperations.Sedationwithmorphine body weight isgiven intramuscularly 30min before commencement of operation. Even in patients operated under general anaesthesia, infiltration with 2ml of the lignocaine-adrenaline solution isuseful to promote 18

Excision of Preauricular Sinus

19

Fig. 4.1 An elliptical incision around the opening of the sinus.

Fig. 4.2 Dissection of the anterior skin flap.

vasoconstriction and ensure arelatively bloodless operative field. 2 No prophylactic antibiotic is required when operating on a non-infected sinus. 3 The patient is placed in a supine position with head turned away from the side of operation. 4 A small amount of methylene blue is injected gently into the sinus with a blunt needle at the start of the procedure. The blue discoloration of the sinus tract will warnthe surgeon if this is breached. Injection with excessive pressure may rupture the sinus and the resultant leakage of dye will discolour theoperative field, making the procedure more difficult.

skin, leaving the subcutaneous tissue containing the sinus tract undisturbed. 2 Withan assistant providing goodretraction using skin hooks, the exposed subcutaneoustissue is dissected off the underlying parotid fascia. If there is difficulty in identification, the incision can be extended for a further centimetre superiorly to identify the temporalis fascia, which is then traced inferiorly to the parotid fascia. One should always be on the lookout for the bluish coloration of the methylene blue in the sinus. 3 The elliptical island of skin around the openingof the sinus together with the dissected subcutaneous tissue is then held with Allis tissue forceps (Fig. 4.3). Dissection is continued posteriorly until theperichondrium of the helical cartilage is reached. It is not uncommon for the fundus of the sinus to be densely adherent to the perichondrium and a segment of the latter should be excised together with the whole specimen. 4 Meticulous haemostasis must be maintained throughout the whole procedure by electrocoagulation of all bleeding points so as to provide optimum visualisation of residual squamous epithelium and the blue coloration of the sinus tract.

Incision

An elliptical incision is made around the openingof the sinus, as shown in Fig. 4.1. This incision can be extended superiorly and inferiorly as indicated, depending on the individual situation. Procedure in stages 3. Using a scalpel with a no. 15 blade, the anterior skin flap is dissected for about 2cm (Fig. 4.2). The posterior flap is elevated to the perichondrium of the helical cartilage. Care should be taken to limit the elevation to the

Closure/drainage/dressing

The wound is closed with interrupted 4/0

prolene su-

Fig. 4.3 Skin retracted and tissue held with Allis tissue forceps.

Fig. 4.4 Closure with prolene sutures.

tures (Fig. 4.4). If there is a risk of oozing at the end of the procedure, a twisted nylon drain is placed at the inferior end of the wound. A pressure bandage is then applied.

Allternatiu

ostoperative management The dressing and drain (if used) are removed after 24 h. A fresh gauze dressing is applied. Stitches are removed after 1 week.

ompllications l Haematoma -when haemostasis is inadequate and drainlpressure bandage not used. 2 Abscess-when the haematoma becomes infected. 3 Recurrence -when excision of the squamous epithelium of the sinus tract is incomplete; these cells collect underthe skin and breakthrough, resulting in sinus formation.

A supra-auricular approach has been described (Prasad et al., 1990) in which the sinus is approached via a supra-auricular incision, the temporalis fascia routinely identified and all tissue superficial to this removed. The use of the operating microscope has also been used to enhance the identification and dissection of the sinus tract (Raman, 1990).

Prasad S, Grundfast K & Milrnoe G (1990) Management of congenital preauricularpitand sinus tract in children. Laryngoscope 100, 320-1. Rarnan R (1990) Excision of preauricular sinus. Arch. Otoluryngol. Heud Neck Surg. 116, 1452.

a te stose

s

KEVIN J. FEELY

Relevant anatomy Indications for surgery for both osteomas andexostoses of the external auditory canal (EAC) relate to the following: 1 canal obstructive symptoms: (a) recurrent wax impaction; (b) water entrapment; (c) conductive hearing loss; 2 recurrent otitis externa; 3 access for unrelated surgery, e.g. stapedectomy. While exostoses arecommon,the need for surgical treatment is uncommon. Relative contraindications include the following: 1 asymptomatic lesions; 2 advanced age or general debility; 3 involvement of an only hearing ear.

Exostoses and osteomas are distinct and separate conditions involving the tympanic plate(Fig. 5.1).This is a Cshaped bony plate larger and thicker anteriorlyand inferiorly. The plate is open superiorly at the notch of Rivinus. Bony osteomasarerare and typically solitary and unilateral. They are of variable size, presenting at any age in either sex and pedicled in the lateral canal at the tympanosquamous or tympanomastoid suture. Smaller lesions are not uncommon and may arise in the deep canal,oftenadjacent to thetympanicannulus. These smaller lesions rarely cause problems. Bony exostoses, on theotherhand,arecommon, typically bilateral, symmetric, sessile thickenings of the tympanic plate, occurring predominantlyin adult males. Size of individual lesions varies, but usually the anterior exostosis is the larger one.The sessile thickening extends from the tympanic annuluslaterally to involve the whole width of the plate. Theextent of surgery is limited by thetemporomandibularjoint (TMJ) anteriorly,the facial nerve posteriorly and the eardrum medially. Complications of surgery relate to these structures and in particular the variable relationship of the facial nerve to the posterior tympanic annulus is of great importance. In at least onethird of cases, the facial nerve will come to lie lateral to the plane of the tympanic annulus in its vertical descent to the stylomastoid foramen. The nerve lies closest to the posterior wall of the deep bony canal adjacent to the posteroinferior quadrant andmay be separated from the external canal by only 2-4 mm in this region (Litton et al., 1969; Williams, 1988). It is for this reason that the surgical approach should be designed to give optimum

In the case of exosfoses where staged bilateral surgery may be necessary, it is simply a case of deciding which is themostproblematicearfor initial surgery. Regular preoperative suction ear toilet and possible topical antimicrobial agents may be required to resolve any associated otitis externa. The ears should be kept dry. For osteomas it may be possible on initial examination to determine the locationand thickness of the bony pedicle. This may influence choice of permeatal or endaural approach as well as the use of local or general anaesthesia. Specific preoperative investigations are limited to a baseline audiogram. Radiological assessment and bacterial culture are unnecessary as a routine. 21

22

Chapter 5 ably occurs (Fagan, 1990). Good exposure is essential for the preservation of the delicate external canal skin over the exostosis. Procedure

Fig. 5.1 Normal tympanic plate. Note thickness o f tympanic plate anteriorly and interiorly.

access posteriorly, and drilling should never extend posterior to the vertical plane of the posterior annulus.

Operative tec Preparation

1 General anaesthetic (GA) (local anaesthetic (LA) may be adequate for a small osteoma). 2 Antibiotics are not routinely used. 3 Thepatient is positioned supine onthe operating table, with 20" of head-up tilt. The head is turned away from the surgeon, with the operated ear uppermost. 4 Infiltration withmarcaine 0.5% withadrenaline 1:200000 aroundtheexternalmeatusandpostauricular region is performed after anaesthetic induction and prior to scrubbing and draping.

1 Thepostauricular incision extends well forward superiorly to allow exposure of the root of the zygoma. The incision continues down to 6 o'clock and is taken A deep to theperiosteumwithcuttingdiathermy. subperiosteal flap is raised anteriorly with a Freer's or Howarth elevator to expose the lateral bony meatus. A self-retaining retractor is placed and haemostasis achieved. 2 The lateral external canal skinis mobilised circumferentially from the bony canal with a Freer's and Rosen elevator to create a sleeve of skin. This sleeve is developed medially as far as theexostoses permit. The externalcanalskin sleeveis transected completely asfar medially as possible and reflected anterolaterally with the pinna under the self-retaining retractor. This step allows good exposure of the entire circumference of the bony meatus, allows access to the lateral aspect of the exostoses and protects the lateral canal skin from-accidental injury from the high-speed drill working in the deep canal (see Fig. 5.2). 3 The anterior exostosis is approached first as it is the largest and furthest removed from the facial nerve. Removal of the exostosis allows easy access to and improved exposure of the posterior lesion where drilling puts the facial nerve theoretically at risk.

Incision

Osteomas

These can often be removed permeatally by snapping the fine pedicle with light pressure applied tothe osteoma with aFreer's knife. For a thicker pedicle which does not snap easily, a fine-gauge or small cutting burr may be necessary to cut across the pedicle. In the rare case of a large osteoma medial to the canal isthmus, it may be necessary to enlarge theisthmuswitha drill from a postauricular approach (Sheehy, 1981-82). Exostoses

The author always uses a postauricular approach. This allows wide access to the whole of the external canal, especially anteriorly where the larger exostosis invari-

__.

Fig. 5.2 Postauricular approach to right ear.

Excision of Canal Osteomas and Exostoses

23

Fig. 5.3 (a) Maximum length of lateral canal skin sleeve is reflected out of canal. (b)Anterior exostosis is ‘cored’ out.

Theanterior exostosis is ‘cored’ out using a highspeed drill and medium cuttingburr. No attempt is made to elevate thethin overlying canal skin, which is protected by maintaining a thin bony cortex as the exostosis is hollowed out. Working from within the exostosis a gutter is created superiorly and inferiorly in the thickest areas of thetympanic plate, withthe drillworking between these guttersbackwards and forwards over the prominence of the TMJ, all the time looking for the bluish sheen of the TMJ through the hard white exostotic bone to avoid entering the joint. As one proceeds medially the white line of the anterior annulus indicates the medial depth of drilling. Once these twolandmarksare identified, the exostosis is continuallythinnedsuperiorly and inferiorly until an egg shell veneer is all that is left. This cortex is then snapped off and either removed or reflected medially withthe still attached overlying skin to form an additional protective layer for the eardrum (Fig. 5.3a). Should there still be a thin lip of bone obscuring the anterior drum, this may safely be taken down with afine sharp bone curette or small diamond burr. The author prefers a curettebecause in this area the eardrumis most at risk of perforation from asmall burr if it skids off the bony lip. 4 Some authors suggest approachingthe smaller remaining posterior (and possibly thethirdsuperior) exostosis ina similar coring-outfashion.The author finds that, once the large anterior exostosis is removed completely, there is sufficient exposure to elevate the posterior canal skin medially and forward to add another protective layer to the eardrum (Fig. 5.3b). The remaining posterior exostotic prominenceis then simply drilled down to a vertical plane in the line of the posterior annulus. This plane marks the posterior extent of

drilling so as to protectanylateral underlying facial nerve. The entire circumference of the drum should now be easily seen. 5 Theanteriorandposterior deep meatalskin flaps overlying the drum are now lifted up and incised along their length witha sickle knife or microscissors to allowredraping over the widened deep bony canal. Semicrushed gelatin sponge strips are used to pack the skin of the deep canal down on to its new bed. The lateral skin sleeve is freed from the self-retaining retractor and likewise incked longitudinally and laid over the lateral bony meatus. This is held in place with one or two Pope sponge otowicksintroducedintothecanal permeatally. Water-soluble antibioticlsteroid drops are used regularly to moisten and expand the wicks. Closure/drainage/dressings

The postauricular incision is closed in layers with 3/0 chromic gut and nylon sutures. No drains are used but a pressure dressing is applied for 48 h.

Postoperative management The patient is reviewed at 7 days when the sutures and canal dressing are removed, and the canal filled with an antibiotic ointment. Completehealing of the canal takes 4-6 weeks.

Compiications 1 Inadequate removal. 2 Perforation of tympanic membrane (TM). 3 Canal stenosis.

24

Chapter S

4 Facial palsy. 5 Deafness: (a) conductive from ossicular or drum injury; (b) sensorineural injury fromtransmission of drill vibration through the ossicular chain.

Acknowledgements The author’s technique as described was developed from the work and teachings of Dr Paul Fagan and Dr Barry Scrivener. The authorwishes to acknowledge their great contribution to his otological education and to express his sincere gratitude.

References Fagan PA (1990)The surgical removal of aural exostoses. J. Otoluryngol. Soc. Aust. 6, 220-1. Litton W, Krause C, Anson B & Cohen W (1969) Relationship of facial canal to the annular sulcus. Laryngoscope 79, 1584-604. Sheehy JL (1981-82) Exostoses and osteomata of the external auditory canal: a report of 100 patients. J.Otolaryngol Soc. Aust. 5,437. Williams B (1988) TEe relationship of the facial nerve to the tympanic annulus of the external auditory canal.J.Otolaryngol. Soc. Aust. 6, 95-6.

ROBERT E. QUINEY

llndications 1 Meatoplasty is most frequently performed at the time of modified radical or radical mastoidectomy. One of the major reasons for the failure of a mastoid cavity to become a dry skin-lined bowl is poor meatoplasty technique. A narrow entrance to the mastoid cavity gives poor ventilation to the skin of the mastoid bowl and poor access for suction clearance of accumulated debris. Poor ventilation of a skin-lined cavity leaves the outer skin layers moist, which leads to increased surface-layer desquamation. This, in a moist environment, quickly becomes infected. 2 Collapsed ear canals. This can occur with ageing. The pinnacontinues to slowly enlarge throughoutadulthoodand,astheconchal well expands, this hasthe effect of collapsing the cartilaginous (lateral) partof the ear canal to a vertical slit. A collapsed cartilaginous canal can also occur some years after a postaural incision for previous mastoid or myringoplasty surgery. Whenthe periosteum of the mastoid that is adherent to the posterior ear-canal skin has not been sutured back, the posterior canal wall may migrate forwards. 3 Acquired meatal stenosis: (a) following chronic inflammation, e.g. chronic otitis externa; (b) idiopathic; (c) postsurgical meatal stenosis; (d) exostoses or isolated osteoma of the ear canal. 4 Congenital meatal stenosis of varying severity. This may be unilateral or bilateral, or associated with developmental abnormalities of the pinna and the middle and inner ear.

Differing surgical techniques are required for all these various types of stenosis. The surgical methods used can be usefully divided into two groups, dependiag on the presence or absence of normal deep meatal skin that has the ability for lateral migration: 1 In meatoplastyformastoid surgery, collapsing ear canals and some forms of acquired meatal stenosis, e.g. exostoses, chronicotitisexterna and minimal deep meatal stenosis, there is some normalmeatalskin present. If this is preserved, then migrating epithelialisation will occur after meatoplasty to cover the exposed soft tissues and bone. 2 In severe deep meatal stenosis where there is no normal deep meatal skin or in congenital meatal stenosis (where meatalskin has never formed), new skin must be brought into the ear canal, preferably by means of skin flaps rather than asplit skin graft, forepithelialisation to have any chance of success.

Preoperative mana No specific preoperativemanagement is required for simple meatoplasty at the time of mastoid surgery. A lateral oblique mastoid X-ray showing the size of the mastoid air-cell system helps in planning for a large or small meatoplastyandthe type of skin incisions, endaural or postaural. In acquired deep meatal stenosis a coronal CT scan will help define the presence of a middle ear cleft, the presence or absence of a normal eardrum, the depth of stenosis and its relationship to the tympanic membrane (TM) *

26

Chapter 6

Relevant anat The lateral third of the external auditory canal(EAC) is formed by a cylinder of cartilage in continuity with the cartilage of the concha. Thiscartilage is covered by thick hair-bearing skin. The inner two-thirds of the EAC is formed by the bone of the tympanic ring, into which fits the cartilage of the outer third as two cups, fitting one into the other. Inthis transitional region the skin of the earcanal is non-hair-bearing, much thinner and has migratory properties. In the deepest third of theear canal migrating skin is directly adherent to the underlying bone and the skin is at its thinnest. Successful meatoplasty needs to addressboththe bony and the cartilaginous part of the ear canal,and the technique to achieve success in these two regions is different.

Operative tec~nique Meatoplasty at the time of mastoid surgery

Preparation

Normally general anaesthesia with patient supine, head rotated and supported on a head ring. Infiltration with a vasoconstrictor, such as adrenaline, at the begining of the operation will have lost its effect whenthe time comes to perform the meatoplasty.After finishing all the bone work, infiltrate the whole of theconchal well between skin and cartilage with 1 in 80000 or 1 in

Fig. 6.1 (a) Relationships of mastoid bowl to pinna. Lateral projection. (b) Conchal well cartilage. Excision margins for single flap meatoplasty. (c) Inferior-based single-flap meatoplasty. (d) Posterior-based single-flap rneatoplasty.

200000 adrenaline. This not only provides some haemostasis for what is often a ratherhaemorrhagic procedure but also helps separate the tissue planes for ease of dissection. Once the mastoid bowl is lined and mostly packed with dressing, then the meatoplasty can be performed without disturbing the mastoid or middle ear tissues. Incision

With either a postaural or endaural incision, allow the pinna to fall back to its naturalposition and use a marking pen to plan the correctsize of meatoplasty. The annulus at the tympanic membraneis often superiorand posterior to the position of the meatus entrance when the ear is inspected from the side, and the surface landmark of the mastoid bowl, attic and antrum is often over the root of the helix or even over the antihelix of the pinna (see Fig. 6.1a). It is cosmetically disfiguring and unacceptable to remove a large amount of the root of the helix so an adequate meatoylasty must be marked out in the well of the ear with only minimal disruption to the root of the helix. Use one or twoneedles entering theskin of the well of the ear, passing through the pinna posteriorly, to mark out from behind how much soft tissue and cartilage needs to be excised via thepostaural incision (Fig. 6.1b). The cartilage is thickest furthest away from the meatus and is most easily identified here by cutting with a knife through the softtissues to the cartilage with one finger held in the concha. Once the cartilage is incised,

Meatoplasty the free edge of the cartilage canbe held with skin hooks while small sharp-pointed scissors dissect the skiQ crf the conchal well andposteriorcanal wall of themeatus away from the cartilage and the underlying soft tissues. There is always a temptation to remove too little cartilage but often a good half of the conchal cartilage must be removed to provide a good-sized rneatoplasty, which with time will inevitably become smaller. It is easiest to remove the cartilage as a single piece before cutting the skin flaps. Theauthor prefers to use a single skin flap based either inferiorly (see Fig. 6.lc), which drapes over the facial ridge, or posteriorly, which runs into the posterior aspect of the mastoid bowl (see Fig. 6. Id). The threeflap and five-flap Portman meatoplasty is well described and a variation with four or five flaps extending far out into the conchal well is shown in Figs 6.2 and 6.3. With a single-flap technique there is often quite a lot of exposed cartilage at the edge of the rneatoplasty and thisshould be trimmed back 1-2mm, preserving the overlying skin, which can then drape over the exposed cartilage edge. This is best done using skin hooks and small sharp-pointed scissors to remove the cartilage piecerncal. The removal of proud cartilage is particularly important if theroot of the helix has been exposed. Sometimes the root of the helix will run right across the concha to end almost at the antitragus, and this inevitably means part of this cartilage is cut through.Thiscartilage is always thick andanextra

Fig. 6.3 (a) Skin incision for five-flap meatoplasty. (b)Classic three-flap meatoplasty skin incision.

27

millimetre or so must be removed to allow the skin to drape over and cover the bare area of cartilage. If the skin does not fold over this area neatly, a single suture can be used to approximate the skin edge and

Fig. 6.2 Skin flaps for four-flap meatoplasty.

28

Chapter 6

thereby close off the exposed cartilage of the helix root. With an endaural incision which has been made between the tragus and the root of the helix, a posteriorly or inferiorly based conchomeatal flap can be dissected out in a similar fashion. However, the cartilage in this surgical approach is often more easily identified along the superior incision of the meatoplasty flap, which is inevitably in continuitywiththeendaural incision. Again, fine sharp-pointed scissors are used to carefully separate thecartilage and underlying soft tissue from the meatal and conchal well skin that will be used to fashion the meatoplasty flap. In planningmeatoplasty incisions inthe skin, it is important to remember the simple rule of random-pattern flap design, where, to avoid significant necrosis of the flap tip, the base: length ratio should be approximately 1:1. With a single flap that is posteriorly based it is very easy to exceed this ratio if the base of the flap is made too narrow by trying to avoid the root of the helix (for this reason an inferiorly based flap is often preferable to one based posteriorly). The deep meatal skin is the migrating epithelium and this must be preserved on a flap with an adequate base if it is to survive and proliferate. In the case of a three-, four- or five-flap meatoplasty,base: length ratio isless important,but again meticulous care must be taken to preserve skin from thedeep meatus, which is then used to fold into the mastoid bowl and promote epithelialisation. Closure, drainage, dressings

Once the meatoplasty has been made and haemostasis secured, the pinna is placed back in its normal position. Packing of themastoid bowl continuesthroughthe meatus itself ensuring that the skin flaps lie on top of any mastoid bowl lining, such as temporalis fascia. The packing of themeatusmust be firm enough to hold the flaps in position and also at its most lateral to hold the meatus wide open at the entrance. Tagging sutures of 410 catgut can be used to hold skin flaps in position but are not used routinely. They should not be used to hold open a meatal flap that fails to stay in position because inadequate cartilage and soft tissue have been removed. With an endaural incision the skin of the endaural incision can be loosely closed and there is no need to continue this closure into the meatus. Leaving the endaural incision open at its most inferior point and then packing themeatuswith dressing also helps to produce a larger meatoplasty. When a postaural incision has been used and a large meatoplasty created, the posterior edge of the meatoplasty will often come close to thepostaural

sulcus. In such cases (where it is knownthere is the possibility of a large mastoid cavity), thenan initial skin incision 1cm behind the postaural sulcus makes closing the wound easier. Periosteum over the mastoid canbe sutured to the soft tissue of the pinna behind the edge of the meatoplasty. This will not only hold the meatoplasty open but provides a sound two-layer closure, reducing the chance of a postoperative postaural fistula occurring. The author prefers to leave a bismuth, iodoform and paraffin paste (BIPP) pack in place for 4-6 weeks witha large meatoplasty technique. Not only does this allowthe meatoplastyentrance to stabilise butitalso allows epithelialisation of a large mastoid bowl to proceed without disturbance. Complications

If cartiiage is exposed, postoperative perichondritis is possible, particularly if therewas an active mastoid infection or if inadequatehaemostatishas been obtained. Prophylactic postoperative antibiotics should be used in such cases. Granulation tissue at the free edge of the meatoplasty incision is more likely if exposed cartilage has not been well trimmed back. Persistent granulations at the entrance to the meatus can be either removed or cauterised with silver nitrate. If exposed cartilage persists, this should be trimmed back asa minor procedure underlocal anaesthetic (LA).Persistent granulations also result in increased cicatricial scarring, which with time will reduce the size of the meatoplasty entrance. Meatoplasty for collapsed ear canals

Indications

Occasionally a collapsed ear canal requires a meatoplasty to prevent impacted wax forming, to prevent recurrent otitis externa or to allow fitting of an adequate hearing-aid. Operative technique

Normally general anaesthesic (GA),with patient supine, head rotated and supported on a head ring. If the deeper part of the canal is normal and no bone work is required, this procedure can be performed under LA. An endaural split may or may not be necessary for access. The surgical method is not very dissimilar to that of meatoplasty at the time of mastoid surgery. A marking pen isused to plan the size of meatoplasty and infil-

Meatoplasty tration separates the skin from the cartilage in the region of theconchal well.Because only a relatively small meatoplasty is required, a posteriorly based skin flap is the ideal. Cut along the superior and inferior incisions down to cartilage within the conchal well and, using skin hooks for retraction, find the cartilage where it is thick in the posterior part of the concha. The superior and inferior incisions can thenbe followed forwards and medially into the meatus, joining together at the end of themeatalcartilage deep withintheearcanal.The whole posteriorly based skin flap can then be separated from cartilage and lifted out of the way to allow direct access to theexposed cartilage. This can thenbe excised, along with the underlying soft tissue, back to the mastoid cortex bone if required. The skin flap is then repositioned and held in place with a BIPP pack for 2-3 weeks. Meatoplasty for mild meatal stenosis

Indications

Chronic otitis externa, previous ear surgery, previous fracture to theearcanal and radiotherapy may all cause mild meatal stenosis, in which the bony and cartilaginousmeatusarebothnarrowed. Cases of stenosis following radiotherapyshould be considered for surgery as a last resort due to possible the postoperative complication of osteoradionecrosis occurring. In the case of mild meatal stenosis there is normally a small amount of deep meatal migrating skin present and it is therefore unlikely that an external skin flap will be required to be brought into the meatus to provide new skin. Operative technique

An endaural or postaural approach can be used. The endaural approach has the advantage of minimal disturbance to thepinnaposition and allows anapproach directly onto the site of the stenosis so that the cartilaginous and bony meatoplasty canbe seen in direct relationship to each other. After an endaural incision, plan a large posteriorly based conchomeatal flap down towithin 5-8 mm of the annulus.Thisshould be lifted well out of the bony meatus and held away by a small two-pronged selfretaining retractor so that it is not damaged by highspeed drilling for the bony meatoplasty. If there is gross bowing of the anterior canalwall, this should be drilled back first via a separate skin flap lifted off the abnormal anterior canal bone. The skin flap is

29

protected by silver foil during drilling, taking care not to enterthe capsule of thetemporomandibular joint (TMJ). This occurs with ease in meatoplasty following a fractured tympanic ring, particularly if the head of themandiblehas been forced backwardsduringthe injury. The posterior bony meatoplasty should be along the full length of the meatus from annulusto spine of Henle. The latter should always be removed to allow the soft tissues to fall back adequately. It is important to drill from medial to lateral. Drilling can proceed until mastoid air cells are reached but these should not be opened and should ideally be left with a thin-plate of bone over them. Drill witha high-speed cuttingburr, which is irrigated to prevent sequestered bone being left behind, as this will prevent skin growing back over it with any ease. The cartilaginous meatoplasty mustinvolve removing cartilage of the lateral part of the external canal butnot necessarily cartilage of the conchalwell, unless the canal is collapsed at its entrance. The conchomeatal flap is cleared of cartilage and soft tissue and returned to the canal. Any large area of exposed bone can be covered by temporalis fascia, on which the conchomeatal flap then rests, and the flap is held by packing of the canal with BIPP for 2-4 weeks. Meatoplasty for deep and severe meatal stenosis

Indications 1 Conductive hearing loss.

2 Congenital ear anomalies. In these cases there is no deep epithelial skin with migratingproperties and askin flap musttherefore be rotatedintothecanal. Such cases present a difficult challenge to the otologist because: (i) there may be no tissue plane between the tympanic membrane (TM) and the core of scar tissue forming the stenosis; and (ii)there may be abnormalities of the ossicular chain and middle ear cleft, and removing the stenosis of theearcanal may make little difference to the conductive hearing loss. The longer the length of the stenosis, the poorer the prognosis from surgery. Coronal CT scan may be very useful in assessing the length of the stenosis in an ear canal where there areno useful landmarks. The decision to operate is different for unilateral and bilateral cases. In the latter, with a markedbilateral conductive hearing loss, successful meatoplastycanallowthepatient to dispense with hearing-aids. Alternatively, an adequate

30

Chapter 6

ear canal allows a hearing-aid fitting to the ear rather than use of a bone conductor, especially of value if there is also a sensorineural hearing loss. In unilateral cases, patients need to be fully informed about the chances of success and failure. Congenital unilateral cases in children are rarely benefited by surgery. The option of bone-anchored hearing-aids (BAHAs) should be considered before embarking on such surgery, which may require more than one revision for success, particularly if there is also middle ear disease/abnormality. Thecombination of BAHA and bone-anchored prosthetic ear will almost certainly provide a better result than multiple ear operations for congenital meatal atresia with middle ear abnormalities. Operative technique

Endaural or postaural incisions can be used, or these incisions can be joined together to lift the whole pinna inferiorly to allow skin flaps to be rotated in from both in front and behind the pinna (see Fig. 6.4). If the pinna is abnormal, these incisions will have to be modified to the individual case. Skin flaps must be planned to ensure that they are long enough to reach close to the annulus, and thatthey have an adequate base :length ratio so that the tipof the flap does not necrose. They must also allow theresulting defect to be closed in a cosmetically acceptable way. Split skin alone does not do well in severe meatoplasty cases and, toensure asmuch covering of the ear canal as possible, two skin flaps may need to be rotated into the

ear canal. Using the endaural approach, a further flap of skin can be made by using a rotation flap of the conchal well but this seldom reaches the annulus unless some of the lateral meatal skin can be saved. Superiorly based anterior and posterior skin flaps are much thicker than meatal skin even after thinning, so the bony meatoplasty must be performed to its maximum limits to allow the flap to sit in the canal with space for packing. Asharp edge between canal and mastoid cortex should be drilled away so that the skin flap falls smoothly into the ear canal. Once the flaps have been cut and rotated into position, the pinnaneeds to be returned to its normal position. If the pinna covers the skin flap, as inevitably occurs with a posterior flap, then the part of the flap buried by the pinna needs to be de-epithelialised. In the case of an anterior flap, this can often be broughtintoposition betwea theendaural incision, so remaining uncovered. Temporalis fascia can be used to line large areas of exposed bone and will promote epithelialisation from the flap to therest of the canal.The authorprefers to use temporalis fascia asa lining to cover exposed bone rather than a split-skin graft, which rarely ‘takes’ directly over cut bone. Closure, drainage, dressings

Good haemostasis is required to prevent haematoma and secondary infection. A Silastic roll is placed in the canal at the end of theprocedure before packing in order to prevent adhesions developing across the deep

Fig. 6.4 (a) Posteriorly situated superiorly based rotation flap for severe meatal stenosis. (b) Anteriorly situated superiorly based rotation flap with endaural split for severe meatal stenosis.

~ ~ a t o p l a s t y 3I canal. A BIPP pack is inserted firmly into the canal and ideally should be changed underashort GA at 3-4 weeks and replaced with a new pack. This allows the oedema of the skin flaps to settle before repacking with a firmer pack for another 3-4 weeks. If the meatus has not become stable by this time, it is likely that restenosis will occur slowly no matter what is left in the canal to prevent it.

Postoperativ Postoperativeantibioticsshould

be employed in any

case of meatoplasty associated with: (i) extensive cartilage resection; or(ii) infected mastoid cells or cavity. This is in order to prevent perichondritis or cellulitis, both of which increase the likelihood of a stenosis. After removal of thepack,granulation tissue may require local cauterywith silver nitrate. An antibiotic earspray such asOtomise used once daily helps keep the canal free of infection until healing is complete.

Tympanostomy Tube PETER J.ROBB

introduction Theinsertion of tympanostomytubes (‘grommets’) is now the most frequently performed surgical procedure in children in England and Wales. Surgery for serous otitis media (‘glue ear’) should be considered only after failure of conservative management or natural resolution over a period of 3 months or more (Robb, 1993).

indications 1 Chronic secretory otitis media of childhood. Surgery is indicated for persistent effusion confirmed by otoscopy, tympanometry and audiometry: (a) bilateral symptomatic disease persisting for3 months or more with hearing loss 32SdB HL; (b) unilateral or bilateral disease complicated by severe atelectasis, recurrent and/or painful acute otitis media or symptomatic hearing loss (speech, language or learning difficulties); (c) chronic secretory otitis media with underlying sensorineural hearing loss, to facilitate amplification with hearing-aids; (d) cleft lip and palate-at the time of palatal repair. 2 Recurrentacuteotitis media, usually in younger children (c2years at age of onset and often associated with maturational IgA deficiency). Frequent attacks that arepoorlycontrolled by antibiotics,with associated perforation(s),purulentotorrhoeaor febrile seizures may require surgery. 3 Acute otitis media with acute facial nerve palsy due to a dehiscent Fallopian canal, or persistent suppuration, pain and pyrexia despite adequate antibiotic treatment. 4 In adults,serousotitis media may follow an acute suppurativeotitis media or sinusitis or be associated

with allergic or vasomotor rhinitis. It is mandatory to exclude nasopharyngealcarcinomaas an underlying cause of middle ear effusion in an adult: this may necessitate examinationunderanaesthetic (EUA) and biopsy of the nasopharynxat the time of grommet insertion.

Contraindications 1 General considerations including fitness for surgery and for anaesthesia apply. 2 Surgery is contraindicated to an only hearing ear and this should apply to even a minor procedure such as myringotomy and grommet insertion forfear of producing an irreversible hearing loss. 3 Local infection in the external ear canal is a relative contraindication. 4 Anatomical constraints may make grommet insertion impossible if the external meatusis abnormally narrow. If surgery is essential then a postauricular approach to the tympanic membrane (TM) is recommended.

Preoperative management History 1 Severity of symptoms should be assessed with respect to hearing loss, otalgia, recurrent acute otitismedia and speech and language delay. 2 It is important to consider the possibility of a mixed hearing loss, andenquiry relating to the pregnancy, perinatal period and general development is important. A family history of hearing loss should be considered. 3 Associated nasal obstruction, whether due to allergy or adenoidal hypertrophy, is important and will affect

Tymp~nostomyTabe Insertion whether or not surgery to the adenoid or turbinates is appropriate at the time of grommet insertion. Repeated tonsillitis is relevant if the attacks invariably precede documented attacks of acute otitis media. Examination

Examination of theears, nose, throatand neck is followed by pure-tone audiometry (PTA) and tympanometry. For children under the age of about 34 years, hearing assessments may need to be made by distraction testing or conditioning. These facilities are not routinely available in the ENT clinic and referral to an audiology assessment clinic will be required. Hearing assessment may be repeated on more than one occasion over a 3-6-month period to allow spontaneous resolution of the middle ear effusion to occur (Leeds University, 1992). Thresholds greater than 25dE HL in both ears represent a significant loss of hearing in the context of serous otitis media. Tympanometric measurements may show a lack of middle ear compliance witha flat type E reading or marked negative middle ear pressure (type C2 curve). Clinical examination of the nose andpharynx may be supplemented by radiological examination of the postnasal space and sinuses if indicated.

Fig. 7.1 Middle ear anatomy (adapted from Mawson & Ludrnan, 1979).

33

Figure 7.1 depicts diagrammatically a vertical section through the right middle ear cavity to show the structures at risk during myringotomy (Mawson & Ludman, 1979). Figure 7.2 shows the right tympanic membrane(TM) as viewed through the operatingmicroscope ( X10). The myringotomy incision for inserting agrommet in the anteroinferiorquadrant is line ‘a’. Line ‘b’ outlines the incision for aspiration of pus from an acutely infected middle ear. The T M bulges laterally and this is generally the region of maximum dependence. Special care is required to avoid damage to structures as shown in Fig. 7.1.

Operative t Preparation

Anaesthesia For surgery on young children, general anaesthesia is preferred: IV induction is through skin where topical anaesthesia, (e.g. eutectic mixture of local anaesthetics (EMLA) or Ametop), has been applied for the recommended period of time. IV thiopentone or propofol with lignocaine followed by gaseous maintenance with nitrous oxide and oxygen via a laryngeal mask (size 2 or 2.5), using an Ayres T-piece breathing system, is suitable for most children. A recent innovation is the Humphrey’s circuit which meets therequirements of paediatric anaesthesia with intrinsic gas scavenging. A

Fig. 7.2 Right tympanic membrane viewed through microscope (X 10). See text for explanation.

34

Chapter 7

laryngeal mask may not be appropriate for very small children, when a face mask or endotracheal tube will be indicated (Johnston et al., 1990). Routine monitoring of oxygen saturation, end-tidal carbon dioxide, ECG and non-invasive blood-pressure measurements aremade throughout the procedure. Peroperative diclofenac, 1mg/kg is administered rectally asroutine analgesia except where relatively or absolutely contraindicated (e.g. asthma). This regimen is adapted where other procedures are performed under the same anaesthetic; for adenoidectomy, tonsillectomy andother procedures, endotracheal intubation will be required. In adults, a broadly similar technique for induction and maintenance of general anaesthesia is employed. Where no otherprocedure is performed at thesame time, a size 3-4 laryngeal mask is used. A volatile agent is added to the gases for maintenance of anaesthesia, delivered via a circle system withcarbondioxide absorber. Alternatively, continuous IV infusion of propofol 6-10 mg/kg/h may be employed. Peroperative analgesia is with fentanyl 1mcg/kg. Where other procedures are performed under general anaesthesia, intubationwithaRAE-pattern cuffed tube may be necessary. In adultswhennootherprocedure is required, myringotomy and insertion of ventilation tube(VT)may be performed under local anaesthesia with or without sedation. Topical anaesthesia, (e.g. EMLA or Ametop), is applied to the T M and after the recommended period of time a painless myringotomy may be made. In an anxious adult, midazolam or propofol may be administered intravenously to provide sedation, such that verbal contact with the patient is maintained. Continuous IV access and monitoring as for general anaesthesia is recommended if sedation is employed. Prophylactic antibiotics/steroid cover Systemic prophylactic antibiotics are not routinely required.Whereacardiac lesion exists, prophylaxis is recommended as laid down in the British National Formulary (BNF)guidelines. Systemic and topical antibiotics are recornmended postoperativelyfor 1 week if infected middle ear fluidis found at thetime of myringotomy. (These may be modified depending on subsequent bacteriological findings.) Corticosteroid cover may be indicated where systemic steroids have been administered for otherreasons (e.g. asthma) within 6 months prior to surgery. Patient positioning Thepositioning

is the same foradultsand

children,

whether under general or local anaesthesia. The patient is positioned supine on the operating table with the head resting on a head ringto prevent movement. The head is turned away from the operator toprovide the optimum view of the T M withtheoperating microscope. The head should not be turned without the assistance and supervision of the anaesthetist in order to prevent the laryngeal mask or endotracheal tube (ET) from becoming displaced with subsequent hypoxia of the patient. Whereotherproceduresarecarried out underthe same anaesthetic, the insertion of grommets is usually performed first. Operative procedure Figure 7.3 showsthe stages of myringotomy and grommet insertion. With the patient positioned as described above, the T M is viewed with the operationed microscope set at x 10 through an aural speculum. The ear canal is cleaned of wax and skin debris, taking care not to cause trauma or bleeding to the delicate skin of the canal wall. The view obtained is as shown in Fig. 7.2. A disposable myringotome blade is preferred as the sharpness of the blade is guaranteed. A blunt blade will tend to tear and traumatize the TM. Figure 7.3a shows the approach to the T M seen in vertical section. The incision proceeds centroradiallyintheanteroinferior quadrant,takingcarenottoscratchthe middle ear mucosa, which may cause significant bleeding. Following the incision, fluid is aspiratedfromthe middle ear (Fig. 7.3 b), using Zoellner a suction piece with a size l 8 fine end attached. It is not essential to aspirate every last portion of fluid fromtheear, andcontinuous suction may cause bleeding, vacuum damage or noise-induced cochlear damage if prolonged. A Teflon Shepard-patterngrommettubewithout wire is held with aural crocodile-ear forceps so that the grommet is angled with its leading edge pointing forwards (Fig. 7 . 3 ~ ) .At this stage, only the leading edge of thegrommet is placed in themyringotomy 1nclsIon. Thegrommet is then gently manoeuvredintothe incision (Fig. 7.3d), using an Ironside needle. This needle is not too sharp to impale the grommet, but fine enough to gently place the grommet in the incision with the minimum amount of pressure on the TMand ossicular chain. The grommet is then in place, and if necessary, the lumen may be gently cleared of secreti0n.s or blood, using a size 22 fine end attached to the Zoellner suction apparatus (Fig. 7.3e). Finally, a few antibiotic drops may be instilled into

Fig. 7.3 Stages of myringotomy and grommet insertion. See test for explanation.

36

Chapter 7

the ear canal before putting some cotton wool in the meatus (Fig. 7.3f) (Shah, 1991).

Children and adults undergoing grommet surgery are generally fit to be discharged home on theday of operation and to return to normal activities the following day. Avoidance of excess water, particularlyif soapy or dirty, in the ears is advised, although normal swimming without immersion of the head is not prohibited (Pringle, 1992).

1 Injuries to the middle ear structures should be rare and avoidable. Therare dehiscent high jugular bulb should be borne in mind when the T M appears dark or unduly pulsatile. 2 Otorrhoea may be early or late. In the postoperative period,contaminationatthe time of surgery or the presence of infected middle ear fluid may result in discharge. Late otorrhoea may result from an upper respiratory infection, nasal allergy or autoinfection by the child resulting in the growth of nasal, bowel or mixed flora. Immersion in dirty water, especially if the surface tension, has been reduced by soap, may lead to otorrhoea. In adults who have had a grommet inserted following radiotherapy to the neck, earornasopharynx, otorrhoea may be particularly troublesome and difficult to eradicate. Otorrhoea will usually settle with a course of antibiotic ear-drops. While many of these are theoretically ototoxic, evidence suggests that, in the human middle ear with inflamed mucosa, penetration to the inner ear causing sensory hearing loss is extremely unlikely, and most otolaryngologists would recommend ear-drops in this situation (Robb & Johnston, 1991). 3 Where discharge persists despite appropriatetreatment, it is postulated that the grommet may be acting as a foreign body and removal of the grommet is indicated. Granuloma formation, bleeding and polypoid mucosa which herniates through the grommet may complicate the reaction. 4 Sensorineural loss is uncommon following grommet surgery. However, excessive manipulation of the TM, excessive suction and noise from the suction tip may produce a measurable high-frequency loss above 8 kHz. 5 Premature extrusion of the grommet may be due to faulty placement, a blow to the head with dislodgement of the grommet from the TM, or a thin atrophic T M

failing to support the grommet. Usually, however, there is no apparentreason why a grommet extrudesearlier or laterthan average and this is assumed to be due to different individual rates of epithelial growth. 6 Atrophic areas of the TM and myringosclerosis are not uncommon. Myringosclerosis (tympanosclerosis restricted to the TM) is more common when the grommet insertion is traumatic and when bleeding into the T M hasoccurred. Reinsertion of grommets may also increase the incidence of this finding. Generally, myringosclerosis does not have an adverse affect on hearing thresholds. 7 Persistent perforation is unusual except where larger grommets or T-tubes have been used. The incidence can be reduced if the T M edges are freshened and the perforation patched with Gelfoam or fat at the time of tube removal.

Alternative p Serous otitis media may be managed in the short term withantibiotics or decongestants, although neither will produce long-term resolution of effusion in most cases. Nasal allergy should be addressed as part of the overall plan of management. If this coexists, symptoms may improve with antihistamines or nasal steroids or both. Autoinflation of the Eustachian tubes with balloons or other devices may produce short-term improvement. Many younger children find thisa difficult anduncomfortable technique to’master.Long-term compliance with treatment may be poor. Considerationshould be given to other procedures that may improve the long-termbenefits of surgery and, in particular,adenoidectomy (Maw & Herod, 1986). Diathermy to the nasal turbinates, sinus washouts and tonsillectomy may be indicated in a small proportion of children requiring grommets. Long=term ventilation tubes

The indications for the insertion of long-term VTs are even morecontentious than thoseforthestandard grommet. Where standard ventilation tubeshave repeatedly extruded prematurely, or where the otorrhoea of the middle ear (OME) is persistent over many years, the choice of a long-term VT may be justified. In children with craniofacial abnormalities, cleft palate or Down’s syndrome, when the need for longer-term middle ear ventilation can be predicted, then the insertionof a long-term VT as the initial procedure may be appropriate. Inser-

Tympanostomy Tube tion of a long-term VT as a first procedure for uncomplicated cases of OME is not recommended (Mangat et al., 1993). The surgical technique is similar, inserting first one arm of a T-tube andthen the second into the larger than normalmyringotomy incision: there are speciallydesigned T-tube insertors available. The technique of insertion of the Permavent tube is the same as thatfor the standard grommet. Thecomplications include recurrent otorrhoea in over 20% of cases, impacted wax in about 10% and persistent perforation in 20-30% (Hern et al., 1995). The most serious of these is the high persistent perforation rate, which contrasts to a rate of approximately 3% with a standard grommet. The complications of infection and occlusion of the lumen o f the VT may be reduced by using antibioticsteroid drops once a week. The advice regarding water avoidance applies as for standard grommets. There is some disagreement as to whether removing the tubes electively increases or abolishes the persistent perforation rate (Prichard et al., 1992; Hern et al., 1995) and this may relate to the type of tube used. If the tube is still in situ when the child has reached 12 years of age, the likelihood of further middle ear disease (excluding special indications above) is low and the tube should be removed. When removing a long-term tube, the procedure is carried out as a day-case general anaesthetic procedure as for grommet insertion. The edges of the healed myringotomy incision are freshened and the areais filled with sterile cellulose sponge fragments. An overlay technique using fine silastic sheeting may also promote healing of the area (Courteney-Harris et al., 1992). If the perforation persists despite this technique, daycase fat graft myringoplasty (4.v.) should be considered

Insertion

37

as the next procedure and, failing this, formal type 1 tympanoplasty (4.v.).

Acknowledgement The assistance of Dr M.S. Inglis, Consultant Anaesthetist and Director of theDay Surgery Unit, Epsom Healthcare N H S Trust, is acknowledged in the preparation of the anaesthetic protocols in this chapter.

References Courteney-Harris RG, Ford GR, Ganiwalla TMJ & Mangat KS (1992) Closure of tympanicmembraneperforationafterthe removal of Goode-typetympanostomy tubes: the use of silastic sheeting. J . Laryngol. Otol. 106, 960-2. Hern JD, Hasnie A & Shah NS (1995)A long-termreview of the Shah Permavent tube. J . Laryngol. Otol. 109, 277-80. Johnston DF, Wrigley S, Robb PJ & Jones H (1990)The Brain laryngeal mask in paediatric day case anaesthesia. Anaesthesia 45, 924-7. Leeds University (1992)The treatment of persistent glue ear in children. Effective Health Care 4. Mangat KS, Morrison GAJ & Ganniwalla TMJ (1993) T-tubes: a retrospective review of 1274 insertions over a 4-year period. Int. J . Paed. Otorhinolaryngol. 25, 119-25. Maw AR & Herod F (1986) Otoscopic, impedance and audiometric findings in glue ear treated by adenoidectomy and tonsillectomy: a prospective randomised study. Lancet i, 1399-402. Mawson SR & Ludrnan H (1979) Diseases of theEar, 4th edn. London, Edward Arnold, p. 525. Prichard AJN, Marshall J, Skinner DW & Narula AA (1992) Longterm results of Goode’s tympanostomy tubes in children. Int. J , Paed. Otorhinolaryngol. 24, 227-33. Pringle MB (1992) Swimming and grommets. Br. Med. J . 304, 198. Robb PJ (1993) Glue ear: putting the case for surgery. Med. Mon. 6, 67-9. Robb PJ &Johnston DF (1991) Theclinical management of otorrhoea following grommet insertion. Clin. Otolaryngol. 16, 367-70. Shah N (1991) Otitis media and its sequelae. J. Roy. Soc. Med. 84, 581-5.

1 Myringotomy with or without ventilation-tube (VT) insertion. 2 Myringoplasty. 3 Ossiculoplasty including stapes surgery. 4 Excision of small glomus tympanicum tumours. 5 Tympanic neurectomy. 6 Access to theovalandroundwindows in cases of suspected perilymph fistula.

1 Corticalmastoidectomyforacutemastoiditis and drainage of subperiosteal abscess. 2 Cortical mastoidectomy in the treatment of a chronically dischargingtympanicmembrane (TM) perforaa ‘mastoid reservoir’ o f infection is tion, where suspected. 3 Surgical treatment of cholesteatoma. 4 Radical surgery for malignant temporal bone neoplasms. 5 Access to the facial nerve in the temporal bone.

1 Membranous and osseous labyrinthectomy. 2 Endolymphatic sac surgery for Meni6re’s disease, 3 Singular neurectomy and posterior semicircular canal plugging for benign paroxysmal positional vertigo. 4 Cochlear implantation.

1 Removal of acoustic neuromas. 2 Vestibular nerve section for intractable vertigo.

A recent pure-tone audiogram (PTA) must be available priorto anysurgical approach to the middleear or mastoid. This is to enable postoperative changes in the hearing level to be quantified, and to accurately assess cochlear function prior to surgery. For elective surgery any active infection in the earcanalskin, middle ear or mastoidmust receive prior medical treatment. Informedconsentmust be obtained. The nature of any discussions with patients or relatives will depend on the exact surgical procedure undertaken. Itis important when discussing success rates and complications of operations to relateto one’s own surgical experience rather than that cited in the medical literature. The requirements for preoperative imaging will depend on the procedure undertaken. CT is the investigation of choice in delineating middle ear and mastoid pathology. For the majority of cases, however, preoperative imaging is not required.

The pinna is based on a framework o f elastic cartilage thrown intofolds. Medially the cartilage is prolonged as a tube forming the cartilaginous portion of the external auditory canal (EAC). Attachment of this cartilage to the underlying bone stabilises the pinna in position.

Approaches to the ~ i d d l Ear e and The underlying temporal bone iscornposed of four parts:squamous,petromastoid,tympanicand styloid (Fig. 8.1). Onthe lateral surfaceof the temporal boneat the posterosuperior limit of the bony external canalis a depression known as the suprameatal triangle (of MacEwen),which lies 1Smm lateral to themastoid antrum in the adult. The anterior borderof this triangle is usually marked by a projection (Henle's spine). The EAC in the adult is 24mm long and is composed of a lateral cartilaginous part and a medial bony part. The meatal cartilage forms a gutter with its roof formed by fibrous tissue. Likewise thetympanicbone is Cshaped in cross-section with a gap superiorly formed by the squamous and petrousbones. The canal is S-shaped, withthecartilaginous part directed posterosuperiorly and thebony part directed anteroinferiorly,The T M lies at the medial limit of the external canal and lies obliquely at 55" to the anterior canal wall, whichasa result islonger than theposterior wall. A prominent bony anterior canal wall can often obscure the anterior portion of the TM. Theskin of the cartilaginous canalis hair-bearing and contains ceruminous glands. The skin covering thebonycanal is thin andadherent to the underlying bone. The T M is composed of two parts: the pars tensaand the pars flaccida. The pars tensa forms the inferior part of the membrane and is composed of a thin outer layer of squamousepitheliumand an innermucosal layer. Sandwichedbetween these layers is a layer of fibrous tissue. The medial surface of the pars tensa is adherent to thehandle of the malleus. The pars tensais thickened

ast to id

39

at its circumference as the annulus tympanicum, which inserts into a groove in the tympanic plate. The pars flaccida is thicker and is morphologically identical to deep ear-canal skin. The physiological process of lateral epithelialmigrationacts to keep thecanal free of squamous epithelial debris. The sensory nerve supply to the pinna, external canal and T M is derived from the Vth, VIIth, IXth and Xth cranial nerves, and from the cervical plexus (C2 and C3). The exact distribution of these nerves is variable.

nae§the§ia

Local or general anaesthesia maybe used; the method o f choice will depend on the suitability of the patient, the preference of the surgeon and the availability of hypotensive general anaesthesia, For procedures under local anaesthetic (LA) use a combination of infiltration and topical application ofLA. The soft tissues around the pinna (depending on the site of any incision) and the ear-canalskinare infiltrated witha 2% lignocaine/ 1:80 000 adrenaline mixture. To anaesthetise the middle ea: mucosa,cotton-wool balls soaked in 4% lignocaine solution are applieddirectly. An. intramuscular injection of Omnopon can be given 20min prior to surgery to provide additional analgesia. atient ~o§itionin

The patient is positioned supine on the operating table, with reverse Trendelenburgtilt and extension o f the neck. The head is turned away from the surgeon, with the operated ear uppermost. It is o f prime importance that thesurgeon adopts a comfortable sitting positionin relation to the patient. Skin ~ r e ~ a r a t i o n

Mastoid process

/

""t.2,

Fig. 8.1 Lateral surface of the right temporal bone.

Shaving of the skin around the ear may be necessary. Theamount shaved will depend onthe site of the incision and should be the responsibility o f the surgeon. Theearcanaland middle earare physiologically contaminated sites and eradication of all microorganisms is neither possible nor desirable. Skin preparationshould be with anaqueous solution,suchas povidone-iodine,

qa

Chapter 8

The approachchosen by the otologist is governed by the procedure being undertaken and personal preference. Surgical procedures on the middle ear cavity, where theearcanal is sufficiently wide, can be undertaken permeatally. Wheretheearcanal is narrow,both endaural and postaural approaches can be adapted to provide access to the middle ear. Most otologists use a postaural approach for procedures involving the mastoid air-cell system. An endaural approach can, however, be used to provide access to this area. Permeatal approach. -posterior tympanomeatal flap

1 The EAC and TM are inspected with the operating microscope and the largest aural speculum which the canal will accommodate is inserted. Shea speculae are suitable and the canal should accommodate aminimum 6mm speculum size. A speculum holder can be used to facilitate working with both hands simultaneously. The canal is cleared o f epithelial debris. 2 The canal skin is infiltrated with LA to reduce bleeding and facilitate dissection. A single injection of approximately 1m1 of solution isgiven slowly into the posteriorcanal wall at thejunction of the bony and cartilaginous canal (this corresponds to the medial extent of the canal-skin hairs). 3 An incision is madeintothecanal skin downto the bone. A two-limbed incision is preferred (Fig. 8.2).

Fig. 8.2 Endorneatal skin incision for a right posterior tyrnpanorneatal flap.

Fig. 8.3 Middle ear structures revealed through a right posterior tympanorneatal flap.

The transverse component is madewitha Lumsden knife and passes from superior to inferior. The incision remains parallel to the annulus, having to pass more medially in the inferior part of the canal. The longitudinalcomponent is madewitha Plester knife and microscissors, and passes from the superior extentof the transverse incision medially along the posterosuperior canal wall towards the pars flaccida. 4 The canal-skin flap is elevated using an elevator and narrow suction tip if necessary (the canal skin must be protected from the sucker). The dissection may be facilitated by the use of a cotton-wool ball impregnated with 1:1000 adrenaline, placed against the skin flap. The skin of the superior bony canal is relatively thick and dissection should commence here and subsequently progress medially and inferiorly. There may be some tethering of skin to the underlying tympanomastoid suture, and care must be taken to avoid tearing the skin flap in this location. Likewise, the skin over the inferior bony canal is extremely thin and easily torn. 5 The dissection continues medially until the annulus tympanicum is identified. The annulusis then dislocated from its groove superiorly, using a dissector such as a Hough elevator, and the middle ear is entered, by dividing the middle ear mucosa with a sharp needle. Using a drum elevator (e.g. Rosen’s) the annulus is dislocated inferiorly and anteriorly, allowing the tympanomeatal flap to be reflected anteriorly and giving access to the middle ear (Fig. 8.3).

Approaches to theMiddleEarandMastoid

41

6 When access to the posterior mesotympanum is required,thechordatympani nerve can be reflected inferiorly. This canbe facilitated by identifying the canal for the chorda tympani,and with a sharp pick removing bone, allowing the nerve to exit the bony canal at a more inferior position. Endaural approach

1 The endaural incision utilises the notch between the cartilages of the tragus and helix. The EAC is infiltrated with LA and adrenaline, as in the permeatal approach to the middle ear.Additionalinfiltration is inserted between the tragus and helix, and also superiorly anterior to the helix. 2 The size of theendaural incision depends onthe procedure being undertaken (Fig. 8.4). If the incision is being used to facilitate access to the middle ear,for example during stapedectomy, asmall endaural incision is required. If a portion of temporalis fascia is required for T M reconstruction, the endaural incision may be extended superiorly. Finally, some surgeons who use the endaural approach formastoidectomy surgery will carry the incision around the top of the pinna, allowing the pinna to be reflected inferiorly to allow access to the mastoid cortex. 3 The incision is facilitated by the use of a Lempert’s endaural speculum, and is made using a scalpel with a size 15 blade. The incision commences in the superior

Fig. 8.5 Endaural incision deepened to expose the temporalis fascia and external bony canal.

part of “thebony external canal, incising the skin down to bone. The incision then passes superiorly and laterally between the tragus and helix. Deepening the incision anterior tothe helix gives excellent exposure of the temporalis fascia, which may be harvested. The tragal cartilage and perichondrium may also be exposed and segments removed forsubsequent middle ear reconstruction. 4 The incised skin in the superolateral part of the bony external canal may now be elevated with a Lempert’s periosteal elevator to improve visualisation of the deep canal and TM (Fig. 8.5).At this stage, self-retaining retractors are inserted and, using microsurgical instruments,meatal skin incisions aremade,as in the permeatal approach to the middle ear. Postaural approach

Fig. 8.4 Endaural skin incision.

1 A ‘hockey-stick’-shaped postaural incision (Fig. 8.6) is made, with the inferior extension passing approximately 5mm behind thepostauricular crease. The superior part of the incision passes over the top of the pinna, facilitating access to the anterior epitympanum and zygomatic cells during mastoid surgery. In infants the mastoid process is relatively undeveloped, leaving the facial nerve at the stylomastoid foramen unprotected by bone. As a result the postaural incision in infants

Fig. 8.6 ‘Hockey-stick’ postaural incision.

bloodless plane, the dissection proceeds inferiorly to expose the periosteum over themastoid process and anteriorly towards the cartilaginous EAC. 3 The next stage of the approach is dependent on the surgical procedure being undertaken.Optionsareas follows: (a) A portion of temporalis fascia can be taken to use as a graft during subsequent T M reconstruction. (b) The periosteum over the mastoid cortex may be incised and elevated to allow access for mastoidectomy surgery. A T-shaped periosteal incision provides excellent access for this purpose (Fig. 8.8). (c) The approach may proceed anteriorly, elevating of the EAC. The canal the skin from the posterior part skin may be incised posteriorly to enter the lumen of the canal. The remainder of the canal skin may be elevated medially asatympanomeatal flap to gain access to the middle ear. (d) A skin flap from the external canal may be dissected to facilitate meatoplastyduring open-cavity mastoidectomy surgery.

Surgical packing of the external ear canal is a routine part of most approaches to the middle ear and mastoid.

Fig. 8.7 High postaural incision in infants.

must be situated high and posteriorly, approaching the mastoid cortex away from the facial nerve (Fig. 8.7). 2 The incision is deepened superiorly until the temporalis fascia is identified. Staying in this relatively

Fig. 8.8 Postaural approach exposing temporalis fascia and mastoid cortex with T-shaped periosteal incision.

Approaches to theMiddle EarandMastoid The purpose of packing is to retain a tympanomeatal flap in position, to secure haemostasis and to act as an antiseptic. The packing used will depend on personal preference. The author uses nylon strips, cotton-wool balls and ribbon gauze impregnatedwithbismuth, iodoform and paraffin paste (BIPP). This packing remains in situ for 1-2 weeks. Incisions for otosurgery are closed in two layers with interrupted sutures. The use of a wound drain is not necessary. A pressure bandage is applied for 24 h where an external incision has been made.

Following any surgical procedure on the middle ear or mastoid the integrity of the facial nerve and cochlear function must be ascertained. The presence of a cochlear reserve in the operated ear can be crudely assessed by the Weber test; if there is doubt, however, a masked bone-conduction audiogram should be obtained.

The complications of specific procedures will be dealt

43

with elsewhere. The following complications can occur after any surgical procedure on the middle ear or mastoid. 1 Haemorrhage from an incision. 2 Wound haematoma. 3 Wound infection with possible perichondritis of the pinna. 4 Sensitivity to aural packing. 5 Loss of cutaneous sensation around the ear following external incisions, due to interruption of sensory nerve supply. This is usually temporary, with sensation recovering after a period of weeks.

Further rea Ludrnan H (1988) Mawson’s Diseases of the Ear, 5th edn. London, Edward Arnold. Tos M (1993) Manual of Middle Ear Surgery, Vols 1 and 2, 1st edn. Stuttgart, Thierne.

ri PETER-JOHN WORMAL

4 What is the state of the other ear? Usually the worst ear is operated on first. Is it possible to bring the operated ear to within 1.5dB of the other ear, or better than the other ear? If, after surgery, the air-conduction gap between the ears is greater than 1.5dB, the patient will not notice any air-bone gap closure that may have been achieved (Browning et al., 1991). 5 Has there been previous ear surgery? Repeat surgery is more difficult and requires an experienced surgeon. 6 Are there any associated ENT complaints, e.g. nasal stuffinesddischarge?Postnasal space pathologymay contribute to Eustachian tube dysfunction.

Surgical closure of the tympanic membrane (TM) without ossicular reconstruction.

1 Closure of the air-bone gap in perforated eardrum to within 1.5dB of the other ear. 2 Prevention of recurrent otorrhoea.

1 Age 8 years if other ear has normal hearing threshold (Koch et al., 1990). For children with bilateral conductive hearing loss and inactive ears, surgery may be considered fromschool-going age if the compliance with wearing a hearing-aid is low. 2 Active otorrhoea at the time of surgerylowersthe success rate. 3 It is inadvisable to put an only hearing ear at risk. 4 The presence of skin in the middle earoronthe underside of the T M which is not accessible or is impossible to remove.

Examinatio

1 Position and sizeof the perforation as a percentage of the TM. Anteriorperforationsmay be better approached via a postauricular incision to enable the anterior rim of the perforation to be visualised. Large and subtotal perforations are technically more difficult. Can the rim of the perforation be fully visualised or will a bony canal wall prominence need to be removed for visualisation at the time of surgery? If so, a drill will need to be requested for the operating tray. 2 Ensure there is no associated disease in theear, such as cholesteatoma, so that appropriate surgery is performed. 3 Is the ear active and does the patient need treatment (aural toilet,ear-dropsand systemic antibiotics) to render the ear inactive before surgery? 4 Eustachiantubepatency is no longer considered to influence the success rate of myringoplasty (Reimer et al., 1988; Sloth & Lildholdt, 1989; Jonathan, 1990). 5 What is the state of the other ear? Is the worst ear

1 Is otorrhoea present and for how long has the ear been discharging? 2 Is the patient deaf and for how long has this been noticed? 3 Is there associated vertigo or tinnitus? If present, one should look for other pathology such as cholesteatoma. 44

~ y ~ i n g o ~ l ~ s4t5y being operated on? Is the other ear infected and does it need appropriate treatment? 6 Do tuning-fork tests confirm the presence of conductive deafness? A sensorineural deafness cannot be improved by myringoplasty. 7 The rest of the ENT system needs a thorough examination to exclude associated nasal or postnasal space disease and potential causes for referred otological symptoms.

Pure-tone audiogram

The pure-tone audiogram (PTA) is needed to confirm the presence and degree of the conductive deafness and to allow comparison with the other ear. The PTA also documents, for medicolegal reasons, the state of the ear preoperatively andthus should have been performed within 3 months of the operation.

canal is usually prominent and can often obscure the anterior edge of a perforation.

The T M consists of two parts: a pars tensa and a pars flaccida. 1 The pars tensa consists of three layers: an outer layer of squamous epithelium (skin), a middle fibrous layer withboth circular and radial fibres andan inner mucosal layer (cuboidal epithelium). 2 The pars flaccida consists of the squamous .epithelial layer and mucosal membrane,but lacks the intrinsic strength of the pars tensa as the fibres of the fibrous layer are randomly orientated. 3 The relevant surgical landmarks are presented in Fig. 9.1.

Operative technique Preparation Anaesthesia

The external canalconsists of a cartilaginous outer third and bony two-thirds. 1 Thecartilaginouscanal.The cartilage of theouter canal does not form a complete ring, with a defect at 1 o'clock, just anterior to the base of the helix of the ear where the endaural incision can be made. 2 The bony canal.Theanteriorportion of the bony

General anaesthetic This is the most commonly used method. A controlled induction and relatively slow pulse will give agood operative field. To improve the field, infiltration with a combination. of local anaesthetic (LA) and adrenaline/ vasopressin into the incision area and the bony external canal should be performed. The syringes drawn in solid lines in Fig. 9.2 indicate these infiltration points.

Local anaesthetic

Fig. 9.1 Diagram of the tympanic membrane and its surgical landmarks.

This operation is eminently suitable for LA and mild sedation. This is especially true when general anaesthesia carries a risk due to underlying systemic disease. The nature of the LA and operation needs to be carefully explained to the patient as some patients may not tolerate LA. The following LAs are used: 1 0.5% Bupivicaine (toxic dose 3mglkg) with 1:200 000 adrenaline; 2 1 or 2% Lignocaine (toxic dose 3-5 mglkg) with either 1:80 000 or 1:200 000 adrenaline; 3 synthetic vasopressin may be substituted for adrenaline in a concentration of l :20000 or l :50000 where anaesthetic risks preclude the use of adrenaline. Sedation withashort-acting benzodiazepines, such as midazolam, is necessary. An initial dose of 5mg is

46

Chapter 9 ring should be placed underthehead.Theshoulder support creates thecorrect angle between head and neck, allowing rotation of the head away from the surgeon, for the TM to lie at right angles to the surgeon. This prevents the surgeon from leaning on the patient's chest when working on the superior part of the eardrum. Thepatientshould also be placed in theantiTrendelenberg position as this improves venous drainage and creates a better operating field.

Postauricular incision (Fig. 9.3)

This is the incision of choice when there is a large or anterior perforation of the TM. It also gives easy access to autologous temporalis fascia. Endaural incision (Fig. 9.3) Fig. 9.2 Diagram o f the local anaesthetic and vasoconstrictor infiltration needed for general (solid lines) and local anaesthetic (solid and dotted lines).

given, which can be topped up by three 2mg doses as required to a maximum of 11mg for a 70 kg adult. The syringe drawn in dotted lines in Fig. 9.2 represents theadditionalinfiltration needed for complete anaesthesia of the ear for myringoplasty by either the endaural or the postauricular approach.

A smaller incision appropriate to central or posterior perforations.

1 Infiltration of vasoconstrictor and LA (Fig. 9.2). 2 Inspection of the external canal and T M of the ear with microsuction. This allows appreciation of the per-

Prophylactic antibiotics

Inthe inactive uninfected ear, systemic prophylactic antibiotics do not influence the success rate of myringoplasty or the audiometric outcome (John et al., 1988). If the ear is active, the surgery should be postponed until the activity is controlled. If this cannot be achieved, a corticalmastoidectomy should be performed and adequate drainage established between the middle ear and the mastoid via either a superior or a posterior tympanotomy prior to the myringoplasty being done. The ear should be prepared for surgery by wiping the ear and surrounding area with a solution of iodine and water. Alcohol and chlorhexidine should be avoided as they may be toxic to the inner ear. Patient positioning

The patient should be positioned on hidherback with a shoulder support elevating the shoulders 5cm. A head

Fig. 9.3 Diagram demonstrating the postauricular and endaural incisions.

~yr~ngopl#sty 47 foration position and canal protuberances, which may influence choice of incision. 3 If a postauricular approachis chosen, a Rosen’s elevator is used to incise theposteriorcanal wall 10mm abovetheannulus.Thismarksthe place wherethe externalcanal-wall skin will be incised duringthe postauricular approach. 4 The chosen incision is performed. The postauricular approach

1 The incision as shown in Fig. 9.3 is performed, the posterior auricular muscles are cut andthe loose areolar layer above the temporalis muscle is identified. With a scalpel, the softtissues are cut up to the posterior border of the external ear canal, without the canal being entered (Fig. 9.4). A blunt double hook is used to elevate the skin, allowing the dissection to be continued superiorly, keeping in the plane superficial to the temporalis muscle. A 4 X 5 cm area of the temporalis muscle is exposed (Fig. 9.4). Using an 11 blade, a 3 X 4 cm area of fascia is incised. The edge of the fascia is elevated with forceps and, with blunt dissecting scissors, the fascia is removed. 2 A scalpel is used to create a soft-tissue flap by incising throughtheperiosteumontothe skull (Fig. 9.4). When sutured, this flap will pull the attached postauricular external canal skin against the bony posterior canal wall. This soft-tissue flap is elevated forward with a periosteal elevator until the spine of Henle is visualised. The soft tissues are dissected free from the

Fig. 9.5 Diagram of postauricular approach with visualisation of the entire tympanic membrane.

spine and, using a canal-wall elevator, the skin of the posterior canal wall is pushed anteriorly until the incision made earlier with the Rosen’s elevator is seen. 3 An 11 scalpel blade is used to continue the incision in the posterior canal-wall skin in a U shape both superiorly and inferiorly, transecting two-thirds of the circumference of the external canal. 4 A self-retaining two-pronged retractor is positioned to hold the outer part of the ear canal and the pinna forward. A second self-retaining retractor is positioned at right angles to holdthesuperiorand inferior soft tissue awayfromtheearcanal. If the microscope is positioned above the partially severed external canal, the bony external canal and entire T M should be seen (Fig. 9.5). Adequate exposure is essential. Without full visualisation of the TM,the chances of success diminish and the incidence of complications rises. If the bony canal wall obstructs part of the T M perforation and visualisation cannot be obtained by rotatingthepatient’s head, then this prominence needs to be removed with a drill or curette until full visualisation is achieved. The endaural approach

Fig. 9.4 Diagram of the postauricular approach and periosteally based soft-tissue flap.

Theendaural incision isbest performed with an 11 blade, as shown in Fig. 9.3, ensuring that the periosteum is incised. A self-retaining two-pronged retractor is inserted and theexternalcanalopenedas widely as possible. The loose areolar layer lying superfi-

48

Chapter 9

cia1 to the temporalis muscle is identified. A blunt double hook is used to elevate theskin, allowing easier access to this layer. A 4 X 5 cm area of temporalis muscle is exposed. Using an 11 blade, a 3 X 4 cm area of fascia is incised. The edge of the fascia is elevated with forceps and blunt dissecting scissors and the fascia is removed. The self-retaining retractorsare repositioned andadequate visualisation of the T M is ensured. If the anterior edge of the perforation is not visible, the endaural incision should be extended to allow the self-retaining retractor to pull thepinnamore posteriorly. If further exposure is needed, the posterior canal-wall skin lying lateral to the incision is mobilised subperiosteally in the posteroinferior direction. This allows a better angle of vision and more of the anterior T M can be visualised (Fig. 9.6). Preparation of the temporalis fascia autologous graft

at ‘6 o‘clock’ ~~

The temporalis fascia graft is placed on a glass slide and compressed withaswab to remove excess moisture from the graft. One end of the graft is held with the swab while the graft is spread and fat and muscle removed with a scalpel (11 blade). This procedure is repeated until the entire graft is cleaned of excess tissue. The graft is allowed to air-dry on the slide. Tympanic membrane and middle ear preparation.

The edge of the perforation is excised with a curved

Fig. 9.7 Diagram of the incisions for the posterior canal-wall flap.

needle until the fibrous middle layer of the TIM is seen. The mucocutaneous junction needs to be broken along theentire circumference of theperforation. A sickle knife is used to denude the undersurface of the TM, creating a raw bed for the graft. Care needs to be taken to ensure that the incudostapedial joint is not touched and that excessive movement of the malleus does not occur. The edges of the perforation should be everted to exclude and remove, if present, ingrowth of squamous epithelium. The posterior canal-wall flap

Fig. 9.6 Diagram of endaural approach with extended incision and posterior flap mobilisation to improve anterior tympanic membrane exposure.

The superior incision is started at 2 o’clock and angled on tothe posterior canalwall to join the horizontal limb of the posterior incision. The inferior limb is started at 6 o’clock and angled on to the posterior canal wall (Fig. 9.7). Theflap is raised along as wide an area as possible with a Rosen’s elevator. Care should be taken not to apply suction to the flap as this could cause tearing of the flap. The suction tip can be placed either on the flat portion of the elevator or on a cotton-wool ball placed on the elevated portion of the flap. The annulus of the T M is identified and elevated out of its bony groove. This is best done at 8 o’clock, as this is below the incudostapedial joint and the chorda tympani. The annulus is gently pushed forward and the chorda tympani identified and preserved. A canal-wall elevator is used to elevate the annulus to 6 o’clock inferiorly and

~ y ~ i n ~ o p l a s t y49 asfarasthe neck of the malleus superiorly. The incudostapedial jointis identified and the mobilityof the ossicular chain is checked by carefulmovement of the handle of the malleus. A wide exposure of the middle ear is mandatory to ensure easy and precise placement of thegraft. Most technical difficulties and resultant graft failures occur due to inadequate exposure at this step. Placing of the graft

Placing continuous traction on the graft, an 11 blade isused to elevate the graft from the glass slide. The graft is trimmed to the correct size with a pair of fine scissors. The graft shouldbe larger than the perforation by 3mm on all sides. It is better to use a slightly larger than a smaller graft to ensure complete closure of the perforation. Small pieces of Spongistan areplaced under the perforation edges to support the graft. The posterior flap is elevated forward and the graftis placed underthe TM. The graft isplaced underthe handle of the malleus but,wherethere is a large anterosuperior perforation, it may be placed lateral to the malleus if the drum remnants have been removed fromthehandle(Stage & Bak-Pedersen, 1992). If epithelial remnants remain, a cholesteatoma pearl may result. The posterior flap is replaced and the position of the graftchecked. A canal-wall elevatoror similar bluntended instrumentis used to ensure that the graft is under all edges of the perforation. The instrument should be placed underthe TM edge andsweptsuperiorly or inferiorly rather than poked in and out as this action may pull the graft out as the instrumentis removed. Overcoming the anterior-based perforation

An anterior perforation which abuts the anterior canal wall or has a narrow rim can be overcome by using the tuck-through-tail methodof additional support.Using a Rosen’s elevator, an incision is made in theanterior canal-wallskinabovetheannulus and abovethe Eustachian tube orifice. The annulus is elevated and the middle ear mucosa in the entrance to the Eustachian tube perforated. The pocket is widened sufficiently to allow passage of a thin suction tip into the Eustachian tube. Before the graftis placed, the anteriormillimetre is partially removed and formed into a tail attached to the anterior edge of the graft. This is moistened and rolled between the fingers to formatail (Fig. 9.8).Using crocodile forceps, the graftis placed with this tail down theEustachiantube. The thin sucker tip is placed

Fig. 9.8 Diagram for the creation of a tail on the graft and the incision for the anterior canal-wall pocket for sucker tip and graft tail.

through the anterior canal-wall pocket down the Eustachian tube and the tail is sucked into the sucker tip. The tip is withdrawn with the tail until the graft is firmly seatedundertheanteriorannulus.Additional support maybe requiredwithSpongistanalongthe superior and inferior borders of the perforation. Once the remainder of the graft is correctly positioned, the excess tail is removed with microscissors lateral to the annulus. This method overcomes anterior graft failure due to lack of support of the anterior graft edge. Inadequate technique when dealing with anterior-based perforations is the most common cause of immediate graft failure(Jurovitzki tic Sade, 1988; Sharp et al., 1992; Vartiainen, 1993). External canal packing

A thin sheet of Silastic with a circular end, 8-10 mm wide and 3 cm long, is inserted on to the T M graft without disturbing its position. The Silastic should rest on theT M remnant rather than on the graft alone. Two 1cm pieces of gauzeimpregnatedwithbismuth, iodoform andparaffin paste (BIPP)are rolled and placed withacrocodileforceps ontothe Silastic sheeting, ensuring even, moderatepressure on theentiregraft. These small pieces of BIPP allow better visualisation of the graft during placement of the packing, which decreases the chanceof disturbing the positionof the graft. The incision is closed before a final 3cm strip ofBIPP

gauze is placed in the remaining external canal. Alternate formsof packing arepieces of Spongistan soakedin gentamycin and hydrocortisone solution or gentamycin and hydrocortisone ointment appliedon tothe graft and filling the external canal. Wound closure

Postauricular wound The soft-tissueflap is suturedwith3/0 vicryl or 210 chromic. By replacing this flap, the posterior canal-wall skin attachedto the flap is pulled firmly against the bony posterior canal wall. An interrupted subcutaneous layer of sutures is added, followed by continuous a subcuticularsuture, using thesamesuturematerial throughout.

reperforations maybe without infection.

due to graftatrophy with or

The incidence of deadearsaftertympanoplastyhas decreased since surgeons have avoided using alcohol and chlorhexidine as an antiseptic. However, sensorineuralhearing loss, especially in the high frequencies, can occur as result a of excessive manipulation of the ossicular chain. SS

A conductive hearing loss may persist despite closure of the perforation if ossicular adhesions or discontinuity was present at surgery or occurred after surgery.

Endaural wound Depending on the length of the incision, either one or two deep mattress sutures with 210 nylon are sufficient for closure.

These arecaused by buryingkeratinisingepithelium under the graft. They are usually visible through theT M or graft and may need excision.

A mastoid dressing is appliedfor 24 h. Thisshould include support of the ear posteriorly with cotton wool as this is more comfortable for the patient. The Weber tuning-fork test is performed prior to discharge to exclude a dead ear. The patient is instructed to wash his/ her hair after 3 days without allowing water into the ear. This can be prevented by placing cotton wool covered with Vaseline in the conchal bowl. Endaural sutures are removed after 5 days. Postauricular sutures do not require removal as they are subcuticular. The patient is seen in the out-patients 3 weeks after the operation when theBIPP gauze and silastic are removed under the microscope. If complete healing has not occurred, a 5-day course of gentamycin and steroid drops is prescribed. The patient is reviewed 3 months later and a repeat PTA performed.

Canalstenosis may occurfromcontracture of the wound when an endauralincision has been used. This is rarely seen with a postauricular incision.

Complicati Graft failure

A complete graft take rate of 80% or better should be expected.Immediategraftfailuresare usually due to technical faults, with the most common area of failure been the anterior edge of the perforation. Late

Total replacement of the T M by a harvested homograft cadaver TM has been successfully used in Europe. Legislation regarding the useof homograft tissues differs widely from countryto country. The risk of transferring diseases such as Jakob-Creutzfeld slow virus and HIV appears small but is none the less present. An alternative to homograft replacementof the T M in total perforationsis utilisation of formalised autologous temporalis fascia. The fascia is draped over a mould of the T M and external canal. The fascia is placed in 4 % formalin for 3min and washed in saline for a further 9 min before beingallowed to dry. After removal of deep canal-wall skinand TM, the graft is placed on the handle of the malleus and pressed into the bony annulus. It is supported by Spongistan in the middle ear and packing in the external ear (Pfleiderer & Moffat, 1988).

Transcanal myringo

This procedure may be used for small central perforations with minimal air-bone gap. The temporalis fascia is taken through a separate incision behind the ear and prepared as described. The middle ear is prepared as described. Spongistan is placed in the middle ear and the graft is pushed through the perforation onto the bed of Spongistan. Apposition of the graft to the perforation edges is ensured and the canal is packed as described. The ossicular chaincannot be examined whenusing this approach.

References Browning G, Gatehouse S & Swan I (1991) TheGlasgow Benefit Plot: a new methodforreporting benefits from middle ear surgery. Laryngoscope 101, 180-5. John D, Carlin W, Lesser T, Carrick D & Fielder C (1988) Tympanoplasty surgery and prophylactic antibiotics: surgical results. Clin. Otolaryngol. 13, 205-7.

Jonathan D (1990) The predictive value of Eustachian tube function (measured with sonotubometry) in the successful outcome of myringoplasty. Clin. Otolaryngol. 15, 431-4. Jurovitzki I& Sade J (1988) Myringoplasty: long-term follow-up. Am. J . Otol. 9, 52-5. Koch ‘W,Friedman E & McGill T (1990) Tympanoplasty in children: the Boston Children’s Hospital experience. Arch.Otolaryngol. Head Neck Surg. 116, 35-40. Pfleiderer A & Moffat D (1988) Thefasciaform graft: a technique for repair of large perforations of thetympanicmembrane. Clin. Otolaryngol. 13, 427-34. Reimer A, Andreasson L, Harris S & Ivarsson A (1988) Predictive value of tubal function, Valsalva’s manoeuvre and volume of ear spaces. Acta Otolaryngol. (Stockholm) 499 (Suppl.), 127-30. Sharp J, Terzis T & Robinson J (1992)Myringoplasty for the anterior perforation: experience with the Kerr flap. J . Laryngol. Otol. 106, 14-16. Sloth H & Lildholdt T (1989) Tests of Eustachian tube function and ear surgery. Clin. Otolaryngol. 14, 227-30. Stage J & Bak-Pedersen K (1992) Underlay tympanoplasty with the graft lateral to the malleus handle. Clin. Otolaryngol. 17, 6-9. VartiainenE (1993) Findings in revision myringoplasty. Ear Nose Throat J . 72, 201-4.

S ANTONY A. NARULA

Reconstructive surgery of the middle ear toimprove the conduction mechanisms.

1 This should never be performed in an only hearing ear and rarely in an ear which is the better hearing ear. 2, Ossiculoplasty should not usually be performed at the same time as conservative cholesteatoma surgery, but at a later stage. 3 Reconstruction in the presence of active infection is generally not advised.

only a small percentage of the sound energy in normal speech is above 2 kHz, a significant proportion of comprehension resides inthe higher frequencies. This is especially important as inexpert or clumsy intervention can lead to a high-frequency sensorineural deafness even if the air-bone gaphas beenclosed forthe 'classic' speech frequencies of 500, 1000 and 2000 Hz. Occasionally it may be appropriate to offer reconstruction in a patient whose hearing thresholds are so low that the surgery isreally an attempt to provide better thresholds precisely forthepurpose of better hearing-aid fitment.

perative tec Preparation

Audiological evaluation is the most important element of assessment. Inany case, with bilateral conductive deafness great care needs to be taken in performing the pure-tone audiogram (PTA), as accurate masking may bedifficult to achieve. A masked speech audiogram should also be available, and tympanometry (otoimittance) can help to avoid occasional errorsabout middle-ear effusion and toconfirm ossicular discontinuity. The surgeon also needs to be familiar withthe psychoacoustics of binaural hearing and help the patient to realise that, if the operated ear is to provide useful binaural hearing, it must come up to within no less than 1.5-20 dB of the unoperated (i.e. better) ear. In anycase, wherethepatient is unsure about proceeding there should be an opportunity to try a hearing-aid. The problem of which frequencies of the PTA should be evaluated- both before and after surgery-remains controversial. Itmust be remembered that, although

In the IJK most procedures are performed under general anaesthetic (GA)with hypotension. Local infiltration of theearcanalwith a combination of lignocaine/l in 80000 adrenaline and IV sedation are a perfectly feasible alternative but require experience. The patient is supine with the head turned away from the surgeon. A head-up tilt of 15-20" is helpful and the patient should be secured to the operating table in case tilting is required. Antibiotics and otherprophylactic drugs are not needed. incision

Endaural, permeatal or postaural approach according to preference (see Chapter 8).

Ossiculoplasty

53

ossicular replacements. It has goodbiocompatibility but long-term results are not yet available. At present the author considers preformedhydroxylapatite devices (for example, Fig. 10.1)to be the easiest to use and stable over long periods. There are many different designs, according to the individual’s preferences, and they are also available now in combination with wire and plastipore to provide more malleability. These newer ones are easy to adjust, as they can be cut instead of drilled, but their long-term stability is not yet well established. Fig. 10.1 Ceramic preformed prosthesis (Applebaum type). (With permission from Smith & Nephew Surgical Limited.)

Clinical problems

Eroded long process of incus Special considerations

The surgeon needs to be familiar withthe range of available biomaterials. 1 Autograft bone. This may be the remains of ossicle (usually an erodedincus) or a piece of cortical bone from the squamosa. Ithas the advantages of being available, reliable and biocompatible. The use of homograft bone from another donor is to be discouraged because of the theoretical risk of transmission of slow viruses, such as Creutzfeld-Jakob disease. 2 Cartilage. This is also available locally and biocompatible. However, it has a tendency to lose its rigidity over time and is difficult to shape. 3 Plastics. Teflon and polythene tubing were introduced originally in the 1960s but have been superseded because of their high rejection rate. 4 Biocompatible synthetics. Plastipore is a high-density porous ethylene, available in a variety of preformed shapes. It also has a tendency to extrude, although this can be delayed by interposingcartilage between the device and the tympanic membrane (TM). 5 Bioactive glass (e.g. Ceravital and Bioglass) was introduced in the mid-1980s. It promotes soft-tissue attachment, does not need to be covered with cartilage and promotes an osteogenic reaction. However, it is quite brittle and therefore difficult to trim to size. 6 Bioceramics are currently popular, especially hydroxylapatite and its derivatives. This is designed to resemble the mineral matrix of human bone and the dense form can become mineralised by calcium to become incorporatedas vascular bone. Extrusion may occur if it is incontactwiththeTM,andcartilage reinforcement is wise in such cases. ’7 Glass ionomer cement. This has recently been introduced ina variety of forms, including preformed

This is one of the commonest discontinuities. The appropriate and time-proved technique is incus transposition (Fig. 10.2). The only disadvantageof removing the body of the patient’s own incus is the slight loss of support to the posterior part of the attic region. This is not usually a significant factor unless repairing a defect of the posterior part of the pars tensa. The alternative is a hydroxylapatite partialossicular replacement prosthesis (PORP).The author finds the notched Wehr’s device easiest to insert (Fig. 10.3). The GrotePORP is designed to lie in a pocket between the handle of the malleus and the TM, but it can be difficult to achieve the necessary pocket and insert the straight limb of the prosthesis. Absent suprastructure of stapes

Selection of a device depends on whetherthere

is

Groove here for malleus handle

j

stapes head

I

Fig. 10.2 Modification of eroded incus for transposition. Use a fine diamond-paste burr.

54

Chapter 10

Fig. 10.3 Hydroxylapatite partial ossicular

I L

a malleus handle to actas an anchor; in this case use anotched TORP such astheWehrs (Fig. 10.4). When there is no malleus handle, direct contact with the membrane calls for a reasonable surface area of TORPto collect thesound energy. In addition, a degree of tension is required to promote the equivalent of thecatenary(chain-like) effect of the middle ear transformer mechanism. Unfortunately, the cases where thereareno useful ossicles to build onare oftenpost-canal-wall-down mastoidectomies; when the bridge has been taken down and the facial recess opened at the original surgery, the distance of the tympanic segment to the footplate is reduced. This loss of height makes adequate TORP placement more difficult. Lenticular process only absent

This is a minor variant of eroded long process of incus. It is often the most satisfying to reconstruct in a variety of ways.

I replacement prosthesis.

Procedure

1 Perform tympanotomy.

2 Evaluate the problem and measure the distances. A stapedectomy-type measuring rod is useful; crocodile forceps can be used to estimate horizontal gaps against a sterile ruler. Successful reconstruction requires tension in the middle ear.A distance of more than2.5mm between the stapes and malleus is associated with poor results. 3 Check the mobility of the stapes. It is easy to overlook a small degree of tympanosclerosis. NB If the stapes suprastructure is damaged or absent, the results are significantly worse. 4 Decide on the material to be used (see section above on biomaterials).A familiarity withthe designs and availability of a large number of devices is essential in the operating room. 5 DrilUtrim prosthesis to size. Always trim less than you think is necessary and then ‘try’ it in place before making final adjustments.

Ossiculoplasty 6 Place in position. NB Do not push on to the head of the stapes or on to thefootplate directly while trying to place a device under the malleus. Instead, always lift the malleus with a needle or hook. At this stage, two-pronged a micromanipulator (e.g. Cawthorne, Austin)is very helpful to move the bonelimplant and to hold it in position with one hand while lifting the malleus with an angled pick. A selection of alligator forceps pointing sideways and upwards can be helpful to position the device initially without obscuring the surgeon’s view. In the case of a narrow oval window niche, the bony overhangs make ankylosis more likely.

Theear is closed in the usual way withsubcuticular absorbable skin sutures.

The patient may experience dizziness for 1-2 days but is usually well enough to go home within 24 h.

55

1 Injudicious manipulation of theovalwindowarea may lead to sensorineural deafness. 2 Facial palsy is a rare complication. 3 The prosthesis may extrude between 6 and 24 months postoperatively. 4 Persistent conductive deafness should be re-explored.

Briggs RJS & Luxford WM (1994) Chronic ear surgery: a historical review. Am J . Otol. 15 (4), 558-67. Browning G (1993)Reporting the benefits of middle ear surgery. Am. J. Otol. 14, 135-40. Monsell EM (1994) Ossiculoplasty. Otolaryngol. Clin. North Am. 27 (4). Toner JG, Smyth CD & Kerr AG (1991) Realities in ossiculoplasty. J . Laryngol. Otol. 105, 529-33.

Stapedectomy TONY WRIGHT

lndications

Reduced bone-conduction levels

Absolute

The worse the bone-conduction level, the less likely a good result as far as the patientis concerned. If the airbone gap is closed, butthere is still the need fora hearing-aid, then very little has been achieved at some risk. The patient’s aim is to throwaway the hearing-aid, not to swap it for a less powerful model.

There are no absolute indications since otosclerosis can always be managed by some form of hearing-aid. Relative indications

1 A bilateral conductive loss caused by otosclerosis, ratherthan tympanosclerosis, withnormaltympanic membranes (TMs)and withnormal or near-normal bone conduction (after making allowance for the Carhart effect) is the best indication. 2 Unilateral otosclerosis. The author is not certain that this is the same pathology as bilateral otosclerosis although he has no evidence to support this statement. However,the author will operate following a 3-6month period of regular use of a hearing-aid on the affected side. This is because the sudden reintroduction of sound following a successful procedure can be extremely distressing withthesounds being unbearably loud for many months. One must be absolutely certain of the audiometry and be positive that one is not operating on a progressive unilateral sensorineural hearing loss.

Relative contraindications

Tympanosclerosis

A fixed footplate from previous middle ear disease is not, for the author,an indication for stapedectomysince the outcome is very much less certain, although he is not sure why.

Age

Age is no contraindication and the younger patient with Van der Hoeve’s syndrome need not delay operation. The wisdom of performing stapedectomies on the elderly is questionable since the slight loss of discrimination that inevitably comes from a stapedectomy may be enough to make an elderly person worse off despite an improved threshold. Contraindications

1 Active external or middle ear disease forbids surgery. Unless the ear canaland the T M are perfect or nearly so, the author will not offer the procedure. 2 Tinnitus is notan indicationfor surgery. Tinnitus may improve or even resolve following a successful stapedectomy, but this cannot be predicted and should be considered a bonus. Tinnituscan easily be made worse. The single, specific aim of the operation is to improve the hearing by closing the air-bone gap. Summary

Because theprocedurecan go disastrously wrong, individual patients almost have to ‘demand’ an opera-

Stapedectomy tion, rather than have it forced upon them by an eager surgeon. The patient with a dead ear, tinnitus or vertigo after afailed stapedectomy is with you for ever. Remember the late Gordon Smyth’s words: ‘There may be many moredeadearsfrom surgery thanfrom middle ear disease’ (Smyth, 1980). Thus,stapedectomy surgery should be undertaken by individuals who regularly performtheprocedure and there is almost certainly no place for the ‘occasional stapedectomist’. The person who performs stapedectomies in the ‘centre’ should be actively involved in teaching those trainees who are at a senior level and who want to continue in otology. If a registrar were performingastapedectomyunderthe guidance of a senior registrar and somethingshould go wrong,the case would be difficult to defend. Thetechnique of small-fenestra stapedectomy has been essentially unaltered for 20 years. However, the technology has changed and microdrills and lasers are now available, but then so are better microscopes and video recordings of theprocedure. What should be available and what is a necessity? Legally the argument that ‘the available financial resources were insufficient’ is used to defend thenonavailability of services or items of equipment.In addition, a ‘responsible body of medical practitioners’ perform stapedectomies without microdrills or lasers with good results, and this argument, based on the socalled Bolam principle, is, at present, enough to justify the non-essential nature of their use. However,both microdrills and lasers are very useful additions to the surgical instrumentation and will in due course become something that no otologist can be without. The individual should, however, practise on temporal bones in theatreprior to surgical use. As to other items, it is absolutely essential to have the appropriate fine instruments for working in the region of the footplate and one should not consider startingstapes surgery without them.

Preoperative management History

It is important to establish what the individual patients hope to achieve from the procedure and why they want an operation so that their expectations and reality can be matched. Examination

The ear canal should be free of active otitis externa and

57

not narrowed by exostoses or osteomata. These need removal prior to considering a stapedectomy. The T M should be normal and,if the surgeonis certain that there is a positive Schwartz’s sign (a definite pinkish red glow from the promontory), then it is probably better not to operate until the progression of conductive loss has ceased, since the results seem to be less good with more sensorineural losses occurring. investigations

Really goodaudiometrywith reliable masked boneconduction levels is an absolute necessity. Do not even consider operating unless you are sure of the audiogram. The difficulty comes in a patient with a major conductive loss in one ear and, by chance, a predominantly sensorineural loss in the other. This is a most awkward combination to test because of masking difficulties. Tympanometrywith ipsi- andcontralateralstapedial reflexes might be helpful in earswitha recruiting cochlear-type loss. Retrocochlear losses may be detectable if stapedial reflex decay can be shown. Tuning-fork tests are sometimes very helpful and the author likes to have a preoperative Weber test result so that postoperative changes can be detected. If available, speech audiometry should be performed to assess theoptimumdiscrimination score. If this is low, say less than ’70% in the ear for surgery, then the chance of a good result as far as the patientis concerned is also low. Warning of risks As well as explaining theoperation

in the degree of detail that the patient wants, it is necessary to explain the risks in clear terms and to write in the notes and in the letter to the referring doctor thatyou have warned thepatient of them (Morrison, 1989). It is better to writedown what risks you have described since patients’ memories are fickle (Hutson & Blaha, 1991). Those risks are: 1 dead ear; 2 vertigo; 3 tinnitus; 4 alteration in taste to the side of the tongue; 5 that the operation might not work and that the conductive loss might persist; 6 a small risk of a facial palsy and therefore a facial weakness. Thereported incidence of sensorineural hearing loss varies from 0.5% to 4% in skilled hands (Beales, 1987), but the author can find no good figures for the other

58

Chapter 11

outcomes, although he continues to see patients with such complications. The author does warn patients of the small risk of a facial palsy, since it certainly has occurred and they need to be positive that they really do wantsurgery. If, having heard the risks, they do not want to go ahead, then nothing is lost because the conditionitself is not dangerous and is well managed by hearing-aids. If they do go ahead and a risk materialises, then the case is easier to defend, at least as far as consent is concerned.

The author has only occasionally performed stapedectomies under local anaesthesia because of the excellent hypotensive anaesthetic service providedfor him over the last 10 years. However, for a stapedectomy under local anaesthetic (LA), sedation with Omnopon and scopolamine is advised. Local anaesthetic technique

About 1h before the operation the author fills the ear canalwithaeutecticmixture of localanaesthetic (EMLA) cream, ensuring that the cream is lying on the TM.In the operating theatre xylocaine 2% with adrenaline l :80 000 is injected through multiple sites in the postauricular sulcus with the tipof the needle pointed to the meatus and with a separate injection in the groove between, the tragus and the superior rim of the helix. Then, using a Tumarkin slotted speculum and suction, the EMLA cream is aspirated andLA is injected into the skin of the meatus. The idea is to strip the skin and periosteum from the underlying bone in muchthe same way that an injection isused in submucous resection (SMR) of the nasal septum. The trick is to use a large speculum and inject at thejunction of thebony and cartilaginous canals in a slowish fashionso that skin in the deeper canal blanches but does not blister. Under general anaesthesia the author also injects the ear canal to make raising the tympanomeatal flap less bloody. General anaesthetic technique

Hypotensive anaesthetic with systolic pressures stablised at around 70-80mmHg and with a head-up position makes for a relatively bloodless field.

Theauthor doesnot give prophylacticantibiotics. If there is any suggestion of active infection, a stapedectomy must not be performed, siti

The patient lies on hislher back with the headon a head ring so that it can be turned away from the side of the operation.

Endaural incision

The author makes a small endaural incision in all cases and then takes two or three large pinhead-sized pieces of subcutaneous fat from this incision and saves them in saline. If general anaesthesia isbeing used, the tragal notch is not injected with local anaesthesia. The author then cuts down through this incision in order to open the meatus and two-tined Plester self-retaining retractors are used. Occasionally, and irritatingly, the inferior portion of the helix and ear lobe pivots into the line of view when the Plester retractors are opened and there may be a need for a stitch through the lobe or another Plester retractor, this time with a flat blade to improve the view. If the patient has a pierced ear lobe, then a thick silk suture can be passed through this and used to provide traction. The tyrnpanorneatal incision

The authoruses a round canal knife to make an incision parallel to the annulus and about 3-4mm from it, extending from 6 o’clock to 11 o’clock (Fig. 11.1).This cut is down to bone andshould barely bleed if the injection has been performed correctly. Then, with the help of a small cotton-wool ball soaked in adrenaline solution,the cuffof canalskin is elevated, using a Beale’s elevator. Do not suck on the canal skin for this is fragile, precious stuff. Small scissors often have to be used to cut the thicker skin over the outer attic wall. The middle ear is entered mosteasily inferiorly, using a small Beale’s elevatoror,better,aHugh’sraspatory to get between the sulcus and the annulus itself. Theannulus is then elevated andthe TM turned forwards, the chorda tympani being dissected from the TM in the process, until the flap is hinged on the handle of the malleus (Fig. 112 ) .

Stapedectorny

59

Check the diagnosis

Fig. 11.1 A tympanomeatal incision has been made with a round canal knife and a Beale’s elevator is being used to lift up a cuff of canal skin.

Using a slightly curved needle, the malleus handle is gently rocked by pushing against the medial aspect of it in a medial to lateral direction, to see that there is full and free movement of the tip of the long process of the incus. If there is fixation of the heads of the ossicles in the attic, then, afterchecking the mobility of the stapes, the author closes the ear, since to proceed with a nonconsented operation is not acceptable in non-lifethreatening conditions. To check the mobility of the stapes you must be able to see it and this is not always possible because of a prominentposterior bony canal wall. This needs removal and the author uses House curettes (large and small) asthese are particularly sharp butdo need replacing at regular intervals as they wear out. A curetteis not used like a lever, but rather like an ice-cream scoop with the sharp edge shaving away layers of bone. The difficulty arises around the entry of the chorda tympani into the bony canal wall and greatcare, using the small curette, is needed to release the nerve from its canal without damage. Enough bone should be removed so that the stapedius tendon and pyramid canbe seen. This fairly extensive removal of bone also allows in more light, which is a greathelp when looking at the footplate (Fig. 11.3). The stapes’ mobility is then checked by using a small Hugh’s raspatoryto try and rockthestapesin an anteroposteriordirection. If it is immobile, thenthe diagnosis is confirmed. Dividing the incudostapedial joint

Fig. 11.2 The tympanomeatal flap has been lifted and turned anteriorly until it is hinged on the handle of the malleus. The chorda tympani runs across the long process of the incus and partly obscures the view. The dotted lines on the posterior bony canal wall indicate the region of bone that should be curetted in order to improve access and lighting. The facial nerve (VII)lies just above the stapes and it is sensible to gently palpate this with a blunt instrument to ensure that the bony covering is intact.

Assuming that there are no major anatomical difficulties andthat thefootplate is not completely obliterated (these will be discussed briefly later), the incudostapedial joint is then divided. The neatest instrument is a small roundjoint knife and this is rotated throughthejointawayfromthestapediustendon, which is used as countertraction (Fig. 11.4). The author then cuts the stapedius tendon with small microscissors close to theneck of the stapes (Fig. 11.Sa). Itis no longer necessary to make a preliminary hole in the footplate, since the incidence of ‘perilymph gushers’ is so low and it is much easier to control any bleeding around the footplate region with it intact.

60

Chapter l 1 in saline, around the incudostapedial joint and tries to get the cutend of the stapedius tendonto stick to the fat. The ear is then closed. This operation is then equivalent to a Rosen’s stapes mobilisation, which often gives good hearing for some months or years until the fractured otosclerotic focus heals. If the patient then wants further surgery, theargon laser can be used to ‘fragilise’ the crura. Use of the laser

Fig. 11.3 After curetting the bony canal wall, the tip of the pyramid is visible and the chorda tympani can be gently elevated out of its canal and deflected inferiorly.

The author is increasingly using the argon laser during stapedectomy. The angled middle ear GheriniKaufmann endoprobe has an extremely fragile tip and must be used with great care. To ‘fragilise’ the posterior crus 0.2 S bursts are used at a power setting of 2W. The tip of the probe is placed lightly on the posterior crus and the laser fired. This is repeated, moving the tip a little sideways until the black carbon line is seen across the posterior crus. Unless there is a direct view of the anterior crus, the author does not use the laser blind because of the risk of damaging the facial nerve. With

Fig. 11.4 A small joint knife is being used to cut through the incudostapedial joint. It is gently inserted between the lenticular process of the incus and the head of the stapes and rotated from side to side. The angle of the blade on the shaft makes this a relatively simple manoeuvre.

Fracturing the crura

The author uses a slightly curved needle and, with this between the facial nerve and thearch of thestapes, gentle pressure is exerted against the arch of the stapes in an inferior direction (Fig. 11.Sb).While doing this, it is very important to keep the microscope focused on the footplate and to look at the footplate. If this starts to mobilise while trying to fracture the crura, the author stops the operation, wraps the fat, which has been kept

Fig. 11.5 (a)Some microscissors are used to cut the stapedius tendon close to the neck of the stapes. (b) With the tendon cut, a small curved needle or hook can be used to deflect the crura inferiorly away from the line of the facial nerve.

Stapedectomy

6I

felt and then it is time to move up to the larger 0.8 mm trephine (Fig. 11.7’). This is used untilthe increased torque is felt again and is then stopped. Theauthor does not use a microdrillto perforate the footplate, but this is an alternative way of creating a smooth 0.8 mm diameter stapedotomy. Once the stapedotomy has been created, suction must never be used near the oval window niche. If perilymph obscures the view, it may be absorbed using very small, dry, cotton-wool pledgets. Inserting the piston

Fig. 11.6 When using the trephine to penetrate the footplate it is important to have good control over the movement. This is achieved by having the shaft of the trephine resting on the index and middle figures of the left-hand (for a right-handed surgeon) and gently rotating the shaft using the index figure of the right-hand. Using the index figure of the left-hand is a good technique for stabilising the instruments down the ear canal and this technique can also be used during placing the piston and crimping the platinum band.

the posterior cruseffectively broken, then fracturing the anterior crus is ver
With the cruraremoved, the footplate is visible. There is often a thin mucosal membrane over this, which needs to be removed and which then bleeds. Suction can be used to clear the blood as the footplate is intact. The laser can be used at its lowest power setting of 1W for 0.1 S bursts as ‘diathermy’ to the small vessels running across the footplate. If a laser is not available, a pledget of adrenaline-soaked cotton wool canbe left in the oval window niche until any bleeding hasstopped. If the laser is set up, one or two0.1 S bursts at a power setting of 2 W in the centreof the footplate are used to make a small starting-point for the stapedotomy. The author uses ahand-heldtrephine to makethe hole, startingwitha0.6mm Fisch trephine.This is allowed to rest on the footplate with the pointed tip in the laser burn if one has been made. The shaft of the trephine is rotated back and forth using the thumb and middle finger of the right hand (Fig. 11.6). It is sometimes helpful to rest the shaft of the trephine on the extended index finger of the left hand in order to reduce any tremor. No downward pressure is applied to the trephine, the weight of it being enough. When the trephine is just through the footplate, there is a sudden increase in the torqueof the rotating shaft. Thisis easily

The author uses a Teflon-platinum piston with a shaft diameter of 0.5mm. The platinum band is easy to hold and crimps beautifully. The loop needs to be opened very slightly to get it over the average-sized incus and the piston is held in fine crocodile forceps in the right hand. The piston is then guided into the ear, resting the shaft of the crocodiles on the index: finger of the left hand. The tip of the piston is put into the stapedotomy first and the loop of the prosthesis is slid over the incus and gently pushed down to ensure that the tip of the piston is definitely within the stapedotomy (Fig. 11.8). The authoruses a 4.0 or 4.25mm piston for virtually all ears and no longer measures the distance between the footplate and incus. Crimping the platinum band

This is also a very difficult manoeuvre and needs good fine crimpers to work nicely. The author starts to close the loop with fine crocodiles, again held intheright

Fig. 11.7 The smaller O.6mm trephine is used to create a small central perforation of the footplate. After rotating the trephine until an increased resistance is felt, the larger 0.8mm trephine is used to enlarge the pilot hole. This gives a precise, ‘punched out’ hole and is a quick simple technique. The microdrill using a combination of diamond paste burrs and the perforator can be used to a similar effect.

Fig. 11.8 (a) The platinurn band of the platinum and teflon prosthesis is gripped by crocodile forceps and the tip of the piston is inserted into the stapedotomy. (b) The wire is then manoeuvred over the long process of the incus and then crimped gently so that there is a firm, but not tight, fit and the continuity checked by gently moving the malleus handle in the same way that the diagnosis was checked initially.

hand and resting on the index finger of the left. Once theplatinum has started to close, fineFisch-McGee crimpersare used to complete the job. The malleus handle is then gently moved to check that there is no excess ‘play’at the new incudoprosthetic joint, although very slight movement is needed.

the canal, and a few small pieces of bismuth, iodoform and paraffin paste (BIPP)ribbon gauze are laid on topof them. If there has been extensive curetting of the posterior canal wall, the tympanomeatal flap may be a little short. If this happens, the endauralincision can be deepened and a small piece of temporalis fascia taken as an underlaygraft.Theintactcanal skin will have to be rolled laterally and this may require one or even two longitudinal incisions so that the fascia can be laid on the bony canal wall to cover the defect and then itself be covered with canal skin and the tympanomeatal flap. Thewound incision is closed withsubcutaneous 4/0 Vicryl. A small 2 cm X 1cm strip of Silastic is then rolled up like a Swiss roll along its long axis, held in crocodile forceps, placed in the ear canal and allowed to unroll. This small tube of Silastic is then filled with a few more pieces ofBIPP ribbon gauze. A piece of cotton wool completes the dressing to the ear canal and a square of Melolin is used to cover the endaural incision. The author uses packing in the ear canalbecause there is oftensome bleeding fromtheendaural incision. A plug of driedbloodstuck to the T M is particularly difficult and uncomfortable to remove and makes early assessment of the success of the procedure very difficult. The author thinks it is irrelevant what sort of packing material is used so long as it is not pushed into the ear canal with therisk of displacing the tympanomeatal flap into the middle ear. Check the patient’s facial nerve function in the recovery area and note this in the operative record.

There is no need to restrict mobility and patients can be up and about as soon as they recover from the general

Sealing the stapedotomy

Tiny fragments of fat are cut from the stored pieces on a glass slide, using a new scalpel blade, and are picked up onthe tipof a straightor slightly curved needle. They are then carried into the ear and placed all around the site of entry of the piston into the stapedotomy (Fig. 11.9).

The T M is then replaced. In all cases the author then uses small 1cm X 3 mm strips of thin Silastic sheeting (0.05mm) to lay over the line of the tympanomeatal incision. These strips are laid with their long axes down

Fig. 11.9 Some small pieces of fat taken from the endaural incision are placed around the base of the piston to ensure that perilymph leakage is minimal, thereby reducing the risk of postoperative vertigo or of a labyrinthitis. Very small pieces of fat can be used and give a cosmetically pleasing result.

Stapedectomy anaesthetic (GA). Check for the presence of nystagmus and facial weakness, perform a Weber testand write the results in thenotes. Assuming all has gone well the patient canleave hospital next dayand have the packing removed after a week. The author does not allow patients to fly for 2 weeks postoperatively, although there are no data on which to base this decision. After a successful stapedectomy on theworse-hearing ear, many patients ask whenthey can have an operation on the other side. Provided there are no other contraindications and the first ear has given no trouble whatsoever, the author is happy to perform the second-side surgeryaftera6-month delay. The hearingimprovement is rarely so dramatic and this should be carefully explained, since the risks are just the same -not less.

Common complications intraoperative

Obliterated footplate

If the oval window niche is completely filled with bone, or if the footplate is so thick over all its extent that itis difficult to distinguish fromthesurroundinglabyrinthine bone, the author stops the operation. The risk of causing a sensorineural loss in drilling out a thick footplate is not justified when improvements in hearing-aid technology have madeit relatively easy to help most conductive losses. Low facial nerve, high promontory Sometimes the oval window niche is very narrow. The bony promontory overhang can be carefully drilled back to improve exposure, but unless there is a good view of the footplate the author abandons the procedure. The footplate cracks during the stapedotomy

Occasionally the footplate cracks across its width when the stapedotomy is being created and the posterior portion of the footplate floats. If the stapedotomy hasbeen created, then a very small hook can be inserted through thestapedotomyandrotatedsothatthehook faces posteriorly and the fragment whichis hinged posteriorly can be elevated out of theovalwindow. Somefine crocodilescanthen be used to extractit. If the stapedotomy has not been created, then the small curette can be used to enlarge the oval window immediately posterior to the footplate and the same small hook then inserted through the annular ligament underneath

63

the posterior margin of the footplate; the footplate can then be rotated backwards, using a Hugh’s raspatory to tilt the footplate with the angled hook as the fulcrum. Once the posterior halfof the footplate has been removed, the piston is inserted and sealed as described above. Never use suction in the oval windowregion with the footplate open. Postoperative

Vertigo

With the piston in place and the stapedotomy sealed, vertigo isvery uncommon, and if itdoesoccurthen usually settles rapidly. Persisting vertigo is very worrying. The patient shouldbe kept in hospital. In the notes, recordthe severity of the vertigo, the presence and degree of any nystagmus and the lateralisation of the Weber test and have bone conduction audiometry performed on a daily basis. Provided the bone-conduction levelis maintained, then the patient can be managed conservatively. If there is a dead ear and persisting vertigo, then it is worthwhile re-exploring the ear to check that the piston is in place and that the stapedotomy is sealed. If there is a slowly progressing sensorineural loss with persisting vertigo, thenthe possibilities area perilymph leak or a reparative ‘granuloma’ of the footplate. These granulomas seem to be very rarewith small-fenestra stapedotornies and so the ear should be re-explored to exclude aperilymphleak. The author gives a detailedand explicit explanation to the patientof what is thought to be happening, of the risks of leaving thingsalone and of operating(whicharehigh),and makes detailed notes. If consent is given, then the seal around the footplate should be checked and replaced if necessary. In the unlikely event that there is a proper granuloma, as muchof this is removed as possible without removing the piston, and a short course of high-dose oral steroids and antibiotics is given.

Alternative procedu There are almost as manydifferent ways of performing astapedectomyastherearesurgeons who perform them, and some intriguing manoeuvres havebeen described. There is no correct way of operating, but certainly some mistakes to avoid. Treat the tissues gently and neveruse suction on or near the open footplate. Youneed the correct instruments for a stapedectomy and it is definitely not worth contemplating the procedure unless you have a full set.

References Beales PH (1987) In: Scott Brown’s Otolaryngology, Vol. 3, Otology. London, Butterworths, p. 335. Hutson MMcD & Blaha JD (1991) Patient’srecall of preoperative instruction forinformedconsentforanoperation. J. Bone Joint Surg. 73, 160-2.

Morrison ATV (1989) Twenty one years of otolaryngology litigation. J. Med. Defence Union Spring, 4. Smyth GDL(1980) Chronic Ear Diseuse. Edinburgh, Churchill Livingstone, p. 49.

Mastoid Surgery JOHN P. BIRCHALL

Indications Cholesteatoma is the primary indication, with being the only treatment option.

Chronic suppurative otitis media

surgery

ontraindications The only absolute contraindication is where the risk of surgery outweighs therisk of potential serious complications. Severe cardiovascular or respiratory disease are the major contraindications;age per se is not. Operating on the only hearing ear is a relative contraindication, when each case must be taken on its merits. However, this is not territory that should be occupied by the inexperienced, nor are cases with concomitant congenital ear malformations.

Preoperative management History

Cholesteatoma due to the accumulation of keratin debris in the sac provides an ideal environmentfor anaerobic bacteria; mucopus is’formed and, if profuse, then discharge is noted by the patient. If less profuse, the discharge may dry within the external auditory meatus (EAM), forming crustswhich then obscure the mouthof the sac and mask the diagnosis. An unobstructed view of the EAM and tympanicmembrane (TM) is therefore mandatory. This may be possible with microscopic aural toilet in the clinic, or may require a general anaesthetic (GA), but must be performed adequately in any patient with ahistory of intermittent foul-smelling aural discharge. The differential diagnoses include foreign body, otitis externa and chronic suppurative otitis media (CSOM) without cholesteatoma.

CSOM classically presents with intermittent aural discharge, which is often mucoid and does not have an offensive smell. Most cases will, for a short while, settle withtopicalantibiotics.Oncetheear has settled it should be inspected; the majority of cases will be found to have a chronic perforation throughwhich the middle ear mucosa is visible. Cases that have had years of discharge or significant conductive hearing loss should be considered for surgery. Chronic stable perforations in the presence of normal middle ear mucosa should be offered a simple myringoplasty. If the middle ear mucosa is hypertrophic, a CT scan or MRI scan should be performedand if thisshows thickened mucosa thena combined-approach tympanoplasty should be offered. Chronic discharge coming from the middle ear is due either to a cholesteatoma or to CSOM. Both can give rise to cerebral complications so neither is ‘safe’.

Relevant anatomy External ear

This description is presented in the order that it would be encountered surgically via an endaural approach. 1 The anterosuperior extent of the pinna extends anterior to the skin incision and therefore could be cut if the incision is simply deepened. 2 Thetemporalis fascia and muscle lie deep to the preauricular muscle and vein. 3 The cartilaginous outer third of the EAM is covered with skin containing ceruminous glands and hairs. 4 The spine of Henle lying posterosuperiorly in the bony EAM has irregular contours and varies in size,

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Chapter 1,2

Mastoid process

/

5 The facial nerve turns through 90" to leave the middle ear just abovethepyramid and slightly lateral to it, forming its third (mastoid, descending) part. The anterior part of the lateral semicircular canal is in very close proximity to the facial canal posteriorly. This area corresponds to where the deep extension of aposterior tympanotomy cut is made in combined-approach tympanoplasty. 6 The ligament of the short process of the incus is quite strong and the malleolar-incudeal joint is tight; therefore the incudostapedial joint should be divided before the incus is removed to avoid excessive mechanical energy reaching the inner ear. 7 The handle of the malleus is firmly attached to the fibrous part of the TM; the tensor tympani tendon is strong and therefore the malleus head should be cut off just above the lateralprocess of the malleus. The head of the malleus is held by the superior and lateral malleolar ligaments and can now be avulsed.

Fig. 12.1 Lateral surface of the right temporal bone.

Clinical assessment prior to definitive surgery (cholesteatoma) resulting in firm tethering of the overlying skin.The squamomastoid suture running longitudinally along the floor of the EAM is also responsible for firm tethering of the overlying skin (Fig. 12.l). Middle ear

1 The body of the incus lies in close proximity to the medial end of the posterior meatal wall and is at risk of being damaged as bone is removed. This is important if the incudostapedial joint is intact, for vibrations will be transmitted to theinnerearwiththe risk of sensorineural hearing loss. 2 The incus with its short process attached to the incudal fossa is a good landmark for the lateral semicircular canal, and its long process to the stapes straddles the facial canal, which lies deep to it, and is thus the most useful landmark in identifying the course of the facial nerve. 3 The stapes, with its stapedius tendonarising from the pyramid, lies immediately anterior to the distal portion of the second (tympanic, horizontal) part of the facial nerve, the proximity being such that a dehiscent facial canal in this area may prevent the safe placing of a stapes prosthesis. 4 The facial canal bulges convexly anteriorly and thus hasa small concavity medial to it,the facial recess. Between the laterally lying pyramid and the medially lying facial recess lies the sinus tympani.

The Rinne and Weber tests should always be performed to detect adeadear, which could be missed by an inexperienced audiologist. 1 There is often a conductive deafness, which may be suggested by tuning-fork tests. An air-bone gap of 4050dB indicates an ossicular discontinuity, usually the loss of the long process of the incus. 2 The fistula test should be performed, particularly if there is a history of vertigo, although it can be negative where a labyrinthine fistula is present. If positive, it may change the managementin that a senior surgeon may do the case. 3 If cholesteatoma is the presumptive diagnosis, radiology is not necessary, except in children or if a concomitant congenital ear malformation is present. Much was made in older texts about radical erosion of the scutum, but an erosion of the outer atticwall should be obvious at otoscopy or microscopy, and X-ray imaging is pointless. If the diagnosis of cholesteatoma is definite, the patient should be listed for an exploration of the affected ear, andonly at the time of surgery will the extent of surgery be determined. 4 If there is doubt about the diagnosis after examinationunderthe microscope in out-patients,then give acourse of gentamicin ear-drops- three drops t.d.s. until reviewed in out-patients in 2 weeks' time. If on review the diagnosis is still in doubt, list the patient for an examinationunder general anaesthetic (EUA).A small localised cholesteatoma may onlyrequire an

Mastoid Surgery atticotomy; a moreextensive one would require a modified radical mastoidectomy, and very rarely a radical mastoidectomy is needed if disease proves to be extensive, involving the anterior part of the middle ear cleft. 5 Many trainee surgeons are confused by the surgical a where terminology. An atticotomy is procedure bone is removed from the outer atticwall, just sufficient to remove the cholesteatoma, the defect being grafted with temporalis fascia, or chonchal cartilage for larger defects. When healed, the TM and EAM will appear normal or nearly normal. In a modified radical mastoidectomy themastoid is exteriorised, the facial ridge is takendown and the incus and the head of the malleus are removed, but the stapes superstructureis usually left intact.Thehandle of the malleus and the T M anterior to it are left to allow closure of the middle ear with temporalis a graft. A radical mastoidectomy would involve the sacrifice of the handle of the malleus and TMremnant, with the disadvantage that fashioning of an air-containing middle ear is difficult or impossible. The main advantage of leaving an air-containing middle ear is that the secretions of the middle earare prevented from reaching the EAM, avoiding aural discharge, particularly with upper respiratory tract infections (URTIs). Perforations are marginalor central, and although the former are usually associated with cholesteatoma they can be found in CSOM. Furthermore, central perforations and even no perforation (at the time of examination) may, be found with cholesteatomas. In children with persistent foul-smelling intermittent discharge, irrespective of the otoscopic findings, and even at EUA where no sac or perforation is found,cholesteatoma should still be suspected andatympanomeatal flap raised to inspect the middle ear. Each case has to be taken on its merits, but it would be prudent to discuss the case with colleagues and note that it may be worth referring to a more experienced otologist to explore the ear.

Examination under anaesthetic Aural polyps may protrude into the EAM. These are attached to underlying structures, usually bone, but may be in contact with thefacial nerve if the bony canalwall is dehiscent and thereforeshouldnot be forcefully avulsed. A cutting snare shouldbe used to amputate the body of a polyp at the base. Apply a cotton-wool ball soaked in 1:1000 adrenaline solution (but do notposition with a sucker, which then aspirates all the adrenaline solution!). Wait at least 3min timed by the theatre

67

clock. Gently roll the ball off the base of the polyp, and if haemorrhage is controlled then the origin and anatomical relationship of the polyp to the facial nerve may be determined. If it is not possible to control the bleeding, apply a bismuth, iodoform and paraffin paste (BIPP) pack and remove in the out-patient department in 2 weeks when the ear,in the absence of haemorrhage, can be better assessed.

Preoperative explanation and informed consent In the clinic, the patient should be told that he/she has a cholesteatoma, ‘which is a bag of skin that is growing into the middle ear’, and that‘it is not malignant’. If left untreated,it may result in deafness, dizziness, facial palsy and in some cases brain abscess and death. The onlytreatment is surgery andit is ‘quite acommon condition requiring a mastoidectomy’. The purpose of the operationis to remove all the cholesteatomato leave a safe dry ear and not toimprove hearing. Hearing may be worse after the operation and rarely total deafness may result. Tinnitus may arise or be made worse. Loss of taste on the side of the operation may be experienced in the mouth or on the side of the tongue, or taste may seem different. The consequences of damage to the facial nerve should be made explicit, that is, that side of the face will be completely paralysed and this may be permanent. The reason forsurgery and thepossible complications should be repeated on admission. All juniors must warn about facial palsy and whatthe consequences are to the patient. Medicolegal difficulties could arise if a junior surgeon is invited to perform the operation when the patient is being or has been anaesthetised, if the patient has not been warned about the possibility of facial-nerve palsy. It is better for the consultantto have a policy that does not allow such circumstances to arise, the best being to let the junior surgeon knowexactly what he/she is doing on the list before the patients have had their anaesthetic premedication. Describe the site of the incision and explain that you may have to remove some hair and thatwhen they wake up they will have a head bandage onand will feel nauseated and possibly vertiginous. All being well, they will be discharged the day after surgery and will be seen in out-patients 2 weeks later to have the pack removed. Should they in the intervening time develop increased deafness, tinnitus, vertigo, discharge or pain or problems with facial movement then they should immediately return to the unit and not totheir GP. Finally, the patient should be invited to ask questions.

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Chapter 12

Mastoid surgery can be performed in adults underlocal anaesthetic (LA), butthis is much more time-consuming and unpleasant for the patient and should only be considered where surgery is essential and a CA is a risk to life. Themostimportantpart of theanaesthetic is a smooth induction, as it seems to be the only common factor in obtaining relatively bloodless surgery.

A GA is given via

an endotracheal tube (ET) with the patient lying supine with the head turned away from the surgeon, the earto be operated on being uppermost. The table should be tilted head-up and the head firmly supported but not fixed, using a head ring. This will allow the surgeon to move the head while operating, which makes for better visualisation and increases the speed of surgery.

Starting on theday of surgery a3-daycourse of Augmentin, trimethoprim or azithromycin should be prescribed.

keloid formation, but theincision is a matterof personal taste. 2 Prepare the skin with a mediwipe, infiltrate with 2% lignocaine and 1:80000 adrenaline from a dental syringe prior to scrubbing up. Inject deeply down to the bone and, while withdrawing the needle, inject 4-6ml. The injections should be at the site of theendaural incision or postaural incision, and deep enough to infiltrate down to themastoid bone and beneath the skin of the EAM. (The latter is easier to do after scrubbing up, when the microscope is available. Try to lift the skin with the injection by ensuring the needle tip is in close proximity to the bone of the posterior wall of the EAM and the needle’s bevel is facing bone, not skin.) While scrubbing up, the scrub nurse should prepare the operative field with aqueous betadine and towel up. 3 Shaving is usually not necessary, but if the patient’s hairstyle leaves ‘uncontrollable hairs’ shave or trim after injecting. Always inspect the ear under the microscope before making the skin incision, thus reducing the risk of operating on the wrong ear. 4 Anterior to the helix make an incision with a number 10 blade through the skin following the curve of the helix (Fig. 12.2) for about 1.Ocm from the inside of the EAM at the 12 o’clock position. Extend the skinincision into the EAM to the bony portion and then make a circumferential incision parallel to the annulus fromjust anterior to the first incision to the lowermost point on the floor of the EAM.

The aims of the procedure are to find the mouth of the cholesteatoma sac, to dissect the cholesteatoma sac out in toto leaving no residue and to remove any diseased mucosa and bone. To this end the minimum amount of bone is removed to gain safe access. The objectives can be achieved via anendauralor apostaural incision. Wherethere is mastoid involvement, theposterior meatal wall is removed andthe facial ridge must be taken down to the floor of the EAM; thus the mastoid cavity does not form an independent sump. Ideally, the middle ear cleft should be left as an air-containing cavity not open to the EAM. Incision

1 An endaural incision has the advantageof being small and, if well performed, healing with practically no scar. The author uses a postaural incision only for the translabyrinthine approach to acoustic neuromas, for facial nerve decompression, cortical for mastoidectomies and in cases where there is a risk of

Fig. 12.2 Endaural incision.

Mastoid Surgery

69

Fig. 12.3 Resection of redundant peripheral canal skin. (a) Deepening incision to allow temporalis fascia graft to be taken. (h) Elevation of periosteum. (c) Mastoid exposure and excision of excess canal skin.

S To develop the skin incision when dissecting deeper, go anteriorly to avoid cutting auricular cartilage. The anteriorauricular vein will be identified, diathermied and divided. Divide also the anterior auricular muscle and then identify the temporalis muscle.

Graft 1 Identify the temporalis fascia. A dense layer of areolar tissue, suitable as graft material, overlies the actual fascia, and may be utilised if thick enough. If not, take the fascia itself. The surface of the fascia can be finally cleared with a large periosteal elevator. 2 Insert in a three-pronged self-retaining retractor and at the upper end of the incision a double skin hook is held by the scrub nurse. Take the graft using toothed forceps and a scalpel with 15 blade, trim off any fat with a scalpel blade, and try to take a roughly circular graft as large as possible, using the full extent of the incision. 3 The graft may need thinning at its inferior edge (use a vein press to flatten) and is left to dry. Haemostasis should be secured to prevent haemorrhage into the operating field during surgery.

Soft-tissue exposure 1 Using a Rosen's elevator or small periosteal elevator, wall down elevate the skin off theposteriormeatal to themouth of thecholesteatoma sac andthen

elevate inferiorly to free the skin from the floor of the EAM. 2 Using a large periosteal elevator, elevate the soft tissues from the temporal bone anterior to the root of the zygoma, and posteriorly and inferiorly to bare the mastoid. 3 Using iridectomy scissors, remove a triangle of skin, with thebase at the superior posteriorrim of the circumferential incision and its tip at the spine of the Henle (Fig. 12.3). Removal of this superficial meatal skin posteriorly improves access, prevents the mastoid cavity being lined with hairs and ceruminous glands and improves surgical access. 4 Adjust the four-pronged retractor in the skin incision and open a two-pronged retractor at 90" to the fourpronged one. At this stage the mastoid and posterior meatal well should be clearly exposed. If tissue is still adherent to the spine of the Henle, dissect it off with a Rosen's elevator.

Bony exposure 1 Take a cutting burr aslarge as the access and visualisation will permit. Use the microscope at low magnification. 2 Before drilling, always check that the burr is secure in the drill and apply the power gently to check that the burr rotates in forward mode.Always drill from deep to superficial. Always have good vision of the deepest spot

70

Chapter I2

where you apply the burr.Use the drill like a paint brush with gentle pressure and multiple shallow strokes. With cutting burrs, always have the drill up to speed before applying to bone to reduce the risk of ‘kicks’. 3 In your other hand have an angled Zollneraural sucker, placed at the most dependent part of the operative field. If the drill does not have its own water supply, ask the scrub nurse or assistant to drip water from a syringe. 4 Drill away the spine of Henle and then from theedge of the sac, with each stroke coming the full length of the EAM. It is most importantthat a ‘pothole’ is not formed, as this restricts visualisation and access. You should be aiming to saucerise the field such that a good view of the deeper aspect of the dissection is visible at all times. 5 As the posterior wall is thinned, the incus will come into view. If care is not taken, the incus may come into contact with thedrill and, if the ossicular chain is intact, sensorineural hearing loss may be caused. If preoperativeaudiometry indicates an ossicular discontinuity, then one can afford to be less careful. 6 It is safe to use a diamond-paste burr until the whole of the incus is exposed. Besides being safer, diamond burrs also have the advantage of stopping haemorrhage from bone, the disadvantage being that they are slower. However, ‘it is better to be a safe mastoid surgeon than a fast one’; therefore always err on the side of caution, as speed should come with experience. 7 The aim is to remove only enough bone to allow the cholesteatoma to be removed safely and completely (Fig. 12.4). With a small cholesteatoma, very little bone may be removed (i.e. only the outer attic wall), thus producing an atticotomy. Sometimes it is possible to leave the incus in situ, but, if there is any doubt about the extent of the cholesteatoma, remove it. Remember if you are lateral to the incus the VI1 nerve is safe. 8 If the sac is more extensive the incus will have to be removed, and in these circumstances the long process of the incus will usually be absent. It can therefore safely be removed by dividing the ligament of the short process with a sharp needle or sickle knife and thengrasping the body with fine alligator forceps. Bone should then continue to be removed to give access to the sac. 9 To avoid tearing the sac it can be elevated from the bone using a House whirlybird. Keeping the sac intact makes following it easier and complete removal more likely, and is aesthetically more pleasing. l 0 As the dissection proceeds, the wall of the EAM is taken down to the floor. Knowing the facial nerve will lie deep to the anterior end of the lateral semicircular canal, use this landmark as a depth indicator. When

taking down the facial ridge use a diamond burr, with ample irrigation in order to prevent the bone heating up and damaging the nerve. Always drill along the long axis of the VI1 nerve, never across it. In its mastoid portion the nerve is deep in bone, and can be safely taken down to the level of the floor of the EAM. 11 If you drill too deeply, the nerve sheath will be encountered and is easily recognised by the blood-vessels on the surface. No harm will come if you are alert and drilling longitudinally withadiamondburr,but drilling transversely with a cutting burr is a recipe for disaster. 12 Air cells posterior to the VII nerve when filled with mucosa can cause confusion and be mistaken for the facial nerve. Drill gently, in the line of the VII nerve, and most air cells will be obvious. If in doubt (which we all are at times), use a whirlybird to palpate and dissect; mucosa is soft and will dissect out, while the nerve sheath is tough and fixed. 13 Take the facial ridge down so that the floor of the EAM and the mastoid cavity are in continuity (Fig. 12.5). This is vital since a high facial ridge is the most common cause of an ear that continues to discharge when the cholesteatoma has been completely removed. 14 In reality, however, it is only with practice on temporal bones, by watching others and by operating oneself that one really recognises when the overall cavity ‘looks right’, fora three-dimensional appreciation is required. The commonest mistake is to underestimate the depth of the facial nerve, thus leaving a high facial ridge. Specific areas Course of the facial nerve

1 The course of the facial nerve is crucial to middle ear and mastoid surgery. The anatomy can only be learned on temporal bones, starting in the temporal bone room. The basic principle is to find some identifiable structure to give anatomical bearings and dissect from this areato the likely site of the facial nerve. 2 Identify the short process of the incus: the facial canal will be just anterior to this. Dissection anteriorly should be done by moving the dissecting instrument along the line of the nerve not across it. This is a very dangerous area and the nerve may be dehiscent and camouflaged by white cholesteatoma matrix,so proceed with caution and ignore the passing of time. 3 If the stapes or oval window is more easily recognised, dissect posteriorly, observing the aforementioned rules.

Mastoid Surgery

Fig. 12.4 Sequential bone removal determined by the extent of underlying cholesteatoma. Progressive anterior-to-posterior dissection staying lateral to exposing cholesteatoma, thus creating atticotomy (1-2), atticoantrostomy (3) and mastoid cavity (4-5). (a) Bone approach for atticotomy. (b) Limited attic cholesteatoma pocket exposed. (c) Atticoantrostomy. (d-h) Extender exposure for large cholesteatoma producing mastoid cavity.

4 If neither of the landmarks canbe identified, then find the tegmen and dissect anteriorly, for if the facial canal has been eroded it is less likely to have been so superiorly, although this is not invariably the case. 5 The facial nerve is most vulnerable to drill-damage in its middle ear course, the burr being taken across it at 90" to its long axis. The next most vulnerable area is where it is adjacent to the anterior end of the lateral

71

semicircular canal; here it is quite superficial and can be damaged as the facial ridge is taken down. To reduce this risk, ensure that the facial canal in the middle ear segment has been cleared of cholesteatoma and granulation tissue and is clearly visible, use a diamond burr as big as access and visibility will allow, and drill along the course of the nerve. Tegmen tympani

1 Bone should be removed to expose the tegmen, as it is a very useful surgical landmark. Once the edge of the outer attic wall has been taken down to within 2mm of the tegmen, use a diamond burr. Take the remaining bone down with strokes along the free edge, not across it.

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Chapter 12

Fig.12.5 Lowering facial ridge and shaping mastoidectomy.cavity.

2 Oncethe

tegmen has been identified, remove any cholesteatoma. Underlying granulationsareoftenadherent to bone and exposed dura. Use the diamond burr to carve the natural contours of the tegmen as this will remove the granulation tissue and any diseased bone. If dura is encountered, it will bounce off the burr without being breached. 3 If a small hole is created, plug itwithtemporalis muscle. If the breached area is not well supported with bone, it is then necessary to elevate the dura from the tegmen and put in a temporalis fascial graft so that its edges aresupported by bone. Theremustnot be a cerebrospinal fluid (CSF) leak at the end of the procedure, so, if all else fails, consult a neurosurgeon-a very rare event. If there is a significant prolapse of dura into themastoid and temporal-lobeherniation is a likely outcome,thenthe mastoid must befilled witha temporalis muscle flap.

tissue, paying particular attention to the facial nerve, which may be dehiscent, the stapes superstructure or, if this is absent, the oval window. 3 Granulations are often firmly adherent to underlying structures and haemorrhagic. If bleeding is troublesome, apply a pledget soaked in 1:1000 solution of adrenaline and leave for 3min. To find a tissue plane, identify an adjacent portion of the bony facial canal and dissect from this into the granulations.Use a sharp needle to cut adhesions to bone and then advance the edge of the granulations with a whirlybird. 4 One has to balance the risk of facial nerve damage or causing adeadearagainst complete removal of granulations, so ‘discretion is the better part of valour’. Granulations usually settle down once the cholesteatoma has been removed.

Facial recess and sinus tympani

Thesacoften lies deep to the head of the malleus. Follow the sac as far as possible, identify the neck of the malleus, dissect off tissue until the jaws of a pair of malleus-head nippers can be inserted, cut off the head and remove it. The dissection canthen be continued anteriorly.

1 It is vital that, once the facial ridge has been taken down in order to gain access, thefibrousannulus is elevated. The pyramid of bone anterior to the facial canal, inferior to the stapes and posterior to the round window is removed with a small diamond burr, drilling in line with the facial nerve (Fig. 12.6). 2 The usual problem in this area is granulation tissue underlying the sac. First remove the sac and, when this has been achieved, assess the extent of the granulation

Malleus

~ y p t o t y ~ p a n uand m mesotympanum Dissect from posterior to anterior, noting that itmay be necessary to remove bone from thebony annulus togain

Mastoid Surgery

\in sinus tympani

73

Section

Fig. 12.6 The sinus tympani.

better access. The roundwindow is usually protected by a bony overhang; the bone over the promontory may have been eroded so dissection must be gentle.

Eustachian tube Occasionally the sac invades the Eustachian tube. One can only remove as much matrix as access allows.

Air cells How much polishing of the mastoid aircells is desirable once the sac and granulations have been removed? In a well-pneumatised bone, it is impossible to saucerise all the air cells and remove all mucosa. One should aim to produceamastoid cavity with fairly smooth walls, which has no gross overhangs or projections and where all areas of osteitis have been removed. Labyrinthine fistula

This should be suspected in all cases of cholesteatoma, the most likely site being the lateral semicircular canal. A fistula may be visible once the debris has b.een removed from thesac or palpated with a blunt instrument, such as a whirlybird. The lateralsemicircular canal may just have been ‘blue-lined’ and, if this is over a segment of about 2 mm or smaller, it is possible to remove the sac from the underlying endosteal membrane. Whenthe sac has been removed completely, the fistula should be covered withthetemporalis fascia

graft. If there is a large defect and/or the patient was vertiginous and fistula-sign-positive preoperatively, a cap of cortical bone should be fashioned to cover it. With longer fistulae, it may not be possible to remove the adherent cholesteatoma withgentle dissection and in these circumstances a small island of skin should be left in continuitywiththemastoid cavity and thearea should not be covered. If the endolymphatic space is exposed accidentally, avoid suction over the site and pack immediately with muscle. Cholesteatoma invading the labyrinth (which if left will result in the persistence of symptoms) is the real dilemma, particularly if there is useful hearing in the ear. Removal of the sac will almost certainly result in a dead ear. If discovered at surgery, which is most probable (because CT scanning of the ear is not justified in the vast majority of patients, due to radiationexposure and expense),thenoneshouldstoptheprocedurewitha view to discussing the exact implications with the patient. Although the patient has been warned that ‘ear surgery can result in total deafness but the risk is small’, in this situation this warning is no longer valid and a small risk has turned into a near certainty. The author therefore thinks that the patient should be aware of this and be party to the clinical decision-making. Losing the way

Anyone can get lost in an ear and if this happens one should stop operating and go down tothe lowest-power

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Chapter l 2

lens on the microscope. Get an overview of theear, identify the malleus handle, the floor of the EAM, the tegmen and the lateral sinus; this should thengive you a mental picture of where the facial nerve is. If you arestill lost, close the ear up if no expert advice is available. During training there should always be a consultant in the operating theatre or elsewhere in the hospital available for advice. Grafting

1 The purpose of the graft is to give an enclosed aerated middle ear,which prevents mucoid discharge with URTI. Never graft if the wholeof the cholesteatoma has not been removed. 2 The graft should be placed as an underlay from the posterior edge of the tympanic remnant anteriorlyto the bony facial canal posteriorly, laid on a bed of surgical sponge. If a radical mastoidectomy has been performed, the anterior end of the graft should be placed in contact with the lateral edge of the Eustachian tube. The graft should be supportedwith small pieces of surgical sponge. 3 The graft should be laid on the stapes head if present, but if, due to the anatomy, it does not lie easily on the head of the stapes then piece a of cortical bone should be positioned between thestapes head and thegraft to form a type 111 tympanoplasty. 4 Staining thegraftwith methylene blue allows its ready identification and helps with accurate positioning, and all novices should use this trick when grafting an ear. The graft should be finally covered with a single compressed piece of surgical sponge. Closure The skin incision should be closed with a continuous subcuticular 410 PDS, starting superiorly and finishing in the EAM. Six inches (15cm) of a half-inch BIPP pack is inserted gently and not packed tightly, since removal of a pack is unpleasant, so do not make it niore so by using 1 inch (2.5 cm) gauze and tight packing. The incision should be covered by a piece of Melolin. A gauze dressing containing cotton wool should be applied to the pinna followed by a 3 inch (7.5cm) cr6pe bandage, use ribbon laid flat beneaththebandage above the ipsilateral eye to prevent thebandagespreading and covering the eye. Check that the crcpe is not tootight to avoid pressure necrosis of the skin.

1 The presence of facial movement should be checked before the patient leaves the operative recovery room. 2 The patient should be allowed to drink and eat as soonas fully conscious and wishing to.Thepatient should be kept overnight; the following morning do the Weber test to check that the operated ear is still functional. Check for nystagmus and bleeding. If the patient is not vertiginous and has regained normal ambulation, discharge home. 3 Remove the bismuth, iodoform and paraffin paste (BIPP) pack 2 weeks postoperatively and check the operative wound and ear for infection. It is not necessary to repack theear,although some surgeons have this bizarre ritual. If you feel a pack needs to stay in longer, then leave it in place. The author has seen a patient 4 months after a modified radical mastoidectomy for the first postoperative clinic visit (due to a clerical error). On removing the pack, the mastoidcavity was found to be completely epithelialised and healed. 4 Using absorbable sutures obviates the need for suture removal and in 9 years using absorbablesuturesthe author is not aware of any wound breakdowns due to infection. 5 On removing the pack, show the patient the BIPP so that helshe does not confuse it with mucopus. At this stage the cavity and graft will be covered with surgical sponge and blood clot, and therefore the ear cannot be assessed. 6 A more detailed assessment is made in a further 6 weeks, when a pure-tone audiogram (PTA) with proper masking should be performed. Review againin 3 months and, if the ear and audiogram are stable, then review again in 6 months. '7 Oncetheearhas been stablefora year, discharge from the clinic and warn the patient that,if the hearing deteriorates, tinnitus develops or worsens, vertigo develops or persistent discharge or bleeding occurs, he1she should be referred back for review. Give the same information and instructions to the patient's GP.

This could be due to lignocaine from the initial injection coming intocontactwitha dehiscent facial nerve or due to a tight pack compressing the nerve. In the first case, wait, since there should be recovery in 2-3 h; in the second case, loosen the pack. Surgical damage may of course be the cause and, if there is any doubt or there is

Mastoid Sztrgery no recovery in 2-3 h, theearshould be re-explored immediately. In delayed oedema and palsy, remove the pack and wait, since this will always recover. Inform the consultant in charge immediately ifVI1 palsy occurs, whatever you think may be the aetiology.

This is rare,as is perichondritis. If thelatter occurs, then the patient shouldbe given intravenous antibiotics (e.g. Augmentin),thewound re-explored andany dead cartilage removed. Granulations are not uncommon onthewound edge inside themastoid oron the surface of the cavity itself. Treat in out-patients with silver nitrate cautery and the application of antibiotic cream at 2-week intervals untilthe infection is settled.

In the immediate postoperative period, nystagmus, vertigo, nausea and vomiting are all more likely to be due to the effects of the anaesthetic. If these have not settlled by the following day, then assume an otogenic cause. If theear is still functioning,thenminortraumawhen drilling around the lateral semicircular canal is likely. If there is adeadear,alabyrinthine fistula should be assumed; hence giveIV antibioticsand, if there is a possibility that a fistula was missed at the original surgery, theearshould be re-explored and the fistula packed with muscle. eafness

Partial deafness in the postoperativeperiod is difficult or impossible to assess, since, even when the pack is removed, oedema and blood clot may still result in temporary a conductive loss. By about 6 weeks postoperatively, a reliable audiogram can be obtained. On occasion, the cholesteatoma bridges from the incus to the stapes, allowing sound conduction, so that surgical removal causes a loss of hearing. A dead ear may be a result of the cholesteatoma's erosive behaviour or the result of indelicate surgery. Ti~nitus

If this develops postoperatively, then it may be due to

75

the middle ear environment, and in some patients it is due to awareness of their own internal carotid pulsation. Temporary middle ear causes will usually resolve in a few weeks.

This is very rare but a potential severe risk that should always be considered if apatient has unexplained pyrexia or headache, if recovery is slow or if severe nausea and vomiting, nystagmus or catastrophic tinnitus occurs.

The most common cause of postmastoidectomy aural discharge is a high facial ridge. If the facial ridge has been properly lowered, then residual cholesteatoma should be suspected, which wouldrequire revision surgery. A cavity that fills with wax and is not selfcleansing may also give rise to intermittent infections. This is due to ceraminous glands occupying the cavity and is avoided if themeatal skin has been properly excised at surgery. Discharge may also occur if the middle ear cleft has not been grafted or the graft has broken down.Myringoplasty should be considered in these cases.

The modified radical mastoidectomy is the mainstay of treatment for cholesteatoma and if performed properly will result in a clean dry cavity. If this is maintained for 2 years, the patient has no need for regular follow-up. Small cavities are best achieved by following the cholesteatoma as described, via either an endaural or a postaural incision. This technique obviates the need for mastoid obliterations, meatoplasties and long-term cleaning of the cavity.

Dawes JDK(1976) Epityrnpanotomy and tyrnpanornastoidectomy. In: Rob C & Smith R (eds) Operative Surgery: Middle Ear and Mastoid. London, Butterworths, p. 56.

he astoid

3

A N ~ R E WVAN HASSELT

Revision procedures attempting to control discharging mastoid cavities are numerous and will all enjoy a limited measure of success. However, to ensure a rewarding outcome, basic surgical rules must be applied. First, all diseased tissue must be removed with meticulous care under magnified vision. Second, a smoothly contoured, physiological bony cavity should be created devoid of ridges or recesses. Third, in order to resurface the bony mastoid cavity with durable epithelium, the bare bone and mucous membrane should be covered with a fertile layer upon which the epithelial covering may thrive. This is achieved by lining theentire bony cavity witha vascularised, living layer of deep temporalis fascia. This pedicled flap provides a tough, permanentlayer of fascia that protectsthe bone and mucousmembrane while providing a stable nourishing foundation for the surface epithelium. Finally, the ear canal should be widened to provide adequate ventilation and inspection of the new mastoid cavity (van Hasselt, 1994). This procedure has become known as the ‘Hong Kong flap’ technique for mastoid cavity reconstruction. In reality a very small number of revision mastoid operations are performed by the original surgeon. The procedure is hazardousasthe previous surgery may have distorted useful landmarks and important structures may be exposed.

The indication is the troublesome moist cavity, particularly in the young, active patient.

1 When the patient is medically unfit.

2 Previous fistula has been noted but the patientstill has useful residual hearing.

reparation Whenplanning revision mastoidectomy, every effort must be made to obtain the original operation record. Any and every detail of the first procedure is useful knowledge to the surgeon. A current CT scan of the temporal bone may be helpful in showing distortion of the anatomy and the positions of important structures. Detailed knowledge of temporal-bone anatomy and recognition of tissues and their textures areessential assets in this situation. The harvesting of living fascia for the reconstruction in order tocreate a lining for the mastoidcavity requires a clear understanding of the muscular and fascial layers of the temporal region (Abul-Hassan et al., 1986). The patient is placed in the standard position for ear surgery.

e procedure Infiltration with a vasoconstrictoris useful prior to making the incision. Theauthor’s preference is for an endaural incision that is extended high and curved backwardsfor 3-4cm abovethemeatus (Fig. 13.1).The lower incision extends laterally from deep inside the meatus at 7 o’clock in a right ear. Thetwo incisions are joined as close as possible to the annulus. Sometimes no lower incision is necessary in a large cavity where awide meatus exists. The incision is deepened by sharp dissection to the temporal bone at the lower end but onlydeep enough to expose the deep temporalis fascia at the upper endof the

Surgery of the DischargingMastoid

77

Fig. 13.1 The incision.

wound. Healthy skin between upper and lower incisions in theposteriormeatusshould be saved, creatinga posterior meatal skin flap. A self-retaining retractor is inserted to expose themastoidarea and a periosteal elevator is used to raise adherent tissue, thusaiding exposure. Any unhealthy tissue should be removed. In order to gain adequateaccess to the mastoid, itis almost always necessary to remove some regenerated bone. This should be done carefully, starting at the lip of new bone and moving backwards and medially, thus creating or reopening the mastoid bowl. Careful dissection of the mastoid contents is undertaken with a suitable elevator using theoperating microscope, always watchingfor exposed lateral sinus or middle cranial fossa dura. As one proceeds from behind forwards, the lateral semicircular canal, facial nerve and other middle ear structures are encountered and identified. It is important that the surgeon identifies each landmark and uses it as a reference point as the operation progresses. Any healthy middle ear structure is saved. The outer rim of bone forming the upper margin of the cavity should be taken down almost to the depthof the middle fossa dura from the root of the zygoma anteriorly to the posteriorlimit of the cavity behind (Fig. 13.2). This allows for free placement of the pedicle of the flap and a well-proportioned cavity. The author is of the firm opinion that all mastoid air cells do not require drilling and exenteration. Healthy mucosal pockets may be left in situ. Furthermore, the

Fig. 13.2 The upper ridge of bone taken down to the middle cranial fossa dura.

cavity should not be polished to a smooth finish. with a diamond burr as this may devitalise the bone surface and interfere with the nutrition of the graft bed. Oncecompleted,the cavity is loosely packed with adrenaline-soaked ribbon gauze while the pedicled deep temporalis fascia flap is fashioned. Large self-retaining retractors are placed in the upper wound over the flap. Lateral traction of the overlying tissue aids wide bluntfinger dissection to free the lateral surface of the fascia. A horizontal incision in the lower border of the fascia allows introduction of a Freer dissector beneaththe fascia and blunt cleavage from the underlying temporalis muscle (Fig. 13.3). The incision in the fascia is then extended backwards and continued adjacent to its attachmentto the skull behind and abovethe temporalis muscle and then down to reach the zygomatic arch anteriorly, taking care to ensure preservation of a 1cm pedicle (Fig. 13.4). The middle temporal artery on which the flap is based is not specifically identified. The flap is then released from the fattytissue, tethering it on the deep surface of the pedicle. If raised, the ramifying vessels can be observed spreading into the flap (Fig. 13.5). A 1.5cm groove is created with cutting diathermy in the lower edge of the temporalis muscle just beneaththe pedicle to accommodatethe fascial pedicle (Fig. 13.6). Theflap is then swung into thecavity without twisting or rotatingthe pedicle. The lower edge

Fig. 13.3 Freer dissector passed through an incision in the lower edge of the deep temporalis fascia showing blunt cleavage from the muscle below.

Fig. 13.5 Raised flap with ramifying vessels.

Fig. 13.4 The flap with a 1cm pedicle.

Fig. 13.6 A 1.5 cm groove cut in lower edge of temporalis muscle.

o f the flap is placed deep to thetympanicmembrane (TM)remnant. It is important to preserve what remains of the TM andanterior annulus asthis willprevent lateralisation. Posteriorly the facial ridge forms a natural buttress to support the flap. Reconstruction o f an ossicular conducting mechanism is feasible as a primary

procedure. Thereconstructedchain should protrude only slightlybeyondthe facial ridge,ensuring good contact with theoverlying flap. Once the flap is in place, the superior canal skin, TM remnant and lower canal skin are placed over the edges o f the flap, ensuring that allexposedbone is covered. The deeper part of the

Surgery of the DischargingMastoid

73

enabling any recurrence of disease to be clearly identifiable. Recurrent or residual cholesteatoma appears as a pearl, which can be removed as an out-patient procedure.

BIPP allergy and haematoma beneath the upperincision have been occasionally encountered.Other complicationsarethose associated with mastoidectomy (see Chapter 12).

Fig. 13.7 Sling-stitch meatoplasty.

cavity is then packed with bismuth, iodoform and paraffin paste (BIPP) impregnated ribbon gauze. This ensures contact between the conchomeatal skin, the fascial flap and the underlying bone. The meatoplasty involves threesteps (Fig. 13.7’) (Tong et al., in press). First, sharp dissection is used to expose and excise the upper 3-4mm of tragal cartilage, which has a natural curve into the upper meatus. Second, a ‘sling stitch’ is inserted through a stabincision 23cm above and behind the pinna. The absorbable stitch catches the cartilage of the helix, drawing it away from the meatus when firmly tied. Finally, the lower end of the wound is left open, the upper woundbeing closed in two layers.’Packing of the cavity and meatus is then completed. The wound is not routinely drained.

A firm circumferential dressing is applied for 24 h. The BIPP pack is removed 2-3 weeks postoperatively and topical antibiotic with steroid drops are then applied for 1 week. Epithelial coverage of the vascularised flap follows rapidly over the following weeks. If the migratory epithelium of the T M and ear canal has been preserved, the cavity will‘ become self-cleaning. Within 6-9 months, the flap lining the cavity becomes transparent,

Should a postauricular approach be strongly indicated or favoured, the postaural incision should be extended superiorly above the pinna in order to allow access to fashion the vascularised temporalis fascia flap. The procedure is otherwise as described, but a wide appropriate meatoplasty should replace the ‘sling stitch’ procedure as the latter is not possible via this approach. A number of alternative techniques for lining or obliteratingand lining themastoid cavity have been described. The superficial temporoparietal fascia is a viable alternative living layer with which to resurface themastoid cavity (East et d., 1991; Cheney et al., 1995). Theblood supply for this superficial fascial layer is derived from the superficial temporal vessels. Successful mastoid obliteration has been achieved by filling the revised cavity with autologous bone pate, which is then covered by a temporalis musculoperiosteal flap (Moffat et al., 1994). The author does not believe that this is necessary and would warn that pockets of residual or recurrent disease may be buried within an obliterated cavity.

eferences Abul-Hassan HS, von Drasek Ascher G & Ackland RD (1986) Surgical anatomy and blood supply of the fascial layers of the temporal region. Plastic Reconstr. Surg. 77, 17-24. Cheney ML, Megerian CA, Brown MT & McKenna MJ (1995) Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 105, 1010-13. East CA, Brough MD & Grant HR (1991)Mastoid obliteration with the temporoparietal fascia flap. J.Laryngol. Otol. 105, 417-20. Moffat DA, Gray RF & Irving RM (1994) Mastoid obliteration using bone pate. Clin. Otolaryngol. 19, 149-57. Tong MCF, Liu KC & van Hasselt CA (in press). Sling stitch meatoplasty. Laryngoscope. van Hasselt CA (1994) ToynbeeMemorial Lecture 1994: mastoid surgery and the Hong Kong flap. 1.Laryngol. Otol. 108, 825-33.

Osseo-integrated Implants MICHAEL P. ROTHERA

Osseo-integrated implants are now an established method for attaching bone-anchored hearing-aids (BAHA) and high-quality prosthetic ears. The technique can also be used for other more specialised craniofacial prosthetic reconstructions. Branemark’s original work onosseo-integrated dental implants was developed by Tjellstrom to allow a stable percutaneousimplant.The technique relies on the atraumatic insertion of a titanium screw fixture into the temporal bone. Provided the osteocytes immediately adjacent to the implant surface are not damaged, direct integration occurs, which can eventually withstand high levels of physical stress. The process is completed by attaching an abutment through the skin to the boneanchored fixture. Adequate soft-tissue reduction at the site of skin penetration is the single mostimportant factor in achieving a stable and infection-free implant.

6 Patients with severe otosclerosis in an only hearing ear or as an alternative to stapedectomy in difficult cases. Thereare two types of Noblepharma BAHA: the HC300, which is a self-contained unit attached directly to animplant, and the more powerful HC220, wherean implant-retained transducer is powered by a body-worn aid. The audiological criteria for selection are as follows: 1 the HC300 may be useful wherethe average BC thresholds at 1, 2 and 4 kHz are less than 45 dB, with speech discrimination greater than 60%; 2 the HC220 may be useful where the average bone conduction (BC) thresholdsover 1 , 2 and 4 kHz are less than60dB, with speech discriminationgreater than 60%. Contraindications

Bone-anchored hearing-aids

1 There are few specific contraindications provided the audiological criteria are fulfilled and the patient is fully informed, but severe eczema or established keloid formation presents obvious problems. 2 Implantsare rarely considered below the age of 5 years because of inadequate bone thickness.

Indications

Patients with abilateral conductive-hearing loss who are unable to use a conventional air-conductionhearing-aid (ACHA) are potential candidates for a BAHA. 1 Bilateral congenital conductive-hearing loss with or without previous attempts at reconstruction. 2 Bilateral meatal stenosis. 3 Bilateral chronic supporative otitis meatus (CSOM) unresponsive to conventional surgery and where an ACHA causes discharge. 4 CSOM in an only hearing ear which becomes active when an ACHA is used. 5 Patientswith severe bilateral otitisexternamade worse with an ACHA.

Bone-anchored artificial ears Indications

Auricular prostheses can be attached to similar osseo-integrated implants to provide a secure and realistic pinna.Potential cases include thosewiththe following: 1 severe microtia; 80

Osseo-integrated Implants

2 traumatic loss of the ear; 3 loss of the ear due to tumour surgery.

Contraindications

1 Therearefewcontraindications in patientswitha completely absentpinna.However,wherethere is a rudimentaryear(particularlywitha well-developed lobuleinthecorrectposition)careful counselling is necessary before deciding to remove it. Patients should have the opportunity to meet and discuss the technique with people who have completed implantation. 2 It is difficult to find adequate bone for implantation below the age of 7 years and, for psychological reasons, it is probably best to delay surgery until at least the age of 11. 3 Implantationafterradiotherapyhasaconsiderably lower success rate due to problems with osseointegration.

Preoperative management for bone-anchored hearing-aids Patientsshould have amaskedpure-tone and speech audiogram. Free-field audiometry comparing a conventional ACHA and the HC300 using a perspex bite bar (which is held between the teeth and transmits sound vibrations via the upper jaw) is useful and gives patients an idea of the type of hearingtheycanexpectafter implantation. Factors which influence the side of implantation include the following: 1 the side of best cochlear function; 2 whether the patient is right- or left-handed; 3 the side of preferred telephone use; 4 the side of the worse pinnaso that an HC210Bi-Cros, which fits behind the pinna, can be supported by the better ear.

Preoperative assessment for bone-anchored artificial ears Inpatientswithmicrotiacertain specific features are checked. 1 Preoperative facial-nerve weakness or a loss of the normal distance between the mastoid and temporomandibular joint (TMJ) withan absent meatus increases the risk of an aberrant facial nerve. 2 An anteriorhairline may requireskingrafting to avoid hair follicles around the implants. 3 Periauricular sinuses may need to be excised with a remnant pinna at the second stage to prevent epider-

8I

moid formation. The deeper tracks have a potentially close relationship with the facial nerve. 4 A three-dimensional CT scan is helpful in complex cases to plan the site of implantation and identify the course of the seventh nerve. The role of the implant team, which should include an audiologist, prosthetic expert and surgeon, is to act as an information centre, ensuring that the patient and,in the case of children, their parents, are fully informed about the technique and results of implant surgery and have a clear understanding of the long-term commitment that apercutaneousimplantdemands.They should also be aware of alternative treatments, which include doing nothing or considering plastic surgery.

Relevant anatomy The lateralanatomy of thetemporalbone is well known.In cases of congenitalmicrotia,particularly where there is an absent meatus, the courseof the facial nerve fromthe secondgenu can be variable.Poorly developed mastoidsshould be regarded in a similar fashion to the situation encountered in infants, where the facial nerve can emerge laterally and at anunexpectedly high level. The ideal position for BAHA is one that allows the anterior border of the aid to lie parallel and a couple of millimetres behind the posterior rim of the pinna. Adequate bone canusually be found in a line which continues posteriorly from the suprameatal crest. Two fixtures are used for a bone-anchored artificial ear (BAAE). The preferred position is between 11 and 18mm from thecentre of the meatus at 8 and 11 o’clock on theright and at1and 4 o’clock on theleft (Fig. 14.1). Local factors will invariably affect the final position, but as much space as possible should be left between the implants to facilitate cleaning and reduce the distance the gold bar has to extend beyond the abutments.

Operative technique In adults theBAHA and BAAE can be performed under local anaesthetic with diazemolor midazolam sedation. If surgery is expected to take more than 1h, a general anaesthetic is preferred.Patientswithcongenitalear disease associatedwithmicrognathiacan be difficult to intubate and a fibre-optic laryngoscope is a useful ad~unct. Prophylactic antibiotics are not used in the two-stage procedure but Augmentinisprescribedin single-stage surgery, as the osseo-integration interface is in continuity withthe site of skinpenetration.Thepatient is

82

Chapter l 4

Fig. 14.1 The two fixtures used for

a

bone-anchored artificial ear.

Fig. 14.2 Bone-anchored hearing-aids-3 cm incision.

placed in the routine position for mastoidsurgery. In all cases of BAAE the face is exposed and covered with a plastic drapeand anon-paralysinganaesthetic employed so that facial nerve function can be monitored. For a BAHA, the skin is shaved for 2cm beyond the proposed site of skin grafting and for a BAAE for 12 cm behind the postauricular hairline.

Incision

The dummy BAHA is placed in the correct position and the ideal site of implantation marked. A 3 cm incision is made in a straight line (Fig. 14.2) through the layers of the scalp to the periosteum, which is left intact. A s,elf-retaining retractor is inserted and a 3mrn guide drill is used to identify a suitable area of bone by drilling directly through the periosteum, using circular motion to make the hole slightly larger than the drill. A probe is used to check the base of the hole and if bone is still present the drill is increased to 4mm. Successful integrationdepends on maintaining viable osteocytes adjacent to the flange fixture and all drilling must be accompanied by cooling irrigation with normal saline. If a large air cell, dura or the lateral sinus is encountered, a new guide hole is drilled at least 3mm away. Ideally a 4mm implant should be used, but 3 mm implants are satisfactory and it is rare to find more than

this depth of bone in children. Partial entry into acellular system is not acontraindication to implantation provided there is at least 2.5mm of cortical bone. Once a suitable site has been identified, the periosteum is divided with a small cruciate incision and reflected just beyond the diameter of the countersink drill, which is used to widen the hole to 3.7’5 mm. If possible, the surface bone around the hole should be countersunk for at least 75% of the circumference to allow the flange as well as the screw tap to make close contact with thebone. Continuous irrigation is required and bone that collects withinthedrill grooves must be removed at frequent intervals to prevent excessive heating. A titanium screw tap of the appropriate size isused at slow speed (0-12rpm) with an automatictorque-release drill to cut an exactthreadinthe hole. Irrigation is needed during tapping and reversal and can be used to gently wash out bone cuttings whichcollect in the depth of the hole before the flange fixture is implanted. It helps to place a small amount of blood within the hole to highlight the screw thread before aligning the implant. Irrigation is withheld until the fixture has engaged the thread, toprevent saline being forced into the haversian system of the bone. After theautomatic torque device hasstoppedthe drill, insertion is completed with a hand wrench, again with irrigation. The perforations in the implant flange are of a ‘spokeshave’

Osseo-integrated Implants design and can beseen to just bite into the- bone at completion. A spacescrewis inserted, the periasteum replaced over the implant and the scalp closed in asingle layer with 4/0 prolene.

If an air cell is encountered, implantation can still proceed provided there is at least 2.5rnrn of cortical bone. Screw tapping is stopped before the torque mechanism is activated and the final 1mm of flange fixture implantation is performed by hand to preventstrippingthe more delicate thread. Cases wherethere isless than 3mm of bone are left for at least 4 months before the second stage. e=a

e

This can take place after 3 months under local (LA) or general anaesthetic (GA). The skin around the abutmentneeds to be thin, free of hair and relatively immobile. The graft needed to replace thehair-bearingskin is approximately2cm in diameter and can be taken as a split-skin graft from the implant site or the inner aspect of the upper forearm or as a full-thickness graft from the postauricular region. The advantage of the first method is that onlyone operation site is used, but the precise location of the implantmust be accuratelydocumented at the first stage. The area is shaved as before and the skin to be removedis marked and infiltrated with LA to raise the area above the surroundingscalp as a plateau.A circurnferential subcuticular incision is made and the circle of split skin removed with a Hurnbyknife set to 3/6 on the dial. The incision is then deepened, sharply undercutting the surrounding skinto ensure adequatetissue reduction down to the periosteum. The implantis identified and theoverlying periosteum and any new bone growth which would interfere with abutment fixation is removed with the raspatory and the space screw partially removed. The adjacent periosteum is cleaned, haemostasis achieved with bipolar diathermy and the skin graft sutured back into position with 5/0 prolene, with the surrounding scalp bevelling down towards the graft. A punch is used to remove an exact area of skin for thepercutaneousabutment. The space screwallows easy identification throughthe skin and protectsthe fixturethreadfromthepunch.Thehearing-aid abutment, supported by the wrench, is attached, using the four-pronged screwdriver. The angle of the hearing-aid can be judged by the direction of the rectangular inden-

83

tation withintheabutment,whichcan be rotated in steps of 20". The gold-alloy screw can be tightened with as much torque as is possible to generate, holding the screwdriver between the thumb and forefinger. A healing cap is snappedintotheabutmentand half-inch (1.25 cm) ribbon gauze impregnated with Bactroban ointment placed around the abutment to exert gentle pressure onthe graft and adjacent scalp. A pressure dressing is applied for 24h.

After 1 week the cover cap is removed and the dressings taken down. The stitches canbe removed and a further light dressing of ribbon gauze and Bactroban applied underthe healing capfora week. Thereafterthe dressing isremoved butthe healing cap left in place forprotectionuntilthe BAHA is fitted at theend of the third week. Usually desquamated a layer needs to be removed from the graftat this stageand any accumulateddebris at thepercutaneousjunction is cleared witha22-gauge needle or stitchcutter. The patient is given instructions about cleaning and care of the implant site.

Provided careful attention is paid to the technique of flange-fixture implantation, failure of osseo-integration is extremely rare. Movement of the fixture when the abutment is attached suggests non-integration and the implant should be removed and replaced at anadjacent site. Minor episodes of erythemaarecommonuntilthe graft stabilises over acouple of monthsandcan be treatedwith cleaning and Bactrobanointment. Granulations and infection at the percutaneous site respondrapidly to oral flucloxacillin oran equivalent antistaphylococcal antibiotic. Inflammation at a previously stable site is nearly alwayscaused by a loose abutment and settles when the screw is tightened. Inadequate tissue reduction of the graft or surrounding scalp predisposes to movement between the skin and theabutment, which increases the risk of infection. Inflammation, particularly in children, causes subdermalregeneration,whichmakestheproblem worse.Itcan usually beresolvedby removing the abutmentfora fewweeks andthenreconnecting, using aeutecticmixture of localanaesthetic(EMLA) cream and the skin punch, but occasionally formal tissue reduction is needed. Pain around the implant is an ominous symptom of implant failure, but early abutment removal and flucloxacillin may save the day.

84

Chapter 14

rtificial ears The technique for flange-fixture implantation is essentially the same as for BAHA. In consultation with the prosthetic expert, ideal implant positions are planned preoperatively. A postauricular incision in the hairline is used and no attempt is made to reduce the softtissue or remnant pinna at the first stage. The periosteum is kept intact and exploratory guide holes drilled in the ideal positions. If suitablebone is found,thefixturesare implanted in the usual wayand the woundclosed. Often a number of sites have to be tried for the inferior implant due to mastoid pneumatisation. Depending on the quality and thickness of the bone encountered 3-6 months later, the second stage is performed. It is usually possible to use local skin, provided the hairline is in a normal position. Scarring fromprevious operations makes no difference. The incision can vary depending on whether the remnant pinnaneeds to be removed but a postaural approach via the original incision is usually satisfactory. A subcuticular incision is made, using a number 15 blade, the skin over the proposed implant site is raised as thinly as possible. Minor perforations do not matter they asallow any haematoma to escape. The skin should be thin for at least 1.5cm beyond the abutment and between the two implant sites. The soft tissues are removed for a similar distance downtothe periosteum,including anarea posterior to theincision, to allow the skin to bevel down to the graft. The remnant pinna is removed, if necessary with excess skin. If a tragus is present, it should be preserved to help camouflage theanteriorskinjunctionwiththe prosthesis, and occasionally a tragus canbe created with redundant cartilage. The fixtures are exposed, using a raspatory, and the space screws partially removed.The skin is sutured with S/O prolene and a 4 or S.5mm abutment attached after removing skin over the fixtures with a punch. Healing caps are screwed into place and half-inch (12.5 cm) ribbon gauze with Bactrobanused to apply gentle pressure to the peri-implant site. A pressure dressing is used for 24 h and is replaced before the patientgoes home with a lighter dressing, which is worn for the next week. After-care is the same as with the BAHA, but all the soft-tissue swelling must have subsided before an impressionis takenforprostheticfitment, usually at 4 weeks.Some patientscan feel self-conscious at this stage, particularly if a remnant pinna hasbeen removed. They require reassurance and may prefer a ‘bandanna’ dressing until the ear is fitted.

Single-stage implantation Several centres have performed BAHA and BAAE as a single-stage procedure, but this is only recommended in ideal patients and by surgeons who have already performed several two-stageoperations.Careshould be taken when attaching the abutment, and load-bearing should be delayed for at least 6 weeks. The operation is covered with Augmentin because of the risk of infection at the percutaneoussite affecting osseo-integration. The results appearto be satisfactory but long-term follow-up is awaited.

Alternative procedures The Audiant Xomed implantable hearing-aid may be considered for patients with relatively normal cochlearfunction and anormalpinna.Ithasthe advantage of avoiding a percutaneous implant, but retention of the aid and the level of amplification are less satisfactory. Plastic-surgical reconstruction of the pinna. has not generally been very satisfactory in the past, with many patientsundergoingmultipleoperations at ayoung age withpoor results. However,somepatients are suitable and techniques will undoubtedlyimprove. Before making adecision to have a BAAE, particularly if a remnant pinna is to be removed, patients should, as part of their informed consent, have the opportunity to discuss the realistic results with a plastic surgeon who hasan expertise in this field. There is usually good agreement about which techniqueis suitable for anindividual case.

Further reading Stevenson DS, Proops DW, Wake MB, Deadman MJ, Worrollo SJ & Hobson JA (1993) Osseointegrated implants in the management of childhoodearabnormalities:the initial Birmingham experience. J.Laryngol. Otol. 107, 502-9. Tjellestrom A (1990) Osseointegrated implants for the replacement of absent or defective ears. Clin. Plastic Surg. 17 (2), 355-66. Tjellestrom A & Granstrom G (1994) Long-term follow-up with bone anchored hearing aid: a review of the first 100 patients between 1977 and 1985. Ear Nose Throat J.73 (2), 21-3. Tjellestrom A & Granstrom G (199.5) One-stage procedure to establish osseointegration: zero a to five years follow-up report. J.Laryngol. Otol. 109, 593-8. Tjellstrom A, Jansson K & Anderson H (1993) Maxillo-facial

Reconstruction and Hearing Rehabilitation Utilizing OsseointegrationMethod:SurgeonsManual.

the

Goteborg: Implant Unit, Department of Otolaryngology, Sahlgrens Hospital, University of Goteborg.

Cochlear Implantation P. GERARD REILLY AND G E R A R D M. O ’ D O N O G H U E

Cochlear implantation is a well-established treatment modality in themanagement of carefully selected patients with profound or total sensorineural hearing impairment. In selecting patients for this treatment, a number of audiologicalandnon-audiologicalfactors must be considered.

Audiological considerations Cochlearimplantsareappropriate in patients who havegained no material benefit fromconventional amplificationwithoptimally fitted hearing-aids.This generally coincides with unaided hearing thresholds of greater than llOdB in the better-hearing ear. It is important that patients should have had a period of intensive auditory rehabilitation with optimally fitted hearing-aids before a final decision as regards implantation is made. Any conductive element to the hearing loss, typically a middle ear effusion, should be treated before a decision to implant is made, as even a mild conductive loss may prevent a patient benefiting from a hearing-aid.

Non-audiological considerations The followingfactorsaremajordeterminants outcome of cochlear implantation.

Duration of deafness

In general, ashorterduration of profound deafness meansgreaterpotentialfor successful adaptationto sensory assistance. Prolonged periods of sensory deprivation maycause irreversible atrophy of thecentral auditory system. Age of patient

It isvery difficult to assess with certainty the hearing thresholds in children under the age of 2 years. It is also difficult to estimate the benefit of hearing-aids in this age-group and it may takeseveral months to make these judgements. Although the middle ear and cochlea are of adult size at birth,theremainder of theskull is considerablysmallerandscalpthickness isless. This may lead to difficulty in positioning the implantreceiver and, because skin coveris thinner in the very young, great care must be taken to prevent device extrusion. Theimplant system in ayoung child mustalso be capable of accommodating subsequent head growth. Age per se is not a barrier to implantation. Elderly patients who have been implanted may be given sufficient hearing to enable them to live independently.

in the

Age at onset of deafness

Neuronal plasticity reduces with advancingage. Patients implanted at a younger age have greater potential for developing new neuronal connections, which facilitate the maintenance and expansion of the central auditory pathways.

Educational environment

For children, implant decisions should be made giving due consideration to the educational environmentof the candidate.There is little point in trying to improve auditory capacity with a cochlear implant if the patient will not have the opportunityto use that capacity for the development of spoken languageskills in the classroom. For example, if apatient is part of aculturewhere

86

Chapter 15

communication is by signing rather than speech, he/she will be less likely to benefit from implantation than a child living in anoral environment.Thesupport of teachers of the deafis an essential ingredient fora successful paediatric implant.

Many deaf adults do not consider themselves deprived or handicapped as aresult of their deafness. Indeed, they often believe that they are a subgroup of a population who simply use a different, albeit unspoken, language. It would be wrong to assume that those belonging to this group must be offered cochlear implantation. This also has implications fordeaf children of deaf parents, as the parents may assume that their children will wish to grow up within the deaf community. tiva

Rehabilitation following cochlear implantation is a long and arduous process, requiring many visits to the implantcentre over a long period.It is importantthat implant candidates or the parents of child candidates understand the degree of commitment required to gain maximum benefit from an implant.

Cochlear implantation is an expensive treatment modality. Currently the cost is in the region of 650 000 over a 10-year period. Of this, about half is expended in the first year. Funds must be available to cover the cost of long-termfollow-up, replacement of implants in the event of device failure and possible upgrading of devices in the future.

Potentialimplantcandidatesmust be fit for surgery under general anaesthesia and also fit enough to attend the implant centre as an out-patient for rehabilitation.

Audiometric testing should be carried out to check the hearing thresholds of implant candidates. These include pure-tone audiometry (PTA), to determine both aided and unaided thresholds, speech discrimination tests and tests to exclude non-organic hearing loss if indicated. Since young children are oftendifficult to test, it may be appropriate to perform several audiograms by paediat-

ric audiologists at repeated intervals to obtain absolutely reliable thresholds. Auditory brain-stem responses may supplementbehavioural testing but do not replace it. Otoacoustic emissions are also valuable in the assessment. It is important to check that hearing-aids are optimally fitted and thatthe patient wearsthem and that they are performing to manufacturer’s specifications. High-definition CT scans set on bone windows in axial and coronal planes withcontiguous 1mm cuts should be obtained. These will demonstrate the anatomy of the cochlea and adjacent structures and can be used to determine if there are any anomalies of the middle ear or cochlea. Of particular importance are the position of the facial nerve, the presence or absence of osteoneogenesis of the cochlea, the thickness of the cranial vault and the state of the internal auditory canal (IAC). CerebralCT scans (on soft-tissue settings) should be used to evaluate the central auditory pathways.MRI scans may be needed in additiontoCTin selected patients. MRI is complementary to CT as it can better demonstrate the central auditory pathwaysand labyrinthine fluids. For children, evaluation of theeducational and communicationalmode of the child should be determined prior to implantation.

1 The operation is performed under general anaesthesia with endotracheal intubation. 2 Broad-spectrum antibiotics (e.g. acephalosporin) are given on induction of anaesthesia. This is continued intravenouslyfor 24h. After this theantibioticsare given orally for a further 5-7 days postoperatively. 3 The surgical field is prepared by shaving two-thirds of the scalp on the side to be operated on. Thescalp and ear are cleaned with a suitable antisepticand the area is draped with sterile towels. 4 Several incisions can be used. These include an inverted-U incision, a C-shaped incision or an extended endaural incision (Fig. 15.1). It is important that there should be a marginof at least 2 cm between the intended position of the implant and the edge of the wound so that the implant will not lie under the suture line. A scalp flap is raised to give exposure of the squamous and mastoid portions of the temporal bone. 5 A limited cortical mastoidectomy is carried out to expose the mastoid antrum, lateral semicircular canal and short process of the incus. It is not necessary to saucerise the edges of the cavity, as is done in mastoidectomy for chronic eardisease. Holes are drilled

Cochlear Implantation

Fig. 15.1 (a) Theinverted-Uincision. incision. (c) The C-incision.

(b)Theextendedendaural

Fig. 15.2 Theposteriortympanotomy. Theroundwindow has been exposed via the facial recess. The short process o f the incus provides a landmark for the position o f the facial nerve which marks the posterior limit o f the dissection.

inthecortical bone adjacent to the cavity to allow placement of ties to anchor the implantdevice at the end of the procedure. 6 A well is fashioned posterior to the cavity to receive the implant device. Use of a template is helpful at this stage. A groove is then drilled to connect the well with the mastoid cavity in order to allow the electrode lead wire to be placed. 7 A posterior tympanotomy allows access to the middle ear (Fig. 15.2). Themainlandmark is theshort process of the incus. The bone should be drilled in a line passing inferiorly from the short process of the incus towardstheanteriorpart of the digastric ridge. The

87

facial nerve should lie about 2mm posterior to this line, but care mustbe taken in case its course is aberrant. The facial recess can be entered just inferior to the fossa incudis. Theposteriortympanotomy is then enlarged to allowgoodexposure of theround-window niche. Neuromonitoring of the facial nerve is helpful. 8 A cochleostomy must be made for insertion of the cochlear implant electrode array. Two approaches are available: via the round window or via a fenestration anteroinferior to the round window(Fig. 15.3). If there has been osteoneogenesis of the cochlea, it may be necessary to drill further into the basal turn of the cochlea in order to enter the patent scala tympani. 9 The electrode array is inserted into thescala tympani via the posterior tympanotomy (Fig. 15.4). This can be facilitated by using aclaw to gently advance the elec-

Fig. 15.3 The ant~o-inferiorfenestration.

Fig. 15.4 Bone removalwitha

fine hook.

88

Chapter IS secure itwithinthe well in order to prevent device movement postoperatively (Fig. 15.5). 10 Closure should be in layers after meticulous haemostasis. Once the device is in place, it is extremely important thatonly bipolar diathermyis used. A drainis usually not required.Amastoid pressure dressing is applied for 24 h. Figure 15.6 shows a diagram of the components of theimplant and their relationship to each other when worn by the patient. 11 Electrophysiological testing may be carried out at the end of the procedure to determine electrical thresholds and to estimate discomfort levels, i.e. to check the electrical dynamic range.

Postoperative management

Fig. 15.5 The implant secured in place. Non-absorbable sutures are shown holding the implant package in place. Dacron ties secure the electrode wire in place.

trode array. Gentle rotation of the implant may facilitate placement. It is important not to continue advancement after resistance is felt, or damage will occur to either the electrode or the osseous spiral lamina. After satisfactory placement of the device, ties can be used to

The dressings are removed after 24-48 hand the wound inspected for evidence of infection or haematoma. Antibiotics are continued orally for 7-10 days. A Stenver’sview radiograph is obtained on the day after surgery to check that the electrode array is correctly positioned without kinking, and has not been inserted intothe Eustachian tube or into a hypotympanic air cell.

Complications 1 Haemorrhage: may be primary or secondary. 2 Haematoma under the flap: may be left if only small but may need drainage if large.

Fig. 15.6 A diagram to show the constituents of the cochlear implant system. Sound is picked up by the directional microphone. It is then carried to the speech processor, where the sound information is converted into electrical signals before being relayed to the implanted device via the externally worn transmitter by induction coupling. The electrode array then selectively stimulates the remaining auditory-nerve fibres.

Cochlear Implantation 3 Flap necrosis: may be associated with excessive thinning of the flap during surgery orpoor soft-tissue technique. 4 Perforation of thetympanicmembrane (TM):can occur during fashioning of the posterior tympanotomy, particularly if the posterior meatal wall is excessively thinned. 5 Facial-nerve injury: this may result from direct injury to the nerve during development of theposterior tympanotomy, or indirectly if the shaft of the burr impinges on the nerve and generates excessive heat during drilling, 6 Perilymph fistula: this usually settles spontaneously and rarely requires further plugging of the cochleostomy. 7 Malposition of the electrode: the electrode may be inadvertently inserted intotheEustachiantube or intoahypotympanicair cell. Re-exploration rnay be required. 8 Woundbreakdown: this can occur asa result of faulty technique, e.g. if the soft-tissue flap is handled too roughly, if the flap is thinned excessively or if diathermy is used indiscriminately. Wound breakdown can lead to device extrusion. 9 Infection: this can be a serious problemand may

8

"

89

~

require implant removal. Problems can be avoided by paying careful attention to sterile technique and avoiding excessive diathermy to the soft-tissue flap. If infection does develop, it should be treated aggressively with parenteral antibiotics. 10 Implant failure: may be partial (in which case there may be aberrant sensation) or complete. The latter will require device replacement, which can usually be achieved without detriment in function. 11 Meningitis: after cochlear implantation there is a conduit between the middle ear and the labyrinth,which couldpotentiallytransmit infection to the meninges. Otitis media in children should be treated with appropriate oral antibioticsand does not require admission to hospital if it remains uncomplicated. 12 Pevice extrusion: rnay occur if the incision has been poorly planned so that it lies too close to the position of the implant.

Further reading Clark GM,Tong YC & Patrick JF (1990) CochlearProstheses. Edinburgh, Churchill Livingstone. Tyler RS (ed.) (1993) CochlearImplants. San Diego, CA, Singular Publishing Group,

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Otoneurosurgery and Skull Base Surgery

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roaches to I Auditory Canal lopontine R O B E R T J.S. BRIGGS Original illustrations by John Li Introduction

Acoustic neuroma

The surgical approach to theinternalauditorycanal (IAC) is most often performed for removal of acoustic neuromas (vestibular schwannomas) and usually involvesaccess to the cerebellopontine angle (CPA).A variety of approaches to the IAC have been developed, of which three are most commonly utilised for acoustic neuroma removal: retrosigmoid, translabyrinthine and middle cranial fossa (Fig. 16.1). Each approachhas distinct advantages and disadvantages, which are outlined below. There is potentialfor considerable morbidity and mortalityfromacousticneuroma removal. Preferably patients should be managed by combined neurotological and neurosurgical teamswith experience in all three surgical approaches.Thereby,themostsuitable approach may be selected for the individual patient, depending on tumour size and hearing level (Jackler & Pitts, 1992).

Contraindications to surgical removal

Tumour observation with repeated imaging is recommended for: 1 an elderly patient with small tumour; 2 a medically unfit patient; 3 a tumour in an only hearing ear; provided that: (a) there are no major neurological symptoms or elevated intracranial pressure; (b) there is no evidence of tumourgrowthon repeated imaging; (c) the patient is not disabled by vertigo.

Indications 1 Acoustic neuroma -total surgical removal. 2 Vestibular-nerve section: (a) retrosigmoid,retrolabyrinthine or middle-fossa approach for hearing preservation; (b) translabyrinthine if residual hearing is not worth preserving. 3 Other CPA tumours -meningiomas, facial-nerve neuromas, etc. 4 Petrous-apes lesions -cholesteatomas and cholesterol granulomas may require approach to the IAC and petrous apex for removal or drainage. 5 Facial nerve decompression or repair.

\Sigmoid sinus

Fig. 16.1 Three major approaches to the internal auditory canal.

93

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Chapter 16

Preoperative management

Audiological assessment The following may have been part of the diagnostic investigation; otherwise they should be obtained prior to surgery (Josey et al., 1988). 1 Pure-tone audiometric (PTA) thresholds. 2 Speech -reception thresholds and discrimination score. 3 Auditory brain-stem response (ABR)-may help to predict degree of cochlear-nerve involvement and potential for hearing preservation. 4 Electronystagmography (ENG)-demonstrates degree of residual vestibular function and predicts postoperative vestibular disturbance. 5 Electroneuronography (ENOG)-if significantly abnormal suggests possible facial nerve neuroma. Imaging 1 MRI with intravenous gadolinium enhancement-the most sensitive and highest-resolution technique -is preferable in all cases. 2 CT: (a) withcontrast infusion will demonstratelarger tumours; (b) smaller tumours may requireair-contrastsubarachnoid injection; (c) provides superior bone definition to MRI; may assist in assessing if the posterior semicircular canal position allows access to the lateral IAC for retrosigmoid hearing preservation.

2 Intravenousmannitol and steroidsare given routinely, together with antibiotics if a long procedure is anticipated. Relevant anatomy

The IAC is situated in the petrous portion of the temporal bone. The vestibular and cochlear divisions of cranial nerve VI11 pass fromthemembranouslabyrinth through the IAC to the CPA and brain stem. The facial nerve and nervus intermedius pass from the brain stem through the CPA and IAC to the Fallopian canal. The IACis lined by duraand also transmitstheinternal auditory artery, usually a branch of the anterior inferior cerebellar artery (AICA). Not uncommonly, a loop of theanterior inferior cerebellar artery itself may lie within the porus of the IAC. The arrangement of the nerves within the lateral IAC is shown in Fig. 16.2. The porus or medial opening of the IAC is situated on the posterior surface of the petrous pyramid, approximately mid-way between apex and base. Internal auditory canal relations

1 Anterior -petrous apex and cochlea. 2 Posterior -common crus of posterior and superior semicircular canals and vestibular aqueduct. 3 Inferior -cochlearaqueduct, jugular foramenwith cranial nerves IX, X, XI and jugular bulb. 4 Lateral -to the IAC fundus -cochlea and vestibule of

Autologous blood Transfusion is rarely necessary; however, autologous blooddonation in advance is preferable. Autologous fibrin glue may be helpful to seal the IAC during closure. Intraoperative monitoring

1 Electromyographic (EMG) facial nerve monitoring is essential to optimise facial nerve preservation in tumours greater than 1.5cm (Kwartler et al., 1991). 2 Intraoperative electric-response audiometry -by ABR or direct nerve VI11 monitoring -has notyet beenshown to improve rates of hearing preservation.

1Cochlearnerve

\ Inferior vestibular nerve

Anaesthesia

1 A non-muscle-relaxant technique with intra-arterial monitoring of blood-pressure and heart rate.

Fig. 16.2 Arrangement of nerves within the lateral internal auditory canal (right side).

Approaches to theInternalAuditoryCanal labyrinth, middle earand externalauditorycanal (EAC). Medially the IAC opensintothe CPA. The CPAis bounded by the cerebellum and flocculus posteriorly, the ponsand medulla medially and the petrous temporal bone anterolaterally, the tentorium superiorly and the basal cisterns and foramen magnum inferiorly. Cranial nerves VI1 and VI11 join the brain stem at the pontomedullary sulcus, with the trigeminal nerve anterosuperior, the abducens nerve anterior and cranial nerves IX, X and XI inferior. Other brain-stem landmarks are theflocculus, the foramen of Luschka and the choroid plexus; the lateral recess of the fourth ventricle is posteroinferior to the nerve VI11 complex.

The retrosigmoid-transmeatal approach may be used for removal of small or large acoustic neuromas (Sammi et al., 1985).Hearing preservation is possible in suitable cases. A modification of the suboccipital craniotomy, a smaller and more lateral bone removal, still allows a wide view of the posterior fossa. The posterior bony lip of the IAC is removed to expose the contents of the canal. Unfortunately, the lateral end of the IAC cannot be directly visualised without removing portions of the inner ear.

Preparation

Position Either supine with head rotated away orpark-bench (or even three-quartersproneposition).Thepark-bench position is preferable as it allows easier access for the transmeatal (lateral) dissection without excessive head rotation. Also the cerebellum tends to fall away slightly moreafter CSFis released. The neurosurgical headholder may be used to secure the head. Procedure

Incision A curved (S-shaped) incision is made 3 4 c m behind the postauricular sulcus (Fig. 16.3). If mastoidectomy is performed, the superior limb is carried further anteriorly. Inferiorly the incision extends into the nuchal muscles to expose the subocciput. mastoidectomy A is a useful addition to the retrosigmoid approach. Decompression andforward retraction of the sigmoid sinus is possible. The posterior semicircular canalcan be skeletonised, aiding subsequent bone removal fromthe IAC. Dura behind the posterior semicircular canal can be decompressed and a small incision made to release cerebrospinal fluid (CSF).

Acoustic-neuroma indications

The retrosigmoid approach is ideally suited for tumours smaller than 2cm: 1 medially situated within the CPA without extension to the fundus of the IAC as demonstrated on MRI; 2 with good hearing-PTA less than 30 dB and speech discrimination greater than '70% . Advantages

1 Any size tumour. 2 Potential hearing preservation. 3 Minimal temporal-bone dissection for exposure. 4 Early visualisation of CPA vessels. Disadvantages 1 Cerebellar retractionparticularly for large tumours. 2 Delayed identification of distal facial nerve. 3 Blind dissection of lateral IAC: potential for incomplete tumour removal. 4 Prolonged occipital headache.

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Fig. 16.3 Incision for retrosigrnoid approach.

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Chapter I 6

Craniotomy A retrosigmoid bone flap is removed, using a cutting burr to 'blue-line' dura or a craniotome. Chronicoccipital headache is perhaps secondary to muscle attachment to duri andmay be avoided by replacing the bone flap. The craniotomy measures approximately 3 -5 cm, with the transverse sinus asthesuperiorborder and the sigmoid sinus as the anterior border. A semilunar dural incision is made behind the sigmoid sinus to createa posteriorly based dural flap, which helps protectthe cerebellum. Anteriorly suturesare placed in the dural edge behind the sinus to retract it forward (Fig. 16.4). The operating microscope isused for all intradural work.Thesubarachnoid space is openedandthe cisterna lateralis entered inferiorly. Usually the cerebellum will fall way with release of spinal fluid, exposing theposteriortemporal bone and the tumour. A selfretaining retractor with a wide brain spatula may be used, to protect rather than retract thecerebellum. Dura of the posterior petrous face overlying the course of the IAC is elevated as a laterally based flap. Alternatively it may be excised after bipolar haemostasis. Saline-soaked pieces of Gelfoam are placed over exposed cerebellum and on either side of the tumour to minimise spread of bone dust. Removal of theposterior wall of the IACis accomplished using cutting and diamond burrs, after pal-

pation of the canal direction with a right-angled hook. For larger tumours, debulking of the CPA component of the tumour may be necessary prior to bone removal. The IAC is skeletonised 180" of its circumference with dissection beginning medially (Fig. 16.5). Inferiorly, care must be taken not to enter the jugular bulb. Bone removal proceeds until the lateral extent of the tumour is seenwithin theIAC or until the transverse crest can be palpatedwith an angled instrument such asa lancet knife. Further bone removal will openlabyrinthine structures with resultant hearing loss.Because of the oblique view, it is difficult to visualise a 'blue line' of posterior semicircular canal or vestibule before the labyrinth is entered.

Tumour removal The dura of the IAC is opened longitudinally to expose the tumour and nerves. Tumour removal is then performed, with initial debulking and then dissection of the capsule froma medial to lateral direction. Small tumours may not require debulking; for large tumours an ultrasonic aspirator or rotary suction dissector is useful. Dissection is in the plain between the tumour capsule and the overlying arachnoid. Allvessels are separated from the tumour and preserved. Bipolar coagulation is used to control those that directly penetratetumour. Tumour is dissected away from neural structures rather than retracting nerves or brain stem from the tumour.

Fig. 16.4 Retrolabyrinthine exposure and retrosigrnoid dural incision.

Approaches to the Internal Auditory Canal

97

Fig. 16.5 Tumour exposure and internal auditory canal bone removal.

Fig. 16.6 Retrosigmoid tumour removal complete.

Often tumour is found to be adherent to the facial and cochlear nerves at the level of the porus. Thefacial nerve is then identified laterally at the origin of the facial canal, and tumour is separated from the posterior surface of the facial and cochlear nerves within the IAC.

Medial and lateral dissection of thetumour is then possible, with positive facial-nerve identification. Sharp dissection at the level of the porus may be necessary to remove final remnants of tumour (Fig. 16.6).

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Chapter 1 6

Closure

After tumour removal is complete and absolute haemostasis is secured, air cells exposed around theIAC are occluded with bone wax andthe IAC defect is closed with a piece of abdominal fat. The dura is closed in a watertightfashionandthe bone flap replaced. If a mastoidectomy wasperformed,the cavity is packed withabdominalfat;otherwiseany exposed mastoid cells are occluded with bone wax. The wound is closed in layers without a drain and a pressure dressing is applied. T~ans~abyrinthine approach

The translabyrinthine approach is also suitable for removal of acoustic neuromas of any size (House, 1979; approach is also used Briggs et al., 1994). This for vestibulocochlear nerve section in patientswith disabling vertigo when no useful hearing remains, for facial nerve decompression and repair following temporal-bonefractures, orfor removal of facial nerve neuromas when hearing is lost. Acoustic-neuroma indications

1 Any size tumour with poor hearing. 2 Tumours >2cm with good hearing (when shown to extend to the lateral IAC on MRI). Advantages

1 Any size tumour. 2 Minimal cerebellar retraction. 3 Anatomical distal facial nerve identification. 4 Total tumour removal from lateral IAC. S Potential for direct facial nerve repair (rerouting and primary anastomosis or interposition grafting) if necessary. 6 Auditory brain-stem implant (placement in lateral recess of fourth ventricle is possible forpatientswith bilateral acoustic neuromas). Disadvantages

1 Total hearing loss. 2 Delayed access to CPA vessels. 3 Large dural defect.

4 Longer bone-dissection time.

Fig. 16.7 Incision for translabyrinthine approach.

Preparation

Position Supine with thehead turned to theopposite side without fixation. The head is shaved 4 cm above and 6 cm behind the ear. Procedure

Incision A curved postauricular incision 3-4 cm behind the postauricular sulcus aroundto themastoidtip (Fig. 16.7). Sufficient posterior accessis necessary to allow decompression of the sigmoid sinus. Initial incision is to the temporalis fascia, and then superiorly a flap is elevated to the linea temporalis. Incision is thenmade throughthe fascia and periosteum alongthe linea temporalis to the sinodural angle and then inferiorly to the mastoid tip. Periosteal elevation then exposes the underlying mastoid cortex. Careis taken not toenter the external auditory canal (EAC). The ear is reflected forwards by self-retaining retractors. Posteriorly the occipital bone is exposed behind the sigmoid sinus and superiorly the squamous temporal bone is exposed beneath the temporalis muscle.

Approaches to the Internal Auditory Canal Mastoidectomy A complete simple mastoidectomy is performedwith total removal of mastoid cortex. The middle-fossa plate is exposed superiorly and the sigmoid sinus posteriorly. For larger tumours, bone removal is carried 2cm or more behind the sigmoid sinus and the dura is decompressed. Early use of the operating microscope allows more accurate bone removal and control of emissary veins. A thin shell of bone, 'Bill's island', is left over the sigmoid sinus to protect it during subsequent drilling and compression. The mastoid antrum is opened and the incus and lateral semicircular canal are identified. All mastoid air cells are removed and the digastric ridge is exposed inferiorly. The facial nerve may be skeletonised in its descending segment at this stage or subsequent to labyrinthectomy (Fig. 16.8).

Labyrinthectomy The next step is removal of the bony labyrinth. Initial bone removal is farthest from the facial nerve in the sinodural angle along the superior petrosal sinus. The lateral and posterior semicircular canals are progressively removed until the common crus of the posterior and superior semicircular canal is identified. The superior semicircular canal is then followed to its ampulla anteriorly. The second genu of the facial nerve is identified inferior to the lateral semicircular canal and the nerve is skeletonised from its tympanic segment to the stylomastoid foramen. Bone is removed from the medial

Fig. 16.8 Complete mastoidectomy, sigmoid sinus and dura decompressed.

99

aspect of the genu to open the vestibule widely (Fig. 16.9). This is the key to exposure of the lateral IAC. The cribriform area of the superior vestibular nerve entering the vestibule should be visualised.

Internal-duditory-canal dissection The final stage of bone removal is dissection of the IAC. Posterior fossa dura medial to the sigmoid sinus is entirely skeletonised and decompressed. Bone removal commences alongthesuperiorpetrosalsinus and is carried forward in all directions toward the IAC. The dome of the jugular bulb is identified inferiorly, medial to the retrofacial air-cell tract. The vestibular aqueduct and medial endolymphatic sac are removed as theIAC is approached. The ampulla of the superior semicircular canal provides a landmark for the lateral end of the superior IAC and is preserved until medial bone removal is complete. The subarcuate artery penetrating thebony arch of the superior semicircular canal provides a guide to thesuperiorborder of the IAC. Medially, greater bone removal is required to expose the porusof the IAC. It is necessary to remove bone 270" around the IAC. Dissection is completed inferiorly first. A suitable-size cutting or diamond burr is selected to fit between the jugular bulb and the inferior border of the IAC. Dissection is carried forward and medially until the cochlear aqueduct is identified. This forms the inferior limit of dissection to avoid injury to cranial nerve IX in the neuralcompartment of the jugular foramen.Further bone may be safely removed anteriorly, superior to the cochlear aqueduct. After complete skeletonisation of the

IOO

Chapter 16

Fig. 16.9 Labyrinthectomy completed.

inferior border of the IAC, dissection is carried superiorly and anteriorly between the middle fossa dura and the superior border of the IAC, following the superior petrosal sinus anteriorly. A diamond burr shouldbe used with rotation away from theIAC to minimise risk of facial-nerve injury. Facial-nerve EMG monitoring facilitates accurate identification and avoids injury to the nerve, It is possible to mobilise and remove the rim of bone at the porus as a single segment and reduce the amount of drilling necessary. The lateral endof the IAC is dissected last. The singular nerve is first identified and then bone is removed to expose the inferior vestibular nerve. The transverse crest is identified and then the superior aspect of the IAC is dissected. The superior vestibular nerve is identified and separatedfromthelongitudinal crest (Bill’s bar; Fig. 16.10). This is the posterior border of the facial canal and a landmark for the facial nerve. The labyrinthine portion of the facial canal may be decompressed superiorly, further identifying the facial nerve as it exits the IAC. After removing any remaining eggshell-thin bone from the posterior and middle fossa dura, the defect is copiously irrigated to remove remaining bone dust before the intradural procedure.

Dural incision A longitudinal incision is made in the posterior fossa dura over the midpoint of the IAC. For larger tumours, the incision extends back to the sigmoid sinus. Care is taken in elevating the dura so as to avoid underlying

vessels. The duralflaps are then retractedsuperiorly and inferiorly by separating dura around the porus from the tumour. Superiorly the facial nerve must be avoided. Inferiorly the arachnoid is opened to allow CSF drainage from the basal cisterns and to decompress the posterior fossa.

Tumour removal Tumour removal is performed as described above. Tumours larger than 1cm usually require initial debulking to allow safe removal. Provided no nerve bundles lie on the posterior surface, the capsule is incised and debulking is commenced. As the tumour is gutted, the plane between tumour capsule and surrounding neural and vascular structures is developed, initially posteroinferiorly and then medially. Superiorly the petrosal vein will be found. It may be adherent to large tumours andmust be carefully separated. Venous bleeding may be controlled by bipolar coagulation; occasionally clipping of the petrosal vein or even the superior petrosal sinus may be necessary. Dissection of the facial nerve is facilitated by identification both medial and lateral to the tumour. Dural adhesions to the tumour at the porus tend to involve the facial nerve and can make dissection very difficult. Once the tumour is separated from the facial nerve to thebrain stem, it may be furtherdebulked before the final adhesions arefreed. Cranial nerve VI11 is divided medially and the tumour remnantremoved (Fig. 16.11).

Approaches to the Internal Auditory Canal

IOI

Fig. 16.10 Bone removal and internal auditory canal dissection complete.

Fig. 16.11 Translabyrinthine tumour removal complete.

Haemostasis

and closure

Aftertotaltumourremoval,the gated with Ringer’ssolutionand

removed. Any bleeding points are controlled by bipolar cauteryandabsolutehaemostasis is obtained.Dural CPA is profuselyirriedges arethenapproximated withinterruptedsutures. any bloodclotsareAbdominalfat is thenplacedinlongitudinalstrips to

102

Chapter 16

occlude the residual dural defect. A piece of muscle is used to obliterate the additus and the remainder of the mastoid cavity is packed with fat. The incision is closed in layers without drainage and a mastoidpressure dressing is applied. Middle-cranial-fossa approach

The middle-cranial-fossa approach to the IAC was refined byWilliam F. House (1961).Although perhaps the most challenging of temporal-bone dissections, it is the only approach which allows access to the lateral IAC without breeching the inner ear. The approach is ideally suited for small acoustic neuromas which extend to the lateral end of the IAC. Otherindicationsfortheapproach are: (i) decompression or repair of the labyrinthine and upper tympanic segment of the facial nerve, particularly following temporal-bone fractures where hearing remains, or for tumours involving the facial nerve; (ii) selective vestibular-nerve section; and (iii)decompression of the IAC for bilateral acoustic neuromas. Acoustic-neuroma indications

Procedure

Incision A curved incision is made with a vertical inferior limb placed just anterior to the base of the helix to create a posteriorly based skin flap (Fig. 16.12). The incision is kept behind the hairline. Branches of the superficial temporal artery are ligated. The skin flap is elevated at the level of the temporalis fascia. The temporalis muscle is separated from bone to the temporalline and elevated as an anteroinferiorly based flap, preserving its nerve and blood supply. Self-retaining retractors are used to secure the flaps.

Craniotomy Using a cutting burr or craniotome, a craniotomy approximately 5cm square is madeinthesquamous portion of the temporal bone, with its base at the middle-fossa floor. Care must be taken not to lacerate the dura. Bone bleeders are controlled with bone wax and bipolar cauteryis used to controlbranches of the middle meningeal artery. The bone flap is set aside in normal saline for subsequent replacement.

Intracanalicular tumours, extending to the lateral IAC, with up to0.5 cm of CPA extension, provided hearing is of serviceable level. Advantages 1 2 3 4

Potential hearing preservation. Exposure of lateral IAC. Extradural brain retraction. Positive identification of facial nerve.

Disadvantages 1 2 3 4 5

Small tumours only. Temporal-lobe retraction. Technically difficult temporal-bone dissection. Poor access to CPA vessels. Dissection past the facial nerve.

Preparation

Position Supine withtheheadturned andthe operatedear upmost without external fixation. The head is shaved approximately 1Ocm above the pinna.

Fig. 16.12 Incision for middle-cranial-fossa approach.

Approaches to the Internal A ~ d ~ t Canal or~ Dural elevation Initially thedura is separatedfrombothlateral and inferior borders of thecraniotomy. Inferiorly further bone may be removed to the level of the middle-fossa floor. If mastoid air cells are opened posteriorly, these are occluded with bone wax. Using the operating microscope, dura is elevated from the tegmen of the temporal bone, from posterior to anterior. This avoids injury to the facial nerve if the geniculate ganglion is exposed. The bony covering of the geniculate ganglion is variable, with dehiscence in approximately 5%. The HouseUrban retractor is secured to the craniotomy margins and the blade inserted and advanced as dural elevation proceeds. The petrous ridge is identified posteriorly, taking care not to injure the superior petrosal sinus. The arcuate eminence is identified, anteriorto which thegreater superficial petrosal nerve is found. Further anterior, the middle meningeal artery is identified at theforamen spinosum and this markstheanterior limit of dural elevation. Medially, dura is elevated along theline of the petrous ridge to expose the region of the MC, the line of which bisects the angle between the superior semicircular canal (arcuate eminence) and the greater superficial petrosal nerve (Fig. 16.13). During dural elevation there is often considerable bleeding. Small dural vessels are

Fig. 16.13 Middle-fossa craniotomy and outline of intratemporal structures.

103

controlled by bipolarcautery. Venous bleeding from bone is controlled by bone wax, andvenous sinus bleeding, e.g. aroundforamen spinosum, is controlled by surgicell packing.

Dissection of the internal auditory canal William House originally described identification of the IAC by bone removal alongthegreater superficial petrosal nerve until the geniculate ganglion was ident,-ified. Then careful medial dissection followed the facial nerve within its labyrinthine segment to the IAC. Another technique is to remove bone over the arcuate eminence until the superior semicircular canal is identified by its blue line. The IAC isthen identified by medial dissection at anangle of 45 -60" with the superior semicircular canal. Both of these methods requiremeticulous technique with little margin for error, as the ampullated end of the superior semicircular canal and the cochlea both lie within millimetres of the facial nerve at the labyrinthine segment. An alternative techniqueis medial identification of the IAC beneath thepetrous ridge, where bothsuperior semicircular canal and cochlea are at greatest distance (Brackmann et al., 1994). Theline of the IAC is identifiedby bissecting thegreater superficial petrosal and arcuate eminence. Bone removal is commenced using a

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large diamond burr and continuous-suction irrigation. The key to successful acoustic-neuroma removal via the middle-fossa approach is wide bone removal both anteriorly into the petrous apex, medial to the otic capsule of the cochlea, and posteriorly to the semicircular canal. Using decreasing sizes of diamond burr, the posterior fossa and IAC duraare blue-lined with bone removal 270" around the porus. After medial exposure of thecanal, bone is gradually removed inalateral direction. Posteriorly the superior semicircular canal is identified and skeletonised. Towards the lateral end of the IAC, care is taken not to remove bone anterior tothe IAC, as this risks entering the cochlea. The exact extent of the IAC is determined by extradural palpation with a small hook or elevator. As lateral dissection proceeds, the labyrinthine portion of the Fallopian canal is identified and the facial nerve decompressed to the geniculate ganglion. This allows accurate identification of Bill's bar, which marksthelateralextent of the IAC (Fig. 16.14). EMG facial-nerve monitoring greatly facilitates non-traumatic bone dissection along the course of the facial nerve. If difficulty is encountered in identifying the IAC or superior semicircular canal,thena safe method is to remove bone over the tegmen tympani until the middle ear is entered. This allows accurate identification of the superior semicircular canal at its junction with the an-

terior lateral semicircular canal and facilitates the medial dissection. The tegmen bony defect should subse-. quently be repaired with a piece of split calvarial bone from the bone flap. Dural incision

Thedura is initially incised posteriorly between the porus acousticus and the superior petrosal sinus. CSF is released and then a longitudinal dural incision is made along the posteriorIAC. Care is taken where the durais adherent to tumour andnerves at the porus. The durais carefully elevated and reflected anteriorly, exposing the facial nerve overlying thetumour.The vertical crest (Bill's bar) allows positive identification of the facial nerve at the lateral IAC (Fig. 16.15). Tumour removal

Successful tumour removal with facial nerve preservation is accomplished by initial separation of the facial nerve fromthetumour, using bothsharpand blunt dissection, facilitated by facial nerve monitoring. Unless the tumour is very small, it is debulked prior to further removal. Initial debulking allows subsequent manipulation of the tumour within the IAC without stretching the facial or cochlear nerves. Tumour removal is again

Fig. 16.14 Internal auditory canal bone removal complete and dural incision.

Fig. 16.15 Exposure of tumour within the internal auditory canal.

performed by medial-to-lateral dissection, thus avoiding tractionon the fragile nerve fibres enteringthe cochlea (Fig. 16.1 6). During medial dissection of the tumour,caremust be taken to identify and preserve the anterior inferior cerebellar artery, which may loop between the facial and cochleovestibular nerves at the porus.

2 Intensive-care-unit observation, at least 24 h.

Closure

1 Intracranial haematoma-manifested by signs of increased intracranial pressure -requires immediate evacuation. 2 Cerebellar or brain-stem infarct-may result from injury to the proximal AICA. 3 Cerebellar haematoma or swelling-may result from excessive cerebellar retraction. 4 Facial nerve paralysis- temporary or permanent. Requires intensive eye-care to avoid ophthalmic complications. 5 CSF leak-rhinorrhoea orwound-may settle with pressure dressing and lumbar drainage or require surgical closure. Meningitis: (a) aseptic-secondary to blood, fat and bone dust in subarachnoid space; (b)septic-requires appropriate antibiotics. Injury to other cranial nerves.

After total tumourremoval and absolute haemostasis, it is sometimes possible to reapproximate the dural flap with a single suture. The bony IAC defect is then occluded gently with abdominal fat. Any air cells opened on the temporal-bone surface are occluded with bone wax. The blade of the middle-fossa retractor is removed and thedura allowed to re-expand. After epidural haemostasis is secure, a Penrose drain is placed in the extradural space and the bone flap replaced. A single suture to the superior bone flap is useful to prevent the occasional internal subluxation of the bone flap. The temporalis muscle is replaced and sutured. The incision is repaired in layers and a sterile pressure dressing is applied. The drain is removed after 24h. Postoperative care 1 Similar for each approach.

3 Steroids continued for large tumours.

4 Pressure dressing in place 4 days. 5 Patient instructed not to lift or strain during the early postoperative period. licati

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Fig. 16.16 Middle-cranial-fossatumour removal complete.

Refere BrackmannDE,House JR & Hitselberger WE (1994) Technichal modifications to the middle cranial fossa approach in removal of acoustic neuromas. AJO. 15, 614-619. Briggs RJS,LuxfordWM, Atkins J S & Hitselberger WE(1994) Translabyrinthineremoval of large ( 2 4cm)acoustic neuromas. Neurosurgery. 34, 785-792. House WF (1961) Surgical exposureo f the internal auditory canal and its contentsthroughthe middle cranialfossa. Laryngoscope 71, 1363, House WF(1979) Translabyrinthineapproach.In:House WF & Leutje C M (eds) Acoustic Tumors, Vol.2.Baltimore, University Park Press, pp. 43-87.

Jackler R K & Pitts LH(1992) Selection of surgicalapproach to acoustic neuroma. Otolaryngol. Clin. North Am. 25(2), 361-87. Josey AF, Glasscock M E & Jackson CG (1988)Preservation of hearing in acoustictumor surgery: audiologicindicators. Ann. Otol. Rhinol. Laryngol. 97, 626-30. Kwartler JA, Luxford W M , Atkins J & Shelton C (1991) Facial nerve monitoring in acoustictumor surgery. Otolaryngol.HeadNeck Surg. 104, 814-17. Sammi M, Turel K E & Penkert G (1985) Management o f seventh and eighth nerve involvement by cerebellopontine angle tumours. Clin. Neurosurg. 32, 242-72.

. CROXSON

~ntroduction Surgery of the facial nerve requires operative access to the cerebellopontine angle (CPA),theintratemporal part of the facial nerve and the extratemporal portionof the facial nerve in the parotid gland. It has onlybeen with the recent advances in operative surgery of the middle cranial fossa and CPA that routine approaches to the intracranial and labyrinthine portions of the facial nerve have been undertaken. Similarly, the development of the operatingmicroscope and high-speed drill technology has enabled all parts of the intratemporal portion of the facial nerve to be safely accessed.

indications There are three general indications for operating on the facial nerve. Loss of proximal origi facial nerve

The most common exampleof proximal loss of continuity occurs during acoustic neuroma removal when the facial nerve is disrupted at or close to its exit from the brain stem. In this situation, nerve substitution is required,themostcommonprocedures being facialhypoglossal anastomosis or cross-facial anastomosis. Loss of nerve continui~y

The facial nerve can be disrupted in the CPA, its intratemporal course or its extratemporal course throughtheparotid.Common causes of this include traumatic fracture of the petrous temporal bone, sharp

and blunt injury to the parotid and iatrogenic injury of the nerve at the time of acoustic neuroma surgery, temporal bone surgery or parotidectomy. scular

Theperipheralneuromuscularend-organcan be lost eitherasa result of surgical ablation,inthe case of radicalparotidectomy, or throughatrophy associated with prolonged facial nerve denervation. The interval from denervation untilirretrievable neuromuscular endplate deterioration is controversial; however, many authors believe a period of approximately 18 months tobe the limit (Conley, 1986; May, 198613).In this situation, a new neuromuscular system needs to be introduced. Temporalis transfer is a reliable, local one-step method of creatingdynamicreanimation to the face where neuromuscular end-plate activity is lost. More complex methods involving free tissue grafting with neural, vascular and muscular reattachment have the potential for excellent results, but require multiple stages and ultimately there is increased risk of failure (Harrison, 1985).

re

e

Preoperative assessment aims to diagnose the cause of the facial-nerve paralysis, locate the site of the lesion, assess the completeness of paralysis, determine the need for surgical intervention, the route for approaching the facial nerve and the options for repair (Croxson, 1990). A careful history, noting the nature of the accidental trauma,iatrogenic injury, otological disease or neoplasm, is required. The duration of paralysis is impor-

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Chapter 2 i

tant, with extratemporal facial-nerve lesions requiring immediate exploration to enable identification of the distal ends of the divided nerve. Disruption of the intratemporal portion of the facial nerve should be repaired withinamonth of injury to providethe best neurobiological conditions for regrowth (Conley, 1986; May, 1986b). Nervesubstitutionprocedures, such as facial-hypoglossal anastomosis, should be undertaken within 18 months,prior to neuromuscularend-plate degeneration. Neuromuscular substitution, such as temporalis transfer, can be undertaken at any time following irreversible injury, providing satisfactory neurological function of the donor muscle is established (~cLaughlin,1953; Rubin, 1991). Careful clinical appraisal of the facial-nerve function is required to determine the completeness of paralysis, the presence of segmental or global paralysis and the function of the contralateral side (Croxson, 1990). The other cranial nerves should be examined, especially whencontemplating nerve substitution procedures, such as facial-hypoglossal anastornosis. This requires not only the presence of a normal hypoglossal nerve, but also functioning glossopharyngeal and vagus nerves to ensure that swallowing is satisfactory postoperatively (Sobol, 1991). A normal contralateral facial nerve is required prior to cross-facial anastomosis, and, in general, neurofibromatosis type I1 is a contraindication for nerve substitution procedures. Otological examination not only determines the pres-

ence of related otological disease, but establishes hearing thresholds in the ipsilateral and contralateral ear. The presence or absence of hearing dictates the surgical approach to the facial nerve in its intratemporal segment. A general assessment of the patient’s fitness for prolonged anaesthesia and consideration of the patient’s age, if middle cranial fossa surgery is contemplated, are required. The incidence of temporal-lobe infarction and epilepsy increases with advancing age after middle cranial fossa surgery (House & Shelton, 1994).

nvestigations Imaging of the facial nerve is best performed with a combination of high-resolution CT scanning and MRI. The high-resolution CT scanning provides details of the bony conduit of the intratemporal portion of the facial nerve, giving details of fracture, discontinuity and bone erosion. MRI imaging provides evidence of infection, tumour and sometimes trauma, according to the degree of breakdown of the vascular integrity. MRI is invaluable for assessment of the CPA and soft tissues of the parotid and skull base. Electrophysiological assessment, using EMC, evoked EMG andtranscranial magnetic stimulation, determines the degree of degeneration of the facial nerve (Kartush et al., 1987). In general terms, surgery for traumatic lesions of the facial nerve should not be undertaken unless

Fig. 17.1 The facial nerve in the cerebellopontine angle: retrosigmoid craniectomy, left side.

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complete electrophysiological degeneration of the facial nerve is proved (May, 1986a). Audiological thresholds in both ears are established preoperatively, and dictate the approach to the facial nerve intratemporally. Topognostic tests are of no significant help in site-oflesion testing; however, assessment of lacrimation is helpful in determining the level of eye care required perioperatively (Croxson, 1990).

For surgical purposes, the facial nerve hasthree segments: the CPA and internal auditory meatal portion, the intratemporal portion and the extracranial portion related to the parotid gland. The CPA portion arises as thefacial nerve, along with the nervus intermedius, leaves thebrain stem at the pontomedullaryjunction (Fig. 17.1). Togetherwith the vestibulocochlear nerve, the facial nerve traverses the CPA, entering the porous acousticus and travelling approximately 1cm within the internal auditory canal (IAC) (Fig. 17.2). In crossing the CPA, the facial nerve runswiththe two divisions of the vestibulocochlear nerve and the nervus intermedius, passing anterior to the anterior inferior cerebellar artery and its branch, the labyrinthineartery.Withinthe IAC, the facial nerve rotates with respect to the cochleovestibular nerve to lie in the anterior superior quadrant of the canal, finally being separated from the superior vestibular nerve by Bill’s bar.

Fig. 17.2 The internal auditory meatus: lateral view.

Fig. 17.3 Intratemporal facial nerve.

The intratemporal portion of the facial nerve is further divided into three segments: the labyrinthine portion, the tympanic portionand the mastoid portion(Fig. 17.3). Thelabyrinthineportion commences at the meatalforamen,thenarrowestportion of the facialnerve canal measuring some 0.67mm in cross-sectional diameter (Fisch, 1981). After entering the foramen, the nerve swings sharply anteriorly, forming the geniculate ganglion, fromwhichthegreater superficial petrosal nerve arises. Here, the facial nerve is related to the basal turn of the cochlear and the ampulla of the superior semicircular canal. It is commonly dehiscent or covered by a thin shell of bone visible in the floor of the middle cranial fossa. The nerve turns sharply posteriorly and enters the tympanic portionof its course horizontally in close proximity to the tensor tympani, processus cochleariformus, horizontal semicircular canal,oval window niche and stapes superstructure. The tympanic portion is encased in the bone of the Fallopian canal, which has variable size dehiscences in up to 50% of cases (Schunknecht, 1976). The tympanic portion ends at the second genu to descend into the mastoid portion related to the fossa incudus, horizontal semicircular canal, sinus tympani and facial recess. The mastoid portion of the facial nerve then extends to the stylomastoid foramen, with its vertical course being related to the posterior semicircular canal ampula, the tympanic annulus inferiorly, the retrofacial air cells and the jugular bulb.

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Chapter 17

-

~~

Fig. 17.5 Ultrastructure of a peripheral nerve.

Fig. 17.4 The extratemporal facial nerve: anatomical variations. (Modified from Davis et al. (1956)Surgical anatomy of the facial nerve. Surg. Gynecol. Obstet. 102, 385-412. By permission of Surg. Gynecol. Obstet., now known as theJournal of the American

auricular nerve is a sensory branch of the cervical plexus. The nerve winds around the posterior borderof the sternomastoid at the junction of its upper and lower halves. It branches close to the angle of mandible, supplying the skin around the mastoid and the external surface of the auricle. The external course of the great auricular nerve can easily be mapped by marking the tip of the mastoid, the angle of the mandible, bisecting the distance, and dropping a perpendicular line inferiorly. Approximately 3cm of greatauricular nerve can be harvested for nerve interpositionfrom this site (Fig. 17.6). Thesural nerve is formed by thejunction of the medial sural cutaneous nerve and the peroneal commu-

College of Surgeons.)

The extratemporal portionof the nerve commences at the stylomastoid foramen, coursing inferiorly and laterally around the styloid process, enteringtheparotid gland and dividing intotwo majortrunks, variably branching within the substance of the parotid to form the temporal, zygomatic, buccal, marginal mandibular and cervical branches (Fig. 17.4). The ultrastructure of the motor portion of the facial nerve is typical of that of a peripheral nerve. The constituent fibres are arranged in bundles and fascicles, and three connective-tissue sheathes surrounding the fascicles are recognised. The entirenerve is surrounded by an epineurium, the sheath enclosing a bundle of fascicles is known as the perineurium, and individual nerve fibres have a delicate covering of connective tissue termed the endoneurium (Fig. 17.5). Thegreatauricular nerve and thesural nerve are commonly used as donors for grafting purposes, to reconstitutethe integrity of the facial nerve. Thegreat

Fig. 17.6 The great auricular nerve: surface landmark.

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paralysing ariaesthesia and the avoidance of lignocaine in any local infiltration. Vasoconstriction best is achieved using a solution of 1:100 000 adrenaline with one ampoule of POR-8 (Ornipressin, 5iulampoule Sandoz) drawn up to 20ml of solution.

When the proximal origin of the facial nerve is unavailable for anastomosis, nerve substitution is required to reaminate the face. Other ipsilateral cranial nerves, e.g. the hypoglossal nerve, are commonly used. However, the contralateral facial nerve may also be used via crossfacial anastomosis. Facial hypoglossal anastomosis is a simple, reliable, one step reamination procedure. ~acial-h~poglossal anastomosis Fig. 17.7 The sural nerve: surface landmarks.

nicating branch of the common peroneal nerve, which joins between the two heads of gastrocnemius. The sural nerve passes with the short saphenous vein to the back of the lateral malleolus and continues forward to the lateral side of thefoot,innervatingthe fifth and the lateral portion of the fourth toes (Fig. 17.7). There are several small but useful branches of thesural nerve distal to the lateral malleolus, which can be harvested as a branched graft. Thenerve can be traced medially up to the origin of the two heads of gastrocnemius, providing up to 15cm of nerve if required. The sensory deficit associated with harvesting this nerve is minor and relates only to the lateral side of the foot.

Anaesthesi Procedures on the facial nerve are suited best to general anaesthesia,with techniques avoiding neuromuscular paralysis being essential for all procedures where nerve integrity is being tested. Approaches to the CPA portion of the facial nerve require a three-pin head fixation and osmotic dehydration to shrink the brain with appropriate venous and arterial pressure monitoring.Catheterisation of the bladder is essential and facilities for electrophysiological monitoring of the facial nerve and auditory nerve are desirable. Surgical procedures on temporal the and extratemporal portion of the facial nerve require non-

The patient is positioned supine on the operating table with a pillow placed under the ipsilateral shoulder and the head extended to the contralateral side. A standard parotidectomy incision is made, extending theneck incision in the second skin crease towardstheposterior border of the hyoid. The neck portion of the incision is deepened to identify thegreatauricular nerve in its relation to the external jugular vein. The nerve is dissected distally if required, or transected proximally to allow exposure of the deep cervical fascia. The external jugular veinis divided. The deep cervical fascia is opened to expose the anterior border of the sternocleidomastoid muscle. The anterior edge of the sternocleidomastoid muscle is exposed up to the mastoid tip. The posterior belly of digastric is located between themastoidtip and the angle of the jaw and tracedanteriorly to theintermediatetendon of the digastric at the hyoid. The common facial vein is usually encountered during this step and divided if necessary. The hypoglossal nerve is located anteriorly to the sternocleidomastoid muscle overlying the carotid bifurcation and below the posterior belly of digastric (Fig. 17.8). Thenerve is mobilised and held gently in a vessel loop while peripheral dissection proceeds. Venous tributariesoftencrossthe nerve andrequirebipolardiathermy. Distal dissection continues until thehypoglossal nerve spreads and flattens over the hyoglossus muscle. Proximal dissection of the hypoglossal nerve requires division of thesternocleidomastoidbranch of the postauricularartery, allowing dissection back to the descendens hypoglossi branch. The descendens may be divided to provide extra length for the hypoglossal seg-

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Chapter 17

Fig. 17.8 Hypoglossal nerve: relationship to posterior belly of the digastric and great vessels. (a) Superficial dissection. (b)On retraction of posterior belly of the digastric and the sternocleidomastoid muscle.

ment of the anastomosis, but this is not usually required. A tunnel is thencreatedundertheposterior belly of digastric to facilitate transfer of the hypoglossal nerve to the anastomosis site. The facial nerve is then exposed. Thepreauricular incision is deepened over theanterior surface of the tragus and the cartilaginous pointer is identified at the insertion into the tympanic bone. The posterior belly of digastric is traced back to themastoid tip, and the anterior belly of sternocleidomastoid is visualised inserting into the mastoid tip. The tympanomastoid sutureis then displayed by blunt dissection, and the facial nerve located approximately 1cm deep to thecartilaginous pointer (Fig. 17.9). The hypoglossal nerve is divided as distally as possible. The facial nerve is then divided as proximally as possible at’the anterior surface of the mastoid tip. The hypoglossal nerve is then passed undertheposterior belly of digastric to lie withouttension at the facial nerve stump. Using the operating microscope, a neural anastomosis is performed using three to four sutures of 1010 Neurolon to accurately oppose the two nerves. A variation of facial-hypoglossal nerve anastomosis is the so-called facial-hypoglossal ‘jump graft’ (May et al., 1991; Fig. 17’.10). Thefacial and hypoglossal nerves are displayed as outlined above. The great auricular nerve previously displayed is transected distally and traced back to its emergence at Erb’s point. A segment of nerve approximately 3 cm long is obtained. Using the operating microscope, the hypoglossal nerve is then partially transectedin an obliquemanner to divide approximately 50% of its axon fibres. The great auricularnerve is then reversed and a careful neuralanastomosis is

Fig. 17.9 Relationship of facial nerve to sternocleidomastoid, posterior belly of the digastric, tympanic bone and tympanomastoid suture.

performed between the partially transected hypoglossal nerve andthe distal stump of the facial nerve. The advantage of this procedure is preservation of tongue function. The disadvantage,however, is that the amount of power translated to facial function is generally less than that of a complete hypoglossal nerve section.

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Fig. 17.11 Cross-facial-nerve anastomosis: sural nerve conduit.

Fig. 17.10 Facial-hypoglossal jump graft.

Cross-facial-nerve grafting

The cross-facial-nerve graft is undertakenwhenthe proximalend of the facial nerve is unavailable for anastomosis. A typical example of this is paralysis following acoustic neuroma surgery where the proximal end is lost at the brain-stem origin. Two surgical teams can significantly decrease the time of this procedure. The operation is usually performed in two stages. The first stage places a sural nerve conduit from the functioning side to the non-functioning side. The second stage joins thesural nerve conduit to the paralysed facial nerve stump (Fig. 17.11).Staging the procedure with an interidentification val of 9-12 months provides forthe histologically of budding axons in the distal sural nerve cable prior to anastomosis. The peripheral segment of the paralysed facial nerve can be kept viable by the use of a facial-hypoglossal jump graft at the time of the first stage of sural nerve cabling to prevent neuromuscular degeneration (May et al., 1991). Parotid incisions are made on the donor and receiver side. Onthedonor side, the skin is elevated off the parotid fascia in the superficial musculo-aponeurotic system (SMAS) plane. Dissection proceeds uqtil the buccalfatpad is reached immediately anteriortothe masseter muscle. Dissection in the buccal fat pad using microscope or loop magnification and the facial-nerve stimulator provides identification of the buccal branches

of the facial nerve. A number of branches of the nerve will be identified and thefunction of each branch is confirmed by electrical stimulation.A large branch whose action is also performed by other smaller branches is identified and nominated as the redundant branch to be the donor. The paralysed or receiver side is then approached by the second surgical team, while the first team harvests thesural nerve fromthe leg. Theparotid incision is deepened and the facial nerve is identified using the cartilaginous pointer, tympanomastoid suture, posterior belly of digastric and stylomastoid muscle as described above. The suralnerve is harvested after identifying the nerve posteriorly to the lateral malleolus of the fibula. The nerve is sectioned distally and passed into a rigid vein stripper.The dissection proceeds proximallythrough multiple stepladder incisions to allow up to 15cm of nerve to be harvested. The length of nerve required is carefully measured from the buccal branch of the donor site to the stump of the receiver facial nerve. The sural nerve is then tunnelled from the donor side to the recipient side. This is facilitated by using a small inverted-V incision at the root of the membranous nasal columella. A trocar and small segment of the attached drainage tubing of a Haemovac drain is then used to place the graft. The reversed sural nerve is secured by a suture within the plastic tubing of the Haemovac. The trocar of the Haernovac is then inserted from the anterior limit of the dissected donor site throughthe inverted-V incision atthe columella. Thetrocarand drainage tubing are pulled through, leading the sural

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nerve graft atraumatically into position. The procedure is repeated to reposition the donor nerve into the recipient field. At this stage thedistal end of the recipient nerve is marked with non-absorbable a suture and a microanastomosis to the donor buccal branch of the facial nerve is performed. A facial-hypoglossal nerve ‘keeper’ graft is performed as described above. Alternatively, if a one-stage procedure is desired, the facialnerve trunk is divided and a neural anastomosisbetween the sural nerve and the facial nerve is performed.

Nerve repair or neural coaptationis performed to reconstitute the integrity of the facial nerve. It is desirable to coaptthe nerve using oneanastomosis,as multiple anastomoses descrease the population of budding axons penetrating the peripheral portion of the nerve. However, it is better to use a cable graftwith two anastomoses than a primary anastomosis under tension. Neural coaptation

Neural coaptationis best performed using microsurgical techniques. The nerve endings are mobilised and apposition is ensured without tension. The ends to be anastomosedare cleanly transected using neurectomy shears. The epineurium is carefully resected back approximately 5mm from the junction site. The fascicular bundles are identified and, using a 1010 Neurolon suture, accurately approximated with loose sutures.Theminimumnumber of sutures isused to accurately approximate the nerve, thus minimising the foreign-body reaction at the site of anastomosis (Fig. 17.12). Placing conduits around the neural anastomosis is not required, as fibrosis is generated from the connective-tissue elements of the nerve ratherthanthesurrounding tissue. Neural anastomosis within the temporal bone often requires no sutures if 50% or more of thebony Fallopian canal can be preserved. By this technique, the donor nerve can be placed within the Fallopian canna1 and the anastomosis approximated and held in position by a temporalis fascia graft. Withinthe CPA, neuralanastomosis is technically difficult. The facial nerve in this positionhas an extremely thin glial convering and the suture anastomosis may be impossible. In this situation,the use of a connective-tissue tubeconstructedfromamoderate sized vein may be possible. The vein tube is harvested

and then dried over a Rosen needle shaft and longitudinally split. The proximal end of the facial nerve can be teased into the connective-tissue sleeve and secured using tissue glue. The distal segment of the facial nerve or alternatively a cable graft can be similarly secured. The persistent bathing of cerebrospinal fluid (CSF) and the deep location of the nerve in the CPA make all proximal anastomosis techniques difficult. Surgical repair of the facial nerve in the cerebellopontine angle and internal auditory meatus

The patient is placed in the lateral ‘park-bench’ position on the operating table with thehead held in three-point fixation. The surface markings of the transverse sinus, sigmoid sinus and mastoid tip are marked. A 3 cm circular craniectomy is marked centred on the concavity of the sigmoid sinus. A lazy-S incision centred over the planned craniectomy is performed. The incision is deepened, dividing the occipital vessels and incising the muscular insertions in the apexof the posterior triangle. The lateral skull base is exposed with the mastoid bone and thetip on view anda4cm area of the skull base posteriorly. A high-speed drill is used to locate the sigmoid and transverse sinuses and a 4cm craniectomy is fashioned based behind and inferior to these landmarks (Fig. 17.13).The circular bone plug is removed, dealing with any bleeding of emissary veins leading to the sigmoid sinus by ligation or Surgicell packing. A dural opening based anteriorly on the sigmoid sinus is then fashioned. The basal cisterns arepunctured and CSF is aspirated to allow the lateral lobe of the cerebellum to subside from the operative site. With mannitol dehydration, a wide view of the cerebellopontine angle is afforded without cerebellar compression or resection. The posterior lip of the internal auditory meatus (IAM) can thenbe drilled away using a high-speed drill and the segment of facial nerve from the root entry zone to the lateral portion of the IAM is displayed. Surgical repair of the facial nerve in the intratemporal course

~ranslabyrinthineexposure o f the facial nerve Translabyrinthineapproach to the facial nerve is the procedure of choice in the absence of useful hearing in the operative ear. Thefacial nerve can be easily accessed from theIAM through tothe stylomastoid foramen. The procedure can be accompanied by partial or total temporal bone resection with blind-sac closure of the exter-

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Fig. 17.12 Neural coaptation. (a) Suture repair. (b) Sutureless repair. (c) Vein conduit/tissue glue.

nalauditorycanal(EAC)andfatobliteration of the cavity if desired. This procedure is especially useful for extensive traumaticfractures of thetemporal bone where significant CSF leaks occur or where the dura is widely opened to accomplish nerve repair. The patient is placed supine on the operating table with the head elevated and slightly extended. A wide postauricular incision is performed (Fig. 17.14). If blind-sac closure is anticipated, an anteriorly based periosteal flap is raised and the tissues of the EAC are mobilised prior to deep transection of the EAC. A complete simple mastoidectomy is performed.The facial nerve is fully displayed in its descending portion. The posterior external canal wall is preserved. The epitympanum is widely opened, the incus removed and the head of malleus removed, The tympanic portion of

the facial nerve is then displayed and followed to its proximal extent in the anterior epitympanum. A complete osseous labyrinthectomy is performed commencing withthehorizontal semicircular canal, identifying and removing the posterior semicircular canal, tracing the subarcuate artery beneath the superior semicircular canal and then removing thecanal.The osseous labyrinth is opened, taking carenot toinjury the second genu of the facial nerve, which is now lateral to the dissection. The IAM is defined using the subarcuate artery, superior petrosal vein, posterior fossa dura, medial surface of the vestibule, jugular bulb, cochlear aqueduct and IXth cranialnerve as landmarks. Bone removal fromtheinternalauditorymeatus proceeds from its medial deep portion at the porus towards the distal end, displaying the transverse crest of the internal auditory

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Chapter 17’

Fig. 17.13 Incision for retrosigmoid craniectomy.

through the geniculate ganglion to the tympanic segment. The geniculate ganglion is the commonestsite of traumatic accidental injury. Fractures here are often comminuted and result in a crush type of injury to the nerve. The greater superficial petrosal nerve (GSPN) holds the facial nerve anterior at its first genu. The GSPN is usually not functional following temporal-bonefracture and may direct valuable regenerating facial-nerve fibres away from the main trunk during recovery. Section of the GSPN allows rerouting of the facial nerve, gaining up to 2 cm of additional proximal length (Fig. 1’7.15). The GSPN is sectioned blindly beyond the geniculate ganglion, using a sharp, round knife. Bleeding from the artery of the facial hiatus is encountered and controlled using Surgicell. The proximal end of the facial nerve is now freely mobile fromthe CPA throughthe IAM. Thedistal end of the facial nerve may be mobilised to the second genu to facilitate further length. Primary anastomosiscan be accomplished using 1010 Neurolon.

Fig. 17.14 Transmastoid-middle cranial fossa and translabyrinthine incisions.

meatus last. The superior and inferior vestibular nerves are identified and removed and the facial nerve is then traced from the IAM to the area of Bill’s bar. Bill’s bar is carefully removed with a curette or a diamond drill and the facial nerve is then inspected fromthe IAM

Fig. 17.15 Translabyrinthine exposure of the facial nerve and technique of rerouting.

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~ransmastoid-middlecranial fossa approach to the labyrinthine and tympanic portions of the facial herue The facial nerve can be approached widely, using a combination of thetransmastoid and middle cranial fossa approaches, in the presence of a hearing ear. The patient is placed supine on the operating table with the headof the table raised and the neck extended. The three-point fixation is used to stablise the head. A wide postauricular incision is performed extending from the superior temporal line to the hairline at the temples anteriorly and posteriorly down to the mastoid tip. A complete cortical mastoidectomyis performed to expose the descending portion of the facial nerve with preservation of theposterior EAC. Thetympanic segment of facial nerve is inspected following removal of the incus and head of malleus. Using a diamond burr, the tegmen plate of the epitympanum is thinned, but preserved. The tympanic portion of the facial nerve is traced anteriorly and a subtemporal exposure of the geniculate ganglion is carefully performed using a diamond drill and irrigation. The bone of the tegmen in this area is removed and the dura marked with methylene blue. A 4cm craniectomy is fashioned over the root of the zygoma and placed with reference to the EAC. The dura of the middle cranial fossa floor is visualised and elevated, with the posterior edge of the temporal bone being displayed along the line of the superior petrosal sinus and the area of the geniculate ganglion identified by the methylene blue markfrom below. Using the operating microscope, the geniculate ganglion is easily found in this manner, with the tympanicsegment of the facial nerve being inspected from above following judicious removal of the bone of the tegmen. The labyrinthine segment of the facial nerve can then be identified by tracing the tympanic portion of the nerve into the IAM. Rerouting of the facial nerve by section of the GSPN can be done easily through this approach with direct identification of thegreater superficial petrosal nerve and bipolarcoagulation of thearteryrunning in the facial hiatus (Fig. 17.16). The floor of the middle cranial fossa should be reconstituted using fascia lata, split calvarial bone or temporalis muscle reflected into the floor of the middle cranial fossa. Ossicular chain reconstruction can be performed either primarily or at a second stage after ensuring the sensory neural thresholds are preserved.

Fig. 17.16 Middle cranial fossa floor and technique of rerouting.

Surgical repair of the facial nerve in the extratemporal course: paroti~ectomy

The extratemporal portion of the facial nerve may be repaired by a primary coaptation in sharp penetrating injuries or delayed repair in the case of infected wounds or gunshot injures. Alternatively, cable graftingwith straight or branched grafts canbe undertaken in the case of resection of the parotid andfacial nerve where proximal and distal segments have been preserved. The technique of facial-nerve identification via parotidectomy approach has been dealt with in the section on facial-hypoglossal anastomosis. It should be noted that penetrating wounds of the parotid associated with facial paralysis should be explored as soon as possible. This facilitates location of the distal portionsof the facial nerve by electrical stimulation prior to Wallerian degeneration taking place. In general, clean, penetrating injuries can be treated with primary closure. Gunshot wounds, dog bites or injuries associated with significant tissue destruction should be managed by debridement, systemic antibiotics and secondary closure.

When the peripheral neuromuscular end organ is absent through surgical ablation atrophy, or a new neuromuscular system may be brought in to rehabilitate the face. Temporalis transfer is a simple, reliable tech-

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Chapter 17

Fig. 17.17 Ternporalis transfer. (a) Incision. (b)Reflecting temporalis fascia to elongate graft. (c) Transfer completed.

nique using local tissue, an independent neural supply and provides instant, useful, dynamic reamination.

The patient is placed on the operating table with the head turned to the contralateral side. A parotidectomytype incision is marked out, but the superiorlimb of the incision is extended upwards into the hairline to overlie the middle portion of thetemporalis muscle. The nasolabial crease is also marked, with the vectors of the smile on the functioningside noted and translated by the use of arrows on to the paralysed side. A 1cm wide shave of the hair in the temporal areais then performed, and the hair carefully parted, using Opsite spray to hold it in position. The incision is made and deepened onto the temporalis fascia and further to reveal the superficial parotid fascia and thelayer of SMAS. The midportionof thetemporalis muscle is displayed and a segment of temporalis muscle equivalent to two fingers’ width is outlined using methylene blue. The temporalis muscle is then traced downto the zygomatic arch anda pad of fat overlying the muscle immediately above the zygomatic arch is identified. Thisfatpad is elevated anteriorly taking care to preserve its blood supply. At the end of the procedure the fat pad will be replaced to help prevent indentation over thetemporalis fossa wherethe muscle has been elevated. Themidportion of the temporalis muscle is then incised upto thesuperior temporal line and elevated along with the periosteum on the deep side of the muscle down to the zygomatic arch.Additional length of thetemporalis muscle slip

can be obtained by carefully reflecting the temporalis fascia adherent to thetemporalis muscle fromthe zygomatic root of the muscular flap uptowards thesuperiortemporal line (Fig. 17.17). This reflected fascia is then reinforced using non-absorbable 3/0 sutures. The extra length of temporalis fascia can then be used to reanimatethe lower lip if desired. A nasolabial incision is then performed. A tunnel in the plane of SMAS between the parotid incision and the nasolabial crease is then created. The tunnel should be wide enough to allow passage of two fingers lying flat, thus avoiding the possibility of bunching the temporalis muscle. The temporalis fascia is divided longitudinally, cresting two or three segments according to the number of insertion points chosen. To determine the sites of insertion around the oral commissure and nasolabial crease, theorbicularisoris is grasped through the nasolabial incision and pulled in the direction indicated preoperatively by the arrows of movement. Once chosen, thetemporalis fascia is sewn securely intothe orbicularis oris muscle or the nasolabial tissue to recreate the smile. Sutures of 210 nylon are used, aiming to significantly overcorrect theparalysed side, as stretching of the temporalis muscle will occur. In closing the nasolabial incision, de-epithelialisation of the inferior portion of the incision can facilitate the creation of the nasolabial ‘tuck’ to further emphasise the healed nasolabial crease.

Patients undergoing intradural surgery should be nursed

Surgery of the FacialNerve in an appropriate neurosurgical intensive care unit, until their neurological status is defined and stable. Temporal and extratemporal surgery of the facial nerve requires only otological nursing. Eye care is important perioperatively, and lubrication, humidity chambers andtarsorrhaphyor gold-weight insertion can be used to protect the paralysed eye while awaiting reanimation. Wound care is important, as perioperative sepsis endangers successful nerve grafting. Physiotherapy is of greatimportancenot only for maintaining tone and blood supply during the period of flaccid paralysis, but for promoting appropriate use of nerve and muscle substitution operations and tomaximise partialreturn in the case of incomplete recovery. Physiotherapy begins when all wounds are healed and, in the case of temporalis transfer, 6 weeks from the time of surgery.

Complications Intradural complications include neural or vascular injury at the time of the procedure, postoperative intradural bleeding, infection leading to meningitis and postoperative CSF leak. Careful attention to haemostasis, watertight closure of the dura if possible, the use of fat obliteration in combination with blind-sac closure and perioperative antibioticssignificantly reduce these complications. Translabyrinthine surgery may be complicated by CSF leak if the IAM is widely opened. Packing the IAM, mastoid and labyrinthine cavities and obliterating the middle ear and Eustachiantubewithfat reduces the chance of leak. Perioperative lumbar drainage is generally successful in controlling postoperative leaks. The transmastoid and middle cranial fossa procedure is complicated by sensory neural hearing loss in approximately 10% of cases due to inadvertent injury of the basal coil of the cochlea or ampulla of the superior semicircular canal. This can be minimised by accurately identifying the geniculate ganglion from below prior to middle cranial fossa exploration of the IAM.

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Extratemporal procedures involving the parotid are complicated by haematomaformation, infection and possible salivary fistula. In general, perioperative antibiotics in theform of cephazolin are used to minimise operative site infection and promote successful neural regeneration.

Conley J (1986) Perspectives in facial reanimation. In: May M (ed.) The Facial Nerve. New York, Thieme, pp. 645-63. CroxsonG (1990)The assessment of facial nerve dysfunction. J. Otolaryngol. Soc. Aust. 6 (4), 252-63. Davis, Anson, Puddinger & Kurth (1956) Surgical anatomy of the facial nerve. Surg Gynecol Obstet 102, 385-412. Fisch U (1981) Surgery for Bell’s palsy. Arch. Otolaryngol. 107,l-11. Harrison D (1985) Thepectoralis minor vascularized muscle graft for the treatment of unilateral facial paralysis. Plast. Reconstr. Surg. 75, 206-1 2. House W & Shelton C (1994)The middle fossa approach. In: Brackmann D (ed.) Otologic Surgery. Philadelphia, W.B. Saunders, pp. 595-604. & Kernink JL (1987) Kartush JM,Niparko JIC, GrahamMD Electroneurography: preoperative facial nerve assessment for tumours of the temporal bone. Otolaryngol. Head Neck Surg. 91 (3), 257-6 1. McLaughlin C (19.53) Surgical support in permanent facial paralysis. Plast. Reconstr. J.11, 203-1 1. May M (1986a) Trauma to the facial nerve. In: May M (ed.) The Facial Nerve. New York, Thieme, pp. 421-40. May M (198613)Surgical rehabilitation of facial palsy: total approach. In: May M (ed.) The Facial Nerve. New York, Thieme, pp. 695777. May M, Sobol S & Mester S (1991) Hypoglossal-facial nerve interpositional-jumpgraftfor facial reanimation without tongue atrophy, Otolaryngol. Head Neck Surg. 104, 818-25. Rubin L (1991) Reanimation of total unilateral facial paralysis of the contiguous facial muscle technique. In: Rubin L (ed.) The Paralysed Face. St Louis, Mosby-Yearbook, pp. 156-77. Schusknecht H (1976) Anatomy. In: Schuknecht H (ed.) Pathology of the Ear. Cambridge (MA), Harvard University Press, p. 39-40. Sobol S (1991) Hypoglossal-facial anastomosis: its role in contemporary facial reanimation. In: Rubin L (ed.) The Paralysed Face. St Louis, Mosby-Yearbook, pp. 137-43.

MICHAEL J. GLEES BEN PANIZZA

No aspect of otologyhas been morecontroversial than the surgical treatment of vertigo. The controversy persists, shows no sign of abatementand regularly precipitates heated discussions. There are three fundamental reasons for this diversity of opinion. First, vertigo is asymptomfor which there is amultitude of causes. Second, precise diagnosis can be extremely difficult, if not impossible, notwithstandingthefact that there is often spontaneous resolution. Third, the cornmonest indication for surgical intervention in current practice is that of endolymphatichydrops (Menikre’s disease) and it is this that causes so much concern. Despite rigid criteria defining thecondition(Alford, 1972),there is a suspicion by some otologists that others diagnose it too easily or at least prematurely. As 6080% of patients with Menikre’s disease recover almost regardless of their treatment, a large body of otological opinion holds the view that surgical intervention should be reserved forthosewithintractable problems. An equally vociferous number of otologists remain convinced that early treatment both effective is for Menikre’s disease and prevents the condition from becoming intractable. Thepurpose of thischapter is notto enterinto the debate butto provide clear guidelines for surgery on the peripheral vestibular system and to describe techniques currently in use. Nevertheless, the view expressed is that of the authors andreflects their clinical approach to the problem of vertigo, which others may find too conservative. Many of theproceduresadvocated by othersare not particularly challenging and,although not practised by theauthors,thechapterwould be incomplete without them. Description of some of these procedures has been included to provide a comprehensive overview.

Surgery for vertigo is rarely indicated and, in reality, lesions such as cerebellopontine angle (CPA) tumours and perilymph fistulas, for which surgery must be seriously considered, affect few patients. By far the majority of vertiginous patients with strictly otological disease have either recurrent vestibular neuronitis, posttraumatic labyrinthitis or Menikre’s disease. Vestibular sedatives, for example prochlorperazine, are generally effective in those with peripheral vestibular disorders. Menikre’s disease can alsobe controlled in most patients quite satisfactorily with vestibular sedatives, but some may farebetterwith betahistine, saltrestriction and diuretics, either alone or in combination. It is only when these measures have been thoroughly exhausted and the patient’s occupation or life is being destroyed by vertiginous attacks that the clinician should contemplate surgical intervention. Surgery is unlikely to help patients with bilateral vestibular disease and, althoughage is not a direct contraindication, it is prudent to make it a significant consideration. The surgical procedures currently used to control incapacitating vertigo from peripheral causes fall into two categories-conservative and destructive. Conservative procedures aimto preserve hearing and areindicated for those patients with useful hearing in their affected ear. Destructive techniques are reserved forthosepatients whose auditory ability on the affected side is considered to be of little functional use. The criteria for what constitutes useful or serviceable hearing areconstantly changing. In the past, an ear with a speech reception threshold greater than 50dl3, with optimal speech discrimination less than SO%, was considered to be expendable. Nowadays, the threshold for conservation has I20

Surgery for Vertigo become greater. Silverstein et al. (1990)recommend that only ears with a pure tone average greater than 80dB and speech discrimination worse than 20% should be actively destroyed. Before making the decision to operate, the surgeon wouldbe wise to consider three factors. First, the hearingacuity of the contralateral ear.If this is not perfect, it rnay be that the affected ear still provides useful information for binaural hearing and would be better preserved. Second, the possibility that the causative factor might ultimately affect the good ear; hydrops becomes bilateral in a significant number of patients (Haye & Quist-Hanssen, 197’6; Balkany et al., 1980; Silverstein et al., 1992). Third, a patient’s future wellbeing and ability to takeadvantage of new developments and technologies rnay be compromised by a destructive procedure. For example, an intact inner ear is almost aprerequisite for an effective cochlear implant. Bearing this in mind, a labyrinthectomy could preclude future cochlear implantation if auditory rehabilitation became a necessity. It is the authors’ contention that every patient has to be considered on his or her own merits and that destructive proceduresshould be reserved for those with no hearing at all on the affected side or, at the very least, exceptionally little to lose.

weakness oraberrations of taste), trigeminal pain, difficulties in articulation or swallowing not infrequently accompany space-occupying lesions in the cerebellopontine angle or infratemporal fossa. The surgical management of these conditions is dealt within the other chapters of this section. Nevertheless, it is a disquieting fact and salutary lesson that the majority of acoustic neuromas and otherCPA lesions referred to the senior author had been misdignosed as Menikre’s disease for some considerable time, often for periods of several years. Systemic disorders also cause vertigo. Hypertension is

Table 18.1 Causes of vertigo and dizziness.

Preoperative It cannot be emphasised too strongly that the differential diagnosis of vertigo is vast (Table 18.1). Misdiagnosis must be avoided at allcost and every effort should be made to establish the correct diagnosis by careful documentation of the patient’s history and a thorough clinical examination followed by the selection and interpretation of specific investigations. While patients may find accurate description of their symptoms difficult or beyond their capability to express, the surgeon should be absolutely clear that vertigo arising from the vestibular system is a subjective sensation of movement, which is usually rotatory. Patients rnay say that they feel either themselves or their environment moving. General sensations of light-headedness, dizziness or instability are rarely the result of labyrinthine or vestibular-nerve disorders and, in these cases, alternative causes should be sought. Associated auditory symptoms, hearing loss and tinnitus are important featuresto establish and characterise, asthey are stronglyindicative of an otological lesion. Assessment of this deficitis pivotal in subsequent management decisions. A labyrinthine fistula should be seriously considered in patients with otorrhoea and those who have previously undergone surgery forchronic infection or otosclerosis. Symptoms referable to the facial nerve (facial twitching,

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CPA,cerebellopontineangle.

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common, dysrhythmiasless so, while vertigo as thesideeffect of drug therapy is not infrequent. Demyelination and even syphilis should alsobe considered, if only to be excluded. It is theauthors’ practice to undertakeaneurootological examinationfor all patientswith vertigo. This initial examination includes otoscopy, audiometry, evaluation of thecentral nervous system (CNS)and measurement of blood pressure and pulse rate, together with auscultation of the carotid arteries. Audiometric and vestibular tests are tailored to each individual patient’s needs. A pure-tone audiogram (PTA) alone may be adequate for some with absolutely normal, symmetrical hearing who give a classic history of non-otological a condition, for example vertebrobasilar ischaemia. Theaddition of a caloric test might be sufficient investigation for a patient withsymptoms and signs of a benign otological condition,for example post-traumatic vertigo. Moresophisticated tests are indicated and essential in other patients, for example those with asymmetrical or fluctuating sensorineuralhearing loss, and absolutely mandatory for those in whom surgery is considered. We recommend that speech audiometry,stapedial reflex decay measurement and brain-stem-evoked responses are acquired for these patients. They should also have a battery of basic blood tests to include a full blood count and film, indices, biochemical screen and syphilis serology. An M R scan is almost always arranged, to exclude an intracanalicular tumour, and a CT scan performed if surgical intervention is deemed necessary. Containment of expense in the investigation of patients with vertigo has always been a problem for the otologist. Health-care resources are becoming more and more limited every year and attempts to force economies on clinicians aremorefrequent.Thesurgeonshould continually remember thepotential consequences for theirpatient of missing the diagnosis of an acoustic neuroma or otherCPA lesion at anearly stage. For some this could meanapermanently paralysed face and a lifetime’s misery. Weshould not be shy or slow to remind our trusts and institutions that the consequence for them could be a very substantial claim for negligence, which would be difficult to defend. In the UK, incapacitating vertigo precludes driving and also many other activities that might place either the patient or others at risk of bodily harm. While surgical treatment is often successful, patients should notresume driving until they have been free from spontaneous attacks of vertigo for a period of at least 3 months. Standards of medical fitness to hold heavy-goods vehicle and public-service vehicle licences are much more stringent.

In this respect, a history of recurrent vertigo or significant unilateral deafness is more than sufficient to disbar patients from obtaining or renewing their licence (Espir & Godwin-Austen, 1978).

In this section, the authors assume that the reader has a practical understanding and knowledge of basic temporal-bone anatomy. What follows is a description of the crucial anatomical features encountered in the surgical approaches to the peripheral vestibular system.

The retrolabyrinthine approach affords exposure of the vestibulocochlear nerve in the CPA. The component parts of the nerve fuse close to the lateral end of the internal auditory canal but, even though fused, can be separated in the CPA. Three anatomical features facilitate this separation. First, a cleavage plane usually becomes apparent by strokingthe nerve withablunt probe. Second, a small blood-vessel often runs between

Fig. 18.1 Axial CT scan of the temporal bone showing the degree of exposure and access afforded by retrolabyrinthine and retrosigmoid-intracanalicular approaches to the cerebellopontine angle and internal auditory meatus. The deleterious influence that a prominent sigmoid or narrow temporal bone might have on exposure with the retrolabyrinthine approach is apparent.

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Fig. 18.2 Posterior view into the left cerebellopontine angle and internal auditory meatus. The rotation of the constituent nerves in the cochleofacial bundle can be seen between the brain stem and the lateral end of the internal auditory canal.

the vestibular and cochlear divisions. Third, there is a subtle difference in colour between the two nerves, the cochlear nerve being relatively white in comparison with the greyish hue of the vestibular nerve (McKenna et al., 1994). The relative position of the facial to the cochleovestibular nerve changes between the porus of the internalauditorycanal(IAC)andthebrain stem. Within the IAC andatthe meatus,the facial nerve sits anterosuperiorly,the cochlear nerve anteroinferiorly and the superior and inferior vestibular nerves posterosuperiorly and posteroinferiorly, respectively. The nerve bundle then rotates as it passes across the angle, so that the vestibular nerve comes to lie superior or posterosupeiior to the cochlear nerve, with the facial nerve more anterior and inferior (Fig. 18.2). The retrosigmoid-intracanalicular approach,as described later, gives the surgeon the opportunity to open the IAC. This can be useful in those cases where discrimination between the cochlear and vestibular nerves is in doubt as they are only completely separate at the lateral end of the canal (Silverstein et al., 1987’). The limiting factor when opening the IAC is the position of the posterior semicircular canal. Its integrity has to be maintained if hearing is to be preserved. For this reason, the IAC can only be opened a maximum distance of 10rnmfrom its medial end (Domb &c Chole, 1980; Kartush et al., 1984; Roland et al., 1988; Silverstein et al., 1988; Laine et al., 1990). The topographic landmarks of the posteromedial as-

Fig. 18.3 Posterior view of the left temporal bone showing the relationships between the internal auditory meatus, the vestibular aqueduct and the posterior semicircular canal.

pect of the temporal bone include the sigmoid sinus, porus acousticus, operculum (the bony shelf overlying the proximal endolymphatic sac and vestibular aqueduct) and thesubarcuate fossa (Fig. 18.3). However, these landmarks are notreliable guides to the positionof the underlying labyrinth. The posterior semicircular canal is situatedposterior and lateral to the vestibular aqueduct. Other parts of the membranous labyrinth can also be damaged by removal of bone around the IAC. In this respect, it is advisable to begin bone removal around the endolymphatic sac and proceed anteriorly, medial and inferior to the vestibular aqueduct.This protects the integrity of the common crus-the conflu-

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Table 18.2 Distance (in millimetres) of structures from the posterior lip of the internal auditory canal.

Table 18.3 Mean distance (in millimetres) of parts of the labyrinth from the posterior surface of the petrous bone.

PSC, posterior semicircular canal; TC, transverse crest; VEST,

vestibule; CC, common crus.

ence of the non-ampullated ends of the superior and posterior semicircular canals.Tables 18.2 and 18.3 summarise these relationships in a moremeaningful and surgical way-interms of the length of the IAC and distances fromtheposterior surface of thetemporal bone of parts of the labyrinth which are at risk during marsupialisation o f the IAC. The anterior inferior cerebellar artery

The principal blood-vessel in the cerebeliopontine angle is the anterior inferior cerebellar artery(AICA).This vessel arises from the caudal third of the basilar artery and immediately runs downwards andlaterally, usually, though not invariably, ventral to the abducent, facial and vestibulocochlear nerves, towards the CPA. At this point, it forms a loop, which can extend for a variable distance into the IAC below the facial and vestibulocochlear nerves. The labyrinthine artery often arises fromthesummit of the loop and supplies the inner ear. TheAICA then divides into two. One branch, the medial branch, passes tortuously laterally and downwards on the medial and anterior border of the cerebellar hemisphere. After about 1cm, this vessel gives rise to a branchof variable size, which passes posteriorly

along the medial surface of the hemisphere to anastomose with a cerebellar branch of the posterior inferior cerebellar artery (PICA). The other branch of the AICA, the lateral branch, passes directly laterally and curls round the upperedge of the flocculus to lie on the surface of the middle cerebellar peduncle en route to the cerebellar hemisphere, where it anastomoseswith all threemain cerebellar arteries. Branches from the AICA also supply themiddle cerebellar peduncle, the lateral aspect of the pons and upper part of the medulla oblongata (Silverstein et al., 1987) (Fig. 18.4). There is considerable variation in thesize and relative importance of this vessel. Side-to-side diversity is frequent and bears an inverse relationship to the size of the PICA. In other words, if the AICA is diminutive, the PICA on thatside will be correspondingly enlarged. The anastomotic vessel from the medial branch is prominent in cases where thereis gross disparity in size between the PICA and AICA. The relative importance of the AICA and PICA can be inferred from their sizes. Described initially by Wallenburg (1901), occlusion of the AICA can give rise to infarction of the lateral pons and medulla. The neural deficit that develops after the AICA is clipped is variable, reflecting the site of the ligation and the relative contribution of the PICA to local perfusion. Lower cranial-nerve palsies, dissociated sensory loss, hemiplegia, ataxia and autonomic abnormalities have been reported. At worst, it can be fatal, but it is not entirely incompatible with prolonged survival. Middle cranial fossa approach to the internal auditory canal

There are several variations of the middle cranial fossa approach, all of which access the IAC through a temporal craniotomy and the floor of the middle cranial fossa (MCF). Theprocedure described later in this chapter is

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Fig. 18.4 Variations in the anatomy of the anterior inferior cerebellar artery. (a) The ‘classical’ and a fairly common arrangement. (b) The anterior varying inversely with the posterior inferior artery (common). (c)Both posterior vessels small, their areas of supply being chiefly fed by the anterior vessels

(uncommon). (d)Both anterior vessels small, their areas of supply being chiefly from the posterior vessels (uncommon). (e)Anomalous importance of vessel from the junction of vertebral arteries. (f) Rare-posterior vessel being continuation of vertebral artery. (After Atkinson, 1949. With permission of the BMJ Publishing Group.)

known as the transtemporal middle cranial fossa approach,asit relies for access on the removal of supralabyrinthine bone and thereby limits the degree of duralretraction which might otherwise be necessary. These approaches allow access to the lateral end of the IAC, where the separationof the cochlear and vestibular components of the VIIIth nerve is complete and themost accurate section of the vestibular nerve can be achieved. The salient topographical features of the middle cranial fossa are shown in Fig. 18.5. If the tegmen tympani is opened, the head of the malleus and the body of the incus can be seen in theattic.The malleus head is consistently situated 18mm medial to the outer cortex of the squamous temporal bone at the zygomatic root (Catalan0 & Eden, 1993).Medial to the attic, the lateral end of the IAC is related anteriorly to the basal turn of the cochlea and geniculate ganglion, while posteriorly it is related to the vestibule and superior semicircular canal. It must be appreciated that this is a very confined

space, all these structures being within a distanceof just 4 mm of each other (Parisier, 1977). Several methods have been described to locate the IAC throughtheMCF. Somerely on following the greater superficial petrosal nerve from the facial hiatus posteriorly to the geniculate ganglion, from where the labyrinthine segment of the facial nerve can be traced to thelateralend of the IAC (House,1961; Glasscock, 1969). Othersfeel that this technique risks the integrity of the facial nerve and, therefore, Fisch (1970) recommends identification of the superior semicircular canal and using it as a guide to the IAC. The arcuate eminence, which is the prominence of bone near the middle of the superior surface of the petrous temporal bone, is said to be caused by the underlying superior semicircular canal (Anson & Donaldson, 198 la).Unfortunately, this is not always so, and it may deviate from the blue line of the superior semicircular canal by up to 5mm. Sanna et al. (1995) state that it fails to correspond in up

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Fig. 18.5 Salient and schematic topographical features of the middle cranial fossa through a right temporal craniotomy.

to 48% of patients. Kartush et al. (1989, in a study of 60 temporal bones, found that 15% did not have an arcuate eminence and, in those that did, it was rotated relatively posteriorly in 50%. Although this rotation is common, the lateral endof the arcuate eminence almost always remains over thelateral limb of thesuperior semicircular canal. Regardless of this rotation, the arcuate eminence and the blue line of the superior semicircular canal tend to remain almost perpendicular to the petrous ridge and the superior petrosalsinus. Table 18.4 showsthe variability in relationship of identifiable structures to the IAC. The depth from the floor of the middle cranial fossa to the IAC and superior semicircular canal is also variable and may be anything from 1 to 5 mm.

From a surgical standpoint, the endolymphatic sac has two parts: an intraosseous or proximal portion, which is situated in the vestibular aqueduct, and anextraosseous or distal portion, which extends for a variable distance between the periosteal part of the dura and the dura proper (Anson & Donaldson, 1981 b)(Fig. 18.6). It can be found below an imaginary line (Donaldson’s line), drawn along the axis of the lateral semicircular canal,

Table 18.4 Relationship of structures to the internal auditory canal, expressed in degrees.

which bisects the posterior semicircular canal into superior and inferior segments. The sac lies medial to the vertical segment of the facial nerve and is initially visible during dissection as a thickening of the posterior fossa dura,impartingawhitishcolour to it.Theexternal aperture of the vestibular aqueduct, through which the sac passes, is marked by a lip of bone, Irv’s ridge, in approximately 65% of patients (Arenberg et al., 1987). If present, this ridge is easily palpable with a probe and is a useful guide to the superior extentof the sac. Friberg et al. (1988) showed that the sac was usually widest at theexternalaperture of the vestibular aqueduct. For shunt procedures, opening near the vestibular aqueduct is therefore recommended.

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very sclerotic, the retrosigmoid-intracanalicular approach can even be used for an ear in which there has been previous infection or had an intervention for sepsis. On the other hand, if the petrous apex is very well pneumatised, opening the canal could be unwise.

Fig. 18.6 Right mastoid cavity showing the relationships of the endolymphatic sac to the facial nerve, post semicircular canal and jugular bulb.

Vestibular neurectomy and saccus decompression are themost frequently performed surgical interventions. Neither should be contemplated on the onlyhearing ear. While vestibular neurectomy may be effective for incapacitating peripheral vertigo from any cause, saccus decompression is only appropriate for the managementof endolymphatic hydrops. Three conservative approaches arecurrently employed by otologistsfor vestibular neurectomy-the middle fossa, the retrolabyrinthine and the retrosigmoid-intracanalicular approaches. Each will be described and their merits, advantages and disadvantages discussed.

This is a relatively simple procedure,provided that the surgeon is familiar with the anatomy of the CPA. It offers excellent exposure of the angle for identification of the cochlear, vestibular and facial nerves, together with the subarachnoid blood-vessels, in particular the AICA. Thisapproach is particularlyappropriatefor those cases in which the sigmoid sinus is prominent or anteriorly placed. As the bone around the IAC is normally sclerotic, the mastoid air-cell system is not usually opened, even though the canal wall is taken down. If

Patients must give fully informed consent. There should be no doubtin their mindsthat complete success cannot be guaranteed and that there is a very real risk to the integrity of their hearing on that side. In a survey of hearing results following vestibular neurectomy carried out in the USA, 85% of patients achieved a pure-tone average within 10dB of theirpreoperative levels and 8’7% within 20dB. Similarly, 82% had speech discrimination scores within 10% and 91% of patients within 20% of theirpreoperative levels (Silverstein et al., 1992). Although permanent damage to the facial nerve is unlikely, temporary dysfunction may develop. Subcutaneousheparin is not prescribed to prevent thromboembolism. All patients are given prophylactic antibiotics on induction of anaesthesia; IV cephuroxime1.5 g asa single dose is recommended. Facial-nerve monitoring is mandatory andso only shortacting muscle relaxantscan be used at theinduction of anaesthesia. The current trend is also toward intraoperative auditory assessment, by monitoring either evoked auditory-nerve or brain-stem responses. Intact responses at the completion of surgery are comfortingforthesurgeonbut do not guaranteenormal

Fig. 18.7 Retrosigmoid-intracanalicular approach, incision and craniotomy outline.

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Fig. 18.8 Retrosigmoid-intracanalicular approach. A C-shaped incision has been made in the posterior-fossa dura with forward retraction of the sigmoid sinus.

function. Changes in signal during the procedure can help prevent inadvertent damage to both the facial and cochlear nerves. Thepatient is placed on theoperatingtable in thepark-benchposition and theanaesthetistshould be asked to obtaina degree of hypotensioncommensurate with the cardiovascular status of the patient.Lumbarcerebrospinal fluid (CSF)drainage is established routinely. A limited shave is undertaken and the scalp prepared scrupulously with betadine, or other antiseptic agent if the patient is allergic to iodine, before being draped. lncision

A curvilinear retroauricular incision is made within the hairline, as indicated in Fig. 18.7, so that themost posterior aspect is well behind the sigmoid sinus. It is deepened layer by layer, each successive layer being incised slightly anterior to the previous one. This facilitates a stepped watertight closure. Operative steps

A posterior craniectomy measuring 2 X 4cm is made immediately behind thelateral sinus (Fig. 18.7).The posterior fossa dura is opened, using a C-shaped incision so that stay sutures placed in the dural flap can be used to retract the lateral venous sinus forwards. After the cisternal arachnoid is opened, the cerebellum tends

to fall away from the petrous bone and the IAC can be seen. Access can be improved by placing cottonoids over the exposed cerebellum and applying gentle traction. Using the operatingmicroscope at high magnification, the facial nerve is positively identified by stimulation and then the cochleovestibular nerve is examined carefully to detect a cleavage plane. The vestibular component lies superior to the cochlear fibres at this point and has a slightly grey appearance in comparison with the white cochlear fibres. A small blood-vessel often lies on the surface of vestibular nerve, close and parallel to the cleavage plane (Fig. 18.8). Some surgeons even advocate gentle stroking of the nerve with a blunt hook to promote separation. In about 10% of patients, no plane is identified (Silverstein et al., 1992). In these, the IAC can be opened with a diamond-paste burr and the neural bundle traced peripherally until natural separation becomes apparent (see Fig. 18.2). Oncethe vestibular nerve is identified, it is cut with either a sharp hook or microscissors and a small section removed. Closure

Any mastoidair cells that have been openedare obliteratedwith bone wax.Thedura is closed with interrupted 4/0 Vicryl sutures and the layers produced during the soft-tissue incision are reopposed and closed with Vicryl. The skin incision is stapled and Sofratulle stripsare employed asthe first dressing. A crepe mastoid pressure bandage is applied and left in place for 2 days. Postoperative manage men^

Thepatient is kept flat forthe first 48h withthe CSF pressure kept between 0 and2cmH,O while monitoring vital functions. After this period, the drain is closed and the pressure allowed to return to normal. The lumbar drain is removed if there is no sign of CSF leak through either thewoundor the nose after a further 24h. The patient is then mobilised over the next 2 days, after which time they are normally fit for discharge home, with instructions to avoid any strenuous exercise for at least 2 weeks. Throughout thepostoperative period, analgesia can be achieved with codeine, 30--60mg, or other non-narcotic agents. Scalp staplesare removed on the fifth postoperative day. Patients should avoid rapid head movements during the first few months of their recovery and cannot drive until they have been assessed as safe to do so at a subsequent follow-up appointment, which is usually 6 weeks later.

Surgery f o r Vertigo Complications

There are surprisingly few complications. Complete or increased sensorineural hearing loss and transient facial weaknesslastinga few daysarethemostcommon. Wound infection is rareand meningitis has been reported in less than 0.5% (Silverstein et al., 1992). CSF leaks, which plagued the pioneers of these surgical techniques, have been all but eradicated by care in closure and controlledlumbardrainage. Nevertheless, both early and late leaks can develop. Most early leaks will close spontaneously after a period of prolonged lumbar drainage. Those that fail to close and late leaks are best dealt with surgically. The wound is reopened and the defect in the dura ormastoid air cells is identified. Dural defects are repaired with a fascia lata graft, reinforced by a pedicled temporalis-muscle flap. Leaks through the mastoid air-cell system are occluded with bonewax and free muscle grafts. In both situations, lumbar drainage is re-established for a period of at least 48 h, after which time it is clamped for a further24 h to establish that the leak has been finally sealed. Some patients continue to complain of wound pain and headache referred to the ipsilateral temporal and retro-orbital regions formanymonthsafter surgery. This can be severe and exceptionally difficult to control with non-narcotic analgesics. In some patients, this pain may be almost as incapacitating as their vertigo. Fortunately, in. themajority,painimproves or disappears during the first 2 years, but for a few it remains a very significant problem, for which a solutionis rarely found.

129

retrosigmoid-intracanalicular vestibular neurectomy with the ekception that the patient is placed supine on the table with the head turned away from the operative side, as if forastandardmastoidexploration.Intraoperative neural monitoring and lumbar drainage are essential. ~ncisi

A postauricular incision is made 2-3cmbehind the retroauricular sulcus. The skin and subcutaneoustissues are raised and reflected anteriorly, leaving thetemporalis and postauricular muscles, togetherwiththe mastoid periosteum, as a separatelayer. This is raised as a D-shaped, Palva flap, which isbased anteriorly and used as a separate reinforcing layer at closure.

A generous cortical mastoidectomyis performed, bevel-

This is similar in many respects to theretrosigmoid approach. The exposure it offers to the CPA depends largely on the space available between the lateral sinus and the posterior semicircular canal (see Fig. 18.1). In patientswitheither narrowtemporalbonesor very prominent lateral sinuses, access to the cerebellopontine angle can be extremely restricted. As the operation is performed through a cortical mastoidectomy, it cannot be undertaken in an ear where there has been previous infection. Onlythose aspects which differ fromthe retrosigmoid-intracanalicular approach will be described in detail.

ling the edges to gain maximal exposure. The lateral sinus is exposed very carefully, together with the dura immediately behind and in front of it. In some patients, the dura andsinus wall is very delicate and can be easily damaged even with a diamond-paste burr. If it should bleed, haemostasis can be achieved by placing a strip of Surgicel over it, covered by a sliver of muscle and a cottonoid. The posterior semicircular canal is skeletonised and the boneoverlying the endolymphatic duct and posterior fossa dura is removed. A C-shaped incision is made in the dura, based onthe labyrinth, and stay suturesare placed to facilitateanteriordisplacement. The lateral sinus, protected by a wet cottonoid, is then collapsed and compressed with a malleable retractor. The internalauditorymeatus (IAM) and CPA can then be visualised. Exposure, as with the retrosigmoidintracanalicular approach, may be improved by placing cottonoids over the exposed cerebellum and applying gentle traction.Identification and section of the vestibular nerve is as described previously. Unlike the retrosigmoid-intracanalicular approach,it is usually not possible to open the IAC adequately if the cleavage plane between the cochlear and vestibular nerves is not immediately apparent.This is a significant disadvantage, as a definitive plane cannot be found with confidence in up to 10%of patients, and it is these cases that are at greater risk of sustaining iatrogenic sensorineural hearing loss.

Preparation

Closure

Operatiue techniqueretrolabyrinthine vestibular neurectomy

Preparationforsurgery

is identical tothat

of the

The dura is closed very

carefully with interrupted 410

I 30

Chapter 18

Vicryl sutures. Although lumbar CSF drainage has dramatically reduced the incidence of CSF leak in this procedure, the authors are reluctant to rely solely on this measure and they include mastoid obliteration with fat forits prevention. It is better to reinforce thedural closure with an inferiorly based temporalis muscle flap, sutured to the dura in two or three places for retention. The mastoid cavity is then obliterated with abdominal fat, which is held in place by return of the Palva flap. Closure of the skin is undertaken in layers with Vicryl and either 4/0 nylon or staples. Sofratulle stripsare placed over the incision as the first dressing and a crGpe mastoid pressure bandage is applied and left in place for 2 days.

In terms of consent, prophylactic antibiotics, skin preparation and intraoperative monitoring, preparation for this operation is the same as that for the retrosigmoidintracanalicular and retrolabyrinthine procedures. Lumbar drainage is useful but not essential. Hair is removed from the parietotemporal region and patients are placed on the operating table in the supine position with their heads turned away from the operative side. The surgeon is seated at the head of the table rather than the conventionalposition to one side asinother mastoid procedures. Incision

Posto~er~tive

Postoperative care is identical that to retrosigrnoid approach.

Preparation

A preauricular incision, with its inferior limit just below of

the

Complete or increased sensorineural hearing loss and a transient facial weakness lasting a few days are the most common complications. Using the closure technique described above, CSF leaks are most unusual and, at most, temporary. Infection is very rare indeed and, unlike the retrosigmoid-intracanalicular approach, headache is not a problem.

the zygomatic arch, is extended into the temporal region. The incision angles forwards just above the superior attachment of the helix, this extension measuring about 7-8 cm (Fig. 18.9). Some surgeons prefer to combine thesupralabyrinthineapproachwithamastoid exploration. This has the advantage of allowing identification of the facial nerve in its tympanic and mastoid segments, positions familiar to all otologists. Potholes can then be made in the tegmen above the tympanic segment of the facial nerve to facilitate surgical orientation when viewed from above through themiddle fossa.

This approach is technically more difficult than those previously described but has two significant advantages. First, it identifies the vestibular nerve in the lateral portion of the IAC, at a point in its couse where the vestibular fibres naturally separate from the cochlear nerve. It is therefore possible to performa complete vestibular neurectomy. Difficulties indeterminingthe cleavage plane between the component parts of the VIIIth nerve in theCPA are therebyovercome. Second, it is largely an extradural approach to theIAC and, therefore, the possibility of CSF leak and subsequent intracranial infection is minimised. Despite these advantages, the risks to any residual hearing on the operated side are not diminished, and so this procedure should not be undertaken on the only hearing ear. Active middle-ear infection is also a contraindication. Fig. 18.9 Middle-cranial-fossa approach. Preauricular incision from just below the root of the zygomatic arch into the temporal region.

Surgery for Vertigo

13 I

If this technique is employed, the incision has to be modified, the preauricular element being substituted by a postauricular, mastoid, extension. Operative steps

The incision is deepened to expose the temporalis fascia and, in doing so, the superficial temporal vessels are ligated. The temporalis muscle is incised as outlined in Fig. 18.10. This provides adequate exposure of the temporalsquama while defining a pedicled muscle flap, which can be invaluable for closure. Stay sutures are inserted into the flaps to facilitate retraction out of the operative field, and hinged retractors are inserted from above and below to complete the exposure. The position of the craniotomy is of vital importance. Made too wide, the middle-fossa retractor will not engage properly; if too far anterior or posterior, the surgeon will struggle to locate the surgical landmarks and may inadvertently damage the cochlear or facial nerve. A 3 X 2cm craniotomy should be made, centred on the root of the zygoma-in other words, centred just anterior to the external auditory canal (EAC) (Fig. 18.11). Initially, this window of bone can be outlined with a cutting burr but it is prudent to use a diamond-paste burr in the latter stages to avoid laceration of the underlying dura, which is particularlythin and delicate inferiorly. A craniotome is favoured by some to make the craniotomy flap but, because of the fragility of the dura inferiorly, most complete this part with diamondpaste burrs. The bone flap is then carefully elevated with ablunt elevator or dural raspatory. Gentle irrigation

Fig. 18.10 Middle-cranial-fossa approach. Incision of the temporalis muscle.

Fig. 18.11 Middle-cranial-fossa approach. Craniotomy centred the zygomatic root.

on

with saline is often helpful. Once elevated, the bone flap is placed in normal saline or Ringer’s solution. It is very important that the dura stays intact and branches of the middle meningeal vessels are not damaged during this part of the procedure. The edges of thecraniotomyaresmoothedwitha rongeur and the inferior margin is lowered, level with the floor of the middle cranial fossa. At this point, it is widened by removal of more bone anteriorly and posteriorly over its lower third (Fig. 18.12). In effect, this widening provides the necessary window for good exposure of the middle-cranial-fossa floor, while the relatively limited superior slot affords a secure location for the middle-fossa retractor. Using theoperating microscope, thedura is then elevated, starting from behind, working anteriorly and progressively deeper. Adequate exposure of the middlefossa floor is fundamental to the success of this procedure. Time taken elevating the dura is well spent and cannot be considered complete until the petrous ridge andsuperiorpetrosal sinus have been reached. To achieve this, some use a malleable retractor to lift the dura while dissecting with a dural elevator; others favour the combination of a curved sucker and angled microraspatory.Oftennumerousminor blood-vessels areencounteredrunning between the dura and bony floor. Each should be very carefully coagulated; otherwise, if torn, they bleed furiously, are difficult to control and hamper the dissection. Bleeding from the floor can usually be controlled by either bone wax or obliteration

Fig. 18.12 Middle cranial fossa approach. Extent of the craniotomy with widening o f the inferior section.

of the vascular channel by runningadiamond-paste burr over it without irrigation. As the dissection proceeds, dural tension limits medial access. This can be overcome either by releasing CSF throughthespinal drain or directly through a minipuncture of the temporal dura. The middle-fossa retractor is inserted once the surgeon has elevated the dura. The blade is positioned and angulated to give a generous and unimpeded view of the meatal plane, a flat area immediately anterior to the arcuate eminence, under which lies the IAC (Fig. 18.13). The meatal plane is then reduced with a diamondpaste burr, accompanied by suction irrigation. It is best to identify the superior semicircular canal first by 'bluelining' it alongits entire length. This serves as acheck on position for the operator and helps define the precise location of the IAC, which lies withina 60" angle, anterior to the superior semicircular canal, subtended from its ampulla.The bone overlying the IAC is of variable thickness and, despite hours of training in the temporal-bone laboratory, itis easy to lose confidence at this point in the operation or become frankly disorientated. If this shouldhappen,it is wise to openthe tegmen of the middle ear and identify the malleus head, body of the incus, tympanic segment of the facial nerve and both lateral and superior semicircular canals: far better this than accidentally damage the geniculate ganglion. Eventually, the outline of the canal will emerge. The entire canal, from the vertical crest laterally to the porus medially, should be exposed over as large a cir-

Fig. 18.13 Transtemporal middle fossa approach. Retractor in position exposing the floor of the fossa and the meatal plane.

Fig. 18.14 Middle cranial fossa approach. Exposure of the internal auditory meatus from the vertical crestto the porus.

cumference as possible, withoutdamagingthe facial nerve (Fig. 18.14). The dura of the IAC is incised along its entire length to expose the superior vestibular nerve. This is sectioned distally with a neurotomy knife. By using the microsuctionasa gentle retractor,the superior vestibular nerve can be elevated and peeled medially to uncover the inferior vestibular and singular nerves in the depths of the canal. These nerves can then be sectioned and the

Surgery forVertigo

13 3

rarely a problem and can be achieved with codeine, 3060mg, or non-opioid agents. Most develop a slight degree of facial weakness, which is often delayed and should only be transient. Patients cannot drive until they have been assessed as safe to do so at a subsequent follow-up appointment, which is usually 6 weeks later. Complications

Fig. 18.15 Middle cranial fossa approach. Superior vestibular nerve has been divided, exposing the inferior vestibular nerve.

entire vestibular nerve, complete with Scarpa’s ganglion, is gently and gradually lifted out of the canal, cutting the vestibulofacial anastomosis of Rasmussen in the process. The nerve is sectioned proximal to the ganglion (Fig. 18.15). Closure

A free muscle graft is taken from the temporalismuscle and used to seal the IAC, stabilised if necessary with fibrin glue. The tegmen is reconstructed with bone from the craniotomy. This helps to prevent subsequent prolapse of the dura and consequent conductive hearing loss. The bone is placed like a lintel, covered by the pedicled temporalis-muscle flap and held in place by both fibrin glue and pressure of the dura. Residual bone from the craniotomy is then replaced but does not need to be wired or plated in position. The woundis closed in layers over a fine suctiondrainwith 3/0 Vicryl and staples. Postoperative management

If a lumbar drain has been used, the patient is kept flat for the first 48 h, with the CSF pressure kept between 0 and 2cmH20. Itcan be closed and subsequently removed if there is no sign of CSF in the vacuum drain. Similarly, the vacuum drain is removed when less than 15ml of exudate accumulates in any 24 h period. After careful mobilisation, the patient is usually fit for discharge after the staples have been removed on the fifth postoperative day. Pain relief throughout this period is

Recognised complications include sensorineural and conductive hearing losses, facial weakness, CSF leaks and extraduralhaematoma. In experienced hands, complication rates are very small indeed. In a series of 650 cases Fisch & Mattox (1988) reported increased sensorineural hearing loss and temporary facial weakextradural ness in 3%, transient CSF leaks in 6% and an haematoma in one patient.

Endolymphatic-sac decompression and drainage This procedure remains at the centre of the controversy about the surgical treatment of Menikre’s disease, the only condition for which it is advocated. As mentioned earlier, its advocatesremain convinced of theoperation’s efficacy (Portmann, 1969; Arenberg, 1987), but the naturalhistory of the disease precludes incontrovertible and statistically sound evidence tosupport their case. In the light of this difficulty, it is perhapsnot suprising that the clinical outcome is similar for both shunting and decompression of the sac. Preparation

Fully informed consent is essential, although this probably stops short of discussing the possible placebo effect of the procedure. Patientsshould begiven a realistic assessment of their prognosis. Unlike neurectomy, acquired sensorineural hearing loss and facial-nerve dysfunction are most uncommon. No special preparation for surgery is necessary, other than that required for a routine mastoid exploration. Prophylactic antibioticsarenot given. Facial-nerve monitoring is prudent and hypotensive anaesthesia aids vision. Incision

A standard retroauricular

incision is employed, identical to that which would be used foracortical mastoidectomy.

I 34

Chapter 18

A very thorough simple mastoidectomy is performed in which the vertical segment of the facial nerve, posterior semicircular canal,lateralsinusandjugularbulbare clearly defined. The retrofacialair cells areopened widely, as it is in this region that the sac will be found. Using a large diamond-paste burr, the duraimmediately anterior to the lateral sinus is exposed. The remaining posterior-fossa dura, between the lateral sinus and the posterior semicircular canal, is then gently separated fromthe overlyingbony platewithacottonoid and blunt dissector, following which the bone itselfis removed (see Fig. 18.6). The sac is then identified and, to facilitate this, various methods have been advocated. In the authors’ experience, the most consistent guideis the colour of the dura, thesac being whiter than theadjacent dura, which appears slightly bluish. There is also frequently a small blood-vessel, which runs longitudinally along the sac. Others suggest identifying thevestibularaqueduct, through which the sac and ductpass. This can be determined, almost blindly, by blunt dissection of the dura medial to the posterior semicircular canal and feeling resistance to dissection at the pointwhere the sac enters the aqueduct. Once defined, bone surrounding the sacis removed, so that,at the very least, it is thoroughly ‘decompressed’. The sac is then opened with either a Beaver blade or a sickle knife and thewalls of the sac are defined. Surgeons tend to express individual preferences for shunts. Several designs are available commercially, none of which can justifiably claim to be superior in any respect. Many find that a small piece of Silastic sheeting, cut to size, is perfectly adequate and considerably less expensive. The shunt is stabilised by a small piece of absorbable sponge.

The mastoid cavity is closed in layers with 3/0 Vicryl and 4/0 Dermalon sutures without a drain. A standard mastoid head bandage is then applied.

The most important complications reported after this procedure are labyrinthine fistula and CSF leak. Labyrinthine fistulae are almost always in the posterior semicircular canal and can be avoided by not blue-lining it. CSF fistulae are best prevented by thorough inspection of the dura and reinforcement of any suspect area with free muscle grafts before closure of thewound.The most likely site of damage is in the proximity of the sac, perhaps caused by incision through it.

Labyrinthectomy remains the initial procedure of choice for patients with no useful hearing on the affected side andnormalhearing in theirotherear.Properlyperformed,thisoperation is effective and considerably easier to undertakethantheothers described in this chapter .

The patient must be aware that, for some weeks after surgery, they mayexperience instability,particularly with rapid head movements. Most compensate for loss of vestibular activity within 3-6 months but few ever return to normal. No special preparation for surgery is necessary, other than that required for a routine mastoid exploration, and prophylactic antibiotics are notgiven. Facial-nerve monitoring is prudent and hypotensive anaesthesia aids surgical vision.

A standard retroauricular incision is employed, identical tothat which would be used for cortical a mastoidectomy.

A simple, cortical,mastoidectomy is performed,in which the vertical segment of the facial nerve and all three semicircular canals are identified and skeletonised. The canals are then sequentially drilled out, taking care notto damagethefacial nerve inadvertently ator The head bandage is taken off on the first postoperative aroundthe second genu. The useof diamond-paste day and the sutures can be removed after 5 days. Moof rotation such bilisation of the patient should not present any problem burrs, copious irrigation and a direction that if theburr‘ranon’ accidentally itwouldtravel and mostare fit to go home onthe first or second away from thefacial nerve are standardprecautions. An postoperative day. additional safeguard employed by many is to leave the anterolateral wall of the lateral semicircular canal in s i t u

Surgery for Vertigo as additional protection to the facial nerve and to adopt a similar policy to the wall of the posterior semicircular canal when uncovering its ampulla. Once the membranouscanal and threeampullae have been removed, the posterior aspect of the vestibule is opened and its contentsare evacuated. It is essential that everyvestige of neuroepithelium is removed; otherwise, viable remnants may subsequently giverise to spontaneous, aberrant, neural activity and continuation of troublesome vertigo.

I35

been described -for example, cochleosaculotomy (Schuknecht, 1982), tack operations (Cody & McDonald, 1983) occlusion of the posterior semicircularcanal(Parnes & McClure, 1990)and singular neurectomy(Gacek, 1974). Others will surely follow. Most have enjoyed a period of intense enthusiasm, only to fall fromfavour.Theprocedures described in this chapter have stood the test of time, even if not all have satisfied the statistician or cynic. The reader would be well advised to let others try new operations and not prescribe or attempt them until their efficacy has been proved by strictly controlled clinical trials.

A free muscle graft is placed in the empty vestibule. The mastoid cavity is closed in layers with 3/0 Vicryl and 410 Dermalonsutureswithoutadrain. A standard mastoid head bandage is then applied.

The head bandage is taken off on the first postoperative day and the sutures can be removed after 5 days. The patient is usually moderately vertiginous on regaining consciousness and almost always exhibits some degree of spontaneous nystagmus. This subsides slowly over a few days but leaves the patient very unsteady for some weeks. Patients require some assistance to regain their mobility, and regular vestibular sedative medications, for example, prochlorperazine Smg,C;-hourly, ishelpful and may be needed, in lowering dosage, for several weeks. Discharge from hospital will be influenced by the patient's social arrangements but most are fit to return home within 4-5 days. Like other operations for vertigo, patients who have had a labyrinthectomy should not drive until they have been free fromattacks of spontaneous vertigo for at least 3 months and can make rapid head movements without precipitating a sensation of unsteadiness.

The only complications of noteare facial palsy and persistent vertigo. Consummate care in operative technique, togetherwith facial-nerve monitoring,should prevent the former. Continuing vertigo may reflect incomplete removal of sensory neuroepithelium, but may also indicate that there is a contralateral lesion which had evaded detection or developed subsequently.

Other procedures for the management

of vertigo have

Alford BR (1972) Report of subcommittee on equilibrium and its measurement: Menilre's disease. Trans. Am. Acad. Ophthalmol. Otolaryngol. 76, 1462-4. Anson BJ & Donaldson JA (1981a) The temporal bone. In: Surgical Anatomy of the Temporal Bone. Philadelphia, W.B. Saunders, p. 11. Anson BJ & Donaldson JA (1981 b) The internal ear. In: Surgical Anatomy of the Temporal Bone. Philadelphia, W.B. Saunders, p. 298. Arenberg IK (1987) Results of endolymphatic sac to mastoid shunt surgery for Menilre's disease refractory to medical therapy. Am..] Otol. 8 , 33.5-44. Arenberg IK,Jackson CG, Gardner G et al. (1987) Panel discussion: the surgical anatomy and fine points of endolymphatic system surgery. Am. .] Otol. 8 , 34.5-54. Atkinson WJ (1949) Theanterior inferior cerebellar artery. J.Neurol. Neurosurg. Psychiatry 12, 137-51. Balkany TJ, Sires B & Arenberg IK (1980) Bilateral aspects of Menilre's disease: an underestimated clinical entity. Otolaryngol. Clin. North Am. 13, 603-10. Catalano PJ & Eden AR (1993) An external reference to identify the internal auditory canal in middle fossa surgery. Otolaryngol. Head Neck Surg. 108, 111-16. Cody DTR & McDonald TJ (1983) Tack operation for idiopathic endolymphatic hydrops: an update. Laryngoscope 93, 1416-24. Dornb GH & Chole RA (1980) Anatomical studies of the posterior petrousapexwith regard to hearing preservation in acoustic neuroma removal. Laryngoscope 90, 1769-76. Espir M & Godwin-Austen RB (1978) Disorders of the nervous system. In: Raffle A (ed.) Medical Aspects of Fitness to Drive-a Guide for Medical Practitioners. London: Medical Commission on Accident Prevention, 26-9. Fisch U (1970) Transtemporal surgery of the internal auditory canal. Adv. Otorhinolaryngol. 17, 202-39. Fisch U & Mattox D (1988) In: Microsurgery of the Skull Base. Stuttgart & New York, Georg Thieme Verlag, p. 419. Friberg U, Jansson B, Rask-Andersen H & Bagger-Sjoback D (1988) Variations in surgical anatomy of theendolymphatic sac. Arch. Otolaryngol. Head Neck Surg. 14, 389-94. Gacek RR (1974) Transection of the posterior anlpullarynerve for the relief of benign positional vertigo. Ann. Otol.Rhinol. Laryngol. 83, 596-60.5. Glasscock h4 (1969) Middle fossa approach to the temporal bone. Arch. Otolaryngol. 90, 41-57.

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Chapter 18

Haye R & Quist-Hanssen S (1976) The natural course of Meniitre’s disease. Acta Otolaryngol. 82, 289-93. House WF (1961) Surgical exposure to the internal auditory canaland its contents through the middle cranial fossa. Laryngoscope 71, 1363-8.5. Kartush JM, Kemink JL & Graham MD (1985) The arcuate eminence: topographic orientation in middle cranial fossa surgery. Ann. Otol. Rhinol. Laryngol. 94, 2.5-8. Kartush JM, Telian SA, Graham MD & Kernink JL (1986)Anatomic basis for labyrinthine preservation during posterior fossa acoustic tumor surgery. Laryngoscope 96, 1024-8. Laine T, Johnsson L-G & Palva T (1990) Surgical anatomy o f the internal auditory canal. Acta Otolaryngol. (Stockh.) 110, 7884. McKenna MJ, Nadol JB, Ojernann RG & Halpin C (1996) Vestibular neurectomy: retrosigmoid-intracanalicular versus retrolabyrinthine approach. Am. J. Otol. 17, 2.53-8. Parisier S (1977) The middle cranial fossa approach to the internal auditory canal. Laryngoscope 87 (Suppl. 4, Part 2), 1-20. Parnes L & McClure JA (1990) Posterior semicircular canal occlusion forintractable benign paroxysmal vertigo. Ann.Otol. Rhinol. Laryngol. 99, 330-4. Portmann G (1969) Surgical treatment of vertigo by opening of the

saccus endolymphaticus. Arch. Otolaryngol. 89, 31-7. Roland PS, Meyerhoff WL, Wright CG & Mickey B (1988) Anatomic considerations in the posterior approach to the internal auditory canal. Ann. Otol. Rhinol. Laryngol. 97, 621-S. Sanna M,Saleh E, Russo A & Taibah A (199.5) In: Atlas of Temporal Stuttgart & New York, Georg Bone and Lateral Skull Base Surgery. Thieme Verlag, p. 90. Schuknecht HF(1982) Cochleosacculotorny for MeniGre’s disease: theory, technique and results. Laryngoscope 92, 8.53-8. Silverstein H, Norrel H & Smouha EE (1987) Retrosigmoidinternal auditorycanal approach vs retrolabyrinthine approach for vestibular neurectomy. Otolaryngol. Head Neck Surg. 97,3007. Silverstein H, Norrell H, Smouha E & Haberkamp T (1988) The singular canal: a valuable landmark in surgery of the internal auditory canal. Otolaryngol. Head Neck Surg. 98, 138-43. Silverstein H, NorrellH & Rosenberg S (1990)The resurrection of vestibular neurectomy: a 10 year experience with 115 cases. 7. Neurosurg. 72, 533-9. Silverstein H, Wanarnaker H, Flanzer J & Rosenberg S (1 992)Vestibular neurectomy in the United States- 1990. Am. J. OtoE. 13,2330. Wallenburg A (1901) Dtsch. Z. Nervenheilk. 19, 227.

TRISTRAM H.J. LESSER

preoperative planning session needs to take into account all the clinical and radiological information in order to decide on the exact approach and which variations are to be used. All members of the skull-base teain shouldbe involved in thepreoperativeplanning.Apure-tone audiogram (PTA) is important if any hearing is to be risked and, if there is any doubtasto the level of hearing, further audiometry is done. It is also important to introduce the patient to the rehabilitation team preoperatively: the physiotherapist, who will be doingthe vestibular training and facialnerve exercises, the speech therapist, who will be helping rehabilitate swallowing, and the nursing staff on the ward.

1 To approach and remove tumours of the lateral skull base, e.g. glomus jugulare tumours. 2 To provide access to intracranialstructures and tumoursatthe base of thebrain, e.g. petroclival meningiomas. 3 To remove malignant tumours invading the skull base from below, e.g. parotid cancers.

Given these indications forusing the infratemporalfossa approach, it is obvious that it is not a single operation but an approach in general that is described. There are a number of steps that are common to almost all the operationsdonebut each one is unique and planned specifically for the tumour and patient. A full and accurate assessment of the extent of the tumour, using both CT and MM, is essential. This is complemented by radiological assessment of the vessels of the skull, depending on the site of the tumour and its blood supply. If any vessels are at risk of being sacrificed, full bilateral carotid and vertebral angiography is done, with assessment of the collateral circulation.If the internal carotid is at risk, a trial balloonocclusion of the carotid is performed and the patient assessed clinically for neurological deficit prior to leaving the balloon in situ. Venous angiography is needed to show cross-flow between the two sides and may demonstrate intravenous turnour. If the tumour is vascular, preoperative embolisation is performed, if technically feasible. This should be done within a few days of the surgery. On occasion, it may be necessary todo more thanone embolisation to ensure maximal devascularisation. The

Relevant anatomy Strictly speaking, the infratemporal fossa is the space limited anteriorly by the posterior aspect of the maxilla and inferior orbital fissure and posteriorly by the tympanic and mastoid partsof the temporal bone. The roof of the fossa is formed by the lower surfaces of the greater wing of sphenoid andsquamouspart of the temporal bone. The medial limit is the spine and pterygoid process of the sphenoid, the lateral portionof the clivus and the lower surface of the petrous apex. The lateral limit is the zygomatic arch. The infratemporal fossa approach is rather more than the surgery of thisarea and really developed from translabyrinthine and transcochlear approaches for acoustic neuroma surgery. These were extended into the infratemporal fossa by Ugo Fisch in the 1970s. Since thentheinfratemporalapproachhas included the temporal-bone surgery as well as thesurgery of the fossa itself and its surrounds. Indeed, it has become a generic '37

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term for surgery of the lateral skull base. The infratemporal fossa approaches were named by Fisch A, B and C, followed later by a preauricular approach D (see Fig. 19.9). Theanatomy of lateral skull-base surgery is most easily understood from the temporalbone outwards and in particular from the course of the facial nerve. The facial nerve crosses from the brainstem into the internal auditorymeatus (MM) and along it. In doing so, it rotates from an inferior to anterosuperior relationship with the eighth nerves. It forms a sharp angle at the geniculate ganglion, where the superior petrosal nerve leaves to pass forwards along the floor of the middle fossa. The facial nerve itself runs posteriorly, asthe horizontal segment through the middle ear with its propensity to be exposed. There are a great many variations in the angle and curve of the second genu as it goes inferiorly intothe vertical mastoid segment. Furthermore the angles and depth at which it exits from the stylomastoid foramen and the variety of branching in the parotid vary enormously. The anatomy of the jugular foramen is another challenge for the infratemporal fossa surgeon. The jugular bulb is separated, when approachedlaterally, by a dense fibrous band,continuousanteriorlywiththecarotid sheath. Deep to this is the carotid plate, separating the two vessels, and deep to this is the parsnervosa, with the jugular nerves. TheIXth nerve is anterolateral and the N t h posteromedial.The inferior petrosal sinus flows into thebulb through the parsnervosa, there being no distinct compartment between thepars nervosa

and pars venosa. The sigmoid sinus lies lateral to the jugular bulb, entering its posterolateral margin. The hypoglossal nerve has a separate foramen posteromedial to the jugular foramen.Theinternalcarotid is most easily identified in themedial wall of the otic entranceto the Eustachian tube. Its anatomy and any variations are easily identified from the preoperative angiogram. Figure 19.1 shows the general relations of the lateral skull base.

The patient is operated on either supine or in the parkbench position, with thehead turned 4.0-60" away from the side of the lesion so that themastoid surface is parallel to the floor. The supine position is most useful if the neck needs exploring and the park-bench more useful if the exposure may need extending into theback of the head. Skull fixation can be used in either position, but the author tends to use it mainly in the park-bench position, when cerebellar retraction is going to be required. It is mandatory when the intraoperativeviewing wand is being used to identify the anatomy and pathology of the skull base, as, once thepatienthas been registered on the computer with the MRI and CT scan information, the arm of the wand requires a fixed connection to the skull. incision

A large C-shaped incision is made, curling around the back of the ear, with anextension down the neck just in front of the sternomastoid. The anterior superior extent of the incision is 1 inch (2.5cm) aboveand 1 inch (2.5cm) anterior to the superior marginof the ear canal. Care is taken not to damage the frontal branch of the facial nerve here. The posterior curve of the incision is far enough back to allow easy control of the sigmoid venous sinus (Fig. 19.2). Procedure in sta

Closure of the ear canal

Fig. 19.1 General relations of the lateral skull base.

The flap is raised, including the pinna, the external canal is divided and sutured and the superficial parotid fascia exposed. The methodof suturing the ear canalis important and if not carefully done will allow cerebrospinal fluid (CSF) leaks in theshorttermorimplantation dermoids in the long term. If the ear canal was previ-

Approaches to the ~ n f r a t e ~ p o rFossa al

I 39

through the ear canal using an inferior and superior stay suture to bring it to the outside. The cuff of skin is then sutured closed using a J-shaped needle and Dexon 3/0 (Fig. 19.3). If the ear canal has already had a previous operation, e.g. meatoplasty, a more complicatedclosure is required. The skin of the anterior canalwall is used as a flap to close the ear canal. Theskin is cut anteriorly in the ear canal at the junction of the bony and cartilage parts and then dissected laterally to elevate it off the anterior canal wall, so that it becomes based on the tragus. The posterior canal skin is totally removed and with it some of the skin of the concha. The flap is then sutured on to this conchal surface. Whichever closure is used, all the remaining skin of theearcanal and eardrum must be removed to avoid animplantation cholesteatoma. It is best to remove this skin under the microscope and to take in it onepiece with the tympanic annulus. Exposure of the facial nerve Fig. 19.2 Large C-shaped incision curling around the back of the ear, with an extension down the neck in front of the sternomastoid.

The superficial parotid is exposed and the exit of the facial nerve from the stylomastoid foramen found (in some cases the nerve has to be traced proximally from a distal branch, e.g. in malignant tumours). A superficial parotidectomy is done far enough to expose the branches of the facial nerve. The extentof the superficial exposure becomes apparent, with the zygoma and frontalbranch and thetemporalis muscle superiorly, the muscles over the mastoid and suboccipital areas posteriorly andthe superficial muscles of the neck inferiorly. Neck dissection

Fig. 19.3 (a) Eversion and (b) closure of ear-canal cuff.

ously intact,it is divided at thejunction of the cartilaginous and bony parts. Then, from the inside to out, it is dissected for 1cm laterally to form a cuff of skin which is free of the cartilage. This cuff is everted

The neck is then dissected to identify and control the internal (ICA) and external carotid arteries (ECA) and, if required,any feeding vessels are tied off, e.g. the ascending pharyngeal or occipital arteries. The internal jugular vein (IJV) is also controlled and then the jugular nerves identified so they can be dissected up into the skull base. The posterior belly of the digastric muscle is removed from the temporal bone and further soft-tissue dissection done of the IJV, glossopharyngeal, vagus, accessory and hypoglossal nerves and the ICA as they pass between neck and skull base (Fig. 19.4). Flap retraction At this point the flaps are held down, usually with fishhooks and elastic bands, but, if the head frame is being used, with hooks attached to the frame.

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Fig. 19.5 V-shaped osteotomy of zygoma.

Fig. 19.4 Neck dissection of vein, arteries and nerves.

one exposure

Muscle is then removed from the underlying bone, the amount depending on the exact area of interest. The sternomastoid muscle is removed fromthemastoid process. The temporalis muscle is elevated and reflected anteriorly or inferiorly. When this is reflected inferiorly, the zygoma is mobilised and reflected inferiorly. This is required whenanteriorextensionfromthetemporal bone is desired. To do this, an anteriorly facing Vshaped bone cut is made as far anteriorly as possible and the arch of the zygoma freed posteriorly and then reflected inferiorly but still attached to the masseter inferiorly (Fig. 19.5). If the zygoma is not removed, the bulk of the temporalis muscle is in the way. The zygoma is repaired at the end of theoperation, either with miniplate fixation or with wire. Initial bone removal

If it is possible to remove any areas of the skull intact so that they can be replaced as free bone, then this is done; otherwise thebone is removed with the drill. A complete mastoidectomy is done. All mastoidair cells are removed, thesinodural angle exposed,themastoid antrumopened and the digastric ridge exposed. The

digastric ridge is followed forwards to the stylomastoid foramen, finding the mastoid segment of facial nerve between this andthe lateral semicircular canal.The sigmoid sinus is completely exposed, the mastoid emissary veins need care and are best dissected out with the drill and bipolar-coagulated for somelength. The transverse sinus is often exposed also, as this may be needed to allow control of the sigmoid. The sigmoid sinus is followed to the jugular bulb. When the vein is to be sacrificed, it is important toavoid blocking Labbk’s vein when obliterating the transverse sinus. This is possible to do when using muscle plug for obliteration of the vein. The sigmoid sinus can almostalways be sacrificed, but the reassurance of venous angiography to demonstrate whether there is normal bilateral drainage is essential (theauthor hashad two cases where it was absent). Thebone of the floor of the middle fossa is also drilled away, to expose the superior petrosalsinus. If the labyrinth is to be saved, it is not opened, and the semicircular canals are exposed and outlined. Transposition of the facial nerve-if required

The middle ear is removed, with malleus, incus and stapes arch. The facial nerve is then completely skeletonised, from geniculate ganglion to stylomastoid foramen. Depending on the access needed, i.e. to the jugular foramen or the lower part of the clivus, the facial nerve has to be moved out of the way. This is done by drilling a groovein the remnant of the anterior atticwall between the geniculate ganglion and theroot of the zygoma. The facial nerve is carefully mobilised from the stylomastoidforamen to the geniculate ganglion and reflected forwards. Some further elevation in the parotid is needed. It is then glued forwards with fibrin glue (Fig. 19.6). The horizontal segment of the nerve is easy to

Approaches to the ~ n ~ r a t e ~ p oFossa ral

141

top of the jugular bulb is sometimes very close to the meatus. The IAM is anterior to the horizontal part of the facial nerve in the middle ear and it is medial to the vestibule and runs into the posterior fossa in approximately a straight line with the external meatus. Jugular fossa dissection

Following obliteration of the sigmoid sinus and tying the IJV, dissection of the jugular foramen is undertaken. The nerves are very difficult to dissect from surrounding structures and are often damaged here. When the jugularforamenhas been opened,the bleeding fromthe inferior petrosal veins requires packing and this indirect pressure on the pars nervosa can also injure nerves IX and X (Fig. 19.7).

Fig. 19.6 Anterior transposition of cranial nerve VII.

mobilise, but the genu and vertical segment need sharp dissection from the branch to stapedius, together with vessels that come in on the deep surface. It is also very difficult to separate the nerve out at the stylomastoid foramen, so the author takes it up with all the softtissue of the foramen surroundingit. In doing so, the nerves to digastric and stylohyoid are cut.Occasionally, for access to the pons, it has been necessary to move the nerve posteriorly by cuttingthe greater superficial petrosal nerve and,after dissecting out the IAM, reflecting it posteriorly. If less superior access is required, just the parotid, stylomastoid foramen and mastoid parts of the facial nerve can be mobilised, the jugular fossa being approached from below in a transcervical transmastoid direction. ~abyrinthectomy -if required

The remnant of the otic capsule is then removed. It is nice to do this methodically, but it is as easy to drill straightthrough it to the IAM. Thehorizontal and posterior Semicircular canalsareopened and drilled away. The superior semicircular canal is then encountered, with the subarcuate artery bleeding in the centre of the semicircle. The vestibule is then opened and the IAMfoundand skeletonised. It is best towork all around the meatus before opening it, in order to avoid injury to the nerves and to operate without CSF flowing. It is surprising howmuch bone has to be removed above and below the meatus to get around it. Inferiorly, the

The internal carotid artery and temporomandibular joint

The carotid canbe mobilised by first removing the basal turn of the cochlea and tensor tympani muscle. Exposure is then obtained by drilling away the bone posterior and superior to the temporomandibular joint (TMJ). The joint is then mobilised and either retracted downwards with a sharp hook or thecondyle removed and a large self-retaining retractor inserted, great care being taken to avoid puttingundue pressure on the facial nerve. The infratemporal fossa itself

The bone of the floor of the middle cranial fossa is removed to gain initial access. Minimal extradural retraction of thetemporal lobe is requiredduringthis drilling. The author finds this exposure is best done by following the ICA inwards and then drilling away from this. The middle meningeal artery has to be coagulated and the mandibular branch of the trigeminal nerve sacrificed for anterior exposure. There is often about 1cm of exposure that is gained just from the bony removal without any retraction at all. When starting this part of the dissection, it looksasthoughthere will not be enough space but it opens up. The Eustachian tube is removed in this process, at least to the isthmus, and the pterygoid process anteriorly can also be removed. For full exposure, the maxillary as well as the mandibular branch of the trigeminal nerve must be exposed and may need to be sacrificed. Exposure is thus obtained of the cavernous sinus and intracavernous carotid, the upper clivus or parasellar region or the nasopharynx via the infratemporal fossa (Figs 19.7 and 19.8).

Fig. 19.7 Posterior extent of exposure.

Tumour removal

It goes without saying that having taken the trouble to obtain thenecessary exposure there canbe no relaxation about the subsequent tumour removal. For malignant tumours, the aim is en‘ bloc removal.Forbenign tumours, piecemeal removal is undertaken, with every bit of tumour being removed. The type of tumour dictates the extent to which this is done, e.g. glomus tumours require free flow from all the vessels before theyare obliterated to wash out any fingers of tumour and drilling away all bone to clean white cortex, orrecurrence is possible. Epidermoids require removal of all matrix, or recurrence is likely,

TheEustachiantubemust be carefully obliterated to avoid CSF rhinorrhoea. This is done by removing bone (if it has not already gone) as far as the cartilaginous part and making sure there is no mucosa left. The isthmus is then diathermised, filled with impacted bone dust

and then muscle and covered with fibrin glue. If the dissection hasgone all the way into the sphenoid or nasopharynx,suturesshouldalso be used, but these need backing up with vascularised tissue. Whenthedurahas been opened every attempt is made to close it and place as many layers between it and the skin. This usually means overfilling the cavity with free abdominal fat and closing the muscle layers over it. If theinfratemporal fossa has been opened, the temporalis muscle should be folded in to obliterate this. If skin or nasopharynx is missing, a vascularised free flap is used. This is done by a separate team andusually a rectus abdominis or latissimus dorsi flap is used. The skin is closed in layers, drains being used when surgically appropriate. A pressure dressing is routinely applied for 5 days.

If there is a significant risk of a CSF leak, a lumbar drain is used for 3-5 days. Antibiotics are routinelygiven. The patient is carefully monitored on the ward for 48 h. A

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Fig. 19.8 Anterior extent of exposure,

tracheostomy is not usually required, but a nasogastric tube is left in situ untilthe gag reflexis checked. If aspiration is suspected, a videofluoroscopy swallow is doneand if no manoeuvres avoid aspirationa percutanous endoscopic gastrostomy (PEG) is inserted and usually kept for many. months. If the vagus has been damaged, a thyroplasty (type 1) or Teflon injection is done, dependingon the age of the patientand prognosis.

Complications Cranial nerves

The facial nerve is at great risk of traumatic injury in these procedures. If the nerve is normal prior to the surgery and the tumourresection does not require sacrifice of the nerve or its epineurium, the recovery is usually House grade 1 or 2, even if the nerve is permanently reflected forwards. If the nerve is not moved, it remains normal. If the nerve is moved posteriorly, then at best House grade 3 or 4 results. If the nerve is cut, it must be anastomosed at that procedure, since the delayed

hypoglossal facial anastomosis may not be an option as the hypoglossal nerve may have also been damaged. The injury to jugular nerves is discussed above in the postoperative swallowing and speech care.

These are more serious and cause both immediate lifethreatening problems and long-term morbidity. Postoperative pneumocephalus may occur when the dura has been breached, and this causes the patient to have decreasing responsiveness. An urgent CT scan will show this and differentiate it from cerebral oedema or intracranial haemorrhage, which may need urgent intervention. The vascular complications are very serious and may leave the patient dead or with a stroke. Cerebellar herniation may also occur later in the convalescent period. These complications arenot exclusive to intradural procedures. CSF fistula remainsthe bane of skull-base surgery when the dura is breached. It is best avoided if possible, but if it occurs will often need further procedures, with

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repeat lumbar drainage and occasionally even shunting to avoid the risks of meningitis. Pseudomeningoceles occur and may troublethepatientandas much as possible these should be avoided.

Alternative procedures and classification The above description is of lateral approaches to the skull base and includes a distillation of all the surgery going through the temporalbone. As stated above, these have been classified byUgo Fisch (Fig. 19.9). Type A has anterior transposition of nerve VI1 as its distinguishing feature, without zygomatic displacement Type B has the facial nerve left in situ and the zygoma reflected inferiorly, with the frontal branch of the nerve protected by the temporalis muscle and the bone of the middle fossa removed for exposure of the infratemporal fossa. The mandibular branch of cranial nerve V and the middle meningeal artery are sacrified. Type C is the logical anterior extension of this, with skeletonisation of the maxillary branch of the trigeminal nerve and resection of the pterygoid plates for exposureof the nasopharynx. Type D differs from the other three approaches in that the skin incision is preauricular and can only provide anterior exposure. In it the zygoma is retracted, with the lateral orbital rim and the carotid foundand followed as before. It is possible to use any variation and give it another name, e.g. subtemporal anterior transpetrosal approach. There are, however, some angles which approach the same areas with less extensive temporal-bone surgery, e.g. the jugular bulb can be approached by atranscervical transmastoid approach. The anteriorpart of the lateral skull base can be approached by a lateral facial approach, also referred to as a temporozygomatic ap-

Fig. 19.9 Fisch types A, B, C and D.

proach. Such approaches can involve lateral facial disassembly, with consequent sacrifice of facial-nerve branches and reanastomosis. The posterior part of the region can be approached via the posterior fossa and can be approached posteroinferiorly by the far-lateral approach.

Further reading Fisch U & Mattox D (1988) Microsurgery of the Skull Base. New York, Thierne. Sekhar LN & Janecka IP (1993) Surgery of Cranial Base Tumors. New York, Raven Press.

lomus CHRIS A. M I L F O R D

Indications

Contraindieations

The intricate temporal-bone anatomy, the extent of tumour invasion and the tumour vascularity combine to make glomus tumours of the temporal bone difficult to manage by anymode of therapy. As a result of the difficulties posed by this normally benign tumour, treatment is still controversial. The critical question to be asked is whether the disease is likely to cause the patient serious problems in the natural course of hislher remaining years. At one end of thespectrumalarge tumour in ayoung, fit patient almost certainly warrants surgical treatment, whereas asmall tumour in an elderly patientprobably needs nothing more than careful review. Unfortunately, there is a large grey area between these two ends of the spectrum. Surgerymayhave to be considered in the management of largeglomustumours since othertreatment modalities are not curative. The judicious use of surgical intervention is imperative since aneurological deficit involving thelastfourcranial nerves may ensue andconsideration of thequality oflifeof the patient in thepostoperativeperiod isof paramount importance. Approximately 10% of these patients will have muftiple lesions. When they are bilateral, the risk of dealing withboth lesions liesin the possibility of bilateral denervation of thelarynxandhypopharynxandthe resultant laryngotracheal aspiration. In this situation it may be appropriate to deal only with the largerlesion if it warrants surgery, using other treatment modalities(or no treatment) for the contralateral lesion.

1 Carotid involvement -internalcarotidartery(ICA) involvement with poor collateral cerebral circulation. 2 Contralateral vaguslesion-surgery whichcompromises the only functional vagus is contraindicated. 3 Unresectable tumour-a neurosurgically unresectable intracranial extension is a relative contraindication. 4 Anomalousvenousdrainage-where all intracranial venous return occurs via a single sigmoid sinudinternal jugular vein (IJV) on the involved side. In this situation itmay be better to awaitcomplete occlusion of the jugular bulb (which allows slow progressive opening of collateral venous channels) before operating.

Preoperative management The clinical picture of glomus tumoursis usually characteristic but the clinical findings alone are not adequate. The mainstay of tumour diagnosis is radiological and the main diagnostic objectives are as follows: 1 exclude catecholaminesecretionfroma vasoactive tumour; 2 determine the site and extent of the tumour; 3 determine the presence of synchronous lesions; 4 determine the degree of major vascular involvement; 5 identify intracranial extension; 6 determinecentralnervous system (CNS) collateral circulation. Urinary assay of themetabolites,dopamine and 3methoxy-4-hydroxymandelic acid (vanillylmandelic acid), is used to assess vasoactivity. Site and extent of the tumourmay be assessed by high-resolution CT scanning or MRI. It is critical to demonstrate if the jugular bulb is involved as thesugical implications areimmense.

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MRI is superior in assessing intracranialextension and is useful for identifying synchronous head and neck glomus tumours. Bilateral carotid angiography is used to determine ICA involvement in larger tumours andthe degree of collateral blood flow. It will also identify an aberrant ICAlintrapetrous carotid artery aneurysm (included in the differential diagnosis of a vascular lesion behind the tympanic membrane), aswell as the rarecase of anomalousvenousdrainage where all intracranial venous return occurs via a single sigmoid sinus/IJV on the involved side. If done preoperatively, it also allows embolisation of the lesion.

Themost widely used classification was devised by Oldring 8c Fisch. TypeATumours confined to the middle ear cleft (glomus tympanicum). Type B Tympanomastoid tumours with no destruction of bone in the infralabyrinthine compartment of the temporal bone. Type C Tumours invading the infralabyrinthine region and extending towards the petrous apex. Type I> Tumours with intracranial extension.

The jugular foramen is the bony opening through which the sigmoid sinus exits the skull to form the IJV. It is boundedanterolateraily by thetemporal bone and posteromedially by the occipital bone, the carotid artery within the carotid canal lying anterior and the facial nerve emerging at thestylomastoidforamen laterally (see Fig. 20.1). The jugular foramen is divided intotwocompartments (anteromedial and posterolateral) by a fibrous or bony ridge connecting the jugular spine of the petrous temporal bone to the jugular process of the occipital bone. The anteromedial part (pars nervosa) is occupied by the glossopharyngeal (IX)nerve and inferior petrosal sinus, and the posterolateral part (parsvascularis) by the vagus (X) and accessory (XI) nerves together with the jugular bulb. All three cranial nerves are in close proximity as they exit the skull base and are surrounded by fibrous connective tissue. Cranial nerve IX is the most anterior and runs forward over the ICA, XI is the most posterior and runs back superficial to the IJV, and X is themost medial as it runs inferiorly between the ICA and IJV (see Fig. 20.2).

Fig. 20.1 Relations of the jugular foramen at the

skull base.

Fig. 20.2 Contents of the jugular foramen and relation internal carotid artery.

to the

Several surgical techniques are available for removal of glomus tumours and these are dictated by the size and location of thetumour.The surgery forthose tumours not involving the jugular bulb (types A briefly, as these are and B) will be dealtwithonly

Surgery of Glomus Twnours of theTemporalBone

essentially approached techniques.

using

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standard otological

Type Postauricular transcanal approach

Althoughit is tempting to remove these tumours through a transcanal approach, they areoften bigger than expected and a postaural incision gives better exposure. A large tympanomeatal flap is raised posteriorly and reflected forward to give exposure of the middle ear and hypotympanum. A canalplasty can be performed if required to improve exposure. The tumour may be mobilised by dissecting with cotton-wool balls soaked in topical adrenaline (1:1000). If bleeding is brisk, control can be achieved with Surgicel packing. rs

Tympanomastoid approach with extended facial-recess dissection

Via postaural a incision, complete a simple mastoidectomy exposing all relevant anatomy is performed. The facial recess is entered and, by dividing the chorda tympani, the facial recess can be extended into the tympanic bone to visualise the hypotympanum and its contents (see Fig. 20.3). The medial landmark is the facial nerve, while the fibrous tympanic annulus provides lateral and anterior guides to allow for the clear exposure of thearea of thejugularbulb(shouldjugularbulb involvement be demonstrated intraoperatively, the procedure is stopped and skull-base exposure planned for a later date). Even better exposure is obtained by skeletonising the vertical portion of the facial nerve. The tympanic recess can thenbe opened widely medial to thevertical portion of the facial nerve, thus allowing access to the whole of the hypotympanum. Once all anatomy is identified, tumour removal can proceed.

The surgical objective is twofold: 1 total tumour removal in a single stage; 2 totaltumour removal preserving asmuchnormal anatomy and function as possible. In order to accomplish this, the approach must: 1 allow access to all tumour margins; 2 allow proximal and distal control of related major vascular and neural structures;

Fig. 20.3 Approach to tumour in the hypotympanum via the extended facial recess.

3 allow access to all margins of intracranial extensions. No single approach is suitable for all patients. Surgery must be tailored to individual cases based on tumour size and distal controlof the ICA. Necessary exposure of the ICA in thetympanic segment proximaltothe Eustachian tube“or in the intrapetrous portion distal to its tympanic genu determines the extent of the procedure:a basic transtemporal skull-base approach preserving ear anatomy or the infratemporal fossa approachwithexternalauditorycanal(EAC)overclosure (described by Fisch).

Preparation

Anaesthesia Anaesthetic management of patients undergoing resection of glomusjugularetumoursprimarilyconcerns close monitoring to alert the operative team of abrupt haemodynamic changes secondary to vagal manipulation. Special considerations arise when the turnour is a catecholamine ‘secretor’.

Position The patient is positioned supine with the head turnedto the contralateral side. The hemihead, ear and neck are

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prepared. Also prepared are the abdomen or thigh for harvesting of fat(and possibly fascia lata) grafts. A facial-nerve monitor is used if available. Basic transtemporal skull-base approach

For small- to medium-size glomus jugulare tumours limited to the jugular foramen and infralabyrinthine compartment, involving the ICA only in thetympanic segment or lower, thetranstemporal skull-base approach preserving the EAC and ear anatomy may be appropriate.Intracranialextension is not compatible with conductive-hearing preservation because the middle ear and Eustachian tube must be obliterated to prevent cerebrospinal (CSF) otorhinorrhoea. Lncision

A modified parotidectomy incision allows access to the temporal bone, neck and parotid area (see Fig. 20.4). Procedure

Dissection in theneck. The IJV and the common carotidartery(CCA), ICA and externalcarotidartery (ECA) are identified nearthecarotidbifurcation and secured with vascular slings, thus providing proximal

Fig. 20.4 Incision used for larger glomus jugulare tumours.

control of the major arterial structures and distal control of the IJV. Thesternomastoid muscle is disconnected fromthetip of themastoid process and the tumour identified in the neck along with the X (contained within the carotid sheath),XI (lying over the IJV before it enters the sternomastoid) andXI1 (as itcrosses the ECA just above the bifurcation) cranial nerves. Identification of cranialnerve VI1 intheparotid. The facial-nerve trunk is identified distal to the stylomastoid foramen in the usual manner (1cm medial and inferior to the tragal pointer,just above and medial to the insertion of the posterior belly of the digastric).The posterior belly of the digastric is released fr-om its attachment in the digastric groove (Fig. 20.5). Extensive cortical mastoidectomy. The soft tissues are elevated from the mastoid, extending from the mastoid tip to above the temporal line and from the zygomatic arch to 1cm posterior to the mastoid emissary vein. An extensive mastoidectomy is performed, skeletonising the Fallopian canal down to the digastric ridge, the dural plates of both the middle and posterior fossae and the sigmoid sinus. The mastoid antrum is identified. Access to the hypotympanum is obtained by the extended facial-recess approach, as described above. Removal of

Fig. 20.5 Dissection of the neck to expose appropriate structures.

Surgery of GlomusTumours of the TemporalBone

149

Fig. 20.6 Cortical mastoidectomy performed to show facial nerve.

the mastoid tip together with inferior tympanic bone and styloid process exposes cranial nerve VI1 in its canal from thesecond genu distally into the parotiddissection (see Fig. 20.6). Control of sigmoid sinus/ligation of IJV. Proximal control of the sigmoid sinus is achieved by intraluminal packing with Surgicel. As the sinus has had its bony covering removed, it is possible to occlude it above by applying pressure and then to open the sinus below the occlusion. Although some ‘back-bleeding’ occurs, it is possible to pack the lumen with Surgicel and hence ‘block’ the sinus. Using this technique, one avoids the need to incise dura to tie off the sinus and hence avoids the possibility of CSF leakage into the mastoid/ middle ear (with the resultant problem of CSF otorhinorrhoea if the middle eadtympanic membrane (TM) is preserved). The IJVis ligated, transfixed and divided in the neck.

‘Short’ mobilisation of facialnerve. Rarely, when the tumour isvery small, cranial nerve VI1 need not be disturbed and tumour removal can occur by working between the undisturbed VI1 and the lateral process of Cl. In most cases, however, VI1 must be mobilised. A ‘short’ mobilisation from the second genu up against the intact EAC permits exposure to the jugular foramen region (see Fig. 20.7). In mobilising the nerve at the stylomastoid foramen, the dense connective tissue surrounding the nerve is left on the nerve, as it may provide protection and help preserve some of its blood supply *

Distal control of ICA. Once mobilised, cranial nerve VI1 no longer precludes inferior tympanic-bone removal. Removal inferiorly, anteriorly and superiorly in extending thefacial recess will expose the openingof the Eustachian tube. Themedial wall of the Eustachian tube is removed (belowthe level of thecanalfortensor

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Chapter 20

Fig. 20.7 ‘Short’ mobilisation of facial nerve.

tympani) with a diamond burr and suction irrigation to expose the ICA distal to the tumour. Tumour removal. Once both proximal and distal control of the ICA is achieved, the tumour can be dissected from this vital structure unobstructed by VII. Once free of the ICAi the tumour is mobilised further andresected with the IJV and sigmoid sinus. Bleeding from the inferior petrosal sinus may be brisk and is controlled by packing it with Surgicel. Preservation of the lower cranial nerves within the pars nervosa region is tumoursize-dependent, i.e. if the tumourinvolves the nerves, the dissection is continued medially and will result in an increased neurological deficit postoperatively. Following tumour removal, VI1 can be replaced and any tympanoplastic work done if necessary. If there is any possibility of a CSF leak, then the mastoid cavity can be obliteratedwitha free fatgraft, which may also help restore the cosmetic deficit left by the bone removal.

Closure. The wound is closed in layers, using 3/0 catgut for the subcutaneous layer and 510 prolene for skin. A small suction drain is left in the neck and a standard mastoid pressure dressing applied for 24-48 h. Infratemporal-fossa approach For large glomus jugulare tumours extending beyond the temporal bone or involving the ICA above the tympanic segment, theinfratemporal-fossaapproachas described by Fischis required (see Fig. 20.8).The procedure sacrifices conductive hearing and normal lateral ear anatomy.

Incision An inverted 3-shaped incision is madeapproximately 5 cm posterior to the postauricular sulcus and extending into the upper neck (see Fig. 20.9).

Surgery

of

Glomus Tumours of the Temporal Bone

I 51

Procedure

Dissection in the neck. As above. Identification of cranial nerve VI1 in parotid. As above. Blind-sac closure of EAC. The EAC skin is dissected free ina sleeve medially and as close to theannulus as possible. It is then transected and the lateral canal skin is elevated fromthe underlying cartilage, everted asshownand sutured (see Fig. 20. loa-c). To ensure watertight a closure of the EAC, the development of a musculofascial flap helps create a second layer of closure under the closed everted skin of the EAC.

Fig. 20.8 Axial view showing extent of infratemporal fossa approaches (Fisch A and B).

Subtotal petrosectomy, This is an extendedradical mastoidectomy with exenteration of the complete petrous air-cell system. The middle and posterior fossa duraare skeletonised, alongwiththelateral venous sinus. Bone is removed extensively from the latter and from the posteriorfossa dura in the retrosigmoid region. The mastoid tipand bony EAC are then removed, along with the drum and ossicular chain lateral to the stapes. The facial nerve is skeletonised from the geniculate ganglion to the stylomastoid foramen. Anterior transposition of the facial nerve. A groove is cut in theanteriorattic region andthe facial nerve transposed into the parotid and secured with a sling of fascia lata (see Fig. 20.1 1). Ligation of thesigmoid sinus, Theposterior fossa dura is incised and blunt-tipped a aneurysm needle passed throughthedural incision alongthe posterior wall of the sigmoid sinus. A second dural incision is made over thetip of the needle when it becomes visible through the dura medial to the sinus. In this way a 2/0 silk tie is passed around the sinus. The process is repeated and the sinus can be divided between the ligatures. Duringthis process, there is a CSF leak; hence theimportance of thesubtotal petrosectomy and obliteration of the middle ear cleft to avoid CSF leak. In view of this, a lumbar drain is placed in an attempt toreduce the risk of a persistent leak.

Fig. 20.9 Incision for infratemporal fossa approach for glomus jugulare.

Exposureof ICA distal to tumour. Theintrapetrous ICA can be exposed using the medial wall of the Eustachian tube as a guide. This is necessary not only forexposure of thetumourbut also forcontrol of thedistal ICA (see Fig. 20.12). If exposure is

Fig. 20.10 Blind-sac closure of the external auditory canal.

the parotid mustbe separated from the tympanic bone). If using this retractor, great care must be taken to protect thetransposed facial nerve-it is all too easy to damage the nerve one has worked so hard to preserve when pushing the parotid anteriorly! Obliteration of Eustachian tube. The lumen may be packed with bone wax, muscle, fat or bone pate in an attempt to obliterate it. Ligation of the IJV. The IJV is ligated, transfixed and divided in the neck and the tumour mobilised from the neck and opened jugular foramen. Tumour dissection and excision. Isolation of the intrapetrous ICA distal to the superior tumour margin allows forcontrol of this vessel andtumourcan be dissected from it. Once free from the ICA, tumour removal proceeds as described above. Fig. 20.11 Anterior transposition of facial nerve.

inadequate,themandibular condyle can be displaced anteriorly and inferiorly. Thisexposure is difficult to maintain and the most efficient device isthe Fisch infratemporal-fossa retractor (prior toinserting the retractor,

Closure. Fascia latacan be used to repairanydural defect and fat is used to obliterate the temporal-bone defect. An excess of fat is used to provide a tight closure of the cavity. A temporalis-muscle flap can be rotated to cover the cavity. The skin is closed in two layers with 310 catgut and 4 0 prolene. A pressure dressing is applied and left in

Surgery of Glomus Tumours of the Temporal Bone '*.I ' 1

~

~.

I 53

*

Fig. 20.12 Exposure of internal carotid artery distal to tumour.

place for 3-4 days. A compression dressing is also applied to the leg.

Postoperative Management There is usually a period of facial weakness (when there has been transposition of the nerve) requiring possible measures for eye care. Themajor problems relate to palsies of the nerves of the jugular foramen and the subsequent dysphagia andaspiration. Initial feeding with a nasogastric tube may be required but with the help of the speech therapist the majority of young patients will return to an oralintake over the period of 34 weeks. If a lumbar drain has been used, then this is left in place for 5 days.

Infection and necrosis of fat grafts or muscle flaps is possible. CSF leak can occur whenthesubarachnoid space has been opened. Cranial nerve palsies are managed as above.

Fisch U & Mattox D (1988) Infratemporal fossa approach type A. In: Microsurgery of the Skull Base. Stuttgart, Thieme, pp. 136-80. Jackson CG, Johnson GD & Poe DS (1990) Lateral transtemporal approaches to the skull base. In: Surgery of Skull Base Tumours. New York, Churchill Livingstone, pp. 141-96.

sectomy T R I S T R A M H.J. LESSER

Petrosectomy is used in the treatment of malignant tumours of the external ear canal and middle ear cleft. Ideally the tumour should notinvolve any of the following: a dominant internal carotid artery (ICA); the temporal lobe; the cerebellum; thepars nervosa of the jugular fossa; or thepetrousapex; and it should be without distant metastases. The patient must be fit for an extensive surgical procedure and willing to risk the complications that may occur. There is no unequivocal evidence in the nearly 100 papers published that radical surgery improves the cure rate, except in T1 tumours of the ear canal. This is mainly because the tumours are rare and no controlled trial has been done. The patients are often in pain when they arrive so some treatment is required and, if the tumour is confined to the temporal bone, total and,if possible, en bloc resection followed by radicalradiotherapyshould be offered. If the dura, internal carotid, pars nervosa of the jugular bulb or petrous apex is definitively and extensively involved, palliative surgery and radiotherapy should be given.

Clinical examination will give some clues to the lateral and anterior extent of the tumour, particular attention being paid to the parotid region and the neck glands. Histological examination of the tumour will define the type of tumour, and biopsy is best done through the ear canal. Radiological assessment requires botha highresolution CT scan andan MRI,with andwithout contrast.Theformer will demonstratetheextent of bony destruction and the latter will give an indication of

dural and brain involvement. The MRI may not differentiate between retraction of the middle fossa and invasion. Angiographic studies are required if the carotid artery is at risk. If it is to be sacrificed, a temporary balloon occlusion is performed preoperatively with the patientawake. If no neurological deficits occur, the balloon is detached from the catheterand left in situ just proximal to the ophthalmic artery. If the jugular system is to be removed, adequate cross-flow needs to be demonstrated on the venous phase. As withanymalignant disease, metastaticspread should be excluded by careful history, blood tests, chest radiography, bone scans and liver ultrasound if indicated. Consideration must be given to the possibility of the temporal-bone lesion being a secondary itself. Theradiotherapistshouldplanthetreatment preoperatively, as early postoperativetreatment is often crucial. It is also important to introduce the patient to the rehabilitation team preoperatively: the physiotherapist, who will be doingthe vestibular training and facialnerve exercises; the speech therapist, who may be helping rehabilitate swallowing; and the nursing staff on the ward.

Relevant anatomy Temporal-bone anatomy is complex and involves many vital structures. Most cancers arise in ears that have had many years of chronic otitis externa or media and the anatomy may have been altered by previous surgery. The most relevant anatomy is the areas into which the disease spreads once it has occurred. The external ear canal has two parts, bony and cartilaginous. Tumours arising in the cartilaginous part have little resistance to

Petrosectom y spread. They spread anteriorly into the parotid gland, posteriorly to thepostauricular sulcus and laterally into the pinna. The bony part of the ear canal resists tumour spread for longer and it spreads medially into the middle ear. In the middle ear the tumours spread either anteriorlyastubotympanic or posteriorly as petromastoid tumours. Both types may spread upwards through the thinbone of the tegmen tympani and spread medially to involve the facial nerve through or around the otic capsule into the petrous apex.If the patient has alreadyhad mastoid surgery, thereareothernonanatomical routes opened up as well, and the jugular bulb may be invaded withoutobvious direct disease extension. Other important routes are the facial canal, the Eustachian tube and thereby into the ICA canal, and via themastoidair cells intotheinternalauditory meatus (IAM) and thus into thecranial cavity. Some anterior tumours spread along the Eustachian tube or its surrounding fascial spaces and involve the trigeminal nerve and cavernous sinus nerves. Lymphatic drainage may go to the parotid, deep cervical or mastoid nodes fromtheearcanal.Distant spread is unusual.

Operative technique Preparation

The patient is placed supine under a general anaesthetic (GA) onthe operating table, thehead turned so that the diseased ear is facing up and sandbag placed under the shoulders. Facial-nerve monitoring is attached and sterile draping applied. Incision

A preauricular incision similar to a large parotid incision is preferred (Fig. 21 .l).This heals quickly and avoids delay in startingradiotherapy. If thetumour invades posteriorly or if there has been previous violation of thepostauricular skin, e.g. mastoidectomy, a postauricular incision is used. A second incision cutting aroundtheearcanaloracrossthepinna is made, the position depending on the lateral extent of tumour. Procedure in stages

1 Flaps are elevated to expose the whole of the parotid anteriorly,theretromastoidarea posteriorly andthe upper neck inferiorly. The ear canalis sutured closed in order to avoid tumour spillage. The zygoma is followed

I 55

Fig. 21.1 Preferred incision.

as far as the lateral orbital margin and the temporalis muscle exposed superiorly. 2 The facial nerve is divided. If the parotid is involved, this is done peripherally; if not, it is found in the usual way in thetemporomastoidsuture and divided. The parotid is reflected either posteriorly or anteriorly from the masseter (Fig. 21 2). 3 The upper neck is explored and the greater auricular nerve is dissected out andmarked for lateruse as acable graft. Any lymph nodes are sent off for frozen section and, if involved, a radical neck dissection is done. Otherwise thecarotid vessels and the jugular nerves and vein are identified and controlled.Thesternomastoid muscle and digastric muscle are divided from the mastoid bone. 4 The masseter is reflected from the zygoma and mandible andan osteotomymade at each end of the zygomatic archand acrosstheposterior part of the mandible. This part of the mandible is removed, including the condyle, after cutting the ligaments on the medial surface with Mayo scissors (Fig. 21.3). 5 Thetemporalis muscle is reflected downwardsto expose the infratemporal fossa, care being taken to preserve the deep temporal vessels on its deep surface (Fig. 21.4). If the resection is to include the infratemporal fossa, the pterygoid muscles can be removed from their plates and the drill used to remove the bone of the floor

Fig. 21.2 Facial-nerve cut.

Fig. 21.4 Temporalis reflected, exposing infratemporal fossa.

of the anterior part of the middle fossa. The middle meningeal artery and then the mandibular branchof the trigeminal nerve are diathermied and cut as this is done. 6 The muscles attaching to the styloid process are cut. The external carotid artery (ECA) is followed distally and branches divided, except those deep temporal ones supplying the temporalis muscle if this is needed in the reconstruction. 7 The Eustachiantube is cutand sutured at its cartilaginous part.

8 The ICA is exposed on the medial wall of the Eustachian tube and any further bone lateral and anterior to it removed. This completes the anterior dissection. 9 The middle fossa is then explored. Thebone over the temporal lobe is removed and the duralifted off the floor of the middle fossa. If the dura is involved, this is kept attached to the bone and the elevation done intradurally as far medially as the superior petrosalsinus. 10 Posteriorly the transverse and sigmoid sinuses are exposed, using the drill, and followed inferiorly towards the jugular bulb. If themastoid is free of tumour, a translabyrinthineapproach to the IAM is done (Fig. 21.5); if not, a presigmoid dural incision with retraction of the sigmoid allows exposure and division of the VIIIth and VIIth nerves. The VIIth nerve is marked for later grafting. 11 At this point, the temporal bone, hopefully containing the tumour, can be removed from its deep attachments (Fig. 21.6). This is traditionallydonewitha curved osteotome, making two cuts: the first from superiorly down from the IAM and another from the internal carotid back towards the first. This causes profuse bleeding and damages the jugular bulb and sometimes the jugular nerves. An alternative is to free almost all the bone deeply, under controlled drilling, with a final cut

Petrosectomy

I: 57

wards. If these two vessels have been controlled, an even more medial bony block can be removed. 13 Following haemostasis, a careful search is made for residual tumour, any dura or further bone removed and, as far as possible, margins sent for frozen section. 14 The greater auricularnerve is used as a cable graft to repairthe facial nerve, and alateraltarsorrhaphy is done. 15 The cavity isfilled witha free vascularised graft, usually rectus abdominis with or without a skin paddle, or occasionally latissimus dorsi. 16 If the jugular nerves have been interfered with, tracheostomy and percutaneous endoscopic gastrostomy (PEG) tubes are inserted. Aspinaldrain is not routinely used.

Fig. 21.5 Translabyrinthine posterior dissection.

Every attempt is made to close the dura. Thefree flap is sutured deeply and to the subcutaneous tissue. The skin is closed tightly over this. Two drains are used, one to the neck and one subcutaneously.

The patient is carefully monitored on the ward for48 h. Antibiotics are continued for 5 days.

Fig. 21.6 Final mobilisation of temporal bone.

using a guided Gigli saw ora small amount of chiselling. This causes much less bleeding from thejugular vein and tributaries. 12 If the jugular system is to be sacrificed, it is fully exposed posteriorly, opened, packed with muscle and sutured over (avoiding Labbi’s vein). Thevein is tied in the neck. The bulb is fully exposed and the inferior petrosal veins are packed lightly with oxidised cellulose. The ICA can be resected if it has been occluded preoperatively with a balloon or can be mobilised for-

These are the same as with any lateral skull-base surgery. These are vascular, including stroke, swallowing and aspiration problems due to jugular-nerve damage, CSF leaks and meningitis, as well as the general complications of:surgery. CSF leaks are the bane of skull-base surgery when the dura is breached. If they occur, there will often need to be further procedures, with repeat lumbar drainageand occasionally even shunting to avoid the risks of meningitis. This should be done early rather than late, in order to avoid delays in starting postoperative radiotherapy.

lternat~weprocedu Less radical procedures are commonly done and there is a school of thought that says a lateral temporal-bone resection (basically a radical mastoidectomy, including removal of theanteriorcanal wall and most of the external canal skin), followed by radical radiotherapy, should be the treatment forall malignant tumours of the temporal bone. This is because radical surgery often fails to remove the tumour in one piece and seldom has

a truly oncological margin. Furthermore, complications are more drastic with more radical surgery.

Further reading Donald PJ (1992) Skull base surgery: combined results of treatment of malignant disease. In: Skull Base Surgery, Vol. 2, pp. 76-80.

Prasad S & Janecka IP (1994) Efficacy of surgical treatmentsfor squamouscarcinoma of thetemporal bone. Otolaryngol.Head Neck Surg. 110, 270-80.

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Nasal fractures constitute the most common form facial fracture.

of

Nasal septum

Anteriorrhinoscopy using aThudicum’s or Killian’s speculum will reveal swelling caused by septal a haematoma, the caudal dislocation of the quadrilateral cartilage off the maxillary groove orthe angulation of a septal fracture.

The most frequent indication for surgical intervention is to correct the cosmetic deformity of simple nasal bone displacement. A septalhaematomarequiresurgent drainage, but other simple injuries can be reviewed 710 days after the injury to allow local tissue oedema to settle. More severe force causes complex injury to surroundingstructures (Fig. 22.1).Management of these associated injuries usually involves team a approach of maxillofacial, neurosurgical and ophthalmology expertise.

Surrounding structures

Orbital movement, visual acuity and lachrymal-duct obstruction are assessed if indicated. A possible cerebrospinal fluid (CSF) leak should be confirmed by testing for glucose.

Standard lateral nasal X-rays play little part in the assessment and management of nasal fractures (De Lacey et al., 197’7).X-rays may reveal evidence of fractures of surrounding bones (orbitalblow-out,frontoethmoid and maxilla). Severe injuries should be assessed by CT scanning.

Forces areapplied in three different planes, and, depending on the extent of force, either nasal bone, nasal septum or surrounding injurywill occur. Some detail of previous injury, deformityor surgery may help in assessing the current injury.

(Fig. 22.1)

The nasal dorsum consists of two nasal bones, supported by thenasal process of thefrontalboneandthe frontal process of the maxilla. The nasal root consists of Nasal pyramid thick nasal bone which thins inferiorly to overlap the Lacerations, bruising, lateraldeviation or depression upper lateral cartilages. This thinned bone usually fracshould be noted. Tenderness and a step deformity may turesduringtrauma,oftenwithanassociatedseptal localise thefracture line. Cosmeticdeformity is best fracture occurring at the bony-cartilaginous junction. assessed by standing behind the seated patient and look- Nasal bones may fracture unilaterally, causing depression of onenasalbone, or bilaterally, causinglateral ing down the nasal contour. 161

Fig. 22.1 Nasal anatomy relevant to nasal fractures.

The blood supply to the nose is via branches of the internalcarotid(anterior and posteriorethmoidal arteries supplying the upper third of the lateral nasal wall andseptum)and externalcarojid(internal maxillary artery passing posterior to t h e maxillary sinus with branches to the lower two-thirds of the lateralnasal wall and septum). Local anaesthetic (LA)techniques can be used to correct simple nasal fractures (Fig. 22.2). The nasal mucosa can be anaesthetised with cocaine- or lignocaine-soaked pledgets placed superiorly to block the anterior ethmoid nerve and atthe posterior endof the middle turbinate to block the sphenopalatine ganglion. Lignocaine can be locally infiltrated to block cutaneous sensation supplied by theinfratrochlear,externalnasal and infraorbital nerves.

A-P, anterior-posterior; CSF, cerebrospinal fluid.

Operative technique Preparation

deviationandlorposteriorimpaction of thenasal pyramid. Minor forces to thecartilaginousseptumare absorbed without injury. More severe lateral or anteriorposterior (A-P) forces result in vertical, horizontal or mixed septal fractures.

General anaesthesia with intubation provides the safest method of controlling the airwayto allow manipulation of nasal bones, including possible septal correction. No antibiotic or steroid cover is required. Thepatient is positioned prone withslight head-up tilt. No skin preparation or drapes are required but, if septal surgery is

Surgical Correction of Nasal Fractures "

2

163

.

Fig. 22.2 Sensory nerves of the nose. (a) External. 1, Infratrochlear nerve; 2, supratrochlear nerve; 3, external nasal nerve. (b) Internal. 4, Sphenopalatine nerve; 5, anterior ethmoidal.

considered, formal surgical preparation should undertaken.

be

Procedure

Nasal bones

1 Clinical assessment by lookingdownthe nasal contour. 2 Walsham's forceps-small blade inserted under individual nasal bones androtated laterally to initially outfracture nasal bone. 3 Nasal bones are then infracturedby applying external thumb pressure to narrow and medialise the nasalbones. 4 Nasal bone elevation is supportedwithintranasal packing if the nasal bridge has collapsed (bismuth, iodoform and paraffin paste (BIPP) or antibiotic ointment-impregnated gauze). 5 Nasal tape is applied to the skin overlying the dorsum if the nasal fracture is stable. If thefracture isvery mobile, a small plaster-of-Paris or plastic external castis applied over the nasal bones to protect against further minor trauma. Nasal septum

l An attempt can be made to manipulate minor nasal septal deviations using Asch's forceps introduced on either side of the septum.

2 Septoplasty with resection of a small area of bone or cartilage at the fracture line may allow the nasal septum to return to a normal position. This should only be done to correct severe angulation (Murray et al., 1984; Murray, 19 89). 3 Septal haematomas should be drained by incising the mucoperichondrium anteriorly, introducing a sucker to evacuate thehaematoma.Quiltingsutures, using 4/0 catgut or 410 Vicryl, are used to close the space created by the haematoma. A small rubber-tubing drain can be inserted at the most dependent site of the incision and the nose packed bilaterally with BIPP or other dressings for 24h.

Most patients can be managed as day-case admissions. A11 patientswithseptalhaematomasshould be given broad-spectrum oral antibiotic cover for 5 days. Nasal packs should be removed 1-2 days postdrainage.

Haemorrhage often occurs after the use of Walsham's forceps, but can be controlled with simple nasal packing. Nasal packs, however, should be avoided if possible, as they may displace the corrected nasal bones or septal fractureline. They should alsobe avoided if a CSF leak is suspected.

164

Chapter 22

Failure to adequately correct the deformity mgy be due to: 1 previously healed nasal fracture and displacement; 2 difficulty correcting the septal deviation; 3 inadequate stabilisation of the fracture. Many of these cosmetic and functional airway problems can be dealt with electively by formal septorhinoplasty techniques.

Alternative procedures This chapter does not detail the surgical management of complex nasoethmoid fractures. These fractures require open surgical exposure via a bicoronal or local external nasal incision. Thefracturecanthen be reduced and

plated or wired to support (Bowerman et al., 1985).

the nasal pyramid

References Bowerman JE, Fordyce G & Levant B (1985) In: RoweNL & Williams JLI (eds) MaxillofacialInjuries. Edinburgh, Churchill Livingstone, pp. 376-400. De Lacey GJ,Wignall BK, Hussain S & Reidy JR (1977) The radiology of nasal injuries: problems of interpretation and clinical relevance. Br. J.Radiol. 50 (594), 412-14. MurrayJAM(1989) Management of septal deviation with nasal fractures. Facial Plast. Surg. G (2), 88-94. Murray JAM, Maran AGD, Mackenzie IJ & Raab G (1984) Openv. closed reduction of thefractured nose. Arch.Otolaryngol. 110 (Dec.), 797-802.

lary Sinus Lavage and ior Meatal Antrostomy J O H N M. HADLEY

~ndications The indications for maxillary sinus lavage and inferior meatal antrostomy can be considered as diagnostic and therapeutic. Diagnostic procedures include lavage to obtain specimens for microbiology and antrostomy to obtain specimens for histology. Therapeutic procedures include lavage to remove secretions in acute sinusitis and inferior meatal antrostomy to drain chronic sinusitis. Failure of acute sinusitis to resolve in spite of repeated lavage constitutes another indication for antrostomy. An inferior meatal antrostomy is also performed as an integral part of a Caldwell-Luc procedure to explore the maxillary antrum.

~ontraindications Children

Extra vigilance should be exercised in children because of the smaller dimensions of the antrum and the presence of the unerupted second dentition. Exacerbation of symptoms

Mucopurulent discharge may be made worse by cresting an inferior meatal antrostomy, which allows secretions todrain anteriorly and posteriorly, with exacerbation of postnasal drip.

Releuant anatomy (Figs 23.1 and 23.2) The antrum is enteredthroughthe bony wall of the inferior meatus, that is, inferior to the inferior turbinate. This structure forms part of the medial boundary of the

antrum and the lateral boundary of the nose. The wall is pierced at its thinnest point, a place approximately 1cm posterior to theanterior end of the inferior turbinate, which is marked by the apex of the inverted V-shaped attachment of the turbinate. Care should be exercised to avoid damage to thenasolacrimalduct opening anterosuperiorly, and posteriorly to the sphenopalatine vessels running vertically in the inferior meatus. The floor of the antrum descends in relation to the floor of the nose during facial growth, being at the same level at the age of 12 and lying inferiorly thereafter.Observations on the clearance of mucus from the antrum show that the antral cilia beat the mucus towardsthe middle meatus,the site of thenatural ostium of the antrum. The mucus stream may therefore bypass the inferior meatalantrostomy.Ventilation of the antrum, however, may be the more significant factor in reversing the hyperplastic mucosa of chronic sinusitis.

Technique Antral lavage may be performed under either local or general anaesthesia, and antrostomy is more commonly performed under general anaesthesia. Under local anaesthesia, the patient is seated, leaning slightly forward. The nose is anaesthetised using S% cocaine spray and then 0.5” m1 2.5% cocaine-paste-soaked cotton wool on Tumarkin wire carriers (Fig. 23.2). Under general anaesthesia, anoral endotrachealtube (ET) witha throat pack is employed and the nose is vasoconstricted with 5% cocaine solution. The patient is positioned in the reverse Trendelenburg (head-up) position. Visualisation of the interior of the nose requires the use of a speculum of the Thudicum’s or Killian’s type

Fig. 23.1 Anatomy.

Fig. 23.2 Nerve supply and local anaesthesia.

and head a light. The self-illuminating Killian’s speculum offers the convenience of inbuilt lighting.

slipped undertheinferiorturbinateunderdirect vision and will come to rest naturally at the apex of the attachment of theinferiorturbinate. Access to theinferior meatuscan be improved by infracturingtheinferior turbinate with a Hill’s elevator. 2 Perforation of the bony antral wall is completed with Antral lavage a gentle screwing action, while pushing the instrument 1 A Tilley-Lichwitz (Fig. 23.3) trocar and cannula are in the direction of the ipsilateral tragus. The index finger

~ a x i l l a Sinus ~ y Lavage

Fig. 23.3 Standard instruments for performing sinus lavage and inferior meatal antrostomy.

Hayek punch forceps

l

167

Ostrom‘s punch forceps

L

is placed along the shaft of the instrument to act as a safety stop (Fig. 23.4). The other hand may be used to steady the patient’s head. 3 After penetration of the bone, the trocar is withdrawn and the cannulais gently advanced to touch the opposite wall and then withdrawn about 1cm to sit within the antral cavity. Aspiration of fluid contents gives undiluted samples for microbiology. 4 Irrigation of the antrum with normal saline at 3’7°C is performedafteraspiration by connectinga 20ml syringe to the cannula. The syringe should be free of air to obviatethe risk of air embolism, and the use of excessive pressure on the syringe should be avoided. A second cannula can be inserted into the antrum if the natural ostium is blocked. The eyes should be observed for periorbital swelling during irrigation, which would indicate misplacement of the cannula. 5 Under local anaesthesia, the fluid is allowed to flow anteriorly out of the nose into a receiver, while, under general anaesthesia,the fluidis removed by suction, often under direct vision. Samples of the fluid may be sent for microbiology.

Inferior meatal antrostomy

1 Adequate exposure of the inferior meatus to permit access of surgical instruments requires infracture of the inferior turbinate using a Hill’s elevator. 2 The wall between the nasal cavity and the antrum is perforated with a Myles’ antronasal perforator where the bone is thinnest. 3 The antrostomy is enlarged under direct vision, posteriorly with Hajek punch forceps and anteriorly with Ostrom’s punch forceps. The size of the antrostomy is limited posteriorly by thesphenopalatine vessels and superiorly by the nasolacrimal duct (Fig. 23.1). Inferiorly, the antrostomy is lowered to the level of the floor of the nasal cavity to permit free drainage of the antral contents. 4 The turbinateis repositioned and the nasal cavity may be packed, if necessary, for 24 huntil bleeding has stopped.

168

Chapter 23 of the soft tissues of the cheek or theorbit occurs. Lavage should be stopped immediately, and suitable antibiotic treatment commenced. 4 Spread of infection to the maxillary bone is a rare late complication, and can be treated with antibiotics and debridement of the bone. 5 Some degree of circumferential stenosis of the antrostomy is inevitable, but complete closure is prevented by creatinga large antrostomy. An inferiorly based flap of the nasal mucosa can be preserved to line the floor of theantrostomyinorder to maintain patency. G Epiphora may occur, due to damage to the nasolacrimal duct, and is treated by dacrocystorhinostomy. 7 The anterior superioralveolar nerve may be damaged anteriorly.

Alternative procedures

Fig. 23.4 Perforation of bony antral wall with Tilley-Lichwitz trocar and cannula.

Complications 1 Under local anaesthesia, pallor, sweating and bradycardia with vasovagal collapse may occur; this is treated by the patient lying supine. 2 Bleeding can occur at the time of surgery but is rarely severe. Heavy bleeding may represent damage to the sphenopalatine vessels. It is managed by nasal packing for 24 h; if uncontrollable, it may necessitate the ligation of the maxillary artery. 3 Penetration of soft structures with the trocar during antral lavage should be recognised early, when swelling

Repeated antral lavage can be performed by the insertion of indwelling polyethylene catheters through the cannula, which is withdrawn. Antroscopy, using Hopkins rod telescopes to allow direct visualisation of the contents of the antrum, is a modification of antral lavage. Inferior meatal antrostomy has largely been superseded by themore physiological middle meatal antrostomy, on the basis that this represents the natural anatomical site towards which the antral cilia beat mucus (see Chapter 27).

Further reading Lund VJ (1987) Surgical management of sinusitis. In: Mackay IS & Bull TR (eds) Scott-Brown’s Otolaryngology: Rhinology, 5th edn. London, Butterworths, Ch. 11. Lund VJ (1988) Inferior meatal antrostomy: fundamental considerations of design and function. J.LarylzgoE. Otol. 102 (Suppl. 15). Maran AGD & Lund VJ (1990) ClinicalRhinology. New York, Georg Thieme Verlag, pp. 63-9.

Surgical Reduction of the Inferior Turbinates PAUL O’FLYNN

lndications 1 Relief of nasal obstruction: this may be achieved by reduction of the bulk of theturbinateor by lateralisation of the turbinate. 2 Biopsy to confirm a diagnosis of a systemic disorder, e.g. sarcoidosis, ciliary dyskinesia or Wegener’s granulomatosis, or to determine the precise histological diagnosis of an intranasal lesion.

Contraindication Turbinate surgery is relatively contraindicated in patients with known bleeding disorders.

Preoperative management In assessing patients for turbinate surgery, one should eliminate and treat any underlying cause for increased bulk of the turbinate. Such causes include allergy and infection. Prior to recommending surgery, skin allergy testing is desirable so that appropriate advice may be given concerning allergen avoidance and medications. Chronic rhinosinusitis producing mucopurulent discharge intothe nasal cavity may promoteturbinate enlargement. Appropriate history-taking and investigations are required to eliminate this possibility.

Relevant anatomy The inferior turbinate consists of a bony skeleton covered by respiratory mucosa and an underlying vascular plexus. The turbinate bone is attached laterally to the wall of the nasal cavity. The lateral wall itself is bowed in shape, making the nasal cavity wider initially before

narrowing posteriorly. Below the inferior turbinate is the inferior meatus (i.e. the space between the inferior turbinate and the floor of the nasal cavity). Procedures which ‘lateralise’ the turbinate achieve an increase in the nasal-cavity volume by displacing it into this space. The anterior end of the turbinate is positioned in the region of the nasal valve. This is the narrowest part of the nasal cavity. If the turbinate obstructs this region, a considerable reduction in nasal air flow occurs. Reduction of obstruction in this region, leading to a widening of the nasal valve, is the theoretical basis for anterior reduction of the inferior turbinate.

Operative technique for trimming of the inferior turbinates Anaesthesia

Local anaesthetics may be suitable for minor procedures to the turbinates. Many patients prefer a full general anaesthetic. Theanaesthetistshould pay particularattention to protection of the airway from blood, using either an orotracheal tube withpharyngeal packing or a laryngeal mask. Supplementary preparation of the nasal mucosa to achieve good vasoconstriction greatly facilitates surgery to theturbinatesand may be achieved using Moffett’s solution, cocaine paste or topical adrenaline, Instruments

Intranasal surgery is greatly enhanced by good illumination. Nasal endoscopes are not generally required for surgery to the turbinates, and the author prefers to use a fibre-optically illuminated nasal speculum.

1.70 Chapter 24

The clip is then removed and turbinectomy scissors are used to cut along the line demarcated by the clip (Fig. 2 4 . 1 ~ ) . 5 The resected turbinate is then removed by grasping it with a pair of forceps (Fig. 24. Id).

With the exception of linear cautery nasal packing is generally advised. Theauthor prefersTelfa dressings placed for 1-2 hours after submucosal diathermy (SMD) and multiple out-fractures. Overnight packing after turbinectomy surgery is desirable to prevent bleed1ng.

1 Nasal turbinates may bleed profusely (intraoperatively, primary haemorrhage within 24 h or late/ secondary haemorrhage after5”-0 days). 2 Excessive removal of theturbinatemay lead to atrophicrhinitis,particularlyin the Middle East and tropics. In the UK one may see crusting and discharge from the nose for a prolonged period of time. 3 Occasionally, secondary infection and osteonecrosis may occur, with associated foul smell or extrusion of necrotic fragments of residual turbinate.

There are a number of variations on trimming of the turbinates (Fig. 24.2).

\

Crushed inferior turbinate resected with scissors

~

,.;.

adical turbinectomy 1)

Anterior t r i ~ ~ i n g Fig. 24.1 (a) Bulky turbinate obstructs airway. (b) Inferior turbinate infractured. (c) Turbinate outfractured. (d) Turbinate removed.

1 This procedure is indicated where largeor bulky inferior turbinates obstruct the nasal airway (Fig. 24.1a). This may occur bilaterally or unilaterally in association with a deviated nasal septum. 2 Under general anaesthetic(GA),the inferior turbinate is first infractured, using a Hill’s elevator. This allows easier access to the inferior meatus (Fig. 24.1 b). 3 A straight artery clip or similar instrument is placed alongthe length of theturbinateandthen closedin order to crush the hypertrophied and vascular mucosa.

Inthis

simple proceduretheanterior

part of the

Fig. 24.2 Variations on trimming of inferior turbinates. A-A, line o f incision for total or radical turbinectomy; B-B, line of incision for partial turbinectomy; shaded area, tissue excised in anterior turbinectomy.

Surgical Reduction of the Inferior Turbinates turbinate only is removed. This part of the turbinate lies close to, or actually in, the nasal-valve region and removing it gives an increase to the cross-sectional area in this region, thus improving nasal air flow. Partial trimming of the turbinate

In thisprocedureonlythe medial fleshy part of the turbinate is resected. This is often sufficient to achieve a good increase in nasal airway without risking atrophic rhinitis.

In this procedure the bulk of the inferior turbinate is lateralised into the space normally occupied by the inferior meatus (Brain, 1987). This is achieved by applying pressure to the medial side of the turbinate, using either a Tilley’s nasal speculum or a dissector, such as a Hill’s or Howarth’s (Fig. 24.3). The main problem with this procedure is that the amount of lateral movement of the turbinate is fairly limited if this is attempted in one piece. The main advantage is that outfracturing is quickand simple and does not breach the mucosa. Outfracturing can readily be combined with other procedures on the nasal septum with little risk of adhesions.

171

In this procedure the turbinateis lateralised fully and the submucosal plexus of vessels is interrupted (O’Flynn et al., 1990). Theprocedure involves making a small incision on theanterior end of the inferior turbinate. A Hill’s elevator is then used to dissect the mucosa from the medial surface of the underlying inferior turbinate bone along its full length. A Howarth’s dissector is then introduced, and the angled end is applied to segments of the inferior turbinate, working from posterior to anterior,thus lateralising it and fragmenting it intoa number of pieces (Fig. 24.4). Good lateralisation is generally achieved, with little bleeding.

Fig. 24.4 Diagrammatic representation of multiple, submucosal outfractures of the inferior turbinate (from O’Flynn et al., 1990).

Fig. 24.3 Inferior turbinate outfractured laterally into inferior meatus.

Fig. 24.5 Diathermy-insertion. An insulated nasal speculum is not necessary because the anterior end of the swollen inferior turbinate is well clear of the blade-tip of a standard Thudicurn’s speculum. The electrode point is pressed against the intended point o f entry and activated to produce blanching of the mucosa.

Fig. 24.6 Diathermy (continued).The electrode is then advanced through this ‘devascularised’ spot, parallel to the floor of the nose and hugging the medial surface of the turbinate bone until, at between 5 and 7cm depth, the posterior end of the turbinate is reached. Art and judgement are required to follow the bone closely in its irregularities and to avoid ‘buttonholing’ the mucosa inadvertently.

ally a diathermy needle is passed three or four times, taking care touse electrically insulated instruments and being aware that the turbinate may bleed substantially. The effect of this procedure is to shrink the subrnucosal tissue of the turbinate and to increase the nasal airway (Figs 24.5-24.7). Linear cautery

In linear cautery, burns are madein the surface rnucosa, either electrically or using chemical cautery alcm g the medial surface of the turbinate. This is a quick simple procedure, which is generally bloodless. It can satisfactorily be performedunder local anaesthetic (LA)in adults. The procedure may act by producing scarring of the turbinate, thus causing it to shrink, or may reduce the secretory-cell population of the mucosa.

References Fig. 24.7 Diathermy-coagulation. The diathermy circuit is closed while the electrode is gradually withdrawn so that a submucosal linear burn results, with minimal injury to the mucosal surface. In more severe cases a second or even third ‘run’ may be made, parallel to the first, if a greater degree of shrinkage is required.

Submucosal diathermy to the inferior turbinate

In this procedure the diathermy is passed submucosally along the length of the turbinate (Groves, 1986). Usu-

Brain D (1987) In: Kerr AG (ed.) Scott Brown’s Otolaryngology,Vol. 4, 5th edn. London, Butterworths, pp. 174-8. Groves J (1986) Coagulationdiathermy in thetreatment of nasal obstruction. In: Ballantyne & Harrison (eds) Rob alzd Smith’s Operative Surgery, 4th edn. London, Butterworths, pp. 83-5. O’FFlynn l? et al. (1990) Multiplesubmucosalout-fractures of the inferior turbinates. J.Laryngol. Otol. 104, 239-40.

Septoplasty and Repair of Septal Perforation CHARLES A. EAST

Septoplasty

Careful analysis of the deformity must be performed by complete external and intranasal examination (if necessary by nasal endoscopy, particularly for the valve region). Itis always helpful to decongest the nasal mucosa to allow thorough examination of thewholeseptum back to the choana. It is also informative to palpate the nasal septum, particularly if the patient has undergone previous nasal surgery. A floppy septum requires care in dissection to prevent a perforation, and the absence of cartilage means an alternative sourceis required for graft harvesting. The evaluation should define whether there is a leading-edge deformity, a central septaldeformity or acombination of both. This dictates the surgical approach required to correct the nasal abnormality.

combined withtopicaladrenaline. Application isvia ribbon-gauze strips or cotton pledgets. Moffett’s solution, a particularly effective method of preparing the mucosa, is prepared by acombination of 2 m1 10% cocaine solution, 2 m1 of 1:1000 adrenaline and 5 m1 of 0.9% bicarbonate. Monitoring of the pulse, blood-pressure and oxygen saturation should be used, especially if concomitant sedatives are administered. Caudal septal deformities can often be corrected under local topical anaesthetic supplemented by infiltration of 2% lignocaine and 1:80 000 adrenaline. General anaesthetic (GA), preferably administered by a laryngeal mask, is the usual preferred option in the IJK for more extensive procedures. The head of the table should be raised and the patient’s head turned to the side of the surgeon. Hypotension is not usually needed but a controlled blood-pressure and pulse are important. Hydrodissection of the submucosal plane with 0.5% lignocaine and 1:200 000 adrenaline facilitates raising of the septal flaps; 1-2ml may be infiltrated. Prophylactic antibiotics, e.g. Augmentin, are mandatory for all procedures involving grafting or implants. Porous implants, e.g. Goretex, should be impregnated with antibiotics by creating a vacuum in a syringe containing the implant and solution.This is done by occluding the syringe end while pulling back the plunger. In patients who have severe rhinitis, perioperative dexamethasone, 4-8mg, has a significant effect in minimising the reactive oedema in the postoperative period.

Preparation

Approaches (Fig. 25.1)

Adequate preparation of the mucosa is essential for any septal procedure: mucosal anaesthesia and vasoconstriction is achieved with a 5-10% cocaine solution

Killian (mucosal) incision

Indications

Septal deviations producing nasal obstruction. Correction of external deviation (acute or chronic). Donor site for cartilage grafting. Augmentation of saddle. Alteration of nasolabial angle. Repair of septal perforation. Insertion of dorsal spreader grafts for valve insufficiency. Preoperative management

This is a vertical incision approximately 1.5cm behind

Fig. 25.1 Incisions for approaches to the septum.

thecaudalseptalborderthroughtheperichondrium down to cartilage. It is relatively easy to get into the subperichondrial plane through this approach, identifying the characteristic blue and slightly shiny appearance of the cartilage, especially after hydrodissection. The perichondrial flap is usually raised on the easier side first (usuallythe concave side), without producing a tear. Sharp dissection may be required over the site of a previous fracture. The mucosa over a spur orangulation is often atrophic and easily torn, so contralateral safe flap elevation is recommended before tackling the spur. The lower part of this flap has a tendency to tear along the vomerine junction unless narrowbladed retractors, e.g. Cottle, are used. This approach is ideal for harvesting cartilage, correcting deformities of the perpendicular plate of the ethmoid and excising vomerine spurs. It is not possible to address problems of the anterior septal angle, caudal septum, columella or nasal spine regions. Hemitransfixion

This is a vertical incision in the vestibular skin of one side of thecaudalborder of theseptum.It is best donewiththe skin retracted using a short thinbladed self-retaining speculum, e.g. Cottle. The incision extends from the anterior septal angle right down to the nasal spine. Elevating this flap is more difficult, asthe fibres of theperichondriumare tightly bound down. Toothed Adson forceps, a sharp dissector, e.g.

Mitchell trimmer or Freer elevator, and some patience are importantto ensure that elevation of the flaps occurs inthecorrectsubperichondrial plane. Thisapproach allows access to the premaxillary area and the whole septum, if necessary using bilateral mucoperichondrial flaps. This incision must always be repaired,asit is made via skin. Transfixion

This is a vertical incision through the entire membranous septum at the caudal end of the quadrilateral cartilage. An assistant stabilises the medial crura with a pair of non-toothed columella forceps. The full incision separates the medial crural attachments to the septum and therefore there is a tendency to reduce tip projection.A‘short’transfixion incision halfway down the caudal border of the septum avoids this potential problem, while still allowing access to the dorsal septumand valve regions. Shortening of the nose is usually performed via a transfixion incision removing both cartilage and skin. Excess skin in this area does not take up following surgery, as it does over the nasal dorsum. Suture repair of this incision is mandatory to avoid the complication of a perforation. External incision

This approach provides unparalleled exposure of the

Septoplasty and Repair o f Septal Perforation

I 7s

planes requires sharp dissection. The creation of inferior tunnels is relatively traumaticand only necessary if there is a large low spur blocking theairway or for thecreation of transposition flaps to close a septal perforation. Access to the floor of the nose can usually be achieved after elevation of an anteriodsuperior tunnel past the osseocartilaginous junction. Dissection inferiorly over the bony perpendicular plate will gain access to the nasal floor posteriorly. Using a sharp curved Freer dissector, the decussating fibres can be dissected retrogradely from posterior to anterior. Basic technique Fig. 25.2 The external approach.

dorsalseptal region and permits themostcontrolled elevation of septal flaps in high septal deviation, in revision surgery and in the closure of septal perforations. Considerable care is required with the columellar flap. The incision combines a marginal incision caudal to the lower lateral cartilage with a horizontal broken midcolumella incision (Fig. 25.2). The totallength of the incision is approximately 5cm. Elevation of the skin over the lower lateral cartilage from lateral to medial and then caudal to the medial crura should precede the transcolumella incision. In this way the flap is then just lifted off the nose and not dissected up from inferiorly with potential damage to the flap tip. Meticulous and accurate closure, usually with five 6/0 nylon sutures, is important to avoid unsightly scarring and notching in the midcolumella. Flap elevation

The principal goal is to achieve adequate exposure of the skeletal framework to allow correct mobilisation, excision and repositioning of theabnormal elements in order to achieve a straight septum without compromising structural support or creating further deformities. This may involve unilateral or bilateral elevation, depending on the position and extent of the deformity. Flap elevation can be performed with aFreer's or Cottle elevator to theperpendicularplate posteriorly and thendowntothe decussating fibres inferiorly. The anatomy of the septum and decussating fibres dictates varioustunnels:superiordown to the septovomerine junction and inferior tunnels over the vomer and, if necessary, onto the nasal floor. Joining these tunnels between the subperichondrial and subperiosteal

Elevation of mucosa should proceed posteriorly to include the perpendicular plate of the ethmoid either unilaterally or bilaterally. The osseocartilaginous junction should be dislocated, usually by a Freer dissector from the vomer superiorly, but leaving the attachmentunderthe nasal bones (keystone area). If the osseocartilaginous junction is not clear, aposterior chondrotomy is performed behind an imaginary line fromthetip of the nasal bones to the nasal spine. The contralateral mucoperiosteal elevation is then performed (Fig. 25.3). Following this, a strip of cartilage is excised from the inferior septal border adjacent to the vomer. This allows displacement of the quadrilateral cartilage with the self-retaining retractor andallows correction of posterior bony deviations, usually by excision with punching forceps, e.g. Jansen-Middleton (Fig. 25.4). Removal of bone in this area does not compromise nasal support, but care must be taken not to tear or twist the bone, as there is a small risk of damage to the cribriform plate withexcessive manipulation of the perpendicular plate. If the posterior septal angle is displaced fromthe nasal spine, it is usually necessary to remove a piece of cartilage from theinferior margin to allow central positioning. The new posterior angle must be sutured to the periosteum with a figureof-eight stitch, using an absorbable suture, e.g. Vicryl. Vomerine spurs are removed with an osteotome or gouge if they are large. Occasionally they can be fractured back to the midline if small. Near-total mobilisation of the septum involves separation of the dorsalattachments to theupperlateral cartilages, a manoeuvre that is usually required in the scoliotic nose. This should be performed extramucosally, as close as possible to the septum. In this case, it is important to leave an area of perichondrium attached to the middle part of one side of the cartilage by creating a high septal tunnel.

Fig. 25.3 Bilateral flap elevation over the perpendicular plate and vomer after separation of the quadrilateral cartilage.

Fig. 25.4 Area of resection in septoplasty where the quadrilateral cartilage is straight.

Specific problems

Displaced caudal margin

This may be dueto a vertical fracture and is often associated with a contralateral midcavity deviation and

external deviation of thenasal tip. Minorcaudal displacements only, with no columellar retraction, can be excised but keeping the new leading edge in the normal line with the superior andinferior angle. If there is an acuteangulation,a vertical-strip excision of the fracture line from the convex side is performed and the

S e p t o p ~ ~ $ t ~ Repair ~ a n d of SeptalPerforation mobilised cartilaginousseptum repositioned intothe columella by retrogradely dissecting a pocket. The two fragments should be stabilised by a Wright suture (Figs 25.5-25.8). ‘Bent’ cartilage

Vertical bending requires full-thickness vertical scoring on the concave side with the contralateral perichondriumattached to cartilage to produce floating strips. Horizontal bending is treated similarly and, in combined deviations, a chequer-board effect is created with islands of cartilage still attached to contralateral

177

perichondrium.The cartilage and perichondriumare then coapted with interrupted plain catgut sutures and the septum supported with a light intranasal dressing. Wide septum

The cartilage may be abnormally thick or there may be subperichondrial fibrosis from previous trauma. Thickening in the area of the septal tuberculum can limit the airway, producing a ‘pinched nose’ feeling. Excision of this cartilage, as in a classic submucous resection (SMR),is advisable, but always leaving adequate dorsal and caudal support.Coapting sutures should be used to close the interperichondrial space. Sagging dorsum- saddle/high dorsal irregularities Loss of support in the cartilaginous dorsum may pro-

Fig. 25.5 Correction of a vertical fracture to replace caudal displacement of the septum.

Fig. 25.6 Strip excision of vertical fracture lines.

duce a saddle deformity. The bony cartilaginous dorsal junction (keystone area) should always be respected during surgery, but, if mobilisation does occur peroperatively, particularly where all the septal margins have been mobilised, then through-and-through a percutaneous suture tied over Silastic may be necessary to maintain the dorsal profile. Saddles can be repaired by advancement of the remaining perpendicular plate of theethmoidafter bilateral mucoperichondrial-flap elevation, with suturing of the new septal angle to the nasal spine. A twisted or fractureddorsal edge will

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Chapter 25

Fig. 25.7 Strip excision of horizontal fracture lines.

Fig. 25.8 Septal fixation sutures (Wright and ‘figure-of-eight’).

require reshaping, and both these manoeuvres can be very satisfactorily dealt with via the external approach, which gives unparalleled access to thisarea.Further augmentation of saddles is possible using auricular cartilage, which can be directly sutured or glued in place

and fixed to the overlying skin,withthesupporting suture taped over the dorsum. This stitchis then cut off flush with the skin after1 week. It is not unusual for the nasal tip to need some form of augmentation (interdomal suture, strut graft) and again this can be

SeptQplas~y and Repair o f Septal Perforation

179

Fig. 25.10 Quilting sutures.

Fig. 25.9 Lateral augmentation of dorsum and valve region by spreader grafts.

easily achieved via the external approach. To guarantee firm support, the upper laterals can be sutured directly to the septum. Finally, the dorsolateral septal cartilage can be augmented, using a spreader graft to restore the relations of the nasal valve (Fig. 25.9).

sponge, is ideal. Splinting should be unnecessary except where there hasbeen extensive mucosal damage. Splints areuncomfortable andareassociatedwitha higher incidence of septal perforations. If they are used, e.g. after division of septaladhesions,theyshould be removed at 7-10 days. External nasal taping is not routinely required if the dorsal skin has not been elevated from the septum or upper lateral cartilage complex.

Closure and dressings

Packing is the least popular part of nasal surgery forthe patient, and can be avoided in many cases by use of a coapting or quilting sutureto the septum. Plain gut, not along-actingsuture, is preferred,as support is only required for a few days. Ordinary Vicryl or PDS can produce crusting for several weeks until the suture dissolves. Fast-dissolving Vicryl is likely to replace catgut in the future. Stitching virtually eliminates the possibility of a septal haematoma.Any mucosal tears caneasily be repaired, using a thin cartilage plate as support in between the tornleaves. A 16mm needle with 410 suture is ideal for this (Fig. 25.10). Knots are tied at the nostril and run down inside the nose by pushing the distal end of the suture towards the nasopharynx. Any skin incisions, e.g. hernitransfixion1transfixion or external, must be repaired. Inside the nasal vestibule, a 410 stitch is sufficient. For the external incision, five610 nylon sutures with accurate skin apposition, particularly at the nostril rim, are needed. The suture line should be covered with chloramphenicol ointment to prevent crusting, and the stitches removed at 5 days. If packsare used, anon-adherent dressing, e.g.Telfa or Merocel

Haemorrhage

The sphenopalatine artery is the usual cause of a reactionary or secondaryhaemorrhage.Occasionallythe septal incision may bleed. Any oozing can be minimised by nursing the patient at 45" as soon as helshe is conscious and forat least 12h. Reactionary haemorrhage of more than a slight ooze usually needs further action: analgesia and sedation if the blood-pressure is high or insertion of a nasal packif brisk bleeding occurs and the site cannot easily be identified. Merocel nasal sponges are an easy gentle dressing and can be slid straight into the nose and then hydrated with minimal damage or disturbance to themucosa.Ribbon gauze or balloon catheters will produce more mucosal damage with the possibility of adhesions or displacement of the septum, which may require revision surgery. In severe bleeding, return to theoperatingtheatreand-occasionallytransfusion maybe required,althoughthis is unusual if noconcomitantturbinatesurgeryhas been performed.

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Chapter 25

Septal haematoma Thisthreatensthe remaining septal cartilage with avascular necrosis and is complication a avoided by coaptingtheseptum. Sometimes it is difficult to differentiate between haematoma a and massive oedema, which occurs in severely rhinitic mucosa. Established haematomasshould be drainedassoonas possible if they block the airway, and the patient given antibiotic cover. Persistent deviation This is usually due to faulty technique but may occur after procedures, such as morselisation, which produce unpredictable scarring. A persistent high deviation will never let the septum hang straight like a curtain. Crusting This occurs because of mucosal loss and is usually temporaryuntilregeneration occurs. Physiological saline douches and barrier creams minimise theproblem. Occasionally the vestibule becomes colonised by staphylococci, necessitating an antibiotic ointment. Septal perforation Septal surgery is still the commonestcause of this mainly avoidable complication. Bilateral overlapping tears, excessive cartilage removal, septal splints and flap necrosis may predispose to a perforation. Generally, septal perforations where the anterior marginlies behind the level of the head of the inferior turbinate are asymptomatic. Anterior perforations are liable to produce crusting or bleeding and soreness. Manypatientscomplain of a blocked-nose feeling. Avoidance of perforations is extremely important, repairing tears accurately and supporting the mucosa with cartilage. Symptomatic perforations can be managed with barrier creams and nasal douches, obturated with aSilastic button or surgically closed. Surgical closure is the only definitive management and should be considered: (i) if the septum is not atrophic and can be split into two leaves; (ii) if the perforation is on average 2 cm or less; and (iii)if there is also a concomitant persistent septal deviation.

of practice is needed to be able to sew in the nose in a restricted area. The principle of perforation repair is to split the septum intotwo separate leaves, mobilising the nasal mucosa to create an inferior advancement flap from underneath the inferior turbinates and nasal floor and superior flaps from the roof of the nose, having separated the upper lateral cartilage from the septum. Intercartilaginous incisions, combinedwith bilateral staggered hemitransfixion incisions, which continue round the margin of the pyriform aperture up to the level of the inferior turbinate, are created. Superiorly, the upper lateral cartilage is separated from the nasal septum extramucosally (Fig. 25.11). It is important not to detach the upper lateral cartilage from the pyriform aperture, as this will lead to a cosmetic deformity and valvular problems. Inferiorly, a tunnel is created, ideally with a Cottle elevator, along the floor of the nose. It is better to start this dissection laterally rather than risk a tear at theseptovomerinejunction. A linear incision from the midpointof the inferior meatus is made to join the pyriform-apertureincision at the frontof the inferior turbinate. In completely mobilising the septal flap, it is better to try and dissect around the hole, using a curved Freer’s, before finally dividing the margins of the perforation. Thiswill minimise any risk of enlarging the hole. Having achieved complete mobilisation, the mucosa can then be delivered partly through the nose and held under tension by a temporary suture. This converts the round perforation into a slit, which can be closed with-

se Thiscan be done via an open or closed technique, depending on: (i) nostril size; (ii) size of the perforation; and (iii)need for nasal augmentation. A certain amount

Fig. 25.11 Sleeve dissection of nasal mucosa.

Septoplasty and Repair of Septal Perforation

7:

87:

Fig. 25.13 Composite closure of septal perforation.

Fig. 25.12 Closure of the hole as a straight line without tension.

out tension by interrupted catgut sutures (Fig. 25.12). This procedure is completed on both sides. Release of the stay suture allows thelining to retract, usually leaving a bare area laterally on the nasal floor. Finally, an interpositiongraft,either of periosteum,acomposite tragal/perichondrial or conchal cartilage and perichondrium, is placed between the septal leaves and secured by through-and-through transfixion sutures (Fig. 25.13). The pyriform aperture and hemitransfixion and intercartilaginous incisions arerepaired. The septal mucosashouldthen be protectedwiththincustomtrimmed Silastic sheets. Packing is not used and any ooze is collected with a nasal bolster.The Silastic sheets are left in place for 2 weeks. It is not always possible to close both septal flap perforations completely, and occasionally there is some marginal loss of the mucosa. In this case, an area of granulation appears on the septum and, when the Silastic sheets are removed, this must be protected with antibiotic ointment and barrier creams. Usually the patient has to be reviewed every 10 days or so for the first month.

The child’s septum Nasal injury is common in childhood and, following a septalfracture,deviationsare likely to increase with

further growth, particularlyif the injury occurredbefore the pubertal growth spurt. The growth centres in the nasal septum change with age, and therefore it is most unwise to undertake any septal correction until at least afterpuberty.Grosssaddling,however,mayrequire dorsal implantsto allow the nose to establish its normal length before definitive reconstruction. Failure to lengthenthe nose results in an infantileappearance, which is difficult to reconstructafterthe nose has stopped growing. In any event, the upper lateral cartilages should never be separated from the septum of a child, as these two conjoined elements, which form a Tshaped structure,have an importantrole in nasal dorsal development. If the airway needs improving, multiple outfracture of the inferiorturbinatesor laser crosshatching of the mucosa, together with control of any rhinitis, are useful holding measures.

References Cottle MH, Loing RM, Fischer GC & Gaynon IE (198.5)The maxillapremaxilla approachto extensive nasal septum surgery. Arch. Otolaryngol. 68, 303. Johnson CM 8c Toriumi DM (1990) Open StructureRhinoplasty. Philadelphia, W.B. Saunders. Kilian G (1905)The submucouswindow resection of the nasal septum. Ann. Otol. Rhinol. Laryngol. 14, 363. Mayer TG & Fleming RW (1988) Thenasal dorsum: open approach. Facial Plastic Surg. 5 , 143-59. Meyer R (1988) Secondary and functional rhinoplasty. In: Meyer R (ed.) The Difficult Nose. Grune & Stratton Inc, pp. 181-196.

Rhinoplasty Septorhinop NICK S. JONES

Rhinoplasty Rhinoplasty is not oneoperation. Each operation requires individual ‘tailoring’ to the needs and wishes of the patient and the form of the nose. The author has tried to produce a ‘pattern’ as abasis on which to work.

often less sympathy for people with minor developmentalabnormalities. In practice, what appears to beof overriding importance is the individual’s self-image. It is often the desire to appear ‘normal’ which is the reason for seeking surgery. Onlya few patientsare seeking ‘beauty’ for its own sake.

Indications

Reasons for seeking cosmetic surgery

Functional

1 Post-traumatic. 2 The individual’s perception of hislher nose as ‘abnor-

If the scaffolding of the nose is bent to one side, then a submucous resection or septoplasty will not completely correct blockage of the nasal airway. A better airway will result if the nasal bones, upper and lower lateral cartilages are repositioned in the midline. If aseptaldeviation is apparentexternally and is being corrected because of nasal obstruction,then it may be a good moment to consider correcting any cosmetic deformity. This is likelyto be the best opportunity to do so, asasecondary cosmetic procedure will be more difficult if the supporting septum has been partially resected or previously dissected.

mal’ and desire for ‘normality’. 3 Congenital abnormality. 4 Cultural differences. 5 Aesthetic demands. Contraindications

Unrealistic expectations

It is important to discuss patients’ expectations preoperatively, as these need to be matched with what can realistically be achieved. If they are unrealistic, then it is best not to proceed. One should be wary of people who cannot clearly define what they want to be done. It often indicates that what they are hoping for is some improvement in aspects of their life which cannot be achieved by surgery. Beware the person who brings a photograph or drawingof an idealised face and nose, as expectations are likely to be very high. Avoid surgery in patients who have had multiple previous operations, as their expectations are likely to be unattainable.

Cosmetic

People who have been injured often want their deformed nose returned to its original state and it is essential to discuss with them whatcan be achieved by surgery. People have different ideas about what makes an attractive or a cosmetically acceptable nose, and psychological factors play a major role in any surgery that alters facial appearance. While most people can empathise withsomeone whose nose is distorted by trauma or by a marked congenital abnormality, there is

182

Psychiatric illness

It is very unusual for patients requesting rhinoplastyto have a psychotic psychiatric illness, although this should of course be looked for. It is far more common to find that peopleseekinghelphave low self-esteem, minor anxiety neuroses or obsessive traits, which have in part becomefocused on their appearance. These problems should be considered and dealt with if rhinoplasty is contemplated,and the help of a clinical psychologist should be sought.

agreed upon them with the patient. See Table 26.1 for important points to notein the examination. Investigations

A flat middle third of the face or a receding chin are not absolute contraindications for rhinoplasty but if present they should be addressed surgically in order to achieve an optimal result.

Photography is essential for medicolegal reasons and it also helps in learninghowresultscan be improved. Standard facial, lateral and inferior views should be taken. Theangle of the head and the extent to which the frame is filled should be standardised so that the preand postoperative views can be compared. Symptoms that suggest chronic rhinosinusitiswarrant investigation, as it is unwise to do this type of surgery (especially if a graft is needed) when thereis concurrent infection. Other nasalpathologymayrequire specific tests, e.g. antinuclearcytoplasmicantibodytitres in Wegner’s granulomatosis or angiotensin-converting enzyme in sarcoidosis.

Preoperative management

Counselling

History

A clear and open discussion should take place about whatthepatientwantsandwhatthe surgeoncan achieve. Reference to preoperative photographs can be helpful, but constructing a computerised projected image as to whatis envisaged is usually counterproductive, as it may raise expectations and invites criticism if the nose is not identical with the image postoperatively. To temper patients’ expectations and for medicolegal reasons, it is essential to warn patients that a significant percentage of patients seek some finer ‘adjustment’ at a later date.

The influence of other cosmetic factors

It is important to enquire about previous trauma and surgery, in order to get some indication asto howmuch cartilage remains andhow much scar tissue, tethering of soft tissue and callus formation there will be. Patients who have had a previous submucous resection (SMR) are unlikely to have enough septal cartilageto allow any for grafting and need to be warned that cartilage may have to be harvested from the pinna. Revision rhinoplasty is more difficult as the anatomy is altered and planes are more difficult to define. You should ask about nasal symptoms: the patient may have coexisting pathology which shouldbe investigated and treated before embarking on rhinoplasty.Systemic disease which affects the noseis likely to be ‘stirred up’ locally by surgery, although some patients with quiescentWegner’s granulomatosis can undergo reconstruction. Ask the patient to define what they want done, and why. This is helpful in assessing their expectations and psychological state. Enquire about any other cosmetic surgery, as this will give an idea about their response to this type of surgery. Examination

It cannot be emphasised enough how important it is to define theabnormality.This is essential so thatthe correct surgical strategy canbe made. It is best to documentthe surgical aims clearly in thenotes,having

1 The superficial musculo-aponeurotic system (SMAS) of fat, muscle,nerves and vessels envelopsthenasal skeleton. The skin is thicker and more sebaceous near the tip but more adherent to the underlying cartilages. 2 Nasal bones often form the minor part of a hump. 3 The upper lateral cartilages are an integral part of the septum. 4 The nasomaxillarysuture line lies halfwayupthe lateral side of the nose. 5 The cribriform plate lies just above the intercanthal line. 6 The angular vein can often be seen anterior to the medial canthus 3-4mrn from the nasion. 7 The distal ends of the nasal bones make up part of the pyriform aperture. 8 The superior edge of the upper lateral cartilages is attached just under the inferior edge of the nasal bones.

184

Chapter 26

Table 26.1 Important points when examining the nose.

Rhinoplasty and Septo~binoplasty 9 The support of the septum is dependent on the following points: (a) the presence of an adequate amountof cartilage in continuity (24mm in the region of the columella and 28 mm along the dorsum); (b) support on at least two of the following structures: (i) the maxillary spine; (ii) the maxillary crest or vomer; (iii)the vertical plate of theethmoid (at least a 4 mm strut); (iv) continuity with the upper lateral cartilages; (v) a columellar pocket, with mattress sutures securing the anterior endof the septum within it,will offer partial support. 10 The medial crura are supported on the anterioredge of the septum. 11 The maxillary nasal spine is crucial as a foundation for the anterior strut of the septum and in maintaining tip projection. 12 The lateral crura of the lower lateral cartilages run far more ‘up and down’ (rather than‘side to side’) than most imagine. 13 The inferior marginof the lower lateral cartilage can be defined by palpating it with the blunt end of the scalpel handle. It starts where the vestibular hairs thin out. 14 The returning is the position wherethe upper lateral cartilages overlap with the lower lateral cartilages. 15 The nasal valve area is the area of maximum nasal resistance and is formed by the returning of the upper lateral cartilage, the inferior turbinate, the septum and the bony rim of the pyriform aperture, which can impinge on this area.

I8 5

Limited procedures can be done under local anaesthesia but most patients prefer general anaesthesia. Hypotensive anaesthesia helps the operative field, but a smooth ‘take-off, flight and landing’ in anaesthetic terms is also invaluable.

help prevent an exposure keratopathy. The head and neck are.extended, with one pillow placed well under theshoulders. Theauthor inserts 1Oml of Moffett’s solution (2m1 of cocaine 6%, 1m1 of 8 Yo sodium bicarbonate, 1m1of 1% adrenaline and 6 m1 of normal saline) shared between both nostrils in this position. The anaesthetist is consulted about the administrationof this sympathomimeticsolution.Duringscrubbingup,the patient is left in this position while being transferred to the theatre, so that he/she is in this position for several minutes. The pillow is only then removed and a head ring placed. The skin and nostrils arecleaned with aqueous chlorhexidine and head towels are positioned overlapping symmetrically in the midline with a towel clip placed in the midline abovethehairline. The head should be slightly flexed and it is worth checking that the patient’s body is positioned symmetrically on the table. The philtrum of the upper lip, the upper incisors and the chin should all help in locating the midline. Symmetry is essential in the positioningof the patient, the anaesthetic tube and the towels, and in the surgery. Vestibular hairs are removed if they are long or if there is any tip work. This is done using curved scissors wiped with the paraffin gauze which will be used as a dressing at the end. This helps the hairs to stick to the scissors and allows them to be wiped off without straying everywhere. Intranasally small submucosal blebs of 2% lignocaine with 1:80 000 adrenalineare placed alongthelateral edge of thereturning of the upper lateral cartilages and along the mucocutaneous junction either side of the septum. If a marginal incision is required, small amounts are also placed just distal to the margin of the lower lateral cartilages. Small amounts of lignocaine 2% with 1:80 000 adrenaline are then infiltrated either side externally, mid-way between the medial canthus and the nasion under the periostium, being careful to miss the angular vein. Small amounts are also placed mid-way between the medial canthus and the pyriform aperture on the lateral aspect of the nose. The author leaves the Moffett’s solution and does not suck it out unless there is any tachycardia. The patient is tilted 15” head-up.

Preparation

Incision

peratiwe techni

Check the consent form with the patientand review the aims of the surgery with himlher. Following oral intubation, the tube must be fixed in the midline, as otherwise it can significantly distort the soft tissues and cartilages. A packshould beplaced around the cuffed tube. Soft paraffin is placed liberally over the conjunctivato

External osteotomy Bilateral stab incisions 3 mm long are made with a new size 15 blade at the levelof the medial canthusjust above the angular vein in the direction of the relaxed skin tensionlines. These incisions should be just through the skin. Two other incisions should be made mid-way

I 86

Chapter 26 ~nterca~tilaginous incision This is best done with a size 15 blade angled up and outwards in order to ensure that the plane lateral to the upper lateral cartilage is reached (Fig. 26.3). It is best to respect the position of the upper and lower lateral cartilages and to place the incision between them as far as possible although the returning of the upper lateral cartilage may be so marked that this is not possible (Fig. 26.4). This incision may be extended in continuity with a transfixion incision (as long as the feet of the medial crura are left in place on an anterior strut of septum), which will allow access and visibility of the whole dorsum, or may be joined up with a hemitransfixion incision.

Marginal incision Fig. 26.1 External osteotomy.

This should be done with care as a mistake in this area is difficult to rectify. The distal edge of the lower lateral cartilage can be palpated with a blunt instrument and found where vestibular hair finishes. The initial incision should be made relatively laterally where the margin is easily found (Fig. 26.5). While the experienced surgeon can extend the incision medially and down the anterior aspect of the side of the columella to the medial crus, it is safer to follow themargin with sharp, pointed,curved scissors. The assistant can help by placing a dura hook

Fig. 26.2 Medial osteotomy.

between the medial canthus and the pyriform aperture posteriorly on the side of the nose at its base (Fig. 26.1).

Medial osteotomy Frequently there is access to the internal junction of the nasal bones and cartilage when the upper lateral cartilages have been divided fromtheseptum andan osteotomecan be placed directly at this point (Fig. 26.2). If nohump reduction is needed, thenthe osteotome should be placed after an internal stab incision has been made at this point adjacent to the septum. If this is not done, there is a risk of producing a mucosal inclusion cyst.

Fig. 26.3 Cut in the plane just above the upper lateral cartilages in order to maintain as thick a skin layer as possible.

Rbinoplasty and S~ptorbinoplasty I 87 more pp and down than illustrations often show. It is importantto keep this stripintact so that it can be delivered out like a ‘bucket handle’ and the cartilage can be removed in a controlled way under direct vision (Fig. 26.6; see also Fig. 26.13). This incision allows the distal margin to be kept intact and it is far less likely that an excessive amount will be removed or that the tip will be significantly distorted by asymmetrical surgery or scarring.

External rhinoplasty

Fig. 26.4 Intercartilaginous incision.

The incision should be placed just below the lower third of the columella. An inverted ‘V’ or ‘W’ disguises the scar and a ‘V’ can be converted to a ‘Y’ if the columella needs lengthening. The columellar incision is joined to a marginal incision so that the soft tissue can be raised. Traction on the soft tissue helps, with a two-pronged blunt-ended hook, which is replaced by a vein retractor whenthe dissection proceeds on to thedorsum.The superb access which this provides is helpful in the asymmetrical nose or where there is a gross deformity.

Alar-base reduction Theart of this incision is to be symmetrical, asthe slightest difference is very apparent (Fig. 26.7). It is best

Fig. 26.5 Marginal incision.

between the skin and cartilage, thus putting tension on the cartilage, and the margin can be followedunder direct vision.

Cartilage-splitting incision This is far safer than doing a marginalincision if all that is required is a reduction in the bulbosity of the tip. It should be made at least 4mm proximal and parallel to the distal margin. It is easy to cut across the proximal strip of cartilage as the lower lateral cartilage runs far

Fig. 26.6 Cartilage-splittingincision.

I 88

Chapter 26

Fig. 26.7 Alar-base resection.

to makeadiamond-shaped incision whose external point does not extend past the most lateral pointof the alar base; otherwise scarring can occuraround the alarfacial junction, Fig. 26.8 Saw through the nasal bones and not cartilages.

Procedure in stages

‘Dehurnp’ and infracture 1 Intercartilaginous incision (Fig. 26.4). 2 Advance the size 15 blade over theupperlateral cartilages and under the SMAS in a rotatory fashion, raising as thick a layer as possible. A plane over the septum down to the tip of the septum should be made and care shouldbe taken not to cut into the lower lateral cartilages. McIndoe scissors are then placed to help free this plane. It is important not toextend it laterally as the soft tissues play a supportingrole in preventing the nasal bones collapsing when the bones are infractured. 3 AHowarth’s periosteal elevator is used to raise the periosteum off the dorsal aspect of the nasal bones; otherwise sawing frays it. Again it is not elevated laterally. 4 A Bull saw is then introduced and its rounded end placed over the concavity of the nasofrontal junction (Fig. 26.8). The saw, the wristand the arm tothe elbow should be keptinastraight line so that the line of sawing can be clearly seen. As an approximate guide, it is helpful to try and get this straight line to pass through the tip of the nose. Sawing should be restricted to bone; otherwise the upper lateralcartilages can be torn off the bones. After both sides have been done a segment of mobile bone can be felt. 5 The septum and upper lateral cartilages often form two-thirds of the hump andthese are cutoff by a size 15 blade, which is engaged where the saw cutended, is held horizontally and is then swept down in one movement

Fig. 26.9 Reduce the lower lateral cartilages and septum.

through the cartilaginous part of the hump (Fig. 26.9). The mobilised segment is grasped with fine artery forceps, pushed up to free any soft-tissue strands anddelivered. It is pushed upwards in order toreduce the chance of tearing the upper lateral cartilages. The skin is protected from the scalpel by an Aufricht retractor. 6 Bone dust is removed using aZohlner sucker. Oedema is extruded by pressing firmly for 30s; otherwise any irregularity may be missed. ’7 Externalosteotomiesaredonethroughstabskin

Rhinoplasty and Septorhinoplasty incisions using a 2mm chisel. The superior osteotomyis made just below the intercanthal line. Bleedingis reduced if the skin incision is made anterior to the angular vein and if the chisel is advanced on to the nasal bones before retracting thevein and doing the posteriorpart of the osteotomy. The chisel should not go right through the bones but stop just as the bone gives way with an alteration in the tone on chiselling. This not only reduces bleeding but also leaves some bone intact, allowing the bone to undergo a ‘green-stick’ reduction, which is relatively stable. The vertical osteotomyshould be done ‘low’ on the face in order to prevent a step deformity (Fig. 26.10),although this is not the site of the nasomaxillary suture line. 8 The nasal bones should not be reduced until medial osteotomies have been done. It is worth hesitating and thinking about where force should be applied before infracturing (Fig. 26.11). 9 The upper lateral cartilages should be divided from the septum using a size 1.5 blade, hugging the septum, and angled medially. An Aufricht retractor is used to protect the skin. It is important not togo at all laterally; ‘T’ shape, otherwisethe top of theseptumformsa which is far more difficult to reduce incrementally. 10 Medial osteotomy: an osteotome is engaged on to

the distal edge of the nasal bones and tapped gradually, with its leading edge controlled by palpation. It should not be advancedfurtherthantheintercanthal line; otherwise it may enter the anterior skull base. 11 Thenasal bones should be reduced withcare in order to avoid stripping off the periosteum and mobilising them excessively, with the result that they fall inwards (Fig. 26.11). 12 If the bones resist infracture, it is best to check the osteotomies; otherwise the bones may fracture from the site where the osteotomy is incomplete and either a step will be left or, if the rest of the bone is mobilised, the result will be a comminuted, poorly supportedsegment. 13 The top of the cartilaginous septum and upper lateral cartilages should be reduced using Foman’s scissors under direct vision, withthe skin elevated using an Aufricht retractor. The removal of a small amount of septum has a dramaticeffect on the profile and itis wise to reduce this area slowly when first using this technique. Reduction of a bulbous tip

The safest strategy is to resect the superior rim of the lower lateral cartilages via a cartilage-splitting incision, as this method preserves the lower alar rim. A cartilagesplitting incision is made, preserving at least Smm of distal cartilage (Fig. 26.12). The distal rim of the cartilage can be defined by blunt palpation using the handle of a scalpel; it lies in the area where the vestibular hairs stop. The cartilage can be delivered and bucket-handled over long-handled forceps, allowing both sides to be

Fig. 26.10 Keep the lateral osteotomies low.

Fig. 26.11 Think before infracturing the nasal bones.

I 89

Fig. 26.12 Incisions around the lower lateral cartilages.

190

Chapter 26 Closure/dressings Intranasal incisions are best closed using 310 plain catgut. Symmetry in closure is also important in order to avoid the formation of asymmetrical scar tisue. An intranasal dressing of paraffin gauze for 4 h holds the soft tissue in position until haemostasis allows them to be removed. Intranasal oedema should be squeezed out, using firm pressure on a gauze swab. Strips of Micropore 1cm wide are placed over the dorsum. The whole dorsumshould be covered as oedema pressing soft tissue throughany defect may producea permanent line on the skin at the edge of the Micropore. An inverted shield of plaster of Paris is placed over thedorsum and is secured withonestrip of plaster.

Fig. 26.13 Delivery of the lower lateral cartilage.

delivered (Fig. 26.13). Symmetry and the symmetrical resection of the lower lateral cartilages are essential. Vestibular skin should be preserved in order to prevent vestibular stenosis. The alar cartilages are best held using non-toothed forceps (toothed forceps cantear them). More complex tip work may require a marginal incision or an external rhinoplasty.

Thepatient is best nursed 30”head-up in order to minimise tissue oedema. Antibiotic prophylaxis is recommended if there is any free cartilage. The patient can return home after 1 2 h and is warned to expect a little more facial swelling the following morning. The plaster can be painted with correcting fluid prior to discharge in order to improve the appearance. Theplaster is removed after 1 week. Patients are advised that the nose is likely to be partially blocked and run for several days and that the mucus may be stained with blood.

The marginal incision The marginof the lower lateral cartilage can be palpated using the end of a scalpel handle. It is best to make the initial incision just distal to it in order to avoid cutting into it and getting into the wrong plane. Once the edge has been defined, it is helpful to place a dura hook in between the vestibular skin and the cartilage so that tractioncan be placed on them and thedistal edge followed using sharp-ended curved scissors. The medial cruraare defined by makinga very anteriorly based incision at the apex of the nasal rim, just before the septal skin turns on tothe front of the columella. Again, the dura hookallows the correct plane to be defined and the incisions next to the medial and lateral crura can be joined. It is essential that the intermediate crus is not transected otherwise the alar cartilages will be difficult to deliver and define symmetrically, and the healing is likely to be asymmetrical. Various techniques allow the tipto be altered, such as using amattresssuture toapproximate the domes, which removes any bifidity of the tip and produces some tip projection.

1 Infection is unusual but is the commonest early complication. The author advises patients that if they have progressive pain or increasing nasal obstruction they should return, asthese are the most common symptoms associated with infection. 2 The most common ‘complication’ is the surgeon’s dissatisfaction with the cosmetic result, and it is helpful not to relay this to thepatient. Several studies have shown that the patient’s feeling about the result of surgery is often far better than that of the surgeon. Having said this, it is important to address any questionswhich thepatient may have. Patientsare invariably happy when their plaster is removed. It is several weeks later, when all the oedema has settled and some of the scar tissue has formed, that their progress should be reviewed. Should the patient be dissatisfied, it is worth reviewing with them what the aims of surgery were and how well they have been achieved. It may be appropriate tosay that surgery has not achieved what was envisaged. If further refinement is indicated, it is best to wait

Rhinoplasty and S ~ p t o ~ ~ i n o p ~ a 191 sty at least 1 year before revision, as otherwisehealing becomes less predictable. Both the patient and the surgeon have to use self-control, as there is a tendency to return and correct whatever is felt to be unsatisfactory as soon as possible. Some noses poseformidable technical problems. Very fine skin, the underdeveloped nose, the projecting nose, revision surgery and asymmetrical lower lateral cartilages are among some of the more difficult problems to deal with. Itis greatly preferableto anticipate difficulties and seek help than to find yourself out of your depth. If you do not, you may well leave the patient with even more insurmountable problems. 3 Periorbital bruising is commonfollowingosteotomies. It can be minimised by using sharp chisels, not allowing themto go completely through the nasal bones at osteotomy, and by reducing tissue handling. 4 A Polly beakis all too common because therehas been an inadequate reduction of the septum and upper lateral cartilages once the bony hump has been removed. 5 An excessive resection of the lower lateral cartilages will cause a ‘knock-kneed’ effect in the long term. It is best to leave at least 5mm of alar rim. 6 An ‘open roof‘ occursif the hump is removed but the nasal bones are not adequately infractured. This leaves a wide dorsum and the vertical plate of the ethmoid and the nasal bones can be palpated separately. 7 Excessive infracturing of the nasal bones will cause a pinched nose; this can be prevented by retaining some soft tissue and periosteal connection across the osteotomy line and by placing pressure at thecorrect site when the bones are infractured (Fig. 26.11). Alternative methods

A variety of alternative techniquesexist, such as internal osteotomies and using a chisel as opposed to a saw to reduce a bony hump. Many different techniques work, but whichever you choose adherence to the principles outlined above will prove to be more helpful than becoming obsessed with any individual technique. Some surgeons prefer to complete the tip workbefore addressing the hump. The author’s preference is to remove the bony hump first, as this permitsan assessment as to how much of the septum will need to be removed, and this more delicate workcanthen be donewithout being disrupted by the bony work. The same appliesto the tip work. It is possible to reduce the alar cartilages using a non-delivery or retrograde method, everting the caudal end of the cartilage from an intercartilaginous incision. The author finds this to be less controlled, particularly when trying to attain exact symmetry.

There is a difficulty with correcting a septal deformity as part of a rhinoplasty. If the septum is freed from the upper lateral cartilages, this will remove an important part of its support, especially if there has been resection or mobilisation of theseptum. Much of this section focuses on how to avoid problems when this situation arises. When the septumis bent and this is visible externally, it can either be removed, refashioned and replaced, or the deviation can be disguised with a free cartilage graft on the other side in order to provide symmetry. If the whole cartilage is removed and replaced, then it should be fixed on to the maxillary spine and the profile restored by supporting it in at least one other site-the maxillary crest or vomer if there is enough height in the cartilage graft-or by suturing it to the vertical plate of the ethmoid if it abuts it. A far safer strategy is to mobilise the septum in situ, refashion it as much as possible, leave it connected to either one of the upper lateral cartilages (it can be released from the upper lateral cartilage on the side it is bent towards) or to the vertical plate of the ethmoid and stabilise it in the midline onthe crest and in the columella. The appearance is then reassessed and any remaining asymmetry can be disguised by shaving the moreprominent side or by placing aslither of free cartilage graft on the other side. Onlay grafts can be added if necessary, but these are best left untilthe septumhas been reconstructed as much as possible; otherwise the nose tends to be broad. An intact dorsal strut in continuity with an anterior rim of cartilagepositioned onthe maxillarycrest is needed to maintain the profile of the nose as well as the functional support of the nasal valve. Any mobile anteriorstrut requiresanchoringtothenasalspineand stabilising in a columellar pocketwith at Least two mattress sutures of PDS or Vicryl. If there is collapse or dislocation of the dorsal cartilage, then a septoplasty technique with suturing of the fractured edgesisneeded. Figure-of-eight suturesare placed across the fracture line, with the cross of the ‘8’ being between the fractured segments in order to prevent them from overriding one another. Splints may be needed to help stabilise the fracture; these should be left for 10 days with antibiotic cover. It is best to remove a minimum amount of tissue, as any cartilage is likely to be useful for support andif any further reconstruction is required at a later date.

192

Chapter 26

Approaches to the septum

Theapproaches categories.

to theseptum

fall intotwo

main

Limited mobilisation of the septum

This isused primarilyfora bend withintheseptum which is not apparent externally. It can be approached through a Killian’s incision 4-5mm behind the mucocutaneousjunction,which will leave anintact strut of septum (the correct subperichondrial plane is easily found here, whereas the perichondrium is much moreadherentmoreanteriorly),or, if it lies more anteriorly, via a hemitransfixionincision on the anterior end of the septum, leaving one side of the septal covering intact. Extended dissection of the septum

This is used where there is an anterior dislocationof the septum off the maxillary spine which extends posteriorly off the maxilla and vomer, or where there is a vertical loss of height to the septal cartilage or a bend within the cartilage whichis visible externally. It is best to elevate themucoperichondriumfrom at least the concave side and often from both sides. Thiscan be done through an incision made on the anterior end of theseptum if it is dislocatedanteriorly (effectively a hemitransfixion incision onthe side of columellar dislocation). Getting a good result

Whether replacing the cartilaginous septum or using a graft from the vomer, pinna or costochondral cartilage, there are four principles which will help in getting a good functional and cosmetic result.

1 AA adequate height and length of cartilage are needed (28mm high, 24 mm long). 2 Two points of fixation (see below)arerequired in order to prevent the cartilage from rotating backwards with a loss of supratip support. 3 A broad-spectrum antibiotic with anaerobic cover is required with any free cartilage graft. 4 Thepoints of fixation (if thereare less thantwo natural ones remaining) should be made with a longlasting but resorbable suture, such as PDS or Vicryl. Points of fixation of the septum l Overlap between the upper lateral cartilages and the nasal bones. 2 Inferior support from the vomer and maxillary crest. 3 Anterior support on the maxillary spine. 4 Suspension from the upper lateral cartilages. 5 Posterior supportfromthe vertical plate of the ethmoid. Mattress sutures to hold the anterior end of the septal cartilage in a midline columellarpocket will provide some soft tissue support, but this cannotbe regarded as a primary anchoring point.

Acknowledgements My thanks to my teacher Mr T.R. Bull, and to Linden Cochrane for his help with the illustrations.

Further reading Aiach G & Levignac J (1991) Aesthetic Rhinoplasty, 1st edn. Edinburgh, Churchill Livingstone. Krause CJ, Mangat DS & Pastorek N (1991)Aesthetic Facial Surgery, 1st edn. Philadelphia, JB Lipcott. Tardy ME& Brown RJ (1990)Surgical Anatomy of the Nose, 1st edn. New York, Raven Press.

Functional Endoscopic Sinus Surgery VIJAY K. ANAND AND M A R K J. GLASGOLD

introduction Theintroduction of endoscopes in sinussurgeryhas brought about a revolution in the approach to surgery of theparanasal sinuses. Thistechnical achievement has been critical in the evolutionof a functional philosophy of sinus surgery, which was introduced by Messerklinger (1978) and Wigand (1981). The procedure was further refined by Stammberger (1986) and Kennedy (1986). Thegoal of this surgeryis to return the chronically inflamed nose andparanasal sinuses to a normal functioning state through conservative surgery rather than completely exenterating the nasal and sinus cavlty. The physiological basis of functionalsinussurgery rests on the concept of the ostiomeatal unit being the central area of the mucociliary clearance mechanism of the nose and paranasal sinuses and the site of recurrent sinusitis (Proctor,1966). Eradication of ostiomeatalunit disease withadequateventilationimprovesthe drainage of the inflamed sinuses andthis will allow resumption of mucociliary clearance and return of nearnormal physiological function (Wigand et al., 1978).

Relevant anatomy Theethmoidalbone is asymmetricalcruciatebone which is bordered by theorbitslaterally,thefrontal bonesuperiorly andthesphenoidboneposteriorly. Inferiorly, the perpendicular plate of the ethmoid contributes to the nasal septum. The crista galli lies in the midline superiorly and the cribriform plate, with the fovea ethmoidalis, forms the horizontalpart of the bone terminating in thelaminapapyracea,a delicate bone which separates the nasal cavity from the orbit. Olfac-

tory nerve fibres are transmitted through the cribriform plate into the anterior cranial fossa. The bony ethmoidal labyrinth consistsof 7-1 1 air cells in a pyramidal shape, measuring 4-5 cm in length and 2.5-3 cm in height. The basal lamellae are horizontal shelves of bone attaching the middle and superior turbinate to the medial surface of the lamina papyracea. The ground lamellae are thin shelves of bone separating the anterior and posterior ethmoid cells. The drainage of the anterior ethmoidal system is into the middle meatus, whereas the posterior system drains into the superior meatus at its anterior recess. The lateralnasalwall is formed by theethmoidal bone, including the superior and middle turbinates and theindependentinferiorturbinate (Fig. 27.1).The nasolacrimal duct opens into the inferior meatus at the junction of the lateral wall and tlfe vault of the meatus, usually 3-4cm from the nares. The middle turbinate is an elliptically shaped structure whichis attached superiorly to the lateral aspect of the cribiform plate and is supported laterally by the basal lamellae to the lamina papyracea. The middle turbinateis normally attached to the lateral wall with a concavity laterally. When this curvaturedemonstratesaconcavity medially it is referred to asaparadoxicalcurvature.The middle turbinate may contain air cells and this is referred to as a concha bullosa. The hiatus semilunarisis located in the middle meatus (Figs 27.1 and 27.2). Anterior to it lies theuncinate process and posteriorly the ethmoid bulla. The uncinate process is a thin bony structure covered with mucosa arising anteriorly from the posteromedial border of the nasolacrimal duct. The infundibulum houses the ostium of the maxillary sinus. It is the anterior-most part of the anterior ethmoidal cells, bordered by the uncinate

Fig. 27.1 Lateral nasal wall-sagittally sectioned cadaver.

antral wall and opens either posteriorly or inferiorly to the free edge of the uncinate process. The ostiomeatal unit is the area of the middle meatus which is bound laterally by the inferomedial surface of the orbit, medially by the middle turbinate, anteriorly by the infundibulum and posteriorly by the ethmoid bulla (Fig. 27.3). Anatomicalvariations in theostiomeatal unit can predispose patients to sinusitis.A concha bullosa or a paradoxically curved middle turbinate may

Fig. 27.2 Endoscopic view of ostiomeatal unit.

process medially, the lamina papyracea laterally,superiorly by thehiatus semilunaris andethmoid bulla and inferiorly by the maxillary sinus. The frontonasal duct usually opens at the apex of the hiatussemilunaris. The frontonasaldrainagemayoccasionallydrainintothe recessus terminalis or the middle meatus. The maxillary sinus ostium is located anterosuperiorly on the medial

Fig. 27.3 Ostiomeatal unit-coronally

sectioned cadaver.

~unctionalEndoscopic Sinus Surgery occasionally narrow the ostiomeatal channel. The free posterior edge of the uncinate process may be directed medially, laterally or anteriorly, producing obstruction. Pneumatisation of the roof of the maxillary sinus can displace the uncinate process medially (Haller cell). A large ethmoid bulla or a nasal septal deviation will also cause obstruction at the ostiomeatal unit. The sphenoidsinus is located posterior to the ethmoid system and drains into the sphenoethrnoidal recess (Fig. 27.4). The sphenoid sinus is usually a pair of sinuses separated by a bony septum and the sinus ostium opens on its anterior inferior wall. Impressions of the carotid artery and optic nerve can often be visualised on the lateral walls of this sinus (Fig. 27.5).

Fig. 27.4 Sphenoid sinus-sagittally sectioned cadaver.

135

The nasal cavity is lined with a pseudostratified ciliated columnar epithelium containing basal cells, columnar cells, which bear microvilli and cilia, and goblet cells, which form mucoussecretions. Nasal mucous secretions serve to move protective particles to local infections, transport noxious elements out of the nose and aid in humidification and olfaction. The mucus is made up of a sol and a gel layer. The cilia beat in the thin preciliary layer, propelling the thicker overlying mucus. The activity of the cilia is theprimary mechanism of mucus transport in the paranasal sinuses. Meserklinger (1967) has shown that in the maxillary and frontal sinuses the mucociliary clearance is directed towards the ostia. This pattern appears to be unaffected by secondary drainage sites, such as inferior meatal antrostomies. In the maxillary sinus, mucociliary flow originates on the floor and radiates up along the sinus walls to reach the ostium. In the frontal sinus, mucociliary clearance proceeds up the septal wall to the roof of the sinus and then laterally along the roof and medially along the floor to the ostium. On the right this flow is clockwise and onthe left anticlockwise. Blockage of the middle meatus,due to mucosal inflammation following infection of the anterior ethmoidsinuses or as a result of an anatomical variation, results in a ventilation block and an accumulation of secretions in the secondarily affected major sinuses-the frontal, maxillary and ethmoidal sinuses.

1 Recurrent sinusitis, with stenosis of the ostiomeatal unit, which has been refractory to medical treatment. 2 Chronic hyperplastic sinusitis with obstructive nasal polyposis. 3 Chronic sinusitis with mucocele formation. 4 Fungal sinusitis in patientswith diabetes or in immunocompromised states. 5 Diagnosis of neoplasm in the nasal cavity and paranasal sinuses. 6 Orbital cellulitis/abscess unresponsive to medical therapy.

Fig. 27.5 Endoscopic view of sphenoid sinus.

Nasal endoscopy is the ideal instrument for preoperative evaluation of the patient with recurrentsinusitis. The 0"

196

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and 30"4-mmnasal endoscopes would be themost frequently used instruments to performadiagnostic nasal endoscopy. The 30" and 70" endoscopes may be useful in visualising the lateral wall structures, such as the ostiumof the maxillary sinus and hiatus semilunaris. At times the nasal passages may not accommodate the 4-mm endoscopes, and a 2.7-mm endoscope may be used when the passage is narrow or in the paediatric evaluation of sinsusitis. In order to examine the nasal cavity, the area is first topically decongested with 0.25 % neo-synephrine solution or 3% ephedrine and then anaesthetised with topical 4% xylocaine. The nasal endoscopicexamination should be performed systematically on all patients and the findings recorded. Initially the 0" endoscope is introduced into the nasal cavity and then passed along the floor of the nasal cavity to observe the inferior turbinate, the inferior meatus and the septum. The nasopharynxis visualised at theposterior aspect of the nasal cavity, where thetorustubarius, fossa of Rosenmuller and Eustachian tube orifice are also inspected. The ostiomeatal unit is next examined carefully and this can be facilitated by applying a 4% cocaine or xylocaine solution-soaked cotton pledgets in the middle meatus. The 0" endoscope is passed between the middle an.d inferior turbinate and then rolled under the posterior end of the middle turbinate.Theendoscope is then withdrawn, identifying the bulla ethmoidalis,natural ostium of the maxillary sinus, hiatus semilunaris, frontal recess and uncinate process. The sphenoethmoid recess is identified by passing the 0" endoscope between the middle turbinate and the septum. The sphenoid sinus ostium lies posterior to the middle turbinate and lateral to the septum. Radiological assessment

CT scanning is performed after acute exacerbations of sinusitis have been satisfactorally'treated in order to demonstrate the underlying cause of disease and not the secondary mucosal changes. CT scans demonstrate changes deep to theostiomeatalunit which arenot visible endoscopically and provide a useful surgical and anatomical imaging of the extent of the disease. The CT scan examination should be performed in both the axial andcoronal planes, withsatisfactory bone windows (Zinreich et al., 1987). The CT scan shouldprovide specific anatomicalinformation of thefrontal sinus, frontal recess, uncinate process, infundibulum, maxillary sinus and ostium,ethmoid bulla, sinus lateralis, posterior ethmoid sinus cells, sphenoethmoid recess and sphenoid sinus. Each sinus is evaluated for the extent of

mucoperiosteal thickening and patency of its communication with the middle or superior meatus. Perhaps the most crucial role of the CT scan is in helping the surgeon anticipate anatomical variations in the roof of theethmoidal and sphenoid sinuses and evaluating the integrity of the bony walls of the orbit. A critical relationship to determine preoperatively in patients undergoing functional endoscopic sinus surgery (FESS) is the level of the roof of the ethmoid sinuses in comparison with the crista galli. The cribriform plate lies 4-7 mm below the ethmoid roof in 70% of patients; however in 20% of patients it can lie 12-17mm lower than the roof. In only 10-20% is the roof at the same level asthecribriform.Dural dehiscence can also be delineated clearly on a CT scan in thepreoperative evaluation. Preoperative assessment

It is importantto assess preoperatively any bleeding disorders that the patient may have and these should be adequatelytreatedprior to surgery. All patientsare instructed nottotake any medications which are prostaglandininhibitorsfor at least 14 days prior to surgery. Patients with active sinusitis shouldnotundergo endoscopic sinus surgery while they are acutely infected. Appropriate medical therapyshould be instituted to bring them to a quiescent stage and they can then undergo definitive surgical therapy. Acute asthmatics, particularly those with the triad, referred to as Sampter's syndrome, of asthma, aspirin sensitivity and nasal polyposis, should be evaluated with pulmonary function tests and treated preoperatively to stabilise their mucous membranes. Steroids may be necessary and the dosage is planned according to the acuteness and duration of the asthma. If oralsteroidsare initiated preoperatively, they should be continued during the operative and postoperative period to avoid the, side-effects of a sudden surge of increased levels of histamine, prostaglandins E, and E2 and slow-reacting substance (SRS), which are seen in circulationduring surgery and which may precipitate an asthmatic episode in the postoperative period.

Classification of functional endoscopic sinus :surgery: Anand and Panje system Various staging systems have been developed for staging sinus disease for FESS (Kennedy, 1992). TheAnand and Panje (1993) staging system was developed in order to

FunctionalEndoscopic Sinus Surgery

197

determinetheextent of FESS for varying degrees of sinusitis. This staging system is based on the extent of disease involvement of the sinuses, which is documented by nasal endoscopy and CT scan evaluation. This system is practical and has proved to be extremely useful in clinical practice. Type I (Fig. 27.6)

Extent of disease

1 Isolated ostiomeatal thickening of mucous membrane at the infundibulum. 2 Patent maxillary sinus ostia without maxillary sinus membrane thickening and/or cysts. 3 Unsuccessful prior inferior maxillary sinus antrostomy and/or antrotomy with irrigation. 4 Prior septoplasty/adenoidectomy with continued paranasal sinus symptoms. 5 Anterior agger nasi cell infection presenting as dacryocystitis or erythema of the medial fornix of the eye.

(a)

Surgery Nasal endoscopy and uncinectomy withorwithout agger nasi cell exenteration. Type II (Fig. 27.7) (b)

Extent of disease

1 Extent of disease as per type I with ostiomeatal thickening of mucous membranes with evidence of anterior ethmoid sinus opacification, including obstruction at the infundibulum. 2 Limited frontal sinus recess disease.

Fig. 27.7 CT scan (a) coronal and (b)axial view of type IT disease.

Surgery Nasal endoscopy, uncinectomy, bulla ethmoidectomy, removal of sinus lateralis mucous membraneand exposure of frontal recesdfrontal sinus. Type 111 (Fig. 27.8)

Extent of disease

1 Extent of disease as per type 11 with evidence of maxillary sinusitis as evidenced by membrane thickening and/or opacification. 2 Stenotic or oedematous maxillary sinus ostium. Surgery Fig. 27.6 CT scan coronal

view of type I disease.

Nasalendoscopywithtotalanteriorethmoidectomy and middle meatal maxillary antrostomy.

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Chapter 27

(a)

Fig. 27.8 CT scan (a)coronal and (b)axial view of type I11 disease.

(b)

(a) Fig. 27.9 CT scan (a) coronal and (b)axial view of type IV disease,

Type IV (Fig. 27.9)

Type U (Fig. 27.10)

Extent

Extent of disease

of disease

1 Extent of disease as per type I11 withtotalethmoidal involvement. 2 Nasal polyposis with extensive ethmoidal and maxillary ' sinus disease unresponsive to medical therapy. 3 Priortype I or type I1 FESS without response or progression of sinus disease. Surgery

Nasal endoscopy withtotalanteriorandposterior ethmoidectomy and middle meatal endoscopic antrostomy.

1 Extent of disease as per type IV with evidence of sphenoid sinusitis. 2 Pansinusitis and rhinitis. Surgery

anterior endoscopy Nasal total with and posterior ethmoidectomyand middle meatal endoscopic antrostomywithsphenoidotomy and stripping of mucous membrane.

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FunctionalEndoscopic Sinus Surgery

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(a) Fig. 27.10

CT scan (a) coronal and (b) axial view of type V disease.

FESS can be performed under local or general anaesthesia. The advantages of local anaesthesia are in themaintenance of excellent haemostasis and preservation of sensation, which helps to avoid accidental penetration of the orbit, base of the skull, roof of the ethmoidal bulla and region of the optic nerve. General anaesthesia offers efficiency, reduced pain,controlledventilation, which is especially important for asthmatics, and avoidance of aspiration.

1 Position: the patient is placed in the supine position at 1.5"reverse Trendelenburg and 4% cocaine pledgets are placed in the middle meatus. 2 Local anaesthesia: if septal surgery is to be performed, then 1% xylocaine with 1:100 000 adrenaline is injected in the mucoperichondrial plane. This same injection is also used to infiltrate the region of the vascular strip in the middle meatus, which is just anterior to the uncinate process, and at the attachment of the middle turbinate. The middle turbinate should also be injected in order to avoid bleeding during the procedure. 3 If the nasal septuminterferes with adequate visualisation of the ostiomeatal unit, a septoplasty or submucous resection of the septum should be performed prior to endoscopic sinus surgery. 4 The initial stepintheethmoidectomy is to reflect medially the middle turbinate, using a Freer elevator. An infundibulotomy is then performed, using a sickle knife or a Freer elevator (Fig. 27.1 1).In order to accomplish this, the uncinate process should be defined by palpa-

Fig. 27.11 Endoscopic view (0' endoscope) of infundibulotomy revealing medial displacement of the uncinate process.

tion,the sickle knife is inserted immediately anterior and inferior to the insertion of the middle turbinate and the incision is then carriedinferiorly towards the natural ostium of the maxillary sinus. 5 The uncinate process is then removed with a Blakesley-Wilde forward-biting forceps, using a gentle grasping and twisting motion. This will expose the base of theinfundibulum and theanterior wall of the ethmoidal bulla (Fig. 27.12). The openingof the maxillary sinus ostium is usually well visualised at this point. 6 The ethmoidal bulla is next exenterated, if indicated, by penetratingwitha Blakesley-Wilde forceps at its

zoo

Chapter 27' sphenoid sinus (Fig. 27.14). Superior and lateral areas are in close proximity to the optic nerve and carotid artery and the surgical procedures should not be carried out in these areas (Fig. 27.15). The lamina papyracea should be visualised well and penetrationshould be avoided (Fig. 27.16). The anterior and posterior ethmoidal arteries should be identified and preserved in their bony canals (Fig. 27.17). If mild bleeding interferes with visualisation, neurosurgical cottonoids soaked in

Fig. 27.12 Endoscopic view (0" endoscope) following uncinectomy revealing the ethmoid bulla and frontal recess.

Fig. 27.14 Endoscopic view (0" endoscope) of sphenoid sinus ostium (arrows).

Fig. 27.13 Endoscopic view (0" endoscope) following ground lamella penetration revealing posterior ethmoidal cells.

inferiomedial aspect. Posterior to the bulla, thenext anatomical landmark encountered is the lateral attachment of the middle turbinate, the ground lamella (Fig. 27.13). This relatively dense bone is removed with the upbiting straight Blakesley-Wilde forceps, which allows entry into the posterior ethmoidal cells. '7 Chronically inflamed and hyperplastic mucous membranes in these cells should be exenterated by an of the inferomedial approachtowardstheostium

Fig. 27.15 Endoscopic view (30" endoscope) of lateral wall of sphenoid sinus.

FunctionalEndoscopic Sinus Surgery

Fig. 27.16 Endoscopic view (30" endoscope) of middle meatus revealing penetration of the lamina papyracea with exposure of orbital fat.

Fig. 27.17 Endoscopic view (30"endoscope) of frontal recess revealing the anterior ethmoidal artery.

1:l000 adrenaline can be applied topically to obtain haemostasis. 8 In patients with maxillary sinus disease or stenosis of the maxillary sinus ostium,the surgical procedure should be aimed at enlarging the ostiumof the maxillary sinus. The ostium is located at the level of the anterior inferior edge of the middle turbinate (Fig. 2'7.18). Palpation of the lateral wall of the nasal cavity produces a

201

Fig. 27.18 Endoscopic view (0" endoscope) of the ostiomeatal unit revealing location of the maxillary sinus ostium with a BlakesleyWilde forceps.

small air bubble from the ostium. At this stage of the operation, visualisation using a 30" endoscope is often preferable to a 0" endoscope. After visualising the ostium, a small carved suction tubemay be used to enter the sinus in an inferior direction. The endoscopic scissorsare used to make precise cuts posteriorly at the superior and inferior extent of the ostiumand a straightbiting forceps is used to remove the incised tissue. This enlarges the ostium and allows the insertion of a backbiting forceps into the ostium. The ostium is enlarged anteriorlywithcare, and damage to the dense bone anteriorly in thearea of the lacrimal ductshould be avoided. Infected secretions and polypoid disease of the maxillary sinus mucosa can be removed, but hyperplastic mucosa should be preserved in the anticipation that it will return to normalphysiological function with adequate ventilation. 9 In a poorly suspended middle turbinate, it may be necessary to amputate the anterior third of the middle turbinate.This may, however, lead to complaints of nasal pain or discomfort in extreme cold or windy conditions.

Postoperative management 1 In the postoperative period, diligent endoscopic care should be carried out with regular debridement. These patients should be examined on a weekly basis for the first 4 weeks in order to ensure satisfactory re-

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Chapter 27

epithelialisation. Dried blood and crustsare removed endoscopically and the cavity lubricated with antibiotic ointment. 2 Synechiae between the middle turbinate and lateral nasal wall areacommonpostoperativeproblem. In order to avoid this problem,non-adherent Gelfilmis inserted between the middle turbinate and lateral nasal wall at the end of the surgery. This splint is removed after 2 weeks, or when satisfactory healing has occurred. 3 Synechiae should be lysed if they develop, and this can be done with topical 4% cocaine anaesthesia and a Freer elevator in the postoperative period.

dureextendsintothe middle and posteriorethmoid sinuses, where the medial rectus and superior oblique muscles are in close proximity to the lamina papyracea. Muscle injury will manifest itself postoperatively as limitation in ocular motion or as diplopia.If this occurs, it is necessary to determine if it is due to muscle injury or entrapment. The forced duction test may help to confirm the diagnosis. The entrapmentof muscles should be corrected immediately upon diagnosis by an external medial canthal approach. Ophthalmological consultation is advisable.

Complications

This is an acute emergency, which can lead tononreversable optic nerve injury and permanent blindness. Diagnosis is made by observing a tense proptotic globe. Treatment consists of immediate lateralcanthotomy and, if necessary, transection of the lateral canthal ligament. The patient should also receive dexamethasone 0.5 mglkg and mannitol 1.Oglkg. These manoeuvres may allow time to perform an external orbital decompression andcontrol of bleeding. Ophthalmological consultation is important for accurate evaluation of vision and postoperative follow-up.

The complications of FESS can be classified for convenience into an immediate and a delayed group. The immediate complications of endoscopic sinus surgery will include epistaxis, orbital emphysema, injury to the extraocular muscles, orbital haemorrhage and cerebrospinal fluid (CSF) rhinorrhoea (Stankiewicz, 1989). Epistaxis

This is the most common complication and is usually due to trauma to a vessel or systemic coagulation problems. Direct control, using bipolar electrocautery and nasal packing, is the mainstay of treatment. If haemorrhage persists dueto systemic coagulopathy,nonadherent nasal packing is helpful in controllingthe bleeding. Injury to the periorbita

Injury to the periorbita during endoscopicsinus surgery is not in itself a significant problem, but can lead to the development of subcutaneous emphysema, orbital cellulitis and abscess. Possible violation of the bony orbit can be detected intraoperatively by palpating the eye while examining the ethmoid sinus. Bulging tissue intotheethmoid sinus indicates a bony dehiscence. Postoperatively these patients are instructed notto blow their nose and are placed on oral antibiotics. The eye is carefully examined for limitationof range of movements or changes in visual acuity. Orbital emphysema will usually resolve spontaneouslywithina week without further sequelae. Damage to the extraocular muscles

Damage to the extraocular muscles during endoscopic sinus surgery may occasionally occur when the proce-

Orbital haemorrhage

Cerebrospinal fluid leak

This is usually a result of a dural dehiscence and penetration, which may result from a cribriform plate fractureduring medialisation of the middle turbinateor from a direct injury to the roof of the ethmoid sinus. Direct injury usually occurs at theposterior aspect of the frontal recess or posteriorly at the sphenoethmoidal recess. If the leak site can be identified, a graft of nasal septal or buccal mucosa or temporalis fascia is positioned over the leak site and held in place with iodoform-bacitracin-impregnated gauze and Gelfilm. The packing is left in place for 2 weeks and the patient is placed on antibiotics, fluid restriction (1500ml/day), Diamox(250mg bid.) and astool-softenerandcautioned not to strain or blow the nose. For larger CSF leaks, lumbar spinal drainage may be necessary to decrease the CSF pressure in order to facilitate closure of the leak. Delayed CSF leaks may occur and these require CT scan evaluation and metrisamide or radioactive indium-tagged red blood cell (RBC) studies to identify the site of the leak. If a dehiscence or fracture is identified, it can be repaired endoscopically at the same sitting. In the majority of patients with small CSF leaks, the wound healing from ethmoidectomy may produce early and permanent closure of the CSF leak.

FunctionalEndoscopic Sinus Surgery Nasal crusting

Thiscan be extremelybothersomeforsomepatients postoperatively and adequate humidification of the nasal cavity is important inpreventingcrusting.Nasal saline irrigations and steam inhalation are useful and shouldalways be followed by application of an oilbased cream for early epithelialisation.

References Anand VK & Panje WR (1993) Endoscopic sinus surgery indications, diagnosis, and technique. In: Anand VK & Panje W R (eds) Practical Endoscopic Sinus Surgery. New York, McGraw-Hill, pp. 78-80. Kennedy DW (1986) Functional endoscopic sinus surgery: technique. Arch. Otolaryngol. 11 1, 643-9. Kennedy DW (1992) Prognostic factors, outcomes and staging in ethmoid sinus surgery. Laryngoscope 12 (Suppl. 102), 1-18.

203

Messerklinger W (1967) Onthe drainage of the normal frontal sinus of man. Acta Otolaryngol. (Stockh.) 673, 176-81. Messerklinger W (1978) Endoscopy ofthe Nose. Munich, Urban and Schwarzenberg. Proctor DF (1966) Theparanasal sinuses and pharynx. In: Walters W (ed.) Lewis-Walters Practice of Surgery. Hagerstown, MD Prior, pp. 1-37. Stammberger H (1986) Endoscopic endonasal surgery: new-concepts in treatment of recurring sinusitis. Part I and 11: Anatomical and pathophysiological considerations and surgical technique. Otolaryngol. Head Neck Surg. 94, 143-56. Stankiewicz J (1989) Complications of endoscopic sinus surgery. Otolaryngol. Clin. North Am. 22 (4), 749-58. Wigand ME (1981)Transnasal ethmoidectomy under endoscopic control. Rhinology 19, 7-15. Wigand ME, Steiner W & Jaumann MP (1978) Endonasal sinus surgery with endoscopical control: from radical operation to rehabilitation of the mucosa. Endoscopy 10, 255-60. Zinreich SJ, Kennedy DW & Rosenbaum AE (1987) CT of the nasal cavity and paranasal sinuses: imaging requirements for functional endoscopic sinus surgery. Radiology 163, 769-75.

gery for Choanal Atresi DAVID W. MORGAN

Relevant anatomy Choanal atresia is due to failure of the bucconasal membranes to undergo involution. The atresia may be bony (90Y0)or membranous (10%) and is generally sited in front of the posterior end of the nasal septum. Bilateral atresia normally presentsat birth with respiratory obstruction. Unilateral atresia, normally presents within the first 18 months of life with feeding difficulty and nasal discharge; rarely,unilateralatresiamay be diagnosed in later childhood. Correction of unilateral atresia may be delayed, unless there are feeding difficulties. Preoperative management

A full history and examination must be carried out, as

there is a 70% incidence of other associated congenital anomalies and 30% of patients have the CHARGE association (Morgaa & Bailey, 1990). Thetiming of choanal repair will be influenced by the associated anomaly. Bilateral choanal atresia requires early stabilisationof the oral airway (Fig. 28.1). The diagnosis of atresia may be inferred by simple clinical tests of airway patency, such as passing a soft, red-rubbercatheter,observing misting on metal a spatula, auscultation of the nares or using a wisp of cotton wool. Axial scanning is theinvestigation of choice. Intheinfant,sedation or generalanaesthetic (GA) maybenecessary to obtain good-quality scans. Carefulpreparation, using vasoconstrictordrops and nasal suction, is essential if high-quality images of the atresia are to be obtained.

It is importantto remember, in thenewborn,the close proximity of thebasisphenoid,which is still cartilaginous in part and separates the nasalcavity from intracranial contents. The abnormality of the posterior choanae is usually a thin bony atresic plate or mucous membrane. However, the posterior endof the septum is usually thickened and thepterygoidplates medially placed (Fig. 28.2).

Operative technique There are two maintechniquesforthecorrection of choanal atresia. The transnasal approach is the method of choice, whilethe longer transpalatalapproach is normally reserved for the older child. Preparation

Both techniques are performed under general anaesthesia, with the child intubated with an armoured flexible endotracheal tube; a sandbag is positioned under the shoulders and a Boyle-Davis mouth gag positioned to allow inspection of the postnasal space. Transnasal approach

Procedure in stages

1 Thepostnasal space is examined using a 120" Hopkin's rod telescope, following soft-palate retraction; this enables the abnormalityof the posterior choanaeto be visualised. Theanteriornaresarealsoexamined, following the useof vasoconstrictor drops and gentle

Surgery f o r Choana1 Atresia

205

cutting burr is used. Care must be taken to avoid damaging the alar margins; this may be achieved either by using an aural speculum to protect the alar margin, or alternatively by covering the shaft of the burr with 12 French-gauge Portex tubing. During drilling, the postnasal space rnay be visualised, using a 120" Hopkin's rod telescope. The oral surface of the palate must also be observed for signs of mucosal blanching. Initially the posterior end of the septum is thinned; a 5mm diamond burr is then introduced to enlarge the posterior choanae. Care must be taken to avoid exces-

Fig. 28.1 Oral airway maintenance in bilateral choanal atresia.

nasal suction. This inspection rnay be carried out using either a headlight or, ideally, a 0" Hopkin'srod telescope. 2 Once the diagnosis is confirmed, the atresic plate is perforated, using a curved urethral sound, care being taken not todamage the postnasalspace. If the atresia is membranous, subsequent dilatations can be carried out until a size 18 French-gauge dilator can be introduced with ease. One should avoid forcing the dilator, as this may well result in basisphenoid fractures. 3 In bony atresia,thechoanaeare enlarged using a diamond drill introduced through the anterior choanae under direct visualisation (Fig. 28.3). Initially a 2mm

Fig. 28.3 Operative position for correction of choanal atresia. Note aural speculum protecting alar margin.

Fig. 28.2 CT scan demonstrating bilateral choanalatresia. Note thickening of posterior septum.

206

Chapter 28 nasal dilatation may be all that is required. Occasionally revision surgery may be indicated. Complications

Fig. 28.4 Portex stent with suture.

sive bone removal superiorly on the basisphenoid and laterally, where damage to thegreaterpalatine and sphenopalatine arteries may occur. The posterior end of the septum is finally removed over a distance of 7mm, thus enlarging the posterior choanae. 4 The resulting choanae are then stentedusing a size 3.5 Portex endotracheal tube (ET), cut to the appropriate length and shape (Fig. 28.4).The length of stent is judged by introducing a Portex tube down the anterior nares until it is just visible in the postnasal space. A 3mm section of the tube is then removed to allow nontraumatic positioning across the columella and the introduction of a catheter within the tube lumen for later suction clearance. The stent is then positioned in the nasal cavity and two suction catheters are passed down the stent into the postnasal space, a 1.0 nylon ligature being attached to each end of thesuctioncatheters perorally. The suctioncathetersarethenwithdrawn through the nasal stents, thus allowing the nylon ligature to pass down the inside of each tube around the back of the nasal septum andto be tied over the columella bridge of the stent (Fig. 28.5). The stent is then checked for excessive movement.

There is a 10% incidence of intraoperative complications. Palatal fistulae may occur, following dilatation; these normally heal spontaneously. If fistulae occur following drilling, then operative closure, utilising a mucoperiosteal rotation flap, is usually successful. Postoperative complications occur in 10% of cases, the most common being alar or columella ulceration, due to the stents being fashioned incorrectly. This may well lead to significant cosmetic deformity. Stent reinsertion may also be required if it becomes displaced anteriorly due to a deficient posterior septum. ~ranspalatal correct9

Position

The patient is positioned as in the transnasal correction, utilising a Boyle-Davis gag. The operating surgeon is positioned at the head of table, using a headlight for illumination. Incision

The mucoperiosteum of the hard palate is infiltrated, using asuitablevasoconstrictor. A curved incision, starting level with the maxillary tuberosities and medial to .the greater palatine foramen, is carried anteriorly, parallel to the maxillary aveoli (Fig. 28.6). The mucoperiosteum is then elevated, using a Freer elevator, posteriorly to the margins of the bony hard palate. Care must be taken to avoid damaging the greater palatine

Postoperative management

The length of the stent is noted so that the appropriatelength suctioncatheters may be introduced to pass intothepostnasal space. Regular suction is carried out, following instillation of 0.5 m1 normal saline drops on a regular basis. Prophylactic antibiotics are not required, although care must be taken to ensure that columella ulceration does not occur. The stent is removed asanout-patientafter 6 weeks and this is followed by a 2-week course of nasal steroid drops. If a patient subsequently develops signs of nasal obstruction, re-examination under a GA, with subsequent

Fig. 28.5 Stent secured over columella.

Surgery for Choana1Atresia

207

Stenting manage~ent

The stenting management 'is as in the transnasal correction. Complications

The transpalatal approachmay result in restricted palatal growth in the infant and therefore should be reserved for correction of atresias in the older child or adult. The major postoperative complicationis fistula due to breakdown of the mucoperiosteal flap; this may be repaired using a local rotation flap.

Fig. 28.6 Incision for transpalatal repair.

artery. To aid closure themucoperiosteum on the anterior side of the incision is also elevated a very short distance. The mucoperiosteum flap is retracted and a 5mm diamond burr used to remove the bony atresic plate on the involved side. Seven millimetres of the posterior end of the septum is normally removed.

Reconstruction of the posterior choanae is followed by repositioning of the mucoperiosteal flap, using 310 Vicryl sutures.

The advent of the YAG laser, which may be introduced using the Wolfe laser endoscope, is a more elegant way of treatingmembranouschoanalatresia (El-Guindy, 1992). Two alternative approaches for transnasal repair involve the midfacial degloving approach andthe external rhinoplasty approach (Koltai, 1991).

El-Guindy A (1992) Endoscopic endonasal surgery of posterior choanal atresia. JLO 106 (6),528-9. Koltai PJ (1991) Theexternal rhinoplasty for the correctionof unilateral choanal atresia in young children. Ear Nose T h o a t J . 1970 (7), 450-3. Morgan DW & Bailey CM (1990) Current management of choanal atresia. Int. J . Paediatr. Otolaryngol. 19, 1-13.

VALERIE J. LUN

External

ethmoidal The vessels provide an indication of the of level cribriform the plate. Mean distances of 24, 12 and 6mm separate the anterior lacrimal crest from the anteriorethmoidalartery,theanteriorandposterior 1 Frontoethmoidal mucoceles. ethmoidal arteries and the posterior ethmoidal and optic 2 Orbital complications of acute frontoethmoiditis. canals respectively, but the range is considerable. 3 Chronic infection unresponsive to conservative mediThe frontal recess is usually an hourglass narrowing cation and surgery. rather than a true 'duct' opening in the anterosuperior 4 Recurrent polyposis, middle meatus, often lying medial to the ostium of a 5 Access for ethmoidal artery ligation in the treatment suprabullar cell. The opening may be double in 12% of of epistaxis, transethmoidal hypophysectomy, the Caucasian population andmay be impingedupon by dacryocystorrhinostomy,repair of cerebrospinal fluid pneumatisation of the agger region. (CSF) leaks and orbital decompression. For further details of anatomy see chapters on FuncMany of these conditionscan be managed by an tionalEndoscopic Sinus Surgery, LateralRhinotomy endoscopicapproachbutit is not technically possible to and MedialMaxillectomy, and AnteriorCraniofacial use this in all cases. It may also be necessary to employ Resection. an external approach as an emergency procedure if an orbital haematoma occurs during endoscopicsinus surgery. As a consequence, an important rolestill exists for this approach. Preparation

(Lynch-H

1 The operation is performed under general anaesthesia, given via an oral endotracheal tube (ET) with pharyngeal pack. The nasal cavity should be treated with Inmostsituations CT scanning is thepreoperative Moffett's solution in the anaesthetic room and the inciimaging of choice to demonstrate sinus anatomyas well sion line is injected with 1:200000 adrenaline. as pathology. 2 Prophylactic antibiotics are only required if there is evidence of infection. Relevant anato 3 Thepatient isplaced ina reversed Trendelenburg An account of thedetailedanatomy of thefrontoeth-positionwith 1.5" o f head-up tilt. The eyes should be moidal area isbeyond the scope of this book but it is taped or a temporary tarsorraphy performed on the side worth rememberingthevariationinherent in the region. of theprocedure. Thefrontalsinus is absent in 1% of the Caucasian Incision populationandwhenpresentitsconfiguration is unique to each individual. A curved incision is made, beginninglevel withthe Preoperative mana~emen~

208

External Operations on the ~rontoethmoidalComplex

zog

29.3). The vertical lamella of the middle turbinate is preserved if possible as a future landmark unless irretrievably diseased. The sphenoid may be entered under direct vision if necessary. 4 The medial floor of the frontal sinus can be removed and extended laterally as much as needed for removal of pathology (Fig. 29.4).Whether ornot all mucosa is

Fig. 29.1 Incision for Lynch-Howarth approach in medial superior quadrant of orbit. After Rob ei. Smith’s Operative Surgery -Head and Neck (1983). IA McGregor & DJ Howard (eds).

medial canthus, mid-way between the medial canthus and the nasal bridge, and cutting down to bone (Fig. 29.1). This can be extended superiorly under the eyebrow for a variabledistance but care shouldbe taken to avoid division of the supratrochlear vessels and nerve. A Z-plastyhas been recommended by some authors to avoid webbing, but this is rarely a problem with correct positioning of the incision. Procedure 1 The periosteum is incised and elevated with a Freer’s elevator to expose the nasal process of the maxilla, frontal bone and medial wall of the orbit (Fig. 29.2). The periosteum is quite firmly attached to the anterior lacrimal crest andat thefrontonasalandfrontoethmoidalsutures.Careshould be taken not to penetrate it or orbital fat will prolapseintothe surgical field. Similarly the trochlear area should be sharply dissected. The lacrimal sac is elevated from its groove and displaced laterally. 2 The periosteum is dissected from the lamina papyracea. This is facilitated by the use of a malleable copperretractorandribbon gauze soaked in topical adrenaline. As dissection proceeds posteriorly, the anteriorethmoidal vessels areencountered and may be diatherrnied and divided. Rarely, neurosurgical clips are required. Further dissection displays the posterior ethmoidal vessels, which are again divided, bearing in mind that they may be within a few millimetres of the optic nerve. 3 The lamina papyracea can easily be penetrated and the ethmoidal cells cleared, from anterior to posterior, using a Tilley-Henkel or Blakesley-Wilde forceps (Fig.

Fig. 29.2 Periosteum is incised and elevated with a Freer. After Rob ei. Smith’s Operative Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

Fig. 29.3 Ethmoidal labyrinth is exposed by removal of lamina papyracea. After Rob ei. Smith’s Operative Surgery -Head and Neck (1983). IA McGregor & DJHoward (eds).

septum, placed under endoscopic visualisation. Alternatively, if theareacan bevisualised endoscopically at regular out-patient visits, it may be possible to avoid the use of stents altogether. 6 The intersinus septum should be perforated if technicallypossible,even thoughit will only drain thecontralateral side by gravity. The removal of the intersinus septum and the upper nasal septum and the creation of mucosal flaps into the frontal recess have been advocated but have not proved universally successful. Closure

Fig. 29.4 Ethmoidal labyrinth and frontal recess are cleared with Blakesley-Wilde forceps. After Rob & Smith’s Operative SurgeryHead and Neck (1983). JA McGregor & DJ Howard (eds).

removed will depend upon the pathology andindividual philosophy. In many cases all diseased mucosa will need to be removed, except in areas where the pathology has exposed dura. In other circumstances, such as an acute complicated infection, drainage alone may be sufficient. In either case, thefrontal sinus ostium may be obstructed by disease, which should be cleared. However, if any mucosa can be salvaged, it will enhance future patency of this region. Similarly, if any bone can be retained laterally, this will prevent the prolapse of the orbital contents into the frontal recess, which can predispose to obstruction. 5 Maintenance of long-term patency of the frontal recessis one of themajorproblems in sinus surgery. Despite thecreation of a large channel, closure frequently occurs, due to circumferential fibrosis and new bone formation. A considerable variety of strategies have been employed to stent the area, although none have proved infallible. A l-cm-diameter Silastic tube or rolled Silastic sheet are probably the most commonly used (Fig. 29.5). This runs from the sinus into the middle meatus and opens into the nasal cavity. Combining theexternal technique with an intranasal endoscopic approach allows excellent visualisation and more precise clearance of the middle meatus from below. The tube may be fashioned to sit just withinthe middle meatus. The size of the tube ensures that it will stay in place but it canbe held in position by a suture on a small straight needle through the middle turbinate and

The periosteal layer is closed with catgut, paying special attention to the trochlear region, which should be formally reattached to the periosteum of the frontal region with a non-resorbable suture, such as Prolene. Without this the pulley action of the superior oblique may be impaired, although care must be taken not tosuture the muscle tendon itself. The skin is sutured with fine silk or nylon, the eye is washed with saline and chloramphenicol ointment instilled. Significant oedema may occur, which can be diminished with the application of a pressure dressing overnight. st

The sutures should be removed at 4-5 days. The nasal cavity should be cleaned and the patency of the tube checked regularly. This is best done endoscopically. The patient should use regular saline sniffs for the first few weeks after surgery and may require other intranasal

Fig. 29.5 The frontal sinus is drained with a temporary Silastic tube and the intersinus septum is perforated to allow gravitational drainage. After Rob & Smitb’s Operative Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

External Operations on the Frontoethmoidal Complex preparations, dependent on the original pathology. The duration of the tube is uncertain. Three to five months is the average, but it can be left longer if it is not causing any discomfort.

1 Vertical diplopia due to underaction of the superior oblique muscle. This may be temporary, due to rapid decompression of a displaced globe, or permanent, if the trochlea fails to reattach satisfactorily. A prism modification to existing spectacles will often produce adequate correction; rarely, eye muscle surgery is needed. 2 Webbing of the incision. 3 Paraesthesia due to damage to thesupratrochlear nerve. 4 CSF leak may result, either due to exposure of the dura by the pathology or if the mucosa in the region of the cribriform plate or the superior attachment of the middle turbinate is disturbed. The area can be repaired with a free mucosal flap taken from the middle turbinate, free dermal fat or a nasoseptal flap positioned with tissue glue, gelatin (Gelfoam)and sometimes a small Whitehead’s varnish pack. 5 Frontonasal obstruction: this is by far the commonest problem after frontal sinus surgery and may result in recurrence of the original pathologyor mucocele formation many years later.

These are essentially the same asforthe LynchHowarth approach, but transorbital ethmoidectomy is primarily used for access to the orbitalfloor in blow-out fractures and to perform orbital decompression, mainly for thyroid eye disease.

21I

Incision

The incision is made from thelevel of the medial canthal ligament, running one finger’s-breadth below the lash margin of the lower lid in the nasojugal fold and extending no further than the midpoint of the orbital rim (Fig. 29.6). Procedure

1 The incision is made down to bone, dividing the fibres of orbicularis oculi. The periosteumis firmly attached to the orbital rim and requires careful dissection with the Freer’s elevator. 2 As the periosteum is lifted from the orbital floor, the attachment of the inferior oblique muscle is seen in over 90% of individuals and must be dissected off the bone. 3 The lacrimal sac and the nasolacrimal duct are identified medially (Fig. 29.7). Ribbon gauze soaked in 1 :1000 adrenaline and a malleable copper retractor again aid dissection, but special care must be exercised to avoid excess trauma to the duct. The periosteum can be extensively elevated from the orbitalfloor and medial wall as far superiorly as the ethmoidal vessels. 4 In cases of orbital decompression, the floor of the orbit can be removed as far laterally as the infraorbital nerve (Fig. 29.8). The position of this can be identified from that of theinfraorbitalforamenandfromthe bleeding that occursasthe nerve is approached.The bone is initially perforated with a hammer and gouge and the opening enlarged using upcutting bone forceps (e.g. Hajek’s) or Tilley-Henkel forceps. It is possible to remove bone lateral to theinfraorbital nerve by this approach or via a lateral orbitotomy, although the extra axial decompression obtained is only 1-2mm.

CT scanning is again of considerable value in assessing the anatomy as well as the extent of the pathology. A careful orbital assessment is mandatory in any cases where vision is already compromised.

Preparation

This is the same as for the Lynch-Howarth approach.

Fig. 29.6 Incision for Patterson’s approach in nasojugal fold. After Rob c9 Smith’s Operative Surgery-Head and Neck (1983). IA McGregor & DJHoward (eds).

possible to simply stent the floor from below with a Whitehead’s pack or thearea may be reinforced by fascia lata or Silastic sheeting. 8 Blood will drain into the maxillary sinus and nasal cavity butcan be facilitated by the fashioning of a middle meatal antrostomy, which will also help avoid future sinusitis. Closure The wound is closed in layers, with a separate layer of catgut to theorbicularis muscle. Occasionally. nasal packing is required, and postoperat~ve is diminished by the application of a compression bandage .. overnight. v

Fig. 29.7 Elevation of orbital periosteum from floor with exposure of nasolacrimal duct. After Rob 6 Smith’s Operative SurgeryHead and Neck (1983). IA McGregor & D.r Howard (eds).

Postoperatiwe

Patients are advised not to blow their nose vigorously for 2 weeks in order to diminish surgical emphysema. Sutures should be removed after 4”days. Complications

Fig. 29.8 Area of orbit removed via Patterson’s approach in orbital decompression. After Rob 6 Smith’s Operative Surgery -Head and (eds). Neck (1983). IA McGregor & DJ Howard

5 All the bone of the medial wall can be removed as far asthe level of theethmoidal vessels andas far posteriorly as the hard sphenoidalbone surrounding the optic nerve. If furtherorbitalapex decompression is required, this should be done under endoscopic control with a drill designed for this purpose. 6 In orbital decompression, the orbital periosteum is incised in multiple horizontal and circumferential cuts. This can again be done under endoscopic control in the posterior orbit, using a curved disposable myringotomy knife or sickle knife. Angled scissors can also be used to join up the incisions and to break down the septaof the orbital fat. Gentle palpation of the globe will encourage extrusion of fat, but it should be remembered that the degree of decompression gained at the end of the procedure will not increase postoperatively. 7 In cases of trauma, the displaced bone may be mobilised andtrapped tissues disengaged. It is sometimes

These may be temporary or permanent. 1 Epiphora from oedema of orbicularis and nasolacrimal duct. 2 Paraesthesia in thedistribution of theinfraorbital nerve. 3 Diplopia from detachment of the inferior oblique and repositioning of the globe if a decompression has been performed. 4 Acute sinusitis if the maxillary or frontal sinus drainage is obstructed by the prolapsed orbital contents.

Osteoplastic indications

With the widespread use of alternative approaches, the indications for this approach have diminished considerably. Furthermore, the philosophy of obliteration of an infected sinus has been rejected by many surgeons. 1 Chronic suppuration which has failed to respond to all other means of treatment. 2 Removal of osteomata,althoughthecraniofacial approach is preferable for extensive lesions involving the skull base. 3 Repair of trauma to frontal bone. 4 Frontoethmoidal mucoceles: this approach is favoured in the USA.

External Operations on the ~rontoetbmoidalComplex

213

If the ethmoids, sphenoid or maxilla is extensively involved in the pathological process, it will be difficult to gain adequate access by this approach alone.

In addition toCT scans, which demonstrate the pathology, a plain occipitofrontal X-ray is required to provide a template of the frontal sinus. The template is cutfrom Silastic sheeting andcan be sterilised preoperatively. eratiue techni Preparation

1 The operation is performed under general anaesthesia. In the anaesthetic room the line of the incision is infiltrated with 1:200 000 adrenaline. 2 Prophylactic antibiotics are given with the premedication. 3 The patient lies in the reversed Trendelenburg position,withthe head placed so that theplane of the forehead is horizontal. Bilateral temporary tarsorraphies are performed. Incision

Either a bicoronal or a spectacle incision can be used (Fig. 29.9a7b).The bicoronal incision should not be used in men with a family history of baldness. It is made 2-3cm behind the hairline, in a strip which has been shaved. The incision is made through skin, subcutaneous tissue and frontalis muscle, taking care not to damage the periosteum, and extending inferolaterally to just anterior to the root of the helix. If a spectacle incision is used, the eyebrows must not be shaved. The incision is angled so that as few hair roots are transected as possible. Procedure 1 The flap is raised in the plane between the frontalis muscle and periosteum, as far as the supraorbital rims and glabella, if coming from above. Neurosurgical clips can be used on the skin edge to reduce bleeding. 2 Using the sterilised template, the frontal sinus is outlined superiorly and laterally, using a marking pen or methylene blue on a needle (Fig. 29.10). 3 Theperiosteum is incised aroundtheoutlineand

Fig. 29.9 (a) Position of bicoronal incision for osteoplastic flap operation. (b) Position of spectacle incision for osteoplastic flap operation in patient with male-pattern baldness. After Rob & Smith’s Operative Surgery-Head and Neck (1983). IA McGregor & DJHoward (eds).

elevated 2-3 mm either side. The bone is then cut with a fissure burr oroscillating (Stryker) drill(Fig. 29.1 1).The cut is made just within the outline and is bevelled to provide a supportive rim on closure. Care is taken to preserve the supraorbital and supratrochlear nerves. 4 The intersinus septum generally needs to be broken with an osteotome, allowing the flap to be prised down and forwards, hinged inferiorly. Furthercuts may be required inferiorly, particularly in males where the bone can be very thick. 5 Oncethe sinus cavities areexposed,the diseased mucosa or osteomacan be removed (Fig. 29.12). In chronic sinusitis, exponents of the operationrecommend

Fig. 29.10 Methylene dye used to outline frontal sinus template. After Rob eh Smith’s Operative Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

Fig. 29.12 Rosehead drill used to burr out contents of frontal sinuses. After Rob eh Smith’s Operative Surgery -Head and Neck (1983). IA McGregor & DJ Howard (eds).

complete exenteration of the mucosa and burring of the bone. 6 Two approaches are then possible, either drainage via the frontal sinus ostium, using one of a variety of techniques, e.g. a Silastic tube or rolled sheet, or an attempt to obliteratethe sinus. Thismay be done simply by inverting the mucosa of the frontal ostium or by formallyfilling the sinus with material such as fat. This should be taken from the anterior abdominal wall, but from theleft side to avoid subsequent confusion withan appendix scar. Bone chips have also been used. Closure

Fig. 29.11 Stryker drill used to perform osteotomies around margin of frontal sinuses. After Rob eh Smith’s Operative Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

The bone flap is repositioned and the periosteal layer carefully sutured with Vicryl. The skin is closed in two layers, of catgutand silk, of Prolene or with clips. Drainsareinsertedlaterallyand a pressure dressing applied for 24h.

Sutures or clips are removed at between 5 and 7 days.

External Operations on the ~rontoethmoidalComplex

1 Haematoma under the flap can be prevented by careful haemostasis, drains and a pressure dressing. Necrosis of the flap has been reported. 2 Infection of the primary (and donor)sites, with resultant osteomyelitis. 3 CSF leak following dural tears. This will require repair with fascia lata or nasal mucosa. 4 Cosmetic problems are not infrequent with this approach. The bicoronal scar may become obvious in men with a receding hairline. Rossing of the frontal bone or resorption of the bone flap can occur, requiring cranioplasty and bone grafting. 5 Recurrence of the original pathology. This has been reported to be as high as 25%.

This technique can be modified so that only one sinus is opened,cutting parallel withthe intersinus septum. It can also be extended into a lateral craniotomy for lesions arising in the superolateral orbit.

215

Goodale RL & Montgomery WVV (1958) Experiences with osteoplastic anterior wall approach to the frontal sinus: case histories and recommendations. Arch. Otolaryngol. 68, 271-83. Howarth WC (1923) A radical frontal sinus operation. J.Laryngol. Otol. 38, 341-3. Lang J (1989) Clinical Anatomy of theNose, Nasal Cavity and Paranasal Sinuses. Stuttgart, Georg Thieme Verlag. Lund VJ (1987) Anatomical considerations in the aetiology of frontoethmoidal mucocoeles. Rhinology 25, 83-8. Lund VJ & Rolfe M (1989) Ophthalmicconsiderations in frontoethmoidal mucocoeles. J.Laryngol. Otol. 103, 667-9. Lynch RC (1921) The technique of a radical frontal sinus operation which has given me the best results. Laryngoscope 31, 1-5. Macbeth RG (1954) The osteoplastic operation for chronic infection of the frontal sinus. J.Laryngol. Otol. 68, 465-77. Patterson N (l989) External operations on the frontal and ethmoidal sinuses. J.Laryngol. Otol. 54, 235-44. Rubin JS, Lund VJ & Salmon B (1986) Frontoethmoidectomy in the treatment of mucoceles: a neglected operation. Arch. Otolaryngol. 112,434-6.

N

The degloving approach affords excellent access to the middlethird of the face. It is, therefore, a versatile operation applicable to the following situations: 1 resection ofbenign sinonasal disease, inparticular inverted papilloma, angiofibroma, fibro-osseous disease and dermoid cysts; 2 septodermoplastyinthemanagement of hereditary haemorrhagic telangiectasia; 3 repair of large septal perforations; 4 repair of midfacial fractures; 5 midfacial bone grafting; 6 midfacial osteotomies; 7 resection of selected malignant tumours. It is possible to perform a bilateral maxillectomy via this approach and with appropriate dissection to explore the ethmoids, sphenoid, pterygopalatine and infratemporal fossae. The limits of resection are posteriorly the posterior wall of the sphenoid sinus, pterygoid muscles and plates, superiorly the roof of the ethmoids and Cribriform plate and laterally the coronoid process of the mandible.

There is no evidence from sequential studies that the midfacial approach adversely affects facial growthin children or adolescents provided the cartilaginous septum and palate are undistrubed. Thus there is no lower age limit and theprocedurehas beenused in children as young as 2 years old. Indeed, the operation is ideally suited to the young, enabling the avoidanceof a facial incision.

.

The precise extent of the problem is usually determined by preoperative imaging. Where appropriate, histology will be obtained, preferably under general anaesthesia. Coronal and axial CT scanning (with enhancement) and MRI (coronal, axial, sagittal) in TI and T2 spin echo sequences (with and withoutgadolinium-DTPA) may be required. In particular, coronal CT scanning is necessary to determine whether early cribriform plate erosion is present. Patients should be warned of the significant postoperative facial bruising and swelling, which may take several weeks to resolve.Similarly, temporary paraesthesia inthedistribution of theinfraorbital nerve is common, as is nasal crusting.

Lesions which extensively involve the frontal sinus, roof of theethmoids,cribriformplate or orbit cannot be reached by a midfacial degloving approachalone. In these circumstances a formal external approach, such as a lateral rhinotorny or craniofacial procedure, would be moreappropriate.However,the midfacial operation can be combined with a frontal craniotomy through a bicoronal flap and/or orbital clearance when indicated.

The position of the infraorbital foramen on the face of the maxilla and therelationship of thelowerlateral cartilages to the nasal septum are the key points in the initial dissection (Fig. 30.1).

216

Midfacial Degloving

2 .I '7

and caudal borders of the cartilaginous septum, separating it from the medial crura of the lower lateral cartilages. This incision is carried across thefloor of the nose to join the intercartilaginous incision laterally. It can be helpful to enter thenasal cavity through the oralincision or to cut down on atocurved clip placed from below to better define the pyriform aperture. Procedure in stages

Fig. 30.1 Area exposed by midfacial degloving, showing infraorbital foramen and pyriform aperture. After Rob & Smith's Operative Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

Operatiue technique Preparation

1 The operation is performed under general anaesthesia, with an endotracheal tube (ET) placed centrally in the mouth and a pharyngeal pack. Vasoconstriction of the soft tissues of the nose is facilitated by instillation of Moffett'ssolution(cocainesolution 4% and sodium toone-quarterpart bicarbonate 1% in equalparts 1:1000 adrenaline) in the anaesthetic room or placing ribbon gauze soaked in 1:1000 adrenaline intranasally, incision and injecting 1:200000 adrenalineintothe sites. 2 It is advisable to give abroad-spectrumantibiotic, either amoxycillin-clavulanate or cefuroxime axetil and metronidazole,withthepremedication and thereafter while any packing is in place. 3 The patient lies in a reversed Trendelenburg position with approximately 15" of head-up tilt. Bilateral temporary tarsorraphies should be performed.

1 The periosteum and soft tissues of the cheek are elevated as for a Caldwell-Luc operation, using a Farabeuf, Lempert or Freer elevator. This is continued superiorly to demonstratetheinfraorbital nerves and inferior orbital margins on both sides andthe bony margins of the pyriform aperture. It should also extend as farlaterally as possible to give the greatest mobility to the tissues for subsequent retraction (Fig. 30.3). 2 Through the intercartilaginous incisions, the soft tissues of the dorsum of the nose are elevated as far as the root of the nose and dissected laterally on to the maxillae to complete the mobilisation from below. Only if this dissection is completed superiorly and laterally will it be possible to completely deglove the rnidthird of the face (Figs 30.4 and 30.5). 3 Access is now possible to the nasal cavity and both maxillae. Further lateral dissection intotheinfratemporal fossa can be performed if the internal maxillary artery requires initial ligation. Alternatively the artery and its branches can be reached after removal of

Incision (Fig. 30.2)

A bilateral sublabial incision is made straight down to the bone, running from maxillary tuberosityto tuberosity. Routine rhinoplasty intercartilaginous incisions are continued into a transfixion incision along the dorsal

Fig. 30.2 Sublabial incision. After Rob & Smitb's Operative Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

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Chapter 30

Fig. 30.3 Elevation of soft tissues from face of maxillae, exposing infraorbital nerves. After Rob 6 Smith’s Operative Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

Fig. 30.5 Exposure obtained via midfacial approach. After Rob eP Smith’s Operative Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

the anterior and posterior walls of the maxilla, using either a drill or hammer, gouges andupcutting bone forceps. 4 Removal of the lateral wall of the nose, including the perpendicular plate of the palatine bone, allows excellent access to the nasopharynx, ethmoids and sphenoid. Firm retraction is required throughout the procedure and caremust be taken not to traumatisetheinfraorbital nerves. 5 Subsequent surgery will be determined by the surgical indication. Closure

Fig. 30.4 (a) Intercartilaginous and (b) transfixion incisions, to complete mobilisation of midfacial soft tissues. After Rob 6 Smith’s Operutive Surgery-Head and Neck (1983). IA McGregor & DJ Howard (eds).

Haemostasis should be achieved before closure which in many cases is facilitated by the insertion of a pack (or packs, either 1 inch (2.5cm) or2 inch (5cm) ) soaked in Whitehead’s varnish (compound iodoform paint -iodoform, benzoin, prepared storax, Tolu balsam and solvent ether). Precise closure is mandatory to avoid complications. Closure of the sublabialand vestibular incisions must be done with considerable care, using fine plain catgut, and thefrenulummust be correctly repositioned in the midline. Taping of the nose and the application of a plasterof-Paris nasal splint may be helpful in reducing facial oedema. In addition, IM an injection of 8-12mg of dexamethasone is often given peroperatively.

idf facial Degloving

Postoperative management The Whitehead’s varnish pack can be left in place for a few days to several weeks, depending upon the situation, and is usually removed under a short general anaesthetic (GA).Antibiotic cover is continued during this period. Following its removal, patients are advised to use saline sniffs three to four times per day until the nasal crusting settles.

Complications These can be temporary or permanent, although they are generally rare. 1 Vestibular stenosis, avoided by careful suturing. 2 Paraesthesia in thedistribution of theinfraorbital nerve. 3 Oroantral fistula, which usually occurs when previous surgery such as aCaldwell-Luc has been performed. 4 Epiphora. 5 Septal perforation if radicalseptodermoplasty performed bilaterally at the same time.

2 ,I

9

6 A subtle upward rotation of the nasal tip is often observed, rarely of any cosmetic significance. However, excess removal of the cartilaginous septum and frontal process of the maxilla should be avoided if possible, as it will result in nasal deformity.

Further reading Allen GW & Siege1 GJ (1981) The sublabial approach for extensive nasal and sinus resection. Laryngoscope 91, 1635-40. & Converse J M (1974)The midface Casson PR, BonnanoPC degloving procedure. Plastic Reconstruc. Surg. 53, 102-3. Howard DJ & Lund VJ (1992) Themidfacial degloving approach to sinonasal disease. J . Laryngol. Otol. 106, 1059-62. Maniglia AJ (1986) Indications and techniques of midfacial degloving. Arch. Otolaryngol. Head Neck Surg. 112, 750-2. Price JC (1986) The midfacial degloving approach tothe central skullbase. Ear Nose Throat]. 65, 174-80. Romo T, Foster CA, Korovin CS & Sachs ME (1988) Repair of the nasal septal perforation utillizing the midface degloving technique. Arch. Otolaryngol. Head Neck Surg. 144, 739-42. Sachs ME, Conley J, Rabuzzi D, Blaugrund S & Price J (1984) Degloving approach for the total excision of inverted papilloma. Laryngoscope 94, 1595-8.

al Rhinotomy and ial Maxillectomy NIGEL R. BLEACH

Preoperative management Thisprocedure is appropriatefortheexposureand resection of a wide variety of lesions affecting the nose and paranasal sinuses. These include inverted papilloma, juvenile angiofibroma, malignant melanoma andsinonasalcarcinomas(squamous,adenoid cystic, undifferentiated) (Sessions & Larson, 1977;Mertz et al., 1983). 1 Resection of anasal tumour involving thelateral nasal wall (ethmoid sinuses, middle and inferior turbinates, medial maxilla), such as inverted papilloma, limited ethmoidaltumoursandmucosalmalignant melanoma. 2 As amethod of access either to anteriorseptal lesions andtumoursor to posteriornasaltumours, e.g. juvenile angiofibroma and recurrent or persistent nasopharyngeal carcinoma. 3 To allow debulking of more extensive nasal malignancy, prior to palliative radiotherapyand/or chemotherapy.

1 Stage the disease, and confirm the extent of the lesion with CT scans (axial and coronal with contrast) and/or MRI. This will allow exclusion of patients with extensionsuperiorly via thecribriformplate, orintothe middle cranial fossa via the orbital apex or sphenoid, or posterolaterally into the infratemporal fossa or parapharyngeal space. 2 Confirm the histology of the lesion with biopsy under local anaesthetic (LA) with rigid Hopkin’s rod endoscopes or by formal examination under anaesthetic (EUA) and biopsy. 3 Exclude distant metastases (chest X-ray, CT scan of neck and/orthorax,ultrasoundscan of neck and/or abdomen,bonescan)as deemed appropriate in each case. 4 Obtain a baseline ophthalmic assessment of visual fields, acuity and proptosis.

Relevant anatomy (Fig. 31.1) The aim of the procedure is to resect en bloc the lateral wall of the nose, without damaging adjacent structures. The lateral wall of the nose comprises the ethmoid labyrinth and middle turbinate, the medial wall of the maxilla andtheseparateinferiorturbinate.Thelacrimal bone and nasolacrimal apparatus are in close proximity anteriorly, and the palatine bone, sphenopalatine foramen and sphenopalatine artery lie posteriorly. Important relations are as follows: l Medially: the nasal septum. 2 Laterally: the orbital periosteum with, superiorly, the fibroustrochlea,throughwhichthetendon of the superior oblique muscle passes. The trochlea sits in a

Lateral rhinotomy is not indicated: 1 If thetumour is too extensive to be adequately cleared by this method (e.g. intracranial spread, extensive orbital involvement or posterolateral spread intotheinfratemporalfossa).Under these circumstancescraniofacial resection or maxillectomy with infratemporal-fossa exploration may be required. 2 If aposterior tumour extends, or is sited, toofar laterally for adequate clearancevia this route,e.g. recurrent nasopharyngeal carcinoma. 220

Lateral Rhinotomy and ~ e d i a l ~ a x i l l e c t o m y221 lary (externals carotid), entersthe nose throughthe sphenopalatineforamen, which lies posterior to the middle turbinate on the lateral wall of the nose. The angular vein lies close to the medial canthus and runs down the lateral side of the nose, often causing troublesome and persistent bleeding during the procedure. The supratrochlear vessels pass superiorly to supplythe scalp from the medial superior orbital rirn. ,

The infraorbital nerve (maxillary division V)exits its foramen on theanterior surface of the maxilla, just below the midpoint of the inferior orbital rirn. It courses inferiorly, rapidly branching into the cheek to supply sensation to the overlying skin, including the upper lip, lateral nose and gingivae. Thesupratrochlear nerve (ophthalmic division V) passes superiorly, via the supratrochlear notch, to supply sensation to the forehead and anterior scalp.

Fig. 31.1 Anatomy.

shallow bony fossa in thesuperomedialorbital rim (frontal bone). Thelacrimal sac lies inferomedially, and sits posterior to the anterior lacrimal crest of the maxilla, on the anterior partof the medial orbital wall, with its duct passing inferiorly via the bony nasolacrimal canal to openintothe nose beneath the inferior turbinate. 3 Superiorly: the anterior skull base (cribriformplate and roof of ethmoid medially, frontal bone laterally) with the frontal sinus anterosuperiorly. 4 Inferiorly: the hard palatelfloor of nose, with the alveolus and superior dentition anteriorly. 5 Posteriorly: the nasopharynx and anterior sphenoid (sphenoid sinus and pterygoid process).

Theanterior and posteriorethmoidalarteries pass medially froln the ophthalmic artery (internal carotid) across the roof of the ethmoid and thence to the nose. They enter at the level of the frontoethmoidal suture, and actasalandmarkforthe level of theanterior cranial fossa floor and hence thedura.Theanterior ethmoidal artery lies approximately 2.5cm behind the anterior lacrimal crest, theposteriorafurther 1.2cm back. The sphenopalatine artery, a branchof the maxil-

The operation is performed under general ,anaesthetic (GA), withthepatient supine and the head elevated (reverse Trendelenburg position) to reduce venous pressure. Moderate hypotension is preferable (systolic pressure 80-100 mmHg). To further reduce intraoperative blood loss, the nasal mucosa is prepared with a topical vasoconstrictor, e.g. Moffett's solution (2m1 10% cocaine, 2 m1 1% bicarbonate, 1m1 1:1000 adrenaline), and the incision line is infiltrated withadrenaline 1:80 000. The skin is cleaned with aqueous chlorhexidine, and the head is drapedwith towels to exclude thehair, mouthand ear,but to adequately expose the nose, eye and cheek. The eye on the involved side is protected by a temporary tarsorrhaphy suture, using 5 l O silk or nylon. Broad-spectrum parenteral antibiotic prophylaxis is commenced on induction (e.g. cefuroxime 1.5 g), with three further postoperative doses.

The incision should be as illustrated in Fig. 31.2, with fine cross-hatches andlor tattooing with methylene blue to aid accurate wound closure. The incision starts midway between the medial canthus and the bony nasal dorsum, avoiding if possible theangular vein, and is taken inferiorly alongthe line of thejunction of the cheek with the nasal pyramid, to curve medially in

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Chapter 32

Fig. 31.2 Incision.

the nasal alar groove to enter the nostril. Superiorly, the classical incision should be extended to curve laterally beneath the medial eyebrow, staying on the bone and being careful to avoid falling inferiorly into the superior crease of the upper eyelid and hence into the orbit. The incision should go directly downto bone, through the periosteum, this incision lying medial to the attachment of the medial canthal ligament, which should therefore be preserved intact when the periosteum is subsequently elevated. Inferiorly, the incision goes through the nasal mucosa at the bony margin of the piriform aperture of the nose, allowing subsequent medial retraction of the nasal ala to expose the distal septum. The full length of the incision is deepened to bone by sharp dissection, which often causes bleeding from the angular vein; this is controlled using fine haemostats and 3/0 absorbable ties or with bipolar diathermy.The incision is. thenopened widely, using traction sutures andlor self-retaining retractors. Superiorly, an orbital retractor witha broad flat blade should be used, or alternatively malleable retractors, in order to avoid damaging the orbital fascia and to prevent pressure on the orbital contents. Toothed or rake retractors easily tearthe fascia, and inferiorly may damage the infraorbital nerve.

1 The periosteum is carefully elevated (Fig. 31.3),using a combination of sharp dissection with a 15 blade and Freer’s elevator, and blunt dissection, with small strips

of ribbon gauze. The periosteum is thus mobilised on a broad front, moving laterally until the orbital margin is reached, at which point the orbital periosteum strips easily from the medial orbital wall. It is tethered deeply by the conical strand of fascia surrounding the anterior ethmoidal artery, superiorly by the attachment of the trochlea and inferomedially by the lacrimal sac and its duct. 2 The trochlea can be carefully separated from its bony fossa by using sharp dissection with a 15 blade, which must be kept close to the bone and curved round the contour of the fossa (Cheesman, 198’7).Do not transect the fibrous trochlea by cutting straight acrossin the line of the orbital margin. Once the trochlea is released, the superomedialorbital rim andfrontoethmoidal region can be readily displayed. The trochlea shouldbe tagged, if possible, with a fine suture for lateridentification and repositioning. 3 Using the Freer’s dissector, the lacrimal sac can be gently mobilised from the bony fossa, just posterior to the anterior lacrimal crest. However, the duct itself disappears inferiorly within its bony canal. 4 To free the sac, the duct is mobilised within its bony canal, using small strips of ribbon gauze and a Freer’s dissector. The overlying bone is then removed, using a combination of acutting rosehead burr, fine bone nibblers and a downbiting Hajek’s punch forcep. This

Fig. 31.3 Elevating the periosteum.

Lateral ~ b i n o t o m yandMedialMaxillectomy

223

Fig. 31.4 Mobilising medial orbital structures.

allows theduct to be transectedapproximately 1cm below the sac. The proximal duct and the lacrimal sac are then carefully reflected superiorly, freeing the sac from its fossa and allowing wide mobilisation along the inferior orbital margin. 5 Furtherlateral elevation of periosteumacrossthe front of the maxilla allows identification of the infraorbital nerve emerging from its foramen near the orbital rim (Fig. 31.4).The nerve marks the lateral extentof the exposure. The dicided free edge of nasal mucosa at the piriformaperturecan be elevated fromthe overlying maxillary bone, again using a Freer’s dissector and then insinuating adrenaline-soaked ribbongauze between the mucosa and the bone. This reduces bleeding during subsequent osteotomy. 6 Before performing the osteotomies, the medial orbital periosteum must be elevated from the lamina papyracea and retracted laterally. This requires the division of the anterior, and sometimes the posterior, ethmoidal artery. Gentle dissection along the lamina papyracea, with lateral retraction of the orbital contents (using malleable retractors or a Ferris Smith or Luongo orbital retractor) will define the conical strand of fascia around the anterior ethmoidal artery, passing into its foramen at the level of the frontoethmoidal suture. The vessel may be secured withbipolardiathermy, or Ligaclips, before being divided. The posterior vessel liesin the same plane

about 1cm posteriorly, and may be treated similarly if posterior exposure is required, always remembering that the optic nerve lies only 5-6mm further posteriorly and is hence at risk. 7 Osteotomies are made as illustrated in Fig. 3 1.5, using a compressed-air drill and a fissure burr, or oscillating saw, with constant irrigation to prevent burning of bone. Because the nasolacrimal duct has been elevated from its canal and divided, the anterior osteotomy can pass lateral to this, opening into the maxillary antrum medial to the infraorbital nerve. Inferiorly the specimen is freed by using heavy curved Mayo scissors, which cut posteriorly, following the floor of the nose, just below the attachment of the inferior turbinate, low down on the lateral nasal wall. An oblique osteotomy from the inferior orbital rim, passes across the floor of the orbit, to meet the superior osteotomy running along the level of the ethmoidal roof.If these two cuts fail to meet, they are easily connected by making a small vertical fracture through the lamina papyracea with a Howarth’s elevator. Anteriorly, the superior osteotomy may be curved upwards to open the frontal sinus, if this is thought necessary. 8 The whole bony specimen can be fractured medially, inferiorly and anteriorly to deliver a block of tissue, comprising maxillary bone anteriorly and withthe ethmoidallabyrinth and lateral wall of noselinferior

224

Chapter 32 a drill hole in the adjacent bone (Sessions & Humphreys, 1983), but careful closure of the periosteal layer should ensure adequate medial supportforthe eyelids (Mertz et al., 1983). 3 After removing thetarsorrhaphysuture,thetwo lacrimal puncta can be cannulated and stented, using a Silastic O’Donohoe stent, passing the probes into the lacrimal sac and down into the divided duct. The two fine Silastic stents are tied in a knot in the nasal cavity, leaving a fine Silastic loop at the medial canthus, which keeps the lacrimal apparatus patent. 4 The remaining anterior nasal cavity is packed with more Whitehead’s varnish ribbon gauze, and the skin incision is closed with fine nylon (510 or 6/0) sutures, using mattress sutures if necessary and making sure that apposition is accurate, using the previous cross-hatches. 5 An eye-pad dressing is placed, afterprotectingthe cornea with chloramphenicol eye ointment.

Fig. 31.5 Osteotomies and bony resection with orbit retracted laterally.

1 The patient is kept on bedrest for 24 h with the head elevated to reduce facial swelling. If thepatient is pyrexial or the nasal pack appears infected, oral antibi-

has otics prophylaxis parenteral may be after continued ceased, until the nasal pack

turbinateattached. If the specimen remainstethered posteriorly, it may be freed with heavy-scissor dissection, although this may produce brisk bleeding from the sphenopalatine artery. 9 Haemostasis is obtained, using hot, moist, gauze packs and diathermy as necessary. Any suspicious margins or residual posterior ethmoidal air cells are cleared under direct vision, with frozen-section histology if required, and occasionally further dissection using the operating microscope may be necessary. The cavity may then be packed with 2.5cmribbon gauze soaked in Whitehead’s varnish (compoundiodoforminether), which is antiseptic and dries to form a firm haemostatic pack.

closure (Fig. 31.6) l Traction sutures and retractors are removed, and the trochlea is resited in its fossa and sutured with 310 nylon or Prolene to the adjacent periosteum of the frontal bone. 2 A deep layer of absorbable (310 Vicryl) sutures closes the periosteum and subcutaneous tissues. If necessary, the medial canthal ligament should be formally resutured to theperiosteum(Bernard et al., 1989) or to

Fig. 31.6 Closure.

is removed (7-10 days).

Lateral Rhinotomy and Medial ~axillectomy Antibiotic eye ointment or drops are prescribed for 2-5 days as necessary. 2 Initial diet is usually fluid, butcan be rapidly increased through soft diet to full diet as tolerated by the patient. Mobilisation can begin after 24h. 3 The nasal pack is removed at 7-10 days. This may requireaformal GA, asthe large, firm pack is often difficult and painful to remove through the nostril once the incision has been closed. At the same time, a careful EUA with decrusting and cleaning of the cavity is possible. Sutures are removed after pack removal. 4 Eye function is reassessed, and radiotherapy is planned if necessary prior to discharge. 5 Thenasolacrimalstentsare removed after 8-12 weeks as anout-patientprocedure, by dividing the Silastic loop at the inner canthus and withdrawing the stents through the nose.

225

3 A late frontonasal mucocele may occur, due to dam-

agefrontonasal toduct, the and obstructed.

which becomes stenosed

Neurological

1 CSF rhinorrhoea; meningitis. 2 Facial or dental paraesthesia due to infraorbital-nerve damage or superior alveolar-nerve damage. Cosmetic

Cosmetic results are usually good,butcomplications can present late in upto 10%of patients (Bernard et al., 1989). These include nasal collapse related to loss of lateral nasal support, medial canthal webbing and an unacceptable scar (usually due to a misplaced incision.)

Complications

Alternative procedures

Complications may be immediate (0-2%)or delayed (15-20%) (Mertz et al., 1983; Bernard et al., 1989).

Lateral rhinotomy strictly refers to the external incision only, and the procedure described in this chapter (medial maxillectomy) represents a maximal resection for largertumoursorfor wide access. More limited or anterior lesions can be approached via a smaller incision and a moreconservative bony resection. However, if the nasolacrimal sac andlor trochlea are notmobilised, then the exposure provided may become quite limited. Some smaller lesions, e.g. a limited area of recurrent inverted papilloma, can be managed using an endoscopic technique with careful follow-up.

Optic

1 Transient eyelid oedema is common during the first few days. 2 Optic-nerve damage and blindness. 3 Diplopia aftertrochleartrauma or displacementusually transient. 4 Epiphoraandlor dacrocystitis dueto nasolacrimalduct stenosis. Nasal

1 Epistaxis -primary or secondary haemorrhage; haematoma. 2 Crusting-lateral rhinotomy with medial maxillectomy produces an enlarged sinonasal cavity which crusts readily. Itcan be managedwith glucose and glycerine nose drops (to soften thecrusts and reduce bacterial contamination),withsteaminhalationsand saline douches (to soften and clear established crusting) and by formal decrusting by the surgeon as required. Crusting usually resolves after 6 months, but is worse in irradiated patients (Bernard et al., 1989).

References Bernard PJ,Lawson W, Biller HF & LeBenger J (1989) Complications following rhinotomy -review of 348 patients. Ann. Otol. Rhinol. Luryngol. 98, 684-92. Cheesrnan AD (1987) Lateral rhinotomy. In: Chapter 18 -Nonhealing granulomata andtumours of the nose and sinuses. In: Mackay IS & Bull TR (eds)Scott-Brown’s Otolaryngology, Vol. 4, Rhinology, 5th edn. London, Butterworths, p. 308. Mertz JS, Pearson BW & Kern EB (1983) Lateral rhinotomy -indications, technique and review of 226 patients. Arch.Otolaryngol. 109,235-9. Sessions RB & Humphreys DH (1983)Technical modifications of the medial maxillectomy. Arch. Otolaryngol. 109, 575-7. Sessions RB & Larson DL (1977) En bloc ethmoidectomy and medial maxillectomy. Arch. Otolaryngol. 103, 195-202.

Maxillectomy and Maxillary Swing WILLIAM I. WE1

indications

therapy. The tumour is located in the nasopharynx or affects the lymph nodes in the paranasopharyngeal area. (b) Adenoid cystic carcinoma arising from minor salivary glands in the nasopharynx. (c) Chordoma extending into the nasopharynx. 2 Exposure of the infratemporal fossa for removal of benign localised pathologies. These include neurogenic tumours arising from nerves located at the base of the skull and deep-lobe parotid tumours located medial to the mandible.

Maxillectomy

l Extirpation of malignancies arising from or affecting the maxillary sinus. (a) When the primary tumour is located in the hard palate or affects only the inferomedial wall of the sinus, or whenatumour of theupperpart of the buccal mucosa involves the maxilla, thenmaxillectomy with preservation of the orbital floor is indicated. (b) When the tumouraffects the roof of the sinus, but is not invading the orbit, then the floor of the orbit should be included in the resection but the periorbita should be left behind to support the orbital contents. (c) Whenthetumourextendsintotheorbit and affects intraorbitalcontents,thenorbitalexenteration should be carried out, together with the maxillectomy. (d) Extensive tumours involving theethmoidlabyrinthandthecribriformplateshould be removed with the craniofacial resection combined with maxillectomy. 2 Extensive benign pathologies affecting the maxilla, such as ameloblastoma, neurogenic tumours and osteoradionecrosis of the maxilla after radiotherapy. These lesions are fortunately rare.

Contraindications Maxillectomy

When the tumour is so extensive that bilateral maxillectomy would be required for clearance. Maxillary swing

1 In a patient with severe trismus. Under this circumstance, it is not possible to introducethe curved osteotome intraorally to separate the pterygoid plates from the maxillary tuberosity. 2 In young patients, as the development of the maxilla may be affected.

Preoperative management

Maxillary swing

The patient should undergo adequateclinical and radiological assessment. The mobility and visual acuity of the eyes should be tested and anydistant metastasis excluded. Endoscopic examination of thenasopharynx and related area is usually carried out and CT scans in

1 Exposure of thenasopharynx and theparanasopharyngeal region for oncological extirpation of tumours in the region. (a) Recurrent nasopharyngeal carcinoma after radio226

~ a ~ i l l e c t o mand y axillary Swing

227

both axial and direct coronal planes, performed with contrast, is mandatory in order to define the extent of the pathology. A biopsy is carried out to determine the exact nature of the lesion, as and when indicated. Before the operation, the patient should be seen by a prostheticorthodontist so thatan impression of the upper alveolus can be taken and a dental platemade. At operation, this plate will be used to hold the temporary prosthesis after maxillectomy and to fix the maxilla to the opposite hard palate to facilitate healing after the maxillary-swing procedure. Theskin over thethigh is preparedasadonor site for split-thickness skin graft.This is used after maxillectomy to cover the raw area on the inner aspect of the cheek flap to prevent contracture. In some patientstheextent of resection cannot be determined before operation and orbital exenteration may be necessary at the time of operation. The possibility of removing the eye should therefore be discussed with the patient before operation.

Antibiotics

Relevant anatomy

For maxillectomy, the Weber-Fergusson incision is used. This starts about 1cm lateral to the outer canthus of the eye and extends medially at 3mm below the eyelash. If the incision is placed too close to the eyelash, ectropion may develop. If placed too low, oedema may occur in the area above theincision. When reaching the medial canthus, the incision is curved inferiorly along the side of the nose until it reaches the alar groove. It is then continued medially to the midline, where it turns downwards ata right angle and divides the upper lip up to the vermilion. For the maxillary-swing procedure, the incision starts about 2cm lateral to the outer canthus of the eye. Its starting-point is placed more inferiorly to give adequate exposure of the zygomatic arch. The curve of the incision at the medial canthus region is made as obtuse as possible to allow ample blood perfusion. This prevents wound dehiscence in this area, especially for those patients who have had radiotherapy (Fig. 32.1). The incision over the vermilion portion of the upper lip is angled to prevent subsequent scar contracture and upward retraction of the lip. For maxillectomy the lipsplitting incision is then extended in two directions. The first incision passes between thecentral incisors and continues over the hard palate until it reaches the junction between the hard and soft palates. It then turns laterally towards the posterior aspect of the tuberosity of the maxilla. The other incision turns laterally in front of the incisor and extendsalongthe gingivobuccal sulcus to meet the first incision behind the maxillary tuberosity (Fig. 32.2a). The palatal mucosal incision is

The maxilla is shapedasaquadrilateralpyramid occupied by the maxillary sinus. Its roof is the floor of theorbitand its medial wall withtheturbinates formsthelateral wall of the nose. It is attached to the facial skeleton through four bony processes. Laterally the zygomatic process is attached to the zygomatic arch. Superomedially the maxilla is attached to thefrontal bone throughthefrontal process and medially it is attached to theopposite maxilla with the palatine bone, which forms the hard palate. Posteriorly, the maxillary tuberosity is attached to the pterygoid plates. Theblood supply of the maxilla is derived from the perforating branches of the facial, maxillary, infraorbital and palatine vessels through the soft tissue attachment over the bone.

Operative technique Preparation

Anaesthesia

Both maxillectomy and maxillary-swing operations are performed under general anaesthesia. An endotracheal tube (ET) is inserted through the nose opposite to the side of the maxillectomy. For maxillary-swing resection, preoperative temporary tracheostomy for ventilation is performed. The nasal and oral cavities are left free for various operative manoeuvres.

As the surgical field involves the oral cavity, systemic broad-spectrumantibioticsarestarted preoperatively and the Bacteroides species should be adequately covered. Position

The patient is placed in a supine position with the head slightly elevated. A pharyngeal pack is inserted. A temporarytarsorrhaphysuture is placed onthe affected eyelid and the othereye is covered with protective tape. The operative site is cleaned from the forehead down to the root of the neck and draped. Preparation of the neck is also necessary in case carotid artery control is needed during surgery. The oralcavity is cleaned with antiseptic solution. Incision

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Chapter 32

Fig. 32.1 Facial incision for maxillectomy. When used for maxillary swing, the lateral end of the incision should be extended more laterally and inferiorly.

placed onthe side of the resection, 3mm lateral to the midline. This develops amucoperiosteal flap to be used to cover the raw bony edge of the remaining palate. In maxillary-swing procedures, only the incision over the palate is employed and, as themaxilla is returned at the endof the operation, this palatal incision is placed in the midline. There is no need for another incision in the gingivobuccal sulcus (Fig. 32.2b).

Fig. 32.2 (a) Intra-oral incision for total maxillectomy. (b) Intra-oral incision for the maxillectomy swing procedure.

Procedure in stages

Dissection of soft tissue For maxillectomy, the entire cheek flap is lifted off the anterior bony wall of the maxilla extending from the zygomatic arch to the pyriform sinus. The orbicularis oculi is left intact and the periosteum is incised over the orbital rim and elevated to allow access to the orbital floor. If the tumour involves the anterior bony wall of the antrum, then muscle and soft tissue should be left attached to the maxilla. The infraorbital nerve and vessels are divided when encountered at the infraorbital foramen (Fig. 32.3). The incision over the hard palate divides the mucosa and, when turned laterally, it separates the soft palate from the hard palate. In maxillary swing, it is mandatoryto leave the greater portion of the cheek flap attached to the anterior wall of the maxilla. Dissection elevates only those soft tissues that allow exposure of the zygomatic arch, 5mm

width of the anterior bony wall of the maxilla and the incisive fossa withthe bony wall below theanterior nasal spine. Division of the infraorbital nerves and vessels and separation of thesoftpalatefromthehard palate are similar to those for maxillectomy (Fig. 32.4). The angle of turn of the palatal incision is again made as obtuse as possible to retain maximum blood supply (see Fig. 32.2b).

Osteotomy For maxillectomy, the zygomatic arch is divided with an oscillating saw, continuingmedially to the lateralpart of the infraorbital fissure. The osteotomy extends across the anterior part of the floor of the orbit to include the infraorbital rim until it joins the pyriform aperture.The medial wall of the maxilla is transected with a straight

Maxillectomyand ~ a x i l l a Swing ~y

223

Fig. 32.3 The extent of elevation of soft tissue off the anterior wall of the maxilla for total maxillectomy.

Fig. 32.4 The extent of soft tissue elevation when carrying out a maxillary swing procedure with the osteotomy site marked.

osteotome at the level of the middle turbinate. The hard palate is also divided with an oscillating saw, going from anterior to posterior, or alternatively with a Gigli saw that has been passed through the nose and brought out at the junction of the soft and hard palates. The mobilisation of the maxilla is completed by inserting a curved osteotome between the tuberosity of the maxilla and the pterygoid plates (Fig. 32.5). In maxillary-swing procedures, before makingthe osteotomies, holes are drilled for the rniniplates which will be used to stabilise the maxilla after it is returned. The plates are positioned over the zygomatic arch and over the bony area under the nasal spine. Two separate holes are drilled over thesuperomedial aspect of the anterior wall of the maxilla and theadjacentfrontal process for insertion of wire. This will further stabilise the repositioned maxilla. The osteotomies for a maxillary-swing procedure are similar to that for a maxillectomy with two exceptions. The zygomatic arch is not completely divided; the osteotomy starts from the lower border of the arch and extends medially into the osteotomy over the anterior wall of the maxilla. Theanterior-wallosteotomy is placed below and parallel to the orbital rim; the orbital floor is not divided (Fig. 32.6).

Mobilisation of maxilla For total maxillectomy, after making the appropriate osteotomies, the bony maxilla can be removed and any attached soft tissue is divided with scissors. The maxillary artery may be encountered when the posterior wall is mobilised and canthen be ligated. Haemostasis canbe achieved with stitches, especially over the pterygoid muscle area. In maxillary swing, aftercompletion of the osteotomies, the bony maxilla drops from its usual position, while still attached to the anterior cheek flap. The maxilla can be swung laterally to expose the nasopharynx and the paranasopharyngeal area so that the appropriate procedure can be carried out as indicated (Fig. 32.7). Closure/drainage/dressings

On completion of a totalmaxillectomy, a split-thickness skin graft is employed to cover all the raw areas, especially over the inner aspect of the cheek flap to prevent contracture. This graft is secured in position with quilting stitches. A temporary prosthesis is inserted and used to reconstructthe facial contour. A dentalplate pre-

230

Chapter 32

Fig. 32.5 The osteotomy required for maxillectomy. The curved osteotome is placed behind the maxillary tuberosity to separate it from the pterygoid plates.

Fig. 32.6 The site of Osteotomy for maxillary swing procedure. Tht holes for holding the plates were drilled before the Osteotomy.

pared preoperatively is inserted to be attached to the existing dentition on theopposite side. This fills the palatal defect and holdsthetemporary prosthesis in position. The cheek flap is returned and the wound is closed in layers (Fig. 32.8). For maxillary swing, on completion of resection of the lesion in thenasopharynxandtheparanasopharyngeal region, haemostasis should be secured with stitches and cautery. The inferior turbinate is removed and its overlying mucosa dissected and used as a free graft to cover the raw area created after the resection. This mucosal graft facilitates healing and reduces exposure of any surroundingbony components. The laterally swung maxilla is returned to its originalposition. Miniplates are placed over the zygomatic arch area and the bony part below the nasal spine. The plates are fixed with screws inserted into the holes prepared before the osteotomy.Wire is inserted through the holes in the superomedialportion of the maxilla and thefrontal process to provide further stability (Fig. 32.9). The incision over the soft palate is closed in layers with interrupted sutures and the mucoperiosteum over the hard palate is sutured in one layer. The dental plate constructed before the operation is

inserted. This will immobilise the repositioned maxilla by fixing it to theoppositedentitionwith wire. A nasal pack consisting of ribbon gauze soakedwith Whitehead’s varnish is employed onthe side of the swing and a Foley’s catheter is inserted throughthe other nostril. The balloon of the catheter is distended with 7m1 of water and placed in the nasopharynx. This helps to hold the free mucosal graft and keeps the nasal pack in position. The facial wound is closed in layers, using absorbablesuturesforsubcutaneous tissue and 610 nylon for skin.

Postoperativ Patients who have hada maxillectomy or maxillary swing can commence oral intake in the form of fluids on the second day. The facial sutures are removed on the seventh postoperative day. However,if the patientshave had previous irradiation, the removal of stitches is delayed until the second week after the operation. After maxillectomy the resulting cavity is douched frequently with warm water to remove crusts or debris. When the wound has completely healed the temporary prosthesis is changed to a permanent one.

~ a ~ i l l ~ and G ~ ~o a~~ yi l l Swing a~y

23 I

Fig. 32.7 During the maxillary swing procedure, after completion of

Fig. 32.8 The maxillary defect after resection is filled up with a

the osteotomies, the bony maxilla which is attached to the anterior cheek flap can be swung laterally to expose the nasopharynx.

prosthesis.

For maxillary-swing patients, the Foley’s catheter and nasal pack are removed about 1 week after the operation, The nasalcavity is also douched with warm saline to remove any debris. The dental plate is removed only at 6 weeks after the operation.

3 Facial depression on the side of operation may develop. Thiscan be improved withtheinsertion of a larger prosthesis. 4 Movement of the eye may be affected if the suspensory ligaments are divided and too much of the floor of the orbit has been removed.

1 Bleeding in the early postoperative period may come from the internalmaxillary artery or from vessels on the raw area.However, this is prevented by meticulous haemostasis at the time of the operation andby inserting the nasal pack and the temporary prosthesis. 2 Cosmetic problems such as ectropion may develop if the incision is placed too close to the lid. Should this occur, the scar ought to be excised and a full-thickness skingraft inserted between theseparated skin edges. When theincision is placed too farbelow the lid margin, oedema of the strip of skin may develop. This is difficult to manage and, in extremecases, the whole lower eyelid may have to be excised and replaced with a full-thickness skin graft.

1 Bleeding and facial scar problems are similar to those of maxillectomy. 2 Dissection or resection of the pterygoid muscles causes all patients to develop a certaindegree of trismus. This usually improves with conservative management. 3 The palatal wound may fail to heal, resulting in a palatal fistula which interferes with swallowing and speech. However, the fistula may gradually contract to a very small size, thereby greatly improvingfunctional sequelae. Larger fistulae can be closed with a rotation palatal flap. Patientswith severe trismuscanweara dental plate.

Fig. 32.10 Facial incision when orbital exenteration is combined

with maxillectomy.

Fig. 32.9 The maxilla is returned to its original position and fixed to the rest of the nasal skeleton with screws, plates and wires.

Alternative p r ~ ~ e ~ u r e s Orbital clearance

When the maxillary tumour infiltrates the floor of the orbit and affects the orbital contents, the eye has to be removed to achieve complete clearance. The facial incisions are similar to thosefor maxillectomy withthe addition of an incision at the edge of the upper eyelid removing the tarsal plate (Fig. 32.10). The skin o f the upper eyelid is not removed unless it is infiltrated by tumour,which is uncommon. The eyelid skin is retracted with stay sutures and the globe is mobilised with blunt dissection, starting from the anterosuperioraspect and proceeding posteriorly and inferiorly. The orbital

periosteum is elevated from the roof of the orbit and freed around the whole orbit to the apex, where the optic nerve and the ophthalmic artery aredividkd. Sirnilarly, both the lateral and medial suspensory ligaments are divided. The oscillating saw is used to divide the floor of the orbit to achieve the tumour clearance margin. After haemostasis, the skin o f the eyelids is sutured and placed back into thesocket of the orbit with a pack. When removing the pack after 2 weeks, the bony socket will be lined by the skin and a prosthetic eye can then be constructed.

Further rea Ketcham AS & Van Buren JM (1985) Tumors of the paranasal si] Surg. 150, 406-13. nuses: a therapeutic challenge. Am.. Terz JJ, Young HF & Lawrence W Jr (1980) Combined craniofacial resection for locally advanced carcinoma of the head and neck. I1 Carcinoma of the paranasal sinuses. Am. J .Surg. 140, 618-24. Wei W , Lam KW & ShamJST (1991)Newapproachtothe Head Neck 13,200-7. nasopharynx: the maxillary swing approach.

T J.S. BRICGS riginal illustrations by John Li

Anterior craniofacialresection (CFR) is an operation for radical resection of tumours involving the ethmoid complex. The entireethmoid is removed,includingthe cribriform plateand attached dura. Orbital exenteration and maxillectomy may be included as necessary. CFR is usually performed for malignant tumours of the paranasal sinuses and is generally combined with pre-or postoperative radiation therapy. Itis essential that effective repair of the anterior cranial-fossa defect is achieved, if complicationsare to be avoided. Several surgical approaches to resection and repair have been developed. Thetwo mostcommonly utilised are described: thedirecttransfacialapproachwithnonvascularised repair (Cheeseman et al., 1986), and the combinedbicoronal,transfacial approach utilising a vascularised pericranial flap repair (Price et al., 1988; Sundaresan & Shah, 1988).

In the following circumstances, CFR of malignant neoplasms is unlikely to achieve clear margins or significant disease control. 1 Extensive frontal-lobe invasion by tumour is demonstrated. 2 Malignant melanoma orbulky undifferentiated carcinomas (e.g. sinonasal undifferentiated carcinoma) (Levine et al., 1987). 3 Tumour involves the posterior wall of sphenoid, cavernous sinus, internalcarotidartery(ICA) or optic chiasma. 4 Bilateral orbital invasion. 5 Distant metastases.

n~ication 1 Resection of malignantparanasalsinustumours involving the ethmoid or frontal sinus with proximity to or involvement of the cribriform plate, e.g. olfactory (aesthesio-) neuroblastomas, carcinomas and chondrosarcomas. 2 Resection of benign tumours of the paranasal sinuses, meninges or skull base with either extension through the skull base or cribriform-plate involvement, for example olfactory-groove meningiomas, inverted papillomas and fibro-osseous lesions. 3 Resection of malignantorbitaltumourssuch as lacrimal-gland carcinomas. "3 3

reoperatiwe mana~ement 1 Accurate staging of local tumour extent, using both CT and MRI toassess resectability and plan margins of resection. (a) CT-accurately identifies bonedestruction and cribriform-plate invasion. (b)MRI: (i)furtherdemonstratesintracranialextension and dural penetration; (ii) differentiates tumour from mucus or mucosal swelling withinobstructed sinuses, particularly the frontal and sphenoid. 2 Biopsy and direct examination of tumour extension with rigid endoscopes under local anaesthetic (LA) or formal examination under anaesthetic (EUA). Definitive histopathology is required, including immunohistochemistry-particularlyforapparentlyanaplastic lesions -to exclude lymphoma or malignant melanoma.

234

Chapter 33

3 Exclude regional or distant metastatic disease, including CT of thorax and upper abdomen, bone scan, etc. 4 Multidisciplinary team assessment and planning of combined-modality therapy. (a) Preoperative radiationtherapy-requiresrepeat imaging prior to surgical resection 6 weeks following therapy. (b) Postoperative radiationtherapy-requires that a vascularised reconstruction of the anterior cranialfossa floor is utilised. A non-vascularised repair will not be viable enough to withstand radiotherapy until 3 months postsurgery (Cheeseman et aE., 1986). 5 Obtain baseline ophthalmic assessment of visual fields, acuity and proptosis. 6 If maxillectomy is necessary, adental obturator should be prepared for fitting at the time of resection. 7 The patient should be fully informed of the expected outcome, risks and possible complications. Permission for orbital exenteration should be obtained if tumour appears to involve the orbit. 8 Preparation of autologous fibrin glue for use in the dural repair.

Fig. 33.1 (a) Saggital anatomy. (b)Saggital anatomy showing extent of resection.

usua I

CFR generally involves en bloc resection of the ethmoid, including cribriform plates, crista galli, fovea ethmoidalis, lamina papyracea on the side of and tumour, posterior wall of frontal sinus, dural sheaths and olfactory nerves, nasal septum and lateral nasal wall. Depending upon tumour extension, resection may be extended to include maxillectomy andlor orbital exenteration. The externalnasal bones, facial skin, anterior wall of frontal sinus or frontal bone, orbital roof, anterior fossa dura,olfactory bulbs and even frontal lobe can all be included in the resection if involved by tumour. The important anatomical relations are those of the cribriform plates and the ethmoid labyrinth. These can be considered in the axial, coronal and sagittal planes (Figs 33.1-33.3). The cribriform plates of the ethmoid lie at approximately pupillary level. Thefrontal sinuses, situated anterosuperiorly within the frontal bone, are connected to the ethmoid by the frontonasal recesses (ducts). The

Anterior CraniofacialResection

23 5

Fig. 33.2 Anterior fossa, t:thmoid and orbit from above.

Fig. 33.3 Coronal anatomy showing usual extent of resection.

crista galli, to which dura is very adherent, rises superiorly between the anterior cribriform plates. The cribriform lies recessed between the superior cells of the ethmoid labyrinth and its roof, the fovea ethmoidalis of the frontal bone. Posteriorly, the cribriform is bordered by the jugum of the sphenoid bone (planum sphenoidale) (Fig. 33.2). The olfactory bulbs and tracts lie within the cribriform recess on the inferior surface of each frontal lobe.

Theolfactory nerves, each withaduralsheath, penetrate the cribriform plates to supply the nasal mucosa. Each ethmoid labyrinth is bordered laterally by the orbit and posteriorly by the sphenoid sinus. Of great importance is the relationship of the optic nerves to the posterior ethmoidcells and sphenoid sinus. The orbital apex is lateral to the posterior ethmoid air cells. In some cases, however, pneumatisation extends into the sphenoid bone and ethmoid air cells may lie

236

Chapter 33

lateral to theoptic nerve. Similarly, theoptic nerves often indent the lateralwall of the sphenoid sinus and in some cases are dehiscent within the sinus. The nerves run from lateralto medial as they exit the orbits through the optic canals, crossing medial to the ICAs to form the intradural optic chiasma. For the anatomy of the lateral nasal wall and medial orbit, refer to the chapter on Lateral Rhinotomy and Medial Maxillectomy (Chapter 31). Thepericranium of thefrontal bone receives a rich vascular supply from the supraorbital and supratrochlear vessels. The vessels initially run superficial to thepericranium.Thereforethepericranium should not be separated from the overlying galea all the way to the orbital rim if blood supply is to be preserved. Laterally the pericranium fuses with the temporalis fascia enveloping thetemporalis muscle. Thefrontal branch of the facial nerve crosses the midzygomatic point to run onthe undersurface of the temporoparietal fascia, superficial to the temporalis fascia.

The operation is performed under general endotracheal anaesthesia in the supine position. The head of the table may be elevated (reverse Trendelenburgposition) to reduce venous pressure, except during the craniotomy, as air embolism may occur. Phenytoin administration is commenced preoperatively and continued until recovery is complete. Broadspectrumantibioticprophylaxis (e.g. cefotaxime) is commenced at inductionandcontinuedfor at least 48 h. Dexamethasone (1Omg) is administered to reduce anyfrontal-lobe oedema secondary to the surgical manipulation. Urinary catheter and arterial and central venous access lines are placed to facilitate monitoring.Nasal mucosal vasoconstriction is achieved by topical application of Moffett’s solution (10% cocaine, 1:1000 adrenaline, 0.9% bicarbonate). The incision line is infilfrated with 1% xylocaine and adrenaline 1:80 000. If a bicoronal incision is to be used, the anterior scalp is shaved. After skin preparationwith Betadine solution,the head is draped to exclude theendotrachealtube and earandto expose the midface, eyes, forehead and scalp as necessary. Bilateral temporarytarsorraphy sutures are placed after corneal lubrication with chloromycetin ointment. The thigh is shaved and prepared circumferentially for harvesting of fascia lata and split-skin graft. For lesions where extensive frontal-lobe elevation or

retraction is anticipated, a lumbar spinal-drainage catheter is placed to allow CSF removal at the time of craniotomy. Brain shrinkage is achieved by controlled hyperventilation to maintain a low partial pressure of arterial carbon dioxide (Paco,). Intravenous mannitol and frusemide are administrated 30min prior to craniotomy.

Procedure: tra Incision

For the direct transfacial procedure, an extended lateral rhinotomy incision is made on the side of maximal involvement by tumour. The incision is carried through to the bone, and superior to the medial canthus it should curve toward the midline and across the central forehead to the hairline. Preferably a suitable vertical skin crease (frown line) is followed across the glabellar region (Fig. 33.4). Facial flaps are mobilised by subperiosteal elevation to expose the nasal bones, frontal processes of the maxilla andfrontal bone, at least asfarlateralasthe supraorbital vessels. A self-retaining retractor is placed superiorly. The upper lateral cartilageis separated from the nasal bone to allow complete retraction of the nasal ala by tractionsutures.Haemostasis is secured with diathermy. Absorbableties to the angularvessels may be necessary. If there is any doubt about the degree of intracranial extension and resectability, the craniotomy can be performed first and the cribriform plate explored. Usually,

Fig. 33.4 Extended lateral rhinotomy incision.

AnteriorCraniofacialResection however, the inferior dissection and mobilisation of the specimen are done first. This facilitates the subsequent superior bone cuts, as they can be safely made through the orbital roof while the periorbita is protected. Also the duration of the open craniotomy and the amount of frontal-lobe manipulation are minimised. loration of medial orbital wall

As described for medial maxillectomy, periosteum is elevated to expose the lacrimal fossa and medial orbital wall. Posterior to the medial canthal ligament, the orbital periosteum (periorbita) should be easily elevated from the lamina papyracea. The trochlea is separated from its attachmentand theanteriorandposterior ethmoid arteries are divided after bipolar coagulation. The lacrimal sac is mobilised andtheduct divided inferiorly, after removal of the anterior wall of its canal. This allows lateral retraction of orbital contents, using malleable retractors, and access to the medial orbital wall, floor and roof (Fig. 33.5). If the lamina papyracea is eroded by tumour, careful examinationshould be madefor involvement of the periorbita (preferably using the operating microscope). Involved periorbitashould be resected. This may be done after themain specimen is removed to allow better access. Prolapse of orbital fat is controlled by a quilted absorbablesuture and a split-skin graft or by fascia patch repair.

Fig. 33.5 Lateral orbital retraction and frontal craniotomy.

237

Invasion of tumour through the periorbita into the orbital contents requires orbital exenteration. If tumour involves the contralateral ethmoid, the medial orbital wall should be explored on that side and the periorbita mobilised to allow complete ethmoid resection, including the lamina papyracea. r osteotomies Inferiorly, theextent of bone removal and site of osteotomies will depend on theproximity of thetumour. Usually the anterior buttress and frontal process of the maxilla is mobilised by osteotomies, as shown (Fig. 33.6),facilitating en bloc removal of the ethmoid specimen. For small tumours that do not involve the anterior maxillary sinus, a more conservative bone removal can be utilised. Piecemeal removal of the specimen is then likely to be required. Osteotomies are most easily made using a high-speed drill and fissure burr. Mobilisation of the lateral nasal wall is completed by osteotomies along the medial orbital floor and lateral nasal wall beneath the inferior turbinate. The septaland posterior incisions are delayed until superior mobilisationis complete, in order tominimise bleeding and maximise access. At this stage haemostasis is secured and temporary packs are placed in the nasopharynx and nasal cavity. The operating table is returned to a horizontal position to avoid air embolism and the frontal craniotomy is performed.

Fig. 33.6 Osteotomies for en bloc ethmoid resection.

A shield-shaped craniotomy measuring approximately 3.0 X 3.Scm is situated at the level of the supraorbital rim so as to include the frontal sinus (Figs 33.5 and 33.6). Bone cuts are made with a rosehead cutting burr or fissure burr through the frontal sinus to ‘blue-line’ the dura. The boneflap is then outfractured, using a curved elevator, andadherentdura is carefully separated to avoid tearing. The bone flap is stored in antibiotic solution for subsequent replacement. The frontal sinus mucosa is removed and additional exposure obtained by removing the remaining posterior wall of the sinus witha rongeur. Dura is widely elevated from the frontal bone and orbital roofs with a Penfield elevator under direct visualisation. This facilitates subsequent access to thejugum of the sphenoid posteriorly. Sharp dissection may be required to separate dura from the foramen caecum and crista galli. If large, the crista galli is removed with a needle-nosed rongeur to facilitate visualisation of the anterior cribriform plate.

Dissection of the cribriformplates is accomplished using theoperating microscope. The olfactory nerves and dural extensions are divided, using an 11 scalpel blade or Mallis scissors. Neurosurgicalpattiesare used to support the frontal lobes and prevent herniation through the dural defects as dissection proceeds posteriorly. A broad, malleable, copper retractor maybe used to gently retract the frontal lobes for more posterior access. Absolute haemostasis is secured by bipolar cautery.Where tumour is found to penetratethe cribriform and involve dura, a margin of normal dura is resected. If intradural extension has occurred, tumour may be separated from the adjacent frontal lobe; otherwise involved brain may be resected together with the tumour. Theolfactorybulbs may be preserved if tumour does not penetrate the cribriform plate. When resection is performedforolfactoryneuroblastoma(aesthesioneuroblastoma), however, resection should routinely include the olfactory bulbs. The anterior and posterior ethmoid arteries are encountered crossing the cribriform plate beneath thedura and these are bipolar-coagulated. Duralelevation is carried posterior to the cribriform plate on to the planum sphenoidale and lesser wings of the sphenoid. Superior mobilisation of the ethmoid complexis now achieved by osteotomies,asshown inFigs 33.2and 33.6. Anteriorly the osteotomies areeasily made, with a

fissure burr, through the frontonasal ducts, across the midline and perpendicular plate of ethmoid to the orbit laterally. The lateral osteotomies are made through the orbital roof, while protecting the periorbita with a malleable retractor inferiorly. If the tumouris unilateral, the contralateralosteotomy is madethroughthe fovea ethmoidalis into theethmoid cells on the uninvolved side, preserving the orbit intact. The posterior osteotomy crosses the planum sphenoidale to include the anterior wallof the sphenoid. Laterally this willbe close to theoptic nerves and theinternalcarotidarteries. To avoidinadvertent injury to these structureswiththe fissure burr,the osteotomies can be outlined with a rosehead burr and completed by rocking the specimen or with a curved osteotome. The osteotome is used to ensure that superior mobilisation is complete. The specimen is now freed inferiorly by dividing the perpendicular plate of the ethmoid from the remainder of the septum. Anteriorly the septal cartilage is easily divided with a 15 blade. Mayo scissors are used to make the inferior cut. Remaining posterior attachments of the lateral nasal wall and sphenoid rostrumare divided withtheMayo scissors andthe specimen is removed via the facial approach. Haemostasis is secured and the cavity inspected for completeness of the resection. Residual ethmoidcells are carefully removed and the remaining mucosa removed fromthesphenoidandmaxillaryantrum. Specimens should be takenfrom all adjacentmarginsforboth frozen and paraffin sections to confirm clearance of the tumour. A large middle- eat tal antrostomy is created in the contralateral maxillary antrum to ensure drainage and to avoid postoperative sinus infection.

Division of the olfactory nerves and sheaths results in a minimal dural defect, two series of holes or longitudinal defects. Theseareprimarilyrepaired by transcranial suturing with interruptedor continuoussilk or with long-lasting absorbable sutures. Afascia ,lata graft large enough tocover the entire bonydefect is then placed over theduralrepair. Fibrin glue isuseful to further seal the dural repair and hold thefascia graft in position. For larger dural defects, repair is achieved with a fascia lata graft placed between the brain and the adjacent dura,to whichit is sutured. Fibrin glue and a second layer of fascia then helps to ensure a watertight repair. As the brain is allowed to re-expand, a thin split-skin

Anterior CraniofacialResection graft is applied inferiorly, covering the fascia lata repair and overlappingthe medial orbital walls. A layer of Sofradex-soaked Gelfoam is placed to support the skin graft and the cavity is packed with 2-inch (Scm) ribbon gauze soaked in Whitehead's varnish (compound iodoform paint in solvent ether). los~re

The frontal-bone flapis replaced and secured with wires or miniplates. If thebonewherethemedialcanthal ligament was attached has been removed, the ligamentis resuspended, using a non-absorbable suture through a drill hole in adjacent bone. The lacrimal duct can be stented, as described for lateral rhinotomy. Theincision is closed with absorbable suturesto the periosteum and subcutaneous layer and nylonsutures to theskin. A moderate pressure dressing over an eye pad is applied for 24h.

1 If a lumbar drain wasplaced, it is removed at completion of the procedure. Thevolume of cerebrospinal fluid (CSF) removed may be replaced with normal saline to gnsure brain re-expansion prior to closure. 2 Patientsarekept lying flat for48 h andthenare gradually allowed to elevate and mobilise over 5 days. 3 Fluid intake is restricted to 1500-2000ml daily total for 48 h. 4 The urinary catheter is removed on the second day. 5 Facial sutures are removed after S-? days. 6 The nasal pack is removed at 10-14 days under general anaesthesia and the cavity is inspected. 7' Nasolacrimal stents are removed after 2-3 months,

~ r a ~ s f a c iapproach al The transcranial part of CFR may be accomplished via bicoronal a incision and frontal craniotomy. The bicoronal incision allowswide access to thefrontal bone and preservation of pericraniumfor use asa vascularised flap to repairtheanterior-fossa defect (Snyderman et al., 1990).This facilitates earlypostoperative radiation therapy when indicated. Placed behindthehairline,the incision is cosmetically very acceptable.Thebicoronalscalp incision should begin laterally,abovethepinnae, preserving theanterior branches of the superficial temporal arteries. The scalp, including thegalea, is carefully elevated, initially leaving

239

the pericranium on the bone. The pericranium is then elevated, ensuring sufficient length (at least 10cm, preferably 1Scm)forthe subsequent flap repair. The pericranium is elevated at least to the supraorbitalridge, unless the craniotomy is to bevia a transfrontal-sinus osteoplastic flap. Caremust be taken to preserve the supraorbital and supratrochlear vessels. The pericranial flap may be tacked to the scalp flap to protect it during the subsequent procedure. The site and size of the frontal Craniotomy may be varied according to the extent of disease and resection necessary (Schramm, 1991).Many centres in the USA favour alarge bifrontal craniotomy. Although providing excellent access to theanterior-fossa floor, the wide exposure is usually unnecessary and increases the potential for complications. Excessive frontal-lobe retraction is possible and may result in permanent neurological dysfunction, particularly in irradiated patients. The extensive dural exposure increases the risk of dural tears and CSF leakage. Failure of brainre-expansion may potentiate extradural collection of haematoma or pneurnocephalus. Epidural infection inevitably requires that the frontal-boneflap is removed, resulting in a gross cosmetic defect. In several series, this has occurred in 10% of cases. Preferably a transfrontal-sinus Craniotomy is utilised. When the frontal sinus is large, the anterior table may be removed with a bevelled osteotomy around an X-ray template,either as a free boneflap or pedicled on pericranium as an osteoplastic flap. After removal of the sinus mucosa, the posterior table is thinned with a burr and removed. Removal should commence laterally and the dura must be carefully elevated to prevent injury to the sagittal sinus. Sufficient access is thus achieved to allow ethmoid resection and dural repair. If the frontal sinus is small, a Craniotomy is made as described for the transfacial approach. The base can be made wider so as to allow placement of a pericranial flap that is broad enough not to compromise vascularity. Other variations in site and size of the craniotomy boneflap can be made, as determined by the extent of resection and exposure necessary. For example, the glabellar bone can be included with the bone flap, which allows unobstructed exposure at cribriform level, while minimising frontal-lobe retraction. Duralelevation,cribriform-plateexposureandthe superior bone cuts are made as described above. A free pericranial patch may be used instead of fascia lata, if there is a dural defect to repair. After resection is complete and dura repaired, the pericranial flap is placed through the craniotomy to separate the anterior fossa from the nasal cavity (Fig. 33.7). The pericranial flap is

) ” Fig. 33.7 Placement of pericranial flap repair.

Fig. 33.8 Alternative placement of pericranial flap.

tucked beneath the dura over the planum sphenoidale posteriorly, where it is secured by suturing via the lateral rhinotomyexposure. At this stage, thebrain is being allowed to re-expand and retraction must be avoided. Laterally the pericranial flap should overlie the orbital roofs. Anteriorly a redundant portionis left to cover the posteroinferior aspect of the bone flap and fill the potential space where thefrontal sinus was removed. The bone flap is replaced and secured to the superior edge so as not to compress the pericranial flap inferiorly. An alternative is to place the pericranial flap over the superior aspect of thefrontal-bone flap (Fig. 33.8). Technically this is more difficult, as the pericranial flap must be positioned and secured from below, but it has the advantage that the frontal-sinus potential space is exteriorised into the nasal cavity. This may reduce the incidence of intracranial complications. A split-thickness skin or dermal graft rnay be applied to the nasal surface of thepericranial flap. This is not essential, as the flap will mucosalise without skin grafting. If haemostasis is meticulous it is not necessary to pack the nasal cavity at completion of the procedure. Whenabicoronalapproach is used superiorly, the lateral rhinotomy incision rnay be modified. Periosteum can be left attached to thenasal bone and access achieved by osteotomy and reflection of the nasal bone with the medial skin flap. If uninvolved by tumour, the

medial infraorbital rim and frontal process of the maxilla may also be left attached to the nasal bone and reflected. This allows stable fixation during reconstruction and avoids nasal or facial deformity. Contralateral medial orbital exploration is best achieved via a separate Lynch incision on that side, so that periosteal blood supply to the nasal bone is preserved intact.

For smaller tumours notinvolving the anterior ethmoid, it is possible to avoid facial incision altogether by bicoronal and midfacial degloving approaches.

Orbital exenteration andlor maxillectomy is combined with craniofacial resection when necessary. The lateralrhinotomy incision is extended by a WeberFergusson, lip-splitting or eyelid incision as required. The orbital defect may be managed by primary closure of the eyelids, with without or temporalisa muscle flap placed via lateralorbitotomy. Tumour involvement sometimes necessitates resection of the orbital roof as well asthecribriform plates. In such cases a large bony defect results. It is recommended

Anterior CraniofacialResection thattheanterior-fossaanddural repair be supported by afree microvascular muscle graft. Latissimus dorsi or rectus abdominus free flaps are ideal andcan be placed in theorbital defect. This reduces thechance o f delayed breakdown of the anterior-fossarepair, particularly postoperative if radiation therapy is necessary.

Accepted sequelae

Delayed

1 Osteomyelitis. 2 Sinusitis. 3 Skin-flapnecrosis. 4 Necrosis o f anterior-fossa/dural repair. 5 Encephalocele. 6 Hydrocephalus. 7 Frontal-lobe dysfunction.

Anosmia

Orbital

There will be a single large sinonasal cavity, with potential crustingrequiringlifelong care(alkalinedouches b.d. and intermittent out-patient decrusting).

1 Visual loss. 2 Diplopia. 3 Dystopia. 4 Enophthalmus. 5 Corneal injury.

COmpiiCa&iOnS(Richtsmeier et al., 1992) Early

Neurological 1 Cerebraloedema. 2 Cerebralinfarct. 3 Intracranialhaemorrhage. 4 Pneumocephalus. 5 CSFleak. 6 Diabetes insipidus. 7 Seizures. Infective 1 Meningitis. 2 Epidural abcess. 3 Woundinfection.

24 I

References Cheeseman AD, Lund VJ & Howard DJ (1986) Craniofacial resection for tumors of the nasal cavity and paranasal sinuses. h e a d Neck Surg. 8, 429-35. Levine PA, Frierson HF, Marc Stewart F, Mills SE, Fechner FE & Cantreil RW (1987) Sinonasal undifferentiated carcinoma: a distinctive and highly aggressive neoplasm. Laryngoscope 97, 905-8. Price JC, Johns ME, Loury M et al. (1988) The pericranial flap for reconstruction of anterior skull base defects. Laryngoscope 112, 1159-64. Richtsmeier WJ, Briggs RJS, Koch WM et al. (1992) Early outcome and complications of anterior craniofacial resection. Arch. Otolaryngol. Head Neck Surg. 118, 913-17. Schramm VL (1991) Anterior craniofacial resection. In: Jackson CG (ed.) Surgery of Skull Base Tumors. New York, Churchill Livingstone, pp. 67-83. Snyderman CH, Janecka IV, Sekhar LN et al. (1990) Anterior cranial base reconstruction: role galea1 of and pericranial flaps. Laryngoscope 100, 607-614. Sundaresan N & Shah JP (1988) Craniofacial resection for anterior skull base tumors. Head Neck Surg. 10, 221-4.

ans-sphenoidal Hypophysectomy ALAN P. JOHNSON

The procedure described is the transethmoidal approach to the sphenoid sinus. The trans-septal approach is also widely used, and will be discussed and compared briefly at the end of the chapter.

cati

ans-sphenoidal

Trans-sphenoidalsurgerywastraditionally reserved for smaller pituitary tumours. Adenomas are classified intomicroadenomas ( < l 0 mm diameter) and macroadenomas (> 10mm diameter). All micro- and many macroadenomas are now considered to be treatable by trans-sphenoidal surgery, but those unsuitable will be discussed under Contraindications. Endocrine disor ers caused by function in^ pituitary adenomas

The functioning adenomas are as follows: Prolactinoma (prolactin-producing adenoma)

Thesearethecommonestadenomas.Theyoften respond well to treatment with dopamine agonists, such as bromocriptine. Surgery is reserved for: 1 those prolactinomas which do not respond to medication; 2 patients who are intolerant of the medication; 3 unresponsivemacroadenomascausingintracranial complications. Acromegaly (growth-hormone-producing adenoma)

This is the second most common adenoma, Octreotide

(Sandostatin) has become available to treat this condition medically, but this drug is still in the process of development. Surgery is effective-most tumoursare macroadenomas. Cushing’s disease (ACTH-producing adenoma)

The adenomas causing Cushing’s disease are almost always microadenomas, andmay even occurin an ‘emptysella’, with the disease being caused by a tiny adenoma in the pituitary remnant. Careful endocrine assessment is essential to ensure that the syndrome is being caused by an adenoma in the pituitary, not in the adrenal or from an ectopic source (e.g. oat-cell carcinoma of the lung). Nelson’s syndrome

If a patient has an ACTH-producing pituitary adenoma and is treated by an adrenalectomy, he/she may develop Nelson’s syndrome, with hyperpigmentation andan expandingpituitaryadenomacausing palsies of the extraocular muscles by invasion of the cavernous sinus. Surgery will debulk these tumours,butradiotherapy should be used as well because of the invasion of the cavernous sinus, which is unlikely to be cleared by surgery alone. Rare adenomas such as TSH-producing adenoma

These can be effectively treated by hypophysectomy.

~~ans-spheno~dal Hypophysectomy

243

Compression of intracranial structures

Optic chiasma

Local

Chiasma1 compression typically causes gradual loss of vision, initially inthesuperiortemporalquadrants. There can be a suddenloss of vision because of bleeding into a pre-existing adenoma. If treated promptly, the recovery is good.

l Acute infections of the nose or sinuses. 2 Malaeration of the sphenoid sinus. This is a stated contraindication, but the author has not encountered it in 120 cases. 3 Suprasellar spread or cavernous-sinus invasion. Suprasellar extension of an intrasellar tumour may well by amenable to trans-sphenoidal surgery, but such tumours need carefulconsideration. If thetumour is spherical, it often drops down into the fossa when the lower part is removed. If it is bilobed, the upper lobe will not be as accessible from below and such tumours are better managedby a transfrontal approach. Tumour extension laterallyinto thecavernous sinusis not readily accessible by anyapproach,butcan be partially removed trans-sphenoidally. 4 Carotidaneurysm. If this is suspected,itmust be excluded by angiography.

Normal pituitary gland

Hypotituitarism can be caused by compression or replacement of the normal gland. For this to occur, the tumour is usually large enoughto compress other structures as well. Third ventricle and hypothalamus

An expanding tumour can disturb the flow of cerebrospinal fluid (CSF) by compressing the third ventricle.

General

Nerves in the cavernous sinus

These are rarely damaged by an expanding adenoma, and, if a pituitarylesion is causing an oculomotor palsy, consider alternative pathology, such as an aneurysm. Notethatmacroadenomas,pituitary cysts, other tumours,suchascraniopharyngioma,chordomaor metastatic carcinoma, or aneurysms may present as expanding lesions in this site. Theymaypresentwith symptoms or as an incidental finding on ascanperformed for another reason. Cerebrospinal fluid leaks from the pituitary fossa

Thesecanoccurfromthisregion because of the following: 1 empty-sella syndrome; 2 after pituitary surgery -either early or late; 3 post-traumatic; 4 glioma. The trans-sphenoidal approach is excellent for closure of CSF leaks coming through the sphenoid sinuses.

1 Risk of haemorrhage. Bleeding duringsurgery is mainly venous but it can be profuse. Any tendency to bleed is a contraindication to this surgery. 2 Poorgeneralhealth.Themorbidityfromtranssphenoidal surgery is significantly less than for transfrontal surgery, but thisis major surgery, and the patient should be as fit as possible.

Preoperative management These patients are almost alwaysreferred to the surgeon by another hospital doctor, most frequently an endocrinologist or aneurologist.They have usually been fully investigated and the diagnosis made, but isitessential for the surgeon to be satisfied that the diagnosis is correct and that the indication for surgery is appropriate. Preoperative examination

This is important todetect any nasalsepsis or abnormality which will complicate the approach. Imaging

Management of hormonally dependent tumours and diabetic retinopathy

Thiswaspopular,buthypophysectomy used for this purpose.

is no longer

C T scans

Axial and coronal CT scans show the bone and sinus detail. Sagittal reformats in the midline show the anterior aspect of the pituitary fossa.

244

Chapter 34

MRI scans MRI is particularly valuable because it is best for softtissue contrast and more like:ly than CT todemonstrate a microadenoma. It alsodem.onstrates extrasellar extension and the optic chiasma well. Angiography This is indicated if an aneurysm is suspected. A plain lateral view of the sinuses This is more or less to scale, and is useful as a reference during surgery.

If there is any suprasellar spread on imaging or if there is any visual disturbance,the visual fields should be formally recorded pre- and postoperatively.

physectomy The anatomy for the approach to the pituitaryis as for an external ethmoidectomy. The surgeon needs to be thoroughly conversant with the anatomy of the nose, ethmoid sinuses, and the medial wall and apex of the orbit. Particular points to note are as follows: 1 The anterior ethmoidal artery enters the nose from the orbit through the frontoethmoidal suture line 2.5cm posterior to the nasion. This is in the angle between the medial wall and the roof of the orbit. The level of the artery is below the floor of the anterior cranial fossa in the ethmoidal cells, but it may be above the level of the cribriform plate, medial to the anterior attachment of the middle turbinate (Fig. 34.1). 2 Theoptic nerve may indentthemostposterior ethmoid and the sphenoid sinuses. It can be vulnerable here if the surgeon dissects too far laterally. 3 The sphenoid sinus ostium is located halfway up the anterior, nasalaspect of the sphenoid sinus wall, several millimetres lateral to the attachment with the vomer. 4 Thecarotidarteries may be visible withinthe sphenoid sinus, where they may indent the lateral walls below the pituitary fossa. 5 Anatomy of the pituitary. The gland lies within the bony pituitary fossa, with one cavernous sinus on each side of it and the dorsum 'sellae posterior to it. It is encased in dura onall sides except superiorly, where the stalk of the gland enters through the diaphragmasellae.

Fig. 34.1 Trace of a coronal CT scan 2.5cm posterior to the nasion. A, level at which the anterior ethmoidal arteries leave the orbits; B,level of the cribriform plate.

Within the fossa, the pia and arachnoid have fused with the dura and there is no subarachnoid space. The anterior lobe is cellular and vascular, and the smaller posterior lobe isless vascular and consists mainly of unmyelinated nerve fibres, which are attached to their cell bodies in the hypothalamus. The blood supply is from twigs of the internal carotid and anterior cerebral arteries, and the anterior lobe also receives blood from the hypothalamus, via a portal venous system. Venous drainage is into the cavernous sinuses.

Operative technique Preparation

1 Topicalvasoconstriction in the nose is essential. Xylometazoline or cocaine spray is satisfactory. 2 Anaesthesia: general anaesthesia is required, with oral endotracheal intubation. The patient should be ventilated and mildly hypotensive. 3 Prophylactic antibiotic cover is essential. Coamoxiclav(Augmentin) l.2 g is given intravenously on induction, and repeated S-hourly for 48 h. Hydocortisone cover is also given, according tothe regimen given in the postoperative managementsection. 4 Positioning of the patient: the headis slightly elevated and supported in a head ring, so that it can be moved during the operation but is stable. The operating table should be radiolucent so that the patient canbe screened on the table if necessary. incision

The skin is preparedwithaqueous chlorhexidine. The head is draped so that the nose, eyes and forehead are exposed, and the eyes are held shut with Steristrips.

Fig. 34.2 Skin incision for transethmoidal approach.

A curved incision is made from the medial end of the right eyebrow to the inferior margin of nasal bone. The incision mustrunanterior to themidpoint, between the medial canthus and the nasion (Fig. 34.2), because this prevents unsightly webbing of the scar. Incise right down to bone, using the full length of the incision, and obtain haemostasis. If the surgeon is right-handed, it is easier to maketheapproachthroughtheright side. However, if the patient has a lesion which requires an approach through the left, or if the patient is blind or has poorsight in the left eye and good vision in the right, it is perfectly possible to do the approach through the left ethmoids.

The periosteum is dissected off the bone. At the point of incision, this isfirmly adherent and a small, sharp, periosteal elevator is needed. Once the anterior lacrimal crest is exposed, the periosteum posterior to this strips readily off the medial wall of the orbit. A self-retaining retractor can be inserted to hold the orbital contents laterally, but it is important to avoid putting too much pressure on the eye. The author prefers the Talbot retractor to the more widely used Ferris Smith, because it has a good self-retaining ratchet and the handles can be rotated andclipped to the head towels to maintain good access.

The frontoethmoidal suture line is identified in the superomedial corner of the orbit. The anterior ethmoidalartery is found about2.5cm fromthe nasion, running from the orbit to the nose. It should be dissected sufficiently to be able to ligate and divide it safely with diathermy or clips (titanium is essential because thepatient may need MRI in the future). The artery is an important reference point, as it is the posteriorsuperior limit of the excision of the lamina papyracea (Fig. 34.3). A rectangle of bone is removed fromthe medial orbital wall, as illustrated in Fig. 34.3.Theanterior ethmoidal artery is the posterior superior limit of the resection. The anterior ethmoidal cells are opened and cleared in aposteromedialdirection until the nose is entered. It is essential not to go superiorly or through the attachment of the front half of the middle turbinate, because the cribriform plate is vulnerable (Fig. 34.1). It is important to work posteromedially until the nose is entered, and then to identify the sphenoethmoidal recess and thesphenoidostium. These arefound by using the rounded end of a Freer’s dissector passed through the right nostril, and working gently up the face of the sphenoid 2-3mm lateral to the midline. About 1cm above the inferior attachment of the vomer, the ostium can be gently probed and then seen. The ethmoids can then be cleared and, if necessary, the posterior part of the middle turbinate removed, to bring thefrontof the sphenoid into full view. At the superior limit of the ethmoidal cells, thewhiter bone of the floor of the anterior cranial fossa can be seen. Note that the optic nerve may lie in the superolateral part of the posterior ethmoid cells. The frontof the sphenoidis removed using a fine bone punch, such as the Hardy sella punch, working inferiorly first. The interior of the sphenoid sinus and

Fig. 34.3 Window into ethmoids.

Fig. 34.4 Axial view of access to pituitary via ethmoids.

the pituitary bulge are exposed. Careful review of the CT scans will demonstrate the position of the septum between the two sphenoid sinuses. The septum is removed if this will improve access. The posterior part of the nasal septum is removed by perforating it just anterior totherostrum of the vomer, thus allowing the surgeon to see the left sphenoidostium.The left sphenoid is then opened, allowing a good view of the whole pituitary fossa (Fig. 34.4). Ideally the surgeon should be able to see up to the point where the front wall of thepituitary fossa meets the roof of the sphenoid, and laterally to where it meets the lateralsides of thesphenoid sinuses. Thecarotidarteries may be visible in the lateral walls below the pituitary fossa. If thesinus mucosa is thick (a common finding in acromegaly), it canbe reflected inferiorly and held down with a small neurosurgical swab, and used to complete the closure at the end of the operation.

The surgeon needs to be sure of the midline. The rostrum of the vomer is a consistent midline feature. The microscope is used, and the surgeon can sit if the head is turned and 4.5" eyepieces are used. The bony anterior wall of the pituitary fossa is removed. If the bone is thin or eroded, it can be removed by pressing through it and picking it up with Hardy sella punches. If it is thick, a drill witha large burr isused untilenough dura is exposed to allow access for a punch. The bony defect is enlarged in the extradural plane to allow adequate access, but to a minimum of 1cm2. The dura covering the pituitary contains veins connecting the cavernoussinuses; these are oftenvisible and

should be avoided when incising intothe fossa. A cruciate or T-shaped incision may be made. The pattern is marked out with a coagulation diathermy on a low setting, and then incised withcuttingdiathermy or microdissection scissors. Once the dura is incised, a plane can be developed between the gland and the layers of the dura. The location and size of the tumour will then determine how the surgeon proceeds. If imaging hasdemonstratedthe location of amicroadenoma,this part of thegland is dissected. It is easiest to dissect along the floor until theposterior wall of the fossa is felt, thenalong theappropriate side and finally over thetop. If an obviousadenoma is identified at operation, remove this and a rim of normal gland for histology. Not all microadenomas are discrete, and imaging does not identify them all. The first operation is also much easier than any revision operations, and so the surgeon should aim to cure the disease rather than leave adenomatous tissue behind. If there is a macroadenoma, and particularly if there is significant suprasellarspread,thetumour may be opened and the fossa emptied. If the tumour is soft, the superior portion will drop down as the lower portion is removed, and in this way the tumour may be cleared. Raising the intracranial pressure at this point brings the superior extension down into view. When the superior surface of thegland is dissected, the very delicate diaphragma sellae can be seen as a blue pulsatile membrane, and the gland can be gently dissected off this, Gentle dissection will minimise CSF leakage. Closure

The author uses Lyostypt collagen foam to packthe pituitary fossa. Muscle was used but there is morbidity associated with the donor site, and collagen foam is just as effective. If there is venous bleeding during surgery, this stops rapidly withpacking, which does not need to be tight. A piece of bone from the septum or turbinate can be shaped and used to rebuild the front of the fossa. The sphenoid mucosa or turbinate mucosa can then be used to patch the area and covered with more Lyostypt; then a 1.25cm X 1m bismuth, iodoform and paraffin paste (BIPP) pack can be packed carefully intothe sphenoid, and into the right side of the nose. Seldom is a pack required in the left side if the sphenoid is adequately packed. The incision is closed in two layers, 4/0 Vicryl to the periosteum and interrupted 510 Ethilon to skin. The skin sutures should be put in to obtain exact apposition of the skin edges, and should be removed at 3 to 4 days to

~ ~ a n s - s p b e n o i~dy~pl o p b y s e ~ ~ o m247 y minimise scarring. If the incision is correctly located and is closed in this way, it will be virtually invisible in 6 months. Alight dressing rnay be needed to stopany ooze entering the eye, but nothing is achieved by putting on a head bandage or eye patch, which merely obscures a developing haematoma.

Postoperative management Neurological observations

Routine neurological observations should be carried out for the first 24h. On recovering from the anaesthetic, the patient is usually fully alert and orientated. There is little pain in the nose, but headache occurs if there was a significant loss of CSF on the table. Occasionally an orbital haematoma can develop, and so the eye must be watched for this. Fluid balance

An accurate fluid balance is important because the patient may develop a diuresis, particularly if the posterior pituitary has been injured or there was traction on the pituitary stalk. Itdoes not start until the first postoperative day. In the event of a diuresis (> 4 L urine output/ 24 h),if the urine output is >250 ml/h for 3h, give 1pg of DDAVP. The diuresis may not be due to diabetes insipidus, and so donot give DDAVP if theserum sodium is less than 145mmol/L or severe sodium depletion rnay result. Daily electrolyte measurement is required to monitor this. Steroid replacement

Steroid cover is used for all patients, and the regimen is as below. Day of surgery hydrocortisone 50mg IV/IM 6-hourly 1st day hydrocortisone 50 mg IV/IM 6-hourly 2nd day hydrocortisone 50 mg IV/IM 6-hourly 3rd day hydrocortisone 50 mg IVfiMlorally 8-hourly 4th day hydrocortisone 50mg IVlIMlorally 12-hourly 5th day hydrocortisone 50 mg mane, 20mg nocte 6th day hydrocortisone 30mg mane, 20mg nocte 7th day hydrocortisone 20 mg mane, 1Omg nocte Thereafter hydrocortisone 20 mg mane, 1Omg nocte The hydrocortisone must not be stopped until the pituitaryfunctionhas been formally assessed some weeks after surgery.

The haemoglobin is checked prior to discharge, and sooner if necessary. The nasal pack is removed at 5 days if there is no CSF leak. Postoperative visual-field testing can be arranged if the surgery was for chiasma1 compression. There is usually an early response to decompression. Patients go home 6-7 days postoperatively if all is well, on steroids and with a steroid warning card.

Complications Peroperative

1 Bleeding: this is venous, from the intercavernous connecting veins, and can be troublesome because it obscures the view of the surgeon. It is often possible to compress or pack the bleeding point with Lyostypt or a similar haemostatic material, or to clip it to the floor of the fossa withatitanium Ligaclip. Arterial bleeding from the carotid is possible, but must be avoided. Packing the fossa at theend of theprocedurestopsthe venous bleeding. 2 CSF leak from the cribriform plate area can occur if the surgeon is too high and medial anteriorly, and must be recognised and patched from below. 3 Optic-nerve injury is possible, but direct injury is avoided by remaining within the pituitary fossa. Early postoperative complications

1 Orbital haematoma can occur, and may need to be drained. 2 Diuresis: this is managed as described above and it usually settles within days, but, if it persists, nasal desmopressin is administered to control diabetes insipidus. 3 CSF leak rnay be troublesome, and indicates an inadequate seal inthe fossa. Antibiotic cover should be continued. It oftensettles within days, but, if it does not, lumbar puncture, lumbar drainage or repacking may be required. 4 Meningitis is unusual, because of prophylactic antibiotics. Patients can suffer from meningeal irritation several days postoperatively because of blood in the CSF. If meningitis is suspected, lumbarpuncture is done to make the diagnosis, and treatment started. 5 Crusting in the nose occurs intheethmoids and sphenoid, but settles with time. Late postoperative complications

1 Recurrence of the adenoma is the commonest complication,andlong-termfollow-up is important,with

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biochemical assessment and further imaging when indicated. 2 Hypopituitarism. 3 Diabetes insipidus. 4 Frontal sinusitis may arise if the frontonasal duct is damaged in the approach.

~ ~ t e r n a t i vtechniques e Trans-septal transllsphenoidal approach

This approach and variants of it arepopularamong neurosurgeons. An incision is made across the incisive fossae under the upper lip, and the septum is dissected in the subperichondrial and subperiosteal planes. The septum can be preserved and displaced laterally, and the sphenoid opened in the midline. A self-retaining retractor is inserted to maintain access during the procedure. Disadvantages 1 Longer route to the pituitary fossa. 2 Line of vision is the same as the route for instrumentation. In the transethmoidal approach, the instruments are used throughthe nose while thesurgeon views through the ethmoids.

3 Narrower access: the transethmoidal approach allows a wider angle of vision to thefront sphenoid.

of the

Advantages 1 No facial scar. However, if the technique described above is used in the transethmoidal technique, scarring is minimal. 2 A midline approach gives a symmetrical view of thegland. In thetransethmoidal technique, arightsided approach gives a better view of the left side of the gland. 3 The lower angle of approach gives a better view of the roof of the sphenoid sinus and makes suprasellar extensions more accessible by this route.

Further reading Hardy J (1982) Trans-sphenoidal hypophysectomy. In: Youmans JR (ed.) Neurological Surgery, Vol. 6. Philadelphia, W.B. Saunders, pp. 3959-72. Williams RA (1983) Trans-sphenoidal hypophysectomy. In: Ballantyne JC & Harrison DFN (eds) Rob & Smith’s Operative Surgery-Nose andThroat,4th edn.London,Butterworths,pp. 170-7.

Surgery for Cerebrospinal-fluid Rhinorrhoea CHRIS A. MILFORD

indications Leakage of cerebrospinal fluid (CSF)fromthe nose is symptom a of failed containment within the subarachnoidcompartment and its origin may be fromany of thecranial fossae. It may occur from the anterior cranial fossa through the frontal, sphenoidal or ethmoidal sinuses or directly through the cribriform plate. Escape of CSF from the middle and posterior fossae may occur directly via thesphenoid sinus or indirectly via themastoidair cellslmiddle ear through the Eustachian tube (CSF otorhinorrhoea). In this chapter,theproblem of CSF otorhinorrhoea will not be addressed and only the leakage of CSF into the nose directly or via theparanasal sinuses will be dealt with. Although the actualloss of CSF itself isof no particular consequence, a persistent dural fistula represents a persistent hazard for a potentially fatal purulent meningitis. Persistent CSF rhinorrhoea is therefore an absolute indication for the surgical repair of the leak.

Preoperative management The aetiology of CSF rhinorrhoea may be traumatic or non-traumatic (spontaneous). The evaluation of a patient suspected of having CSF rhinorrhoea should do the following: 1 Confirm the presence of the leak (confirm that the fluid is CSF). 2 Demonstrate the cause whenever possible. 3 Identify the site of the leak. Accurate definition of the leakage site is undoubtedly the most important factorin successful surgical treatment of this difficult problem. Contrast CT cisternography and intrathecal dye studies

(fluorescein) appear to be the most useful investigations for localisation.

Anatomy of the anterior skull base The bone of the anterior skull base is thin with densely adherent dura andhence trauma in this site often results in dural tears and CSF leaks. The most common location of anterior fistulae is the region of the fovea ethmoidalis and the posterior frontal sinus wall. In the region of the fovea ethmoidalis, the ‘weakest’ point is where the thick fovea ethmoidalis (that partof the frontal bone forming the roof of the ethmoid) joins the thin lateral lamella of the cribriform plate medially, and in particular where the anterior ethmoidal artery passes into the anterior cranial fossa (Fig. 35.1). The bone in the vicinity of the anterior ethmoidal artery is 10 times thinner than the neighbouring roof.

Operative technique Operative approaches are divided into intracranial and extracranial. Intracranial procedures will not be dealt with, although this may be the approach of choice in some leaks that cannot be localised (and especially if they cannot be lateralised). The particular extracranial technique adopted is dependent upon the site, size and nature of the leak and may be via a conventional external approach or, in some cases, may involve endoscopic techniques. Whichever technique is used, the principle used in repair is the same. Firstly, a free graft of tissue is used to mechanically stop the flow of CSF so that the rest of the repair can proceed and the overlying layers will not be disrupted. This initial free graft is best placed between the

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Fig. 35.1 Anatomy of the anterior skull base. 1, fovea ethmoidalis; 2, lateral lamella of cribriform plate; 3, ophthalmic artery; 4, anterior ethmoidal artery.

dura and bone, i.e. thegraft is ‘tucked in’ abovethe bony skull base on the intracranial side. Next, ideally, a vascularised graft is placed over the defect to bring in ablood supply, fibrin and the cellular elements of wound healing, e.g. a pedicled flap of nasal mucosa. Finally, atemporarysupportive dressing is required to keep the repair in place in the immediate postoperative period. The tviro traditional external approaches are as follows: 1 leakage of CSF throughthefrontalsinus may be approached via the anterior osteoplastic-flap procedure; 2 leakage of CSF through the cribriform platehoof of ethmoidhphenoid may be repaired via an external ethmoidectomy approach.

adrenaline, and both eyes are closed withtemporary tarsorrhaphysutures of 5/0 silk to avoid accidental damage to the cornea. The place of prophylactic antibiotics in the presence of CSF rhinorrhoea is still controversial and their use has been both condoned and condemned. The place of an indwelling subarachnoid lumbar drain in the postoperative period is not clear but would seem a reasonable option in the hopeof improving the success rate for this type of surgery. The drain canbe placed after induction and prior to the operation, and if used then prophylactic antibiotics are indicated until the drain is removed (510 days postoperatively). A Silastic cut-out (template) of the frontal sinuses is made preoperatively from the occipitomental view of the sinus X-rays. Thecut-out is placed in sterilising solution prior to surgery. The skin of the abdomen or thigh is prepared so that agraft of fatandlor fascia lata may be obtained if required. Incision

Although an eyebrow incision along the upper margin of the ipsilateral eyebrow can be used for a unilateral operation,the author believes abilateralosteoplastic flap is the procedure of choice, because of the better

Leakage of CSF through the frontal sinus

Preparation

The operation is performed under a general anaesthetic (GA) given via an oral endotracheal tube (ET) with a pharyngeal pack, with the patient supine and head elevated. The nose is packed with 1cm ribbon gauze soaked in a mixture of 1m1of 1:1000 adrenaline and 2ml of 5% cocaine solution, in an attempt toreduce the vascularity of the nasalmucosa. The skin is cleaned with aqueous chlorhexidine and thehead is draped with towels to exclude the hair, mouth and ear. Theincision line is infiltrated with 0.5% lignocaine and 1:200 000

Fig. 35.2 The eyebrow (spectacle) or coronal incision.

Surgery for ~erebrospinal-~uid Rhinorrhoea

Fig. 35.3 Procedure for osteoplastic flaps. After Rob 6 Smith’s Operative Surgery-Head and Neck (1983). IA McGregor and DJ Howard (eds).

qI

the supraorbital and supratrochlear vessels). This flap may be used forrepair of theanteriorcranial floor, following anterior craniofacial resection, and it can beused in this situation as avascularised flap to repaidline the posterior wall and floor of the frontal sinus in the presence of a CSF leak into this sinus (Fig. 35.3). 2 The X-ray template is taken from the sterilising soluti6n, rinsed with saline and placed over the frontalbone. A pencil is used to outline the template, 2mm a rosehead or fissure burr is used to follow the outline of the template (cuttingjust inside the line to ensure the incision is within the limits of the sinus) and the‘incision’ is gradually deepened until the frontal sinus is entered. Superiorly, the bone is bevelled obliquely as much as possible so as to ensure an accuratereapproximation of the osteoplastic flap and to prevent the bone falling in on replacement (Fig. 35.4). Holes can be made in the bone flap and corresponding margin of the frontal bone to facilitate replacement of the bone flap with heavy Vicryl ties (alternatively the miniplate fixation system can be used) at the end of the procedure. 3 The bone flap is then elevated at the superior aspect and, as the flap reflects downwards and forwards, there is a fracture across the floor of the frontal sinuses (the

access. For the bilateral osteoplastic frontalsinus procedure, the eyebrow (spectacle)or coronal incision can be used (Fig. 35.2). The eyebrowincision should be made along the entire length of the upper marginof the eyebrowand extended horizontally over the glabella. The coronal incision is made approximately 1 inch (2.5 cm)behind the anterior hairline. The bilateral eyebrow flap is elevated superiorly in a plane between thefrontalis muscle and the periosteum over the frontal bone, taking care not to incise the periosteum.The coronalflap is elevated in the same plane and reflected inferiorly over the face, exposing both supraorbital rims and the nasal process of the frontal bone (avoiding damage to the supraorbital and supratrochlear nerves). Since bleeding is much more of a problem with the coronal incision, neurosurgical haemostatic clips facilitate this approach. Procedure

1 Although the original description for the osteoplastic flap describes making an incision in theperiosteum (pericranium) andbone around the outlineof the frontal sinus, using the X-ray template, the author recommends adoptinga modification which involves first raising arectangularpericranial flap with its base at the supraorbital region (thus receiving its blood supply from

Fig. 35.4 Bone i s bevelled obliquely. After Rob 6 Smith’s Operative Surgery-Head and Neck (1983). IA McGregor and DJ Howard (eds).

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Chapter 35 Closure

1 In order to allow the pericranial flap to pass into the sinus easily, aslot may be created by trimmingthe inferior edge of the osteoplastic flap before returning it to its original position (the ‘letter-box technique’). The osteoplastic flap may be secured with heavy Vicryl sutures passed through holes made with a fissure burr. Thecoronal incision is suturedwitha deep layer of absorbable (310 catgut)sutures and interrupted skin sutures of 4 0 Prolene, with a small suction drain left in place. 2 The tarsorrhaphy sutures areremoved and a pressure dressing, to remain in place for 72 h, is placed over the forehead. Fig. 35.5 Free fat graft used to obliterate sinus on top of the pericranial flap.

interfrontal septum has to be divided with a chisel or curved osteotome to allow this). The supraorbital rims and glabella can be particularly thick in men, and a separate cut in the nasion may be helpful in achieving this fracture at the lower end.Whenthefracture is completed and the periosteum has been elevated from the frontal bone, the bone flap can be removed and kept in a betadine solution until the procedure is complete and it is time for the bone to be replaced (separation of the bone flap from its overlying periosteum and its removal does not appear tocompromise itsviability when it is replaced). 4 Once the osteoplasticflap has been removed, the interior of both frontalsinuses is inspected for thesite of the leak. A careful look for anything that pulsates is essential: CSF or anything else communicating with the cranial cavity, such as an arachnoid protrusion, transmits pulsations of the brain. The mucous membrane lining of the frontal sinus is removed, the bone being burred if necessary to remove all traces of mucosa. Posterior table bone can be removed at the site of the leak, and the dura can be repaired directly or a free pericranial graft placed over the site of the leak and tucked in behind the bony margins of the posterior wall. The use of tissue glue has been shown to improve results of repair of CSF fistulae. The inferiorly based pericranial flap may then be placed over the floor of the sinus/posteriorwall to seal the sinus from the nasal cavity. A free fat graft can then be used to obliterate the sinuson topof the pericranial flap (Fig. 35.5).

Postoperative management

Thepatient is nursed in bed forthe first 5 days postoperatively, with the lumbar drainon free drainage. He/she is advised to avoid coughing, sneezing and straining dueto physical activity. At the endof this time, the drain is clamped and, if there is no evidence of a recurrence of the CSF leak, the drain is removed. Following this, the patient is allowed to mobilise slowly and theantibioticsare discontinued afterafurther 5 days. Complications

l Failure to seal the CSF leak.

2 Bony depression of the osteoplastic flap, resulting in cosmetic deformity. 3 Haemorrhage, with haematoma formation under the flap. 4 Infection of the.primary site (osteomyelitis of the frontal bone flap) or fat donor site. Leakage of cerebrospinal fluid through cribriform plate/roof of ethmoid/sphenoid sinus

Preparation

See above. Incision

A 1 inch (2.5cm) curved incision is made halfway between the inner canthus and the anterior aspect of the nasal ridge. It may be extended under the eyebrow to facilitate access.

Surgery f o r Cerebrospinal-fluidRhinorrhoea

q3

be opened, thenasal septal flap described below needs to be elevated prior to removal of the anterior sphenoid wall). The middle turbinate is removed, which now allows access to theolfactory slit (region of thecribriform plate), andhence this area is now in continuity with the roof of the ethmoid air cells. 5 Oncetheexposure is complete, thedural defect is usually found with the aid of the operating microscope (200 mm lens). Again, a careful look for anything that

Fig. 35.6 Identifying posteriorly based septal mucosal flaps.

Procedure

1 The incision is extended through the skin, subcutaneous tissue and periosteum. Troublesome bleeding from the angular vessels can be dealt with using bipolar cautery. Two or three stay sutures, weighted with heavy haemostats, placed on each side of the incision act as effective retractors. 2 Periosteum is elevated, using a combination of sharp dissection, with the Freer’s elevator, and blunt dissection,withshortstrips of l c m ribbon gauze soaked intopicaladrenaline ( l:30000). The periosteum is mobilised to expose the nasal process of the maxilla, frontal bone and medial wall of the orbit. The lacrimal sac is displaced laterally without transecting the duct. 3 Dissection along the medial wall of the orbit continues to reveal theanteriorethmoidal vessels, which arecoagulatedwithbipolardiathermy and divided. The posterior ethmoidal vessels indicate the posterior limits of theethmoidair cells, and these aredealt with in a similar way. Lateral retraction of the orbital contentsduring this part of the dissection is best achieved by theassistant using acopper malleable retractor. 4 Theethmoidlabyrinth is entered by perforating the lamina papyracea just posterior to theposterior lacrimal crest, using a Tilley-Henkel forceps. The ethmoidal cells can be exenterated under direct vision via the incision and also with instruments inserted via the nose. The primary goal is to clean the mucosa away from the entire roof of the ethmoid sinus and to extend the explorationintothesphenoid sinus and region of the cribriform plateif necessary (if the sphenoidneeds to

Fig. 36.7 Posteriorly based septal mucosal flap-lateral view.

Fig. 35.8 Posteriorly based septal mucosal flap-coronal view.

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Chapter 35

pulsates is essential. Once identified, a posteriorly based septalmucosal flap is elevated (Figs 35.6-35.8). The superior incision extends along the anteroposterior dimension of the superior nasal septum at the junction of the septum and olfactory slit. This incision is carried as far anteriorly as possible (it is often necessary to remove most of the ascending process of the maxilla in this area to expose the anterosuperior nasal septum). The lower incision is approximately 2-2.5cm below, and parallel to, the superior incision (on elevating the flap, it invariably ‘shrinks’ and the author hasfoundthe classic description of a 1.5 cm-width flap inadequate). The anterior incision merely connects the anterior aspectof the superior and inferiormucosal incisions. A slightly longer flap can be obtained by extending the base of the flap on to the anterior face of the sphenoid (as is done when the leak is within the sphenoid). G A free piece of septalmucosaobtainedfromthe contralateral side is placed through the dural defect to stop the flow of CSF. It is best to push the plug through the fistula so that it acts as a one-way valve and is not simply flushed away by the flow ofCSF. Theseptal mucosal flap is then rotated into position over the defect and secured in place with the use of tissue glue. Over the flap is placed Lyostypt soaked in Sofradex topical antibiotic solutionandthe noseis packedwith l-inch (2.5cm) bismuth,iodoform and paraffinpaste (BIPP) impregnated ribbon gauze. Closure

The periosteal incision is closed with 4/0 catgut and 5/0 Prolene to skin. Chloramphenicol ointmentis applied to the incision. Postoperative management

Management of the lumbar drain in the postoperative period is asabove.Oncethedrain is clamped,the BIPP pack is removed if there is no recurrence of the CSF rhinorrhoea. The drain isremoved 24h after the removal of the nasal pack if no problems are encountered. Antibiotics are discontinued after removal of the lumbar drain and the patient is slowly mobilised. Complications

1 Incision-infection, paraesthesia and webbing of the wound may all result. 2 Haemorrhage-usually due to retraction of the ethmoidal vessels before adequate haemostasis is achieved.

3 Periorbital damage-epiphora and diplopia are usually transient. 4 Visual loss-unusualbutcan result if the globe is injured.

Endoscopic repair of CSF leak is a significant potentialcomplication of endoscopic ethmoidectomy, and immediate endoscopic repair of such leaks should be considered by any surgeon performing endoscopic nasal surgery if CSF rhinorrhoea isdiscovered intraoperatively. Other CSF leaks which are visible endoscopically are also amenable to endoscopic repair. Different techniques are described but all stress the importance of identifying the defect accurately. The mucosa is elevated from the surrounding bone and the free abdominal fat ormusculofascial graft is ‘tucked in’ above the bony skull base where possible, i.e. the intracranial side is supported.Mucoperiosteum (as a free graftfromthecontralateralnasalseptumor pedicled from the ipsilateral septum)is then placed over the defect and the edges are placed under the mucosal edges around the defect. Again, the use of tissue glue helps secure it, andfurthersupport is provided by the useof Gelfoam packing. Theapplication of endoscopictechniques to intranasalclosure ofCSF leakshasanumber of advantages over conventional methods. 1 Excellent field of vision, allowing exact localisationof the leak. 2 The ability to precisely clean mucosa from the bony defect without significantly increasing the sizeof the defect. 3 Accurate position of thegraftmaterial over the defect.

Alternatiwe procedures The nasal septal flap described above was popularised by Montgomery (197’3). However,other flaps have beendescribed for the repair ofCSF leaks, including theosteomucoperiosteal flap (Yessenow & McCabe, 1989), amiddleturbinate flap (Vrabec & Hallberg, 1964)and, where no septum or middle turbinate is available, a frontal pericranial flap introduced through a window createdby partial resection of the nasal bone (Pearson, 1991).

References Montgomery

WV

(19’73) Cerebrospinal

fluid

rhinorrhea.

Surgery for ~erebros~inal-~uid Rhinorrhoea Otolaryngol. Clin. North Am. 6, 757-71. Pearson BW (1991) Cerebrospinal fluid rhinorrhea. In: Paparella, Schumrick, Cluckman, Meyerhoff (eds) Otolaryngology, Vol. 111, Head and Neck. Philadelphia, WB Saunders, pp 1899-909. Vrabec DP & Hallberg OE (1964) Cerebrospinal fluid rhinorrhea.

255

Otolaryngol. Arch. 80, 218-29. Yessenow RS & McCabe BF (1989) The osteomucoperiosteal flap repair of cerebrospinal fluid rhinorrhea:a 20 year experience. Otolaryngol. Head Neck Surg. 101, 555-9.

Surgery JOHN K.S. ~O~

Introduction Epistaxis is an extremely common condition as well as a frequent otolaryngological emergency. It is estimated that up to 60% of people will experience one episode in their lifetime with 6% requiring medical attention (Shaw et al., 1993). In themajority of the cases the bleeding is idiopathic (Shaheen, 1987’). When a cause can be identified, epistaxis is usually secondary to nasal trauma, a local nasal pathology, a blood-vessel abnormality or a blood dyscrasia. Most epistaxes are mild and self-limiting; hospitalisation is only indicated for the severe cases. Even in these unusual cases, epistaxis can usually be controlled with anterior nasal packing. Posterior nasal packing is only occasionally required. Surgery is rarely necessary for epistaxis. Surgical treatment for epistaxis is controversial, with many options being available. The controversy relates more to the timing and nature of the surgical intervention than how to perform a particular operation. With the availability of modern endoscopes and accessory equipment, endoscopic techniques play animportant role in the managementof epistaxis (Bingham & Dingle, 1991; McGarry, 1991; Premachandra, 1991; O’LearyStickney et al., 1992).

Preoperative management Before surgery iseven considered, thepatientshould be adequately resuscitated. Attempts should be made to stop anteriornasal bleeding with an anterior nasal pack while, forposterior bleeding, balloontamponade is more effective. When balloon tamponade is used, the pressure should be adjusted to the minimum required to

arrest the bleeding. When nasal packs are used for more than 48h, it is advisable to give prophylactic antibiotics. Hypovolaemia should be prevented by adequate fluid replacement and, if necessary, with blood transfusion. Coagulopathy should be corrected and high blood pressure controlled. The majority of cases of, epistaxis will stop with adequate conservative treatment.

In general, surgical intervention is indicated in the following situations: 1 when there is continuous bleeding despite adequate conservative management; 2 whenthere is rebleeding whennasalpacksare removed; 3 when there is frequent and significant rebleeding.

The surgical management of epistaxis shouldbe tailored according to the cause whenever possible. Nowadays, using modern endoscopes and accessory equipment, the site of bleeding in most cases should be identifiable. Thus, when surgical intervention is considered necessary, surgical procedures can be logically considered in three steps. 1 Identification of the bleeding source. 2 Surgery for local control of bleeding. 3 Arterial ligation.

With modern endoscopes and the necessary accessories,

Surgery for Epistaxis the nose can be adequately examined even in the presence of active bleeding. Endoscopy for epistaxis differs slightly from diagnostic nasoendoscopy.

Endoscopy for epistaxis Preparation A full set of rigid endoscopes is required, including both 2.7mm and 4mm, with viewing angles of O", 30" and 70" for looking into narrow crevices and around corners. A flexible fibrescope with suction channel is a useful addition to bypass septal spurs and deflections. An efficient suction system is essential. A self-cleansing (irrigation andsuction) system withthe rigid endoscopes is useful accessory equipment. The procedure canbe performed under topical anaesthesia in most cases, using a long piece of ribbon gauze soaked in a solution of 4% xylocaine with 1:10 000 adrenaline. Small pledgets soaked in the same solution should also be available to pack narrow spaces as required. Torrential nasal bleeding is best managed under general anaesthesia.

Techniques The patient should be positioned supine, with the head raised, neck slightly extended, well supportedand turned towards the surgeon. Patients with epistaxis coming to surgery will almost always have a nasal pack inside their nose. Starting with the4mrn 0" endoscope, thenasal pack is slowly removed while taking care to note any sites of bleeding. Although the nasal mucosa is not topically prepared, there is usually enoughroomforthe passage of the endoscope immediately after the nasal pack is removed. Nasal secretions and blood clots are cleared with suction. No attempt should be ,made for a detailed endoscopic examination at this stage as thenasal mucosa will swell quickly and bleeding may recur at any time. The nasal mucosa should then be prepared using a single, long, narrow ribbon gauze. A singlepiece of ribbon gauze is preferred as it can be used to exert pressure on the bleeding pointsmore effectively than multiple smaller pieces. Layered nasal packing is applied, starting from the roof towards the floor. This will facilitate the subsequent endoscopy as the gauze is removed in the reverse order. Adequate time (10-15 min)should be allowed for mucosal anaesthesia and vasoconstriction to be achieved. As the nasal pack is removed great care should be taken to note any signs of bleeding, septal abnormality or varicose vessels at the posterior part of the nasal septum and the choana.

q7

If there is no bleeding after the nasal pack is removed, a gentle diagnostic nasoendoscopy shouldbe performed without reinsertion of a nasal pack. If epistaxis recurs at sites that can be localised, the pledgets should be accurately applied to these sites. The surgeon then prepares for local control of the bleeding. Surgery for local control of bleeding

In addition todiagnostic instrumentation, the following equipment should be available. 1 Bipolar diathermy (forceps and malleable pencils). 2 Monopolar suction diathermy. 3 A septoplasty set with a 2mm chisel.

Bleeding within the nasal fossa If bleeding continues after removal of the nasal pack and the source can be identified, this is controlled by simple means such asdiathermy. Whenever possible, bipolar diathermy should be used as it is more precise. The most useful instrument is the malleable bipolar diathermy pencil, which allows the surgeon to reach almostany bleeding pointwithinthenasal fossa. If the bleeding is profuse, monopolar suction diathermy provides suction and diathermy simultaneously. When bleeding is heavy, it may be stopped or slowed temporarily by injecting a small amount of xylocaine with adrenalinethroughadental syringe. Diathermy may then be applied.This technique works well on the septum.

Bleeding from behind a septal abnormality Any anatomicalabnormality identified on endoscopy preventing adequate control of the epistaxis should be dealt with immediately. These include septal deflections and spurs. Septal spurs can be corrected under local anaesthesia. The mucosa around the spur is injected subperichondrially/subperiosteally using 2% xylocaine with 1:80 000 adrenaline. Injection in the correct plane will result in immediate blanching of the overlying mucosa. A small incision is made using a Freer elevator parallel to the length of thespur.Mucosal flaps are raised on either side of the incision until the whole spur is laid open on either side by about 1mm. The spur is removed by means of a small chisel. The mucosal flaps are repositioned without suture at the endof the procedure (Fig. 36.1). If there is no oozing, no nasal pack is required. Otherwisea loose pack should be secured overnight.

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Chapter 36 3 there is recurrent severe epistaxis (especially when associated with hereditary telangiectasia). Contraindications

In general, surgical intervention is contraindicated in the following situations: 1 there is significant associated injury (especially head injury ); 2 there is a blood dyscrasia; 3 epistaxis recurs after previous arterial ligation (embolisation may be more useful). Principle of arterial ligation Fig. 36.1 Removal of a septal spur.

Bleeding from the back of the nasal septum or the nasopharynx

Posterior bleeding may be difficult to reach and in these cases the techniques described in ‘combined-approach nasopharyngoscopy’ may be employed. The endoscope is passed from the front, providing a visual guide, while the diathermy forceps or pencils are passed retrograde through the mouth. Nasal packing

If bleeding is profuse after removal of nasal packing prior to nasoendoscopy, then it is wise to place a loose nasal pack at the end of the definitive procedure. When bleeding is not controlled by the simple local measures described above,the nose should be repacked firmly witha bismuth, iodoformand paraffin paste (BIPP) pack. A plan should then be made for further appropriate intervention, including possible arterial ligation. If bleeding was secured with an anterior nasal pack alone, further intervention wouldbe planned at a later stage. If bleeding was not securely controlled or postnasal packing wasrequired, immediate arterialligation may be necessary. Arterial ligation Indications

Arterial ligation, although notcause-specific, is an effective means of epistaxis controland should be considered in the following circumstances: 1 rapid control of epistaxis is critical; 2 other methods to control the bleeding have failed;

The aim of arterial ligation for the controlof epistaxis is to lower the perfusionpressure so that bleeding will stop or may be stopped more easily by local measures. In general, themoredistalthe site of ligation themore effective theprocedure,asthe development of anastomotic channels will be less likely.

Relevant anatomy Blood supply of the nose

The nose is an extremely vascular structure, being supplied by branches from both the internal (ICA) and the external carotid arteries (ECA). The main blood supply is derived from the maxillary artery, which is the larger terminal branch of the external carotid. This is supplemented by the superior labial branchof the facial artery. The nose also derives some of its blood supply from the internal carotid system through the ethmoidal branches of the ophthalmic artery. Thebloodsupply of thelateralnasal wall can be described in quadrants made by vertical and horizontal lines passing through its centre(Last, 1978). The posterosuperior quadrant is supplied by ascending branches of thesphenopalatineartery.Theposteroinferior quadrant is supplied by branches fromthe greaterpalatineartery.Theanterosuperior quadrant is supplied by theanteriorandposteriorethmoidal arteries. Theanteroinferior quadrant is supplied by branches from thefacial artery and perforating branches of the greater palatine artery. Whereas the lateral nasal wall is supplied by quadrants, the septum is supplied in halves (Fig. 36.2) (Last, 1978). The anterosuperior half is supplied by the anterior ethmoidal artery assisted by branches from thefacial artery. The posteroinferior portion of theseptum is supplied by branches fromthe sphenopalatine artery.

Surgery for Epistaxis

259

the bleeding is profuse and the source is poorly localised, a combination of arteries from both systems may need to be ligated (Hassard et al., 1986; Singh, 1992). The external carotid system

The external carotid system can be approached either by ligating the ECA in the neck close to its origin or by ligating the maxillary artery in thepterygopalatine fossa. The former approach has the advantage of being a simple procedure. The latter, although slightly more technically demanding, has the advantageof being more specific and achieves a better result (Spafford & Durham, 1992).

Ligation of the external carotid artery

Fig. 36.2 (a) Blood supply to the lateral wall of the nose. (b) Blood supply to the nasal septum.

The procedure can be performed under either general anaesthesia or local anaesthesia. The patient should be positioned supinewithshouldersupport and head raised. The neck should be slightly extended and turned to the opposite side. The incision is placed along a skin crease at the upper border of the thyroid lamina. Thisis continued through the platysma muscle and skin flaps are raised in the subplatysmal plane. The deep cervical fascia is then opened parallel to the anterior border of the sternomastoid muscle. The greater auricular nerve may be encountered and should be preserved. The carotidsheath is then identified by blunt dissection between the Sternomastoid muscle and theinfrahyoid muscles. The carotid pulsation is easily palpable. At its origin, the ECAis deep to theinternalcarotid.The external carotid is identified by demonstrating its branches. It is then doubly ligated, in continuity, with Osilk distal to its lingual branch (Fig. 36.3).In tracing the branches of the external carotid, the surgeon should be aware of the hypoglossal nerve, which may cross the surgical field. The deep cervical fascia is loosely approximated to the sternomastoid muscle. The wound is then closed in two layers.

Choice of arterial ligation

The decision to ligate an individual artery or a combination of arteries will depend on whether the site of bleeding is identified or not. A clear understanding of the principle of arterial ligation and the blood supply of the nose is necessary. When the bleeding is from the roof of the nose, theethmoidalarteries should be dealtwith first. On the other hand, when the bleeding is from the lower part of the nasal fossa or the lateral wall of the nose, the maxillary or the ECA should be ligated. When

Ligation of the maxillary artery The nose derives most of its blood supply from the ECA through its maxillary branch. Ligation of the maxillary artery is preferred to the external carotid in most instances of epistaxis, except in the critically ill patient, when the simplest procedure is indicated. The tributar-

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Chapter 36

Fig. 36.3 Ligation o f the external carotid artery.

iesof themaxillaryartery to the nose begin inthe pterygopalatine fossa. This is the ideal site to ligate the maxillary artery and its branches to the nose. The operation is preferably performed under hypotensive general anaesthesia. The patient is positioned supine with the head of the operating table raised. The patient’s neck is slightly extended and rotated towards the surgeon. The microscope, using a 300mm focallength lens, should stand at the top end of the table so that it is easily available even for bilateral ligation. The initial steps arethe same asfor Caldwell-Luc operation, except that theanteriorantralwindow should be enlarged until the whole of the posterior wall can be visualised through the microscope. The posterior wall of the antrum is palpated with a suitablebluntinstrument, such asa Freer’s elevator, to identify thethinportionfromthe thicker medial buttress. The mucosa is then removed over the posterior wall. The thickness of bone making up the posterior antral wall varies between individuals. When it is thin, theposteriorantral wall crackswith gentle pressure using a Freer’s elevator. Whenit is thick, alot of time can be saved by thinning the bone with a burr. The microscope should now be set into position. The cracked posterior bony wall is then removed piecemeal untilthe periosteal layer is exposed. Any prominent veins arecoagulated before the periosteal layer is opened to gain access into the pterygopalatine fossa. After the periosteum of the posterior antral wall has been opened, the main trunk of the maxillary artery is exposed by blunt dissection. This is achieved by the

repeated opening action of a pair of round-ended scissors into the glistening fat of the pterygopalatine fossa. The pulsation of the artery will be evident. After the main trunk of the maxillary artery is identified, it should be held taut withablunthook.This will facilitate cleaning of the rest of the artery and its main branches. No attempt should be made to clip the artery until all the branches of the maxillary trunk have been identified. The maxillary trunk and its branches have the configuration of an H inthepterygopalatine fossa (Fig. 36.4). The haemostatic clips should be applied firmly and doubly if possible, as shown. As the main trunk of the maxillary arterycomes from a deeper aspect than its branches, it canoccasionally be missed. The infraorbital branch may be mistaken forthe main trunk of the maxillary artery. Whenthehaemostatic clips are correctly applied, arterial ligation in continuity will suffice for most instances of acute bleeding. However, if the procedure is performed for hereditary telangiectasia, the maxillary artery should be divided and any aberrantvessels should be clipped or coagulated with bipolar diathermy. The buccal incision is closed loosely with interrupted catgut to lessen the postoperative facial oedema. There is no need for nasal antrostomy. Complicationsare similar to thosefrom CaldwellLuc operation. Isolated cases of total ophthalmoplegia have been reported in the literature (Beall et al., 1985).

>

The internal carotid system

The internal carotid system contributes much less to the nasal blood supply than the external carotid. The anterior and posterior ethmoidal arteries, both being derived from the ophthalmic artery, areconveniently reached in the orbit. The anterior ethmoidal artery is the larger of the two andcontributes more to the blood supplyof the nose. In many instances, only the anteriorethmoidal artery requires ligation.

Ligation of the ethmoidal arteries The operation is performed under general anaesthesia again, preferably using hypotensive techniques. The eye should be carefully protected by tapes or a temporary tarsorrhaphy.The skin preparationsolution must be non-irritant to the eye. A curved incision about 2cm in length is placed approximately midway between the dorsum of the nose and the medial canthus, as shown (Fig. 36.5).The incision should be marked accurately on the skin and the lacrimal apparatus shouldbe identified by palpation and avoided. The area should be injected with 1:200000 adrenaline 5-1Omin before the incision is made to minimise bleeding from the wound.

Fig. 36.5 Ligation of the ethmoidal arteries.

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261

The incision is continueduntilthe nasal bone is reached. The periosteum is raised in one layer with the skin. The periosteal flap is raised progressively into the orbit, displacing the orbital periosteum and the lacrimal sac laterally. Care should also be taken when raising the periosteum not to damage the trochlea, which would result in mechanical dysfunction of the superior oblique muscle (Couch et al., 1990). Theethmoidal vessels perforatethe medial orbital wall into the anterior and posterior ethmoidal canals respectively, at or close to the frontoethmoidal suture (Fig. 36.5). The anterior ethmoidal artery will be encountered at distance a about 1.5-2cm fromthe lacrimal fossa. It will appear as a cord-like structure. After it has been cleaned circumferentially, haemostatic clips should be firmly and doubly applied. If only the anterior ethmoidal artery is to be ligated, the clips are preferably left in coutinuity with the vessel. If the posterior ethmoidal artery is also to be ligated, the anterior ethmoidalartery requires dividing between the clips. Theorbitalperiosteum is similarly raised and the posterior ethmoidal artery will be encountered about 0.5-1cm further back. It is clipped similarly but it is not necessary that it is divided. Occasionally it may be difficult to clip the posterior ethmoidal artery because the field becomes either too narrow or too close

to theoptic nerve. In these instances theposterior ethmoidal artery can be simply coagulated with bipolar diathermy. Theanteriorethmoidalarterycan be absent in as manyas 14% of cadaver dissections unilaterally and 2.5% bilaterally (Shaheen, 1967). This is especially important to bear in mind if both the anterior and the posterior ethmoidal arteries areto be clipped. The optic nerve may then be mistaken as the posterior ethmoidal artery and clipped, resulting in blindness. Post-arterial ligation nasal endoscopy

At the end of any arterial ligation procedure for control of epistaxis, the nose should be examined for two reasons, The effect of ligation can be assessed immediately as successful ligation should leave thenasal mucosa blanched. If there is any residual bleeding, it should be significantly slowed. Thiscould be the ideal time for achieving local control. If the nasal mucosa appears blanched andwithout bleeding, onlya loose pack should be applied. If there is still significant bleeding, an arterial branch might have been missed or an additional artery may require ligation.

Epistaxis from haemorrhagic Epistaxis requiring surgery in most patients arises from arterial bleeding. However, in the case of hereditary haemorrhagic telangiectasia, epistaxis is due toboth arterial and capillary bleeding. Results of any form of therapy, including arterial ligation, are poor (Rebeiz et al., 1995).These patients usually require a combination of arterial ligation (or embolisation) and local control. It is important to cause as little mucosal damage as possible as there is always need for repeated local therapy. A number of lasers have proved useful in the management of thiscondition (Kluger et al., 1987; Illum & Bjerring, 1988; Haye & Austad, 1991).

Conclusion Epistaxis is acommon ENT emergency and may at times be life-threatening. Successful management depends upon an understanding of the condition and the ability to apply the techniques for epistaxis control in a logical manner.

Beall J, Scholl P & Jafek B (1985) Totalophthalmoplegia after internal maxillary artery ligation. Arch. Otolaryngol. 111 (lo), 696-8. Bingham B & Dingle AF (1991) Endoscopic management of severe epistaxis. J.Otolarngol. 20 (6), 442-3. Brucher J (1969) Origin of the ophthalmic artery from the middle meningeal artery. Radiology 93 (l), 51-2, Couch JM, Somers ME & Gonzalez C (1990)Superior oblique muscle dysfunction following anterior ethmoidal artery ligation for epistaxis. Arch. O p ~ t h a l ~ 108 o ~ .(8), 1110-13. Hassard AD, Kirkpatrick DA & Wong FS (1986) Ligation of the external carotid and anterior ethmoidal arteries for severe or unusual epistaxis resulting from facial fractures. Can. J.Surg. 29 (6), 447-9, Haye R & Austad J (1991) Hereditary hemorrhagic teleangiectasia-argon laser. Rhinology 9 (l), 5-9. Hiura A (1980) An anomalousophthalmicarteryarsingfromthe middle meningeal artery. Anat. Anx. 147 ( S ) , 473-6. Illum P & Bjerring P (1988) Hereditary hemorrhagic telangiectasia treated by laser surgery. Rhinology 26 ( I ),19-24. Kluger PB, Shapshay SM, Hybels RL & Bohigian RK (1987) Neodymium-YAG laser intranasal photocoagulation in hereditary hemorrhagic telangiectasia: an update report. Laryngoscope 97 (12), 1397-401. Last RJ (1978) TheNose. Section 6, Anatomy Regional and Applied, 6th edn. Edinburgh, Churchill Livingstone. McGarry GW (1991) Nasal endoscope in posterior epistaxis: a preliminary evaluation. J.Laryngol. Otol. 105 (6),428-31. NakagawaT,Tanabe S & Sato 0 (1982) Anomalous ophthalmic artery-case reports and review of literature. N o To Shinkei 34 (4), 40.5-13. O’Leary-Stickney K, Makielski K & Weymuller EA, Jr (1992) Rigid endoscopy for thecontrol of epistaxis. Arch. Otolaryngol. Head Neck Surg. 118 (9), 966-7. Premachandra DJ (1991) Management of posterior epistaxis with the use of the fibreoptic nasolaryngoscope. J. Laryngol. Otol. 105 (l), 17-19. Rebeiz EE, Bryan DJ, Ehrlichman RJ & Shapshay SM (1995) Surgical management of life-threatening epistaxis in Osler-Weber-Rendu disease. Anu. Plast. Surg. 35 (2), 208-13. Shaheen O H (1967) Thesis for the Master of Surgery, University of London. Shaheen O H (1987) Epistaxis. In: Kerr AG (ed.) Scott-B~own’s Otolaryngology, Vol. 4. Rhinology, 5th edn. Butterworth International Editions. Shaw CB, Wax MK & Wetrnore SJ (1993)Epistaxis: a comparison of treatment. Otolaryngol. Head Neck Surg. 109, 60-5. Singh B (1992) Combined internal maxillary and anterior ethmoidal arterial occlusion: the treatment of choice in intractable epistaxis. J.Laryngol. Otol. 106 (6), 507-10. Spafford P & Durham JS (1992) Epistaxis: efficacy of arterial ligation and long-term outcome. J.Otolaryngol. 21 (4), 252-6.

Endoscopy

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Nasopharyn JOHN K.S. WOO

Introduction The nasopharynx is functionally part of the nose, although developmentally itis part of the pharynx. Notoriously difficult to visualise, the nasopharynx is frequently neglected when the nose and the throat are being examined. Pathology in the nasopharynx is central to many common ear, nose and throat disorders. Advances in modern endoscopic equipment allow this key anatomical region to be examined easily and thoroughly.

Surgical anatomy of the nasopharynx The nasopharynx is the part of the pharynx that lies behind the nose (Fig. 37.1).Its size isapproximately that of the terminalsegment of the thumbof its owner (Last, 1978). Anteriorly it opens into the nasal cavities while inferiorly continues it into the oropharynx. The Eustachian cushions project from its lateral walls, each in the shape of an inverted J. The long limb of the J extends posteromedially and continues inferiorly as the salpingopharyngealfold. The lateral recess (fossa of Rosenmuller) is the slit-like space, oneon each side, posterior and lateral to the long limb of the Eustachian tubal orifice. The internal carotid artery (ICA)is closely related to the fossa of Rosenmiiller; The skull base lies posterosuperiorly to the margin of the nasopharynx.

Indications for nasopharyngoscopy Thenasopharynxcannow be viewed withminimal discomfort to the patient and it shouldbe a routine part of every clinical examination of the ear,nose and throat.

Nasopharyngoscopy may also be a necessary part of another endoscopic procedure, such as flexible laryngoscopy and laryngobronchoscopy. It is also performed for therapeutic reasons, such as removal of a polyp or a foreign body, or laser therapy for a lesion in the nasopharynx.

Indirect The nasopharynx can also be examined with a postnasal mirror.Thisimportanttechniqueshouldnot be neglected as the nasopharynx can be clearly visualised in up to 70% of patients. The tongue is depressed slightly with a right-angled tongue depressor. The patientis then instructed to hold hislher breathtemporarily orto breathe through the nose. In this way, the soft palate will relax andthevelopharyngeal inlet will open for inspection. A postnasal mirror with an adjustable mirror head is requiredfor visualisation of the different parts of the nasopharynx.

Thenasopharynxcan be visualised eitherantegrade through the nose or retrograde via the oropharynx, and occasionally a combined approach is employed (Woo et al., 1990, 1991). Antegrade naso~hary

Antegrade nasopharyngoscopy can be performed using either a flexible fibrescope or a rigid Hopkins rod lens. There are advantages and disadvantages with either instrument. The flexibility of the fibrescope allows it to

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Anatomic boundaries

Fig. 37.1 Anatomy of the nasopharynx in relation to the lateral nasal wall.

bend around a septal spur and yet maintain an end-on view. The suction channel incorporated with some instruments allows aspiration during the procedure, thus maintaining a clear view. The flexible instrument has a longer working length so that a more comfortable distance exists between the doctor and the patient. The rigid Hopkin’s rod lens can be controlled with just onehand, freeing theotherhandforadditional instrumentation.Illumination is bright and it hasa wide-angled view and provides excellent optics. These characteristics offer a better-quality picture for still photography and video documentation. The transnasal view through a 0” endoscope is represented diagrammatically in Fig. 37.2. Theprocedure is best performedwiththepatient lying comfortably on a reclining chairwiththehead turned slightly towards the surgeon. The right-handed surgeon should sit on the patient’s right side with an adjustable stool. The examination position is adjusted so that the surgeon’s eyes are level’with the patient’s nose. It is necessary to anaesthetise and vasoconstrict the nasal mucosa for ease of the procedure and comfort of the patient. This can be achieved by applying ribbon gauze soaked with a5% cocaine solution. In institutions where cocaine is not easily available for medical use, a solution made up of four parts of 4% xylocaine with one part of 1:10000 adrenaline is suitable. Excess solution should be squeezed from the ribbon gauze before

Fig. 37.2 Endoscopic view of the nasopharynx through a 0” rigid endoscope.

insertion into the nose. The gauze should be carefully placed against the middle and inferior turbinates. For patients withvery swollen turbinates, the positionof the medicated gauze should be readjusted and pushed further inside the nose. After about 10min, the patient will be ready for the procedure.

~ ~ s o p ~ ~ ~ y n g o s 267 copy

Fig. 37.3 Endoscopic view of the nasopharynx through a 90" rigid endoscope.

The endoscope should be held in the surgeon's right hand. The other hand should adopt a position so that the fingers can steady the tip of the endoscope. This is particularly important when using the flexible endoscope. The tip of the endoscope shouldbe carefully introduced into the nostril under direct vision. The surgeon should immediately view throughthe eyepiece once the endoscope is inside the nose. The endoscope is advanced along the floor of the nose. Once the nasopharynx is reached, the patient is instructed to phonate 'ng' and 'ah' and asked to swallow. With these manoeuvres, the soft palate may be observed in a relaxed, tightened and dynamic state. Thismay expose an abnormality that might otherwise be overlooked. The flexible endoscope should be able to bypass most anatomical obstacles. When rigid endoscopes are being used, a brief inspection of the nasal fossae should be done first. The wider side of the nose should be used for the passage of the endoscope. The surgeon may, very rarely, find it difficult to advance the endoscope without causing some discomfort to thepatient. Under these circumstances, the other side of the nose should be tried or the flexible instrument be used instead. Retrograde nasopha

Here the nasopharynx is viewed from the oropharynx through a side-viewing rigid endoscope. This method is not suitable for patients with a narrow velopharyngeal inlet or patients with a long, redundant soft palate.

The patient should be seated and leaning slightly forward. In this way, gravity will tend to openthe velopharyngeal inlet. The back and neck should be well supported so that thepatientcannotretreatasthe endoscope advances. The surgeon should sit facing the patient with his eyes level with the patient's throat. No anaesthesia is necessary unless this is attempted in patients with a sensitive gag reflex. Under these circumstances, the throat can be anaesthetised using a 10% xylocaine spray. Suitable viewing angles range from 70" to 120", with the 90" lateral viewing endoscope being ideal as this angle is most versatile and suits the majorityof patients. Thepatient is asked to open hislher mouthwithout protruding the tongue. The endoscope is advanced under direct vision as the tongue is depressed lightly. The surgeon should only look through the endoscope after the tip of the endoscope has passed the uvula. A panoramic view of the nasopharynx is obtained by slightly rotating the endoscope along its axis (Fig. 3'7.3). The soft palate should be relaxed during the examination; this can be achieved by asking the patient to breathe through the nose or to temporarily hold hislher breath. haryngoscopy

In special situations the antegradeand retrograde routes are combined. This should be undertaken with general anaesthesia for the patient's comfort and safety. Nasopharyngoscopy under general anaesthesia is necessary when it is likely to cause a lot of bleeding andlor pain. The nasal mucosa should be prepared topically as described previously. The patient is placed in the supine position and intubatedtransorally with an endotracheal tube (ET).A Boyle-Davis or similar mouth gag is set in position. A suction catheter is passed through each nostril and brought out through the mouth. The soft palate is lifted forward by gently tightening the ends of the catheters (Fig. 3'7.4). Thenasopharynx is now easily viewed withthe endoscopes. Instrumentationcan be introduced simultaneously via the nose or mouth. In places wherenasopharyngealcarcinoma is endemic, it may be necessary to take deep biopsies from the fossa of Rosenmiiller under direct vision to confirm or exclude a submucosal tumour.In these circumstances a Yankauer speculum in combination with a headlight may be used to gain access. The Yankauer speculum is introducedthroughtheopenmouth, lifting the soft palateforward so that the beak of the speculum is placed behind the Eustachian cushion. In this way, the depth of the fossa of Rosenmiiller is opened while the Eustachian cushion is pushed laterally to avoid injury.

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Video-assisted nasopharyngoscopy During both antegrade and retrograde nasopharyngoscopy, the endoscope can be coupled with a video camera and theprocedure recorded and viewed on a television screen. This allows the endoscopic technique to be documented and taught simultaneously.

Complications of nasopharyngoscopy Complications associated with nasopharyngoscopy are rare. However, during passage of the endoscope, injury to the nose, throat or Eustachian tube may result if the procedure is not carefully performed. Even following deep biopsy, haemorrhage requiring transfusion is rare.

References

Fig. 37.4 Set-up for combined-approach nasopharyngoscopy.

Last RJ (1978) Tbe Nose. Section 6, Anatomy Regional and Applied, 6th edn. Edinburgh, Churchill Livingstone. Woo JKS & Sham CL (1990) Diagnosis of nasopharyngeal carcinoma. Ear Nose Throat J.69 (4), 241-52. Woo JKS & Waldron J (1991) Diagnosis. In: van Hasselt CA & Gibb AG (eds) Nasopbary~gealCarcinoma. Hong Kong, Chinese University Press, pp. 93-104.

Pharyngolaryngosco Rigid Oesophagosco (including Panendo SIMON A. HICKEY Pharyngolaryngoscopy Indications

Direct pharyngolaryngoscopy is indicated for the controlled and detailed examination of the pharynx and larynx and should be combined with palpation of the so-called ‘silent areas’ of the pharynx, i.e. the tongue base, postnasal space, tonsil fossae and, where accessible, pyriform fossae. It is indicated for: 1 The assessment and biopsy of lesions of the pharynx and larynx and the removal of foreign bodies therefrom. 2 Guidance during difficult intubations, the passage of a rigid bronchoscope, especially in children. 3 The identification of theoesophageal inlet forthe passage of a nasogastric feeding tube. A sliding or openbacked laryngoscope is used so that the endoscope can beremoved without removing thebronchoscope or feeding tube. 4 Direct pharyngolaryngoscopy is used to identify the opening of a pharyngeal pouch prior to packing or for placing a fibre light in order to facilitate the identification of the pouch in the neck. 5 It may also beused to directtheplacement of a stomach tube, for guidance during upper oesophageal myotomy and to provide access for the endoscopicdivision of the common wall of the pouch and pharynx in the Dohlmann’s procedure. Preoperative management

Instability of the cervical spine may occur with rheumatoidarthritis or spinaltrauma.Carefulpreoperative assessment, including flexionlextension X-rays of the cervical spine, is essential in such patients. Fibre-optic examination may be substituted where there is a risk of

cervical injuryfrommanipulationunderanaesthesia, although the examination will generally beless complete. Loose, capped or protuberant teeth are at risk duringpharyngolaryngoscopy and rigid oesophagoscopy. The patient shouldbe advised of this. The patient with an obstructingtumourshouldalso be advised that tracheostomy or prolongedintubation maybe necessary should postoperative swelling increase airway obstruction. Careful communication with the anaesthetistis essential in order that a decision can be made whether to intubate or not, the type of tube to be used, whether spontaneous, intermittent positive-pressure or jet ventilation is to be used and hence the type of muscle relaxant to be used. As directpharyngolaryngoscopyand rigid oesophagoscopycan result in profound vagal stimulation and dysrythmias, a careful cardiorespiratory history and examination are required preoperatively. Relevant anatomy As pharyngolaryngoscopyand

rigid oesophagoscopy require the passage of a straight instrument, it is essential that the operatorshould understand the movements of the cervical spine necessary to align the oral, pharyngeal and laryngeal inlets alongthesameaxisfor pharyngolaryngoscopy (extension of the atlantooccipitaljointcombinedwith neck flexion) and that these are different from those required to align the oral, pharyngeal and oesophageal inlets for rigid oesophagoscopy (extensionof both the atlanto-occipital joint and the neck). Careful preoperative examination may identify factors which may make it difficult to achieve such alignment, e.g. cervical lordosis, restricted neck movements,

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retrognathia, a bulky tongue base and protuberant upper dentition. These factors, especially in conjunction with poor relaxation or inadequate depth of anaesthesia, may make direct pharyngolaryngoscopy difficult or even impossible. The oesophagus runs from the cricopharyngeal sphincter to the oesophageal hiatus in the diaphragm and cardia of the stomach. Endoscopically the cricopharyngeal inlet lies, on average, 15cm from the anterior incisors. The indentation of the oesophagus by the aortic arch, as it crosses from anterior to lateral on the left side, lies at a distance of 25cm and the gastrooesophageal junction at approximately 40 cm from the anterior incisors. During its course, the axis of the oesophagus initially runs in the midline, but once the halfway point is reached it tends to curve anteriorly and slightly to the left. In order to pass a rigid oesophagoscope, it is therefore essential to align the oral and oesophageal inlet along the same axis (vide supra). Where access is made difficult by retrognathia, tongue bulk and protuberant upper dentition, it is possible to insert the oesophagoscope off-centre and compensate for this by some rotation of the head in order to realign the axis of the oral inlet with- the oesophagealinlet. Operative technique

Preparation

Anaesthesia Apreoperative drying agent, e.g. hyoscine, greatly facilitates the examination, by reducing secretions and preventing dangerous vagal bradycardia. Direct pharyngolaryngoscopy is possible under local anaesthesia and sedation,butmost prefer to use general anaesthesia. After induction, anaesthesia is maintained with a face mask. The pharynx and larynx are sprayed with local anaesthetic (LA) to reduce vagal stimulation and the risk of postoperative laryngospasm, and muscle relaxants are given to facilitate passage of the endoscopes. The examination may be carried out rapidly during a short apnoeic period, but preferably more slowly, while ventilatory support is achieved with intermittent positive-pressure ventilation or jet ventilation via a parallel endotrachealtube (ET)or cannula. In order to minimise the dose of anaesthetic gas inhaled by the operator, methods employing the spontaneous respiration of anaesthetic gases delivered to the pharynx should be avoided. Where a jet ventilator is used, care should be taken to ensure that an exit port for entrained gases is always

available, as there is a risk of pneumothorax.The Venturi injector should not be used for very small babies, for this reason.

Prophylactic antibioticslsteroid cover Prophylactic antibiotics are unnecessary in the absence of intercurrent valvular heart disease. The same is true of steroid cover, apart from exceptional circumstances, i.e. preceding steroid therapy or where there is likely to be instrumentation, lasering or intubation of an already critically narrowed airway.

Patient positioning The patient should be placed supine with theneck flexed and the head extended, so as to align the axis of the larynx with the mouth in the ‘sniffing the morning air’ position. Thismay be achieved by extending thehead on a flat table, with neck flexion occurring passively as a result (Kleinsasser, 1992) (Fig. 38.1). The position may be maintained by steadying the head with the left hand, placing the index finger in the mouth against the palatal surface of the front teeth and applying a gentle rotatory pressure to extend the head (some operators prefer to stabilise the head with a small neck roll or pillow to maintain the cervical lordosis). With theleft hand in this position,the left thumb can be used to support and control advancement of the scope and to protect the upper teeth from damage caused by inadvertent use of the teeth as a fulcrum to rotate the scope (Fig. 38.2). If an ET is passed, it should be positioned to lie to the left foraright-handed surgeon and vice versa for a lefthanded surgeon. Procedure

The operator is seated at the head of the table. A tooth guard is inserted to protect the upper teeth.If the patient has no upper front teeth, a gauze swab is used to protect the gingivae. Holding the scope in the right hand, the tip of the laryngoscope is passed between the teethand over the back of the tongue in the midline until the uvula is reached, progress being observed at all times by direct vision throughthe scope. The scope is then directed laterally to inspect the tonsillar fossae and faucial pillars. Aspiration of saliva may be necessary. The scope is then advanced, using the thumb of the left hand in conjunction with the right hand to control the movement. At this stage the tongue base protrudes into the axis of examination and needs to be elevated and compressed anteriorly, by lifting the scope towards

Pha~yngola~yngos~opyand RigidOesophagoscopy

271

Fig. 38.1 (a) ‘Sniffing the morning air’ position for pharyngolaryngoscopy, with alignment of the oral, pharyngeal and laryngeal axes. The dark arrow shows the correct direction of scope elevation for compression of the tongue base (redrawn after Kleinsasser, 1992). (b)Manoeuvre to achieve head extension with simultaneous neck flexion. This position may be maintained with the left hand (as in Fig. 38.2) or with a small ‘neck-roll’ pillow (redrawn after Kleinsasser, 1992).

Fig. 38.2 Positioning of left hand for pharyngolaryngoscopy and rigid oesophagoscopy.

the ceiling and by minor rotatory movements as the tip of the scope is advanced. The tongue base, valleculae and pyriform fossae are examined sequentially, distending these areas with the tip of the scope to allow adequate inspection. The examination of the hypopharynx and upperoesophageal lumen requires the use of a longer pharyngoscope or oesophagoscope. The laryngeal inlet is examined next. The tip of the

scope is passed behind the epiglottis and its laryngeal surface inspected. It may be necessary to displace the ET posteriorly at this stage in order to view the anterior larynx. Similarly thetube may need to be displaced anteriorly to view theposterior commissure. Despite careful patient positioning, it may not be possible to view the anterior commissure of the larynx. Use of the narrower-profiled ‘anterior commissure scope’ may improve the view, as may the application of pressure to the subglottictrachea.Theapplication of a suspending laryngostat often produces furtherelevation of the tipof the scope and improves the view. Examination may be impeded by retrognathia and protuberant upper dentition. Access may be improved by passing the scope through the teeth ‘off-centre’, i.e. between the molar teeth. This has the disadvantagethat usually only one side of the larynx and pharynx can be examined and the scope has to be reintroduced to examine the opposite side. Examination of the laryngeal ventricle is greatly assisted by the application of a laryngostat, in that the operatoris able to use two hands and can displace the false cord with a ”biopsyforcep or laryngeal hook and use a wide-angle 70’ Hopkin’s rod nasal endoscope to view the ventricle. Thesubglottis may be examined using a similar scope. Where a laryngeal lesion is identified, inspection ofxand surgery to the

larynx is greatly facilitated by the use of an operating microscope with a 400mm focal-length lens (see Microlaryngoscopy -Chapter 45). It is recommended that a full examination is performed as atraumatically as possible before taking a biopsy or making an incision, as the introduction of blood into the field greatly reduces observer accuracy. Excessive bleeding may be controlled by the application of a cotton pledget soaked in topical adrenalinesolution (1:1000) andsupported on a carrier. Alternatively a suction diathermy probe may be used. Postoperative management

Once the patient is awake and thus able to protect the airway, he/she is able to resume normal activities. The patient may experience some soreness and occasionally mild analgesics may be required. Complications

Occasionally laryngeal swelling will cause significant airwayobstruction.Thisshould be treatedwitha graded regimen according to severity, using humidification, nebulised racemic adrenaline, steroids, helium and oxygen. If worsening stridor, dyspnoea or desaturation occurs, thenreintubation or tracheostomy may be required. Careless technique may cause bruising or laceration of the lip. Suturing is rarely necessary. Occasionally a tooth will be chipped, broken or knocked out during introduction of the scope. A careful search for thetooth fragmentshould be made, including bronchoscopy if indicated. Laceration of the pharynx is uncommon and can usually be treated conservatively. Perforation is uncommon, except in cases of undiagnosed pharyngeal pouch or impingement on prominent a cervical osteophyte. Gentle technique should avoid such a disaster, but when it occurs the perforation should be explored and repaired. Alternative procedures

Although fibre-optic endoscopy has its advocates (Thomson & Batch, 1989), it is considered by many to be inferior to rigid endoscopic examination of the hypopharynx and upper oesophagus, as it does not allow easy distension of the area. This impedes anatomicalorientationduringtheexamination and hence impedes the assessment and staging of malignant disease. Direct observation makes obscuration by blood and saliva much less likely.The removal of large foreign

bodies is likely to be far less traumatic when the field is distended and theforeign body disimpacted under direct vision.

Rigid oesophagoscopy indications

Rigid oesophagoscopy is thetraditionalmethod of examination of the oesophageal lumen. Many of the functions traditionally fulfilled by such an examination have now been superseded by flexible fibre-optic oesophagoscopy (see Flexible OesophagoscopyChapter 39). Rigid oesophagoscopy remainsthe preferred method for removal of oesophageal foreign bodies and in some circumstances may still be used for the dilatation of oesophageal luminal stricture and the biopsy of endoluminal lesions. In expert hands, this is a safe procedure, but for theinexperienced operator there remains a relatively high risk of inadvertent oesophageal laceration and perforation. Perhaps the principal reason behind its finding continuedfavouramong otolaryngologists is deficient tuition of trainees in the use of the flexible endoscope. Preoperative management

A contrast examination of the oesophagus is mandatory priorto rigid oesophagoscopy in order to exclude pre-existing traumaticperforation by a foreign body and to delineate abnormalities which may significantly increase the rate of accidental perforation, e.g. cervical osteophytes, diverticulae, prestenotic dilatations and tumours. In thelatter case this may be the only way to define the lower limit of a lesion (Stell, 1979). A plain chest radiographshouldalso be taken to identify any gross cardiovascularabnormality which may compromise the examination, e.g. massive cardiomegaly. Operative technique and procedure

The patient is placed supine on the table with a pillow placed underneath the shoulders and neck to achieve minor neck extension and marked head extension (Fig. 38.3). The position is maintained by placing the forefinger of the left handon thehardpalateandpalatal surface of the incisor teeth, while the lower lip is retracted using the third finger. The oesophagoscope is inserted into the mouth and advanced until theuvula is visualised. Observation is maintainedthroughthelumen of the endoscope at all times. The oesophagoscope

Pharyngo~aryngoscop~and Rigid Oesophagoscopy

Fig. 38.3 Positioning for rigid oesophagoscopy. Breaking the table may assist with examination of the distal third of the oesophagus. The pillow supports the shoulders and neck in the correct position.

is then lowered such that it rests on the thumb of the left hand, thus protecting the upper dentition. If necessary, this thumb may be used as a fulcrum. At no time should the upper dentition be used as a fulcrum. The thumb is used to advance the scope and at the same time some minorrotatory movements withtherighthand will facilitate the passage of the tip of the scope. The aim of observation via the lumen of the scope is to maintain the centre of the lumen through which it is intended to pass the scope in direct alignmentwiththecentre of the observed field. The scope is then advanced intothe hypopharynx off-centre, such that it is possible to visualise theright aryepiglottic fold and theright pyriform sinus. The scope is thenadvancedintothe pyriform sinus and sweptintothe midline asit is advanced, so that it comes to lie behind the posterior lamina of the cricoid. At this point, the puckered inlet at the cricopharyngeus should become visible. Inadequate muscle relaxation and toniccontraction of thecricopharyngeus may impede passage of the oesophagoscope intotheupper oesophageal lumen. Gentle dilatatory pressure with the beak of the oesophagoscope at this point shouldbe maintained until cricopharyngealrelaxation is achieved and thetip of the oesophaguspasses with ease into the upper oesophagus. Attempts tohurry theprocedure at this stage may cause traumaand should be avoided. Oncethe endoscope is in the upper oesophageal lumen, its tip is

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advanced, using similar rotatory movements and left thumb pressure, untilthepulsatingindentation of theaorticarch is identified. At this point,the oesophagus will tend to curve anterolaterally to the left and this may cause some difficulty with the advancement of the scope. In kyphotic patients it may be necessary to extend the back and thus align the axes of the upper and lower oesophageal segments. This may be achieved by breakingtheoperating table. The distal segment of the oesophagus should then be examined in the same manner, but with great care, given that the directional stability of the tip of the oesophagoscope is somewhat reduced by thereduction in the lever arm between the proximal end of the oesophagoscope and the fulcrum on the left thumb. Care should be taken to assess not only the mucosal integrity of the oesophageal lumen, but also the presence of any reflux or indenting mass lesion. Examination should be continued during the removal of the endoscope. Particularattention should be paid to the cricopharyngeal inlet and postcricoid regions, where rotation of the beak of the scope to produce distension, andthusto display all segments of the oesophageal wall, will greatly facilitate the examination. Postoperative management

Where the examination has been uneventful and there has been no recognisable laceration or breach of the oesophageal mucosa, the patient shouldbe kept on clear fluids for 6 h postoperatively. Thereafter a normal diet may be reintroduced. Given the risk of silent perforation, close attention should be paid to the acute onsetof pain(particularlywhere it is pleuritic and radiating through to the interscapular region), fever, tachycardia and collapse, as all these may indicate oesophageal perforation. Where oesophageal perforation is recognised, initial treatment may be conservative, with the passage of a nasogastric tube and the immediate institution of a nil-by-mouth regimen and intravenous broad-spectrum antibiotics, e.g. acephalosporinwith metronidazole. Continuous close observation is essential duringthis period as further deteriorationindicates that open surgical closure of the perforation may be necessary. Healing may be assessed with contrast studies, and where recovery is protracted it may be necessary to institute parenteral feeding. Where there is gross thoracic contamination or associated pneumothorax, openclosure is indicated. Bleeding from traumatised oesophageal varices or endoluminal tumours may require endoluminal compression with balloons or open surgical management.

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Alternative procedures

It is possible to perform most of the procedures traditionally reserved for rigid endoscopy with thefibre-optic endoscope. One exception is atraumatic removal of impacted foreign bodies. The distension of the oesophagus achieved with the rigid oesophagoscope facilitates disimpaction and may allow lysis of the impacted foreign body and its subsequent atraumatic removal in the lumen of the oesophagoscope. To a large extent, balloon dilatation has now superseded the bougienage of oesophageal stricture.

Panendoscopy Panendoscopy is the systematic inspection of the upper aerodigestive tract to establish the site of aprimary tumour responsible for a malignant cervical node, or to exclude the presence of a synchronous or metachronous primary tumour. Itcomprises systematic examination of the mouth, pharynx, postnasal space, larynx, oesophagus, trachea and main bronchi, with palpation and with biopsies fromthepostnasal space and tongue base. Some alsoadvocate tonsillectomy on the side of the malignantnode. Close cooperation between surgeon and anaesthetist is essential, as they will be required to share the airway during the procedure. It will be necessary to change the position of the patient during the examination and hence the stability of the ET may be

endangered if it is not carefully maintained. It is wise to perform examinations of all areas to be inspected prior to taking biopsies as bleeding may compromise subsequent inspection and reduce the efficacy of the whole process in establishing a diagnosis. Examination of the mouth

Examination of the mouth canusually be achieved without anaesthesia unless there is marked trismus or pain resulting from a lesion in the mouth or pharynx. Care should be taken to inspect and palpate all regions of the mouth. Biopsies should be guided by the presence of obvious lesions on examination and palpation. Pharyngolaryngoscopy

This is performed as described previously. Examination of the nasopharynx (see also Nasopharyngoscopy-Chapter 37)

With the patient lying supine, a Boyle-Davis tonsillectomy gag is inserted and its positionmaintained by suspension (Fig. 38.4). Soft catheters are passed through the nostrils and brought outthrough themouth. By gentle traction on theends of thecatheters,thesoft palate is elevated off the posterior pharyngeal wall, allowing access to the nasopharynx from the oropharynx.

Fig. 38.4 Examination of the postnasal space with the operating microscope.

PharyngolaryngoscopyandRigidOesophagoscopy The postnasal space may then be examined, using either a 120" rigid endoscope or a laryngeal mirror (previously warmed to prevent misting). The use of an operating microscope improves the accuracy of mirror examination. The posterior end of the nasal septum and nasal choanae, Eustachian tube orifices and cushions, fossae of Rosenmuller, nasopharyngealroof and posterior wall are systematically examined. Guided biopsies are taken from the fossae of Rosenmuller and the posterior pharyngeal wall on the side of the involved node. This is the mostproximalanatomical segment examinedduring panendoscopy, and bleedingmay thuscontaminate all other areas of examination. The taking of nasopharyngeal biopsies should thus be the last part of the procedure. Biopsies are taken under mirror control, using Tilley-Henckel or similar forceps inserted through the ipsilateral nostriland keeping the shaftof the instrument against thefloor of the nose. Care shouldbe taken to avoid trauma during introduction of the instrument as this may cause bleeding and compromise visualisation during biopsy. Palpation of the postnasal space and soft palate forms an essential part of the examination, but should be delayed until all other areas havebeen examined, as it may cause bleeding. Oesophagoscopy

Oesophagoscopy should be performed as above, or alternatively flexible oesophagoscopy with vital staining may be substituted.

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Bronchoscopy

Traditionally bronchoscopy is performed using a rigid ventilating bronchoscope. The only advantage of rigid bronchoscopy over fibre-optic examination via the endotracheal tube is that the proximal trachea may be examined instead of being bypassed. Many feel that the inclusion of rigid bronchoscopy in panendoscopy is no longer indicated and that flexible bronchoscopy at the same or another sitting will suffice (Fulkerson, 1984). Proximal tracheoscopy can usually be achieved during laryngoscopy, particularly if a jet ventilator or Venturi injector is used to maintain ventilation during laryngoscopy.

References Fulkerson JW (1984) Medical intelligence: current concepts of fibreoptic bronchoscopy. N.Engl. J . Med. 311, 511-15. Kleinsasser 0 (1992) Microlaryngoscopy and Endolaryngeal Microsurgery:TechniqueandTypicalFindings (3rd edn). Hanley and Belfus. Stell PM (1979)Diseases of the hypopharynx. In: Maran AGD & Stell PM(eds) ClinicalOtolaryngology. Oxford, Blackwell Scientific Publications, p. 368-381. Thomson HG & Batch AJ (1989) Flexible oesophagogastroscopy in otolaryngology. J . Laryngo. Otol. 103, 399-1103.

Flexible Oesophagoscopy CHARLES S. R O B E R T S O N

Introduction Flexible oesophagoscopy is rarely performed in isolationbut is usually apart of aroutineupper gastrointestinal (GI) survey. This includes inspection of the oesophagus, stomach,pylorus and first and second parts of the duodenum. It is now usual to use a small-diameter, forward-viewing video-endoscope, which is easy to pass andmanoeuvreand gives a bright, high-definition view that can be seen by boththeendoscopist and assistants on a television monitor.

Indications for upper gastrointestinal endoscopy 1 For the investigation of: (a) theupper aerodigestive tractforsynchronous squamous cancers; (b) dysphagia; (c) chronic upper abdominal pain; (d) symptoms of gastro-oesophageal reflux; (e) upper GI bleeding; (f) iron-deficiency anaemia. 2 For the treatment of: (a) foreign bodies; (b) benign oesophageal strictures; (c) oesophageal cancer; (d) upper GI bleeding. 3 For theinsertion of apercutaneous endoscopic gastrostomy (PEG) feeding tube.

Contraindications These are all relative and related to the patient’s general

condition -especially severe cardiovascular or respiratory disease.

Patient preparation Patients are starved for 6 h prior to the examination. The endoscopist is responsible forensuring that the examination is indicated and that the patient is fit for and understands the nature of the procedure, following which written informed consent can be obtained. Dentures and glasses are removed.

Sedation Pharyngeal anaesthesia

Local anaesthetic spray to the pharynx may be helpful to suppress the gag reflex when no IV sedation is used. However, it is probably unnecessary if sedation is used, as it is bitter and unpleasant, may increase the risk of pulmonaryaspiration and prevents thepatientfrom drinking for 30 min postprocedure. Conscious sedation

Upper GI endoscopy can be performed without sedation but may be distressing for the patient. The major advantage is that no formal recovery is required and that the patient can resume normal activities immediately. However, most endoscopists prefer to sedate their patients, using IV drugs. This allowspassage and manipulation of the endoscope witha relaxed but responsive patient, able to maintain their vital functions. All drugs must be given slowly and titrated individually until ptosis of the eyelids and slurring of speech occur. Great care mustbe

Flexible Oesophagoscopy

takenwiththe elderly and thosewithknown liver, cardiac or respiratory disease. General anaesthesia is usually required for children and rarely for an otherwise uncontrollable patient. Drugs used in upper gastrointestinal endoscopy

Benzodiazepines

These drugsproducesedationwith amnesia and are, therefore, popular for IV use. The two most popular agents are Diazemuls (a lipid emulsion of diazepam which prevents thrombophlebitis) and midazolam (a water-soluble compound which does not cause thrombophlebitis).Midazolamhasafasteronset and shorterduration of action than Diazemuls. Smaller doses must be used to prevent hypoxia.

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Non-invasive blood-pressure and ECG monitoring are probably not indicated routinely. Oxygen should be administered via nasal cannulae to all patients.

The nurse’s role Ideally a minimum of two nurses assist at the examination. One nurse concentrates on the patient and stands behind the patient’s head giving reassurance, and ensuring an adequateairway, using suctionas necessary. From this position the nurse can also keep the mouthguard in position andcontrol thearms of a restless patient. Another nurse assists the endoscopist, concentratingonthe procedure,holding or moving the endoscopewhenasked and helping withtherapeutic manoeuvres (Fig. 39.1 ).

Procedure

Benzodiazepine reversal

Positioning

Benzodiazepines can be reversed using flumazenil 500 pg IV over 30 S . Its action is rapid but short-lived, so repeat doses may be necessary.

The patient is placed in the left lateral position with the head on a pillow covered with an absorbent towel. The neck is semiflexed. IV access is established in the right arm as flow in the dependent left arm may be variable. A mouth-guard is placed before thepatient becomes drowsy to protect the patient’s teeth and the endoscope.

Opiates

Pethidine 25-50mg is often used in combination with a smaller dose of benzodiazepine. As both agents cause respiratory depression, caution must be used if they are given together.

Opiate reversal Opiates can be reversed using naloxone 0.2-0.4mg IV. Its action is rapid but short-lived, so that repeat doses may be necessary. Hyoscine butylbromide

This may be given in doses from 20 to 40mg IV to paralyse the duodenum in order to aid inspection or to performtherapeutic manoeuvres. Its effects last less than 1Omin andit is therefore only given oncethe endoscope has passed the pylorus.

Patient monitoring This should be proportional to the perceived risk to the individualpatientundergoingthe specific procedure. Measurement of the pulse and tissue oxygen saturation using pulse oximetry is now usual and recommended.

Fig. 39.1 Patient and nurse positioning for flexible oesophagoscopy.

Passing the endoscope

The endoscopeis prechecked for proper functioningand thetiplubricatedwithaqueous gel. The endoscope should then be passed under direct vision, The tip of the scope is flexed, using the controls which are held in the left hand, and its alignment adjusted so that,when inserted through the mouth-guard, the tip naturally follows over the back of the tongue to pass into the posterior pharynx. The tipis then straightened, using the left hand thumb onthe up/down control. Thescope is gently advanced and the patient asked to swallow to relax the cricopharyngeus. In a routine survey, the oesophagus, stomach and first and second parts of the duodenum are examined. The endoscope is advanced under direct vision, using air insufflation and suction as required. If unsure o f the scope’s location due to loss of view or disorientation,thenthe scope must not be advanced ‘blind’ but should be withdrawn slightly. Any lesions seen should have theirpositionnoted,and biopsies and brushings are taken for histology and cytology if appropriate. Special care must be taken to examine the upperthird of theoesophagus on withdrawal as the endoscopeoften passes throughthisarea quickly on insertion, preventing an adequate view. The endoscopic landmark in theloweroesophagus is thesquamocolumnar mucosal junction, usually marking the oesophagogastric junction, which should lie at the level of the diaphragmatic hiatus (Fig. 39.2). This mucosal interface, where the pale pinkoesophageal mucosa meets the darker red gastric mucosa, is also known as the ‘Z-line’, and is normallylocatedapproximately 40cm from the incisors in adults. If the Z-line lies proximal to the diaphragmatic hiatus, then either a sliding hiatus hernia or a columnar-lined oesophagus (Barrett’s oesophagus) is present. The endoscope can then be advanced into the stomach through the pylorus and into the duodenum.

Recovery and discharge of day cases Following IV sedation most patients requirebetween 15 and 3Omin on a trolley before being able to be transferred to a chair to recover. By 1h postprocedure, patients are able to be discharged home with supervision. Prior to discharge they are given an information sheet. This includes details of the examination findings, follow-up arrangements and instructions emphasising that the patient must not drive or operate heavy machinery for 242.1.

Fig. 39.2 Endoscopic landmarks.

Complications Drug=induced respirato

As discussed, great care must be taken in using IV sedation, especially in elderly and infirm patients. Perforation of t

This occurs in less than 0.1% of cases and is more common when the endoscope is inserted blind, when a severely diseased organ or diverticulum is present, and duringtherapeutic manoeuvres. Typically thepatient complains of pain, and may be pyrexial. Surgical emphysema may be present. Free gas may be visible on abdominal X-ray or pneumomediastinum, a pneumothorax or pleuraleffusion on chest X-ray. Management will depend on the site of the perforation and the patient’s pathology, Puimonary aspiration

This is most likely in elderly patients, when the cough reflex has been suppressed and in the presence of excessive sedation. Minor degrees may be common but major problems are rare.

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Infection hazards

Infection of endoscopy personnel

Patient-to-patient infection

This should be avoided by adopting recommended procedures with blood and gastrointestinal secretions.

This shouldbeeliminated by following thecorrect recommendations for sterilising the endoscope and accessones. Bacteraemia

This is probably very rare but it is advised that patients with prosthetic heart valves are given amoxycillin and gentamicin to cover upper GI endoscopy.

Further reading Baiiiie J (1992) Gastrointestinal Endoscopy: BasicPrinciples and Practice. London, Butterworths. Cotton PB & Williams CB (1996) Practical Gastrointestinal Endoscopy, 4th edn. Oxford, Blackwell Science.

Rigid Bronchosc VICTOR ABDULLAH

Custav Killian of Freiburg, the father of bronchoscopy, modified theskeletonoesophagoscope to view the tracheobronchialtree in 1897 (Stevenson &C Guthrie, 1949). Today, a century later, many different types of rigid bronchoscopes are available. Most of these instrumentsareequippedwithfibreopticillumination and providequality magnifiedimages through specially adapted glass lenses. The typicalmodern universal bronchoscope has side-ports, which allow ventilation, suction and fibreoptically transmissible laser to be effectively and efficiently delivered. The modern universal rigid bronchoscope, apart from its diagnostic use, has provided for safer and more controlled performance of interventionalprocedures down thetracheobronchial tree for obstructive lesions. The rigid bronchoscope is particularly well suited for such procedures as isiteffectively an optically guided endotracheal ventilation tube (VT). A furthermerit is itswide-borelumen,which allows the ready removalof large blood clots and tissue debris,which, not infrequently,accompany interventional procedures. Whichever rigid bronchoscope is used and for whatever purpose, a safe method of insertion and advancement must be mastered.. Familiarity with the specific bronchoscope and a sound knowledge of the anatomy of the tracheobronchial tree and its important relations are essential prerequisites (Figs 40.1 and 40.2).

the heart, whichis its anteroinferior relation. Important relations of the cervical trachea include the isthmus of the thyroid lying over the second, third and fourth tracheal rings, the thyroid lobes laterally and the cervical oesophagusposteriorly.Inthe thorax,the trachea is flanked by the innominate arteries laterally. The thoracic oesophagus lies posteriorly and takes a gentle left turn to pass behind the left main bronchus. The distal trachea has the aortic arch lying on its left. Between the trachea and the alveolar sacs, the airway divides 23 times. The rigid bronchoscope, however,only allows examinationof the orifices of the third bronchial division. Thebronchopulmonarysegmentalopenings may be inspected just beyond thethirdbronchial divisions. The right main bronchus hastwo importantrelations. Passing over it from posteriorly to reach the superior vena cava is the azygos vein. The right pulmonary artery lies first below and then anterior to it (Fig. 40.2). The right upper-lobe bronchus takes off above the pulmonaryarteryand hence it is often described asthe ‘eparterial bronchus’, All other lobar bronchi, right and left, liebelow their respective pulmonary arteries and are termed ‘hyparterial bronchi’. The left main bronchus has the aortic arch above with the oesophagus and thedescending aorta as its posterior relations.

Anatomy

lndications

The adult trachea measures on average 12cm in length and is 2cm wide, with its patency maintained by 15 to 20 U-shaped cartilages. The right main bronchus, being 2.5cm long, is shorter, wider and morevertical than the left, which measures 5cm in length. The carina sits over

1 Diagnostic and routine examination

of

the

tracheobronchial tree. 2 Removal of a foreign body. 3 Interventional procedures such as laser widening or stent insertion for obstructive tracheobronchial lesions. 280

Rigid Bronchoscopy

28 I

4 The urgent establishment of an airway in upper airway obstruction if intubation fails.

Anaesthesia The author prefers the use of spontaneous assisted ventilation with gas induction or continuous IV propofol infusion anaesthesia. Oncethepatient is asleep, the larynx is sprayed twice or three times with 10% xylocaine spray using the Macintosh laryngoscope. Additional sprays can be delivered to the carina via the bronchoscope once it is inserted, using the long spray nozzle. Anaesthetic gas and/or oxygen is delivered via the bronchoscope’s ventilation channel throughout the procedure,withthepatientbreathingspontaneously. This can be assisted with bagging through the circuit if required.Mechanicalventilation and oxygen Venturi ventilation are alternatives to the above.

Procedure Position Right main bronchus

Fig. 40.1 Anatomical relationships of the trachea (posterior view).

The patient shouldbe supine with his head 2-3 cm from the edge of the bed. The insertion can be facilitated by the use of a shoulder support and gentle flexion of the cervical spine withthe head extended to rest on a head ring. This brings the trachea to a more horizontal position. Procedure

Oesophagus

Fig. 40.2 Structures crossing the right and left main bronchi.

The upper teeth should be protected with a tooth guard and the gums of an edentulous patient with a piece of saline-soaked gauze. The right-handed surgeon should use his left hand to open and steady the mouth. Theleft middle finger is used to support the hard palate while lifting it cranially. The left forefinger is used to displace the lower lip downwards to avoid it being rolled inwards and injured during insertion. The left thumb is used to support the scope while keeping it away from the upper teeth or gum. The best position for the insertion of the bronchoscope is from the side which allows an easier excursion and minimal leverage. The right side is preferred as thehead would be out of the way for the righthanded surgeon. Until the trachea has been entered, it is essential to keep the beak of the bronchoscope in sight. This applies in particular to bronchoscopes with adapted Hopkin’s rods. If the beak cannot be seen, the rod should be withdrawn during insertion orelse laryngeal injuries can easily be inflicted.

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Chapter 40

The scope should be lightly lubricated. Keeping the lobe segmental openings except with special-angled beak in the 12 o'clock position, it is used to displace the Hopkin's lenses. Figure 40.4 illustratesthe different tongue forward and away from the posterior pharyngealviews from different positions down theright main wall. The identification of the epiglottis is easy but its bronchus. elevation can be tricky. One should avoid flicking the Once the examination of the right main bronchus is epiglottis repeatedly but pass the scope straight on tothe completed, the scope can be retrieved to a position just arytenoids. The beak can then be elevated to reveal the above the carinawhile returning the head of the patient vocal cords (Fig. 40.3). The bronchoscope is then rotated 90" clockwise. With the bronchoscopic view centred on theleft vocal cord, the tip can be placed between the cords. The scope is then advanced while being rotated back 90" anticlockwise. This manoeuvre facilitates the passage through the glottis. The trachea now comes into view. Once in the trachea, the bronchoscope should be kept in the centre of the lumen at all times. The scope can be advanced while inspecting thetracheal wall until the distinct sharp edge of the carina is reached. It is more convenient to inspect therightmain bronchus first as it is more vertical and thus easier to enter. With the patient's head rotated to the left, the scope can be advanced down the right main bronchus. The first lumen to beviewedis therightupper-lobe Fig. 40.3 Bronchoscopic view showing advancement of bronchus. It is usually not possible to view the upperbronchoscope to the posterior arytenoids.

l

\Posterior basal

Fig. 40.4 Bronchoscopic views down the right main bronchus at positions (a) and (b). (Top, anterior; bottom, posterior.)

Rigid Bronchoscopy to the central position. The head can now be turned to the right side to facilitate the inspection of the left main bronchus. It is usually necessary to turn the head a little furtherasthe left main bronchustakes off more obliquely. The left main bronchus is narrower and twice as long as the right. Once inside, two openings separated by a ridge which looks just like the carina can be seen. This ridge is termed the subcarina or secondary carina. The upper opening contains the upperand lingular-lobe bronchi and the lower opening is the lower-lobe bronchus with its segmental openings (Fig. 40.5). The retrieval of foreign bodies fromthetracheobronchial tree is a not uncommon indication for rigid bronchoscopy, even in the adult population. During the procedure, the beak of the bronchoscope should be kept a short distance away from the foreign body to avoid displacing it further down the airway or createbleeding from surrounding granulationtissue. Bleeding around a foreign body can be minimised by a few drops of 1:20 000 adrenaline. The removal of the foreign body can be effectively performed using a Fogarty balloon, a wire basket or different types of grasping forceps. The choice of instrument depends on the nature, shape and size of the foreign body. Optical grasping forceps supersede others as they can be accurately applied with the least amount of trauma. The anaesthetist should be informed once the examination is complete so that appropriate equipment is at hand once the scope is removed.

Fibreoptically transmissible lasers such as Nd-YAG, argon and potassium-titanylphosphate(KTP) canbe effectively delivered down a flexible or rigid bronchoscope.

Fig. 40.5 Bronchoscopic view down the left main bronchus at position (a). (TOP, anterior; bottom, posterior.)

283

The rigid bronchoscope is preferred for photoablation of obstructive intraluminal tumoursbecause of the more effective evacuation of tissue debris and blood clots. The Nd-YAG laser is a gas laser emitted at a wavelength of 1064 nm. Its deeper penetration, maximally at 1.5cm, rendersitmost useful for removal of large vascular lesions in the trachea or bronchi. The argon laser is a gas laser in the blue-green region of visible light. It only penetrates 1-2mm and is useful for vaporising superficial tumours of the tracheobronchial tree. The KTP laser is similar to argon. Its wavelength of 532nm is close to the peak absorption spectrum of haemoglobin, making it more suitable for superficial vascular lesions. The CO, laser has a wavelength of 10600nm and a depth of penetration of approximately 10nm. It is not fibreoptically transmissible. Its minimal scatter allows precise cutting and lessens collateraldamage to surrounding tissues. The CO, laser, however, is inferior to the above-mentioned lasers in its haemostatic ability. It nevertheless remains an effective laser for removing granulation tissue, limited stenosis and respiratory papillomata within the tracheobronchial tree. Respiratory papillomata are pale in colour with small bloodvessels and careful use of the CO, laser allows precise vaporisation without damaging the underlying perichondrium and cartilage. Granulations following a tracheostomy and infiltrates of amyloidosis are also amenable to CO:, laser removal. This laser is less suitableforcytoreduction of malignantintraluminaltumours as bleeding can occur. The CO, laser bronchoscope requires a specially designed coupling device for laser transmission. The method of insertion of the CO, laser bronchoscope is as described above. Whenever possible, the scope should be passed to a more distal position clear of the obstruc-

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Fig. 40.6 Radial laser incisions for circumferential stenosis of the trachea.

tive lesion to optimise ventilation, and one can then work from distal to proximal. The bronchoscope itself often proves to be an effective optically guided dilator. Lasering should be performed from the centre of the lesion, leaving a rim of tissue on the tracheal wall to prevent its penetration. When widening tracheal stenoses, it is importantto use radial incisions (Fig. 40.6) to avoid circumferential laser-induced injury (Shapshay et al., 1987’).It is necessary to uncouple the coupling device intermittently to allow suction or forceps removal of charred tissue. Whichever laser is used, the operator shouldbe familiar with its potential hazards. It is the surgeon’s duty to ensure that the patient and all who are present in the theatre are adequately protected against the dangers of that particular laser.

ornplications of bronchoscopy 1 Injuries to the lips, teeth, gum and tongueare not uncommon.

2 Laryngeal oedema may occursecondary to either rough insertion or prolonged examination. Dexamethasone 10mg IVfollowed by two furtherdoses 8 h apart should be given. The patient is put on airway and oximetric monitoring on the ward. 3 Haemorrhage.Thiscan usually be controlled by tamponadewithapeanut gauze soaked in dilute epinephrine (1:20 000). Epinephrinesolutioncan be instilled via bronchoscope the the into tracheobronchial tree. Electrocautery or the Nd-YAG laser are effective coagulators if available. A Fogarty venous occlusion catheter can be used for more severe haemorrhage. 4 Penetration of the wall of the trachea and bronchi. Sudden development of surgical emphysema, oxygen desaturation and lung collapse can occur and require urgent insertion of chest drains and ventilatory support.

References and further rea Cordasco EM, Jr, Mehta AC & Ahmad M (1991) Bronchoscopicallyinduced bleeding: a summary of nine years’ Cleveland Clinic experience and review of the literature. Chest. 100, 1141-7. Ossoff RH, Karlan MS (1992) Universal endoscopic coupler for carbon dioxide laser surgery. Ann. Otol. Rhinol. Laryngol. 91,608-9. Prakash UBS (1994) Bronchoscopy. New York, Raven Press. Shapshay SM (1990) Laser Bronchoscopy: Lasers in Philadelphia, W.B. Otolaryngology-HeadandNeckSurgery. Saunders, pp. 85-105. Shapshay SM, Beamis JF, Jr, Hybels RL & Bohigian RK (1987) Endoscopic treatment of subglottic and tracheal stenosis by radial laser incision and dilation. Ann. Otol. Rhinol. Laryngol. 99, 6614. Stevenson RS & Guthrie D (1949) A History of Otolaryngology. Edinburgh, E & S Livingstone, pp. 130-7.

ssessrnent of the Paediatric Airway: Laryngotracheobronchoscopy DAVID ALBERT

Introduction Most paediatric airway endoscopies are performed for the investigation of stridor. A standardised techniquein these cases ensures that examination is comprehensive, and this technique is described first. Examinations for otherindications(suchasbronchoscopy for foreign bodies or to specifically assess dynamic conditions such as cord palsies) arebest achieved using modifications of this technique, and these modified techniques will therefore be described separately. Laryngotracheobronchoscopy (LTB) is now a highly technical procedure and thewholeteam(surgeon, anaesthetist and nursing assistant) need to fully understand the equipmentto perform the examination safely, and to optimise the assessment. Ideally, the same surgeon, anaesthetistandnurseshouldroutinely work together. The advent of video has improved training.It has also made the assessment safer, as the anaesthetist can monitor progress on the screen and the nurse can be ready with equipment for the next stage. If the examination is for assessment, it is vital that accuraterecordsarekept to allowcomparisonwith future examinations. Thisis facilitated by using a standardised form within a department (Fig. 41.1). Use of a recognised staging system (Fig. 41.2) is important for publication of results. Polaroid prints from the video form a valid record for static conditions, while for dynamic conditions a videotape is unparalleled.

Indications for bronchoscopy Stridor is thecommonestindication by far. Not all children with congenital stridor require bronchoscopy

(Table 41.1), although stridor that appears later in life and persists doesrequire full investigation. The main indications are given in Table 41.2.

History To determine the cause

First stridor mustbe distinguished from stertor. This can be difficult though an impersonation of each type of noisy breathingmay help. Stertortends to be worse during sleep, while stridor is worse when the child is feeding, upset or exercising. Laryngomalacia usually develops in the first few weeks of life. A history of prolonged intubation may suggest subglottic stenosis, interarytenoid scarring or tracheal stenosis, while previous thoracic surgerymayhave causedacord palsy. An abnormal voice or cry suggests pathology at the laryngeal level, such as papillomatosis or, if congenital, aweb.Patientswitharepairedtracheo-oesophageal (TE) fistula may have associated tracheomalacia or occasionally a laryngeal cleft. Thiscausesrecurrent pneumonias, as well asaspirationduring feeding. In paediatric airway obstruction, the history is seldom so characteristic that a positive diagnosis can be made. To assess the severity of airway obstruction

Most parents will be able accurately to describe recession and the effect of airway obstruction on feeding. Many will be informed about poor growth. However, apnoeic episodes always seemlonger to a parent, although cyanosis, if described, is a suresign that a significant event has occurred.

Chapter 41

286 ~

. . . . . . . . .

~

OPERATI

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. "

. . " .

"

-

.

.

"

--

-

. ". . . . . .

. . .

P

MLB Nature of operation: .......................................... Date carried out: ................................................ Surgeon: ...................................................... Assistant: .................................................... Anaesthetist: ...............................................

History:

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Working diagnosis: ..................................... Tracheostomy:

Yes

N o ...........

. . . . . . . . . .

Report

Epiglottis: ..........................................................

Type of laryngoscope: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

Aryepiglottic folds: ........................................... Arytenoid mobility: ......................................... ? Laryngeal cleft: .............................................. Vocal cords: Function: .................................. Appearance:

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Tranchea: .......................................................... ?Suprastoma1 collapse:.................................... Carina: .............................................................. Bronchi:

Size of bronchoscope: ................... Size of ET tube: ..............................

Right: ......................................... Left: ...........................................

Photograph

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ." .

Impression and plan

Yes

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No

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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fig. 41.1 A standardised form for documentation.

Table 41.1 When to scope a child with congenital stridor (e.g.

stridor starting within 1 week of birth).

Inspiratory stridor is usually laryngeal while expiratory stridor suggests an intrathoracic cause. Do notbe misled by the child whose stridor seems to have improved, as this may be due toworsening air flow. General examination may reveal features of craniofacial syndromes or isolated maxillary or mandibular hypoplasia. Children withDown'ssyndrome have an increased risk of subglottic stenosis. Cutaneous haemangiomas are present in about 30% of patientswithsubglottic haemangiomas.

Assessment of the Paediatric Airway

287

2 Undamaged light leads. 3 Laryngoscopes (Fig. 41.3):

50% obstruction

70% obstruction

Fig. 41.2 Staging of stenosis. With the permission of Ann. Otol. Rhinol. Laryngol. Table 41.2 Main indication for bronchoscopy.

(a) Benjamin (anterior pathology); (b) Lindholm (posterior pathology); (c) Kleinsasser (general). 4 Laryngostat (Lewy jack is too heavy for neonates) (Fig. 41.4). 5 Laryngeal probes and forceps. 6 Full range of ventilating bronchoscopes to accept Storz-Hopkins telescopes. 7 Spaghetti suckers passed alongside telescope if using >3mm bronchoscope. 8 Side-arm forceps and peanut-extraction forceps (requires extra long telescope) (Fig. 41.5). 9 Video camera attached for microscope. 10 Video cameraattached direct to bronchoscope so that bronchoscopy is performed by looking at video screen. 11 Video printerhide0 recorder, invaluable for documentation. 12 Neurosurgicalmicropattiessoaked in 1:100 000 adrenalineare excellent forcontrolling oedema and bleeding.

Standard technique Anaesthetic

Preoperative investigations (not always necessary) 1 Lateral neck X-ray. 2 Cincinnati view: penetrated anterior -posterior (A-P) chest to show major airways. 3 Barium swallow: this cannotbe used to exclude reflux but screening may demonstrate tracheomalacia.

Key equipment 1 Xenon light source with feedback intensity control.

IM atropine is vital for a drysurgical field and toensure that the topical anaesthetic is effective. An IV induction is preferable for older children, although gas induction may be needed in infants and those with a precarious airway. IV suxamethonium can be given if the patient is stable and should be given prior to the lignocaine spray to avoid laryngeal spasm and to facilitate intubation. Nasotracheal intubation allows the endotracheal tube (ET) to be withdrawn into the nasopharynx once the child is breathing spontaneously. Halothaneand oxygen maintain a level of anaesthesia that allows a thorough examination in a child who is breathing spontaneously. The anaesthetist needs to be able to control anaesthesia in response to surgical conditions and for this a video monitor is invaluable. Preoperative steroids are a good safegaurd if significant stenosis is suspected. In experienced hands, a technique of not intubating at all allows the surgeon a view of the larynx prior to any instrumentation. Microlaryngoscopy

A small sandbag is usually required under the shoulders to greatly extend the neck, and expremature neonates

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Fig. 41.3 Laryngoscopes: (i) paediatric Kleinsasser; (ii) Benjamin; (iii) Lindholm.

Fig. 41.4 Laryngostat.

Assessment of the Paediatric Airway

289

that the arytenoids are splinted, preventing assessment of arytenoid movement. Childrenwithlaryngomalacia tend to have tall (superiorly) but short (anteroposteriorly) aryepiglottic folds which approximate the epiglottis to the arytenoids; this is best appreciated with a Lindholm scope in the vallecula. Finally, use a probe to check the vocal cords and ventricles. Double-check that the appropriate bronchoscope is available before the anaesthetist withdraws the tube into the pharynx under video control. Laryngeal examination with endotracheal tube removed Fig. 41.5 Foreign body extraction forceps. Long telescope forceps.

fits inside

may need sandbags laterally to support their long thin heads. A Mayo table supports the laryngostat clear of the chest. Prepare and check equipment: 1 check microscope and video; (a) use a 400 mm lens to allow use of standard laryngeal instruments; (b) use a 350mm lens to aid manipulation of larynx (particularly in small neonates); 2 check bronchoscope size and telescopes; 3 antifogsolution needs to be freshly applied to the telescope lens to be effective.

Using a probe, gently check for cricoarytenoid fixation by moving the arytenoids independently; then exclude an interarytenoidscar by trying to separatethetwo arytenoids. A posterior laryngeal cleft is excluded by passing the probe between the arytenoids, comparing the lower limit of the interarytenoid groove withthat of the posterior commissure. Finally, move the cords apart to inspect the subglottis. The time available will depend on the airway. In a child breathingspontaneouslywithanormalairway andnormal lung function, anaesthesia can be maintained solely by the use of inhalational agents from the ET withdrawn into the pharynx.In others, the time may be very limited and it is essential to be prepared to move ahead with bronchoscopy at any stage.

Laryngeal examination with endotracheal tube in place

Insert the lubricated laryngoscope, protecting the teeth and lips and keeping the tongue central, if possible, to provide a well-centred view. As in adults, check the overall appearance of supraglottis the and laryngopharynx during introduction of the laryngoscope. Follow the ET, if present, to the tip of the epiglottis and then gently lift the epiglottis forwards. This is easiest witha Benjamin laryngoscope. Make certain that the epiglottis does not curl upin front of the laryngoscope, preventing a complete view of the anterior commissure (Fig. 41.6). If necessary, relubricate the tip of the scope. Check if in doubt by gently withdrawing the laryngoscope, as a curled epiglottis is the commonest fault in those learning the technique of paediatric laryngoscopy. Often this is a particular problem in older children with a tracheostomy, in which case an anaesthetic laryngoscope placed in the vallecula can help. Do not insert the laryngoscope so far into the larynx

Fig. 41.6 To show poor posterior view if epiglottis becomes invaginated.

If anaesthesia is stable, a sucker can be placed in the laryngeal inlet to mimic laryngomalacia -the 'Narcy test'. Photographs can be taken at this stage with a-wide angle Storz photographic telescope. If there is significant subglottic stenosis, an ultrafine telescope passed through the laryngoscope will cause less trauma than a bronchoscope.

Select the age-appropriate bronchoscope (Fig. 41.7') unless stenosis is suspected, but always have available smaller bronchoscopes. Use an anaesthetic laryngoscope in the vallecula to lift thelarynxforward, while passing the bevel of the

bronchoscope through the vocal cords under video control on the monitor. Avoid impacting the ventricle with the bevel of thebronchoscope.Change to a smaller bronchoscope if resistance is felt with the bronchoscope placed centrally to avoid unintenionally dilating any stenosis. Establish a pattern of examination so that the main bronchi, the carina, the trachea and the subglottis areall systematically examined. Avoid the carina if the anaesthesia is at all 'light', as the carina1 mucosa is particularly sensitive. Tracheomalacia should be observed with a small bronchoscope withdrawn from the area in question and without positive airways pressure, in order to avoid splinting. The ratio of cartilage to trachealis is significant in recording the type of malacia and if aortopexy islikely to be successful.

Typically thiscan be achieved by withdrawingthe bronchoscope to just posterior to the tip of the epiglottis. Thisaffordsagood view of the vocal cords to exclude a cordpalsy and of the arytenoidsto exclude the commonposteriorform of laryngomalacia,although anterior collapse of the epiglottis may be masked. In this case a 30" or 70" telescope should be used. If dynamic assessment is crucial, as in a suspected vocal-cord palsy, a fibre-optic bronchoscope can be passed nasally with the ET remaining in thepharynx.Theanaesthetist should call the phase of respiration to check for paradoxical vocal-cord movements.

ies

Fig. 41.7 (a) Ventilating bronchoscope and (b) telescope.

At its most challenging, removal of a long-standing organic foreign body impacted in a bronchus can tax any endoscopist. It is essential, therefore, to optimise the situationwiththe best anaesthetist available and the best equipment. Most patients are sufficiently stable for transfer to a major centre. The only acceptable 'standard of care' now is to use foreign-body extraction forceps which will accept a Storz-Hopkins telescope. The procedure is safer if the anaesthetist is able to monitor progress on a video screen, and the video is also invaluable if trainees are to learn the technique. If the foreign body is engulfed withgranulations, lignocaine 0.5% and adrenaline 1:200 000 left for 5 min prior to removal isvery helpful in maintaininga clear field. Patients

Assessment of thePaediatricAirway

291

should stay in hospital for at least 48 h postoperatively, aslate pyrexias may signal an area of collapse and consolidation.

through three separate sputum traps. The return is often quite low (20-30%). Send for microbiology (?TB)and cytology as appropriate.

Dynamic laryngosco

Laser laryngoscopy

The 'gold standard' for dynamic assessment is to insert a laryngeal mask with afibre-optic bronchoscope passed through this to just above the larynx.If a bilateralvocalcord palsy is suspected andstructuralabnormalities have been excluded with a full microlaryngoscopy and rigid bronchoscopy, the patient should be rescheduled for a further examination. A laryngeal mask and fibreoptic scope are used from the outset, reducing the influence of prolonged anaesthesia on the cord function. An alternative is to use a 30" scope, which gives a view of the larynx without splinting the supraglottis.

This is most useful for small post-intubation granulomas and for laryngeal papillomatosis. Attempts to use the laser for anterior webs or subglottic stenosis are usually unsuccessful. A laser-safe tube needs to be used and thenwithdrawnintothepharynxfor final lasering of the unintubated larynx. Great care must be takennot to damagenormal tissues and producea secondary stenosis.

Bronchial lavage

Either a rigid or a fibre-optic scope can be used. If pathology is suspected in the right upper main bronchus, a flexible scope is preferable, Wedge the end of the bronchoscope into the bronchus in question and inject 0.25ml/kg normal saline through the suction port. On thetablephysiotherapy is helpful before aspirating

Laser bronchoscopy

Modern laser bronchoscopes offer a reasonable view of lesions in the trachea and bronchi, which can then be lasered. The optics are, however, vastly inferior to normal telescopes and the technique is different. At present a 3.5rnrn scope is the smallest available. Smaller childrenwithtrachealpapillomasoftenalready have a tracheostomy and the laser bronchoscope can then be passed through this. Newer KTP laser fibres have solved some of the problems of tracheal laser therapy.

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The Oral Cavity,

Pharynx and Larynx

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Adenoidectomy and Tonsillectomy PETER M. CLARKE

Adenoidectomy and tonsillectomy are separate procedures, each with theirown specific indications. A patient should not be listed for ‘Ts and As’ unless criteria have been rigorously considered for each procedure.

Bndications Adenoidectomy

Otitis media

Otitis media with effusion, recurrent acute otitis media and nasal obstruction can all be improved by adenoidectomy (Maw & Herod,1986;Gates et al., 1988; Paradise et al., 1990). A sensible approach for both otitis media with effusion and recurrent acute otitis media is initial ventilation-tube (VT) insertion after failure of medical treatment. Adenoidectomy should be reserved for cases requiringtreatment following tube extrusion (Black et al., 1990; Paradise et al., 1990; Dempster et al., 1.993). Obstruction

The triad of snoring, mouth-breathing and hyponasal speech in children is usually caused by a combination of adenoidhypertrophy and allergic rhinitis. Adequate treatment of the rhinitis, including allergen avoidance advice, should be the first line, adenoidectomy being reserved for resistant cases. A relationship between adenoid hypertrophy and the facial skeletal characteristics of ‘adenoid facies’ has been demonstrated (Linder-Aronson, 1970), but it seems unlikely to be causal (Hibbert, 1987). Orthodonticcorrection of any malocclusion should probably be the first line of treatment.

Tonsillectomy

Recurrent acute tonsillitis

The commonest indication fortonsillectomy is recurrent acute tonsillitis. The frequency and severity of attacks have to be carefully assessed at the out-patient visit. It is also necessary to establish whether sore throats are due to true tonsillitis or mild viral pharyngitis. Tonsillitis may sensibly be considered as a sore throat lasting several days, during which the patient is systemically unwell. Parents will often not know whether a child has been pyrexial, had tonsillar erythema or exudate orhad cervical lymph-node enlargement, but these should ideally have been documented by the GP. If there is uncertainty about the severity of sore throats, the help of the GP and parents should be enlisted and the child may be reviewed aftera few months. Five or six episodes of tonsillitis in 1 year or three to four episodes per year over 2-3 years seem reasonable criteria for tonsillectomy in children. Three to four episodes a year for 2-3 years would be reasonable a indicationinadults (Hibbert, 1987; Zalzal & Cotton, 1993). Additionalfactors such astheamount of school or work missed, associated febrile convulsions or medicalconditions such asbrittle diabetes or valvular heart disease will influence the decision to undertake tonsillectomy. Quinsy

A second peritonsillar abscess is an indication for tonsillectomy, either acutely as a ‘quinsy tonsillectomy’ or 6 weeks later. If a general anaesthetic (GA) is required in a child to draina quinsy, a ‘hot tonsillectomy’ should be considered.

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Malignancy

Lymphoma may present in children as unilateral tonsillar enlargement, and so a progressively enlarging tonsil should be suitably investigated and excised. Suspicion of a squamous cell carcinoma (SCC) in an adult requires biopsy and histology. The investigation of a patient with secondary SCC in a cervical lymph node and noobvious primary source should include excisional biopsy of the ipsilateral tonsil aspart of thehuntforthehidden primary (see Lymph-node Biopsy in theHeadand Neck-Chapter 56, and Panendoscopy-Chapter 38).

investigated, and, if found, surgery should only proceed with the advice and cooperation of a haematologist. A child who has had acleft palate repaired or whohas a submucous cleft should not undergo adenoidectomy or tonsillectomy. In these patients tonsillectomy may further reduce palatal mobility, and following adenoidectomy closure of the nasopharynx may be impossible, leading to hypernasal speech and nasal reflux on swallowing.

Preoperative management

Chronic tonsillitis may be defined as a constant feeling of a sore throat associated with erythematous fauces, debris in tonsillar the crypts and enlarged jugulodigastric nodes. Chronic tonsillitis, halitosis due to debris collection in tonsillar crypts, tonsilloliths and recurrentchoking while eatingareprobably all best treated conservatively. Tonsillectomy may, however, improve symptoms in resistant cases. Tonsillectomy may be performed in adults as an integral part of uvulopalatopharyngoplasty (UPPP) and for access to the styloid process or glossopharyngeal nerve.

The decision to list apatientfor tonsillectomy relies on history, examinationadding little to the available information. Certainly tonsillar sizeis not significant and jugulodigastric nodes are often palpable in healthy children. The concept of ‘unhealthy tonsils’ is doubtful. Examination of the postnasal space is usually impossible in children of the age likely to have significantadenoid tissue. Palatal elevation may give an impression of available space in the nasopharynx and a lateral radiographmay be helpful in assessing adenoid size. It is important that parents and patientsaremade aware that surgery will not completely relieve problems but the frequency and severity of symptoms should be reduced.

Adenotonsillectomy

Relevant anatomy

Obstructive sleep apnoea

The local anatomy is outlined in Figs 42.1 and 42.2.

Other indications

Adenotonsillectomy may commonly be carried out if thereareseparateindicationsfor each. A child with recurrent acute tonsillitis, nasal obstruction and otitis media with effusion may need both adenoidectomy and tonsillectomy. Obstructive sleep apnoea, however, is a single indication for undertaking bothtonsillectomy and adenoidectomy. In children, severe obstruction of the upper airway can lead to obstructive apnoeic episodes during sleep, when respiratory effort continues but no air flow is produced. The resultant hypoxia and hypercapnoea lead to daytime somnolence andpoor concentration at school and may eventually cause pulmonary hypertension, rightheart failure anddeath (Eliaschar et al., 1980).

ontraindications Contraindications to surgery are those of any GA, including a concurrent upper respiratory tract infection. Any suspicion of a coagulation disorderneeds to be fully

Operative technique Adenoidectomy

Under GA, administered via an oral endotracheal tube (ET) or laryngeal mask (Williams & Bailey, 1993), the patient is placed supine on the operating table, with the surgeon standing at the head of the table, wearing a headlight. Overextension of the neck should be avoided, as this brings the odontoid peg and arch of theaxis anteriorly, so impinging on theposteriorpharyngeal wall. This would make damage to the prevertebral muscles more likely during the procedure. 1 A Boyle-Davis gag is inserted into the mouth, thesplit blade of the gag holding the anaesthetic tubeand tongue in the midline as the gag is opened. 2 The palate is palpated to exclude a submucous cleft and the finger can be slipped behind the soft palate to assess adenoid size. 3 An adenoid curette is inserted into the nasopharynx,

Adenoidectomy and Tonsillectomy

297

Fig. 42.1 Sagittal section showing relations of the tonsil and adenoid. The tonsil has been removed to reveal structures on its deep aspect.

I Stylopharyngeus

Fig. 42.2 Axial section at the level of the tonsil.

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Chapter 42

Fig. 42.3 Adenoidectomy. The curette is swept down the nasopharynx using the thumb as a fulcrum.

swab, the area shouldbe checked with a mirroror finger for tags of adenoid tissue, which should be recuretted. Further swabs maybe wetted with hot water or 1 :1000 adrenaline and inserted in the nasopharynx for 5min. Alternatively, a haemostatic pack, such as calcium sodium alginate (Kaltostat), may be used. Troublesome bleeding points may be visualised with a mirror and/or palate retractor and cauterised with diathermy, a silver nitrate stick or suctiondiathermy.Apostnasalpack should be used only as a last resortif bleeding cannot be controlled (Fig. 42.4). 6 At the end of the procedure, the surgeon should be certain that there is no bleeding. After extubation the patient is placed on their side, slightly head-down and transferred to the recovery area.

inferiorly towardsthetongue base. The scissors are turned round and the mucosa is incised over the top of theupper pole to prevent mucosal tearing on to the uvula during later dissection (Fig. 42.5). 4 Blunt dissection with the scissors follows the tonsil capsule laterally to create aplane between the tonsil and pharyngeal musculature. The tonsil forceps can then be repositioned with one blade in this plane, so pulling the whole of the upper tonsil medially. This medial traction should be maintained throughout the procedure. 5 Blunt dissection now proceeds with a Gwynne-Evans tonsil dissector or swab over the upper pole and down towardsthe tongue base. Care should be taken to stay in the relatively avascular plane between tonsil and muscle (see Fig. 42.2);otherwise bleeding may be increased or tonsillar tissue may be left in situ. Adult tonsils, especially after a previous quinsy, may be very adherent to the underlying muscles. In this case, dissection needs to proceed using the scissors. 6 At the junction of tonsil and tongue base, a snare is placed over the tonsil and positioned at the lower extent of dissection, to divide the tonsil from its final fibrous attachment.Alternatively, the lower pole may be clamped with a curved artery forceps and cut with scissors, leaving the forceps in place to allow a ligatureto be tied. Once the tonsil is removed, a swab is placed in the fossa and the second side is attended to. 7 With the swabin the second side, haemostasis of the first can proceed. The anterior pillar of the fauces may

Tonsillectomy

Anaesthesia is administered as for adenoidectomy, but a sandbag is placed under the shoulders, so extending the neck. The surgeon sits at the head of the table wearing a headlight. 1 A Boyle -Davis gag is inserted asforadenoidectomy. If the tongue is not held in the midline by the gag, access to onetonsil base is very difficult. The gag is then suspended, usually with a Draffin bipod. 2 The superior pole of one tonsil is held in Denis Browne tonsil-holding forceps or similar and pulled medially. 3 The mucosa is incised with scissors near the apex of the anterior faucalpillar. The incision is then continued

Fig. 42.4 The insertion of a postnasal pack. The pack has three tapes secured to it. Two soft rubber catheters are passed through the nose into the oropharynx. Two of the tapes are tied to the catheters and pulled back through the nose. The tapes are then tied firmly over a bolster or piece of tubing to protect the columella. The third tape exits via the mouth and is secured to the cheek; it is subsequently used to remove the pack.

Adenoidectomy and Tonsillectomy

299

en Postoperatively, patients who have undergone tonsillectomy or adenoidectomy should be monitored carefully with a view to early detection of any haemorrhage. This will involve regular measurements of pulse rateand observationfor excessive swallowing or anyfrank bleeding from mouth or nose. It appears safe, and will become increasingly common, to undertake day-case adenoidectomy (Sheppard et al., 1993). After tonsillectomy patients may require simple analgesia and should be encouraged to eata normal diet.

Fig. 42.5 Tonsillectomy. The mucosa of the anterior pillar of the fauces is incised down to the tonsil capsule. The incision is extended over the upper pole (arrow).

be reflected witha pillar retractorand the bleeding points visualised with a swab, using a dabbing, rather than wiping motion. The author’s preference is for bipolar diathermy, but surgeons should first become adept at ligature tying. 8 A bleeding vesselis clamped withthetip of a straightartery forceps, takingcare notto include surrounding tissue. A curved clamp is then placed under the tip of the straight clamp, which is removed, and a 2/0 linen or silk tie is placed around the curved clamp, using a Negus knot-pusher (Fig. 42.6). When tying the knot, care must be taken not to abrade the angle of the mouth. 9 Once haemostasis is complete, the postnasal space, pharynx and laryngeal inlet should be cleared of blood clot. The Boyle-Davis gag should be released and the lower poles checked again for bleeding which may have been controlled by the pressure of the gag. 10 As for adenoidectomy, absolute haemostasis should be achieved at the end of the proceduresuch that further pharyngeal suction is not needed. The patient is then placed on their side, slightly head-down, and transferred to the recovery area.

The principal complication of either operation is bleeding. This may be reactionary or secondary. Patients with post-tonsillectomy or adenoidectomy haemorrhage should have an appropriate IV line inserted and blood should be taken for full blood count, clotting studies and cross-match. Any child withaprimaryhaemorrhage lasting more than a few minutes should be returned to theatre to be reintubated by an experienced anaesthetist. If the bleeding is from the tonsillar bed, a single vessel can sometimes be found and ligated. There may be general ooze, requiring the pillars of the fauces to be sutured over some haemostaticagent, such as Surgicel. Bleeding from the adenoid bed should be dealt with as described previously. Atonsillarhaemorrhagein anadult canoften be controlled by pressure with a swab dampened with1m1

Iigatu re

Fig. 42.6 Haemostasis after tonsillectomy. A Negus pusher is used to help position and tighten the knot as shown.

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of 1:1000 adrenaline. Any clot in the tonsil fossa should first be gently sucked out or ‘shelled’ out with a small, warmed laryngeal mirror. Any patient with persistent bleeding should of course be returned to theatre.

l t e r n ~ ~ procedures i~e Both tonsillectomy and adenoidectomy have been described using the laser (Martinez & Akin, 1987). Electrocautery is commonly used in the USA (Zalzal & Cotton, 1993), anda group fromLisbon have described microsurgical bipolar tonsillectomy (Andrea, 1993). Dissection with the bipolarforceps can be helpful in the author’s experience and certainly reduces blood loss, but may be associated with some increased postoperative pain (Leach et al., 1993). An endoscopic approach to adenoidectomy has also been described (Becker et al., 1992).

Reeommendations for further reading Paradise and colleagues’ studies published in 1978 and 1984 provide interesting reading for all surgeons listing patients for tonsillectomy. Fry and Pillsbury (1987) review the indications for adenoidectomy and tonsillectomy concisely.

References Andrea M (1993) Microsurgical bipolar cautery tonsillectomy. Presented at: New Perspectives in Otolaryngology- Head and Neck Surgery, St Thomas’s Hospital, London, England, July 1993. N & Coglianese D (1992) Endoscopic Becker SP, Roberts adenoidectomy for relief of serous otitis media. Laryngoscope 102, 1379-84. Black NA, Sanderson CF, Freeland AP & Vessey MP (1990) A randomized controlled trial of surgery for glue ear. Br. Med.J . 300, 1551-6. Dempster JH, Browning GG & Gatehouse SG (1993) A randomized study of the surgical management of children with persistent otitis I. media with effusion associated withahearingimpairment. Laryngol. Otol. 107, 284-9.

Eliaschar J, Lavie l’, Halperin E, Gordon G & Alroy G (1980) Sleep apnoeic episodes as indicationsfor adenotonsillectomy. Arch. Otolaryngol. 106, 492-6. Fry TL & Pillsbury HC (1987)Implications of ‘controlled’ studies of tonsillectomy and adenoidectomy. Otolaryngol.Clin. North Am. 20,409-1 6. Gates GA, Avery CA & Prikoda TJ (1988) Effect of adenoidectomy upon children with chronic otitis media with effusion. Laryngoscope 98, 58-63. Hibbert J (1987) Tonsils and adenoids. In: Evans JNG (ed.) ScottBrown’s Otolaryngology, Vol. 6, Paediatric Otolaryngology. London, Butterworths, pp. 368-83. Leach J, Manning S & Schaefer S (1993) Comparison of two methods of tonsillectomy. Laryngoscope 103, 619-22. Linder-Aronson S (1970) Adenoids: their effect on mode of breathing and nasal air flow and their relationship to characteristics of the facial skeleton and the dentition: abiometric, rhinomanometric and cephalometric-radiographicstudy on childrenwith andwithout adenoids. Acta Otolaryngol. 69 (Suppl. 265), 1-132. Martinez SA & Akin DP (1987) Laser tonsillectomy and adenoidectomy. Otolaryngol. Clin. North Am. 20, 371-6. Maw AR & Herod F (1986) Otoscopic, impedance and audiometric findings in glue eartreated by adenoidectomy and tonsillectomy: a prospective randomized study. Lancet i, 1399-402. Paradise JL, Bluestone CD, Bachman RZ etal. (1978) History of recurrent sore throat as an indication for tonsillectomy. N. Engl. J . Med. 198,409-13. Paradise JL, Bluestone CD, Bachman RZ etal. (1984) Efficacy of tonsillectomy for recurrent throat infection in severely affected children: results of parallel randomized and nonrandomized clinical trials. N. Engl. J . Med. 310, 674-83. al. (1990) Efficacy Paradise JL, Bluestone CD, Rogers KD et of adenoidectomy for recurrent otitis media in children previously treated with tympanostomy-tube placement: results of parallel randomized and nonrandomized trials. JAMA 263, 206673. Sheppard IJ, Moir AA, Thomas RS & Narula AA (1993) Organisation of day-case adenoidectomy in themanagement of chronicotitis media with effusion-preliminary results. Journal of the Royal Society of Medicine 86, 76-8. Williams PJ & Bailey PM (1993) Comparison of the reinforced laryngeal mask airway and tracheal intubation for adenotonsillectomy. Br. J . Anesth. 70, 30-3. Zalzal GH & Cotton RT (1993) Pharyngitis and adenotonsillar disease. In: Cummings CW, Fredrickson JM, Harker LA, Krause CJ & Schuller DE (eds) Otolaryngology --Head and Neck Surgery,Vol. 2. St Louis, Mosby Year Books, pp. 1380-98.

Uvulopalatopharyngoplasty GRANTJ.E.M.BATES

Laugh and the world laughs with you; snore and you sleep alone (Anon.)

Introduction The pathophysiology of snoring and obstructive sleep apnoea

The sounds of snoring originate in the collapsible parts of the airway (between the posterior choanae and the epiglottis). Three main factors contribute to snoring and obstructive sleep apnoea (OSA). Reduction in pharyngeal muscle tone

Contraction of the pharyngeal dilator muscles (genioglossus, tensor palatini, geniohyoid and stylohyoid) occursin advance of diaphragmatic contraction. The action of these muscles keeps the airway open against thenegative pressure of inspiration. Muscle tone is reduced with sleep and if the dilator action is insufficient, airway collapse and snoring result.Alcohol, sedatives, hypothyroidism and some neurological disorders reduce muscle tone and exacerbate snoring. Presence of any space-occupying masses impinging on the airway

The classic example is the snoring and apnoea of childhood which is caused by enlarged tonsils and occasionally adenoids. However, one-third of adults also have tonsils large enough to cause airway obstruction. Bulky andobstructivepharyngeal tissues may also result from obesity. Excessive length of the soft palate

and uvulamay narrowthe nasopharyngealaperture. Retro- or micrognathia produce a relatively large tongue, while true macroglossia occurs in Down’s syndrome and acromegaly. Tumours, polyps or cysts will all narrow the airway. Restriction of nasal airflow

If the nasal resistance is increased, a higher inspiratory pressure is required and this leads to collapse in the compliant parts of the airway. Septal deviation, ostiomeatalandturbinateabnormalitiesand allergic and vasomotor rhinitis all increase nasal resistance. Definitions

Snoring

Snoring occurs because of a partially obstructed airway and the mechanism involves the Bernoulli effect. Reduced muscle tone and/or obstructingtissues narrow the airway and as a result the airflow has to increase, leading to a local fall in pressure. The pharyngeal walls are ‘sucked’ closer together and this reduces the air flow so that the pressure rises and the airway is restored. This sequencecauses vibration of thepharyngeal tissues, which results in snoring. Obstructive apnoea

Obstructiveapnoeaoccurswhenthere is noair flow despite respiratory effort. The airway has totally collapsed and eventually a mismatch between information fromthechest-wall muscles andthelungreceptors arouses the subject so that the ‘resuscitative gasp’ oc-

lking

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curs. Severely affected individuals may have apnoeic episodes lasting over 30s and these events may occur several hundred times a night. The apnoea index (AI)is the number of apnoeas occurring per hour. Hypopnoea

Hypopnoea occurs when there is a reduction in respiratory flow sufficient to cause a drop in oxygen saturation andlor an arousal. Hypopnoeas and apnoeas both cause arousals and so result in poor-quality sleep and daytime sleepinesss. The appnoea-hypopnoea index (AHI)is the number of these episodes occurring in 1h.

Medical risks

The medical risks of severe snoringprobablyequate to the risks of mild hypertension,butthe risks of OSA aresubstantial. In onestudy, men with OSA were 23 times more likely to have myocardial a infarction than matched non-apnoeic controls (Hung et al., 1990).

indications 1 IJvulopalatopharyngoplasty (IJPPP) is indicated for the treatment of heroic snoring. A heroic snorer is one

THE EPVVORTH SLEEPINESS SCALE

How likely are youto doze offor fall asleep inthe situations described in the box below, in contrastto just feelingtired?

Even if you haven't done some of these things recently try to work out how they would

have affected you.

Use the following scaleto choose the most appropriate number for each situation:

0

=

Would never doze

l = Slight chanceofdozing

I

1 1

I 1 and

1

2

=

Moderate chanceofdozing

3

=

High chanceofdozing

I

Sittingandreading Watching TV Sitting, inactive in a public place (e.g. theatre or a meeting)

As a passenger in a carfor an hour withouta break Lying downto rest in the afternoon when circumstances permit Sitting

to someone

I

I

l I I

Sitting quitely after lunch without alcohol In a car, while stopped for a few minutes in the traffic

Thank you for your cooperation

Fig. 43.1 The Epworth sleepiness scale, A score >l1is suggestive of sleep apnoea.

~v~lopalatopba~yngoplasty 303 whose partner often has to sleep in another room because of the noise. Heroic snoringresults in poor-quality sleep, and has deleterious effects on the cardiovascular system. 2 UPPP is indicated in a few individuals with OSA. In those OSA patients likely to benefit, the airway obstruction will be at the level of the oropharynx.

Preoperative History

It is important to estimate the severity of the problem; most men snorebutmost do not need a UPPP! The partner’s history is vital, as anestimate of the severity of the noise and a description of the breathing patternmay be obtained. Daytime sleepiness can be quantified with the use of aquestionnaire (Fig. 43.1).Enquire about lifestyle: exercise or the lack of it, alcohol intake and weight gain. Some individuals only snore when they are overweight. Collar size can increase because of obesity and a collar size over 17 is one of the hallmarks of sleep apnoea.

Examination

Height, weight and blood-pressure should be recorded. A careful assessment of theairwaythen needs to be made, looking particularly for factors that may cause obstruction (Fig. 43.2). Endoscopic examination of the nose may reveal inflammation or mechanical obstruction. Hypopharyngealobstruction will notrespond to UPPP and so a careful evaluation of thetongue and mandible needs to be made. Dental crowding, retrognathia and a large lingual tonsil are all associated with hypopharyngeal obstruction. A patient suitable for aUPPP will have obstruction at the level of the oropharynx. Large tonsils, a long soft palate, oedematous uvula and excessive lateral pharyngeal tissues are the hallmarksof oropharyngeal obstruction. A good candidate for a UPPP will have oropharyngeal obstruction and a larynx that is easily visible on mirror examination. Flexible nasendoscopy Thepatency of theupperairway changes withthe respiratory cycle and the best way to observe this is witha flexible endoscope. It is helpful to observe theairway attwo different levels (Fig. 43.3).With theend of theinstrumentinthenasopharynx,the closure of the soft palate can be observed (ask the patient to say ‘ng’). The amount of excess soft palate can then be judged. The Mueller manoeuvre is like a reversed Valsalva. Inspiratory effort is made against a closed mouth and nose. During the manoeuvre an attempt is made to see whether the airway collapses at the level of the palate (oropharynx) or whether the collapse is at the level of the tongue base (hypopharynx). Sleep nasendoscopy In this technique the patient is given IVsedation, preferably by an anaesthetist. Nasopharyngoscopy can then be carried out with the patient ‘asleep’, which allows a further assessment of the level of obstruction. The Mueller manoeuvre and sleep nasendoscopy may provide useful information concerning the level of collapse.

Fig. 43.2 Normal nose and pharynx on one side. Abnormalities associated with snoring on the other side: long soft palate and uvula, large tongue and lingual tonsil, large palatine tonsil and deviated nasal septum.

Sleep study

The history and examination alorie cannot confidently distinguish between heroic snorers and those who have OSA and therefore a sleep study is an essential part of

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er The principle of UPPP is to maximise thepotential oropharyngeal airspace without jeopardising the physiological functions of the soft palate (swallowing and speech). The patient is given a general anaesthetic (GA), using an oralendotracheal tube (ET).At the startof the operation, 600mg of amoxycillin and clavulinic acid are given intravenously. The patient is placed supine with a sandbag under the shoulders and a horseshoe to support the head, which is extended.The lips are greased with Vaseline and a Boyle-Davis gag is inserted. If the tonsils are present, they are removed. Meticulousattention should be paid to haemostasis of the tonsil bed, using bipolar diathermy. If the patient has already had a tonsillectomy the mucosa between the two pillars is removed. lncisio

Fig. 43.3 Fibre-optic nasendoscopy. (a) The palatal closure is viewed. (b) The tongue base and larynx are viewed.

their investigation. Thedistinction needs to be made because continuous positive airway pressure (CPAP) should be the first-line treatmentforthemajority of patients who have OSA. The sleep study also provides a preoperative objective measurement of the severity of snoring. One night in a sleep laboratory does not always provide sufficient representative information, and home recordings are useful. A noise-activated taperecorder(witha small microphone clipped to a headband) is used while the patient sleeps in hidher own bed.

Resecting the correct amountof palate is of vital importance. The attachment of the levator palatini makes a dimple in the palate that can be seen preoperatively and the resection line should be well below this dimple. The author finds preoperative nasendoscopy useful for estimating the amount of excess soft palate. In addition, in the anaesthetised patient the palate can be pushed back against the posterior pharyngeal wall (Fig. 43.4). The point of contact with the pharyngeal wall is noted and the incision is started below this. The incision is then carried from this point in a horizontal direction until it joins the anterior pillar. Part of the anterior pillar is resected but it is advisable to preserve most of the posterior pillar.

General advice and preoperative counselling

If appropriate, weight loss and alcohol reduction should be strongly recommended. Nasal obstruction should be treated either medically or surgically. If nasal surgery is required, it is best to do this first and then reassess the need for UPPP. Finally, before proceeding to UPPP, thepatient should be warned that theoperation is painful, and the potential complications discussed. The patient can then be told that the operation is usually successful, significantly reducing snoring in over 90% of patients.

Fig. 43.4 the Judging

amount of soft palate to resect.

~

Uuulopalatopba~yngoplasty 305 needle) is used and the needle should pass through the muscle layer as well as through the leading edge of the soft palate. The sutures should be cut short to avoid irritation. At the end of the procedure the anteroposterior diameter as well the as lateral dimension of the oropharyngeal airway should have been increased. An injection of 0.5% marcaine is then made slowly into the lateral margins of the soft palate and infiltrated between the tonsil pillars. A nasopharyngeal airway, trimmed so that it just hangs down behind thepalate, is then inserted.

Postoperative m ~ n a ~ e m e ~ t Control of pain

Fig. 43.5 A box-like resection.

The aim should be to produce a box-like resection (Fig. 43.5) with conservationof the middle of the palate (when resecting the soft palate it is best to err on the conservative side). The resection can be performed with a scalpel, cutting diathermy or CO,, Nd-YAG or KTP laser. The author now uses an Nd-YAG contact laser. Necessary precautions for thelaser include saline drapes around the patient’s mouth, and glasses for all theatre personnel.

UPPP is a painful procedure and a diclofenac suppository, a small dose of opiate and local anaesthetic are given during the operation. Postoperatively, a combination of effervesent diclofenac, paracetamol and local anaesthetic lozenges keeps the opiate requirements to a minimum. Starting with a soft diet, patients should be encouraged to eat and drink as soon as possible. Patients with heroic snoring without significant apnoea should be nursed on the main ward in full view of the nursing staff. Sleep-apnoea patientsshould spend at least the first postoperative night on a highdependency unit.

Resection of the palate is easier if it is held under tension. This can be accomplished by grasping the leading edge of the palate with a haemostat or by placing a suturethrough it, and then pulling itforwards.The edges of the palatal incision should be bevelled so that the excision line pointsforwards.The gag should be released intermittently to avoid prolonged tongue compression. Two small arteries are present on each side of the uvula and they canretractintothe soft tissues, which makes bipolar diathermy difficult. If necessary, clip each artery and tie with 3/0 catgut.

The posterior pillar is pulled forwards and sewn to the anterior pillar (Fig. 43.6).The incision lines should pointforward,awayfromtheposterior pharyngeal wall. A3/0chromiccatgutsuture (21mm taper-cut

Fig. 43.6 Reconstruction. Deep sutures pulling the posterior pillar forwards.

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Chapter 43

Complicati Themajority of postoperative sequelae are mild but occasionally significant morbidity and even mortality can occur (Fairbanks, 1990). 1 The immediate postoperative period can be associatedwithairway problems because of the combined effects of sedation, narcotics, muscle relaxants, oedema and haemorrhage. The author inserts a nasopharyngeal airway and keeps this in place until the patient is awake and sitting up in recovery. 2 Primary haemorrhage is rare and is managed in the same way as a tonsil bleed. Postoperative oedema and the presence of blood can make reintubation difficult and anelective tracheostomy may be necessary. Secondary haemorrhage may occur as a result of postoperative infection and usually requires antibiotics only. 3 Temporary velopharyngeal incompetence occurs in themajority of patients. Usually there is mild nasal regurgitation,particularly if thehead is flexed while drinking. Provided the patient has been warned preoperatively that this will occur, it doesnot appear to be troublesome and thesymptoms subside after 2-3 weeks. Persistent nasal regurgitation is very rare. Hypernasal speech is also manifestation a of velopharyngeal incompetence. It is an unusual complaint but occasionally fricative sounds are weak. The loss of the uvula may be associated with loss of vocal trill. Vocal trill is asound used in French, German, Greek and Spanish. It is worth enquiring preoperatively to see if your patient speaks anyof these languages. 4 Nasopharyngeal stenosis is rare a troublesome complication.Minimalposterior pillar resection and meticulous suturing seem to be the best way of avoiding it. 5 Relatively minor symptoms are common and include ‘a dry throat’ ‘food sticking’ and ‘altered taste’. Almost invariably these symptoms settle with time.

Alternative procedures Tonsillectomy alone

If the majority of the obstruction is due to large tonsils, then a tonsillectomy alone may be sufficient. Tonsillectomy also has a role in selected patients with OSA. Palatal stiffening

This is an operation devised by Peter Ellis (Ellis et al.,

Fig. 43.7 The laser-assisted uvulopalatoplasty technique.

1993). Sleep nasendoscopy is used to see if the snoringis caused by palatal flutter. In these patients a longitudinal section of mucosa is removed from the palatalsurface of thesoftpalate and a uvulectomy is performed.The scarring that is induced stiffens the whole length of the soft palate and reduces palatal vibration. The laser-assisted uvulopalatoplasty technique

This technique was devised by Dr Yves-Victor Kamami. Theprocedure is performedunder local anaesthetic with the patient sitting upright in a dental chair. A special CO, laser hand-piece with a backstopto protect the posterior pharyngeal wall is used. Vertical incisions are made through the palate on each side of the uvula (Fig. 43.7). The uvula is then shortened and reshaped.Theprocedure is usually done in one stage, although itis perfectly feasible to do a numberof similar procedures, continuing until the snoring has ceased. It has been used in patients with OSA but it will only help those who have obstruction at the level of the soft palate.

References and further reading Ellis DDM,Williams JE & Shneerson JM (1993) Surgical reliefof snoring due to palatal flutter: a preliminary report. Ann. Roy. Coll. Surg. Engl. 75, 286-90.

.

\

Fairbanks DNF(1990) Uvulopalatopharyngoplasty complications and avoidance strategies. Otolaryngol. Head Neck Surg. 102,23945. Fairbanks DNF & Fujita S (eds) (1994)Snoring and Obstructive Sleep Apnea, 2nd edn. New York, Raven Press.

~ v ~ l o p a l a t o p ~ a r y n g o p l a s t3y07 Hung J, Whitford EG, Parsons RW & Millman DR (1990) Association of sleep apnoeawith myocardial infarction in men. Lancet 336, 26 1-4. Stradling JR (1993) Handhook of Sleep-relatedBreathingDisorders. Oxford, Oxford University Press.

Surgery for Benign Lesions of the Oral Cavity ROBERT M. SUDDERICK

Introduction The oral cavity extends from the lips to the anterior pillar of the fauces. It includes the buccal mucosa, upper and lower alveolus and gingiva, floor of themouth, anterior two-thirds of the tongue and hard palate. The mouth is lined by a mucous membrane covered with stratified squamous epithelium and adherent to deeper structures, thus preventing damage by the teeth when chewing. On the lips, cheeks and tongue it is attached to the underlying musculature, and on the hard palate and alveolus to the periosteum, thus creating a mucoperiosteum. Small mucousglandsarescattered throughout the mouth, especially the lower lip. A great variety of benign lesions can be found arising from or beneath the oral mucosa. Most of these are inflammatory hyperplasias and granulomas,but it is essential that, despite their generally benign appearance, these lesions are excised and sent for histological examination. This can invariably be achieved under local anaesthesia, using a simple infiltration technique, although local blocks are used whenappropriateand general anaesthesia is usually employed for children.

Buccal, alveolar and gingival lesions Discrete lesions arising fromthe gingiva aretermed epulides and areoften an inflammatory overgrowth containing immature vascular granulation tissue (compare with pyogenic granuloma and pregnancy epulis). Conservative local excision is usually sufficient. A proprietaryperiodontal pack is oftenrequired tocontrol bleeding from the raw surface left behind and toprotect it until it has healed. Other characteristic lesions arising from the mucosa

overlying the alveolar processes are the denture granuloma(hyperplasia) usually seen in the buccal sulcus, either singly or as parallel lesions, in relation to the flange of an overextended denture and the diffuse gingival enlargements seen with certain drug treatments, e.g. phenytoin. The need to remove dentures when examining the oralcavity is dramatically illustrated by the lesion found under an upper denture, the aptly named leaf granuloma (or fibroma or fibroepithelial polyp). This sits happily concealed, flattened between the palate and denture, and yet falls into view on removal of the plate. All types of benign tumours may be found throughout the oral cavity. Papillomas arethe most common lesions, occurring equally on the cheeks, soft palate, fauces and tongue. They appear as a wart-like white or pink swelling with finger-like processes of stratified squamous epithelium, the larger ones with a vascular connective-tissue core. Dysplastic changes are very rare and simple excision is all that is required. Fibroepithelial polyps are found throughout the oral cavity (although true fibromas are rare). These pedunculated lesions are moreeasily excised by transfixing with a suture which, when placed under tension, allows easy identification of the base or pedicle, thus making removal more simple (Fig, 44.1). A special mentionshould be made of leucoplakia (literally: whitepatch),aterm which is reserved for those lesions that cannot be wiped off, where no other diagnosis can be made and which has traditionally implied malignant potential. The commonest sites lie on the buccal mucosa, gingiva and tongue. Biopsy is mandatory andclose follow-up is necessary, especially when found in the floor of mouth and lateral border of the tongue, where malignant change is morecommon.

Surgery for Benign Lesions of the Oral Cavity \

309

I

isotope’ of iodine (I23I or ?I). The second entity is median rhomboid glossitis, a smooth, ovoid, red lesion in the midline dorsum of thetongue(anterior to the circumvalate papillae and foramencaecum), which is said to represent a persistent tuberculum impar. Candida infection in such a lesion may lead to pain and a neoplastic appearance hence a biopsy is invariably performed, but it shouldbe remembered that carcinoma in this site is extremely rare. Fig. 44.1 Excision of lesions of oral mucosa.

Floor-of-mouth lesions Two important lesions found in the floor of the mouth are the dermoid cyst and the ranula.

Speckled leucoplakia, with its high malignant potential, occurs in the dyskeratoticstage, where patchyloss of the keratinised layer leads to the classic red-and-white appearance.

Lip lesions The lips are the common site for lesions of the minor salivary glands, accounting for 15% of minor salivary neoplasms (mostly in theupperlip). Excision biopsy of the lesion, togetherwiththe underlying salivary gland is mandatory,duetothe increased risk of malignancy compared with lesions of the major salivary glands. However, the commonest lesion is the mucusretention cyst or mucocele, found more in thelower lip in association with a minor salivary gland. The aetiology is invariably traumatic and the lesion appears as a firm, well-circumscribed bluish white swelling beneath the mucosa, withprominent blood-vessels frequently seen on the surface. There is often a history of repeated spontaneous rupture with therelease of a viscous liquid, followed by recurrence. Local excision of the lesion, associated gland and overlying mucosa with simple primary closure is required,but recurrence is not uncommon.

Tongue lesions Two specific lesions of the tongue occur, both of which require special mention, and which are thought to be developmental. First, the lingual thyroid presents as a nodular mass at the base of the tongue in or near the foramen caecum and usually in the midline. This lesion is far more rare than is generally thought, and is more common in women. It is important to make sure that it is not the only functioning thyroid tissue before proceeding to surgical excision. This is achieved by a thyroid scan, usually withtechnetium-99m orwithan

Dermoid cysts

These may be present at birth or appearlater, usually in adolescents or young adults. They are commonly found in the midline floor of themouth,withthe lingual frenulumindentingthesuperior surface of larger lesions. Lying superficial to the geniohyoid muscle, they may cause difficulty in mastication and speech due to elevation of thetongue base. Those lying below the mylohyoid present asa midline submental mass but may rarely be found in the submandibular region. On palpation, they are soft to firm and do not transilluminate. They are true cysts lined by squamous epithelium, the commonest epidermoid variety containing keratin and squamousmaterial and the true dermoid containing skin appendages, such as hair and sebaceous and sweat glands. Their aetiology is thought to be from epithelial cell rests left after fusion of the mandibular and hyoid arches. Simple surgical excision is all that is required. Ranulas

A ranula presents as a bluish translucent cystic swelling in the floor of the mouth, to one side of the lingual frenulum. The name ranuladerives from the Latinrana, meaning frog, because of its supposed resemblance to the underbelly of a frog. They are predominantly found in children and young adults, although no age limits exist. Two types are recognised, both arising from the sublingual salivary gland or its ducts: the simple ranula,which is confined to the floor of the mouth, and the plunging ranula,with its cervical extension through or behind the mylohyoid muscle. The plunging ranula is always a mucous extravasation cyst, with a lining of condensed connective tissue. The simple ranula may be either a small localised extravasation cyst or a

310

Chapter 44 Operative technique (excision of ranula) Preparation

Fig. 44.2 Anatomy of the floor of the mouth.

retention cyst, which has an epithelial lining. Surgery consists of removal of the sublingual gland on the affected side, together with simple enucleation or drainage of the cyst contents as appropriate. Extensive dissection of the floor of the mouth or the neck is completely unnecessary and increases the risk of complications. In cases of plunging ranula, a history of trauma is often elicited. An increased incidence of ranulaformation has been noted following translocation of thesubmandibular ducts. Bimanual palpation should always be performed to identify the possibility of a plunging ranula.

1 Local anaesthesia may be successfully used in adults, where an inferior dental (ID) nerve block (Fig. 44.3) is achieved, using a dental cartridge syringe loaded with a proprietary solution of lignocaine 2% with 1:80000 adrenaline and a disposable 35-mm-length needle. 2 Facing the patient, whose mouth is open wide, the surgeon's finger palpates the junction of the horizontal and ascending ramus of the mandible. With the syringe held in the other hand, the needle enters the mucosa at approximately the midpoint of the palpating finger tip at an angle of 45". 3 The needle is advanced until bone is felt, at which point the tip is adjacent to the lingula that guards the entrance to the inferior dental canal. Theneedle is withdrawn 1mm and 1m1of anaesthetic deposited; the remaining 1m1 is deposited during withdrawal in order to obtain lingual anaesthesia. Success is judged by numbness o f the lower lip and tongue, usually within a couple of minutes. 4 General anaesthesia is invariably required in children and a nasal endotracheal tube (ET) with adequate pharyngeal packing is employed. The patientshould be lying supine with the head supported in a head ring and with about 15" upward tilt. AMushindentalmouth prop is inserted on the contralateral side to hold the mouth open. Submucosal infiltration of local anaesthetic containing 1:80 000adrenaline helps to reduce bleeding during surgery.

Relevant anatomy (floor of mouth)

The two sublingual glands are the smallest of the main salivary glands. They lie beneath the oral mucosa, anterior to the border of the hyoglossus. Each is in contact laterally with a smoothdepression on the lingual aspect of themandible close to the midline, the sublingual fossa. Medially the lingual nerve andsubmandibular duct separate it from the genioglossus and below lies the mylohyoid. Above, the mucosa of the floor of the mouth is raised as the sublingual fold and it is here that the submandibularduct also terminates. Each gland has 10-20 excretoryducts which open directly intothe submandibular duct or separately on to the sublingual fold (Fig. 44.2).

l Fig. 44.3 Inferior dental nerve block.

\

"

Surgery f o r Benign Lesions o f the Oral Cavity *

I

z

~

*

* *

3 II

"

circle cutting needle is used and, by suturing through the intezdeatal space, brings together the lingual and buccal papillae, producing excellent healing (Fig. 44.6). Postoperative management

No special measures are necessary and thepatient is allowed to eat anddrink assoonas helshe is able. Simple oral analgesia is usually all that is required. Complications

Fig. 44.4 Incision for exision of ranula.

Incision

Damage to the lingual nerve will result in paraesthesia or anaesthesia of the floor of the mouth, the lingual gingiva and the anterior two-thirds of the tongue, as well as some loss of taste. Injury to Wbarton's duct may result in stenosis and hence sialadenitis of the submandibular gland.

An incision is made along the gingival margin on the lingual side from the first molar to the canine on the opposite side, using a no. 15 Bard-Parker (BP) detachable blade on a no. 3 BP-type scalpel handle held parallel to the long axis of the teeth (Fig. 44.4). Procedure

1 This gingival-margin incision, which divides the interdental papillae, allows a full-thickness mucoperiosteal flap to be raised lingually, using a Freer elevator, and is made easier by the thick collar of attached gingiva, which helps to prevent tearing. No sizeable blood-vessels are divided when raising a flap in this manner. 2 The elevation of the flap continues until theattachment of the mylohyoid is reached. At this point, the flap is retracted posteromedially (i.e. towards thetongue)andthe sublingual gland is identified as a bulge through the periosteum (Fig. 44.5). 3 The periosteum is incised, allowing the gland to protrude through, where, by a combination of blunt and sharp dissection, the gland is freed. Care must be taken on the medial (deep) surface, as itis here that the lingual nerve and submandibular duct lie. Blood-vessels enter the gland on its posterior and medial surfaces and are divided under direct vision after coagulation with bipolar diathermy.

Fig. 44.5 Retraction of flap in excision of ranula.

Closure

No drain is necessary, and primary closure is achieved by absorbable interrupted sutures. A 21- or 22mm half-

Fig. 44.6 Suturingthe lingual flap.

3 I 2,

Chapter 44

Alternative procedures

Otherauthors havedescribedsimple enucleation or marsupialisation, with or withoutpacking, for the treatment of ranulas butall report recurrencein a proportion of cases. It seems clear that these methodsareonly reliable in cases of a simple ranula with an epithelial lining. In the case of the more common extravasation cyst with its connective-tissue lining, incomplete enucleation andlor fistula formation is likely, and hence recurrence inevitable.

Palatal lesions A number of lesions of the palate have already been mentioned, all of which may be simply excised with local infiltration. More extensive lesions require a different approach. Such lesions include the minor salivarygland tumours and a torus palatinus.Of minor salivary tumours, 60% occur on the palate and, although the pleomorphic adenoma is the most common, there is a higher risk of malignant tumours. Several hundred palatine glands are foundover the hard andsoft palates, but they do notoccur over the palatalprocesses, i.e. anterior to a line between the first upper molars. They are usually well circumscribed and encapsulated, with excision being relatively easy. However, large defects may require closure with aflap orobturator.Toruspalatinus is found in up to20% of people, although size isextremely variable. Thereis also racial variation, withan increased incidence in mongoloid and Inuit peoples. There is a 2 :1 female predominance. The lesion probably develops at puberty and invariably presents before 30 years of age. Itprobablyrepresents an overgrowth of thepalatal processes of the maxilla, and is a true exostosis, comprising lamellae of compact bone. The torus may be a ridge along the midline of the palate or be flat, nodular or lobulated. The growth rate isvery slow and it is rarely treated unless interfering with the fitment of a dental plate.

mucous and salivary glands. A number of foramina perforate the palate. Anteriorly the nasopalatine foramen lies in the midline, posterior to the incisor teeth between the premaxilla and maxilla. The greater palatine foramen lies between the maxilla and the crest of the palatine bone, medial to the second or third molar tooth, and posterior to this the palatine bone is perforated by twoor three lesser palatineforamina.The blood supply to the palate isvia the greater palatine artery (a branch of the maxillary artery), which passes through the greater palatine canal and runs forward to enter the nasopalatine canal. Veins pass backward along the artery to the pterygoid plexus. The nerve supply is from branches of the maxillary nerve via the pterygopalatineganglion,theanteriorpalatine nerve emerging through the greater palatine foramen to supply thepalateasfarforwardasthenasopalatine foramen, from which the nasopalatinenerves emerge to supply the area behind the incisor teeth (Fig. 44.7). Operative technique (palatal lesions, including torus palatinus) Preparation

Smaller lesions, especially those aroundthe gingival margin, may be removed under local anaesthesia using simple infiltration; however, larger masses and those in the midline or posterior hard palate are excised more easily by blocking the palatine nerves by infiltration at thesite of thepalatineforamina. A dentalcartridge syringe loaded with a proprietary solutionof lignocaine 2% with 1:80000 adrenaline and a disposable 35mm

Relevant anatomy (palate)

The palate is a bony shelf enclosed on its anterior and lateralborders by thedownward-projectingalveolar processes of the maxilla. The main part is composed of the palatal processes of the maxilla, with the horizontal plate of the palatine bone posteriorly and a small anteriorcontributionfromthepremaxilla.Thewhole is covered by mucousmembrane,which is inseparable from periosteum anteriorly, whereas posteriorly the two are separated by connective tissue containing numerous

Fig. 44.7 Anatomy of the roof

of the mouth.

Surgery f o r Benign Lesions of the Oral Cavity needle is required. The nasopalatine nerves are blocked by infiltrating as they exit the nasopalatine canal,and by bending the needle it is possible to directly enter the canal. The greater palatine foramen may be found approximately medial to the second molar tooth, halfway between the gingival margin and midline of the palate, and again palpation with the needle point allows accurate localisation for the block. When excising large lesions of the palate, it is necessary preoperatively to take an impression of the upper jaw to enable the construction of a temporary acrylic plate. Postoperatively, either alone or in conjunction with soft gutta percha, this enables palatal flaps to approximate accurately and lessens the risk of haematoma formation. Incision

Themost useful incision is thepalatal gingival in thedentatepatient(alongthe alveolar crest in the edentulous). Using ano. 15 blade held parallel to the long axis of the teeth, an incision is made following the gingival margin from last molar to last molar on the opposite side. Procedure

A full-thickness mucoperiosteal flap is mobilised medially and posteriorly. Anteriorly the nasopalatine neurovascular bundle is divided by sharp dissection (usually with little bleeding), but the greater palatine vessels should be preserved in the flap (Fig. 44.8). Care

Fig. 44.8 Retraction of palatal flap to show torus palatinus.

3 I3

should be taken when elevating the flap in the midline, especially over a torus palatinus, as theflap is often very thin and easily tears. The flap is elevated only as far as is necessary to enable removal of the lesion. The torus is best removed using a drill with arosehead burr; alternatively, in large lesions a fissure burr may be used to section the lesion first. Irrigation with normal saline is used throughout the drilling and afterwards, to remove any bone debris created. Closure

The flap is replaced and suturedinterdentally,as described earlier. When a large torus has been removed, there is excess flap in the midline, and in this situation a small midline elipse is removed to allow even approximation of the flap. The previously prepared acrylic plate ensures adaptation of the flap to the underlying bone and prevents haematoma formation. Postoperative management

Otherthan ensuringproperoral hygiene by regular brushing and theuse of a chlorhexidine mouthwash,no special precautions are necessary. The acrylic plate is retained for 5 days, after which time it can be removed safely. Alternative procedures

For small midline lesions a straight incision up the centre of the palate will avoid the greater palatine arteries.

Fig. 44.9 Palatal rotation flap.

Anteriorly, the incision is made into a ‘Y’ to avoid the nasopalatine neurovascular bundle. Separately, the two flaps may then be elevatedlaterally. On replacing the flaps, excess tissueisremoved fromoneorbothto enable edge-to-edge approximation. When removing other lesions(e.g. apleomorphic adenoma),themucosaofthepalatemay need to be sacrificed. In this situation a small pack of Whitehead’s varnish onribbon gauze is placed in thedefectand sutured securely to the surrounding mucosa. After 7-10 days,thismay be removedandafreshlygranulating area will be revealed. Larger lesions may have caused a

palatal fenestration, or during the resection one may be created. In these circumstances, there are two options. First, a plate may be constructed t o act as an obturator. Second, a palatal rotation flap may be used to seal the defect (Fig. 44.9). This is a posteriorly based flap on the greater palatine artery of the opposite side. A strip of full-thickness mucoperiosteum is raised and, provided the artery is approximately central, thewidth of the flap may be up to half of thepalate. Rotating the flap causes a secondary defect, which canbe dealt with as described above.

onosurgery and aryngeal Surgery MEREDYDD HARRIES AND MURRAYMORRISON

Phonosurgery Introduction

The first part of this chapter discusses the two main phonosurgical approaches currently in use for rehabilitation of voice in a patient with a unilateral vocalfold paralysis, namely vocal-fold injection and laryngeal-framework surgery. The term ‘phonosurgery’ refers to any surgery designed primarily for theimprovement or restoration of voice (Von Leden, 1991). Itis not intended to include surgery where voice is a secondary consideration and must be distinguished from conservation laryngeal surgery, wheretheprimaryaim is to eradicate cancer and voice conservation or restoration is of secondary importance. Phonosurgery includes a wide variety of surgical techniques such as vocal-fold injection, microlaryngoscopic surgery, laryngeal framework surgery, nerve grafting and neuromuscular surgery. Microlaryngeal techniques are reviewed in the second part of this chapter and there is current debate regarding the role of nerve grafting and neuromuscular surgery in phonosurgery. Theformation of multidisciplinary voice clinics allows an academic and scientific approachto voice disorders,Completepatient assessment should now include videolaryngoscopy, stroboscopy and other laboratory measures, including laryngeal electromyography. Stroboscopy is essential in the assessment of the mucosal wave of the vocal fold, and electromyography can aid in the localisation of lesions in the vaguslsuperior laryngeallrecurrent laryngeal nerve network and identify signs of reinnervation in a paralysed vocal fold.

Vocabfold injection

Selection of material Teflon

First used in 1962, this is still the commonest material being used in the UK. Teflon is a polymer of polytetrafluoroethylene and is sold as a paste consisting of 50% glycerine. This glycerine component is absorbed in the first few weeks and its volume is partially replaced, initially by an acute inflammatory reaction and later by a localised chronicinflammatory response, which encapsulates the remaining Teflon. This is in effect a localised granuloma, but the difference in the initial volume injected and the final space-occupying lesion is unpredictable, which may cause good immediate results to deteriorate with time (Kasperbauer et al., 1993). If Teflon is incorrectly placed superficially and erosion of the overlying mucosa occurs, this can lead to granulomas on the surface of the fold, and a 36% incidence of granuloma production has been reported (Gardener & Parnes, 1991). Teflon particle sizes in the paste are sold as 50-100 pm, too large for immediate lymphatic drainage since macrophagelymphaticcutoffis 40pm. Studies on a commercial preparation of Teflon, however, have found particles of Teflon of440 pm, which must lead to the question of distal spread. A study on Teflon injection into the periurethral area has shown spread to both regional and distal organs, but,although local spread to lymph nodes and the thyroid gland has been shown with laryngeal injection (Ellis et al., 1987),no distal spreadhas yetbeen documented.

31.5

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Chapter 45

Celfoarn Initially developed as a haemostatic material, this has been used in a mixture with saline to augment the vocal fold. It is atemporarymaterial, only lasting up to 3 months, and is commonly used in conjunction with a reinnervation procedure to provide temporary improvement while neural regeneration occurs.

Pat This autogenous material has numerous advantages: it is easily harvested, readily available and does not give a foreign-body reaction(Mikaelian et al., 1991). Although it can be harvested via liposuction, this can lead to up to 30% cell destruction, with increased hypersensitivity reactions, and fat harvested through a larger incision therefore causes less tissue disruption. The fatis washed in saline, loaded into a Brunings’ syringe and injected superficially into the vocal fold.

Collagen Thisprotein is anaturalconstituent of thelamina propria of the vocal fold. Widely used in dermal augmentation, it has been popularised by Ford et al. (1992) for use in the larynx,where it becomes incorporated and even replaced by new host tissue. It has been used to augmentthe paralysed andlorscarred vocal fold by injection superficially into the vocal ligament. Problems include hypersensitivity reactions, which necessitate skin testing preoperatively, and irregularity in its mode of absorption and replacement. Selection of operative method

These may be subdivided as follows: l general anaesthesia: direct laryngoscopic method; 2 local anaesthesia; (a) direct laryngoscopic method; (b) indirect laryngoscopic method; (c) transcutaneousroutethroughthecricothyroid membrane; (d) transcutaneous route through the thyroid cartilage. General anaesthesia is thecommonestmethod in the TJK. Drawbacks include visualisation problems due to the anaesthetic tubeor some other means of ventilation, the abnormal anatomical positioning of the neck, difficulty in gaining access to the larynx in patients with cervical-spine problems or otheranatomical factors preventing direct laryngoscopy and, most significantly, lack

of patient feedback via phonation during injection. This last factor plays an essential role in deciding the amount of material to inject at the time of surgery in patients undergoing procedures under local anaesthesia. Direct laryngoscopy under local anaesthesia allows patient cooperation in order to adjust the amount of injected material, but is technically demanding, requires the use of the operating theatre and still has the head in an abnormal position. The indirect laryngoscopic technique can be carried out as an out-patient procedure and therefore does not require operating-theatre time or the frequent delay in obtaining it. This is desirable where the life expectancy of the patient is short and there is a high general anaesthetic (GA) complication risk due to the frail medical condition of the patient. Although in expert hands it is reported to give excellent results, many find the technique difficult to master. The head position is still abnormal and, due to the length of the instruments, it is difficult to assess the depth of penetration into the fold. Some needle tips have a side opening andlor ashield that prevents the tip from passing too deep, although this does not guarantee correct positioning. Transcutaneous techniques maintain the benefits of being procedures that can be carried out inthe outpatient setting and have the great advantage that the head can be placed inaneutral,moreanatomically correct, position (Hirano et al., 1990; Strasnick et al., 1991; McCaffrey, 1993). Penetratingthecricothyroid membrane is becoming a more familiar technique, now that botulinum-toxin injections into the thyroarytenoid muscle for adductor spasmodic dysphonia are increasing. The injection needle can either pass directly into the cord without entering the laryngeal lumen or pass initially into the lumen and then across into the fold while being visualised via the nasendoscope. Correct needle position is almost guaranteed when penetration is lateral through the inferior half of the thyroid cartilage, but difficulty can occur when the cartilage is ossified. There are, therefore, benefits and drawbacks for each technique and in many ways it is for the surgeon to use the technique thatworks best inhidher hands. The transcutaneous method under local anaesthesia is described below. Selection of patients

Teflon injection isused in patientswithaunilateral vocal-fold paralysis due tomalignant disease, whose life espectancy is short, i.e. those who require an immediate and short-term result.

Phonosurgery and ~ ~ c r o l a r y n g eSurgery al Method Nasendoscopiccontrol is essential for this technique and requires an assistant with a flexible fibrescope and preferably acamera and television screen. Following informed consent, the patient is positioned sitting upright in an examination chair with a headrest. Topical anaesthesia of the nose, oropharynx and larynx, using a 4 % xylocaine spray, is achieved and the skin of the neck prepared with povidone-iodine solution for asepsis. A solution of lignocaine (1%),(maximum dosage =7mg/ kg body weight) with adrenaline (1in 100 000) is infiltrated locally into the skin over the cricothyroid membrane and then adeeper injection on tothe membrane is made. A 4 % xylocaine solution is now used on a 21gauge needle to penetrate the cricothyroid membranein the midline, carefully keeping the needle close to the cricoid cartilage to avoid the cricothyroid artery (Fig. 45.1). After warning the patient, 2 4 m l of this solution is instilled into the trachea,which will make the patient coughbut will anaesthetise thesubglotticarea.A flexible nasendoscope with a video camera is then inserted by the assistant into theanaesthetised nose and an image of the larynx obtained on the television screen. A 90" smoothly curved 18-gauge needle (which is bent by the surgeon beforehand, using artery forceps) is preloaded with Teflon on a Luer-lock 5ml syringe. A plastic push-on hub will not allow enough pressure for injection, due to the density of the Teflon paste, and the use of a clear, as opposed to a Brunings', syringe allows easier estimation of the amount injected. The needle is then introduced through theskin and cricothyroid membrane in the midline, enters the subglotticlumen and can be seen on the television screen. The needle is then

Fig. 45.1 Insertion of needle for transcutaneous Teflon injection via the cricothyroid membrane.

3 I7

rotated to enter the inferior surface of the vocal fold at the level of thetip of the vocal process and placed laterally, close to the medial surface of the thyroid cartilage (Fig. 45.2a7b).Teflon can thenbe injected until the fold lies in the desired position.The needle is then withdrawn back into the subglottic lumen and the patient asked to phonate. Patient cooperation by phonation gives a clear indication of the amount of material required for good voice, and direct vision allows correct placement of the desired amount of Teflon required for glottic closure. If necessary, a second injection can be placed anteriorly, usually at the junction of the anterior and middle third of the fold, although this will vary with each individual case. When a good voice has been obtained the needle is completely removed, the entry site covered witha plaster and the nasendoscope withdrawn. The authors do not routinely use antibiotic or steroid cover, and a mild oral analgesic seems to suffice. Patients are put on strict voice rest for 48 h, to theoretically prevent Teflon extruding from theneedle tract, and advised not toeat or drink for at least 4 h until the effect of the topical anaesthetic has worn off. The patient is then kept in hospital overnight to watch for any local-

Fig. 45.2 (a) Monitoring needle-position via television screen. (b) Anatomical position of needle.

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Chapter 45

ised oedema that may cause airwaycompromise,although this is unlikely using this technique. Complications Early

These include haemorrhage, infection, airway compromise, overinjection, underinjection, incorrect placement of Teflon and acute inflammatory reaction.

Late Migration of the material, granulomaformation, absence of the mucosal wave and a non-compliant vocal fold. Laryngeal-framework surgery

Payer in 191S is credited with the first description of laryngeal-framework surgery. This hasbeen refined over many years by other surgeons, but Isshiki was thefirst to describe use of an alloplastic material (Silastic) to medialise the vocal fold, and it is his name and classification of laryngeal-framework surgery, with four types of thyroplasty, that is recognised (Isshiki et aE., 197’4).It is only the Isshiki type 1 thyroplasty-now also called ‘medialisation laryngoplasty’- that is commonly practised, although it may be combined with other modifications, as mentioned below. Selection of patients

Medialisation laryngoplasty can be performed in any patient with a unilateral vocal-cord paralysis. Waiting 12, monthsinidiopathic cases is still recommended, although, if there is severe aspiration or in exceptional cases where the vocal needs of the patient require early intervention, surgery may be carried out sooner as an alternative to repeated Gelfoam injections. The reversibility and adjustability of medialisation laryngoplasty is thereforeagreatadvantage over Teflon injection in these cases. Medialisation laryngoplasty can also be used in cases of unilateral or bilateral bowed vocal cords, caused by ageing and may be useful to correct soft-tissue defects in the vocal fold as a result of previous surgery, such as laser removal of Teflon.

local anaesthesia. An assistantwitha nasendoscope, preferably withacamera and television monitor, is required. Thepatient,withinformed consent, is placed in a supine position, with the head minimally extended on a pillow andthepatientmadecomfortableenough to tolerate this position. for approximately 45min. Sedation of the surgeon’s choice, either preoperativeoral agents or peroperative intravenous agents with monitoring, is required. The nose, pharynx and larynx are topically anaesthetised with 4% xylocaine spray and the neck prepared and drapedin a sterile manner. It is useful to use a suspension table to keep thedrapes off the patient’s face and to allow access forinsertion of a nasendoscope at a later stage. The thyroid and cricoid cartilages are palpated and marked on the skin. Local anaesthetic (LA), 1% lignocaine with adrenaline (1 in lOOOOO), is infiltrated into the wound area, around theinternal laryngeal nerve asitentersthe thyrohyoid membrane and on to the thyroid cartilage ala of the affected side. A horizontal incision, preferably in a skin crease, is made at the level of the vertical midpoint of the thyroid cartilage. This extends from2cm beyond the midline on thecontralateral side to theanteriorborder of the sternocleidomastoid on the affected side. Bipolar cautery is used to achieve haemostasis. Superior and inferior subplatysmal flaps are raised so that the upper and lower borders of the thyroid cartilage are easily palpable, and the wound is held open with a self-retaining retractor (Fig. 45.3). The sternohyoid muscles are separatedinthe midline and retracted laterally, using a Langenbeck retractor; if thisdoesnot give adequate exposure, dividing the medial half of the muscle with a cutting diathermy is recommended, with repositioning of the self-retaining retractor. Exposure is usually easier

Method

This is carried out in theoperatingtheatreunder

Fig. 45.3 Exposure of the thyroid cartilage.

Phonosurgery and ~icrolaryngealSurgery in the male due to the prominence of the thyroid cartilage; in difficult cases, adouble-pronged skin hook placed at the thyroid cartilage prominence can retract the larynx towards the contralateral side for better access. The thyrohyoid muscle is elevated from the thyroid lamina, which is exposedwith its overlying perichondrium intact. A line parallel with its inferior border at its vertical midpoint is marked across the surface of the thyroid cartilage and, using callipers, a point is marked 7mrn (female) or 9 mm (male) posterior to the midline. Avoid the superior half of the cartilage, as placing an implant here will displace the false cords and supraglottic structures rather than the true cords. Using callipers, a window is marked out from this reference point of the dimensions 10 X 4 mm (female) or 12 X 5 mm (male) (Fig. 45.4). If the cartilage is not ossified, it is possible to cut out this window using a scalpel, but this is unusual and most require a drill, using a 1mm side-cutting burr for the margins and a large polishing burr toremove the cartilage. Preserving the cartilage island was originally described but has caused complications with its later displacement, and it is preferable to remove it completely. Using magnification for this procedure, either loupes or the microscope, is recommended. It is important tokeep the inner perichondrium intact so that the implant will be lateral to the body of the vocal fold, as opposed to Teflon, which sits in themuscle. This explains theloss of mucosal wave seen following the use of Teflon but its preservation with this procedure (Gardener & Parnes, 1991). The cartilage is thinnest anteriorly and superiorly, so that itis easier to drill posteroinferiorly; once an opening in the cartilage is present in thisarea,the perichondrium can be depressed with an annularcurette

to.keep it awayfromthe drill, thus decreasing the chance of perforation. At the anteroinferior corner there is often a vessel, which can bleed into the cord, making voice assessment difficult and occasionally leading to the procedure having to be abandoned. Adrenaline-soaked patties and bipolar cautery may control this. Following removal of the cartilage plate, theperichondrium is elevated, using the annular curette and then a curved Freers elevator, but only a few millimetres’ dissection is required anteriorly, where there is thin perichondrium. Now is the time for insertion of the nasendoscope so that an image of the larynx is seen on the television screen. The patient is now asked to phonate and the elevator used to displace the cord medially until the best result for closure and voice is obtained. The depth of medial displacement can then be measured and the correctly sized Silastic implant inserted. To save operating time a selection of implants previously cutshould be present, buttheimplantcan be trimmed at this time for fine individual adjustment. These are cut from a soft Silastic block, using a scalpel and to the dimensions shown in Figs 45.5 and 45.6.

Fig. 45.5 Dimensions of starting block.

Fig. 45.4 Position and dimensions of cartilage window.

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Fig. 45.6 Modifications to produce correctly sized implant.

Fig. 45.7 Sequence of inserting implant.

They should beof varying depth (3-6mm), with two superiormethod to Teflon injection, certainly in the partial parallelincisions so that it can be folded to ease long term, is increasing (Sasaki et al., 1990). Whether iGsertion. Put the posterior flange in first and, holding this gives a goodresult in patients with lateralised a cord thisinpositionwithatoothed forceps, theanterior inasuperior plane is still debatable, and many now portion is bent forward and with steady gentle pressure combine it with an arytenoid adduction procedure for snapped into position (Figs 45.7). To ensure that the closure of the posterior commisure (Netterville et al., i&plant is sitting correctly, it is useful to run around the 1993). edges of the window with the annular curette and, when Two kits for medialisation laryngoplasty are currently cdnfident of its correct placement and that it is the being developed. appropriate size, the nasendoscope is removed. The 1 The first uses a preformed plastic implant (eight availstrap muscles and ,platysma1 flaps areapproximated able sizes) withalateral flange that allowsit to be with 3J0 Vicryl and the skin closed with4/0 nylon inserted easily and tolock into position. Itcomes with a sutures. A drain is not routinely used unless there has templateformarkingthewindow dimensions and a been excessive haemorrhage. A plastic spray dressing is measuring device for the depthof implant required. The applied to the wound, which is left uncovered. If there design of the implant is said to give a better chance of has been perforation of the perichondrium, antibiotics closing the posterior commissure (Montgomery et al., ‘are added, but otherwisedo notuse steroids or antibiot1993). ics routinely. The patient is kept on the ward for 24 in h 2 The second also comes with a measuring device, a window template and preformed implants of different case of anyairway compromise, but does not require sizes which are made of hydroxylapatite and require a any voice rest and a mild oral analgesic is sufficient. At shim to be fitted into the windowof the thyroid cartilage 1 week the sutures are removed and the position of the to keep them in position (Flint & Cummings, 1993). It cord noted at laryngoscopy. is likely to be expensive and, as this is a biointegratable material and studies have shown evidence of Complications osteoneogenesis on the inner plate of the cartilage, it is unlikely to be reversible. Early .

I.

”

Haemorrhage, haematoma, infection, undercorrection, overcorrection, airway compromise due to oedema or too large an implant.

Late Extrusion or displacement of implant. Alternative techniques and developments

Evidence supporting rnedialisation laryngoplasty asa

Microlaryngeal surgery The second part of this chapter deals with the surgery of benign disease of the adult larynx,leaving conservation surgery for laryngeal malignancy to other chapters. Althoughtherehas recently been an. increase in the amount of laryngeal surgery carried out via an indirect methodunder local anaesthesia,theauthors prefer a direct method, using suspension microlaryngoscopy under general anaesthesia with either a cuffed endotracheal tube (ET) or jet ventilation. Micro-

laryngoscopy has the following advantages over‘indirect laryngoscopy: 1 binocular vision; 2 magnification; 3 ability to use both hands for instrumentation; 4 ability to use carbondioxide(CO,) laser-beam surgery; 5 protection of the distal airway via a cuffed tube; 6 controlled surgical conditions with no patient movement, thus allowing millimetres of precision. Microlaryngoscopy concentrates mainly on the glottic area in cases where the diagnosis is already established and, unlike direct laryngoscopy, is not primarily concerned withotherareas of thepharynxandlarynx, which should have been assessed preoperatively. Surgical principles There are important principles to adhere to in suspension microlaryngoscopic surgery. 1 A knowledge of the anatomy of the larynx, specifically the microarchitecture of the vocal folds and location of the pathology, is essential. The layered structure of the vocal fold (Hirano,1977) (Fig. 45.8) and its different mechanical and physical properties allow the superficial layer to oscillate independently for phonation. This coverlbody theory explains the vibratory dynamics of the mucosal wave seen on stroboscopy (Hirano & Kakita, 1985). Poor lymphatic drainage of Reinke’s space predisposes this layer to collect tissue fluid. 2 Pre- and postoperative analysis is importantand should always include stroboscopy, as the specific concern is preservation of the mucosal wave of the vocal folds, which can only be assessed this way. Pathology, such as intracordal cysts or nodules, may be difficult to diagnose with white light and their true character only becomes visible on stroboscopy. Some authors divide

lesions intohardand soft lesions, based on their preoperativeevaluationwithstroboscopy, suggesting that soft lesions are more amenable to cure with voice therapy, which again highlights theimportance of stroboscopy (Ross et al., 1993).Postoperative recording of the mucosal wave will show how much scarring has occurred between the superficial epithelium and the underlying ligament and muscle, and there is a direct relationship between preservation of this mucosal wave and quality of voice. An academic approachshouldalso utilise acoustic parameters for objective pre- and postsurgery analysis. 3 Properinstrumentation,witharange of laryngoscopes and microinstruments, is required. Exposure can be difficult and using a selection of endoscopes with a wider proximal end and distal illumination will usually allowadequate access. Instruments need to be fine, sharp and well maintained to allow precise removal of the lesion with minimal scarring. Wrenching and tearing of the mucosa leads to excessive scarring. Benign disease is usually located in the mucosal layer or in the superficial part of the intermediate layer (Reinke’s space). Surgery should therefore be superficial, staying out of the vocal ligament, with limited mucosal excision only. There is currently no role for stripping ofthe mucosa of the vocal fold for benign disease. 4 The underlying cause of the lesion must be ascertained; a multitudeof factors, such as smoking, alcohol, voice abuse (both speaking and singing), gastrooesophageal reflux and muscle misuse, should be assessed and a reasonable trialof therapy for these factors attempted. Conservative treatment with medication and expert voice therapy or postural adjustment can often promote the healing of benign mucosal disease without resorting to surgery (Bastien, 1993). It is also important that these measures should be continued postoperatively to prevent recurrence, as surgery can often temporarily remove the pathological lesion without addressing the underlying aetiology. 5 Laser versus microsurgical instrumentation? This is, to anextent, a matterof personal choice but the authors prefer to limit laser use to vascular lesions or those that may bleed on removal, such aspapillomatosis or granulomas, to the removal of cartilage and when excising large areas of tissue. The laser is not merely a precise surgical knife and the surgeon musthave an understanding of the effects of spot size, wattage and mode (pulsed or continuous) and theirsoft-tissue interaction and, importantly, the hazards linked to its use. Patient selection

Fig. 45.8 Layered structure of the vocal fold.

Microlaryngoscopycan be used foranypatientwith

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symptomatic benign mucosal lesions, provided the aetiology and other contributing factors have been assessed and a period of appropriate therapy given. Surgical method

After intubation with a small oral cuffed ET, the vocal folds are sprayed with topical anaesthetic. The tube is secured in position on the left side of the mouth andthe patient’s neck flexed and the head extended. Protecting the upper teeth with a mouth-guard, the laryngoscope is inserted via the right side of the mouth and under the epiglottis. Onceagood viewis obtained,the laryngoscope is attached to its suspension arm andfixed in position. This usually gives adequate exposure, but firm downward pressure on the thyroid cartilage may provide a better view, especially for lesions of the anterior commissure area. An operating microscope with a 350 or 400mm lens aids precision, and small neurosurgical patties soaked in topical vasoconstrictor areuseful during dissection of the vocal fold. If the CO, laser is being used, jet-ventilation anaesthesia may be used and essential safety precautions must be adhered to, including eye protectionforbothpatient and operatingtheatre personnel, wet drapes around the patient’s face and lips and, if present, ET protection. Nodules

These are bilateral lesions of functional aetiology and they usually respond to voice therapy. They are found at the midpoint of the vocal folds and are confined to the superficial squamous epithelium and underlying Reinke’s space. The centre of the nodule is held with grasping forceps (not cupped forceps, which are cutting forceps) and pulled medially towards the opposite cord. Microscissors are then used to cut the mucosa close to its base, thus preserving normalmucosa, keeping a straight vibratory edge and preventing secondary notching. Theoppositenodulecanthen be removed ina similar fashion, taking care not to damage the mucosa of the anterior commissure. There is no contraindication to removing both nodules at the same operation, using this precision technique. A microweb has been reported to be present in up to 22% of patients with nodules, and this can be divided, as can any other thin anterior web, with an arrowknife, using a specifically designed vocalfold spreadinginstrument to place the tissue under tension (Bouchayer & Cornut, 1991) (Fig. 45.9). Postoperative voice rest for 48 h is recommended, but correct technique of voice production is essential to prevent recurrence.

Fig. 45.9 Location of nodules and an associated microweb.

Polyps

These are usually unilateral, localised areas of oedematous tissue, although some may be angiomatous and containareas of haemorrhage. The site of pathology is again superficial to the vocal ligament, and careful examination may showacontact response onthe contralateral vocal fold. Gentle, steady traction is applied via grasping forceps toward the opposite cord and the base of the polyp cut with microscissors. Preservation of mucosa is essential, too little resulting in reformation of the polyp, too much resection giving a notched, scarred cord with tethering of the layers of the vocal fold. Voice rest for 48 h is recommended, as is correction of any predisposing factors. Reinke’s oedema

This is abilateral diffuse conditionwherethere is a collection of polypoidal tissue in the superficial part of the intermediate layer of both cords. A cordotomy incision is made on the lateral aspect of the superior surface of the vocal fold with an arrow-headed knife (Fig. 45.10). The median vibrating edge of the vocal fold is therefore preserved. The mucosa is then elevated with a blunt dissector and the myxomatous contents either aspirated or removed with cupped forceps (Fig. 45.11). Care must be taken to avoid damaging the vocal ligament or traumatising the overlying mucosa with excess suction.

Phonosurgery and ~ ~ c r o l a r y n g eSurgery al

3 23

Fig. 45.10 (a) Endoscopic view of superior cordotomy incision. (b)Coronal section through vocal fold showing placement of incision.

Fig. 45.11 Elevation of mucosa and removal of myxomatous contents.

Fig. 45.12 Trimming of redundant nwcosa and primary closure of the ‘wound’.

Following removal of the contents, themucosal flap is replaced and any excess epithelium trimmedwith microscissors (Fig. 45.12). There is an increasing trend to use fibrin glue or microspot laser to maintain this flap in position, but these require specific equipment that is expensive and may not give superior results over simply laying the flap in its new position. Providing care is taken in the region of the anterior commissure, there is no contraindication to operating on both folds at the same time. Voice rest and attention tounderlying causes are again essential.

nosis. The cyst is located submucosally and is best approached via a lateral cordotomyon its superior surface. Blunt dissection along the surgical planes releases the overlying mucosa and the vocal ligament beneath (Fig. 45.13). Microscissors are used to release the cyst anteriorly and posteriorly and the cavity is cleaned witha neuropattie soaked in topical vasoconstrictor to check for any remaining cyst wall, which can be compared to cholesteatoma in the middle ear. Fibrin glue or welding microspot laser may be used to replace the mucosal flap.

Intracordal cysts

These may be mucosal retention or epidermoid cysts, and stroboscopy has greatly increased the ease of diag-

Papillomas

Unlike paediatric papillomas, adult lesions tend to be

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Chapter 45 self-limiting process that ‘burns itself out’whenthe arytenoid cartilagescleroses (Benjamin & Roche, 1993). The endoscope may be set to give a better view of the posterior commissure, and thegranuloma is grasped and pulled anteromedially to expose its attachment to the arytenoid. The CO, laser (6W, 0.8 mm, 0.1 S pulsed) is used to remove the lesion flush withthe perichondrium. The patient is placed on a strict antireflux protocol, together with intensive voice therapy. Arytenoidectomy

Fig. 45.13 Exposure of cyst via superior cordotomy incision.

less florid, specifically found at areas of constriction in the upper aerodigestive tract, where there is increased air turbulence, dryingand cooling of mucosa, and at the change of ciliary to squamous epithelium (Haskins et aE., 1993). The humanpapillomavirus is the underlying cause, and CO, laser excision is the treatment of choice, with minimal trauma to surrounding tissue that may contain dormant virus. An endoscopewitha smokeevacuation channel is useful. Settings of 4 W on pulsed laser (0.1S ) with a spot size of 0.3 mm are used and, as viral particles have been identified in the smoke plume, specific laser masks for protection are available. Single papillomata are grasped gently, as they may be friable, and the laser is used to excise the base. Multiple lesions are approached in a similar manner, lasering peripherally first to deliniate the lesion and prevent trauma to surrounding tissue.

Patientswith bilateral vocal-cord paralysis withthe cords lying in a midline position compromising the airway are candidates forthis procedure. Most will already A balance between have atracheostomyinposition. obtaining a good airway and producing a good voice is difficult and this must be explained to thepatient preoperatively. Using the CO, laser (6W, 0.8 mm, 0.1 S pulsed), an incision is made at the level of the tip of the vocal process of thearytenoid cartilage on one side, completely dividing the thyroarytenoid muscle. A second linear incision is then made at the lateral border of the released vocal fold through the mucosa only (Fig. 45.14). As this incision heals, it will retract the vocal fold laterally, thus improving theairway. The vocal process is now excised, using the CO, laser (low, 0.6mm, continuous), withregular suctioning to remove the char that accumulates, and an adequate airway is obtained (Fig. 45.15). Postoperative care

Following any of the abovemicrosurgery, the endoscope

Granulomas These are located on the vocal process of the arytenoid cartilage andare unilateral, sessile, bilobed lesions. Aetiology includes endotracheal-intubation trauma, gastro-oesophageal reflux and hyperfunctional voice disorders. Granulomas frequently recur and a combination of surgery to confirm histological diagnosis, togetherwithpostoperative gastro-oesophageal-reflux treatment, injection of steroidsinto the base, oral prostaglandins, speech therapy,osteopathyfor neck manipulation and even botulinum-toxin injection into the cord to prevent movement, has been tried. Surgery alone is unlikely to cure the granuloma, and medical/ behavioural treatment is proving to be the most efficient treatment. A recent paper states that a granuloma is a

Fig. 45.14 Order of initial laser incisions for partial arytenoidectomy.

PhonosurgeryandMicrolaryngealSurgery ‘

Fig. 45.15 Vocal process of arytenoid removed.

is released from its suspending apparatusand withdrawn from the right side of the mouth, taking care not to dislodge theanaesthetictube.Thetooth-guard is removed and the teethchecked for damageor loosening. Any trauma to the soft tissues of the mouth, lips or pharynx is also noted and the surgeon should remain in the operating room until the patient is extubated andthe anaesthetist satisfied with the patient’s airway.

References Bastien R (1993) Benign mucosal and saccular disorders: benign laryngeal tumors. In: Cummings C (ed.)Otolaryngology, Head and Neck Surgery, Vol. 3, 2nd edn. St Louis, CV Mosby, pp. 1897-924. Benjamin B & Roche J (1993) Vocal granuloma, including sclerosis of the arytenoid cartilage: radiographic findings. Ann. Otol. Rhinol. Laryngol. 102, 756-60. Bouchayer M & Cornut G (1991) Instrumental microscopy of benign lesions of the vocal folds. In: Ford C & Bless D (eds)Phonosurgery: AssessmentandSurgicalManagementofVoiceDisorders. New York, Raven Press, pp. 143-65. Ellis J, McCaffery T, Destano L & Rieman H (1987) Migration of Teflon after vocal cord injection. Otolaryngol. Head Neck Surg.96, 63-6. Flint P & Cummings C (1993) Phonosurgical procedures. In:

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f

Cummings C*(ed.)Otolaryngology, Head and Neck Surgery, Vol. 3, 2nd edn:’St Louis, CV Mosby, pp. 2072-109. Ford C, Bless D & Loftus J (1992) Role of collagen in the treatment of glottic insufficiency: a study of 119 patients. Ann. Otol. Rhinol. Laryngol. 101, 237-47. Gardener G & Parnes S (1991) Status of the mucosal wave post vocal cord injection versus thyroplasty. J Voice 5, 64-73. Haskins H,Mounts P, Leventhal B & Hruban R (1993) Sites of predilection in recurrentrespiratory papillomatosis. Ann. Otol. Rhinol. Laryngol. 102, 580-3. Hirano M (1977) Structure of the vocal fold in normal and diseased states: anatomical and physical studies. In: Ludlow C & Hart M (eds) Proceedings of the Conference on the Assessment of Vocal Pathology. Bethesda, American Speech-Language-Hearing Association, pp. 11-30. Hirano M & Kakita Y (1985) Cover-body theory of vocal fold vibration. In: Daniloff R (ed:) Speech Science. San Diego, College Hill Press, pp. 1-46. Hirano M, Tanaka S, Tanaka Y & Hibi S (1990) Transcutaneous intrafold injection forunilateral vocal fold paralysis: functional results. Ann. Otol. Rhinol. Laryngol. 99, 142-8, Isshiki N, Morita H, Okamura H & Hiramoto M (1974) Thyroplasty as a new phonosurgical technique. Acta Otolaryngol. 78,451-7. Kasperbauer J, Slavit D & Maragos N (1993) Teflon granulomas and overinjection of Teflon: therapeutic a challenge forthe otorhinolaryngologist. Ann. Otol. Rhinol. Laryngol. 102, 748-51. McCaffrey T (1993) Transcutaneous Teflon injection for vocal cord paralysis. Otolaryngol. Head Neck Surg. 109, 54-9. Mikaelian D, Lowry L & Sataloff R (1991) Lipoinjection for unilateral vocal cord paralysis. Laryngoscope 101, 465-8. Montgomery W, Blaugrund S & Varvares M (1993) Thyroplasty: a new approach. Ann. Otol. Rhinol. Laryngol. 102, 571-9. Netterville J, Stone R & Luken E (1993) Silastic medialisation and arytenoid adduction: the Vanderbilt experience. Ann. Otol. Rhinol. Laryngol. 102, 413-24. Ross J, Izdebski K & Hilsinger R, Jr(1993) Efficacy of surgical treatment of primary vs. secondary benign lesions of the free vocal edge. In: Proceedings of the 6th Annual Pacific Voice Conference, San Francisco, California, 2 993. Sasaki C, Leder S, Pectu L & Friedman C (1990) Longitudinal voice quality changes following Isshiki thyroplasty type 1: the Yale experience. Laryngoscope 101, 849-52. Strasnick B, Berke G & Ward P (1991) Transcutaneous Teflon injection for unilateral vocal cord paralysis: an update. Laryngoscope 101, 785-7. Von Leden H (1991) Thehistory of phonosurgery. In: Ford C & Bless D(eds) Phonosurgery:AssessmentandSurgicalManagement of Voice Disorders. New York, Raven Press, pp. 3-23.

Tracheostomy VICTOR ABDULLAH

Tracheostomy, derived from two Greek words, ‘traxus’ meaning roughand ‘stoma’ meaning mouth(Rosas Meneses & Betancourt Landeros, 1970), is one of the oldest operations in surgery. Egyptian engravings dating back to 3600 BC included fascinating records of this procedureinancient times (Shehata, 1981). The first knowntracheostomy was performed by Asclepiades of Bithynia, a Greek physician (128-56 BC), who performedtheoperation in Rome at theCentrefor Croupous Diseases of theLarynx. George Martin,a Scottish physician, wasthe first to performa tracheostomy in England for a case of diphtheria in 1730 (Stell, 1973). It was, however, to the credit of Chevalier Jackson that tracheostomy became standardised a procedure at the beginning of twentieth the century (Jackson, 1909). Thethought of a ‘tracheostomy’ oftenimpartsa certain amount of fear and hesitation to surgeons less familiar with the procedure. Yet many non-surgical intensive-care physicians are highly skilled minitracheostomists, which leaves little room for even the mostjunior surgical trainee to shy awayfrom mastering this procedure. With the availability of quality tracheostomy tubes and aftercare in most surgical units, a properly performed and managed tracheostomy is associated with minimal morbidity.

lndications The foremost indication for a tracheostomy is Moser’s dictum ‘when a surgeon thinks about it’. This simple statementshould be treasured and will help solve many problems. Thepathologicalindicationsfora tracheostomy may be summarised as follows:

Upper airway obstruction, real or anticipated

Thiscan be congenital, acquired or part of amajor head-and-neck procedure. Pulmonary ventilation

Tracheostomy allows effective medium- to long-term intermittent positive or assisted airway ventilation. A tracheostomy should be performed in a patient still requiring ventilation through an endotracheal tube (ET) extending beyond 1 week. Pulmonary toilet

A tracheostomy provides a port for effective pulmonary toilet. The properly supervised use of a low-pressure, high-volume cuffed tracheostomytube provides only temporary control of pulmonary aspiration and is no substituteforformalairway diversion proceduresin selected cases of chronic aspiration (Eibling, 1992).

Relevant anatomy (Fig. 46.1) The trachea lies in the midline of the neck, extending from the cricoid cartilage superiorly (C6) to the sternal notch inferiorly, then passing retrosternally to the tracheal bifurcation at the level of the sternal angle (T.5).It comprises 16-20 C-shaped cartilage rings separated by fibrous tissue. The incompressible complete cartilage ring of the cricoid is a valuable landmark,andthe palpable tracheal rings allow easy identification of the trachea at surgery. Posteriorly, the circumference is completed by the trachealis muscle. The lumen is lined

Tracheostomy

3 27

Fig. 46.1 Anatomical relations of the trachea.

by respiratory ciliated epithelium, and the external surface is covered by pre-tracheal fascia. The trachea is 1012cm long and 15-20 mm in diameter in theadult, being smaller in females and adolescents. The cervical length may be-increased at tracheostomy by extending the neck and head.

artery laying more deeply, and both may be at risk, alongwiththe inferior thyroid veins, if dissection is carried too far inferiorly withinadequateexposure. Similarly, the apexof the pleura ascends into theneck in infants and small children and may be vulnerable during tracheostomy.

Relatiions

Elective tracheost

Superficially, the thyroid isthmuscovers rings two, three and four, with the lobes of the thyroid overlaying the trachea inferiorly for another one to two rings. More superficially are the strap muscles, deep and superficial fasciae, anterior jugular veins (AJVs), platysma, subcutaneous tisue and skin. The recurrent laryngeal nerves lie in the tracheo-oesophageal grooves bilaterally, with the common carotid and internal jugular vein (IJV) running parallel to the trachea more laterally. Deep to the trachea are the cervical oesophagus, pre-vertebral fascia and the vertebral bodies. Inferiorly, the brachiocephalic vein crosses the trachea obliquely, with the innominate

An elective tracheostomy can be performed under local or general anaesthesia. The operating theatre is the safest and most comfortable place in which to perform a tracheostomy and thereshould always be time, with adequate resuscitative support, to transporta patient to the operating room. If one elects to fashion a tracheostomy by the bedside on the ward or in the intensive care unit, one should expect the level and promptness of the assistance to be suboptimal. A certain amount of experience with the procedure is recommended prior to such an undertaking. Most ward beds are much wider than the operating

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table and it is wise to move thepatient to the edge of the bed to save bending over. A headlight is recommended for this procedure outside the operating room. A diathermy machine should be connected and ready for use. The patient ought to have at least a pulse oximeter connected for monitoring.The surgeon should check that all the instruments he/she requires are available and laid out in the correct sequence for the procedure. These few points can save the surgeon a lot of frustration during a bedside tracheostomy. Positioning the patient

The patient is placed supine with shoulders supported and thehead tilted backwards on a head ring. This position brings the trachea to the surface of the neck and stretches the neck skin taut, If neck extension is not possible, thesurgeonhas to rely on pre- and intraoperative palpation and direct manipulation of the laryngotracheal skeleton during the operation. Palpatbn of the anatomy (Fig. 46.2)

The laryngotracheal skeleton should be palpated carefully. Locate the thyroid cartilage, the thyroid eminence and thenthemoreprominent cricoid ring. The individual tracheal rings can then be palpated. Procedure

The incision

1 A horizontal incision is recommended for an elective tracheostomy as the resultantscar with or without revi-

sion is usually cosmetically more acceptable than the blemish after an equally long vertical scar. Nevertheless, in an emergency situation,when cosmesis takes low priority, a long vertical incision provides the shortest route with the least bleeding to the trachea. 2 The best position for the tracheostomy is at the level of the third and fourth tracheal rings, well away from the cricoid. If the tracheal rings are not palpable, the incision can be placed halfway between the cricoid cartilage and the jugular notch and the rings located intraoperatively. 3 In the case of a short fat neck, place the incision 1cm above the medial ends of the clavicles in order to avoid the flanges of the tracheostomy tube abutting on them and then establish the anatomy of the tracheal skeleton intraoperatively. The development of skin flaps and tissue planes

The incision does not need to extend beyond the anterior borders of the sternocleidomastoid muscles. Incise the skin and stroke the platysma1 layer with the scalpel to separate its fibres (Fig. 46.3). Thesubplatysmal planes are developed withthe scalpel or scissors above and below, with the help of skin hooks and countertraction with a finger and swab. The AJVs can usually be swept away quite easily from the undersurface of the platysma. The raising of skin flaps allows adequate exposure of the surgical field and creates space for the comfortable insertion of retractors for the remaining procedure. A self-retaining retractor can be used to hold the skin flaps apart. Division of the anterior jugular veins and the separation of the strap muscles

The AJVs are best divided between clamps and tied. They can be cauterised if they are small or left undis-

Fig. 46.2 Palpation of anatomy.

Fig. 46.3 Raising of skin flaps.

Tracheostomy turbed and retracted away from the midline if they are wide apart. Blunt dissection is recommended forthe opening of the midline plane. As the fascial fibres are spread apart, they are retracted with small Langenbeck retractors, which will, in addition, draw the strap muscles apart.Duringthe dissection, thesurgeonshould palpate for the trachea intermittentlyso that the correct midline course is maintained. This dissection brings the surgeon to the anterior trachealwall and the isthmus of the thyroid (Fig. 46.4). Division of the thyroid isthmus

This is best done between clamps. If the isthmus is long, more than one clamp can be applied on each side and the division can be done from top to bottom in short segments in the midline. Care should be taken at the lower end to avoid injury to thesubmanubrialbrachiocephalic vessels. The stump on each side after division should be transfixed and firmly tied (Fig. 46.5). Sometimes the isthmusis tiny and may be well out of the way of the third and fourth tracheal rings. This can be safely left but it is best not tomobilise an isthmus if one does not plan to divide it.

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the trachea (Fig. 46.6)

Prior to entering the trachea, the surgeon should check that theappropriate-sizetracheostomytubewith an inflatable cuff is available for insertion. The anaesthetist should be informed.Thetracheacan be entered in different ways- a midline slit, a cruciate incision, a windowor asuperiorly or inferiorly based (Bjork) flap-each having its advocates. The author favours the fashioning of a small window. The window spans two tracheal rings in length and approximately one-third of theanteriortracheal wall inwidth.Mostsurgeons would agree that the best level to enter the trachea is at the third and fourth tracheal rings. A size 15 blade is plunged through themucosa between the fourth and the fifth ring. The cutting edge of the blade is then turned upwards to cut through the fourth and the third rings. The blade is then taken through themucosa between the third and the second tracheal rings horizontally. A pair of toothed forceps isused to firmly gripthe piece of partially excised trachea and its excision is then completed. Insertion of the tracheostomy tube (Fig. 46.7’)

The anaesthetic tube is now withdrawn to a level just above the window. At this point the secretions in the tracheobronchial tree shouldbe aspirated with a suction catheter. The right-handed surgeon should now insert the tipof a tracheal dilator into the window with left the hand. As it is opened, gentle superior traction brings the trachea to the surface and the lubricated tracheostomy tube can be inserted from the side and gently rotated into the trachea. The anaesthetic circuit is nowconnected to the tube andthe cuff is inflated sufficiently to obtain a seal. Fig. 46.4 Exposure of the thyroid isthmus.

Fig. 46.5 Transfixion of the thyroid isthmus.

Fig. 46.6 Entering the trachea.

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Fig. 46.7 Insertion of the tracheostomy tube.

Suturing the wound and securing the tracheostomy tube

The wound can be sutured on the two sides butthe centre should be left loose around the tube to avoid surgical emphysema. A paraffin gauze dressing is placed around the tube, which serves well to keep the wound clean. The tube flanges can then be sutured with a 2/0 silk stitch to big bites of skin on both sides. The tube should then be further secured with tapes on each side withthe patient’s head flexed to avoid slack. Secure knots should be used as these tapes can always be cut and replaced. With these simple measures, a dislodged tube in the early postoperative period can be effectively prevented. The tracheostomy tract is well formed by 72h and a tube change can be performed safely and comfortably after this time.

Tracheostomy under local anaesthesia A tracheostomycan be safely performed under local anaesthesia, although thisis best done by a surgeon with some experience of the procedure. The skin and the subcutaneous tissue are the painful layers and require infiltration with 1 or 2% lignocaine. Fascial tissue and thethyroidisthmusare relatively painless and do not require infiltration. It is best not to infiltrate the trachea until it is ready to be opened, when a few drops of 4% lignocaine can be instilled. The patient must fully understand the procedure and the surgeon should remember that the patient is awake and ensure that a calm atmosphere is maintained.

Emergency tracheostomy This procedure should not be regarded as a rushed job

Fig. 46.8 Controlled longitudinal incision for a n emergency tracheostomy.

in a crisis. It should be a controlled operation, calmly conducted, in which every stroke of theoperator is purposeful, progressing to thetrachea in thecorrect direction. A long midline incision is recommended to allow the quickest and the best possible exposure with the least amount of haemorrhage. The surgeon should be encouraged that with every controlledstrokethe patient is brought closer to safety. The patient should be positioned correctly as for an elective tracheostomy and attempts to administer oxygen by anyother means such as by Ambu bag and oropharyngeal airway should not be discontinued. The right-handed surgeon should grip the thyroid and the cricoid cartilages with the left hand and pull the laryngeal skeleton towards the head. The long midline incision should incise through skin and subcutaneous tissue on the first strokefromthe cricoid to the jugular notch (Fig. 46.8). The surgeon can then use the fingers on the left hand to push apart the skin and the forefinger to palpate for the trachea, while the assistant clears the blood by mopping or suction. The second stroke of the scalpel aims to reach the front of the trachea. More strokes can always be made and they take little time. Once the trachea is reached, it can be entered via a midline slit wherever convenient. The cricoid is best avoided if possible. The tracheostomy tube can be inserted with the help of a dilator or the back end of the scalpel, which can be

Tracheostomy used to stent open the tracheal slit. The cuff is then inflated and haemostasis secured.

Physiological changes after a tracheostomy 1 A 10-50% reduction in anatomical dead space. This contributes to better pulmonary ventilation. 2 Loss of voice. Theair bypass of atracheostomy makes it difficult for the patient to phonate. Provided that a phonating larynx is present, the patient can be trained to phonate either by finger occlusion of the tube or by the use of special phonating valved tubes. 3 Difficulty in swallowing. This is secondary to tethering of the trachea to theskin by the tracheostomy tube, which impedes the swallowing motion. An overinflated cuff can compress the oesophagus, causing dysphagia. 4 Loss of humidification. In the presence of a tracheostomy, cool dry air directly hits the tracheobronchial tree. This interferes with ciliary function, allowing accumulation of secretions. 5 Loss of glottic valve closurerequiredfor effective coughing.

Post-tracheostomy care 1 Humidified warm air shouldbe provided for 48-72 h to prevent crusting and tube obstruction. 2 Regular suction and physiotherapy should be carried out for the chest in the early postoperative days. 3 A writing-pad should be provided to aid communication and whenpossible train the patientto vocalise with the tracheostomy tube in situ. 4 As far as possible, encourage the patient to care for hidher own tracheostomy tube.

Complications Immediate

1 Haemorrhage,

33 I

2 Recurrent laryngeal nerve injury. 3 Apnoea secondary to the loss of hypoxic drive. 4 Cardiac arrest secondary to the adrenaline surge and the sudden rise in pH as CO, is washed out. 5 Air embolism. 6 Pneumothorax. Intermediate

1 Cellulitis. 2 Surgical emphysema. 3 Tube dislodgement. 4 Tracheal-wall ulceration or necrosis. 5 Dysphagia. 6 Pneumomediastinum. 7 Tube obstruction Late

at four 1 Stenosis of the trachea can occur sites-suprastomal, stomal, cuff and tip. 2 Tracheocutaneous fistula can follow if traa cheostomytubehas been inserted formorethan 3 months. Surgical closure is required.

References and further reading Eibling DE, Bacon G & Snyderman CH (1992) Surgical management Adv.Otolaryngol.HeadNeck Surg. 6, of chronicaspiration. 93-113. Jackson C (1909) Tracheostomy. Trans. Am. Laryngol. Rhinol. Otol. Soc. l, 337-45. Rosas Meneses M H & Betancourt Landeros VM (1970) History of tracheostomy. Semana Med. Mexico 64, 21. Shehata MA (1981) History of laryngeal intubation. Middle East J. Anaestb. 6, 49-55. Stell PM (1973) Tracheotomy and tracheostomy. In: Ransome J, Holden H & Bull TR (eds) Recent Advances in Otolaryngology. Edinburgh, Churchill Livingstone, pp. 275-94.

Surgery of Paediatric Laryngotracheal Stenosis DAVID ALBERT

Introduction

between the split to fill in, eventually with new cartilage. (b) Augmentation uses grafts to expand the lumen by adding to the existing cartilaginous framework. Autograft costalcartilage is most oftenused, although bone or even allografts have been tried. (c) Stenting is animportantadjuncttotheabove techniques to stabilise reconstructions and to prevent restenosis. The expansion of the lumen may be at the expense of the function of the larynx. Substantial anterior and posterior grafts may allow achild to be decannulated, but the further the cords are separated, the more the function suffers. There are many combinations and modifications of the techniques described above. The relatively small number of patients requiring surgery mitigates against comparative studies. The choice of technique presented is more proactive than many readers may be used to, and also favours single-stage surgery where possible, as this avoids the dangers and difficulties of tracheostomy.

Surgery of laryngotracheal stenosis (LTS) involves more than expansion of the stenotic airway. It is complicated by the need to maintainthefunction of thelarynx to phonate and to provide protection for the airway. Stenosis offers a surgical challenge at many sites in the body but in few is the interrelationship with functionso delicate. Expansion of the stenotic airway canbe achieved in a number of complementary ways. 1 Natural resolution of stenosis fromgrowth of the surrounding cartilaginous structure appears an attractive option. However, resolution of significant acquired stenosis is rare. 2 Dilatation aims to stretch stenosis but is seldom successful, asacquired stenosis contains elastic elements which contract unless dilatation is combinedwith steriting. 3 Laser vaporisation offers a promise of instantaneous elimination of stenosis. This promise is often unfulfilled, as stenosis re-forms. 4 Resection of thestenotic segment withend-to-end anastomosis is only possible if the stenosis is separate from the glottis. This is very rarely the case in acquired stenosis; hence theauthor’s preference fortheterm ‘laryngotracheal’ stenosis. Restenosis at the anastomotic site may also occur. 5 Most surgeons now rely on splitting and augmentation to treat significant stenosis, with costal cartilage grafting being the preferred option. (a) Splitting divides thecartilaginousframework. Splits can be anterior, posterior, lateral or castellated, asinlaryngotracheoplasty.Whencombinedwith stenting, splitting increases the lumen but leaves areas

General indications and choice of technique There are three main groups of children who require laryngeal reconstruction. Intubated patients who cannot be extubated because of laryngotracheal stenosis

Conservative measures should be tried first, such as antirefluxtreatment,steroids and at least 5 days between attempts at extubation. If these fail the alterna33”

Surgery of Saediatric ~ a r y n g o t ~ ~Stenosis c b e ~ ~ 33 3 ~.

tives to tracheostomy are as follows: 1 cricoid split; 2 single-stage laryngeal reconstruction (without tracheostomy). The single-stage procedure is a modified cricoid split in which a cartilage graft is inserted inthe split. This improves therate of successful extubationand,as it does not seem to be associated withany higher complication rate, would seem to be the procedure of choice. ”

\”-

Tracheostomised patients with laryngotracheal stenosis

Mild stenosis may improve sufficiently to allow decannulation without surgery but almost all patients with grade 111-IV stenosis (see under Preoperative evaluation) will require surgery before decannulationcan proceed. Laryngeal reconstruction is now being undertaken at an earlier age, as technically this provides few real difficulties. There are obvious advantages of early decannulation for both the parents and the child. Ideally all children should be decannulated well before starting school. The options are: 1 cartilage grafting with tracheostomy maintained; 2 cartilage graftingwithtracheostomy closed at the same time as a single-stage procedure; 3 cricoid split “anterior, posterior or lateral splits-or laryngotracheoplasty. Thetraditionalapproach is to use anteriorcartilage grafts for mild stenosis (grades 1-11), with addition of a posteriorgraft if the stenosis is severe or prominent posteriorly. Some surgeons would use a posterior graft for interarytenoid scarring, although a Z-plasty to the scar is more appropriate. A more recent development is to close and support the tracheostomy site at the same time as the reconstruction in a sin&-stage procedure, if significant suprastomal collapse is present. Congenital stenosis in which the cricoid is small but not scarredhas conventionally been treatedwitha laryngotracheoplasty. Anterior cartilage grafting is an alternative, particularly if the stenosis is severe. A larynx scarred and disorganised by previous surgery can be salvaged by a four-way cricoid split and the long-term use of a stent. A posterior split without grafting can be used in mild to moderate stenosis to allow the cricoid to spring open sufficiently to use a reasonable-size anterior graft without separating the posterior commissure.

Patient.s . without a tracheostomy but*who have recurrent croup, increasing stridor, reduced exercise tolerance or failure to thrive ~

~

.~

Prior to the introduction of single-stage procedures the decision to operate on these children was very difficult, as a tracheostomy was required. A single-stage procedure using a simple anteriorgraftandaperiod of postoperative intubation is now the method of choice and is very successful, as the stenosis is usually relatively mild. Surgery should be considered in children with stenosis requiring intubation for croup on more than two occasions. Some prematureneonatesareextubated only to develop progressive stridor as they grow and their stenosis does not. If the indication is reduced exercise tolerance, arespiratoryopinionshould be sought to exclude an element of asthma. Similarly, children with failure to thrive need to have other possible causes excluded.

Contraindications Single-stage procedures contraindicated are if pulmonaryfunction is inadequate or if the child is under 1.5kg. Surgery is also contraindicated unless appropriatepaediatric ITU facilities are available, as the child will need postoperative intubation. Any other medical problem may adversely affect thechance of success. In conventionalreconstruction,posteriorgraftsare contraindicated in children with arytenoid fixation, as the resulting larynx will be incompetent. If the larynx is still full of active granulations, indicating active perichondritis, surgery is best delayed.

Preoperative evaluation Endoscopic assessment

Endoscopic assessment is essential to decide if and when surgery is indicated and to choose the most appropriate technique.

Degree of stenosis

A number of different grading systems have been used but the only system to have been tested against prognosis is that of Cotton, which relies on the percentage of the lumen obstructed by stenosis.

334

Chapter 47

Grade I 0-50% Grade I1 51-70% Grade I11 71-99% (lumenpresent) Grade IV No lumen The length or thickness is much less important, unless the stenosis is sufficiently thin tobe almost aweb, which can then sometimes be lasered segmentally. Site of stenosis

Whether the site is anterior, posterior or lateral determines where to split thelarynx and insert cartilage grafts. Arytenoid mobility

Arytenoid fixation is easily missed unless specifically excluded and will adversely affect results. There is no reliable treatment. Interarytenoid scar

This needs to be excluded by separating the arytenoids with two probes. Gastro=oesophagealreflux

This hasrecently been shown tohave a marked effect on the healing of the larynx, both at the time of the initial injury and after laryngeal reconstruction. Barium swallow is a poor indicatorof reflux. Although pH studies or isotope milk scans are better, they do not usually measure upper oesophageal or pharyngeal pH. Double pH studies, which simultaneously measure upper and lower oesophageal pH, are the ‘gold standard’, but there are few normative data to determine how much acid reflux is needed to affect thelarynx. At present, therefore, there is a case to treat all patients undergoing laryngeal surgery with a 6-week course of H,-blockers, extending this to 3 months if reflux is demonstrated by whatever means. informed consent

In grade 11-111 stenosis, initial success should be in the order of 70-85%, with over 95% achieving decannulation after further surgery. In grade IV stenosis, in which no lumen is present, the results are much worse, with 60% initial success and only 75% being eventually decannulated. Most potential complications, while important, would not sway parents against surgery. The possibility

of poor vocal quality after surgery needs to be carefully discussed. Overall, one-third will have a normal voice, one-third anabnormalbutunderstandable voice and one-third a sufficiently poor voice to make communication difficult. These lastpatientsare usually those with a complete or near-complete stenosis who had no voice preoperatively. There are no large studies yet with pre- and postoperative voice results to determine how often surgery has an adverse or a beneficial effect on the voice.

Prophylactic a n t i ~ i o t i c ~ Thereare no studies to show efficacy of antibiotic prophylaxis in paediatric LTS surgery. If a graft is inserted and particularly if a stent is used, prophylaxis is recommended. A broad-spectrum antibiotic suitable for upper respiratory organisms such as amoxycillin is often used. In sick neonates undergoing cricoid split, the trachea is probably not sterile; antibiotics should therefore be chosen on the basis of tracheal aspirates and with the agreement of the neonatologist.

Relevant anatomy In paediatric and neonatal tracheostomy, tracheostomy stay sutures areessential, as even in neonates the trachea lies quite deep. It is also possible to pull almost all of the intrathoracic trachea up into theneck, so excessive neck extension should be avoided. The left brachiocephalic vein and the pleural apex are relatively higher in the paediatric neck. In neonates the distance from stoma to carina can be as little as 2.5 cm, making tubepositioning critical. The standard approach to the paediatric larynx is a midline laryngofissure. In the previously operated neck, staying strictly inthe midline will avoid interference with the major neck vessels. The dissection in tracheal resection has to remain right up against the trachea to avoid damage to the recurrent laryngeal nerves. Posterior and lateral cricoid cuts must only just broach the cricoid, in order to avoid damage to the oesophagus and the recurrent laryngeal nerves respectively.

Operative technique Thestandard laryngofissure is described first and in detail. The more extended procedures which follow do not repeat the description of this basic approach unless there are important variations.

Surgery of Paediatric Laryngotracheal Stenosis

335

Procedure

Fig. 47.1 Tape passed around chin to elevate upper skin flap.

(a) Basic laryngofissure Preparation

General anaesthesia This is initiated via the tracheostomy tube,which is then changed for anarmouredendotrachealtube (ET) secured caudally. Theanaesthetictechniqueforpatientswithouta tracheostomy is covered in single-stage procedures (Sections c and e).

1 Soft-tissue dissection should be in themidline through fascia and strap muscles. The author routinely divides the thyroid isthmus with diathermy and thenretracts the two halves with a stay suture. Two Aberdeen retractors (Fig. 47.2) provide good access, while most other selfretaining retractors get in the way. 2 The anterior laryngofissure is started inferiorly and then carried superiorly. A Beales dissector placed in the midline between the vocal cords ensures that, if needed, division of the anterior commissure is central. Often the laryngofissure only needs to be taken halfway up the thyroidcartilageand inferiorly through the first ring (Fig. 47.3). 3 Posterior division of the cricoid, if required, should not proceed until bleeding from the anteriorincision has been controlledwithadrenaline-soaked neurosurgical patties. Harvesting and placement of cartilage grafts are dealt with in Section c. 4 Closure is important, as the scar will be visible. A subcuticular nylon suture is easily removed in any child and gives an excellent cosmetic result. A drain is required if there is an air leak or if haemostasis is incom-

Surgical drapes and equipment Forthose used to operating in adultsthestandard drapes are rather cumbersome. The author prefers following the usual skin preparation with plaster remover to provide good adhesion for a perforatedplastic drape. A piece of adhesive’tape fixed tightly to the head of the table and under the chin provides skin traction on the upper flap and gives a clear field (Fig. 47.1). It is especially important in revision surgery to keep thehead central in order to maintain a midline laryngofissure. Surgical instrumentsshould be appropriateforthe child’s age. Microbipolar forceps aremore helpful than. skin infiltration in preserving adryoperative field.

Fig. 47.2 Aberdeen skin retractors.

Incision

A horizontal skin-crease incision should be at the level of the cricoid. The length depends on the need for access to thetracheostome and to the upperborder of the thyroid cartilage.

Fig. 47.3 Laryngo fissure, showing vertical extent.

3 36

Chapter 4’7

plete. Saline poured into the wound as the anaesthetist increases the airway pressure will detect an air leak. A dressing is not required unless an open drainage system is used. Postoperative intubation and sedation are covered in Section b. Complications

Damage to the anterior commissure can occur if the laryngofissure is not in the midline. Surgical emphysema will occur if an air leak is present andnodrain is inserted. Occasionally the wound will become infected; this is more likely to occur if a stent is secured with a buried suture. (b) Splits of the cricoid cartilage: anterior/

Procedure

1 Oncetheanterior split is complete, the ET can be withdrawn temporarily to allow the posteriorsplit to be performed. It is usually necessary to feed the tube back past the split for ventilation on a number of occasions until the split is complete. 2 Bleeding needs to be carefully controlled before and duringposteriorandlateral splits in order to prevent damage to the oesophagus or recurrent laryngeal nerves. A useful sign that posterior division of the cricoid is complete is that the two halves of the larynx should become much easier to separate (Figs 47.447.6). 3 A larger-size nasotracheal tube can now be inserted. This is simply achieved by reintubation in the normal

posterior/lateral/four=way

Specific indications 1 Anterior t- posterior split in long-term ventilated neonates andother children withoutatracheostomy who fail extubation. 2 Anterior split in patients with a tracheostomy and a soft, mild stenosis (Cotton grades 1-11). 3 Four-way split in severely disrupted larynges and revision surgery (tracheostomised children). Specific contraindications

1 Weight under 1.5kg. 2 Poor pulmonary function. 3 Significant otherairwaypathology

such asinter-

Fig. 47.4 Posterior split of the cricoid cartilage.

arytenoid scarring or tracheomalacia. Particular points of operative technique

The technique of laryngofissure as described above is used with the following modifications. Preparation

Antireflux cover should commence preoperatively, withsteroidsstarted on the fifth postoperativeday (dexamethasone0.25 mg/kg initially, then 0.1 mg/kg 4.d.s. until 24 h postextubation). Initial intubation will be with a smaller-than-expected ET. As the child will need to be reintubated with a larger tube after thesplit is complete, access to the face must be available to the anaesthetist. Fig. 47.5 Scissors used to check division of posterior cricoid lamina.

Surgery of Paediatric Laryngotracheal Stenosis

3 37

Complications

Traumaticreintubationcancreatea false passage throughthe split andinto the neck, complicating attempts at resuscitation. Failed extubationcan be managed with a further period of intubation, a repeat cricoid split, a single-stage laryngeal reconstruction or a tracheostomy. (c) Single-stage reconstruction to avoid tracheostomy

Specific indications Fig. 47.6

way, with the surgeonhelping the tube past the split and into the trachea. 4 A tubeone size larger than predicted can be used if this is possible without trauma to the mucosa. The nasotracheal tube is secured with a Tunstall connector to a headband. 5 A drain is required to manage the air leak, as the anterior split is neither closed nor covered Postoperative management

Postoperative sedation should be reduced as much as possible so that the child is awake and responding, but without risking accidental extubation.Most children with normal lung function can cope with continuous positive airway pressure (CPAP)rather than assisted ventilation. Postoperative paralysis and ventilation are used by some surgeons to prevent extubation, but their strategy has significant side-effects of muscle weakness and lung collapse. Testing for an air leak aroundthetubecan help determine whento extubate. Thisis achieved by increasing the ventilatory pressure and listening at the mouth or with a stethoscope over the larynx. This has been shownto be goodpredictor of eventual successful extubationin paralysed ventilated patients,butin lightly sedated patients an air leak may be absent because the cords are clamped around the tube. In nonparalysed non-ventilated patients, a workable protocol is to extubate on the third postoperative day if a leak is present or otherwise on the fifth day. If the child requires reintubation after accidental or planned extubation, there should be time to return the child to theatre and reintubate carefully, with the bevel turned posteriorly to avoid the anterior split.

l Failed extubation, particularly in long-term ventilated neonates. 2 Recurrent croup due to mild subglottic stenosis. 3 Progressive stridor. 4 Reduced exercise tolerance. 5 Failure to thrive. Specific contraindications

As for cricoid split (Section b). Particular points of operative technique

Apart from the graftplacement, moit points arecovered under basic laryngofissure andthe section on cricoid split. Anaesthesia

If the child is not already intubated, it is important not to force a larger ET than will fit comfortably, asthis will disrupt the subglottic mucosa. As anaesthesia may be suboptimal with a small tube, the laryngofissure should be performed quickly and efficiently to allow placement of a larger tube. A posterior graft is very seldom necessary in this group of patients, but, if it is, a separate, low, temporary tracheostomy can be used to continue anaesthesia while the posterior graft is placed. Respirationshould be spontaneous,as this allows more time for tube changes and for graft placement. Procedure

1 The anterior split should be from the first tracheal ring to halfway upthethyroid, being extended if needed. 2 Graft harvest is from the right costal margin. In girls a submammaryincision can be used, although, while the scar may be preferable, there are some concerns that the

338

Chapter 47’ Postoperative care and complications

These are the same as in the basic laryngofissure and the cricoid split (Sections a and b). Laryngotracheoplasty Specific indications

Congenital stenosis in tracheostomised children. Particular points of operative technique Fig. 47.7 Notch for the cricoid.

Anaesthesia As these children have a tracheostomy, this is as in the

basic laryngofissure (Section a). Procedure

The approach and preparation are similar to those for an anterior cricoid split, but the incision is castellated from the thyroid, through half the cricoid and through Fig. 47.8 Bevelledgraft.

breast function couldbe impaired. Cartilage of sufficient size and shapeshould be harvested, takingcare to preserve perichondrium on one side. Test for a pneumothorax, using saline irrigation. A drain is not usually needed. Marcaineinfiltration or a lignocaine infusion will help control postoperative pain. 3 Graft sculpturing should result in a graft which provides significant expansion of the lumen, while being extremely stable. This is essential in a single-stage procedure,asthestenting benefit of thetube is lost at extubation. A relatively thick graft, grooved laterally for the thyroid, cricoid and first ring, should be sufficiently secure for it not to be displaced even prior to sutures (Figs 47.7-47.10). If the cartilage is very thin or soft, a T-shaped piece of cartilage is less likely to prolapse into the lumen (Fig. 47.1 1). 4 Graftsuturesshould be 510 or 6/0 absorbable synthetics, placed through each side of the cricoid andwith ‘U’ suturesthroughthethyroid and first tracheal ring. A minimum of foursuturesarethus required.Thesuturesshouldnotprotrude into the lumen. 5 A drain should be used unless the resulting graft fit is airtight, particularly if the child could need a period of ventilation.

Fig. 47.9 Grooved graft.

I

Fig. 47.10 Sutures.

Surgery of Paediatric Laryngotracheal Stenosis

3 39

(d) a4.aryngotracheal reconstruction with anterior It posterior graft in tracheostomised children

Specific indications

1 Subglottic stenosis which is unsuitable for a singlestage procedure, i.e. severe (Cotton grades 111-IV) stenosis. 2 Other medical problems. Fig. 47.11 Anterior graft: T-shaped cartilage.

Particular points of operative technique

Anaesthesia Anaesthesia and approach are laryngofissure (Section a).

for as a

basic

Procedure

I

Fig. 47.12 Laryngotracheoplasty: castellated incision.

Once the larynx has been opened, the need for a posterior graft can be assessed. A pair of callipers will help ensure that suitable-length grafts are obtained, as described above in single-stage procedures. Some surgeons prefer to groove the posterior graft (Fig. 47.13) to fit between the cricoid laminae, although a thick graft is needed. A square-edged graft is thinner andcan be equally secure (Fig. 47.14).Perichondriumshould be preserved internally. Placement of the four to six: 6/0 absorbable sutures is aided by preloading of all sutures through graft and cricoid prior to final ligation (Fig. 47.15). A stent is advisable if a posterior graft has been necessary. A Silastic-roll or an Aboulker stent can be used. The stent is secured with a 0-Prolene suture, which is taken out laterally through the strapmuscles and is tied once the anterior graft has been placed.

alternate tracheal.rings (Fig. 47.12). The fingers of the incision are ineffect multiple advancement flaps and, by separatingthe two sides of the incision, thetracheal diameter is increased without the need for a separate graft.The space between thecartilage fills in with fibrous tissue and native cartilage. Absorbable 5/0 sutures are required. A drainwill be required, as theresult is never airtight. Postoperative care and complications

These are the same as in the basic laryngofissure (Section a).

Fig. 47.13 Grooved posterior graft.

340

Chapter 47 Particular points of operative technique Anaesthesia

If the tracheostome is to be closed at the same time as the reconstruction, this tube must be accessible so that it can be removed when the patient is nasotracheally intubated. Procedure

Fig. 47.14 Square posterior graft with preserved internal perichondrium.

The stoma is excised by extending the anterior laryngofissure. Thepatient is thenreintubated and the stenotic segment and the stoma grafted (Fig. 47.16). Cotton uses a lower ‘T’ graft, which supportsthe stomal area, but a single long graft will often suffice. A drain should be used unless the resulting graft fit is airtight, particularly if the child could need a period of ventilation. Postoperative care and complications

These are thesame as in thebasic laryngofissure and the cricoid split (Sections a and b). (f) Surgical decannulation

Specific indication Fig. 47.15 Four to six preloaded sutures.

Patients whose stenosis has resolved or been treated but who have significant suprastomal collapse.

Complications

The stent is probably helpful only in the first 2 weeks and can act as a conduit for reflux on to the repaired larynx. Granulations occur at the top of the Silasticroll stent but settle once it is removed. To remove the stent, the sutureis cut in the neck and thestent removed endoscopically. Further examinations are required once thestenthas been removed to ensure that the airway is adequate and stable prior to decannulation. If suprastomal collapse is present, a surgical decannulation (see below) may be necessary. (e) Single-stage reconstruction and closure Specific indication

Tracheostomised patients with grade 11-111 stenosis and no medical or other contraindications.

~

Fig. 47.16 Anterior graft with tracheostome closure.

Surgery of Paediatric ~ ~ r y n g o t ~ ~Stenosis c b e a ~ 3 4I Particular points of operative technique Anaesthesia

The child is intubated nasotracheally.

sternomastoids,which help preventtracheal collapse. A drain prevents surgical emphysema. Occasionally a cartilage graft confined to the stomal area is used.

Procedure

Conclusion

The tracheostomy tract is excised, taking care not to tent the stoma and preserving tracheal cartilage. The stoma is closed in layers, minimising any air leak and on to the using a couple of stronglateralsutures

The successful paediatric laryngeal surgeon is one who is able to assess the patient pre-and postoperatively andthen flexibly apply surgical techniques to the individual.

Surgery of Hypopharyngeal Diverticula ALEXANDER C . VLANTIS

Surgery forsymptomatichypopharyngeal diverticula cures 80% of patients and improves symptoms in the remaining 20%. In skilful hands, the procedure results in no mortality and alowrate of complications (Barthlen et al., 1990).

Bndications Ahypopharyngeal(Zenker’s) diverticulum that becomes symptomatic. Symptoms include long-standing dysphagia, which may be progressive. The patient has a sensationof food sticking in the throat and requires several attempts to swallow it, lengthening the time taken to eat a meal. Foul-smelling undigested food may be regurgitated, and aspiration of contents leads to episodes of coughing, with orwithout aspirationpneumonia and lung abscesses. Hoarseness and weight loss may occur. There are usually no signs, but a gurgling sound on palpation of the neck is occasionally present. Indirect laryngoscopy may show pooling of secretions in the hypopharynx. Plain soft-tissue films of the neck may showa retropharyngeal fullness or an air-fluid level. Contrast swallow shows a smooth rounded sac or diverticulum arising posteriorly in the midline at the level of C6, which usually extends to the left posterolateral region of the neck.

Preoperative management Any consequences of the diverticulum, such as malnutrition, dehydration and lung infections, should be treated. Fine-bore enteral feeding tubes are particularlyuseful in the malnourished patient.

The size of the diverticulum should be assessed on the contrast swallow, gradedaccording to Brombart and appropriate treatment planned (Barthlen et al., 1990). Clear fluids are given for 24 h prior to surgery.

Relevant anatomy The inferior pharyngeal constrictor consists of two parts,thethyropharyngeus and thecricopharyngeus muscles (Fig. 48.1).Thethyropharyngeus arises from the oblique line on the thyroid cartilage and a fibrous arch between the thyroid and cricoid cartilage, and inserts into the pharyngeal raphein the posterior midline. Theupper fibres pass obliquely posterosuperior and overlap the middle constrictor. The lower fibres lie horizontally, parallel to the cricopharyngeus. Thecricopharyngeus muscle is thicker thanthe thyropharyngeus, passes uninterrupted from one side of the cricoid to the other around theback of the pharynx, and has no muscular raphe. The circular muscle fibres of the oesophagus lie below and parallel to the cricopharyngeus, and may blend with it. Below the level of the glottis, the thyropharyngeus is unsupported by the middle constrictor, resulting in a posteriorarea of weakness at thejunction of the thyropharyngeus and cricopharyngeus muscles, known as Killian’s dehiscence. Reduced cricopharyngeal compliance (Cook et al., 1992) leads to the posterior herniation of mucosa and submucosathrough Killian’s dehiscence to forma diverticulum-Zenker’s diverticulum-which lies posteriorly between the pharyngo-oesophagus and the prevertebral fascia. Therecurrent laryngeal nerve lies in thetracheooesophageal groove, and usually crosses behind the infe-

Surgery of ~ y ~ o ~ b a r y n gDiverticula eal Table 48.1 Stage and management.

343

to the sac and is at risk of damage during exposure of the diverticulum.

Anaesthesia

Before induction of general anaesthesia, voluntary selfinduced regurgitation of food by the patient should be encouraged, as it may empty the pouch (Thiagarajah et al., 1990). Thesmoothinduction of anaesthesia and a cuffed endotracheal tube (ET) prevent aspiration and tracheobronchial Contamination, permitting safe controlled ventilation and oxygenation. Local anaesthesia is an acceptable alternative in patients unfit for general anaesthesia (Schmit & Zuckerbraun, 1992). rior thyroid artery as it runs superiorly, accompanied by the laryngeal branch of the inferior thyroid artery. The nerve continues in the groove, passing medial to the inferior margin of the cricopharyngeus, behind the articulation of the inferior cornu of the thyroid cartilage withthe cricoid cartilage, and so entersthelarynx behind the cricothyroid joint. The nerve passes anterior

Fig. 48.1 Lateral view of the pharyngooesophagus.

Antibiotics

Broad-spectrum antibiotic cover is given at induction. Pharyngoscopy

The sac is identified posterior to theopening

of the

344

Chapter 48

oesophagus, washed, the contents aspirated to remove all food and barium, and inspected carefully to exclude malignancy. It is then packed withribbon gauze to allow easy identification, with one endremaining out of the mouth to allow the anaesthetist to remove it with ease when required. A fine-bore nasogastric tube is inserted under direct vision into the oesophagus.

the wound. The correct subplatysmal plane is reached when there is a sudden ‘give’ in the wound. The cut edges of platysma part with ease, causing a widening of the field. The great auricular nerve should be preserved. Procedure (Fig. 48.2)

Position of the patient

Skin flaps

The patient is placed supine, with the occiput resting on a head ring and pack a under the shoulders to hyperextend the neck. The chin is turned away from the side of the incision.

Superior and inferior myocutaneous skin flaps are elevated in the subplatysmal plane above the superficial veins of the neck, to widely expose the anterior border of the sternocleidomastoid muscle. Large self-retaining retractors or sutures are used to keep the operating field exposed.

cisio

The preferred technique isvia alongitudinal cervical incision positioned along the anterior border of the left sternocleidomastoid muscle, from the level of the hyoid bone to just above the clavicle. Do not use the left side if the patient has a right-cord palsy. Alternatively a left transverse cervical incision in a skin crease may be used, placed at the level of the cricoid cartilage. The neck incison is carriedthroughthe platysma muscle while applying countertraction on each side of

Division of omohyoid muscle

The superficial layer of the deep cervical fascia is incised alongtheanteriorborder of thesternocleidomastoid muscle, and the plane between the muscle laterally and the larynx and strapmuscles medially is opened. Dissection is carried from the level of the thyroid notch to the clavicle. The sternocleidomastoidmuscle isretracted laterally to expose the carotid sheath and anterior belly of the omohyoid muscle, which passes in an oblique direc-

Fig. 48.2 Cross-section through lower neck before and after dissection.

Surgery of ~ y p o p b a r y n g e a lDiverticula tion across theoperative field fromsuperomedial to inferolateral. A combination of sharp and blunt dissection is used to expose the omohyoid and strap muscles. The omohyoid muscle is divided, taking care to observe the internal jugular vein (IJV), which lies deep to it. Exposure of the infrahyoid muscles

The field of exposure is deepened by keeping the larynx and strap muscles as the medial border of the dissection and thecarotidsheathasthelateralboundary.The sheath is gently retracted laterally to avoid undue pressure on thecarotid.Theposteriorborder of the sternohyoid and sternothyroid muscles are dissected to reveal the thyroid lobe, and are retracted anteriorly, but they may be divided if necessary. The middle thyroid vein, which empties into the IJV, straddles the field and is divided. The recurrent nerve is hidden by the lobe of the thyroid gland, and lies anterior to the oesophagus in the tracheo-oesophageal groove. It runs to the lateral junction of the trachea, oesophagus and cricoid cartilage. Care is taken to identify and preserve therecurrent laryngeal nerve, which often appears as a flat, white, tortuousstructure, so thatitcan be avoided in the dissection of the sac. However, the technique described shouldallowtheprocedure to be carried out safely

Fig. 48.3 Cricopharyngeal myotomy. Note incision o f thyropharyngeus, cricopharyngeus and circular muscle fibres of the oesophagus.

345

when the recurrentlaryngeal nerve is not identified. The ipsilateral lobe of the thyroid glandis turned forward to expose the posterolateralsurface of the pharynx and the oesophagus within the operative field. Entry into the retropharyngeal space

When the anterolateral border of the vertebral bodies has been reached, finger dissection opens a plane between the pharyngo-oesophagus and the pre-vertebral fascia, so that theretropharyngeal space is entered anterior to the vertebral bodies at a level superior to the inferior cornu of the thyroid cartilage. This avoids injury to the recurrent laryngeal nerve, since the lateral dissection is all above the inferior cornu of the thyroid cartilage, thepointat which therecurrent laryngeal nerve enters the larynx. Once the retropharyngeal space is entered, dissection is carried from above downwards towards the posterior aspect of the cricoid cartilage (Levine et d., 1979). The pharynx is freed from the pre-vertebral fascia so that the larynx can be rotated away from the field to reveal the posterior aspect of the pharynx. In this way it becomes possible to rotate the larynx away from the surgeon and to identify the sac without injury to the recurrent laryngeal nerve. If rotation of the larynx is achieved using a hook, it should not be applied below

346

Chapter 48

the midpoint of the thyroid cartilage since the recurrent laryngeal nerve passes behind the inferior cornu of the thyroid cartilage and may be damaged(McKenna &: Dedo, 1992). The sac is therefore approached from the posterior midline and notlaterally. If the inferior extent of dissection requires extension, it may be necessary to ligate the inferior thyroid vessels, which approachthethyroid gland from the thyrocervical trunk behind the carotid sheath. The inferior thyroid artery is divided well away from the thyroid gland and clear of the recurrent laryngeal nerve, which should be identified. Location and dissection of the sac

The sac is usually palpated and identified without difficulty. It is dissected from the surrounding structures by sweeping tissue away from the fundus, which may be gently grasped with a Babcock forceps and pulled out of the wound. Continuesweeping tissue towards the pharynx until the neck of the sac is exposed. When only mucosa remains, the diverticulum is completely mobilised. The neck is dissected to thepoint where the mucosal sac protrudes through the muscular defect of the pharynx. Directly inferior to the neck of the sac lies the cricopharyngeus muscle. Care must be taken not to pull normal mucosa outthrough the deficiency and make it part of the sac. Cricopharyngeal myotomy (Fig, 48.3)

Thecricopharyngeal myotomy is performedprior to excision of the sac and is mandatory in all patients with Zenker’s diverticulum. Once the pharyngeal pack has been withdrawn and the pouch collapsed, a 32-French-gauge Maloney bougie or cuffed ET is passed and guided by the surgeon into the proximal oesophagus. An extramucosalplane is developed just inferior to the neck of the sac, using a fine-pointed curved forceps. The bougie or inflated endotracheal cuff causes the cricopharyngeal muscle to be stretched in order to accurately divide fibres without damage to the underlying mucosa. The transverse fibres of the cricopharyngeus are divided foradistance of Scm, and thecut edge of the muscle is dissected away from the mucosa for 1-2 cm. The myotomy should be extended up to the thyropharyngeus to ensure that all fibres of the cricopharyngeusare divided, and distally for 4cm into the circular musculature of the oesophagus (Fig,

48.3). If the plane is difficult to establish, the muscle fibres must be sectioned carefully witha blade. The mucosa of the pharynx and oesophagus should protrude freely when the myotomy is adequate. Resection of the sac

The operative field isnow loosely packed with dissecting swabs to prevent contamination. Insert a sutureat either side of the neck of the pouch, but keep the suture long and clamp the end of it with a forceps (Fig. 48.4). This allows better control of the mucosa during resection and closure. Use a sharp blade to divide the neck, leaving a stump of mucosa for closure. The bougie prevents the removal of too much oesophageal mucosa and so avoids cicatrisation of the oesophagus. The oesophageal lumen can be inspected to exclude intra-oesophageal pathology such as webs. A cut-and-sew technique may be employed. Repair of the pharyngeal wall

The pharynx is closed with absorbable suture material, using a continuous Connell suture placed in the horizontal plane from each corner,ina similar way to the pharyngeal closure following a laryngectomy. The mucosal suture line is reinforced with a second layer of interrupted sutures. Alternatively, a linear stapler may be used. The anaesthetist fills the oesophagus and pharynx with air while the wound is immersed in saline to ensure there is no leak.

Fig. 48.4 Resection and closure.

Surgery of ~ y p o p b a r y n ~ eDiverticula al Closure

Once complete haemostasis is obtained, the wound is washed with warm saline. A suction drain is placed into the retropharyngeal space and brought out through a separate stab incision or the lower border of the wound. The platysma and subcutaneous tissue are closed with interrupted sutures, and the skin is closed with sutures or clips.

IV fluids are given for 24 h until tube feeding is established. A water-soluble contrast swallow is performed on the fifth postoperative day to exclude a leak. If a leak is present, thepatient is kept off oral feeding fora refurtherperiod, usually 7 days, andtheswallow peated. If no leak is present and drainage is minimal, the drain is removed and a soft diet commenced.

1 Mediastinitis may be alethalcomplication, and is usually secondary to a leak, which may be excluded ith the aid of a contrast swallow. A pharyngocutaneous fistula should, after aperiod of feeding through a nasogastric tube,close spontaneously. 3 Unilateral vocal-cord paresis is due to injury to the recurrent laryngeal nerve. This can be avoided by approaching the sac from the posterior midline rather than the lateral approach. Recurrence of dysphagia will occur if the cricopharyngeal myotomy is inadequate or incomplete. 5 Pharyngeal stenosis may result from excessive mucosal resection.

1 Dilatation of the cricopharyngeal sphincter consistently fails and recurrence rate is 100%. 2 Dohlman’s operation or endoscopic diathermic treatment of apharyngealpouch involves division of the upper part of thecommon wall of mucosa and cricopharyngeus muscle that separates the diverticulum from the oesophagus,and which acts as the sphincterto the pouch. The divided tissue includes mucosa and circular fibres of the cricopharyngeus. Thisis thus nomore thanan endoscopic division of thecricopharyngeus muscle. Instruments devised by Dohlman are essential. The special endoscope is passed so that its anterior lip

347

enters the oesophagus and the posterior lip enters the pouch, Thetransverse ridge so formed is then divided by diathermy or staple gun (Wouters & van Overbeek, 1990). The carbon dioxide or alternativelaser and the operating microscope may also be used. However,most patients require two or more operations, while the risk of mediastinitis and of missing a carcinoma are some of the disadvantages.

1 Cricopharyngeal myotomy alone can be used (Schmit & Zuckerbraun, 1992). 2 Diverticulopexy (Duranceau et al., 1983; Konowitz & Biller, 1989) ordiverticulum suspension avoids opening into the pharynx and its associated complications. After the diverticulum is completely free, the apex is sutured superiorly, without tension, to the pre-vertebral fascia. This allows the sac to drain continually, shrink and become asymptomatic. It is an alternative technique for the high-risk elderly patient. 3 Inversion (Bowdler & Stell, 1987; Morton & Bartley, 1993) or invagination of a small diverticulum into the oesophageal lumen avoids opening the pharynx and its associated complications.Resumption of oralintake, operation time and hospital stay arereported to be shorter.

Barthlen W, Feussner H, Hannig C, Holscher AH & Siewert JR (1990) Surgical therapy of Zenker’s diverticulum: low risk and high efficiency. Dysphagia 5 , 13-19. Bowdler DA & Stell PM (1987) Surgical management of posterior pharyngeal pulsion diverticula: inversion versus one-stage excision. BY. J . Surg. 74, 988-90. Cook IJ, Blumbergs P, Cash K,Jamieson GG & Shearman DJ (1992) Structural abnormalities of the cricopharyngeus muscle in patients with pharyngeal (Zenker’s)diverticulum. J . Gastroenterol. Hepatol. (Aust.) 7, 556-62. Duranceau A, RheaultMJ & Jamieson GG (1983) Physiologic response to cricopharyngeal myotomy and diverticulum suspension. Surgery 94, 655-62. Gregoire J & Duranceau A (1991) Surgical management of Zenker’s diverticulum. Hepato-Gastroenterology 39, 132-8. (1989) Diverticulopexy and Konowitz PM & Biller HF cricopharyngeal myotomy: treatment for the high-risk patient with a pharyngoesophageal (Zenker’s) diverticulum. Otolaryngol. Head Neck Surg. 100, 146-53. Levine H, Wood B & Tucker H (1979) Hypopharyngeal diverticulum and thecricopharyngeus muscle: aposterior surgical approach. Laryngoscope 89, 1600-7. McKenna JA & Dedo HH (1992) Cricopharyngeal myotomy: indications and technique. Ann. Otol. Rhinol. Laryngol. 101, 216-21. Morton RP & Bartley JR (1993) Inversion of Zenker’s diverticulum:

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’

the preferred option. HeadNeck 15, 253-6. Schnlit PJ & Zuckerbraun L (1992) Treatment of Zenker’s diverticula by cricopharyngeus myotomy under local anesthesia. Am. Surg. 5 8 , 710-16. Belg. Thiagarajah S, Lear E & Keh M (1990) Anesthetic implications of

Zenker’s diverticulum. Anesth. Analg. 70, 109-1 1. Wouters B & van Overbeek JJ (1990) Pathogenesis and endoscopic treatment of thehypopharyngeal(Zenker’s) diverticulum. Acta Gastroenterol. 53, 323-9.

r

r

r Maligna ongue, F and Alve NICHOLASD.STAFFORD

indications Unless the tumour is so advanced as to beobviously incurable, a tumour of any T stage can be treated surgically. For small (T1 and T2) primaries, the S-year survival rate is similar for radiotherapy andsurgery; a cure rate in the region of 70--7’S% should be expected. Primary surgery is preferableforlarger lesions (T3 and T4), particularly when there is involvement of the mandible, although planned postoperative radiotherapy will often provide the patient with the best chance of cure (Vikram et al., 1980). Such radiotherapy should commence approximately 6 weeks after surgery. Surgery is contraindicated where: 1 there is no realistic chance of long-term survival; 2 the disabilities produced by surgery (e.g. poor speech, impaired swallowingand facial disfigurement) are unacceptable to the patient. Many surgeons view total glossectomy as unacceptable; theauthor does not. If the patient has received radiotherapy and the tumour remains within the confines of the tongue musculature, then glossectomy is the only therapy left. Ultimately, the decision rests on what offers the best quality oflife for the individual patient.

orthopantomogram (OPG) remains very helpful in assessing mandibular invasion. Full upper aerodigestive tract endoscopy is mandatory in every case. Pain or trismus often prevents adequate assessment and biopsy of the tumourin the clinic situation. Endoscopy will also allow a second, synchronous primary to be excluded. Any suspect cervical nodesshouldundergo fineneedle aspiration for cytological assessment. Many of these patients havebeenheavy smokers and drinkers. Their generalmedical status is often poor. It is essential to assess theirnutritionalstatuspreoperatively and,if indicated, obtain respiratory function tests and an anaesthetic opinion before proceeding with surgery. A feeding gastrostomy should be considered at this stage for patients who have large primaries and who are going to require prolonged rehabilitation of their swallowing.

Preoperative management The presence of trismus should alert the surgeon to the possibility of tumour invasion of the pterygoid muscles. All patientsshould have a chest X-ray to excludea pulmonary primary or pulmonary metastasis. Imaging of T3 and T4 tumours should include CT and/or MRI scanning,fromtheskull base to thethoracic inlet, and preferablyperformed in thecoronal plane. An 349

Anatomy The boundaries of the floor of the mouth comprise the medial aspects of the horizontal rami and anterior arch of themandible. Its mobility is provided by the mylohyoid muscle, which takes origin from the mylohyoid line on thelingual surfaceof each horizontal ramus. The muscle inserts into a midline raphe and the centralportion of the hyoid bone. Along withthe digastric and stylohyoid muscles, mylohyoid maintains the hyoid bone in its suspended position. The digastric muscle subdivides the upper neck into the submental and submandibulartriangles. The former contains a few lymph nodes, which should always be dissected out when undertaking a neck dissection for a tumour of the anterior floor of the mouth or tongue.

3 50

Chapter 49

The submandibular triangle contains the submandibular salivary gland, whose deep portion wraps around the posterior free edge of mylohyoid, to lie between this muscle and hyoglossus. The submandibular (Wharton’s) ductrunsforward to its ostium in the anterior floor of the mouth. Thehypoglossal nerve runs in the floor of the triangle, passing between the mylohyoid and genioglossus muscles as it runs forward to supply the intrinsic and extrinsic muscles of the tongue (Fig. 49.1).

Fig. 49.1 Diagram of a coronal section through the mandible and floor of the mouth to show the relationships o f the Submandibular gland.

The lingual nerve provides the afferent supply to the mucosa of theanterior floor of themouthand tongue. It leaves the infratemporal fossa, crossing the stylopharyngeus to lie in the same plane as the hypoglossal nerve. The nerve is tethered to the superior part of the submandibular gland by the submandibular ganglion. Figure 49.2 illustrates the lymphatic drainage of the tongue and floor of the mouth. There is evidence that marginal vessels drain unilaterally while central vessels drain bilaterally. Contralateralnodal involvement is unusual unless the tumour is midline or large (T3 or T4), orthere has been a previous ipsilateral neck dissection. Figure 49.2 demonstrates that a supraomohyoid neck dissection (SOHND) will remove all of the ‘primary’ nodes draining the area. The procedure therefore allows the opportunity to sample and perform frozensection analysis on these nodes. However, a SOHND should not be undertaken if there is known neck disease; in such a situation a functional or radical neck dissection should be performed, as appropriate. From a surgical point of view, there are three other structures which merit special consideration when undertaking surgery in this region. The inferior alveolar nerve, a branch of the third division of the trigeminal nerve, runs into the mandibular foramen with the inferior alveolar artery (a branch of the maxillary artery) after the latter has given off its mylohyoid branch. It provides the nerve supply to the teeth of the lower jaw

Fig. 49.2 (a) Lymphatic drainage o f the tongue. (b) Lymphatic drainage o f the tongue, showing bilateral dis~ri~ution of the central vessels.

Surgery for ~ a ~ i g n Lesions an~ and theadjacent gingiva andthen emerges fromthe mentalforamenasthemental nerve. When raising a visor type of neck flap or approaching the oralcavity via an anterior mandibulotomy approach, care should be taken to preserve the nerves whenever possible; since anaesthesia of the lower lip is associated with a significant morbidity, especially in a patient whose oral function is already compromised. The lingual artery is the third branch of the external carotid artery (ECA) andbegins its course at the level of the greater horn of the hyoid bone. Characteristically, it loops over the tip of the greater horn before running anteriorly into themuscle bulk of the tongue. The vessel is prone to trauma at this site; while this is rarely of consequence if the tumour is ipsilateral, damage to the contralateral artery occasionally results in infarction of the hemitongue. Justasdamagetothe lingual arterycan render a normal ‘hemitongue’ functionally useless, trauma to the hypoglossal nerve after a contralateralhemiglossectomy or floor-of-mouth resection can result, from a functional point of view, in atotal glossectomy. The nerve is in danger while dissecting the submandibular triangle duringa neck dissection and also duringapartial glossectomy where the tumour has crossed the midline. Traction on tongue tissues can cause sufficient distortion to draw the contralateral nerve into the surgical field. If such a situation is anticipated, the safest manoeuvre is to demonstrate the path of the contralateral nerve by dissecting it out in the triangle.

A general anaesthetic (GA) is almost mandatory; it allows control of theairway and facilitates adequate haemostasis. Local anaesthesia, using infiltration of the soft tissues with l-2% lignocaine with 1 in 200000 adrenaline,shouldonly be used forthe smallest of anterior tumours in patients deemed unfit for general anaesthesia. Prophylactic antibiotic cover is advisable in any case where the intraoral resection is continuous with dissection in the neck. In such a situation, antibiotics reduce the risk of fistula formation. A 5-day regimen of cefuroxime (500mg q.d.s.) and metronidazole (400mg t.d.s.) or Augmentin (500mg t.d.s.) is very effective. Steroids are inappropriate unless the patient has a medical problem indicating their use. Patients on warfarin should be anticoagulated perioperatively using heparin,theINR being keptwithinthetherapeutic range. The patient is positioned supine with the head sup-

3 5I

ported on a ring. A sandbag under the shouldersis only necessary if a neck dissection is also being undertaken. Overhead lighting can be supplemented by the use of a good headlight. It is the author’s practice to perform tracheostomy a for all cases except a simple hemiglossectomy without neck dissection. Particularly in situations where the excision site is closed primarily or reconstructed using a local or regional flap, the risk of haematoma formation and airway obstructionis considerable. If a tracheostomyis not performed, the intra-oral work is more easily undertaken if the patient has been intubated nasally. It is theauthor’s policy to undertake anSOHND when surgically treating a T2, NO tumour. Any suspicious nodes are sent for frozen-section analysis and the dissection is converted to a full functional or radical neck dissection as appropriate. Node-negative T3 and T4 tumours should undergo an ipsilateral full functional neck dissection. If theprimarytumour crosses the midline, the clinically negative contralateral neck should ND. Whentheprimarytumour is anteriorly sited, particular care should be taken to dissect the nodes fromthesubmental triangle. Both submental triangles should be cleared if the primary is in the anterior midline. Cutting diathermy shouldbe available in all cases. For resecting tumours of thetongue,a CO, laser iseven better. Before proceeding with surgery, the tumour shouldbe reassessed with regard to its site and size. If not previously undertaken, the patient should undergo a thorough upper aerodigestive tract endoscopy to exclude a second primary tumour.

Unless a mandibulectorny is required,the excision of a small intraoraltumourcan usually be undertaken via aperoralapproach. Sixty-five per cent of small tongue lesions occur on thelateralborder and for these a hemi- orpartial glossectorny is necessary (a partial glossectomy being anything less than a formal hemiglossectomy).

Insulated cheek retractors are used to provide goodexposure of theoperative field. Stay sutures should be placed on either side of thetonguetip to provide stability. Theproposed lines of excision are marked out with methylene blue dye, cutting diathermy or the CO, laser. A margin of at least 1cm, and prefer-

3 52

Chapter 49 videaccess to them, care being taken not to disrupt either hypoglossal nerve or lingual artery unless this is necessary in order to clear the tumour. The tongue can then be repaired using Vicryl. It is fortunate thattongue tiplesions are unusual (5%) in that they require a wedge excision of the tip, which will be considerably shortened when thedefect is closed (Fig. 49.4). Small floor of mouth tumours, not invading the mandible, can be dealtwith similarly. A suture is placed through the tongue tip to provide traction over to the uninvolved side. A 1-2 cm margin is marked out andthe excision accomplished perorally, the dissection being taken downto the planes of the genioglossus and mylohyoid muscles. .More deeply infiltrating tumours will requirea‘through-and-through’ resection. If the tumour abuts on but is not fixed to the mandible, then the adjacentperiosteum of the mandible should be taken with the specimen.

Fig. 49.3 Lines of resection for a standard hemiglossectomy.

ably 2cm, should be allowed around the tumour, using frozen-section analysis of the excision margins. 1 Lines of resection for a standardhemiglossectomy are as shown in Fig. 49.3. 2 Using the stay suturesforretraction,thetongue is divided in the midline from the tip back to the midline circumvallate papilla. 3 The tongue tip is elevated to allow simultaneous dissection along the floor of the mouth, just medial to the course of the submandibular duct. 4 The excision line is then taken posterolaterally to the root of the tongue, just anterior to the anterior faucial pillar. It is at this stage that the lingual artery will be located. Carefuldissection will allow sutureligation and division of the artery withminimal blood loss. Virtually all other bleeding can be dealt with using coagulation diathermy or defocused laser beam. 5 Elaborate reconstruction is rarely required. Two or three Vicryl sutures can be placed anteriorly to provide a tongue tip but the entire raw surface of the tongue should not be closed; not only is the risk of a haematoma and airways obstruction considerable but tethering the tonguein this way will also producesignificantlong-term problems witharticulation. Split-skin grafting the defect looks very effective in the short term, but in reality most of the graft sloughs off, providing nothing more than a temporary dressing. Thirty per cent of small tongue tumours occur on the dorsum. It may be necessary to split the tongue to pro-

Marginal mandibulectomy

If atumour isfixed to themandiblebutthere is no clinical or radiological evidence of cortical invasion, then marginal a rather than a segmental mandibulectomy can be performed. The cross-sectional area of the mandible can be reduced by 50-75% before any structural weakness results. There three are basic types of marginal mandibulectomy (Fig. 49.5). While the inferior dental artery may be sacrificed safely during the procedure, itis

Fig. 49.4 Carcinoma of the tongue tip. Adequate resection margins are important.

Surgery f o r Malignant Lesions

important to preserve intact the periosteum over the remaining bone; it is through the periosteal vessels that the mandible will receive its blood supply. The mental nerves should be preserved whenever possible. While an upper alveolectomy can be undertaken by a peroralapproach, an inner-tablemandibulectomy is best carried out through a combined intra-oral/external dissection. l The planned lines of excision are marked out. 2 A stay suture through the tongue tip will allow retraction of this structure. 3 Any teeth at the sites of theplannedosteotomies should be removed. 4 The mucosal and mucoperiosteal incisions are made using cutting diathermy, a scalpel or the CO, laser. 5 The mucoperiosteum is raised for a distance of 3 mm on each side of the incision. With the bone exposed, the osteotomies are then fashioned with a fissure burr. It is important to protect adjacent soft tissues from trauma due to contact with the burr. Malleable copper retractorsare useful forthispurpose. Do notattempt to complete the osteotomy from just one approach; create bony cuts on both sides of the mandible and connect these using the burr. Subsequent covering of the mandible with a flap will be much easier to achieve if the bony edges are ‘cut back’, providing a free edge of intact mucoperiosteum to which a skin or mucosal flap can be sewn. It is not advisable to use an osteotome to make the osteotomies as this technique can result in uncontrolled fracturing of the bone. 6 The soft-tissue part of the dissection is then undertaken perorally. The soft-tissue and bony portions of the specimen should be kept in continuity to allow its correct orientation after excision. 7 After the resection margins have been sent for frozensection analysis, the defect is closed. It is rarely possible to close the defect primarily without significantly compromising tongue mobility. Small defects are best reconstructed using anasolabial, local tongue or radial

3 53

forearm free flap. The nasolabial flap is simple to raise and does not require a functioning facial artery; it is viable even after dividing the artery during a neck dissection. The maindisadvantage of the flap is that it introduces hair-bearing skin into the oralcavity in men.

Large tumours of the tongue will commonly involve the floor of the mouth, and vice versa. Adequate exposure of such tumours can rarely be provided by a peroral approach. Anterior rnandibulotorny

The best approach forlarge lesions which do notrequire a segmental or marginal mandibulectomy is an anterior mandibulotomy. The soft-tissue incision can be incorporated into that used for the neck dissection (Fig. 49.6). The lower lip is pinched firmly on each side of the incision until bleeding from the inferior labial arteries is controlled by diathermy. The mentumof the jaw is then exposed for 1.S cm on each side and astepped mandibular osteotomy is marked out. Two holes are drilled on each side of the osteotomy for the appropriate plates, and the osteotomy is then undertaken using an oscillating saw. It is far more difficult to position the plates correctly if the holes are not drilled until the osteotomy has been completed. Having split the lower jaw, the two halves can then be retracted laterally, using Langenbeck retractors, allowing excellent exposure of the floor of the mouth and the anterior tongue (Fig. 49.7). An appropriate excision is thenundertaken, based on the principles outlined above. Large tumours will often necessitate resection of the adjacent mylohyoid, creating a defect extending through to the neck. Preservation of the contralateral hypoglossal nerve and lingual artery is essential if a functioning tongue remnant is to be preserved. During the excision, keep palpating the tumour to assess the clearance margins. In any event, the deep

margins (tongue musculature) must be sent for frozensection analysis. Segmental or marginal mandibulectomy

Fig. 49.6 Skin incision for an anterior-mandibulotomy approach to the oral cavity.

Fig. 49.7 Resection of an extensive tumour of the mobile tongue via an anterior-mandibulotomy approach.

If a segmental or marginal mandibulectomyis necessary, then such a midline approach is inappropriate unless the tumour involves the anterior floor of the mouth. In such a situation, a visor-flap approach will provide excellent access to the anterior mandibular arch (Fig. 49.8), but should only be performed if the mental nerves are going to be sacrificed as part of the resection. Otherwise the mandible is best approached laterally, after adequate elevation of the superior cervical flap and clearance of the submandibular triangle. Any teeth adjacent to the planned osteotomy sites are removed. The mucosal incisions are then made, but no more soft-tissue work is undertaken intra-orally until the osteotomies have been performed. The lateral aspect of the mandible is exposed down to periosteum, along the length of the planned resection; the lingual surface is only exposed at the sites of the osteotomies. The periosteum is incised and elevated to allow these to be performed using an oscillating drill. The soft tissues of the floor of the mouth and tongue are protectedby passing malleable retractors up through the tunnels created on the lingual face of themandible. As much of the buccoalveolar mucosa is preserved as is possible. Bleeding from the inferior dental artery is stopped using diathermy or bone wax. Theintra-oralpart of the dissection canthen be completed. Large intra-oral defects can only be reconstructed withthe aid of a pedicled myocutaneous(pectoralis major) flap or a free (radialforearm orgroin) flap. While the former has the advantage of speed and simplicity, it is very bulky and will not allowoptimum mobility of the remaining tongue and floor of the mouth. The problem of bulk can be reduced by raising the muscle without a skin paddle; however, the problem of poor tongue mobility remains. The radial forearm flap overcomes this problem and has the added advantage that it can be raised with a segment of vascularised radius for reconstruction of a segmental defect in the mandible. Sensate radial free flaps appear to offer even better intra-oral rehabilitation (Urken et al., 1991). Total glossectomy

A total glossectomy is occasionally the only option for curing a large tongue carcinoma. It should only be considered under the following conditions. 1 The tumour is confined to the tonguemusculature and the operation is oncologically appropriate.

Surgery for ~ a ~ i g n a Lesions nt

3 55

Fig. 49.8 Skin incision for the ‘visor flap’ approach to the anterior and cavity.

2 The patient has alreadybeen treated by external beam or implant radiotherapy. 3 The patient appreciates the inevitable problems with speech and swallowing that will follow surgery. 4 Thepatientappreciates that asubsequentlaryngectomy may well be necessary for intractable aspiration. In any event, it is sensible to carry out a gastrostomy at the time of the glossectomy. Theoperation is best accomplished via ananteriormandibulotomy approach. Mucosal incisions are then made around the perimeter of the floor of the mouth, leaving a good rim of mucosa attached to the lingual plate of the mandible, if tumour clearance allows. This will facilitate easier insetting of the flap. The excison is commenced anteriorly; if the valleculae and tongue base can be preserved then the patientis less likelyto develop aspiration and requireasubsequent laryngectomy. A pedicled or free latissimus dorsi myocutaneous flap provides good bulk and reliability for the reconstruction (Keyserlingk et al., 1989). Suction drainage should be employed whenever the resection extends into the neck. Care must be taken that the suction tubewill not traumatise the vascular pedicle of a reconstructive flap. The wound should be closed with Vicryl and interrupted nylon sutures, or clips. A nasogastric tube should be passed in all patients who have not already had a preoperative gastrostomy.

Postoperative care Drains should remain in situ for at least 48 h-longer if there is significant continueddrainage or a high

risk of fistula formation.Thetracheostomycan be ‘corked’ at 48-72hbut is best left insitu untiloral feeding has commenced and there is no problem of aspiration. Oral feeding should start at 7 days, or 10 days if the patient has previously received radiotherapy. Obviously, it should be delayed if there is evidence of woundbreakdown, soft-tissue infection or flap necrosis.

The most common specific complication is the formation of an orocutaneous salivary fistula. The most common predisposing factors are as follows: 1 previous radiotherapy; 2 poor .preoperative nutritional status; 3 wound dehiscence; 4 reconstructive flap necrosis. Small fistulae in the absence of significant soft-tissue necrosis can be managed conservatively; most will close with time. Appropriate antibiotics should be given and nasogastric feeding continued. If there is significant soft-tissue loss, usually caused by necrosis of the skin flap, or exposure of the great vessels in the neck, then a conservative approach is dangerous. The neck should be re-explored and anydead tissue excised. The defect should be repaired and a pectoralis or latissimus dorsi myocutaneous flap should be inset, with or without a skin paddle. The muscle pedicle provides excellent cover for the vascular tree in the neck, and its ‘external’ surface can be split-skin-grafted if necessary.

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erences and further reading Keyserlingk J, de Francisco J, Stafford N, Rhys-Evans P, Breach N & Mott A (1989) Recent experience with reconstructive surgery following major glossectomy. Arch.Otolaryngol. Head Neck Surg. 115, 331-8. Langdon JD tk Henk JM (eds) (1995) MalignantTumours of the Mouth, Jaws and Salivary Glands. London, Edward Arnold, Chapter 7. Stafford N & Waldron J (eds) (1989) Management of Oral Cancer. Oxford, Oxford University Press, Chapters 9 and 10.

Thawley SE & Panje WR (eds) (1987) Comprehensive Managementof Head and Neck Tumors, Vol. 1. Philadelphia, W.B. Saunders, Chapters 22, 25 and 27. Urken ML, Buchbinder D,Weinberg H et al. (1991) Functional evaluation following microvascular oromandibular reconstruction of the of reconstructed and oral cancer patient: acomparativestudy nonreconstructed patients. Laryngoscope 101, 935-50. Vikram B, Strong EW, Shah J & Spiro RH (1980) Elective postoperative radiation therapy in stages I11 and IV epidermoid carcinoma of the head and neck. Am. J.Surg. 140, 5 8 0 4 .

Surgery for Malignant Lesi of the Oropharynx JOHN WALDRON

indications When considering malignant tumours, the oropharynx is subdivided into four subsites-the tonsil, tongue base, soft palate and posterior pharyngeal wall. The tonsil is the most common site for malignant tumours arising in the oropharynx, followed by the tongue base, and the great majority of these are squamous-cell carcinomas. However, at the time of presentation tumours of the oropharynxoften involve more thanone of these subsites, and it may be difficult to establish the original area from which the tumour has arisen. When planning the treatment, the size of the primary tumourand theextent of nodal involvement are moreimportantthanthearea of theoropharynx from which the primary originated. As a general rule, smaller tumours (T1 and T2)with limited nodal disease (NO or N1) may be treated as effectively with radiotherapy as with surgery. When the primary tumour is larger (T3 and T4) or there are lymph nodes present which are greater than 2-3cm in diameter, then radiotherapy on its own has a much reduced success rate. In these more advanced tumours, surgery, in many cases withplannedpostoperativeradiotherapy, is the preferred treatment option (Stell & Nash, 1987; Stafford et aE., 1989). Surgery is also the only viable option for treatment of a tumour which recurs after primary radiotherapy. The tendency forprimarytumours to have spread across two or more subsites (such as from the tonsil to the tongue base or soft palate) by the time of surgery means that the actual resection performed for the primary tumour will vary from case to case, depending on the extentof the tumour. However, the majority of cases involve the tonsil, and many of the resections can be

considered to be essentially resections of the tonsil with extensions to the tongue base, soft palate or posterior pharyngeal wall. In this chapter the operation forresection of a tonsillar carcinoma, including removal of the ascending ramus of the mandible, will be described in detail, and variations of this technique, together with alternative approaches to deal with tumours arising at other specific sites in the oropharynx, will be considered later.

Preoperative management The most common presenting symptoms of these tumours are: (i) pain, which may be localised to the pharynx or referred to the ear; (ii) alteration of swallowing and speech caused by the primary; and (iii) neck swelling resulting from associated lymphadenopathy, There is often a history of heavy smoking and high alcohol consumption, and this may have led to chronic chest and metabolic problems. A preoperativebiopsy to obtaina histological diagnosis is mandatory prior to treatment planning. If there is doubt about nodalinvolvement, then fine-needle aspiration biopsy may be useful. An examination under anaesthetic (EUA) to accurately assess theextent of the primary disease, and also to look for a synchronoussecondprimary in theupper aerodigestive tract, is also essential. CT and MRI scanning give useful information on the extent both of the primary and of nodal disease, and may show the soft-tissue spread to be more extensive than is obvious on clinical examination. Although CT shows bone involvement more clearly, MRI appears to be better at assessing tumour extent in the soft tissues. Tumours extending to the skull base or extensively in-

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volving theparapharyngeal space are unlikely to be cured by surgery. A plain chest X-ray is necessary to look for pulmonary metastases, or a synchronous bronchial primary, arising as a result of heavy smoking. A full blood count, urea and electrolytes, and liverfunction tests should be performed to ensure that the patient does not have problems resulting from a high alcohol intake or other medical conditions prior to undertaking surgery. Liver ultrasound andlor bone scans may be required to exclude distant metastases.

The oropharynx is that part of the pharynx between a plane at the level of the hard palate above and a plane at the level of the hyoid bone below. It is continuous with the oral cavity anteriorly and includes the soft palate, base of the tongue and both faucial pillars. When considering malignant tumours of this region the most relevantpart of the anatomyis the relationship of the oropharynx to surroundingstructures. An understanding of these relationships allows an appreciation of the possible routes of tumour spreadand helps avoid potential operative complications(Fig. 50.1). The close proximity of the great vessels and in particular theinternalcarotidartery(ICA)must be considered during surgery.These vessels ascend alongside thefascia covering the constrictormuscles which form the wall of

the oropharynx and, if they are not identified and retracted, they may be damaged, particularly when performing the posterior part of the resection. The position of the hypoglossal nerves and lingual arteriesis of paramount importance whenresecting tongue-base tumours, as inadvertent damage to these bilaterally may result in an immobile or non-viable tongue.

Operatiue tee Preparation 1 These procedures should be performed under general should be performed anaesthesia. A tracheostomy to protect the airway during the operation and postoperatively until the swelling has settled. Itis better to performthis at the start of theoperation,asthe endotracheal tube (ET) can then be removed from the surgical field. 2 Broad-spectrumantibiotics, covering bothaerobic and anaerobic bacteria, are given intravenously at the induction of anaesthesia. CO-amoxyclav or a combination of abroad-spectrumcephalosporinwithmetronidazole is suitable. The antibioticsarecontinued intravenouslyuntilnasogastric feeding is established, usually on the second postoperative day. They can then be administered via the nasogastric tube until the fifth postoperative day, when they are stopped unless there is a clinically obvious infection present. 3 Thepatient is positionedsupine ontheoperating

Fig. 50.1 Relationship of oropharynx to surrounding structures: cross-sectional anatomy at the level of the oropharynx. The dotted line indicates the extent of the incision in a standard tonsil commando operation. Note the close proximity of the great vessels.

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Fig. 50.2 Incisions for neck dissection.

table. A support is placed under the shoulders to extend the neck and the head is placed on a head ring. The patient is draped to allow access to the whole of the neck and face on the affected side, as well as to the mouth. In addition, the donor site for the proposed reconstruction should also be prepared at this time. This is possible forall reconstructive options except forthe latissimus dorsi flap, the use of which necessitates the patient being turned on tothe side and redraped during the operation.

In almost allcases a neck dissection will be performed as part of the procedure. The incision will therefore be the appropriate one to give access for the neck dissection (Fig. 50.2). An apron incision, with or withouta vertical extension, will give suitable access. However, if the patient has been irradiated, then two parallel incisions (McFee) may be a better choice, as they give wide exposureinthe neck while avoiding athree-point junction. If adequate access is not obtained using a combination approach via the neck and through the oral cavity, then the neck incision should be extended to split the lower lip inthe midline (Fig. 50.3). This gives wide exposure of the oral cavity and oropharynx. In cases where the mandible is not involved by tumour and a mandibular resection is not necessary, a lower-lipsplitting incision combined with an anterior mandibulotomy gives excellent exposure, particularly for tumours

Fig. 50.3 Extension of incision to split the lower lip in the midline.

that extend forwards into the anterior two-thirdsof the tongue (Fig. 50.4).

The neck dissection is performed first, and the neckdissection specimen is left pedicled on the periosteum of the mandible.

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Fig. 50.4 Anterior-mandibulotomy approach for a tumour of the tongue base which extends anteriorly. The incision is continued along the floor of the mouth and the mylohyoid is divided to allow the mandible to be retracted laterally.

The primary tumour is subsequently resected, using a combined approach externally fromthe neck and perorally. 1 The tumour is first inspected perorally and the extent of the soft-tissue resection and the site of the mandibular osteotomy are planned. The tumour should be resected with a 2cm cuff of normal mucosa and soft tissue surrounding it. Theosteotomyshould be sited approximately 1cm anterior to the anterior mucosal incision inorder to leave a rim of mucoperiosteum to whichthe flap can be suturedwhenthe defect is reconstructed. It is useful to markthe mucosal incisions with methylene blue dye at this stage. This will aid accurate excision, as there will inevitably be significant bleeding into the oral cavity as the soft-tissue excision is being performed. If it is necessary to remove a tooth to allow the osteotomy to be performed, then it is done at this stage. 2 Thenext stage of the excision is approached via the neck. Theupper skin flap is retracted and the periosteum is divided along the inferior border of the mandible fromthe site of the planned osteotomy posteriorly. The periosteum and soft tissues arethen elevated from the lateralaspect of the mandible from the site of the planned osteotomy posteriorly, including the

whole of the ascending ramus. Thisis best accomplished by a combination of sharp and blunt dissection, using a Farrabough periosteal elevator. 3 The periosteum and muscle attachments are elevated from the medial aspect of the mandible at the planned osteotomy site. Malleable copper retractors are placed medial to the mandible and the osteotomy is performed using either an oscillating or a Gigli saw. Bleeding from the cut bone and from theinferior alveolar vessels which run within the mandible is controlled with bone wax or diathermy. 4 The muscular insertions to the coronoid process are freed, using heavy curved scissors. The condyle of the mandible is freed in the same manner. Alternatively, the ascending ramus can be freed by dividing the coronoid process and condyle with a saw and leaving them attached to the soft tissues (Fig. 50.5). S The inferior alveolar vessels are identified entering the medial surface of the mandible at the lingula and are coagulated, or ligated, and divided. 6 The mobilised ascending ramus of mandible is rotated laterally, using a bone hook orheavy bone forceps, and theoral cavity is enteredfromthe neck at the anterior limit of the planned resection. When the initial incision is made through the mucosa from the neck, its site should be checked by looking through the mouth to ensure that it allows adequate clearance of the tumour. The anterior incision is then extended superiorly and inferiorly, using a knife or scissors. The soft tissues are rotated laterally into the neck with the ascending ramus of the mandible, allowing the tumour to be visualised directly (Fig. 50.6).

Fig. 50.5 Site of osteotomy incisions.

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Fig. 50.6 Lateral rotation of the ascending ramus of the mandible. Exposure of tumour after performing the osteotomy and rotating the posterior segment of the mandible laterally.

7 The excision is extended posteriorly along the superior and inferior margins. If adequate exposure is obtained from the neck, then it can be accomplished by thisroute.However,it is often necessary to perform part of the resection perorally, using a headlight for illumination, The excision may need to encompass part of the soft palate, hard palateor posterior pharyngeal wall in order to obtain adequate clearance of the tumour. The soft palate may be excised up to the midline without grossly compromising its function. However, totalor near-total resection of the soft palate creates a significant functional problem and considerable difficulties; hypernasal speech and nasal regurgitation of fluids and food can be anticipated postoperatively in this situation. If part of the hard palate needs to be resected, this is best done using an oscillating saw and osteotome. As the dissection proceeds posteriorly, it is important that the surgeon is aware of the position of the carotid arteries, which areclose to the constrictormuscles of the pharynx and can be inadvertently damaged if they are not protected (Fig. 50.1). As the inferior part of the resection is performed, the hypoglossal nerve and lingual artery should be identified and preserved unless thiswouldcompromisetumour clearance. 8 The posterior part of the excision is then completed by dividing the mucosa and musculature of the posterior pharyngeal wall with curved scissors, while protecting

the carotid arteries. The remaining muscular and ligamentousattachments of the mandible are divided with heavy curved scissors and the specimen is removed. 9 Haemostasis is obtained using a Combination of diathermy and ligation. There is often significant bleeding from the venous plexus in the pterygoid muscles, and a warm moist pack placed in the wound for 5min will control much of the bleeding. The specimen is then inspected to assess the adequacy o f excision, and frozen sections may be sent to the laboratory to check that the margins are clear of tumour. 10 Reconstruction of the defect whenthe ascending ramus of the mandible has been resected is best accomplished with a pedicled myocutaneous flap. The pectoralis major and latissimus dorsi flaps both provide reliable flaps whose bulk fills the defect left after this excision. The pectoralis major is the first choice as it is easier to raise and does not involve turning the patient. However, the latissimus dorsi can be used without causing deformity of the breast and should be considered in female patients. In both cases the flap is raised so that the skin paddle of the flap is sutured to the mucosa and the muscle of the flap to the surrounding pharyngeal muscles. Closure

The flap is sutured using a synthetic absorbable suture, such as 3/0 Vicryl. A large, round, cutting needle facili-

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tates the suturing, which should start with the posterior margin and move anteriorly. This, like the resection, is best accomplished by acombination of external and peroral approaches. A nasogastric tube shouldbe passed under direct vision before the flap is completely sutured in position. The neck should be drained, using either suction, tube or corrugated drains. If suction drains are used, care should be taken to ensure that they do not cross the pedicle of the flap, as direct pressure or suction applied to the pedicle may impair the blood supply. The neck is closed in two layers, withabsorbable sutures to platysma and surgical clips or non-absorbable sutures to skin. The donor site for the myocutaneous flap should be drained with large-bore suction drains. The donor site can be closed primarily, using strong absorbable sutures for the subcutaneous layer and clips or non-absorbable sutures for the skin. The tracheostomy tube shouldbe sutured rather than held by tapes, as these can cause pressure on the pedicle of the flap.

The patient should have NBM for 7 days postoperatively (10 days if the patient has had previous radiotherapy). Feeding is commenced via the nasogastric tube on the first postoperative day. The tracheostomy tube cuff can be deflated on the first or second postoperative day. Thetubecan be removed whenthe swelling has settled such that the tube can be occluded for 24h without difficulty. However, if the resection has been extensive (particularly if a significant tongue-base resection has been performed), aspiration may be a problem, andit may be better to leave thetracheostomy in place until feeding is established.

Fistula formation is more common in patients whohave had preoperative radiotherapy, especially if they are in poor general health. Poor placement of skin incisions, traumatic surgical technique and closure of mucosa and skin under tension may also contribute to fistula formation. A fistula is usually evident within 2 weeks of surgery and often becomes obvious when oral feeding is commenced. If there is some drainage from the neck but

doubt as to whether a fistula exists, a barium swallow (or more simply giving thepatientacoloureddrink, such as blackcurrant juice) will resolve the issue. When the presence of a fistula is established, then it is necessary to inspect the oropharynx to determine the site of the internal openingof the fistula and the state of the soft tissues. It is important to assess the condition of the flap used for the reconstruction, and also to be sure that there is no residual tumour present in the wound edges. If it is not possible to do this with the patient awake, an examinationunderanaestheticshould be carried out. A small fistula tract through otherwisehealthy tissues will usually close spontaneously within 6 weeks. The patientshould be keptNBM and antibiotics given if there is anyobvious soft-tissue infection aroundthe tract. If closure fails to take place asanticipated,a bariumswallowshould be performed to assess the fistula tract. If a small fistula fails to close spontaneously, or if there is a significant soft-tissue defect, the patient should be returned to theatre and the woundexplored and any necrotic soft tissue removed. It is occasionally possible to close a fistula primarily, using local tissues, but it is usually necessary to bring in healthy tissue from elsewhere to achieve closure. The most suitable choice is again usually the pedicled myocutaneous flap (pectoralis major or latissimus dorsi). They have the advantage of being reliable and easy to raise, and the pedicle of the flap affordsgoodprotectionforthecarotidartery, which is at risk of rupture in the presence of a fistula, particularly in an irradiated patient. If there is any tension when theskin of the neck is approximated over the pedicle of the flap, the skin should be left open and the exposed part of the pedicle covered with a splitthickness skin graft.

This is commonly associated with fistula formation, as described above.However,problemswiththeblood supply of the flap, leading to either ischaemia or venous engorgement, may be noted at anearlier stage. If there is doubt about theviability of the flap, the patient should be examined under anaesthetic. The neck incision can be opened to ensure that the pedicle is not twisted or compressed. If the blood supply of the flap is then improved, it can be left and the wound closed using sutures or skin grafting onto the muscle of the flap, so asnotto compress the pedicle. If the viability of the flap cannot be improved,itshould be discarded and a new flap raised and used for the closure.

"

Surgery for aligna ant Lesions of the Oropharynx

The operative technique described above is suitable for resection of a tumour involving the tonsil which has spread to invade the ascending ramus of the mandible. There are other approachesto resecting tumours in theoropharynx,as well asavariation of theabove technique in which the lateral mandibulotomy is used for access butnone of themandible is resected, and these will now be described briefly with.their indications.

The lateralmandibulotomy gives good access to the oropharynx and is aparticularly useful approach for tumours arising from the tongue base which have not spread to involve the mandible (Desanto & Thawley, 1987’).The procedure commences as described in step 1 of Procedure above.The periosteum is then elevated fromboth sides of themandible at the site of the osteotomy.This is usually just posterior to the third molar,althoughthetoothcan be removed and the osteotomy made through its socket if this provides better access. Thetwo plates to be used to close the osteotomy are then temporarily placed in position and the screw holes are drilled prior to the division of the mandible. The osteotomy is made with a saw, and the cut end of the mandible is rotated laterally. The great

Fig. 50.7 Lateral mandibulotomy with lateral pharyngotomy for access to tonguebase tumour. Note retraction of great vessels.

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vessels are retracted posteriorly and the pharynx is entered by making a vertical ‘lateral pharyngotomy’ incision. This incision can be extended inferiorly to give adequate access to the tumour (Fig. 50.7). The tumouris then excised and the reconstruction is completed. The lateralpharyngotomy incision is closed using interruptedsutures(Vicryl)andthe mandible is approximated using the two predrilled plates.

The anterior mandibulotomy approach combined with a lip-splitting incision gives wide exposure of the oral cavity and oropharynx. It is a useful approach for tumours which do not invade the mandible, particularly base-of-tongue tumourswhichextendanteriorlyinto the floor of the mouth. The upper neck incision is extended to split the lower lip in the midline (Fig. 50.3). An incision through thelip at 45” gives a better cosmetic result. The periosteum is then elevated from the mandible for 1.5 cm to either side of the planned osteotomy. This is usually made between thecentral incisors, or between the central and lateral incisors on the side of the tumour. Care should be taken not to elevate the periosteum too far laterally, as damageto the submental nerve may occur. The screw holes are drilled in the mandibleprior to makingtheosteotomy,asforthe lateral mandibulotomy. Once the osteotomy has been made, the incision is continued posteriorly intra-orally

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Chapter 50 along the floor of the mouth on the affected side to the tumour (Fig. 50.4). When the resection and repair have been completed, the intra-oral incision is closed with interrupted sutures and the osteotomy with the predrilled plates. The lip is closed with fine (5/0) interruptedsutures,withgreat care being taken to accurately approximate the vermilion border. One variation of this approach is the median translingual pharyngotomy. This is suitable for the rare situation of a small midline tongue-base tumour. After making the midline osteotomy, dissection is continued by dividing the tongue in the midline (Fig. 50.8). The tumour is then excised and the tongue closed primarily with absorbable sutures. Transhyoid pharyngotomy

Fig. 50.8 Anterior mandibulotomy with a translingual approach to a small midline tongue-base tumour.

Thetranshyoidpharyngotomy is anotherapproach which can be used to excise small tumours of the tongue base. In this approach thehyoid bone is exposed and the muscular and fascial attachments are dissected from its superior surface. The pharynx is entered through the tongue base, which is pulled anteriorly using a grasping forceps to expose the tumour (Fig. 50.9). The tumour is excised and the defect can usually be closed primarily. Care must be taken when using this approach to avoid damage to the hypoglossal nerves and lingual arteries, and to avoid cutting into the tumour when entering the pharynx.

References

Fig. 50.9 Transhyoid Pharyngotomy. The tongue base is pulled forward, exposing the tumour.

Desanto LW & Thawley SE (1987) Treatment of tumours of the oropharynx-surgical therapy. In: Thawley SE & Panje WR (eds) Comprehensive Management of Head and Neck Tumours, Vol. 1. Philadelphia, W.B. Saunders, pp. 699-755. Stafford N, Walsh-Waring GPW & Munro A (1989) Tumoursof the tonsil and retromolar trigone. In: Stafford N & Waldron J (eds) Management of Oral Cancer. Oxford, Oxford University Press, pp. 147-54. Stell PM & Nash JRG (1987) Tumours of the oropharynx. In: Kerr A (ed.) Scott-Brown’s Otolaryngology,Vol. 5. London, Butterworths, pp. 235-49.

Laryngectomy R. T H E 0 G R E G O R

The earliest reference to laryngeal cancer is by Aretaeus, in about AD 100, and 100 years later Galen described a malignant ulceration of the throat and apparently understood the nature and seriousness of laryngeal cancer. However, this knowledge was lost for a time, as there are no knownreferences to laryngeal cancer in the Western literature of the Middle Ages. In 1732 Morgagni clearly described autopsy findings in two cases of laryngeal carcinoma (Silver, 19 81). The first total laryngectomy was carried out on 30 December 1873 by Billroth (Gussenbauer, 1874). Sporadic cases were reported for the next 30 years, but the operation did not gain general acceptance until the pioneering work of Gluck in the early years of the twentieth century (Hollinger, 1975). During the period between the two world wars, widespread acceptance of the procedure did not occur, andmany leading institutions placed theirmajor emphasis onradiationtherapy, which, after 1920, began producing beneficial results (Coward,1921).The lack of enthusiasmfortotal laryngectomy as well as other radical head and neck procedures was understandable in view of the state of surgical and anaesthetic technology, and because it was the preantibiotic era. It was only in the 1950s that the operation gained areputationas effective and safe therapyforadvanced or recurrentcarcinoma of the larynx (Ogura & Bellow, 1952). The subperichondrial operation described by Crowe and Broyles (1938) gave way to the narrow-field operation, as opposed to a wide-field approach by Jackson and Babcock (1931), which was much closer tothe modern laryngectomy, althoughthe hyoid bone and cricoid cartilage were frequently not resected. In the

modernoperation, neck dissection forms an integral part of the procedure, as does removal of the hyoid and cricoid and usually the ipsilateral hemithyroid.The clearance of lymph nodes of the jugular chainsina wide-field approach only constitutes astaging procedure for lymphatic disease in the NO neck.

indications Total laryngectomy is indicated in advanced malignant disease of thelarynx, usually squamouscarcinoma. Occasionally other tumours, such as lymphomas, sarcomas, chemodectomas and tumours of salivary tissue, such as adenoid cystic Carcinoma, occur which may also require this operation. Early tumours, that is, T1 andT2,are effectively treated by radiation in most partsof the world, although partial laryngectomy, either by an endoscopic or laryngofissure approach, may be appropriate. The CO, laser has emerged in recent years as a new surgical tool in resecting early lesions. More advanced lesions, such as T3andT4 tumoursaremore effectively treated by radical surgery in the form of total laryngectomy. There may be controversy in the case of T3 laryngeal carcinomas, which, in some centres, in the absence of clinical nodal metastases, are treated by primary radiation,with surgery held as salvage treatmentforthe radiation failures. This may lead to the conservation of the larynges of about half of the patients (Terhaard et al., 1992). Certainly, in the case of T4 tumours, or those with clinically positive lymph nodal metastases, total laryngectomy is indicated. This operation is also indicated in hypopharyngeal tumours, most of which cannot be resected without also removing the larynx. These

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include tumours of the pyriform fossae, lateral and posteriorhypopharyngeal walls, postcricoid and upper oesophageal areas.

As in all of medicine, history-taking is an essential first step in the assessment of patients. Patients with glottic tumours will usually present early with hoarseness, but patientswithsupraglottictumours present laterwith pain, swallowing difficulty or neck metastases. Similarly, patients with hypopharyngeal cancerpresent later with swallowing problems, pain or neck masses. Smoking of cigarettes is an almost invariable feature, and alcohol abuse canusually be elicited and is more prominent in supraglottic and hypopharyngeal lesions. Clinical examination commences with examination of the mouth, nose and ears as well as the neck for any metastases. The presence of synchronous second primary tumours should also be borne in mind. Mirror examination usually makes the diagnosis, but, in more difficult patients, rigid or flexible telescopic examination is extremely useful. CT (Gregor et al., 1981) andMRI scanning (Castelijns et al., 1987) have become almost essential investigations in all these patients. These modalities are helpful in determining spread of the tumour within the larynx and pharynx, the presence of framework invasion (Gregor& Hammond, 1987) anddirect spread into

surrounding tissues. Also the detection of lymph nodal metastases, especially in the absence of palpable lymph nodes, is important. CT scanning usually indicates positive nodes, with contrast enhancement showing central necrosis by a hypodense area. MRI and, more recently, positron emission tomography (PET)have also added to our ability to interpret neck nodal status (Bailet et al., 1992). All patients should then be subjected to an examination under anaesthetic, where the exact progression of the tumour is assessed and a biopsy taken. At this stage, treatment planning decisions can be made. If operative intervention is planned, standard blood investigations for haemoglobin, leucocytes and electrolytes should be obtained. As these patients commonly have intercurrent disease, ECG, lung-function testing and often a physician’s opinion should be asked for. Psychological and speech therapist’s counselling is advised for these patients preoperatively. When prosthetic voice rehabilitation is planned, which is recommended, this should be explained to the patient. The fact that feeding will be via a nasogastric tube and that no speech will be possible for a least 2 weeks must be made clear.

The larynx is situated in the midline compartment of the neck, deep to the infrahyoid strap muscles. There are two layers of these muscles. The outer layer,

Fig. 51.1 View of the anterior neck, showing the position of the larynx and thyroid gland within the strap muscles.

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terior vascular pedicle. Thethyroidgland is in an inferior andanterior relation to the larynx, and the upper portions of the right and left lobes lie deep to thesternothyroid strap muscles’ attachment to theoblique lines of the thyroid cartilage. The lobes of thethyroid glands intervene between the visceral tubes of pharynx, oesophagus, larynx and trachea, and the carotid sheaths, and the isthmus lies over the second tracheal ring. The ipsilateral thyroid lobe is usually resected with the larynx (see Fig. 51.l).

Fig. 51.2 View of the neck from the right side showing the incisions for total laryngectomy with possibility of a right neck dissection. The stomal opening is shown in the inferior skin flap (see text).

sternohyoid, runs from the body of the hyoid bone to thesternalmanubrium.The deeper layer consists of sternothyroid, which inserts on the oblique line of the thyroid ala, and thyrohyoid, which arises from the oblique line and inserts on the lower border of the greater cornu of the hyoid bone (Fig. 51.1).The inferior constrictor muscles insert laterally on theoblique lines, enclose the pharynx and meet posteriorly in the median raphe. The superior laryngeal artery and vein are accompanied by the internal branch of the superior laryngeal nerve. This neurovascular pedicle enters the thyrohyoid membrane laterally. The artery arises from the superior thyroidartery, and the vein joins thecommon facial vein. The internal branchof the superior laryngeal nerve is sensory to the mucosa of the larynx above, including the vocal cords; theexternalbranch supplies the cricothyroid muscle. The intrinsic muscles of the larynx are supplied by therecurrent laryngeal nerve, which passes upwards in the groove between the oesophagus and trachea, and enters the larynx behind the cricothyroid joint. Theinferior laryngeal artery,a branch of the inferior thyroid artery, accompanies the nerve, and alateral division passes laterally and upwardsto anastomosewithabranch of thesuperior laryngeal artery. In the area of the cricothyroid membrane, deep to the strap muscles, there is a ramification and anastomosis of vessels related to the angle of the thyroid cartilage and the thyroid gland isthmus. This arterialarcade is contributed to by thesuperior and inferior blood supply of the larynx, and communicates with the intralaryngeal vessels, thus constituting an an-

The procedure is carried out under general anaesthesia. The use of perioperative broad-spectrum antibiotic (including anaerobic) cover has made a great difference to the morbidity of the operation. The patientis positioned supine on the table, with the neck extended and in an anti-Trendelenburg (head raised) position to minimise venous engorgement. The usual incision is a modification of the GluckSorenson superiorly based flap, in that a much widerbased flap is used, so that, if a neck dissection is to be performed, an extension over the clavicle is all that needs to be added, on one orboth sides (Fig. 51.2). The incision is made through skin, subcutaneous tissue and the platysma muscle, and the platysma is included in the raised skin flaps. When a neck dissection, either radical, modified or regional, is to be performed, this is done first. At least one jugular vein must be preserved. 1 The laryngeal dissection commences with the incision of the infralaryngeal strap muscles, using the knife or electrocautery, the inferior thyroid arteries are exposed and, on the side of the lesion, tied and cut. 2 Next thesuprahyoidmusculature is severed, using electrocautery. Thismanoeuvre allows considerable mobility early in the procedure (Fig. 51.3). 3 On the side of the lesion, the thyroid lobe is to be resected, and so this thyroid lobe is now mobilised from the carotid sheath, and the superior thyroid artery and middle thyroid vein are ligated and cut (Fig. 5 1.4). 4 Thethyroidisthmus is now exposed and divided, between haemostats, and oversewn with absorbable suture material. Thecontralateralthyroid lobe is now dissected off the larynx, using electrocautery because of the bleeding due to the rich anastomotic arcade mentioned above. This step is completed by dissecting the superior laryngeal artery away from the larynx under the cover of theattachment of sternothyroid to the oblique line. Thissteptherefore ideally preserves the

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Chapter 51 cautery, the attachment of the inferior constrictor muscle is severed just in front of the posterior edge of the thyroid cartilage on the opposite side to the tumour. Normally the pharynxis entered above the hyoid, which is grasped with a heavy tissue forceps. Care is taken not

Fig. 51.3 View of the neck from the right showing the initial steps in mobilising the larynx for total removal.

upper and lower thyroid pedicles (Fig. 515 ) . 5 The superior laryngeal artery and nerve can now be tied off on both sides, and the mobilisation of the hyoid bone cannow be completed, by severing theattachments of the greater and lesser cornua. The attachments of the greater horns of the thyroid cartilage are also severed at this time. 6 The larynx is now only attached by the inferior constrictor, the trachea and its mucosal attachments. The next steps are dictated by the natureof the lesion, which should be approached in such a way that wide excision of thetumour is accomplished. Whenatumour is known toinvade the tongue base, the pharynxis opened laterally, to ensure that the lesion is excised under direct vision. If there is no subglottic extension, the tracheostorne can now be fashioned. 7 The trachea is usually severed between the second and third cartilaginous rings; it is important for the posterior tracheal wall not to be mobilised off the oesophagus. The tracheostome shouldusually be fashioned in a separate opening in the lower skin flap (Fig. 51.2). At this point, the endotracheal tube (ET) is withdrawn by the anaesthesiologist and a tube is passed by the surgeon, through the skin opening and into the lower trachea. One or two anchoring sutures are made between the anterior trachea and the skin opening. The larynx can now be dissected out in a leisurely way, with maximum mobility and under excellent vision. Using electro-

Fig. 51.4 View of the neck from the right showing the stage of the thyroid isthmectomy, and mobilisation of the left thyroid lobe from the larynx and trachea. Internal jugular vein not shown, as seen in a right radical neck dissection.

Fig. 51.5 View of the neck from the front, showing the left thyroid lobe mobilised off the larynx, preserving its blood supply; the right lobe, on the side of the tumour, remains applied to the larynx. (Internal jugular veins not shown.)

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laryngeal excision inferiorly and to ‘peel’ the organ superiorly, while dissecting from below. The pharyngeal repair is the next stage, but, before it is commenced, a nasogastric tubemust be advanced down the oesophagus, unilateral a pharyngeal neurectomy should be performed, and a self-retaining voice prosthesis, such as the Provox (Hilgers & Schouwenburg, 1990) voice prosthesis, should be inserted. This will be discussed in more detailat the end of this chapterinthe section on Long-term effects of laryngectomy. Pharyngeal neurectomy

Usually at least three major branches of the pharyngeal plexus can be identified when dissecting right up to the skull base. These are severed by electrocautery, which effectively demonstrates their innervation of the pharyngeal musculature. This is usually done on the same side as the tumour and the thyroid gland lobectomy. Fig. 51.6 View of the neck fromthe left, showingthe severing of the inferior constrictor from the thyroid cartilage, the division of the trachea and further mobilisation of the hyoid bone.

to enter the pre-epiglottic space and, once the epiglottis is identified, it is grasped by an Allis tissue forceps. Using suction and scissors, the aryepiglottic folds are followed down and posteriorly, exposing the laryngeal vestibule. Once the exact extent of the tumour is seen, the constrictor fibres on the same side are also severed (Fig. 51.6). 8 The larynx is now ‘peeled’ forwards, while the surgeon carefully dissects it away. Good suction, light and assistance are essential at this stage, while the surgeon stands above thepatient’s head, facing hidher feet. Once the mucosal excision line around the tumour is complete, the mucosa of the pyriform fossa on the opposite side can be dissected loose from the larynx, and the mucosal excision line continued over the postcricoid area (if there is no tumour involvement). The posterior tracheal wall is now dissected away from the oesophagus to the point at which it has already been transected, thus completing the laryngeal extirpation (Fig. 51.7’). Although this approach may be regarded as standard, it should sometimes be modified by preoperative knowledge of the extent and localisation of the tumour. Thus, when dealing with a hypopharyngeal tumour, the opposite pyriform ‘Ossa is entered in Order to have control in excising the larynx. In supraglottic tumours, with tongue-baseinvasion, one might choose to start the

Closure

Closure can be accomplished by continuous or interrupted sutures, but shouldalways be meticulous, invert-

Fig. 51.7 The neck from the left showing the mucosal excision line; the larynx is ‘peeled’ inferiorly, while the mucosal excision is done from above, using good light and suction.

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Chapter 511

ing the mucosa. A second submucosal layer is used, and the muscle layer is loosely 'tacked' over the repair. The remaining thyroid lobe should never be sutured across the repair, since it may produce swallowing and speech difficulties in the rehabilitation of the patient. Bilateral suction-drain catheters,which should be soft, areplaced lateral to the pharynx oneach side, care being taken not to apply suction directly onthe repair. The skin is sutured intwo layers. The sutureline may be sealed with antibiotic ointment, or with povidone-iodine, and thin strips of plaster. No heavy dressings are needed, and indeed they are contraindicated because they tend to mask any haematoma formation and may obstruct the stoma. Tracheostome constructfion

The best results are obtained whenit is possible to make thestomainthe inferior skin flap, using aseparate fenestra in the skin (see Fig. 51.2). This may be round, but experience has shown that themost effective shape is crescentic. The trachea should be transected at a slight angle, making the posteriorlip more rostral. An angle of between 20" and 30" is optimal; if greater, the stoma becomes unacceptably large for the patientto effectively occlude for prosthetic speech. The suture should ensure that there is skin cover over the bare edge of the trachea, so that no cartilage is exposed. Exposed cartilage may lead to perichondritis, infection, granulations and eventually stenosis (Verschuur et al., 1996).

Postoperative management Unless the patient is to be ventilated in the immediate postoperative period, no tracheostomy tube is needed. The use of stoma tubes or buttons is controversial, but should not be needed, as the trachea hasbeen sutured to the skin. Any type of tube or cannula is only needed when there is bleeding, swelling or oedema which may occlude thestoma. The use of these tubesshould be limited as much as possible, since they may cause erosion of the mucocutaneous edges and lead ultimately to stenosis. Humidification of inspired air is of paramount importance, so that no crust formation takes place and secretions remain liquid. Suctioning by nursing staff must be monitored carefully and should be gentle, not producing erosions of the mucosa, which also promote crust formation. The patient should be encouraged to cough up thesecretions, so that they are suctioned at the stomal edge. In the early phases, it is helpful for skinprotective agents, such asTegaderm, Stomahesive or Duoderm, to be placed over the skin surrounding the

stoma. All these measures are directed at achieving firstintention mucosa to skin healing of thewound and minimising the complication of stomal stenosis.

~omplication Complications may be divided into immediate or operative, intermediate or postoperative and late. Operative

Operative complications are those of any comparable majoroperation, such as bleeding, air embolism or pneumothorax.Withcompetent surgical technique, these are very rare indeed. Postoperative

These are usually divided into general and local. General complications are again those of any major operation, such as pulmonary infection, urinary infection (in association with catheterisation)and septicaemia, cardiac or neurological. The rate of pulmonary embolism is lower in head-and-neck surgery than in chest or abdominal surgery, but theuse of low-dose subcutaneous heparin is recommended. Local complications are mainly related to bleeding or to pharyngeal repair leakage, both of which may lead towound breakdown and fistula formation. Broadspectrumantibiotic cover (includinganaerobic) and meticulous repair of the pharynx, with careful haemostasis and effective suction drainage, should prevent the complication of fistula. Chylous leakage and carotid 'blow-out' are complications of neck dissection, with or withoutpharyngeal breakdown, and will not be considered further here. Skin necrosis may occur,particularly in irradiated patients and with ill-advised incisions. Airway obstruction may cause some concern, but, as mentioned above, when the trachea is meticulously sutured to skin, preferably in a separate opening in the lower skin flap, and there is no excessive swelling or exceptional bleeding, there should be no fear of this. It is, however, very important that the patient should be nursed in an intensive, or high, care facility for the first 24-48 h. Warm moistened inspired air should be provided by a tracheostomy mask, thus preventing crust formationand obstruction. Rarely, apatientwitha short, thick or fat neck may require a postlaryngectomy cannula to avoid obstruction.This is usually only needed fora few days. Bulky dressings should be avoided since they may obstructthestomainadvert-

Total Laryngectomy ently. Cuffed tracheostomy tubes should be limited to patients who need postoperative ventilation. They do not help with the control of secretions, and may lead to excessive irritation and coughing. Most fistulae close spontaneously with careful nursing and delay in feeding the patient by mouth, but some may persist and require closure by local procedures, by repairing the innermucosa and outer skin or by local or distant flaps. In large pharyngocutaneous fistulae, the pectoralis major mycutaneous flap is of major importance. By applying split skin to the muscular surface, two epithelial layers are achieved, with the chest skin sutured to the pharyngeal mucosa.

These are: tumourrecurrence, particularly stomal recurrence, and stomal stenosis. Dysphagia and difficulties with speech rehabilitation will be considered under Long-term effects of laryngectomy. Hypothyroidism andhypoparathyroidismarealso late complications, particularly in patients who have also been irradiated. Stomal recurrence

This is a dreaded complicationsince it is associated with a very poor prognosis. Predisposing factors are related to theextent of thetumour,particularlysubglottic spread with paratracheal nodes, and the presence of a prelaryngectomy tracheostomy (Stell & van den Broek, 197’1).More recently, the validity of this contention has been questioned, suggesting that it is not the tracheostomy, but the size of the tumour that is important in nce. Nevertheless, tracheostomy remains an undesirable procedure with laryngeal cancer, whetherthepatient is to be treated by radiation or laryngectomy. For this reason ‘emergency laryngectomy’ (laryngectomy en c h a d ) has been advocated to avoid thepossibility of this complication.Alternatives to emergency laryngectomy may be to resect tumour with theCO, laser to provide an interim airway, or to perform a cricothyroidotomy (coniotomy), as the tract of this procedure canbe easily and widely resected with the larynx. Radical excision of the stoma,including an upper mediastinal dissection and pectoralis major myocutaneous flap reconstruction, offers the only chances of cure, but the operative mortality is high and 5-year survival remains poor (Biller et al., 1980). Stomal stenosis

Stomal stenosis has no accepted definition in the litera-

37 I

ture, but there is some rationale for the concept that a stoma with a cross-sectional area less than that of the glottis at rest may be considered too narrow (Gregor & Hassman, 1984). Thebest way to avoid stomal stenosis is the use of sound surgical principles with the initial construction (see above). Other factors predisposing to stenosis are those that will result in secondary healing with scar formation. Suturing under tension, infection, perichondritis and trauma, which may be produced by injudicious suctioning or the use of ill-fitting cannulas, are significant.

laryngectomy The physical and psychosocial consequences of total laryngectomy must be takenintoaccountwhen performing the operation. Good voice rehabilitation is an essential step in the rehabilitation of the patient (Hilgers & Balm, 1993). Apartfrom voice rehabilitation,the presence of a stoma, sputum production and coughing, and the need for forced expectoration all contribute to psychological distress (Hilgers et al., 1990). The need for humidification of the inspired aircan be demonstrated by the improvement of these symptoms by the use of heat-moisture exchangers (Hilgers et al., 1991).

Bailet JW,Abemayor E, Jabouw BA, Hawkins RA, H0 C & Ward PA (1992) Positron emission tomography-a new precise imaging modalityfor detection of primary head and neck tumours and assessment of cervica lymphadenopathy. Laryngoscope 102, 281-8. Biller HF, Krespi YP, Lawson W & Baek S (1980) A one-stage flap reconstruction following resection stomal for recurrence. Otolaryngol. Head Neck Surg. 88, 357-60. Castelijns JA, Kaiser MC, Valk J, Gerritsen GJ, van Hattum H H & Snow GB (1987) Magnetic resonance imaging of laryngeal cancer. J.Comp. Assist. Tomogr. 11, 134-40. Coutard H (1921) Roentgentherapy of epitheliomas of the tonsillar Am. J. region, laryngopharynx and larynx from 1920 to 1926. Roentgenol. 28, 313-31. Crowe SJ & Broyles EN (1938) Carcinoma of the larynx and total laryngectomy. Trans. Am. Laryngol. Assoc. 60, 47-68. Gregor RT & Hassman E (1984) Pulmonaryfunction testing in postlaryngectomy patients, related to stomal size. Acta Otolaryngol. (Stockh.) 97, 177-83. Gregor RT & Hammond K (1987) Framework invasion by laryngeal cancer. Am. J.Surg. 154, 452-8. Gregor RT, Lloyd DM & Michaels L (1981)Computed tomography of the larynx: a clinical and pathologic study. Head Neck 3, 28496. GussenbauerC (1874) Ueber die erste durchTh. Billroth am Menschen ausgefuhrtekehlkopf-extirpationund die anwendung eines kunstlichen kehlkopfes. Arch. Klin. Chir. 17, 343-56. Hilgers FJM & Balm AJM (1993) Long term results of vocal rehabili-

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tation after total laryngectomy with the low-resistance, indwelling ProvoxTMvoice prosthesis system. Clin, Otolaryngol. 18, 517-23. Hilgers FJM & Schouwenburg PF (1990) A new low-resistance, selfretaining prothesis (ProvoxTM) for voice rehabilitation after total laryngectomy. Laryngoscope 100, 1202-7. Hilgers FJM, Ackerstaff AH, Aaronson NK, Schouwenburg PF & van Zandwijk N (1990) Physical and psychosocial consequences of total laryngectomy. Clin. Otolaryngol. 15, 421-5. Hilgers FJM, Aaronson NK, Ackerstaff AH, Schouwenburg PF & van Zandwijk N (1991) Theinfluence of a heat and moisture exchanger (HME) onthe respiratory symptoms aftertotal laryngectomy. Clin. Otolaryngol. 16, 152-6. Hollinger PA (1975) A century of progress o f laryngectomies in the northern hemisphere. Laryngoscope 85, 322-32. Jackson C & Babcock W (1931) Laryngectomy for carcinoma of the

larynx. Surg. Clin. North Am. 11, 1207-27. Ogura JH & Bellow JA (1952) Laryngectomy and neck dissection for carcinoma o f the larynx, Laryngoscope 62, 1-52. Silver CE (1981) Surgery for Cancer of the Larynx, 1st edn. New York, Churchill Livingstone, p. 1. Stell PM & van den Broek P (1971) Stomal recurrence after laryngectomy: aetiology and management. J.Laryngol. Otol. 8 5 , 131-40. Terhaard CHJ, Hordijk GJ, van den Broek P et al. (1992) T, Laryngeal carcinoma:a retrospective study of the Dutch Headand Neck Cooperative group: study design and general results. Clin. Otolaryngol. 17, 393-402. Verschuur HP, Gregor RT, Hilgers FJM & Balm AJM (1996) The tracheostoma in relation to prosthetic voice rehabilitation. Laryngoscope 106, 111-15.

Vertical Partial Laryngect

Y

KERRY D. OLSEN

moval of one vocal cord through an external incision. No thyroidcartilage is removed in this procedure. ‘Frontolateralpartial laryngectomy’ (‘vertical partial laryngectomy’) refers to excision of aportion of the laryngeal cartilage, generally with removal of one vocal cord or aportion of theoppositecord (orboth). ‘Hemilaryngectomy’ is used to describe the removal of half of the larynx, including one side of the thyroid ala, the arytenoid and the vocal cord. The cricoid cartilage is preserved. Theanterior-commissureprocedure removes aportion of thethyroid cartilage overlying the anterior portionof each vocal cord. ‘Vertical partial laryngectomy’ is also used as an all-encompassing term that includes laryngofissure-cordectomy, hemilaryngectomy and all other open procedures performed for early glottic cancer.

Introduction Carcinoma of the larynx is the most common head and neck malignancy treated by otolaryngologists. However, the treatment of early glottic carcinoma is still a matter of controversy. The treatment options include endoscopic removal, radiation therapy and open surgical procedures. This chapter focuses on glottic tumours for which partial vertical laryngectomy is the selected treatment. Stage T1 glottic tumours comprise a spectrum of disease, i.e. not all T1 tumours are the same. Some are barely invasive and are small enough to be removed with biopsy. These tumours are grouped with lesions that involve theanterior-commissure region and that extend close to or invade the thyroid cartilage. Kirchner (1984, 1989) has clearly shown the problems with tumour invasion in theanterior-commissurearea. The appropriate treatment for anterior-commissure cancer is debatable; however, the main indication for performing a partialvertical laryngectomy is tumour involvement of the anterior-commissure area or anterior portion of the true cord. At the Mayo Clinic, open operations have accountedfor 55% of the initial treatmentfor early glottic cancers. Endoscopic removal has been used in 25% of cases and radiation therapy in 20% (DeSanto, 1987). Withearlier diagnosis, the percentage of tumours that can be treated endoscopically should increase. The terminology used for open laryngeal operations can be confusing. ‘Laryngofissure’ and ‘thyrotomy’ refer to division of thethyroid cartilage, generally in the midline, to expose the laryngeal lumen. ‘Cordectomy’ refers to the removal of a vocal cord,whichcan be performed endoscopically orthrough laryngofissure. Therefore, laryngofissure-cordectomy results in the re-

Surgical indications General

The main indicationis a large, invasive T1 carcinoma on a mobile vocal cord involving the anterior-commissure area. Other important factors include the patient’s sex, age, occupation, lifestyle, ability to travel to treatment centres and reliability of follow-up. Ultimately, the patient’s own desires must be paramount. Pathology

The histological features of the tumour and extent of invasion are important factors relevant to the performance of an open laryngeal procedure for early glottic cancer. In general, when in situ carcinomaalone is found, it is treated endoscopically and is not an indica373

tionfor an openoperation. Anterior-commissure involvement by carcinoma in situ, however, has been reported to result in conversion to invasive squamous-cell carcinoma (SCC) in 92% of cases compared with 17% of lesions limited to the midportion of the mobile vocal cords (Chiesa et al., 1991). When in situ disease in the anterior-commissure cannot be effectively ablated endoscopically, radiation therapy shouldbe considered. Also, early microinvasion of the glottic larynx can generally be managed endoscopically; it does not usually require an open operation (Crissman et al., 1988). In general, open laryngeal procedures are performed for invasive carcinoma and not for in situ disease, dysplasia or early microinvasion. Exceptions can occur because of difficulties with exposure endoscopically, tumour location orrecurrence after previous endoscopic removal. In addition, areas of invasive carcinoma that may require vertical partial laryngectomy often coexist with in situ disease on the opposite cord. This mucosal component can be removed in an open operation, with preservation of the underlying cordal structures and control by examination of frozen sections. Results of the examination of frozen sections of thetumourmust be available in order to perform any vertical partial laryngectomy operation. ca

Invasive cancer that is limited to the midcordal area, with retained cordal mobility and absence of involvement of the anterior quarter of each vocal cord, can generally be removed with an endoscopic procedure. However, treatment the of invasive anteriorcommissure cancer with endoscopic removal has been associated with a high rate of local recurrence. Laser removal of tumour in this area has also been associated witha high rate of recurrence, often necessitating laryngectomy (Krespi & Meltzer, 1989; Chiesa et al., 1991). In contrast, open operations have an associated lowrate of local recurrence for invasive anteriorcommissure tumours. An openoperation provides a wide, safe, anterior margin by going beyond the thyroid cartilage to establish oncological safety (Ossoff et al., 1985; Olsen et al., 1993). The tumour canextend from the arytenoid on one side to the anterior third of the opposite vocal cord and still be removed by a vertical partial operation. Contralateralvocal-cord involvement beyond theone-thirdarea generally requires the removal of too much cordal tissue to support an adequate voice or a larynx free from stenosis or aspiration. When there is extensive bilateral invasive disease, the preferred treatment option is generally radiation therapy.

ic

Vertical partial laryngectomies are generally used only for T1 glottic tumours. The glottis is defined as an area withextension to the midventricle and to the region from 5 mm to 1cm beneath the true cords.Small degrees of subglottic or supraglottic extension can be managed effectively with an open laryngeal procedure (DeSanto &;Vaughan, 1991). Fixation of the vocal cord implies that the tumourinvolves the intrinsic laryngeal musculature and theparaglottic space. After this occurs, the tumour has access through the paraglottic region down to the level of the cricoid cartilage. Vertical partial laryngectomy then becomes oncologically unsound unless the cricoid cartilage is removed. Removal of the bulk of the cricoid cartilage usually necessitates a permanent stoma. Therefore, stage T1 glottic cancer can be managed withvertical partial laryngectomy if the cancer extends from the arytenoid to the opposite one-third of the vocal cord, with retention of mobility of the cord.

1 Tumours that extend posteriorly to involve the bulk of the body of the arytenoid should not be treated with vertical partial laryngectomy. 2 The tumour should not involve the subglottic larynx. Extension of the tumour more than 1cm beneath the truecords is one of themajor causes for failure of vertical partial laryngectomy. 3 Involvement of the supraglottic larynx. Invasive tumour extension in the false vocal cord, i.e. transglottic tumours, should not be managed with a vertical partial operation. Involvement of the supraglottic larynx gives ready access to the rich lymphatic vessels in the supraglottic area, and tumour extension can occur rapidly in this region. Supraglottic tumours should be treatedwithhorizontaloperations, i.e. supraglottic laryngectomy, when appropriate and not with vertical procedures because vertical operations do not encompass the area in which supraglottic tumours can spread readily.

The surgical anatomy of the larynx pertinent to vertical partial laryngectomy is well known by all otolaryngologists; however, certain anatomical structures are important in the performance of the variations of vertical partial laryngectomy (Schwartz et al., 1963). The Delphian lymph node, or prelaryngeal node, is located in the fascia above the thyroid isthmus and lies

between the cricoid and thyroid cartilages. This node should be submittedforpathologicalstudy. Usually, there is only onelymph node, but two to four nodes may be grouped together. Other midline nodes located anterior to the trachea are called the ‘subdelphian nodes’. They are generally foundbeneaththeborder of the thyroidisthmus andare less constant in location. The Delphian lymph node receives lymph flow from the upper and anteriorportions of both lobes of the thyroid gland andfrom thethyroid isthmus. Italso receives efferent lymph flow from the larynx. The subepithelial space of the true cords containsfew lymph vessels, and metastasis fromtumours confined tothetrue cords is rare.However,tumourextension to theanterior commissure can spread through a small anterior lymphatic pathway that pierces the cricothyroid membrane and drains to the Delphian node. The subglottic larynx also has lymphatic vessels that pierce the cricothyroid membrane anddraininto theDelphian node. When metastasis is found in the Delphian lymph node from glottic carcinoma, the recommended treatment is ipsilateral neck dissection (Olsen et al., 1987). Accurate identification of the midline of the larynx is also important in performing laryngofissure via an external approach. The thyroid notch is often asymmetrical and so is not a reliable landmark for the midline. However, a vein in the cricothyroid membraneis immediately beneath the midpoint of the vocal cords, and its location is a fairly constant landmark for thelevel of the anterior commissure. The anterior-commissure area contains Broyle’s ligament, which is attached anteriorly to the thyroid cartilage inthe midline. In this area,there is no internal perichondrial layer and thus less protectionagainst tumour invasion. No surgical plane exists inside the larynx to separate soft tissue easily from the anterior thyroid cartilage. Bailey (1985)states that adequatesurgical excision of cancer in this area must include removal of adjacentstructures, such asthe overlying thyroid cartilage.

invasive cancer,the neck is prepared anddrapedto permit possible laryngectomy or neck dissection. The patient is placed in a slight reverse Trendelenburg position, and routine tracheostomy is performed inferior to thethyroid isthmus; general anaesthesia is continued through this site. is

Several skin incisions can be used to perform a vertical partial laryngectomy. Generally, aseparate transverse incision is made over the midportion of the thyroid ala and extendedfromonesternomastoid muscle to the other. Neck flaps are then elevated in a subplatysmal plane to the level of the hyoid bone and to beneath the cricoid cartilage. Thestrap muscles are divided in the midline and retracted.TheDelphian lymph node is then identified, removed and submitted for frozensection pathologicalstudy. At this point,the midline vein can be seen in the region of the cricothyroid membrane. The various vertical partial laryngectomy opera-

Operative techniq Preparation

The patient is brought to theoperatingroom and intubated with asmall endotracheal tube (ET),generally a 7-mm (no. 5) tube.Thelarynx is then assessed by direct laryngoscopy. A biopsy specimen of the larynx is takenand submittedfor frozen-section pathological examination. The exact extent of the tumour is visualised and confirmed pathologically. After confirmation of

Fig. 52.1 (a) Lesion (white area) appropriate for laryngofissurecordectomy operation. (b)Incision used for all open laryngeal procedures. (From Olsen, 1992. By permission of Mayo Foundation.)

Fig. 52.2 (a) Identification of Delphian node. (b) Midline cartilage incision. (From Olsen & DeSanto, 1990. By permission of Mayo Foundation.)

Fig. 52.3 (a) Division of cricothyroid membrane. (From Olsen & DeSanto, 1990. By permission of Mayo Foundation.) (b) Larynx opened at midline. (From Olsen, 1992. By permission of Mayo Foundation.)

tions can now proceed'(Fig. 52.1). An alternative to the transverse incision is a small apron incision raised at the level of the tracheostomy site or a midline vertical incision, which can be very effective for exposure and cosmesis in an older person with redundant anterior platysma1 folds.

Specific operations Laryngofissure=cordectomy

After retraction of the strap muscles and exposure of the thyroid cartilage, a paralysing agent is given by the anaesthetist. Laryngeal hooksarethen placed inthe superior portion of each thyroid ala and used to retract the larynx in a superior and lateral direction. Next, an oscillating saw is used to make a cutin the midline of the

cartilage (Fig. 52.2). The vein found in the cricothyroid membrane is a useful landmarkfordeterminingthe midline position of this incision. The surgeon then uses a headlight and divides the thyroid ala. With traction, the cartilage will separate easily without entering the laryngeal lumen. A small cut is then made in the cricothyroidmembranewitha long-handled knife (Fig. 52.3). The incision is extended superiorly. Small skin hooks are placed in each side of the incision and advanced superiorly by the surgeon and an assistant. The anterior commissure can be identified by notingthe yellow end of Broyle's ligament and by direct observation from below. The larynx is opened in the midline, dividing the anterior commissure and extending the incision into the pre-epiglottic space. The larynx is then opened like a book. Direct inspection of the tumour should ensure that the

Vertical Partial Laryrzgectomy

3 77

Fig. 52.4 (a) Dissection of thyroid perichondrium. (b) False-cord and subglottic incision. (From Olsen & DeSanto, 1990. By permission of Mayo Foundation.)

cancer does notinvolve the most anterior portiono f the vocalcord.Thetumourcanbe easily visualised. A periosteal elevator is used to dissect the intrinsic laryngeal musculature and soft tissues from the inner thyroid perichondrium. Establishment of a correct plane can be ensured by noting the smoothfeel o f the elevator against the thyroid perichondrium. If the elevator has a rough feel to it,the dissectionis too deep and haspassed beneath the thyroid perichondrium against the cartilage. Dissection in this plane can lead to perichondritis, especially in a previously irradiated larynx. With the patient still paralysed, a malleable retractor is inserted to protect the opposite normal vocal cord. With a cautery, cuts are then made through the inferior portion o f the false cord or in the ventricle and in the subglottic region (Fig. 52.4). The vocal cord is grasped at its anterior extent, and dissectionismadeprogressively back toward the vocal process of the arytenoid. The final attachment o f thevocalcordtothevocalprocess o f thearytenoid is divided with curved Panzer scissors (Fig. 52.5), andfrozen-sectionevaluation of all marginsis then obtained. Vertical partial laryngectomy (frontolateral procedure)

The most common open operation for early glottic carcinoma is performed to treat tumours that involve the anterior-commissure region. A safe anterior margin can be ensured only by removing a portion o f the thyroid cartilageadjacent to thelocation o f thecancer.The

Fig. 52.5 (a) Division of vocal process of the arytenoid. (From Olsen & DeSanto, 1990. By permission of Mayo Foundation.) (b) Defect after cordectomy. (From Olsen, 1992. By permission of Mayo Foundation.)

amount o f cartilage removed is dictated by the extent of the tumour and is almost always less than half of one hemithyroid cartilage (Fig. 52.6). As stated above, the cancer can involve one vocal cord and cross the midline to involve not more than the anterior third o f the opposite cord. The initialstage o f the operation is identical to

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Chapter 52

Fig. 52.6 (a) Lesion (white area) suitable for frontolateral partial laryngectomy (vertical partial laryngectomy). (From Olsen, 1992. By permission of Mayo Foundation.) (b) Second cartilage cut. (From Olsen & DeSanto, 1990. By permission of Mayo Foundation.)

that described for laryngofissure-cordectomy. A scalpel with a no.15 blade is used to make an incision along the superior and inferior borders of theexternalthyroid cartilage. The external perichondriumis reflected off the thyroid cartilage from the initial thyrotomy site back to approximately the halfway point on the side ipsilateral to the tumour. The perichondrial flap is often useful in later closure. The initial thyrotomy incision throughthethyroid cartilage is made approximately 1cm from the midline on the side oppositethetumour. An incision is then made in the cricothyroid membrane with a long-handled no. 15 blade. Skin hooks are placed on each side of the incision and, by using a headlight and working from below, the surgeon connects the incision in the cricothyroid membrane with the thyrotomy cut. With direct visualisation from below, cuts are made progressively through the true and false cords just beyond the level of the tumour. The amountof vocal cord removed on theopposite side is dictated by theextent of the

tumour. This will have been confirmed earlier at the time of direct laryngoscopy. The larynx is again opened like abook and thetumour is inspected. A second cartilage cut is now madeon the side of the tumour. The amount of cartilage excised depends on the size of the lesion, but it generally involves about one-third of the thyroid ala on the ipsilateral side. Again, laryngeal hooks are placed on each side of the cartilage cut and the incision site is marked with an ink pen and divided with an oscillating saw. Retraction on the cartilage permits easy separation of the cartilage without entering the soft tissues of the larynx. The anterior thyroid cartilage to be removed is now grasped with forceps. A skin hook isused to retracttheposteriorportion of the thyroidala, and thesoft tissues are bluntly elevated fromthe remaining posteriorthyroidperichondrium (Fig. 52.7). Thesoft tissues are elevated back to the level of the arytenoid. A malleable retractor is placed to protect the opposite vocal cord. With a cautery, cuts are made in the subglottis beneath the tumour and in the ventricle or through the false cord and extended up and around the free anterior thyroid cartilage. Again with cautery, the deep soft tissue is progressively thinned back toward the vocal process and, under direct vision, Panzer scissors are used to divide the final posteriorattachment of thetumour, generally throughthe vocal process of thearytenoid (Fig. 52.8). The specimen is submitted for pathological examination of frozen sections for confirmation of the margins. Separate margins may also be taken from the patient for oncological security. Anterior-commissure procedure

For tumoursconfined to the anterior-commissureregion alone, a variationof vertical partial laryngectomy can be performed in which only the anterior quarterto third of each vocal cord is removed (Fig. 52.9). The overlying thyroid cartilage is excised to ensure anterioroncological security. Identical exposure of thethyroid cartilage is performed as described above. Skin hooks are placed on each side of the thyroid cartilage and, with an oscillating saw, cartilage cuts are madeon either side of the midline. Again, the amount of cartilage excised is determined by the extent of the laryngeal cancer. The cartilage cuts are made only in the cartilage and do not enter the lumen of the larynx. The cricothyroid membrane is divided with a long-handled no. 15 blade and, under direct vision workingfrom below, the cricothyroid incision is extended up each side into the previously made cartilage cuts. This is done by progressively advancing a skin hook on either side of the incision.

VerticalPartialLaryngectomy

3 73

Fig. 52.7 (a) Separation of laryngeal musculature from the thyroid perichondrium. (b)False-cord and subglottic incision. (From Olsen & DeSanto, 1990. By permission of Mayo Foundation.)

Fig. 52.8 Posterior division of specimen. (From Olsen, 1992. By permission of Mayo Foundation.)

Under direct vision from below, cuts are made through each vocal cord just beyond thelevel of the tumour. The midline section of thyroidcartilageandeachanterior vocal cord are then removed. Frozen-section confirmationofadequate margins is thenobtainedto ensure clearance at the level of the remaining true cords and paraglottic space.

Fig. 52.9 (a) Lesion (white area) suitable for anterior-commissure procedure. (From Olsen, 1992. By permission of Mayo Foundation.) (b)Bilateral anterior-commissure cartilage cuts. (From Olsen & DeSanto, 1990. By permission of Mayo Foundation.)

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Chapter S2 ect

Hemilaryngectomy is also an open laryngeal procedure. It has not been described in this chapter from asurgical technique standpoint because it is rarely performed for early glottic carcinoma.According to the classic description, hemilaryngectomy removes half of thelarynx, including half of the thyroid cartilage and one arytenoid. The terminology used in the literature, however, can be confusing and frequently this formal extent is notmeant in descriptions of ‘hemilaryngectomy’. Hemilaryngectomies have been useful for the rare early lesions that extend back on to thebody of the arytenoid with a mobile vocal cord. Also, this operation may be useful in cases of tumours that impair mobility of the cordwithout complete fixation. For early cordaltumours, hemilaryngectomy provides an oncological margin at the far edge of the posterior thyroid cartilage, where it is least needed. Indeed, if the tumour extends to this portion of thethyroid cartilage, deep-muscle invasion and paraglottic-space invasion should have occurred and the vocal cordshould not be mobile. Therefore, hemilaryngectomy is excessivefor most early growths, and the vocal consequences aftera hemilaryngectomy are worse thanwith theotheropen procedures. In addition, laryngeal reconstruction is essential, and stenosis of the larynx and long-term use of a tracheostomy tube may follow. For the rare posterior cordal T1 tumoursthat involve the body of the arytenoid, the author preserves the superior and inferior anterior ipsilateral thyroid cartilage and removes only

the midcordal and posterior thyroid ala to achieve adequate exposure and oncological security. Preservation of these portions of the thyroid ala assist closure and avoid the need for reconstruction with muscle flaps. Closure

After laryngofissure-cordectomy, no attempt is made to reconstruct the resected tissue. The wound is allowed to heal by secondary intention, and generally a pseudocord develops that is often indistinguishable from a true cord. The main noticeable feature will be loss of cordal thickness. The thyrotomy incision is reapproximated by plating sutures in the thyroid perichondrium or through the thyroid cartilage (passing sutures through the cartilage itself in non-calcified areas or after placing small angled drillholes).The fascia overlying the strap muscles is reapproximated in the midline (Fig. 52.10). A Penrose drain is inserted, and a cuffed tracheostomytube is placed to avoidsubcutaneous emphysema. Next,the neck incision is closed in layers withinterrupted 4 0 chromic sutures deeply and 610 non-absorbable sutures in the skin. A dressing is applied. After partial vertical laryngectomy, a suture is placed to reattach the base of the epiglottis superiorly to the hyoid bone. The remaining true and false vocal cords arereattached to theexternal or internalthyroid perichondrium (Fig. 52.11). The ipsilateral false vocal cord is alsoresuturedanteriorly.This is donewith Vicryl sutures and anchored securely into the remaining thyroid cartilage. If necessary, drill holes can be placed

Fig. 52.10 (a) Reapproximation of the

thyroid cartilage. (From Olsen, 1992. By permission of Mayo Foundation.) (b)Final closure after laryngofissure-cordectomy. (From Olsen & DeSanto, 1990. By permission of Mayo Foundation.)

Vertical Partial Laryngectomy in the thyroidcartilage. If possible, sliding advancement mucosal flaps are used to cover any bare cartilage aver the arytenoid. Thiswill decrease subsequent granulation formation. The cricothyroid membrane is closed, as are the soft tissues, above the laryngeal notch. The external perichondrium is reapproximated to close the remaining portion of the larynx. Again, the strap muscles are su-

38I

tured by reapproximatingtheposterior andanterior fascia in layers. A cuffed tracheostomy tube is inserted, and the final closure proceeds as in laryngofissurecordectomy. For the anterior-commissure procedure, after the tumour is removed, the possibility for a near-normalvoice exists because the majority of each true cord has been preserved. A Montgomery laryngeal keel is then placed between the thyroid cartilage remnants and secured into position with a Prolene suture (Fig. 52.12). The tissues above and below the keel are closed with interrupted chromicsutures to secure the closure of thethyroid cartilage. This is done by closing the cricothyroid membrane and soft tissues above the thyroid notch. By plating a blue Prolene suture to secure the keel in position, it can easily be found and removed at a later date. The keel is generally removed through a small incision, with the patient given local anaesthesia, at about 4 weeks postoperatively. A cuffed tracheostomy tube is placed, and the neck incision is closed, as described above. A neck dressing is applied postoperatively.

Postoperative management

Fig. 52.11 Reattachment o f contralateral true and false cords. (From Olsen, 1992. By permission of Mayo Foundation.)

Fig. 52.12 (a) Removal o f anterior pot-tion of vocal cords and overlying cartilage. (b) Insertion of laryngeal keel. (From llsen, 1992. By permission of Mayo Foundat:ion.)

The tracheostomy tube is kept inflated for the first 2448 h postoperatively. At that time, it can generally be changed to a small no. S metal tracheostomy tube and of usually corked. When the patient can tolerate corking the tracheostomy tube for 24 h, the tubeis removed, and thetracheostomy site is allowed to heal secondarily. Patients begin speech whenthetracheostomytube is

3 82

Chapter 52

occluded, and 'no limitations are given about the use of their voice in the postoperative period. Feeding by mouth can generally begin after the tracheostomy tube is removed. Patients will do best with a soft diet. In most cases, there are no problems with aspiration. The Penrose drain is generally removed the day after the operation. Broad-spectrum antibiotics are given preoperatively and forabout 5 days postoperatively. After vertical partial laryngectomy, patients generally breathe and eat normally. Stenosis and aspiration are rare. The single exception to no formal reconstruction is hemilaryngectomy. Because half of the thyroid ala and onearytenoidare removed, problemswith laryngeal incompetence, aspiration and poor voice are common sequelae. In these cases, theauthor uses a fascialmyotransposition graft with the strap muscles to reline and surface the missing hemilarynx. After hemilaryngectomy, problems of stenosis and retained tracheotomy tubes are generally related to a narrowed glottic lumen due to the reconstructive procedures.

eo Complicationsafter vertical partial laryngectomy are infrequent. An earlier report by Neel et al. (1980) described complicationsin 26% of a series of vertical partial operations. The operative and postoperative problems included atelectasis, pneumonia,subcutaneous emphysema, wound problems, removal of granulation tissue and poor ultimate voice. Granulation tissue will be found in the healing laryngeal bed in all patients if the larynx is observed early. This generally resolves within 3-6 months. Rarely, persistent granulation tissue must be removed because of interference withthe voice or airway. Problems with infection can occur, especially if the perichondrium is removed from the underlying cartilage in additionto the perichondrium being removed from the outer surface of the cartilage. Infection is more common after the treatment of radiation failure. Hospitalisation usually averages 5 days.

Summ~ Open laryngeal proceduresarea versatile and efficacious treatment option for treating the wide spectrum of

large T1 glottictumours.Thisoperation is especially applicable whentheanterior commissure area is involved. Vertical partial laryngectomy for select and appropriate T1 glottic tumours offers excellent curative results at the cost of alteration in vocal quality. Althoughthe voiceis altered, this operation ultimately gives the highest local control rate and disease-free survival and preserves the greatest number of laryngeal voices.

References Bailey BJ (1985) Glottic carcinoma. In: Bailey BJ & Biller HF (eds) Surgery of the Larynx. Philadelphia, W.B. Saunders, p. 267. Chiesa F, TradatiN, Costa L etal. (1991) CO, laser surgery in laryngeal cancers: three year results. Tumori 77, 151-4. Crissman JD, Zarbo RJ, Drozdowicz S, Jacobs J,Ahmad K & Weaver A (1988) Carcinoma in situ and microinvasive squamous Carcinoma of the laryngeal glottis. Arch. Otolaryngol. Head Neck Surg. 114, 299-307. DeSanto LW (1987) Surgical perspective. In: Thawley SE & Panje WR (eds) Comprehensive Managementof Head and Neck Tumors, Vol. 1. Philadelphia, W.B. Saunders, pp. 1029-39. DeSanto LW & Vaughan CW (1991) Early carcinoma of the larynx. In: Silver CE (ed.) Laryngeal Cancer. New York, Thieme Medical Publishers, pp. 151-61. Kirchner JA (1984) Pathways and pitfalls in partial laryngectomy. Ann. Otol. Rhinol. Laryngol. 93, 301-5. Kirchner JA (1989) What have whole organ sections contributed to the treatment of laryngeal cancer? Ann. Otol. Rhinol. Laryngol. 98, 661-7. Krespi YP & Meltzer CJ (1989) Laser surgery for vocal cord carcinoma involving theanterior commissure. Ann. Otol. Rhinol. Laryngol. 98, 105-9. Neel HB, 111, Devine KD & DeSanto LW (1980) Laryngofissure and cordectomy for early cordal carcinoma: outcome in 182 patients. Otolaryngol. Head Neck Surg. 88, 79-84. Olsen KD (1992) Laryngofissure-cordectomy and its variations. Instr. Courses 5, 307-12. Olsen KD & DeSanto LW (1990) Partial vertical laryngectomy-indications and surgical technique. Am. J.Otolaryngol. 1 1 ,152-60. Olsen KD, DeSanto LW & Pearson BW (1987) Positive Delphian lymph node: clinical significance in laryngeal cancer. Laryngoscope 97, 1033-7. Olsen KD, Thomas JV, DeSanto LW & Suman VJ (1993) Indications and results of cordectomy for early glottic carcinoma. Otolaryngol. Head Neck Surg. 108, 277-82. Ossoff RH, Sisson GA & Shapshay SM (1985) Endoscopic management of selected early vocal cord carcinoma. Ann. Otol. Rhinol. Laryngol. 94, 560-4. Schwartz AW, Hollinshead WH & Devine KD (1963) Laryngectomy: anatomy and technique. Surg. Clin. North Am. 43, 1063-79.

Conservation surgery of the larynx in the form of horizontal partiallaryngectomy (HPL) wasfirst described by Alonso in 1947. After a shaky beginning, the technique became more popular over the ensuing decades, mainly as a result of the work of Bocca et al. (1983) and Ogura et al. (1980) as well as histological studies by Kirchner and Carter (1987). Otherworkers followed, and gradually the indications for the procedure became more accepted and widened to include more extensive lesions. Although an examination of the barriers and compartments involved show that cancer may easily spread from the supraglottis (Tucker, 1961), in certain patients local excision of the supraglottic areaby HPL has been documented as being oncologically sound(Tucker,1961; Bocca et al., 1983).

Supraglottic cancer isdefined asa lesion affecting the area above the true vocal cords, and includes the roof and lateral walls of the sinus of Morgagni,the false vocal cords,the aryepiglottic folds and the laryngeal surface of the epiglottis. Invasion of the pre-epiglottic space, the base of the tongue and the prelaryngeal strap muscles, as well asthepharynx, may occur (Gregor, 1988).

that they invade the pre-epiglottic space. It should be possible to remove the tumour while sparing the entire glottis, including both arytenoids, the muscosa over the vocal cords and thelower half and superior cornuof the thyroid cartilage on the contralateral side. 2 The pre-epiglottic space can be removed by this operation; thus early invasion is not a contraindication. 3 Indications include any lesion that can be resected allowing a generous margin in all directions except the inferior margin, where experience has shown that margins of 3 or 4mm appear to be adequate. Contraindications are fixation of the vocal cord and extension to the arytenoid and postcricoid area. Relative contraindications are involvement of the pharynx and tongue unless these are very early and limited. Some authors advocate extended HPL for these lesions and lesions that involve an arytenoid. In the description that follows, only the classical horizontal partial laryngectomy, possibly including a small amount of tongue base or the medial wall of the pyriform fossa, will be described.

lie 1 Laryngeal carcinoma of an early stage that is situated above the plane of the ventricles may be suitable for this operation.This will include T1, T2and certain T3 lesions, which are classified as such by virtue of the fact

383

Neck dissection, either uni- or bilateral is often performed at the same time as HPL. The management of squamous-cell carcinoma(SCC) of thesupraglotticlarynx requires a different from philosophy glottic tumours. Because of the tissues involved and the natural areas of spread of supraglottic tumours, the lymphatic system is involved at a much earlier phase in thedisease and thusneck-nodal metastases are more common. Furthermore,thesupraglottis may be thought of asa midline embryological structure with lymphatic drainage to both sides of the neck. It is thought thatthis is the

384

Chupter 53

reasonwhybilateral neck metastases occur so frequently (Bocca et al., 1983). Thishas led to a longstandingcontroversyas tohow the neck should be managed in supraglottic disease (Gregor et al., 1996a). When looking at supraglottic cancer in general, some authors have found no improvement in the results of treatment over four decades (Zamora et al., 1993); others have found that bilateral elective neck dissection has improved the locoregional controland even survival (Lutz et al., 1990; Weber et al., 1994). Neck dissection can be included en bloc during HPL in thesame way as during total laryngectomy.

Preoperative management The preoperative work-up should include full ENT examination and direct examinationof the larynxto determine the spread of the tumour. CTscanning should also be obtailned to assess pre-epiglottic space invasion or framework invasion. Thepulmonaryfunction of the patient is importantand lungfunction tests and a pulmonologist’s opinionshould be obtained.This is more important than the chronological age of the patient. The presence of oesophageal reflux should be investigated by fluoroscopy. Acid reflux may negatively influence the healing and rehabilitation of these patients. If present, it may sway the balance against the procedure or suggest that aggressive anti-reflux management should be instituted. Perioperative antibiotics should be used for between 48 h and 5 days and should include Gram-positive and Gram-negative cover, as well as anaerobic agents.

Operative technique Thisprocedure seeks to remove theentire epiglottis, hyoid bone, pre-epiglottic space, false cords and upper half of the thyroid cartilage. The hyoid bone may be preserved in some cases and there is evidence that reconstruction and postoperative swallowing are facilitated by this (Gregor et al., 199613). The vocal cords and arytenoids are spared. Inclsion 1 An apron flap is used. A neck dissection can be encompassed in the same incision if it is extended laterally anduptothe mastoid.The flap is raised inthe subplatysmal plane. Tracheostomy is performed at any convenient stage of the procedure. 2 The hyoid bone, if it is to be preserved, is grasped and the muscles attaching below (sternohyoid, thyrohyoid

Fig. 53.1 Perichondrium incision.

and omohyoid) aresevered using the cautery knife. This is performed above the hyoid, cutting the suprahyoid musculature, if the hyoid is to be removed. The hyoid should be sacrificed if there is anydoubtaboutthe extent of the tumour or if the pre-epiglottic space is involved. 3 Next the strap muscles are incised at the upper margin of the thyroidcartilage. The greater cornuis exposed on the involved side. On the uninvolved side, the sternohyoid, omohyoid and greater cornu are preserved alongwiththesuperior laryngeal nerve and vessels. These are important for postoperative swallowing and laryngeal competence (Fig. 53.1 ). 4 The incision along the upper border of the thyroid cartilage is carried through the perichondrium and is extended to the cornu andlateral border on the involved side, where the inferior constrictor fibres are also severed (Fig. 53.2). 5 Next the perichondrium is elevated from the thyroid cartilage inferiorly to apoint below the level of the proposed cartilage incisions. This differs in males and females; the anteriorcommissure is situated between the upper and lower halves of theanterior ridge of the cartilage in males and is somewhat higher in the female larynx. Hence the cartilage incision is made higher in the female patient. If the thyroid cartilageis heavily ossified, the cut should be made using a micro-oscillating saw to avoid fracture.

Horizontal (Supraglottic) Laryngectomy

385

Fig. 53.2 Extension of incision.

Opening into the lumen

This must be done with care in orderthat the tumour is not approached too closely; entry should be performed either from the pyriformfossa or from thevallecula. The opening is gradually continued with the tumour under direct vision (Fig. 53.3). Good light and suctionare essential. After the upper excision has been completed, an incision is made on the lower margin, which passes through the lateral extent of the ventricle, preserving the Fig. 53.4 Supraglottic tumour excised with continuous traction.

mucosa over the vocal cords and passing through the petiole anteriorly. Posteriorly the aryepiglottic fold is incised over thearytenoid, leaving this area bare of mucosa (Fig. 53.4). The mucosa of the posterior commissure is left intact to avoid interarytenoid scarring (Fig. 53.5). Some surgeons advocate a cricopharyngeal myotomy to facilitate swallowing. This is undertaken by passing a finger into the cervical oesophagus and incising the cricopharyngeal fibres laterally with aknife. Others consider this unnecessary, butthe tonicity of thisarea should be tested with the finger and, if in doubt, it is probably better to perform the myotomy. Care must be taken, however, to preserve therecurrent laryngeal nerve, which enters the larynx behind the cricothyroid joint. The myotomy is therefore made as far posteriorly as possible. Repair Fig. 53.3 Internal laryngeal incision.

This is accomplished by suturingthe defect by deep, strong, absorbable material, approximating the remnant

386

Chapter 53 with swallowing (Gregor et al., 199610).Difficulty with the airway may occur, particularly when radiation is administered postoperatively, butre-tracheostomy is usually not required. These patients must be carefully observed and, if necessary, steroids and adrenaline nebulisation should be used to reduce oedema. The help of speech therapists is essential in the postoperative rehabilitation of swallowing and speech. Local recurrence in thelarynxcan be managed by completion laryngectomy. In this case primary vocal rehabilitationwith an indwelling voice prosthesis is recommended.

Fig. 53.5 Opening into the lumen.

of thyroid cartilage to the base of tongue if the hyoid was removed or around the hyoid if it was preserved. In the case of placing sutures in the tongue base, where the hyoid is removed, Ogura et al. (1980) have made the point thatit is not desirable to bring the mucosal edge of the tongue base to oppose the mucosa of the anterior commissure. This tends to bring the food bolus directly on tothe vocal cords. The sutures are therefore placed in the raw muscle edge of the tongue, thus resulting in an overlap or ‘shelf‘ above the glottis (Ogura et al., 1980). Inferiorly, thesuturesarecarriedthroughthe perichondrium and canalso be taken through drill holes in the thyroid cartilage. The sutures are all placed insitu before attempting to close the defect. To avoid tension, all sutures are held taut by the assistant while the surgeon knots them sequentially, thus approximating the tongue base (or hyoid) to the remnant of the thyroid cartilage. The strap muscles are then approximated in the midline and sutured to thetongue base or hyoid bone above. Suction drainage should be employed.

One of the major concerns after HPL is decannulation and aspirationwithdrinking. Usually decannulation can be achieved within 3 weeks after surgery, even when a bilateral neck dissection has been performed. Aspiration, however, remains a concern and even at 6-months up to 40% of patients may still experience difficulty

Because of the prevalence of lymph node metastases in supraglottic cancer, the regional spread of the disease must be aggressively managed. This includes bilateral neck dissection where indicated. Some authors (Weber et al., 1994) have suggested routine bilateral neck dissection in all cases. A more conservative approach with regard to the nodal status, together with postoperative radiation if indicated, appears more logical (Gregor et al., 1996a).

Alonso JM(1947) Conservative surgery of cancer of thelarynx. Trans. Am. Acad. Opththalmol. Otolaryngol. 51, 633-42. Bocca E, Pignataro 0 & Oldini C (1983) Supraglottic laryngectomy: 30 years of experience. Ann. Otol. Rhinol. Laryngol. 92, 14-18. Gregor RT (1988) The preepiglottic space revisited: is it significant? Am. J.Otolaryngol. 11, 161-4, Gregor RT, Oei SS, Hilgers FJM, Hart AAM, Balm AJM & Keus RB (1996a) Management of cervical metastases in supraglottic cancer. Ann. Otol. Rhinol. Laryngol, 10.5, 845-850. Gregor RT, Oei SS, Baris G, Keus RB,Balm AJM & Hilgers FJM (1996b) Supraglottic laryngectomy with neck dissection and postoperative radiation in themanagement of supraglottic laryngeal cancer. Am. J.Otolaryngol. 17, 316-321. Kirchner JA & Carter D (1987) Intralaryngeal barriers to the spread of cancer. Acta Otolaryngol. (Stockh.) 103, 503-13. Lutz CK, Johnson JT, Wagner RN & Myers EN (1990) Supraglottic carcinoma: patterns of recurrence. Laryngoscope 99, 12-17. Ogura JH, Marks JE & Freeman RB (1980) Results of conservation surgery for cancers of the supraglottis and pyriform sinus. Laryngoscope 90, 591-600. Tucker GA (1961) Histological method for the study of the spread of cancer within the larynx.Ann. Otol. Rhinol. Laryngol.70,910-21. Weber PC, Johnson JT & Myers EN (1994) The impact of bilateral neck dissection upon pattern of recurrence and survival in supraglottic carcinoma. Arch. Otolaryngol. 120, 70-6. Zamora RL, Harvey JE, Sessions DG & Spitznagel EL (1993) Clinical staging forprimary malignancies of thesupraglotticlarynx. Laryngoscope 103, 69-77.

ecto

a

ER F. PERRY

ica

Wide submucosal disease

S

Resections of thehypopharynxare principally performed to treat malignancy, chiefly squamous-cell carcinoma (SCC). However, it may rarely be indicated for massive benign disease or aspiration/stricture formation following majortrauma. Occasionally laryngeal cancers may spread posteriorly to envelop thehypopharynx, but anteroinferior extension is more common. In contrast, the larynx is a frequent pathway for spread of SCCs from the hypopharynx.The main indication for pharyngolaryngectomy is thereforea cancer arising from the hypopharynx. SCCs of the hypopharynx have a number of unusual features which predispose to a poor prognosis. es

Seventy per centof SCCs have palpable nodal disease on presentation. Of those with clinically negative necks, a further 60% are estimated to have microscopic nodal involvement on presentation. Tumours of the hypopharynxoften present with large nodaldeposits from very small, ‘silent’, primary lesions.

This is a particular problem withlesions of the posterior hypopharyngeal wall. It is not uncommon for a lesion 1cm across to have more than 3 cm submucosal spread in every direction. Cancers in the lower hypopharynx and upper oesophagus tend to spread inferiorly. Hence a minimum of 5 cm caudal clearance is required when resecting lesions in the upper oesophagus, while a 2cm margin is needed for piriform fossa lesions. With rare, small, posterior-wall lesions, biopsies of the mucosa 1 , 2 and 3cm from the margins of macroscopic disease in superior, inferior and lateral directions accurately size the lesion and its submucosal spread, in order to plan theappropriate surgical approach. Not every patient requires total a pharyngolaryngectomy for hypopharyngeal cancers. Sometimes laryngeal-sparing procedures are appropriate, provided there is 2cm clearance of macroscopic disease in all directions. Relative radio resistance

Almost allstudieslooking at surgery versus radiotherapy show improved survival with surgical excision (Eisback & Krause, 1977; Persky & Daly, 1981; El Badawi et al., 1982).Most centres use combinedmodality therapy of surgery with pre- or postoperative radiotherapy. A number of institutions have questioned whether postoperative radiotherapy adds any extra survival to that of the adequate excision, especially bearing in mind the high incidence of second primary lesions that may be more radiosensitive. For very small lesions, where laryngeal conservation surgery may be safely performed,the author prefers surgery withpostoperativeradiotherapy to cover the

The superior hypopharynx is capacious, so that lesions may grow to be very large before producing symptoms. Presenting symptoms are commonly odynophagia due to ulceration,obstructive dysphagia from bulky tumours, hoarseness due to laryngeal involvement or a lump in the neck from nodal metastases or direct tumour spread.

387

3 88

Chapter 54

primary’s propensityforsubmucosal and lymphatic spread and microscopic lymph node involvement. When thelarynxcannot be saved, surgery withpostoperative radiotherapy is offered. Sometimes a small anterosuperior hypopharyngeal lesion may be adequately encompassed by a slightly extended laryngectomy; however, the results of pharyngolaryngectomy with jejunal interposition in the author’s institution are excellent, making this the treatment of choice for the larger lesion (Smith et al., 1992). Some authors(Harrison,1970,1981;Harrison & Thompson,1986) point to the tendency of hypopharyngeal cancer to spread submucosally and to form ‘skip lesions’ further down the oesophagus.They therefore feel that adequate clearance can only be obtained by full pharyngolaryngo-oesophagectomy if the tumour is low in the hypopharynx. However, recurrence in the oesophagus has not proved to be problem a with jejunal interposition(Gluckman et al., 1987). author’s The institution prefers to reserve pharyngolaryngo-oesophagectomy for patients with elongated oesophageal lesions. The results (Smith et al., 1992) justify the assertion that the ‘gold-standard’ approach to most cases of hypopharyngeal SCC is pharyngolaryngectomy with jejunal interposition, which is the operation described in detail below. However, partial hypopharyngectomy, partial laryngectomy, extended laryngectomy and pharyngolaryngooesophagectomy all have their places in themanagement of these tumours. r”

Full assessment of the extent of the involvement of the larynx and hypopharynx is made under general anaesthetic, and the areas of involvement are drawn accurately at the time of the original biopsy. Palpation of neck nodes while thepatient is anaesthetised and relaxed is performed, remembering that ‘midneck nodes’ may represent direct tumour extension. A full panendoscopy is then performed to exclude a synchronous second primary, paying special attention to the oesophagus. A CT scan of the neck and uppermediastinum is performed in order to assess tumour spread within the larynx and hypopharynx and to look for direct spread (T4)into theneck tissues. CT assists in the assessment of nodal spread. Lower hypopharyngeal lesions spread via paratracheal nodes to the mediastinum; hence low tumours necessitate a mediastinal dissection. However, frank CTinvolvement of mediastinal structures is generally regarded as a contraindication to surgery. Upper

oesophageal lesions spread to the hilum of the lung, the coeliac nodes and the liver; thus the upper abdomen and liver arealso assessed by CT scan before surgery in patients with lowlesions of the hypopharynx and upper oesophagus. Aclotting screen and liver-function tests are performed and 4 units (2L) of blood is cross-matched. (A pharyngolaryngectomy may lose 500ml of blood, as maythefrequently needed radical neck dissection.) Mostpatients donot need atransfusionduringthe procedure; however, the patient needs to have a haemoglobin of at least logldl postoperativelyforoptimal healing to occur. The author generally invites a dietitian to consult the patient. The patient is given a high-calorie/protein dietary supplement with the addition of vitamin B complex, vitamin C and folic acid 20 mglday. At least 2 days preoperatively, 20mg of vitamin K and 5000 units of vitamin B,, are given parenterally. The extra demandsof healing in somebody with real or potential deficiencies are covered safely and cheaply by this regimen. Lastly, before the surgical reconstruction is decided upon,any previous abdominal surgical history is assessed by the involved general surgeon to decide suitability for jejunal conduit resection. Previous extensive upper abdominal surgery or peritonitis may make harvesting difficult.

Relevant anatomy Thehypopharynx is divided into subsites and staged according to the combined UICC/AJCC 1987 classification (Fig. 54.1). It runs from the level of the hyoid bone/ pharyngoepiglottic fold to theupperborder of the cricopharyngeus. The pyriform fossa is shaped like an inverted pyramidal cone, with its ill-defined apex at the level of the upper border of the cricoid. The postcricoid area is a complete ring of foregut tissue corresponding to the levels of the cricoid cartilagesuperiorly and inferiorly. The posterior wall runs from the arbitrary level of the hyoid bone to theupperborder of the cricoid. The marginal area between hypopharynx and larynx is oncologically included in the hypopharynx, as tumours in thisarea have thelatepresentation,bad prognosis and tendency towardscaudalextension of hypopharyngeal lesions. Hypopharyngeal cancers do invade the larynx and frequently fix the vocal cord by invasion of the cricoarytenoid joint and the recurrent laryngeal nerve and by direct extension into the paraglottic space lying unprotected medially (Figs 54.2 and 54.3).

Pharyngola~yngectomyandPharyngolaryngo-oesophagectomy 3 89 placed vertically) and a head ring stabilises the patient’s head and neck. Povidone-iodine preparation (or alcoholic chlorhexidine if iodine-sensitive) is applied from mouthto pubis. The body is drapedto expose the prepared areas. Incision (Fig. 54.4)

In an average to long neck (Fig. 54.4a), ahorizontal incision with a lateral ‘T’ is performed if there is to be a radical neck dissection. The vertical incision is thrown intoa lazy ‘S’ to minimise webbing. A 3.5 x 3.5cm stomal hole is made which is slightly bigger than the trachea, in order to pull the stoma open with healing/ scar retraction. A patient with short a thick neck is usually approached using a Gluck-Sorensen incision (Fig. 54. 4b). This U-shaped incision is not extended too far cephalad (otherwise the inferior portion of the flap may slough) and is made broad-based. A lateral ‘T’ running at right angles from this extended ‘U’ on one side can allow access for a radicalneck dissection. The lateral ‘T’

Fig. 54.1 Subsites.

Operative technique Preparation

1 Thisoperation is always performedunder general anaesthetic (CA). Occasionally, awakebronchoscopeguided intubations are necessary for safe induction of anaesthesia. 2 Prophylactic antibiotic cover forpotentialaerobic/ B is commenced. Theauthorcuranaerobicpathogens rently uses ticarcillin/clavulanic acid 3 g, three times a day for 3 days. Antibiotics cease after 3 days provided the patient is afebrile and hidher chest is clear on X-ray and auscultation. 3 The patient is positioned supine on a warming mattress with the sandbag horizontally beneath the shouldersforextension (the patienttends to roll off one

rent laryngeal

Fig. 54.2 Piriform fossa lesions readily invade cricoarytenoid joints, recurrent laryngeal nerve and paraglottic space.

Fig. 54.3 Lymphatic drainage of hypopharynx.

Right angled junction2cm behind carotid

~

artery

Lateral ‘T’ at right angles positioned behind carotid

Apron extension of Gluck-Sorensen incision

J

Fig. 54.4 Potential incisions.

must always be positioned behind thecarotidartery in incision (Fig. 5 4 . 4 ~ ) t oallow access intotheposterior case there is breakdown of the ‘T’ junction tips. Another inferior neck area in order to remove the contents of the way of doingaradical neck dissection is toputan posterior triangle of the neck withoutalateral ‘T’. ‘apron extension’ onthe side of the Gluck-Sorensen

~baryngolaryngeGtomyand Pharyn~olaryngo-oesopbageGtomy 331 Procedure in stages

1 The skin incision is marked and points are tattooed with methylene blue for ease of closure. 2 Injection of vasoconstrictor. The author uses 20ml of a solution of 1m1of l :1000 adrenaline in 100m1 saline (1in 100 000 adrenaline), or half this concentration (0.5m1 adrenaline in 1OOml saline) if a long incision (e.g. with radical neck dissection) is required. (This solution has apH of 7, compared with apH of 4.8 when xylocaine with adrenaline solution is used, and adrenaline is more vasoactive at a pH of 7.) 3 The incision is carried through the platysma, and flaps are raised in a subplatysmal plane to expose to the suprasternal notch inferiorly and 2cm over the sternomastoids laterally. Superiorly the flap is raised to be 2cm above the hyoid bone. The flaps are obviously taken wider on the side of radical neck dissection if needed. Silk stay sutures hold open the flaps. 4 The larynx and hypopharynx are mobilised laterally from the carotid sheath structures. The superior layngeal neurovascular bundle is isolated at the distal end of thegreatercornu of the hyoid bone. Major arteries and veins are tied individually, but smaller vessels are tied off in groups for speed. The middle thyroid veins are ligated. Theposterior wall of thepharynx is separatedfromthepre-vertebral fascia by blunt dissection. 5 The strap muscles are divided low in the neck and the thyroid isthmusis divided. If the lesion is high in the hypopharynx, both lobes of the thyroid should be separated from the trachea,using coagulating diathermy for speed when dividing through the multiple small vessels running between the thyroid gland and trachealcricoid. The inferior thyroid artery's supply to the parathyroid glands is preserved if possible. (There is a high incidence of later hypothyroidism in irradiated patients who have had one lobe of the thyroid surgically removed.) For lower pyriform fossa and posterior-wall tumours and all postcricoid lesions, thethyroidgland and parathyroids on the side of involvement are resected, and often both sides are taken. If the patient required a tracheostomy due to airway obstruction in a prior procedure, thethyroidgland is routinely Completely removed along with the tracheostomy tractand overlying skin. When the thyroid gland is completely removed and theparathyroids have not been preserved, thenthe parathyroidsshould be identified fromthe specimen, sliced into thin sections and reimplanted into the preserved sternomastoid or a similar muscle. The parathyroid glands are pale brown and are situated in the inferior half of the posterior margin of the thyroid.

Unlike fat lobules, they bruise to a purple-brown colour withhandling, and sink whendroppedintonormal saline. When in doubt, especially if there is a possibility of the nodular tissue being an enlarged lymph node, a slice of the nodule is sent for frozen section to confirm that it is parathyroid tissue before reimplanting. 6 The trachea is entered at a sufficient level to encompass the malignancy but not so low as to compromise attachment of the stoma to the skin of the suprasternal notch. Usually thetrachea is entered by ahorizontal incision, extended to encompass 40% of the tracheal circumference, and an armouredendotrachael tube (ET) is inserted to replace the original oroendotracheal tube, which is removed Completely from the patient by the anaesthetist. The cuff of the new tube is inflated just enough to keep blood out of the airway-too high a pressure will damage the mucosa and will commonly cause the tube toslip up or down continually and get in the way of the surgeon. A silk suture with a tie-around secures the tube to the chest skin at the right level to maintain equal lung ventilation. Stay sutures of nonbraided material are placed in the walls of the trachea and oesophagus below theintended inferior excision line tostop these structures being later 'lost' in the mediastinum. Usually stay sutures are 210 chromic catgut on a tapered needle, with the needle left on to be later used as deep anchoring sutures from the tracheal wall to the undersurface of the stomal skin flaps. 7 The hyoid bone is grasped with an Allis forceps, as is done when performing a total laryngectomy (Fig. 54.5). The geniohyoid and genioglossus muscles are separated from the body of the hyoid bone, and the middle constrictor and hyoglossus are separated from the greater cornu, using pencil diathermy on a low cutting and, as required, low coagulation setting. Scissors are used to free the medial attachments of the greater cornua. Care must be taken to stay close to the lesser cornua when separating tongue muscles- the hypoglossal nerves can be less than 1cm above them, lying on the hyoglossus, and may be damaged when freeing the hyoid bone. 8 The hyoepiglottic sheet ligament is followed by the diathermy needle into the vallecula on the opposite side to the cancer. The mucosa is entered and the cut is taken through the affected side with an adequate 2cm margin superiorly. The posterior surface of the pharynx should have been previously separated off thepre-vertebral fascia by blunt dissection, and thesuperior incision is continued with scissors to include the posterior wall in line withthe hyoid bone, or above if there is oropharyngeal spread. 9 The inferior tracheal incision isbevelled upwards to leave an obliquesuperior end to thetrachea.The

Fig. 54.5 Superior and lateral mobilisation of the larynx and hypopharynx.

posterior tracheal wall and trachealis muscle are separated for 1.5cm from the anterior oesophageal wall. 10 The oesophagus is divided at the appropriate level below the cricopharyngeus. At least a 2cm margin is required for pyriform fossa lesions, with up to 5cmfor cricopharyngealhpper oesophageal tumours. 11 In patients where ahorizontalskin incision with separate stoma is done, the tracheal stump is sutured into the skin stoma (Fig. 54.6). Any tension should be carried by three to five deep 2/0 chromic catgut stay sutures, now used to anchor the trachea up under the stomal skin flaps. The skin-mucosa suturesare of a vertical mattress type, which donot go through tracheal mucosa except posteriorly, where the tracheal cartilage rings are deficient. The sutures should be 68mm apart.Theauthor uses a4/0 blue dissolving monofilament (Maxon orPIX) suture ona small cutting needle. Mucosa and skin should appose with a loose overlap. 12 If primary voice restoration is to be done, a fistula tract from the back wall of the trachea to the oesophagus is made and a size 14 catheter inserted (Fig. 54.7). This catheter’s passage through common the tracheal/oesophageal wall should be hidden in fibromuscular tissue. Thelength of the pharyngealoesophageal defect is then measured accurately. The defect is usually between 6 and 8 cm when thetissues are slightly on the stretch. 13 At this point the otolaryngologist takes lunch and afternon tea while theabdominaland microvascular

-~

Fig. 54.6 Securing the stoma.

Fig. 54.7 A primary voice puncture may be fashioned between the stoma and the butt of the oesophagus. The catheter should not be visible from inside the wound. Close over it with sutured tissue if necessary.

surgeons do their best! The abdominal surgeon should be aware that the removal of the larynx prevents adequate coughing andthat the patient’s coughing attempts postoperatively will put greater strain on hidher abdominal suture line than is usual. Jejunum is harvested with the longest, straightest vas-

Pbary~~ol~rynge~tomy and ,Pbaryngolaryngo-oesophagectomy

39 3

Fig. 54.9 Jejunum segment sutured in under slight tension. Fig. 54.8 Jejunum segment with long vascular arcades.

cular arcade possible (Fig. 54.8). The proposed transplant segment is accurately measured (also whenslightly on the stretch}and thendivided off, but left to lie warm, moist and closeted withintheabdomenuntilthe microvascular surgeon hasisolated and prepared hidher intended neck vessels. The enteric vessels are left attached to this isolated segment of jejunum and an endto-end anastomosis rejoins the intestine’s continuity. The vessels commonly used by the microvascular surgeon are the superior thyroid, inferior thyroid and transverse cervical vessels, depending on the size match and availability. The veins available can include an end-toside anastomosis to the internal jugular vein (IJV) or end-to-endanastomosiswiththeexternal jugular or transverse cervical vessels. As the IJVis a high-flow vessel, the suction effect produced by the more rapid passage of blood theoretically draws venous blood from thetransplanted vein more effectively, lessening the chance of it obstructing. It is best not to use anterior jugular veins (AJVs), as they usually have low flow rates. The jejunum is inserted into the neck, with its caudal end placed inferiorly and cephalic end superiorly; that is, be sure it is not antiperistaltic (Fig. 54.9). Peristalsis often continues to occur in the transplanted bowel. As the small bowel’s contractions occur slowly (three per minute), peristalsis has little part to play in the rapid

transit of food during the second stage of swallowing. However, if the jejunum is placed in an antiperistaltic direction, the patientmay experience a feeling of MUCUS welling up into the throat. Serosa protectsthetransplanted jejunum from taking up the surrounding blood supply, so that division of the transplanted bowel’s feeding artery and vein, even if years later, may result in late sloughing of the graft-a problem not encountered in myocutaneous transfer. The abdominal surgeon then anastomoses the transplanted and newly revascularised jejunum, being careful not to pull apart the microvascular anastomosis. Closure/drainage/dressings

A large-bore nasogastric tubeis inserted, even if there is aprimary voice-puncture catheterin place, as this is required in the postlaparotomy patient. Two3 mm suction drains areinserted, but they are kept away from the transplant’s vascular arcade. A 6mm suction drain is placed inferoposteriorly if a radical neck dissection was performed, and the neck is closed in two layers. The deep layer of dissolving sutures (usually 310 chromic catgut)holdsthe flaps together and is theimportant layer of closure. The skin’s layer of closure is for accuracy of apposition and tokeep the wounds airtight. The author uses running continuous 4/0 nylon for the skin, with interrupted sutures in any T-junctions. Interrupted

394

Chapter S4

skin closure is best for the whole length of the incisions if there has been preoperative radiotherapy. No dressings are placed over the wounds. An antibiotic-impregnatedointment is smeared over the wound to keep bacteria out, to stop a crust of blood from forming over the wound and to keep the nursing staff contented. A cuffed tracheostomytube is introduced and the flanges sutured in place to the skin (tape ties around the neck may compromise the microvascular arcade).

Postoperative management The tracheostomy tube’s cuff is kept inflated until the patient is. fully awake and is not oozing. It can then be changed for an uncuffed or laryngectomy tube.The tracheal stoma requires normal tracheostomy care, humidification and suction. The nasogastric tubeis left on free drainage and the patient is kept nil by mouth until bowel sounds start and flatus is passed, usually about the third day. Dextrose 500ml is run into the nasogastric tube over 4 h, which is then blocked off to see if the patient becomes nauseated. If it is well tolerated, half-stre~gth and then full-strength total liquid replacement diet (e.g. Isocal, Ensure, Osmolyte) is instituted. If there is no sign of pharyngocutaneous fistula, the patient starts a liquid and then solid diet after l 0 days, provided a barium swallow shows no leaks at the anastomoses. The patient’s free jejunal segment is inspected hourly for the first 12 h after surgery and then every 2 h for a further 36 h, every 4 h for2 days and thentwice daily for 4 days. Any change in thecolour of the jejunum is reported to the microvascular surgeon immediately and he/she inspects it. The haemoglobin must be keptabove10g/dl.The blood pressure should be kept above 100 mmHgsystolic from the start of the microvascular transfer to keep the free flap perfused. The free calcium/phosphate levels are estimated soon after surgery and 8 and 16h later,especially if both sides of the thyroid are removed. The author does not give calcium gluconate supplements unless the free calcium level (corrected for albumin)falls below 1.7Oiu. There is often a small transient fall in calcium and too early an introduction of supplements may suppress the patient’s own ability to adjusthidher calcium. Thyroxine replacement needs to be started within a coupleof weeks of total thyroid removal.

Complications Complications specific to this procedure include the following: 1 Loss of jejunal segment-replace with another segment. 2 Pharyngocutaneous fistula -maintainnasogastric alimentation. 3 Paralytic ileus-parenteral alimentation may need to be instituted if bowel sounds are delayed. 4 DuodenaUbiliary injury-use only an experienced abdominal surgeon. These patients rarely survive major abdominal complications. 5 Wound haematoma-the placement of suction drains may be compromised by the need to keep the drains away from the microvascular arcade. If a haematoma needs evacuation, be aware of the position of the vascular anastomoses and stay away from it if possible. Be sure themicrovascular surgeon is aware of what you are doing and is available to come in quickly if the vessels or their anastomoses are damaged.

Alternative procedures Extended total laryngectomies are the frequently used treatment of marginal and mid to high piriform fossa lesions in many institutions (Fig. 54.10). Indeed in the author’s own institution, a localised marginal or medi-

Fig. 54.10 Extended laryngectomy.

P b a ~ y n ~ ~ l ~ ~ ~ n and g e c Pba~y~golary~go-oeso~bagectomy tomy 39 5 ally placed piriform fossa lesion is frequently treated with this procedure. If the tumour is more laterally or posteriorly placed within the pharynx, a2cm margin of excision may leave only a thin bridge of the residual pharyngeal mucosa. It may then need to be closed tightly around nasogastric a tube or a pedicled myocutaneous flap must be swung into close the defect. Stricture formation is common if these manoeuvres are employed. It is the author’s contention that extended laryngectomy is only indicated forthe high anterior piriform fossa lesions (morethan3 cm abovethe cricopharyngeus)withoutposterior-wallextension of the incision when an adequate margin is obtained. The submucosal spread of 2cm that these lesions frequently exhibit is best encompassed by the radical removal allowablewith free jejunal replacement. Theauthor’s insititution has an operative mortality of 2% for this procedure, compared with 8-15% for total pharyngolaryngo-oesophagectomy withstomach pullup (Smith et al., 1992). When skilled microvascular surgery is unavailable, the author prefers pharyngolaryngo-oesophagectomy withgastricpull-upfortumoursapproaching closer than 3cm from the cricopharyngeus and for the more circumferential high lesions. Pha~ngo~aryngo-oesophagectomy The otolaryngologist’s role in totalpharyngolaryngooesophagectomy (TPLO) with stomach pull-up is little different to hidher role in pharyngolaryngectomy with jejunal conduit except for a few points. 1 The stomach is mobilised on the tenuous blood supply of the right gastroepiploic artery. Trying to stretch thestomachabovethe hyoid bone level places great tension on the anastomosis line. This operation is most suitable for lower lesions. 2 The abdominal/thoracic surgeon involved must choose between a two-stage (abdomenand neck) or three-stage (abdomen, neck and chest) procedure. Most authors suggest that thetwo-stageprocedure is best. However, the best results the author has seen for this operation were procedures performed by a ‘three-stage’ thoracic surgeon. 3 The stomach requires drainage a procedure (pyloromyotomy or pyloroplasty), as the operation cuts the vagal nerves. 4 The otolaryngology (neck) procedure is the same as for total pharyngolaryngectomy except that the hypopharynx must not be separated from the oesophagus. Rather,theotolaryngologist helps to bring the stomach upto the neck by bluntly dissecting the anterior

and posterior surfaces of the oesophagus at the appropriate time, to allow full mobilisation. The vascular supply of the oesophagus comes in laterally, and these vessels are best left alone until the actualelevation of the stomach to the neck. 5 A primary voice puncture is not usually successful, due to the capaciousness of the stomach. 6 The stomach may be slower to start working again, compared with the small intestine. Gastric stasis may occur despite bowel sounds being present. 7 Special problems of acid reflux into the mouth and ‘dumping’ may be sequelae of this form of surgery.

Suggestions for further reading For a description of partial hypopharyngectomy with laryngeal sparing, see Hawley and Pane (198’7). McNeil (1981) detailed five patientstreated by larynx-sparing procedures with a high rate of relapse and problems with aspiration. The authorhas a current series of 12 such patients, allalive and disease-free for at least 3 years, except for one patientwho presented at 62 monthswithasolitarycerebral metastasis, still with locoregional control.Only very small tumours,with multiple biopsy-proved lack of appreciable submucosal spread, are suitable for laryngeal-sparing procedures.

References Eisback KJ & Krause CJ (1977) Carcinoma of the pyriform sinus: comparison a of treatment modalities. Laryngoscope 87, 1904-9. El Badawi SA et al. (1982) Squamous cell carcinoma of the pyriform sinus. Laryngoscope 92, 357-64, Gluckman Jet al. (1987) Partial vs. total oesophagetomy foradvanced carcinoma of the hypopharynx. Arch. Otol. Head Neck Surg. 113 (l),69-72. Harrison DFN (1970)Pathology of hypopharyngeal cancer in relation to surgical management. J.Laryngol. Otol. 84, 349-67, Harrison DFN (1981)Surgical repair of hypopharyngeal and cervical oesophageal cancer. Ann. Otol. 90, 372. Harrison DFN & Thompson A (1986) Pharyngolaryngooesophagectorny with pharyngogastric anastomosis for cancer of the hypopharynx: review of 101 operations. Head Neck Surg. 8 (6),417-28. Hawley SE & Pane W (1987) Comprehensive Management of Head and Neck Tumours. Philadelphia, W.B. Saunders, pp. 783-93. Hermanek P & Sobin LH (1987) TNM Classification of Malignant Tumours (4th edn). Berlin, Springer-Verlag. McNeil R (1981)Surgical management of carcinoma of the posterior pharyngeal wall. Head Neck Surg. 3, 389. Persky M & Daly J (1981) Combined therapy vs. curative radiation in the treatment of pyriform sinus carcinoma. Otol. Head Neck Surg. 89, 87-91. Smith IM etal. (1992) Triple therapy for advanced squamous cell cancer of the head and neck. Aust. NZ J.Surg. 373-81.

Surgical Voice Restor NIGEL R. BLEACH AND ANDREW J.G. BATCH

Secondary Since tracheo-oesophageal puncture (TEP) was first described by Blom and Singer in 1980, it has become the most widely used technique for surgical voice restoration (SVR). It may be performed either at the time of laryngectomy (primary) or in patients who have previously undergone laryngectomy without voice restoration (secondary). There are two main categories of prosthetic devices, which actas valves withinthe surgical fistula. Nonindwelling prostheses are smaller and can be removed, cleaned and replaced by the patient at varying intervals asrequired (e.g.Blom-Singer prosthesis). Indwelling prostheses are larger and more robust, and stay in situ until device failure requires replacement by the surgeon (e.g. Provox). Thischapter describes the surgical techniques and principles involved in both primary and secondary SVR. Specific details relevant toboth Blom-Singer and Provox prostheses are included.

1 Patients who have failed to achieve satisfactory oesophageal speech after laryngectomy, despite adequate speech therapy. 2 Patients who have very poor-quality speech, or no voice, following more extensive resections (pharyngolaryngectomy and myocutaneous flap repair, or laryngopharyngo-oesophagectomy(LPO) with gastric transposition or free jejunum reconstruction). 3 Patients who find electrolarynx speech unacceptable (robotic quality, slow rate, poor intelligibility) or standard oesophageal speech inadequate (low volume, short phrases, staccato delivery) for daily communication. 4 Patients with good oesophageal speech who require excellent communication skills and fluent clear speech, e.g. teachers, broadcasters, clergy, etc.

indications

2 Patientswitha

Primary

Patients undergoing laryngectomy, including those requiring partial pharyngectomy with flap reconstruction, or total pharyngeal replacement with free jejunum or gastric transposition, may be considered for synchronous TEP and subsequent fitting of an indwelling voice prosthesis. This allows the patientto leave hospital with a functional voice, but does preclude careful assessment for SVR, and this may subsequently reduce the overall success rate. Emotional and social factors may prove to be particularly adverse, leading to late failures.

Contraindications Primary 3. There are no absolute contraindications to SVR.

T3 or T4 obstructing laryngeal tumour, extensive subglotticextension or peritracheal nodal involvement are athigh risk of stomal recurrence, and a primary TEP should probably be avoided. 3 Patients who require full-dose radiotherapy (RT)(5070Gy preoperative or plannedpostoperative)are at greater risk of fistula formation and woundbreakdown. In general, however, the presence of a well-constructed surgical fistula stented by a nasogastric tube should not interfere with woundhealing. If wound breakdown and/ or salivary fistula occurs, then stoma-gastric feeding via the tracheo-oesophageal (TE) fistula tube is well tolerated by the patient. Insertion of a prosthesis should be

SurgicalVoiceRestoration delayed until wound healing is achieved, or electively deferred in any patient at high risk of delayed healing. 4 Postoperative RT in a patient with a primary TEP may cause considerable peristomal reaction (tenderness, oedema, serous ooze and crusting),This makes accurate sizing and fitting of a Blom-Singer prosthesis difficult, and stomal occlusion for voicing becomes painful. Temporary stentingof the fistula with a catheterand delayed fitting of the prosthesis after completion of RT (or secondary SVR) may therefore be preferable. An indwelling Provox prosthesis fitted primarily should not need changing during RT, but voicing may not be possible initially, due to local reaction as above. Secondary and general

Most patients are ableto gain benefit from SVR using a voice prosthesis. Contraindications are relative, rather than absolute, and vary in significance and relevance in different patients.Factors to consider include the following: 1 drug abuse/alcoholism; 2 extreme age, frailty, senile dementia; 3 impaired eyesight, e.g. cataract, glaucoma, myopia; 4 impaired dexterity or incoordination, e.g. severe arthritis, Parkinson’s disease, CVA, etc; 5 coexistent chest disease with chronic cough,excessive sputum, dyspnoea at rest; 6 poor support from spouse, family, other relatives. A combination of two or three of the above adverse factors may, in practice, make succesful SVR impossible. However, with a given patient, trial and error are often required before a final decision to abandon TE fistula speech is made.Manualdexterityand visual acuity are more relevant to patients required to change non-indwelling prostheses, forwhomapermanently indwelling valve may be more appropriate.

Preoperative management Patient counselling

Full discussion withtheoperatingsurgeon, speech therapist, ENT nursing staff and successfully rehabilitated patients (both oesophageal and prosthetic speakers) is importantto allow informed decisionmaking. This may include the use of instructional videos, booklets, etc. and alsofamiliarisationwith equipment, e.g. voice prostheses, stoma valves, electrolarynxes.

3 97

Primary tracheo-oesophageal puncture

Full preoperative investigations prior to major surgery (as standard for laryngectomy/laryngopharyngectomy-see Chapters 51 and 54), plus endoscopic and radiological staging of the primary tumour, assessment of neck-node involvement and exclusion of distant metastases, are required. Secondary tracheo=oesophageal

1 Define the reason for failure of oesophageal speech, using acombination of radiology (preferably videofluoroscopy) and air-insufflation testing via a transnasal catheter to simulate phonation. This allows identification of patients with pharyngeal strictures or hypertoniclspastic pharyngeal function who fail to produce oesophageal speech oradequate voice on air insufflation. These patients usually require pharyngeal myotomy to allowgood voice production following TEP (Cheesman et al., 1986; Baugh et al., 1987; McIvor et al., 1990). 2 Patients who fail insufflation testing preoperatively, or whofail to produce fluent speech with a low-pressure prosthesis, may be retested after pharyngeal-plexus blockade, using local anaesthetic (LA) infiltration. Marcaine (10%) is injected intotheparapharyngeal region bilaterally while palpating (and hence protecting) thecarotid vessels. The needle passes medial to the fingertips and straight back onto thepre-vertebral fascia. After 10-20min, insufflation testing is repeated withthepharyngealconstrictorstemporarily relaxed, simulating myotomy. A good voice suggests that division of constricting pharyngo-oesophageal (PE)muscles is liable to be effective. 3 The neck and stomashould be assessed. A deeply recessed stoma prevents adequate stoma occlusion for voicing; this is readily corrected by dividing prominent sternomastoidtendons, which often ‘bow-string’ on either side of the stoma. A very small stoma may require stomaplasty to allow adequate space for the voice prosthesis. Excision of an overhanging crescentic lip of cartilage and fibrous tissue, together with a midline inferior or superior cartilage splitting incision and V-Y advancement flap is effective, as are bilateral Z-plasties. Either procedure is conveniently performed at the time of TEP and myotomy.

398

Chapter 55

As for laryngectomy (see Chapter 51). (Fig. 55.1) Followinglaryngectomy, RT andneckdissection,or flap repair o f the pharynx, the anatomy o f the neck is altered. 1 The pharynx lies immediately subcutaneously in the midline above the tracheostome. 2 The common carotid artery (CCA) and internal jugumay be densely adherent to the side of the lar vein (IJV) pharynx, and the carotid may also be subcutaneous on the side o f a previous neck dissection. 3 Normal tissue planes are distorted or obliterated by fibrosis, and landmarks are few. The pharynx may be more readily identified if distended by a large-bore (32FG) gastrictube,which gives afirm, palpablelandmark in the midline. The pulsatile common carotid laterally and the plane of thepre-vertebralfascia posteromedially areother valuable landmarks in the previously operated neck. Careful sharp dissection and blunt finger dissection to open tissue planes must be used in combination.

Fig. 55.2 Primary tracheo-oesophageal puncture.

cture

Pre~aratio~

The procedure is performed undergeneral anaesthetic (GA)asan integral part o f laryngectomy,andwith appropriateantibioticprophylaxis.TheTEP is performed following resection of the larynx, but prior to the closure o f the pharynx. Procedure

1

1

tendons lateral to stoma

I I

/

reopened on left side of neck]

f

,

---__ or buried in fascia

. .

.. . . .

. . . . . .

.~" "

Fig. 55.1 Secondary voice restoration-anatomy of myotomy approach.

1 Duringmobilisation o f the larynx,theconstrictor muscles should becarefullydissected and preserved, withoutcompromisingtumourclearance, to allow an adequate PE segment to be constructed. 2 Thepartywall between the tracheaand upper oesophagus should not be dissected below the level at whichthetrachea is resected to deliver the resected larynx.However,ifthetracheaandoesophagusare widely separated, then the party wall is reinforced with abuttresssuture (310 Vicrylmattress) to stabilise the region and prevent an area o f dehiscence and potential abscess formation (Hamaker et al., 1985). 3 A large, curved, artery forceps is passed into the lumen of the upper oesophagus and angled so that the tips

I

Surgical Voice Restoration

3 99

Fig. 55.3 Primary tracheo-oesophageal puncture-Provox technique.

indenttheposteriortracheal mucosa inthe midline, approximately 1cm inferior to the cut margin of the trachea. A S--lOmm transverse incision is then made on to the tips of the forceps (a vertical incision may disrupt the posterior tracheal wall) (Fig. 55.2). 4 A 14FG Ryle’s tube is introduced into the open tips of theforcep anddrawnthrough the incision into thepharynx. Thetube is then reversed and passed inferiorly, using non-toothed forceps and digital pressure, to be used postoperatively as a feeding tube. 5 For inserting the Provox prosthesis, a specially designed trochar and cannula, plus pharyngeal protector, are available. The latter is a short bevelled tube which is inserted into the upper oesophagus down to the level of the stoma. The sharp, pointed trochar and cannula are then used to puncture the party wall 1cm below the transected tracheal margin (Fig. 55.3). 6 In a routine laryngectomy, without preoperative irradiationor flap reconstruction,theProvox prosthesis

may be inserted at the time of surgery, as first described by Hilgers and Schouwenburg (1990). The introducing guide-wire is passed throughthecannulaintothe pharynx,a valveis attached by its ‘string’ and then pulled through retrogradely into the fistula (Fig. 55.4). Valve seating is helped by combined gentle traction on the tracheal flange of the valve with a fine artery forceps and asynchronousrotating movement. Postoperative feeding is then via a standard nasogastric tube. 7 In patients at high risk of woundbreakdown,the technique of primary TEP with stenting of the fistula and deferred fitting of the prosthesis is employed, as for the Blom-Singer prosthesis. In such cases, an artery forceps can be guided through the lumen of the Provox cannula as itis slowly withdrawn anda 12-14 FG Ryle’s tube passed through the fistula, as previously described. 8 The avoidance of a tight, hypertonic PE segment is vital to the success of SVR. In many cases, the upper oesophageal region feels tight when the index finger of

ployed. However, a tight vertical or T-shaped closure may predispose to stricture, especially when postoperative RT is planned. To produce a relaxed, widely patent pharynx,horizontal closure (as in pyloroplasty) may be preferrable. Thelateral margins of thetriangular pharyngeal defect may be gently distractedwithstay sutures, and with neck flexion (and occasionally mobilisation of a superior, tongue-base flap) horizontal closure is usually possible. Inverting 310 Vicryl sutures are used (interruptedorcontinuous Connell),with loose closure of the preserved inferior constrictors and tongue-base muscles as a second reinforcing layer (Fig. 55.5). St

Fig. 55.4 Primary tracheo-oesophageal puncture-Provox

technique.

the surgeonis gently inserted into thelumen. If this is so, then the circular upper-oesophageal muscle fibres should be divided down tothe submucosa to release any constriction.This myotomy shouldextendfromthe level of the TEP inferiorly, up to the level of the pharyngeal closure superiorly. Alternatively, dissection and then division of branches of the pharyngeal plexus to denervate the muscle may be performed (Singer et al., 1986). These measures should prevent a hypertonic PE segment developing postoperatively. Pharyngeal closure

This is performed as for routinelaryngectomy, but again it is vital to prevent stricture or hypertonicity if SVR is to be successful. If sufficient pharyngeal mucosa is present, then a T-shaped or vertical closure can be em-

1 Keep the patient nil by mouth (NBM) for 7-10 days and feed via the stoma-gastricRyle’s tube; then progressively reintroduce fluids, soft diet and normal diet as tolerated. 2 Once normal feeding is established, the fistula may be sized, using a Blom-Singer voice-prosthesis sizer, and an appropriate voice prosthesis is fitted (16FG BlomSinger duckbill or low-pressure prosthesis, sizes 1.43.6 cm). Alternatively, the fistula may be progresively dilated and the new long-term indwelling Blom-Singer prosthesis (20FG with special introducer and soluble gelatin insertion cap) may be fitted. 3 If aProvox prosthesis has been inserted at laryngectomy, valve cleaning (using a moist cytology brush) should commence on the first postoperative day, to prevent crusting or distortion of the valve flap. Voicing is not allowed until the wounds have healed and normal oral feeding has been reinstituted. 4 If fitting of theProvox valve has been deferred, thenpostoperativemanagement is the same asin 1 above. However, the Provox valve comes in only three sizes (6, 8 and 10mm lengths, 22 FG diameter). At first insertion, almost all patients require the standard 8mm size. 5 After fitting of anappropriate prosthesis, speech rehabilitation by an experienced speech therapist commences. An adhesive external tracheostomal valve may also be fitted, which obviates the need for finger occlusion of the stoma on exhalation when speaking. 6 If postlaryngectomy complications occur (e.g. wound infectiodbreakdown, salivary fistula, chest infection), then prosthesis fitting is deferred and the fistula is stented with a catheter. Similarly, RT may delay speech rehabilitation because of peristomal soreness, crusting and oedema.

Surgical VoiceRestoration

40 I

Fig. 55.5 Horizontal pharyngeal closure.

Complications

Complications of primary TEP arethose of laryngectomy, plus those related to the additional fistula and prosthesis, and general complications following major surgery (e.g. pneumonia, wound infection, neck haematoma, deep vein thrombosis (DVT), etc.). Specific complications include the following: 1 tracheostomal stenosis; 2 salivary fistula; 3 fistula granulation and/or closure; 4 salivary leakage through or around prosthesis; 5 aspiration of prosthesis (not permanently indwelling prostheses). ec

Preparation

Anaesthesia Theoperation is performedunder GA, using an armouredJ-shaped laryngectomy anaesthetictube (e.g. Rusch Laryngoflex). This tube can be taped to thechest in the midline to lie away from the operative field, and may be intermittently removed (after preoxygenation) to allow access to the stoma.

Antibiotic prophyla~is Prophylactic cover is advisable when pharyngeal myotomy is performedas an adjunct to simple TEP,

in order to protectagainstinadvertent breach of the pharyngeal mucosa with salivary contamination. Metronidazole and acephalosporin (e.g. cefuroxime) or Augmentin (amoxicilli~clavulanate) areacceptable options.

Position The patient is positioned supine with the head extended on a flexed neck, as for oesophagoscopy. Procedure

1 An illuminated bronchoscope or oesophagoscope is passed into the oropharynx and thenadvanced past the tongue base into the upper oesophagus. Any narrow or strictured area is gently dilated with bougies, and the scope is passed down to the level of the tracheostome. 2 The scope is rotated through 180" so that the bevel is facing anteriorly to transilluminate the posterior wall of thetrachea.The bevel will thenalsoprotectthe pharynx from the scalpel blade and/or trochar used to perform the TEP (Fig. 55.6). 3 Occasionally, after previous RT and/orcomplex pharyngeal reconstruction, itmay be difficult to pass the rigid scope downto the level of thetracheostome. A flexible paediatric gastroscope (e.g. Olympus XP20-diameter 6.6mm)can be passed under direct vision, a flexible guide-wire introducedthroughthe scope, the scope withdrawn and the pharynx then dilatedwith complete safety, using perforateddilators

Fig. 55.6 Transillumination of stoma.

threaded over the guide-wire. Thistechnique allows subsequent rigid instrumentation in almost all cases (A. Batch, pers. comm.). 4 A transverse incision is made into the posterior tracheal wall in the area illuminated by the bevelled tip of the endoscope, which is maintained firmly against theparty wall, using the left hand.The blade will pass through to the underlying metallic lumen of the

scope. The incision lies approximately 1cm below the mucocutaneous junction in the midline (Fig. 55.7). 5 A flexible Teflon trochar and attached 14FG Ryle’s tube (A.D. Cheesman, CharingCrossHospital, pers. comm.) is then passed throughthe incision intothe lumen of the oesophagoscope and, by advancingthe trochar andsimultaneously withdrawing the endoscope, the trochar and tube are delivered through the mouth (Fig. 55.8). 6 Alternatively, the Blom-Singer TEP set may be employed. This comprises a small, curved trochar with a Teflon sleeve, which is inserted in a similar fashion to make the initial TEP. The trocharis then removed and a guide-wire, attached to atapered silicone catheter is passed via the sleeve into the oesophagoscope. Traction on the wire and gentle dilatation of the puncture with the tip of a fine, curved artery forceps allows thesilicone catheter to be drawn up the oesophagoscope and out through the mouth (Figs 55.9-55.11). 7 A further technique employs a modified pair of abdominal forceps (TE forceps-Down’s Surgical), which areintroducedintothepharynxunder direct vision, alongside a pharyngoscope. The forceps is then advanced to the level of the stoma and the tips are angled to indent the posterior tracheal wall, allowing secondary TEP to be performed in a similar fashion to primary TEP (Rhys-Evans, 1991). 8 Whichever technique is employed, thecatheter

Fig. 55.7 Placement of tracheooesophageal puncture.

Surgical ‘Voice Restoration

403

further down the oesophagus under direct vision. This can be combinedwith slow tractiononthecatheter externally at thestoma in order to pass thecatheter inferiorly-paticularly when the catheter forms a tight loop at the level of the stoma. 9 Thecatheter is secured to the skin with adhesive tape, and spigoted to prevent reflux of gastric fluid. 10 Fistula sizing and fitting of an appropriate prosthesis

Fig. 55.8 Advancement of trochar.

Fig. 55.10 Inserting guide-wire.

Fig. 55.9 Tracheo-oesophageal puncture using trochar and Teflon sleeve.

stenting the TIE fistula must then be reversed and passed down the oesophagus (in a similar fashion to passing a nasogastric tube) by using an anaesthetic laryngoscope and Magill forceps. A pharyngoscope and straight oesophageal grasping forceps may then be used to advance the presenting loop or ‘knuckle’ of the catheter

Fig. 55.11 Traction on guide-wire draws catheter superiorly.

404

Fig. 55.12 Tracheo-oesophageal puncture.

supplied andtomaketheTEPapproximately1cm belowtheposteriortracheocutaneousjunction.The trochar passes intothe bevelled mouth of theoesophagoscope, as previously described, and an introducer is then fed through the cannula and delivered through the mouth as the scope is withdrawn. If preferred, the introducer is rigid enough to be passed up the pharynx after withdrawing the scope. An 8 m m Provox valve is then attachedto the fixation point at the end of theintroducer by its ‘string’, and the valve is pulled down through the pharynx until the string emerges through the fistula. The cannula in the fistula is thenwithdrawn. Do not puli hard on thestring at this pointin an attempt to seat the valve; this will damage the valve or fistula, or both.

Introducer passed through trocar and up pharyngoscope

Fig. 55.13 Trochar inserted into pharyngoscope.

Fig. 55.15 Valve withdrawn into pharynx.

Fig. 55.14 Prosthesis attached to guide string.

can proceed after 24-72 h, depending on thepatient and the speech therapist. 11 T o insert an indwelling Provox valve(Figs 55.1255.151, it is advisable to use the trochar and cannula

Fig. 55.16 Final positioning of prosthesis.

Surgical Voice Restoration

40 5

care not to enter the subcutaneous pharynx. 2 The incision (Fig. 55.17) should be made on the side opposite to a previous neck dissection, as the sternomastoid muscle is a useful landmark and also protects the carotid and IJV. Similarly, the side on which the thyroidlobehas been preserved at laryngectomy (if known) should be avoided, as thevascular and adherent thyroid remnant may complicate the approach.

Procedure

Fig. 55.1’7 Pharyngeal myotomy-incision.

12 Thetracheal flange of the valve should be gently grasped withmosquito forceps as it appears through the fistula. The valveis seated by combinedtraction and rotation until it flicks into place (Fig. 55.16). The string is then cut to free the introducer, and the valve is orientated upright in the fistula. Voicing should start immediately the patient returns to the ward from theatre. Pharyngeal myotomy

This may be necessary as an adjunct to secondary TEP, inorder to relieve hypertonic or spastic pharyngeal muscle function, which would impede or prevent successful SVR..It is appropriate to voice rehabilitation using either prosthesis type (non-indwelling or indwelling).

l Careful elevation of skin and platysma1 flaps allows identification and dissection of the anterior border of sternomastoid. 2 Cautious sharp dissection, alternating with frequent deep palpation, will identify thepharynx medially (stentedwitha 32FG tube) and the pulsatile carotid laterally. Note that the carotid sheath and IJV may be closely adherent tothe lateral pharynx and/orencased in fibrosis, particularly in the irradiated neck. 3 Sharp dissection should open a plane medial to the carotid (see Fig. 55.1), which may then be developed with blunt swabor finger dissection to enter theplane of the pre-vertebral fascia retropharyngeally. This is usually an unscarred area and a further landmark. 4 Rotation of the pharynx by the assistant exposes the posterior surface, and the tube within the lumen is simultaneously pushed towards the operator. This provides resistance to incise on to whenperformingthe myotomy (Fig. 55.18). The tight circular muscles of the pharynx and upper oesophagus are divided with a no.

Preparation

1 Following secondary TEP as above, a large-diameter (32FG) gastric tube is passed into the upper oesophagus, to act asa rigid stent in the lumen and to aid in the identification of the pharynx in the operated and irradiated neck. 2 The neck is extendedwiththepatient supine, the shoulders raised with a sandbag and the head supported ina head ring. The skin is preparedwithasuitable antiseptic (e.g. aqueous chlorhexidine) and the patient draped with towels to exclude the mouth from the operative field. Antibiotic prophylaxis is given. Incision

1 The previous Gluck-Sorensen laryngectomy incision is reopened from below the angle of the mandible superiorly to the supra-stomal area in the midline, taking

Fig. 55.18 Pharyngeal myotomy

406

Chapter 55

10 blade down to, but not through, the mucosa, from the tongue base to thelevel of the stoma.Some surgeons use operating loupes or the microscope to ensure complete division of all constricting fibres. 5 The upper and lower limits of the myotomy are conveniently marked with Ligaclips, which can be identified subsequently during radiological investigation. Closure

1 A suction drain is placed in the parapharyngeal region to prevent haematoma, or to drain saliva should any fistula develop. 2 The wound is closed in layers, using 310 Vicryl, 410 nylon and Steristrips to support the skin.

and rarely affect subsequent voice acquisition (Scott et al., 1993).

l Minor wound infection. 2 Haematoma formation. 3 Aspiration of prosthesis. The more serious complications are related to difficulties in endoscopy andlor inexpert tracheal puncture. 1 Oesophageal perforation. 2 Parapharyngeal abscess. 3 Mediastinitis. More commonly, a small salivary leak develops, which is managed conservatively by continued suction drainage, tube feeding and antibiotics, and speech rehabilitation is not adversely affected (Scott et al., 1993).

References Postoperative management

1 Prophylactic antibiotics are continued for 24 h (three doses) but may be reintroduced if haematoma or salivary fistula develops. 2 A regular antiemetic (e.g. prochlorperazine or metaclopramide) should be given for thefirst 24-48 h to prevent vomiting and rupture of the weak pharyngeal mucosa. 3 The suction drain is removed after 24-48 h. 4 The patient should be kept NBM for 2-S days and feeding maintained via the stoma-gastric catheter. Diet is then reintroduced progressively, from fluids, through soft diet to full diet as tolerated. 5 Sutures are removed after 5-7 days (7-10 days in an irradiated neck). 6 The fistula issized andanappropriate prosthesis is fitted after removal of sutures and once normal diet is being tolerated. Speech rehabilitation then commences. Complications These are usually minor, affect less than 20% of patients

Baugh RF, Lewin JS & Baker SR (1987) Preoperative assessment of tracheoesophageal speech. Laryngoscope 97, 461-6. Cheesman AD, Knight J, McIvorJ & PerryA (1986)Tracheooesophagealpuncturespeech: an assessmenttechniqueforfailed oesophageal speakers. J.Laryngol. Otol. 100, 191-9. Hamaker RC, Singer MI, BlomED & Daniels HA (1985) Primary voice restoration at laryngectomy. Arch. Otolaryngol. 111, 182-6. Hilgers FJM & Schouwenburg PF (1990) A new low-resistance self retainingprosthesis(Provox)for voice rehabilitationaftertotal laryngectomy Laryngoscope 100, 1202-7, McIvor J, Evans PF, Perry A & Cheesman AD (1990) Radiological assessment of post-laryngectomy speech. Clin. Radiol. 41, 312-16. Rhys-Evans P (1991) Tracheo-oesophageal puncture without tears: the forceps technique. J.Laryngol. Otol. 105, 748-9. Scott PMJ, Bleach NR, Perry AR & Cheesman AD (1993) Complications of pharyngeal myotomy for alaryngeal voice rehabilitation. J.Laryngol. Otol. 107, 430-3. Pharyngealplexus Singer MI, BlomED & HamakerRC(1986) neurectomy for alaryngeal speech rehabilitation. Laryngoscope 96, 50-3.

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PHILIP J. ROBINSON

Introduction Open biopsy of a suspicious neck node, or of a mass in the head and neck, remains an essential diagnostic manoeuvrebutshould be deferred, absolutely, until an exhaustive diagnostic work-up has been completed in an effort to detect the primary lesion. All patients presenting with a head and neck mass should undergo a full ENT assessment. In many cases a careful history will elicit symptoms related to a primary site within the upper aerodigestive tract. In asymptomatic patients presenting with a neck mass, the initial clinical ENT examination, alone, will detect 65% of the primaries (Martin & Romieu, 1952). Overall, a primary site can eventually be found in all but 10-15 % of patients presenting with a neck mass after an exhaustive work-up and careful follow-up over many years. The advent of increasingly reliable fine-needle aspiration cytology (FNAC) has greatly reduced the necessity foropen biopsy of neck masses. FNAC will usually define the problem (tumour versus in~ammation) and identify cell type and tissue of origin. In a report of 500 head and neck lesions the diagnostic accuracy of FNAC was 94.5% (Young et al., 1981). This technique is also virtually free of tumour seeding (Sinner & Zajicek, 1976). Open biopsy of a cervical lymphnodecontaining squamous-cell carcinoma (SCC) has not been shown to affect survival time, but it may delay appropriate treatment of the undetected primary and it is associated with certain complications, including fungation, wound necrosis, local recurrence and distant metastases (McGuirt & McCabe, 197’8; Gooder & Palmer, 1984). Furthermore scarring makes subsequent assessment of the neck more difficult (Shaw, 1970).

The differential diagnosis of cervical lymphadenopathy includes benign lymphoid hyperplasia, lymphoma, metastatic carcinoma, mycobacterial infection, toxoplasmosis and otherviral, bacterial and fungal infections (particularlyinimmunocompromisedpatients). The differential diagnosis also includes thyroid tumours, salivary-gland tumours, carotid-body tumour, branchial cyst and neurogenic tumours.

Indications Open biopsy should be considered only after an exhaustive diagnostic work-up (see below), including clinical examination, radiological studies, panendoscopy and FNAC, has failed to reveal a diagnosis.

1 Failure of diagnostic work-up toestablish a diagnosis.

2 Cytology suggestive of lymphoma, where histological architecture is still necessary for classification and treatment planning. In this situationopen biopsy can be coordinated with bone-marrow aspirationand trephine. 3 Children: cervical lymphadenopathy is very common in children. However, an enlarging neck node, symptoms and signs of systemic disease orabnormal test results (see below) are indications for open biopsy. Occasionally, parental anxiety is such that itis necessary to remove the offending lymph node. 4 HIV/AIDS patients: cervical lymphadenopathy is present in about20% of patientswith AIDS/AIDSrelated complex (Davis et al., 1988). Open biopsy is only indicated in thosepatientswherethenode is tender or enlarging and where theFNAChas been unhelpful. It is not indicated in the HIV or AIDS patient 409

410

Chapter S6

withnon-tender or non-enlarging nodes who have persistent generalised lymphadenopathy. FNAC will enablea diagnosis to be madeinmost cases with enlarging or tender nodes, enabling specific treatment such antituberculous as chemotherapy to be commenced. 5 Tuberculosis: fine-needle aspiration with samples sent to cytology and microbiology combined with a Mantoux skin test will usually allow the diagnosis of mycobacterial adenitis to be madewithout recourse to open biopsy (Davis et al., 1993). However, where there is any doubt about the diagnosis, open biopsy will provide material for histology and further microbiology. Excision of the lymph node may be necessary to treat atypical mycobacterial infection (Mycobacterium avium i~tracell~lare), which is frequently resistant to Chemotherapy.

only at right angles to the nerve and notin theline of the nerve. Supraclavicular nodes may indicate metastatic spread from outside the head and neck and therefore a thorough examination of breasts, bronchus, gastrointestinal tract and kidneys is required. In all cases a search is made for any other sites of lymphadenopathy and for hepato- or splenomegaly.

Preoperative managemen

In every case a full blood count with differential and erythrocyte sedimentation rate (ESR) is requested.

All patients presenting with a mass in the headand neck should undergo a full ENT assessment. History

A careful evaluation of symptoms referable to the upper aerodigestive tract, especially hoarseness, dysphagia, pain, otalgia, nasal obstructionand bleeding, is undertaken. Systemic symptoms, such as nightsweats, malaise and weight loss, are sought. A past history of heavy smoking and alcohol intakeis significant. Possible contact withTB and HIV risks should be borne in mind. Examination

A full ENT examination,takingparticularcare to examinethepostnasal space, oral cavity, posterior third of the tongue, tonsil, larynx, pharynx and thyroid. This examination is supplemented by fibre-optic rhinolaryngoscopy. The position of the node is a guide to the likely site of the primary. The size, positionandcharacter of thenode(s) are recorded and N staging established. A hard, fixed mass is suggestive of SCC and single or multiple rubbery nodes are more suggestive of a Hodgkin’s lymphoma. Pulsation within the mass should alert one to the possibility of a carotid-body tumour and is an indication for further investigation with an arteriogram or a magneticresonance arteriogram. A vagal schwannoma may present in a similar way to an enlarged lymph node but is fixed to the underlying nerve and is therefore mobile

Fine-needle aspiration cytology

Aspiration samples are taken in every case, except in young children, and sent for cytology and to microbiology; the possibility of acid-fast bacilli must be mentioned on the request form. Blood tests

Mantoux skin test

In any case where there is suspicion of tuberculosis.

1 Chest X-ray. 2 Sinus X-ray. 3 Barium swallow is indicated where there is suspicion that the node represents a metastasis from a primary withinthehead and neck. There is alsoa significant incidence of synchronous primary tumours within the upper oesophagus. 4 CT is very useful both in evaluating the neck nodes and in searching for the primary site. If performed, it should always be done before any biopsies are taken. The following CT signs suggest that a cervical node is likely to be positive for tumour: (a) greater than 1.5cm diameter; (b) non-enhancing or heterogeneous nodes; (c) ill-defined or irregular border; (d) groups of three or more nodes, 0.6-1.5 cm, with ill-defined or juxtaposed borders. The following CT signs suggest that the node is more likely to be negative for tumour: (a) less than 1.5 cm diameter; (b) discrete; (c) sharp margins; (d) virgin fascial planes around the carotid artery.

Lymph-nodeBiopsy in theHeadandNeck

Endoscopy

If the above management has failed to reveal a primary site and/or to make a diagnosis, panendoscopy is indicated. This should be done by the surgeon who will be responsible for the further management and should include direct laryngoscopy, direct pharyngoscopy, rigid oesophagoscopy, bronchoscopy and examination under anaesthetic (EUA) of thepostnasal space, oral cavity and oropharynx. Biopsies are taken from any suspicious areas and, in the absence of an obvious primary, random biopsies are taken from the fossa of Rosenmuller, the posterior wall of the postnasal space, the posterior third of the tongue after careful palpation and the pyriform fossa, and the ipsilateral tonsil is removed for serial sectioning by the histologist. Management strategies

The management strategy used will depend on whether the planned further treatment for an SCC is radiotherapy or a radical neck dissection. 1 Panendoscopy and proceed to open biopsy of the cervical node, under the same anaesthetic, if there is no sign of a primary tumour. Thisstrategy is appropriate if, when histology reveals an SCC within the lymph node, further treatment would be radiotherapy alone to the neck and potential primary sites. If multiple nodes are present, it would be usual to plan a radical neck dissection, followed by radiotherapy to the potential primary sites and, where indicated, to the neck as well. 2 Panendoscopy andawait results of therandom biopsies. If these results are negative, the patient would undergo a further anaesthetic and open biopsy of the cervical lymph nodewith frozen-section histology; if this shows SCC one would proceed to a radical neck dissection underthe same anaesthetic. Frozen section allows diagnosis of cell type in all but 1.2% of cases, but much moreinformation is available aftera paraffin section is done with tumour surface markers and electron microscopy (Remsen et al., 1984). The relevant merits of the subsequent managementstrategies and the use of radiotherapy are beyond the scope of this chapter and readers are referred for further readingto Liepzig et al. (1981) andJesse et al. (197’3). Management of cervical lymphadenopathy in children

Cervical lymphadenopathy is very common in children and usually associated withupperrespiratorytract

411

infections (URTIs). However,it is not uncommon to see a child with a persistently enlarged lymph node with anxious parents and GP. The child should undergo afull clinical assessment with particular regard to systemic symptoms such as weight loss, night sweats, malaise and examination for other lymphadenopathy and hepatosplenomegaly. A full blood count and differential, ESR and chest X-ray should be done and a Mantoux test where there is any suspicion of mycobacterial infection. FNAC isvery helpful if age permits. The child is reviewed after 2 weeks with the results and re-examination by the same clinician. Open biopsy is indicated if there is any suspicion, e.g. rapid enlargement orabnormal test results; otherwiseit is usually satisfactory to reassure the parents and to arrange a review in 1 month, again by the same clinician.

Relevant anatomy The lymphatic drainage of the head and neck is into two levels: first a deep group, which forms the common drainage pathway, and second an intermediate group or superficial layer, which drains into the deep group. It is the deep group which is usually involved when a patient presents with a node in the neck. This group lies along the great vessels from skull base to clavicle and is covered by the sternomastoid muscle for much of its length. However, -the more superior nodes may present in the anterior triangle of the neck (e.g. jugulodigastric node) and the lower deep nodes may present behind the muscle in theposterior triangle. Thelocation of cervical lymph-node groups most frequently involved by metastases from different primary sites within the head and neck is shown in Fig. 56.1. The deep group of lymph nodes lies beneath the deep layer of cervical fascia and therefore it is necessary to divide skin, subcutaneous tissue, platysma, superficial cervical fascia and finally the deep layer of cervical fascia to reach the involved nodes. In lymph-node biopsy, the deeper structures of the neck, such as the great vessels, are rarely encountered, but a detailed knowledge of the anatomy is still necessary. However, it is the more superficial structures, such asthemarginalmandibular nerve and the accessory nerve, which are at particular risk.

Marginal mandibular nerve

The marginal mandibular branchof the facial nerve is at risk with any dissection in the submandibular region. The nerve leaves theparotidglandandruns in the

412.

Chapter S6

Fig. 56.1 Location of cervical lymph-node groups most frequently involved by metastases from named primary sites. (adapted from Scott Brown’s Otolaryngology, 1987, Kerr AG (ed.). With the permission of Butterworth-Heinemann.)

superficial layer of thedeep cervical fascia fromthe angle of the mandible to the mandibular notch, usually about 1cm below the mandibular body in a gentle arc (Fig. 56.2). The nerve is always superficial to the facial of the vessels and is always abovethelowerborder mandible, anterior to the facial vessels (Stern, 1992). Careful elevation of the skin flap in this region in a plane immediately below platysma will leave the superficial layer of deep fascia intact.Careful dissection of this layer of fascia with dissecting haemostats, as used in tracingthe nerve inaparotidectomy, will reveal the nerve. A facial nerve stimulator will help in finding the nerve, which canthen be isolated or avoided as necessary. ss

Fig. 56.2 Location of marginal mandibular nerve (adapted from Stern, 1992).

er

The spinal accessory nerve is at risk with any dissection in the posterior triangle. The nerve lies within the superficial layer of deep cervical fascia and so great care must be takenin elevating any skin flaps in the posterior triangle. The nerve is located by first identifying the position of Erb’s point, a point halfway between the mastoid process and the clavicle on the posterior border of the sternomastoid, wherea bundle of cervical cutaneous nerves emerge. An imaginary line is dravvn,from this point to thethyroidnotch (Fig. 56.3). The accessory nerve will emerge fromtheposteriorborder of the sternomastoid muscle within 2cm above this line and will courseacrosstheposterior triangle to enterthe anterior border of trapezius within 2cm below it. Care-

ful dissection within these boundaries in the superficial layer of deep cervical fascia with fine haemostats, aided by a nerve stimulator, will identify the nerve (Becker & Parell, 1979).

Operative technique The operative procedure should be carried out by the surgeon who will have responsibility forthefurther, p:qssibly surgical, management of thepatient.It is Aot a procedure that should be left to the most junior surgepnl

Lymph-node Biopsy in the Head and Neck

413

excised and the incision incorporated into a subsequent neck dissection. Where possible it should lie over the node and inthe lines of relaxed skintension. For a submandibular node, it should be at least 3cm below the mandibular margin to avoid the marginal mandibularbranch of the facial nerve. For a posterior-fossa node, it should be remembered that the accessory nerve courses fairly superficially and can be cut inadvertently in the first incision. rocedure

Fig. 56.3 Course of accessory nerve. (adapted from Becker GD and Parell GJ (1979) Technique of preserving the spinal accessory nerve during radical neck dissection. Laryngoscope 89, 827-3 1.)

Preparation

Preoperatively fully informed consent is obtained. The procedure is usually doneundera general anaestheticwithendotrachealintubation,butcan be done under local anaesthetic (LA) with sedation if the patient is unfit for a general anaesthetic (GA). If it is planned to use a nerve stimulator, LA is avoided and the anaesthetist should be asked not to paralyse the patient. Infiltration with 1:200000 adrenaline can reduce the bleeding, but the infiltration itself can distort the tissue planes and make it more difficult to find a small node. The patient is placed supine on the operating table. The neck is extended and a sandbag placed under the ipsilateralshoulder.Theplanned incision should be marked before the head is rotated. The head of the table is elevated to reduce bleeding. The skin is prepared in the standard fashion and the patient is draped. lncision

Careful planning is required to ensure that any incision will not compromise any future neck dissection. Readers are referred to Chapter 62 for neck-dissection incisions. The incision should be placed so that the scar can be

1 Skin incision, carried down through the skin, subcutaneous tissue and platysma. 2 Elevation of skin flaps, including platysma. In the submandibular region, the elevation of the flap should be precisely at the interface of platysma and the underlying fatty tissue. Judicial use of hand-held a electrocautery unit will reduce the bleeding and aid early identification of nerves. 3 Identification of the marginal mandibular nerve in the submandibular region. If the node is close to the course of the nerve, it is wise to identify the nerve in order to avoid inadvertent damage. The nerve runs within the superficial layer of the deep cervical fascia, lateral to the facial vessels (Fig. 56.2). Careful dissection of this fascia from over the submandibular gland, using fine dissecting haemostats in a similar fashion to tracing the nerves in a parotidectomy and supplemented by a facial nerve stimulator, will allow direct visualisation of the nerve so that it may be dissected free. Alternatively, the fascia may be divided at a level below the submandibular gland and elevated as a flap with the nerve within it, but thiscarries a higher risk of inadvertent damage. 4 Identification of the accessory nerve in the posterior triangle. If thenode is intheposterior triangle, it is frequently adjacent to the nerve. A detailed knowledge of the course of the nerve is required (Fig. 56.3), and identification and avoidanceare recommended. The nerve is found coursing across the posterior triangle in the superficial layer of the deep cervical fascia, often in a very superficial position and occasionally even adherent to skin. Erb’s point is identified, mid-way between the mastoid process and the clavicle, where the cutaneous cervical nerves emerge from the posterior border of thesternomastoid muscle. Careful dissection in the superficial layer of deep fascia of the posterior triangle will enable identification of the nerve, which can then be dissected free of the node. 5 The dissection is deepened to the deep cervical fascia, which is divided. For access to the jugular chain of lymph nodes, this is easily done along the anterior bor-

4-14

Chapter 56

der of sternomastoid muscle. Frequently, the node lies under the belly of the sternomastoid muscle and retraction is required to dissect the node free. Occasionally, it is necessary to split the fibres of sternomastoid, but this is less satisfactory. 6 Identification of the position of important structures in the neck. The pulsation of the carotid artery is noted andthe jugular vein identified, as well asanyother significant structures, such as cranial nerves. 7 Identification of the node. The mass is carefully palpated to confirm the diagnosis of lymphadenopathy and to exclude such masses as a carotid-body tumour, vagal schwannoma or branchiogenic remnants. If a carotidbody tumour is suspected, theprocedureshould be abandoned without a biopsy and the patient should be further investigated with arteriography. 8 Isolation of the node. The tissue around the node is carefully dissected free to enable an excisional biopsy where possible. When the node is part of a matted mass of nodes or where it is adherent to an important structure,it may be necessary to perform an incisional biopsy. 9 Removal of the lymph node. 10 Haemostasis is secured. Diathermy should only be used under direct vision, since it is possible to damage neighbouring structures with injudicious use. Closure and drainage

1 A vacuum drain may be placed if there is concern about oozing. If the cavity is small and dry, no drain is required. 2 The wound is closed in layers: the deep structures with 2/0 Vicryl, the platysma with plain 2/0 catgut or undyed Vicryl and the skin with staples or 310 Prolene. 3 The wound is sprayed with a protective spray, such as Opsite spray. No dressing is usually necessary.

Postoperative mana~ement 1 Routine postanaesthetic management. 2 Discuss findings and implications with the patient. 3 Day case or overnight hospital stay only. 4 Removal of clips or skin sutures at 5-7 days.

Complication intraoperative

l Haemorrhage from damage to great vessels. Ligation of the internal jugular vein may be required. 2 Carotid sinus reflex during dissection around carotid bifurcation. The anaesthetist should be warned when

dissecting in this area. Lignocaine injected into the tissues can reduce the reflex. 3 Air embolism from inadvertently opening the internal jugular vein or other large vein in the neck. A sucking sound is heard and there may be a machinery-type heart murmur with hypotension and arrhythmias. Treatment consists of quickly rolling the patient into theleft lateral decubitus position with head down. Aspiration of air from the heart or even thoracotomy may be required. 4 Pneumothorax, if dissecting low in the neck. If significant, this may require a chest drain. 5 Nerve damage. Particularly the marginal mandibular and accessory nerves but other cranialnerves, e.g. vagus and hypoglossal, are also at risk. Very rarely the brachial plexus, sympathetic chainor phrenic nerves can be damaged. Postoperative

1 Haematoma.

2 Wound infection. 3 Chylous fistula, if the thoracic duct is damaged.

Becker GD & Parell GJ (1979) Technique of preserving the spinal accessory nerve during radical neck dissection. Laryngoscope 89, 827-31. Davis JM, Chadburn A & Mouradian JA (1988) Lymph node biopsy in patients with human immunodeficiency virus infections. Arch. Surg. 123, 1349-52. Davis Prinsley JP, PR & Robinson PJ (1993) Cervical lymphadenopathy due to mycobacterial infection: a diagnostic protocol. J.Laryngol. Otol. 107, 614-17. Gooder P & Palmer M (1984)Cervical lymph node biopsy-a studyof its morbidity. J.Laryngol. Otol. 98, 1031-40. Jesse RH, Perez CA & Fletcher GH (1973) Cervicallymphnode metastasis: unknown primary cancer. Cancer 31, 854-9. Liepzig B, Winter ML & Hokansen JA (1981)Cervical nodal metastasis of unknown origin. Laryngoscope 91, 593-7. McGuirt WF& McCabe BF (1978)Significance of node biopsy before definitive treatmentof cervical metastatic carcinoma.Laryngoscope 78,594-7. Martin H & Romieu C (1952) The diagnostic significance of a lump in the neck. Postgrad. Med. J.11, 491-501. Remsen KA, Lucente FA & Biller HG (1984) Reliability of frozen section diagnosis in head and neck neoplasms. Larnygoscope 84, 519-24. Shaw HJ (1970) Metastatic carcinoma in cervical lymph nodes with occult primary tumour. J.Laryngol. Otol. 84, 249-65. Sinner WN & Zajicek J (1976)Implantation metastasis after percutaneous transthoracic needle biopsy. Acta Radiol. Dzagn. 17, 473-80. Stern SJ (1992) Precise localization of the marginal mandibular nerve during neck dissection. Head Neck 14 (4),328-31. YoungJEM,Archibald SD & Shier KJ (1981) Needleaspiration cytologybiopsyinheadand neck masses. Am. J. Surg. 142, 484-9.

S

Surgery is indicated for recurrent or persistent inflammatory conditions, e.g. recurrent sialadenitis, chronic sialadenitis, mucocele andranula(mucous extravasationcyst),submandibularductobstruction (traumaticor calculus) and neoplasia (benign and malignant). Surgery is contraindicated during acute inflammatory episodes.

Sialadenitis is diagnosed on historywithfeatures of recurrent, painful swelling of the submandibular gland, which may be exacerbated by eating. Calculus obstruction commonly results in a persistent swelling of the gland,withintermittentpainful episodes. Wharton’s duct calculi are often visible or palpable on bimanual examination. Intraglandular calculi are difficult to feel but are usually apparent on plain X-rays of the region. Mucous extravasation cysts have a classical appearance when they occur in the floor of the mouth, i.e. ranula (Latin diminutive meaning ‘small frog’; tbis is a reference to the cyst’s similarity to a frog’s soft underbelly). The ranula has a bluish, cystic appearance and usually fills the floor of themouthlateraltothe Submandibular duct. These cysts rnay extend through or behind the mylohyoid muscle into theneck, i.e. plunging ranula (Joseph & Davidge-Pitts, 1985). These may extend to any level in the neck up to the clavicle. Communication with the oral componentrnay be demonstrated by applying pressure to the neck, which results in bulging within the floor of the mouth. These cysts transilluminate brilliantly. A history of trauma to the

.

sublingual-gland area rnay be elicited, although this is uncommon. Smaller mucoceles of theminor salivary glands usually occur inareas where trauma is more likely; hence most are found on the lower lip mucosa. They may occur in anyarea where minor salivary glands occur. Tumours of the Submandibular and minor salivary glands are usually painless swellings present for months or years. Pain associated with neoplasia of these glands is suggestive of adenoid cystic carcinoma, with its propensity for nerve involvement. Most salivary gland tumours donot involve adjacent nerves except in advanced, malignant disease. CT scans are useful in assessing neoplastic conditions of these glands. Extent of the tumour, particularlyin the palate or parapharyngeal space should be assessed. Neck-gland involvement may be noted on the scan. MRI scans yield similar information, although theuse of both investigations is unnecessary in these conditions. Sialography is of little help in the assessment of these conditions. Fine-needle aspiration cytology is useful in differentiating benign frommalignanttumours of the Submandibular gland. Thisinformation is important asthe surgical approach differs. In cases wherethe cytology is equivocal or not available, intraoperative frozen section is of value, although pathological assessment rnay be difficult. Minor salivary-gland tumours involving oral mucosa are usually amenable to incisional biopsy for management planning.

Surgery of the submandibular gland places the marginal

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mandibular nerve, hypoglossal nerve and lingual nerve at risk. Themostconstantanatomicalrelationship of the marginal nerve is the mandibularnotch. The nerve crosses over on to the mandible at this point and runs forward. Itleaves the parotid gland at variable distances below the angle of the mandible, usually 1-2cm, and courses anteriorly below the border of the mandible to thearea of themandibularnotch and facial vessels (Stern, 1992) (Fig. 57.1). The hypoglossal and lingual nerves run alongthe floor of the gland. The hypoglossal runs inferior to the lingual nerve, from posteroinferior a position to anterosuperior.The lingual nerve is wider and loops down from a posterosuperior position. Traction on the submandibular gland pulls the lingual nerve inferiorly via its submandibular ganglion attachments. Thesubmandibular gland surroundstheposterior border of the mylohyoid muscle, which is easily identifiedby the direction of its fibres. These run obliquely from the hyoid anteroinferiorly to the mandible posterosuperiorly. The final point of note is the relationship between the submandibular duct and lingual nerve. The duct is ‘double-crossed’ by the nerve. Posteriorly the nerve loops down, crossing superficial/lateral to the duct; it courses anteriorly below and then deeplmedial to the duct. This relationship is particularly important during intraoral surgery for ranula and plunging ranula.

ec

ue

1 Most surgery is performed under general anaesthesia. The exceptions include small oral mucosal mucoceles and excisional biopsy of small (less than 1cm) mucosal tumours or incisional biopsy of larger mucosal lesions. 2 Prophylactic antibioticsarerequiredfor surgery to lesions involving the oralmucosa. They are notrequired submandibular-gland for surgery, although the submandibularductshould be ligated. Ampicillin or amoxil with flagyl is a reasonable choice. 3 Patient positioning. Submandibular gland surgery is performed with the patient supine, neck slightly flexed on the shoulders with support beneath the shoulders; the head is extended on the neck and turned away from the side of surgery. A similar position is useful forpalatal lesions. A Boyle-Davis gag or dental props are helpful.

Fig. 57.1 Marginal mandibular nerve. The nerve may be found anywhere within the shaded area.

Incision

Submandibular-gland surgery

Benign lesions may be approached by a curvilinear incision placed withinaskin crease below the gland. It should extend from the posterior margin of the gland to a point 1-2cm beyond the anterior border and include the platysma. The crease is usually below the inferior border of the gland and is thus further away, from the mandibular border (2cm or twofingers’ breadths) than is usually recommended. This is cosmetically acceptable and also avoidsdamage to themarginalmandibular nerve. Formalignantconditionsthe incision is prolonged posteriorlytowardsthemastoid and inferiorly along the border of the trapezius muscle. This results in a safe and cosmetically acceptable flap for neck dissection withsubmandibular-gland malignancy (Dissanayaka, 1990). An alternative incision for combined gland and neck dissection is to takea limbinferiorly from the horizontal incision over the sternocleidomastoid into the posterior triangle, curving on to the clavicle. Neck incisions are infiltrated with Por 8 (vasopressin) 1:40 or a bupivacaine-adrenaline mixture. Procedure

Submandibular gland: benign conditions

1 Superior skin flap is raised. Either of two approaches may be used. (a) The incision is continued onto the inferior border of the submandibular gland. Glandular tissue is identified. A gauze swab is placed on a finger and

ry of the S u b ~ ~ n d i b uand l ~ rMinor Salivary Glands the flap is bluntly dissected away from the gland up to the inferior border of the mandible. This protects the marginal mandibular nerve, which now lies on the undersurface of the flap. Silk retraction sutures are placed inthe platysma muscle and sutured to drapes. (b) Alternatively the flap is raised by sharp dissection immediately on theundersurface of the platysma muscle. This tissue plane is immediately abovethe marginal mandibular nerve, so extreme care is necessary near andanteriorto themandibularnotch, where the nerve courses abovethemandible.The nerve is then identified at the notch and dissected free. Cautery should be used with extreme caution. 2 The gland is grasped and retracted posteriorly. The anterior margin is dissected free fromthe mylohyoid muscle (identified by obliqueanteroposterior fibres). Theposteriorborder of this muscle is identified and retracted anteriorly with blunt a retractor, e.g. Langenbeck. The floor of the submandibular gland is exposed by this manoeuvre. 3 Importantstructuresare identified onthe floor, namely the hypoglossal nerve inferiorly and lingual nerve withsubmandibular ganglion superiorly (Fig. 57.2). 4 The gland is dissected away from these structures by blunt dissection (finger and peanut swab). The gland is freed from the submandibular ganglion after its attachments are cauterised. 5 The facial artery and vein may be ligated at the posterior margin of the gland and below the mandibular

417

notch. Alternatively, these vessels may be preserved and dissected away from the gland, with cautery and ligation of branches to the gland. 6 The submandibularduct is ligated and transected. Absorbable sutures (Vicryl) are satisfactory. Malignant conditions of the sub~andibulargland

The approach differs in that wide margins are required, although preservation of the marginal nerve is important where no clinical involvement is present. Wide dissection of thesubmandibular triangle is performed, including the floor of thesubmandibular gland. (The patient must be informed preoperatively of possible resection of hypoglossal and lingual nerves if involved by tumour.) Modified radical neck dissection (functional) (Joseph et al., 1985) or modified regional dissection is indicated in malignant conditions of the submandibular gland (Weber et al., 1990). Intraoral minor salivary glands

Tumoursare excised with wide margins, including periosteum. Bony palateshould be preserved where possible. Adenoid cystic carcinoma of the oralcavity is particularly liable to wide submucosalspread.Tumour-free margins are very important and frozen-section control should be utilised to achieve this. However, massive resections of the maxilla for adenoid cystic and other salivary-gland carcinomas have not improved the prognosis significantly. Combined radiotherapyis extremely important in the management of salivary gland malignancies and should be considered in all cases, with thepossible exception of low-grade mucoepidermoid carcinoma.

CIosure/drainage/dressings

Fig. 57.2 Submandibular floor (left side). Mylohyoid muscle retracted anterosuperiorly. Anterior limit of gland retracted posteroinferiorly. Lingual nerve pulled into position below mandible by attachment to submandibular gland and ganglion. Lingual veins run the along floor with hypoglossal nerve.

1 The submandibular gland incision is closed in layers with 4 0 Vicryl sutures. 2 A small suction drain, e.g. 1/8 inch (3mm) Portovac, is inserted. 3 Closure of the platysma layer is importantand is responsible for the strength of the wound closure. 4 Skin is closed with subcuticular 4/0 plain catgut or skin clips. S Absorbing dressings areapplied and covered with adhesive tape or dressings. 6 Oral mucosal woundsare closed withinterrupted absorbable Sutures, e*g*VicrYl. Plain and chromicgut should not be used.

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Chapter 57

7 Palatal mucosal defects may be dressed withan acriflavine pack sutured in position. Graftsand flaps are not required to cover mucosal defects of the hardpalate. Defects greater than 50% of the hard palatemucosa will heal spontaneously. Where required local palatal flaps or grafts are useful. 8 Maxilla defects may be managed with prosthetics or pedicled, e.g. temporalis and free flaps.

Postoperative management Submandibular-gland surgery

Benign conditions

The drainis usually removed the day following surgery. Patients may commence eating immediately. They are discharged fromhospital onoral analgesics 1 day postsurgery. Marginal mandibular together with hypoglossal nerve function should be noted. The patient should be examined 2 weeks postsurgery for satisfactory healing. Malignant conditions

Hospital stay is usually slightly longer as a result of the neck dissection. If oral mucosa was not involved, eating may commence the next day. Drains are removed when secretions fall below 50 mu24 h. Patientsare mobilised on day 1 and may be discharged soon afterwards. Radiotherapy should begin as soon as woundhealing has occurred, i.e. approximately 2 weeks postsurgery. Intraoral lesions

Large palatal lesions are dressed with acriflavine, which remains in position for 10-14 days. Following removal, oralmouthwashes (normal saline) should be used frequently and oral Daktarin gel is useful.

Complications important most Thecomplication following submandibular-gland surgery is damage to the marginal mandibular nerve. This results in paralysis of the depressor anguli oris and labii inferioris. Flattening and inversion of the lower lip with loss of animation on smiling follow. This complication should not occur in surgery for benign lesions. Where surgery is performed for malignant conditions, the patient should be prepared for

possible resection of the nerve, although this is rarely indicated. Retraction on the flap by metal retractors may lead to neuropraxia and care should be taken if retraction is required. Hypoglossal and lingual nerve damage less is common. Further complications are rarely encountered.

Alternative procedure Mucous extravasation cysts

Small cysts of the oral mucosa and lips may be excised with the involved gland, which is usually very small and not identifiable. Ranula and plunging ranulas are successfully treated by drainage and excision of the sublingual gland. The submandibulargland is rarely involved and excision is not required (Joseph & Davidge-Pitts, 1985). Procedure

1 The submandibular duct is identified and a lacrimal probe inserted. The incision is made lateral to the duct, running anteroposteriorly, following infiltration of the mucosa with lignocaine 1% with adrenaline. The ranula is opened and drained, including any cervical plunging component, through the mouth. 2 Tissue lateral to theprobe is excised by blunt dissection (peanutswab) fromanteriortoposterior, where the lingual nerve is identified looping under the ductfromposterolateral to anteromedial. The tissue cleared by this method includes the involved sublingual gland. 3 Closure is achieved with interrupted Vicryl sutures (410 round-bodied needle). Drains are not required. Marsupialisationhas been recommended forranulas. This results in an unacceptably high recurrence rate (Joseph & Davidge-Pitts, 1985). The intra-oralremoval of the sublingual gland is a simple procedure and should be thetreatment of choice forranula and plunging ranula. Patients who have had previous surgery may require a cervical or submandibular approach. Large inoperabletumours of theminor salivary glands may respond to treatment with neutrons where this is available. Favourable results have been reported (Stannard, 1993). Incision biopsy of submandibular-glandtumours is not recommended. As malignant tumours of this area tend to have a poorer prognosis, fine-needle aspiration

Surgery of the Submandibular and Minor cytology or intraoperative frozen section should be used for correct planning.

1 Marsupialisation of ranulas is simple and quick but should be avoided because it is not successful. 2 Do not dissect plunging ranulas. They should be drained via the mouth andthe sublingual gland removed intra-orally. 3 The marginal mandibular nerve may loop down to the inferior border of the submandibular glandor it may remain above the mandible. Numerous branches to the platysma may be conhsed with the marginal branch. The marginal mandibular nerve may be very small. In view of these features regard all nerves in the area as the marginal mandibular nerve until proved otherwise.

Salivary Glands

419

References Dissanayaka L (1990) A modified single flap for neck dissection in oral cancer. Head Neck 12, 74-6. Joseph CA & Davidge-Pitts KJ (1985) Mucous extravasation cysts of the head and neck. South Afr. J.Surg. 23, 95-7. Joseph CA, Gregor RT & Davidge-Pitts KJ (1985) The role of functional neck dissection in advanced tumours of the upper aerodigestive tract. South Afr. J.Surg. 23, 83-7. Stannard C (1993) Neutron therapy imposes local control of salivary gland tumours. Presented at the Combined National Annual Spring Meeting of the South African Society of Otorhinolaryngology and theSouth African Headand Neck Oncology Society, Somerset West, South Africa, 18-22 October 1993. Stern SJ (1992) Precise localisation of the marginal mandibular nerve during neck dissection. Head Neck 14, 328-31. Weber RS,Byers RM, Petit B, Wolf P, Ang K & Luna M (1990) Submandibular gland tumours:adverse histologic factors and therapeutic implications. Arch. 'Otol. HeadNeck Surg. 116, 10.5560.

Excision of Thyroglossa cysts D. CARETH J O H N

thyroglossal duct. Fine needle aspiration cytology may aid diagnosis in equivocal or atypically sited lesions. Surgery is indicated for neck lumps which are clinically thyroglossal cysts for diagnostic confirmation, if they are cosmetically unacceptable or if theyare complicated by recurrent infection or inflammation. Acutely infected cysts should be treated byIV antibiotics, and incision and drainage avoided whenever possible, as scarring or fistula formation may occur. Definitive surgery is then performed once the acute infection has settled.

Preoperative management History and examination

Thyroglossal cysts may present at any age, butmost present before the age of 20as a firm (sometimes fluctuant) lump of variable size, which moves on swallowing and tongue protrusion, andwhich appears to be attached to the hyoid bone. Typically the lump is fixed deeply, but the overlying skin is freely mobile. The lump is situated in, or close to, the midline and may become acutely inflamed. The sex incidence is equal. The differential diagnoses include apyramidalthyroid lobe, a midline thyroidadenoma, midline lymph nodes and dermoid cysts. Unusually the cyst may be very lateral (mimicking a branchial cyst) or very high (mimicking a tongue tumour). Investigations

Athyroidisotopescan (99mTc)andloran ultrasound scan will ensure thatother thyroid tissue is present, confirm the diagnosis and demonstrate any associated

Relevant anatomy Early in fetal life the thyroid gland arises in the floor of thepharynx between two midline swellings, the tuberculum impar anteriorly and the copula posteriorly. It descends to its adult position, through tissues which will later form the tongue musculatureand hyoid bone. During descent it remains connected to the pharynx by the thyroglossal tract or duct (controversy remains as to whether a true duct with a lumen exists, and it will be referred to as a tract hereafter). The tract atrophies and its point of origin at the tongue base persists as the foramen caecum. A thyroglossal cyst is said to be a remnant of this tract, and such a cyst can thus occur anywhere between the foramen caecum and the final position of thethyroidgland (Fig. 58.1).The hyoid bone develops later and the tract usually comes to lie behind the bone, but may pass superficial to it or through it. The caudal portionof the tractmay persist as apyramidallobe of thyroid. A s thetract does not naturally communicate with the skin surface, a fistula originating from it is a secondary feature, representing surgical drainage, incomplete removal or infection and discharge.

Operative technique (Sistrunk’s procedure) (Sistrunk, 1928) Preparation

Anaesthesia General anaesthetic (GA) with nasotracheal intubation.

Excision of Thyroglossal Cysts

Fig. 58.1 The site incidence of thyroglossal cysts (from Maran, 1987).

Prophylactic antibiotics

Not normally indicated, unless the operation results in accidental opening of the mucosa of the laryndpharynx or tongue. Then a broad-spectrum antibiotic (including anaerobic cover) would be indicated. Patient positioning

421

3 Dissection of the tract (or the cyst) from the hyoid should not be attempted, but rather the central segment of the hyoid bone, which is associated with the tract, should be removed with the specimen. Using sharp dissection, the top and bottom of the hyoid bone are freed from their muscle attachments at two points either side of the midline, taking care not to injure the thyrohyoid membrane (Fig. 58.2). The bone may require stabilising with Allis forceps, and is then divided in these two places (Fig. 58.3),allowing the central part (about 12cm) between the lesser horns to be removed in continuity with thecyst. Medial to the lesser horns there is no danger of damaging the hypoglossal nerves. 4 Ideally a core of tongue musculature (including portions of mylohyoid, geniohyoid and genioglossus) containing the tract should then be removed, with theaid of cutting diathermy. It is important to realise that above the hyoid the tract passes backwards at 45" towards the foramen caecum. A finger in the mouth, pressing the tongue base forwards and upwards into the wound, is a useful manoeuvre to aid such dissection (Fig. 58.4), although the surgeon should be aware of the risk of introducing oral bacteria into the wound in this technique. In his original description Sistrunk stated that 'in temporarily disregarding the duct and coring out the tissues through which it passes, lies one of the secrets of cure, as the ductis so small and delicate that it is almost invariably broken ...if efforts are madeto dissect it out alone'. Alternatively, downward traction on the central portion of the hyoid bone with Allis forceps may define a conical tract of muscle and duct, which may be dissected and then ligated and divided.

Supine with the neck extended by a sandbag under the shoulders and the head supported in a head ring. incision

A horizontal skin crease at theupper margin of the cyst, so that the tract can more easily be followed upwards. If a fistula is present, then a horizontal incision should be made at that level, including the fistula in a skin ellipse. Procedure in stages

1 The incision is carried through platysma, and flaps are raised superiorly and inferiorly. The anteriorjugular veins (AJVs) are ligated and divided. 2 The cyst is identified by separating the strap muscles in the midline. The cyst is then mobilised, and in low cysts a tract can usually be identified passing upwards, intimately associated with the hyoid bone.

Fig. 58.2 The relation of the thyroglossal tract to the hyoid bone and the thyrohyoid membrane (from Allard RHB (1982) The thyroglossal cyst. Head Neck Surg. 5 , 134-46. 0 1982, reprinted by permission of John Wiley & Sons, Inc.).

monofilament sutures and Steristrips usually produce an excellent cosmetic result.

The neck should be watched for swelling. The drain is removed whendrainage ceases on aboutthe second postoperative day.

Fig. 58.3 Excision of cyst, tract and a core of suprahyoid musculature (from Hibbert, 1983 Rob ei- Smith's Operative Surgery. With permission of Chapman and Hall.).

Fig. 58.4 Excision of core of suprahyoid musculature aided by a finger over the foramen caecum. Note the 4.5" angle at which the tract passes backwards above the hyoid. (From Brown & Judd, 1961.)

The wound is closed in layers and a suction drain inserted with its exitinthe lower flap. Subcuticular

l Bleeding in combinationwitha blocked draincan result in neck swelling and airway obstruction (reopening the wound on the wardmay be life-saving). 2 Inadequate removal of the tract may result in recurrence, sometimes with afistula. This is probably because of extension of the tract tothe tongue base, and because of the presence of multiple tracts (Mickel & Calcaterra, 1983).The recurrence rate varies between different series, but is probably lower than 8% inthe classic Sistrunk operation, and as high as 85% if the middle part of the hyoid bone is not removed (Allard, 1982). Recurrence is usually apparent within afew months, but may take many years. Treatment is simple if Sistrunk's operationhasnot been performed-the body of the hyoid and a core of musculature are removed. If recurrence follows a Sistrunk procedure, the removal of cyst and tract may involve an anterior block dissection from thyroid isthmus to foramen caecum (Mickel & Calcaterra, 1983). 3 Rarely a mass which is clinically a thyroglossal cyst proves to be composed solely of ectopic thyroid tissue, and may represent the only thyroid tissue present. Removal thus results in hypothyroidism. It is said that 65'75% of patients with lingual thyroids have no other thyroid tissue. This presumablyrepresents complete failure of the gland to descend. Poor scar in a cosmetically unacceptable site.

Perhaps not all thyroglossal cysts require surgery. Of 17'5 patients at the Mayo Clinic who were not operated on for various reasons, follow-up of between 8 and 22 years showed that only 22% eventually came to operation(Brown & Judd, 1961). However, removal does allow histological confirmation of what would otherwise be an undiagnosed neck mass. Thyroid carcinomas (usually papillary)in ectopic thyroid tissue are rare, but well recognised. Some authors recommend that the incision be placed

Excision below the lump, asthis is cosmetically more acceptable. Ifthe cyst is very low in theneck, then adequateremoval of the tractwill require two parallel incisions, one at the level of the cyst and the other higher in the neck, with the cyst (and attached tract) being passed beneath the intervening bridge of skin.

References Allard RHB (1982) The thyroglossal cyst. Head Neck Surg. 5, 13446.

of

ThyroglossalCysts

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Brown PM &;;‘Judd ES (1961) Thyroglossal duct cysts and sinuses: results of radical (Sistrunk) operation. Am. J.Surg. 102, 494-501. Hibbert J (1983) Thyroglossal duct cyst. In: Dudley H and Carter D Operative Surgery, 4th edn. London, (eds) Rob 6 Smitb’s Butterworths, p. 406. Maran AGD (1987) Benign diseases of the neck. In: Stell PM (ed.) Scott-Brown’s Otolaryngology, 5th edn.London,Butterworths, V01 5, pp. 283-6. Mickel RA & Calcaterrra TC(1983) Management of recurrent thyroglossal duct cysts. Arch. Otolaryngol. 109, 34-6. Sistrunk W (1928) Technique of removal of cyst and sinuses of the thyroglossal duct. Surg. Gynecol. Obstet. 46, 109-12.

Branchial cysts and sinuses should normally be removed once the diagnosis has been made, especially in adults, where the cyst can be mistaken for a malignant lymph node with cystic degeneration. They present most commonly in early adult life, either as a simple mass in the neck or as an infected mass, but acyst can present at any age. Branchial sinuses almost invariably present in infancy unless an infected branchial cyst is allowed to rupture externally to become a sinus. Branchial fistulae will normally present in infancy or childhood, with a point of discharge in the neck. It is not necessary to remove the uncomplicated branchialsinus or fistula, but discharge fromthetract will make it desirable in early childhood.

Branchial cysts, sinuses and fistulae should not be excised when they are infected, asthe risk of leaving remnant tissue will be greatly increased, as will the risk of wound infection.

Any mass that is clinically abranchial cyst and that presents without infection should be subjected to fineneedle aspiration biopsy. This will confirm the cystic nature of the mass and enable the cyst contents to be sent for cytological examination to look for the rare case of a malignant lesion presenting as a cyst. Usually, after aspiration the mass will return within a week or so, but

occasionally it will disappear for a much longer period, Assuming the mass returns and cytology studies do not suggest malignancy, no further special investigation is needed. An infected branchial cyst should be treated initially with IV broad-spectrum antibiotics, after aspiration of the contents for bacteriological investigation. Occasionally the cyst will not return after successful treatment, but usually a cyst remains and should then be removed without any further special investigation.

These need no special investigation, but careful examination of the oropharynx shouldbe undertaken to look for an internal opening of a fistula around the anterior faucial pillar. Branchial-arch abnormalities can be associated with other familial developmental abnormalities, particularly of the middle and innerear and kidney (branchio-otorenal syndrome). These abnormalities should be excluded if there is a family history of branchial-arch pathology.

Branchial cysts usually arise from remnants of the second branchial arch or cleft (Fig. 59.1). Such cysts will usually present anterior to the sternomastoid muscle at about the level of the junction of the upper third and lower two-thirds. Cysts presenting higher than this may have originated from the first cleft, and lower than this from the third or lower clefts. The relevance of this is that first-arch cysts may have complicated deep tracts connected to the external auditory meatus(EAN) atthe bone-cartilage junction and closely related to the facial

Branchial Cysts, Sinuses and Fistulae

425

P r o ~ ~ ~ l a cantibiotics/steroi~ tic cover

In the uncomplicated case antibiotics and steroids are not necessary. Patient ~ositioning

The patient should be placed supine on the operating table, using extra shoulder support to slightly extend the neck, which should be rotated to the side opposite the lesion. A small amount of head-uptilt will aid haemostasis. The skin may be infiltrated with a vasoconstrictor if desired, but this is not essential.

Fig. 59.1 Representation of developmental branchial arches, clefts

Forbranchial cysts inthe mid to lower part of the neck, a skin crease incision about &"cm long over the lump is used. To avoid themarginalmandibular branch of the facial nerve, incisions should always be morethan 3cm below the angle andramus of the mandible. An incision in line withtheanterior border of sternomastoid will give better exposure of any deeper connections of the cyst, but postoperative scarring will be more likely than with a skin-crease incision, and hence should be avoided. For cysts in the upper part of the neck, which might originatefromthe first branchial arch, standard a parotidectomy incision

and pharyngeal pouches.

nerve (Fig. 59.2). The lower-arch cysts rarely have deep connections, but may have tracts intimately related to thecarotid-arterybifurcation. Sinuses or a cyst may occasionally open into the pharynx through one of the pharyngeal pouches, usually the first, which develops into the tonsil.

Anaesthesia

Branchial cysts, sinuses and fistulae should always, if possible, be excised under general anaesthesia. Althougha simple cyst with no deep connections might be easily excised under local anaesthesia, deep connections, with which it would be very difficult to deal under local anaesthesia, can never be excluded preoperatively.

Fig. 59.2 Representation of first-arch branchial cyst with track extending in close proximity to the facial nerve to the external auditory meatus.

-

426

Chapter 59

Fig. 59.3 Representation of dissection of a branchial cyst with deep tract extending between carotid bifurcation to the pharynx.

should be made, in order to expose the facial nerve if necessary. For branchial sinuses and fistulae, the initial incision should be an ellipse around the external opening. Further short transverse incisions up the neck may be required (see below) to follow the deep tract. Procedure

cyst is lessened withthe use of scissors and ‘blunt’ dissection. 4 If the deeper parts of the cyst are difficult to identify and dissect, gentle manipulation with a finger may free itupfurther. Alternatively, the cyst may be decompressed a little by aspirating some of its contents, using a thin-gauge needle, but this often results inrupture rather than controlled decompression, and should only be used as a last resort. 5 Most cysts will be easily removed in this manner, but in all cases a tract should be sought that might extend deeper into the neck. The route of such a tract would theoretically depend on its embryological origins, but will most commonly be found extending between the internal and external carotid arteries (Fig. 59.3),or up to the bony-cartilaginous junction of the EAM in the case of a first-arch cyst. The cyst should always be sent for histological examination to exclude the very rare branchogenic carcinoma or other malignancy.

Branchial sinus and fistula The inital elliptical incision is deepened to identify the sinus or fistula tract, and this is followed as high into the neck as possible towards the carotid bifurcation. If access becomes restricted, a further skincrease incision should be made higher in the neck to expose the tracthigher up. The tractshould be followed, if necessary, to its internalopeninginthe case of a fistula.

Branchial cyst

1 The initial incision is deepened through platysma to expose the sternomastoid muscle, and the skin flaps are raised in a subplatysmal plane. 2 A self-retaining retractorto keep the skin edges with platysma well partedshould be inserted. The cyst may become apparentstraightaway,butoften sternomastoid the will need to be retracted posterolaterally. In the case of afirst-branchial-arch cyst, it may not be so superficial and formal identification of the facial nerve should be made, as in a superficial parotidectomy. 3 Oncethe cyst is exposed, the superficial tissue surroundingitcan be separatedfromthe cyst fairly easily, using blunt-ended curved iris scissors. Care should be taken in the deeper part of the dissection, where the contentsof the carotid sheathwill be exposed, as may the accessory nerve if the dissection extends intotheposteriortriangle of the neck. Although some surgeons always recommend using a scalpel for dissection, the author feels that the risk of rupturing the

Closure/larainage/dressings After removal of the cyst and any tract, a suction drain should be inserted, the platysma closed with an absorbable suture and theskin closed in a manner of personal preference. Thewound is best covered witha clear, plastic, self-adhesive dressing material.

Postoperative management The drain can usually be removed the following day, with the patient being discharged later that day. Any remaining non-absorbable sutures or clips may be removed about the fifth postoperative day.

Complications If the cyst is high in the neck, the marginal mandibular nerve may be damaged, or even the facial nerve truhk in the case of a first-arch tract which extends to the EAM. With due care, injury to the major vessels should not

BranchialCysts,Sinuses occur. In looking for or dissecting out a deep tract, the hypoglossal nerve may be damagedas it passes under the occipital artery, the facial nerve may be damaged if the tract is extending to the EAM, and the accessory

and Fistulae

427

nerve is at risk in dissection extending posteriorly in the neck. If meticulous care is not taken to remove allthe cyst, sinus or fistula tract, recurrence is likely.

OLAS P. McIVO

History e

1 Primary thyroidal: differentiated thyroid carcinoma, medullary carcinoma,intrathyroidalanaplastic carcinoma (rare). 2 Secondary involvement: as part of surgical treatment for carcinoma of the larynx, hypopharynx, cervical trachea and oesophagus. 3 Ectopic parathyroid adenoma.

Multinodular goitre extending or arising retrosternally.

1 Solitary toxic nodule. 2 Graves’ disease.

Patients at higher risk of malignancy inasolitary nodule include children, the elderly, men, those who have previously undergone low-dose irradiation to the neck and patients with a family history of thyroidcarcinoma. Pain and increase in size of a long-standing nodule maybe due to recent haemorrhage but may also indicate malignancy. Hoarseness may indicate recurrent-laryngeal-nerve invasion. Gradual onset of dysphagia andstridorare more likely to be due to multinodular disease or thyroiditis, while rapid onset is usually due to anaplastic carcinoma. Hypertension, flushing and diarrhoea may indicate systemic features of medullary carcinoma. A compressive goitre may cause dyspnoea when lying flat or when elevating the arms above the head, while dysphagia is less common. Examination

This includes palpation of the neck to assess the thyroid gland and the jugular and paratracheal nodes, as well as assessment of vocal cord mobility.

For cosmesis.

Blood tests

Thyroid-function tests and serum calcium, phosphate and albumin are performed preoperatively.

1 Extrathyroidal anaplastic carcinoma of thyroid. 2 Thyroid lymphoma,

C hest X-ray

Onlythework-upforthesolitarynodule compressive goitre will be addressed.

and

This may detect pulmonary metastases, retrosternal extension and tracheal deviatiodcompression.

Thyroid nodule

Thyroid Surgery

429

C T scan. This is useful when retrosternal extrathyroidal extension is suspected.

or

Fine-needle aspiration cytology

Compressive goitre

This is the single most useful test. A skilled cytopathologist can distinguish between non-neoplastic and neoplastic lesions with a high degree of accuracy. The distinction between a benign and malignant follicular neoplasm is not reliable because capsular and vascular invasion, the hallmarks of malignancy, cannot be assessed cytologically. However,papillary carcinoma,themostcommon differentiated tumour,has characteristic nuclear features (intranuclear cytoplasmic inclusions and grooving) that may provide the diagnosis. Furthermore, whole papillae may be aspirated. Surgery is indicated when the aspirate shows malignant cells (papillary carcinoma, medullary carcinoma) or when there are features of a follicular neoplasm. Nodules producing non-neoplastic cytology in lowrisk patients can be observed and reaspirated at a later date. In high-risk patients the decision for surgery will depend on the clinician’s index of suspicion.

1 Respiratoryfunction tests with flow-volume loops may give an idea of the degree of airways compression, but these are surprisingly insensitive for many patients. 2 CT scan is again useful if there is significant retrosternal extension seen on the chest X-ray.

Imaging This is often unnecessary after an adequate cytological exammation. Ultrasound. Thereare no ultrasonographicfeatures that can reliably distinguish between benign and malignant lesions. Furthermore this modality is very userdependent. Ultrasound can determine whether a nodule is truly solitary or part of a multinodular gland, but the latter finding does not exclude malignancy. It can distinguish cystic lesions from solid, but few cysts are simple cysts. Most are complex withsolid components and represent degenerating solid lesions. Ultrasound’s real value in this situation is to guide the fine-needle aspiration of the solid component. Furthermore, it can be used to monitor the size of a lesion over a period of time. Scintigraphy. Isotope scanning determines the activity of the lesion in relation to the surrounding gland, butin the author’s opinion gives little added information to that obtained by cytology, with the exceptionof the hot nodule, which is very rarely malignant. The majority of cold lesions are benign, butapproximately 20%are malignant. Cold nodulesmust be aspirated for cytological examination.

The thyroid gland consists of two lobes and anisthmus, and weighs approximately 25g in the adult. It straddles the cervical trachea, with the isthmus at the level of the third and fourth tracheal rings and the superior pole overlying the cricoid cartilage and cricothyroid muscle. It is enveloped by a fine capsule, from which septa pass into the gland to separate the lobules. The pretracheal fascia also envelops the gland to form the ‘surgical capsule’. Dissection beneath this capsule and on the true capsule comprises the ‘capsular dissection’. The gland is adherent to the trachea by the surgical capsule, and in addition is suspended to thelateral surfaces of the cricoid cartilage, cricothyroid joint and upper tracheal rings by a thickening of the capsule known as Berry’s ligament. The recurrent laryngeal nerve on each side usually lies in thetracheo-oesophageal(TE) groove but may lie outside the groove, particularly on the right side. Each nerve passes up in loose areolar tissue posteromedial to the lobe and is variably but intimately related to the inferior thyroid artery or its branches, which run from lateral to medial whenthegland is retractedduring surgery. The nerve then usually passes behind but may pass between the fibres of Berry’s ligament to enter the larynx behind the cricothyroid joint (see Figs 60.3, 60.5 and 60.7). There is always a small branch of the inferior thyroid artery and small veins that course along Berry’s ligament, whichcanmake dissection of the nerve through the ligament hazardous. In approximately 1% of cases the right nerve is non-recurrent and is closely related to the inferior pole of the thyroid gland, as it passes lateral to medial directly from vagus nerve to larynx. The parathyroid glands aresmall (1X 3 X 6mm), soft and ovoid, and lie adjacent to the thyroid gland,usually within the surgical capsule. They are most easily recognised by their characteristic caramel colour but are often camouflaged by associated adipose tissue. Thetotal number of glands may vary between two and six or

430

Chapter 60

more, but there are usually an upper gland and a lower gland on each side. The upper gland is the more constant of the two and usually lies posterior to the nerve on the posterior surface of the superior pole, near the level of the cricothyroid joint. The inferior gland usually lies on the posterior surface of theinferior pole and anterior to the recurrent laryngeal nerve (see Figs 60.560.7), although it may not uncommonly be in the thymus and out of the surgical field. The external laryngeal nerve arises from the superior laryngeal nerve at the thyrohyoid membrane and passes down beneath the lateral border of the sternothyroid muscle and on the middle constrictor to run along the lateral surface of the cricothyroid muscle, which it supplies. In about 15% of thyroid lobes, the nerve is below the level of the superior pole and athigh risk of surgical damage. Thethyroidgland is supplied fromabove by the paired superior thyroid arteries and posterolaterally by the paired inferior thyroid arteries. The parathyroid glands are supplied by branches of the inferior thyroid artery.

Operative technique Thyroid lobectomy will be described. Total thyroidectomy requires a repeat of this procedure on the opposite side. Preparaltion

Anaesthesia

mandible above to the clavicles below. Mark outa skincrease incision two fingers’ breadths above theclavicles, extendingapproximatelyfrommidsternomastoid to midsternomastoid. Procedure in stages

Flap elevation

Elevate the skin flaps to the level of the thyroid notch superiorly and tothe suprasternal notchinferiorly in the subplatysmal plane. Suture the flaps to the skin. Separation of strap muscles

Completely separate first the sternohyoid and then the sternothyroid muscles in the midline, using monopolar pencil diathermy (Fig. 60.1). Use finger dissection to gently separate the strap muscles from the underlying lobe to be dissected. Do not performthis onthe contralateral side, so as to provide a virgin field should subsequent surgery be necessary on thatlobe. The straps should be elevated to expose boththesuperiorand inferior poles of the lobe. The assistant retracts the strap muscles throughout the remainder of the procedure for exposure to facilitate dissection. Occasionally, for large goitres, the strap muscles may need to be divided to provide access. Exposure of the trachea and mobilisation of inferior pole

Use blunt dissection witha

Lahey swab(‘peanut’ or

General anaesthesia via anasotrachealtubebrought over the patient’s forehead.Theanaesthetist is positioned near the feet of the patient so that the operative team have access to both sides of the head. Prophylactic antibiotics

TV antibiotics are given at induction only. Patient positioning

The patientis positioned supine, the neck extended by a pillow under the shoulders. The head is positioned in the midline on a small head ring. The bed is angled in the reverse Trendelenburg position. Incision

Prepare the skin and drape to expose the neck from the

Fig. 60.1 Division of the deep cervical fascia and separation of the scrap muscles in the midline with unipolar pencil diathermy.

Thyroid Surgery

43 I

obilisation of the superior pole

Your assistant must retract the strap muscles laterally and superiorly. Use onehandto retractthe lobe inferomedially with a swab while, with the other hand, dissecting the fascia off the superior pole with a Lahey swab. The superior thyroid artery and vein should be clearly seen. Dissect medial to the vessels to preserve the external laryngeal nerve and then ligate and divide the vessels close to the gland (Fig. 60.4). Identi~cation ofthe superior parathyroid gland

Withthe lobe retracted to theopposite side, gently dissect the fascia from the undersurface of the superior pole with a Lahey swab. The superior parathyroidgland usually lies at the level of the cricothyroid junction (see Relevant anatomy) (Fig. '60.5).

Fig. 60.2 Dissection of the inferior pole to display the trachea and inferior thyroid veins. A Lahey swab is an ideal dissection tool for this.

'pusher') to identify thetrachea below theisthmus and continue this dissection to mobilise the inferior pole (Fig. 60.2). Clear the loose fascia from the inferior thyroid veins for accurate identification, and ligate and divide them. Similar dissection laterally allowsligation and division of the middle thyroid vein.

Preservation of t e parathyroid glands and the recurrent laryngeal nerve

Use bipolar diathermy and small forceps to dissect and reflect the inferior gland on its vascular pedicle posteriorly from the thyroid lobe (Figs 60.5 and 60.6). Similarly, reflect the superior gland posteriorly from the thyroid,but always visualise therecurrent nerve. A

Identification of the inferior parat

The assistantshould use a large swabtoretract the lobe awayfromtheoperator(forceps placed on the lobe tend to cause bleeding and should be avoided). Use a Lahey swabto gently breakthe loose fascia on the undersurface of thegland in an endeavour to find the inferior parathyroid (see Relevant anatomy). Identification of the recurrent laryngeal nerve

Your assistant must provide good retraction. Dissect in the TIE region with a Lahey swab by sweeping in the direction of the nerve (Fig. 60.3). If the fascia is resistant, use a mosquito forceps to break it, by spreading the forceps in the direction of the nerve. Fig. 60.3 Identification of the inferior parathyroid gland (forceps) and the recurrent laryngeal nerve. A Lahey swab is swept in the direction of the nerve.

43 2

Chapter 60 thermy before division. Once the nerve is seen passing behind the cricothyroid joint, the remaining ligamentous attachments to the gland can be divided, using either ascalpel or bipolar diathermy. Stay on thecapsule of the gland and medial to the cricothyroid joint. Dissection of lobe from trachea and division of isthmus

Use a scalpel to dissect the lobe from the trachea across the midline and resect it atits junction with the opposite lobe to avoid a palpable lump in the midline. Oversew the stump (Fig. 60.8) and inspect the specimen for the presence of parathyroid glands. If any are present, consider dicing the tissue into 1mm sections and reimplanting them into small pockets made in the sternomastoid. In thesituation of thyroidectomyfor differentiated thyroid cancer, always obtain a frozen section on the tissue to be reimplanted, to avoid implanting tumour.

Fig. 60.4 Dissection of the superior pole. The superior thyroid artery and vein are cleared of fascia and a plane is developed between them and the cricothyroid muscle and external laryngeal nerve.

Obtain haemostasis and insert a suction drain through the skin in the midline inferiorly, placing it in the thyroid bed butawayfromtherecurrent laryngeal

mosquito forceps passed along the course of the nerve facilitates dissection. Note: if the parathyroid glands have not been adequately identified, then a dissection beneath the envelopingpretracheal fascia and thetrue capsule of the gland, the so-called ‘capsular dissection’, is essential to minimise the risk of their being present on the operative specimen. While it is not acalamity to lose the parathyroids from oneside of the neck, the surgeonwho has done this unnecessarily creates an even greater challenge for him/herself if the other side needs subsequent dissection. Separation or division of Berry’s ligament

Once the parathyroid glandshave been reflected, pass a mosquito forceps along the line of the nerve to identify its relationship to Berry’s ligament. Usually a capsular dissection will allow the gland to be cleared from the ligament with full protection of the nerve. If the ligament needs to be divided, insert the forceps along the path of the nerve and gently open them. Under direct vision, divide the ligament (Fig. 60.7’). Any small bloodvessels should be carefully cauterised with bipolar dia-

Fig. 60.5 Dissection of the parathyroid glands. The glands are reflected off the thyroid gland with preservation of their pedicles. A mosquito forceps develops a plane of cleavage and the intervening tissue is cut.

Thyroid Surgery

Fig. 60.6 Bipolar diathermy dissection of the inferior parathyroid gland. Dissection begins on the edge distal to the vascular pedicle.

433

aftertotal thyroidectomy, which putsbothrecurrent laryngeal nerves at risk. Monitor wound drainage, particularly over the first 12h. The wound must also be observed, as heavy bleeding can be too much for a suction drain. Staff must be aware of the need to release both superficial and deep sutures and to evacuate the haematoma immediately in the event of impending airway obstruction. Whentherehas been bilateral dissection, even if one side wasdone previously, calcium status must be monitored for the first 2-3 days. The management of hypocalcaemia is discussed under Complications. After partial thyroidectomy, thyroid functionis tested a month after operation to determine whether any supplementation is required. Patients who have undergone total thyroidectomy can begin thyroid supplements in the first week. However, patients who have had total thyroidectomy for differentiated thyroid cancer are not started on thyroid supplements untilafter an isotope scan, between 4 and 6 weeks postoperatively. This is to ensure that thyroid-stimulating hormone (TSH) levels are high in order to increase the uptake of isotope by residual thyroid tissue and metastases.

Complications Operative Damage to recurrent laryngeal nerve

This is usually because of failure to adequately identify

Fig. 60.7 Division of Berry's ligament. A mosquito forceps is passed along the nerve and opened, allowing safe incisionof the ligament.

nerve. Reapproximate the strap muscles over the drain from superior to inferior so that the drain exits from the thyroid bed inferiorly. Close the subcutaneous layer with 310 Vicryl and the skin with 4/0 nylon sutures.

Postoperative management In recovery, note whether the patient has a normal voice and cough. The airway must be assessed, particularly

Fig. 60.8 Operative bed. The lobe and entire isthmus have been resected.

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Chapter 60

the nerve. Always consider the possibility of the right nerve being non-recurrent.Thewoundshould be reexplored if there is the possibility of a tie having been placed on thenerve. If the nerve was identified throughout the dissection, then it is likely that it is neuropraxic and steroids may hasten recovery. Damage to external laryngeal nerve

This may be from failure to develop a plane between superior-pole vessels and the cricothyroid muscle. The vessels should be clearly identified and cleared of fascia before ligation. Resection of parathyroid glands

This is only clinically relevant if the patient has had bilateral dissection, either simultaneously or metachronously. It is not advisable to divide the inferior thyroid artery lateral to the TE groove, as the parathyroids are supplied by this artery. It is better to divide the terminal branches distal to the glands. Damage to other structures

When dissecting a large multinodular gland, the pleura, oesophagus and membranous trachea are all at risk. A capsular dissection in these areas is necessary.

Early

Airway obstruction-this may be due to haematoma, bilateral recurrent laryngeal nerve palsy, tracheomalacia or laryngospasm from hypocalcaemia. Late

1 Unrecognised hypothyroidism.

2 Hypercalcaemia from vitamin D intoxication. 3 Recurrence of pathology.

Management of bypocalcaem~a It is the author’spolicy not to treat hypocalcaemia in the early phase until it is symptomatic.Whensymptoms occur(paraesthesiae, twitching, positive Trousseau’s and Chvostek’s signs), then 30ml of calcium gluconate in 300ml of dextrose saline is administeredintravenously slowly over 3 h. Blood is taken immediately before the infusion to check the calcium statusand

possibly to alter the amount of calcium that is given, althoughthe result will not be available untilafter starting the infusion. Caution must be exercised with patients on digoxin, who should be monitoredwith telemetry in an intensive-care setting. If thepatient again becomes symptomaticinthe first few days, furtherintravenous calcium gluconate is given, and also calcium Sandoz is commenced at 3g orally per day. Vitamin D supplements are usually also required promote to gastrointestinal calcium absorption. Calcitriol(la,25-dihydroxyvitaminD3)is started at1pg twice daily. Blood tests are usually required 12-hourly while the dose of calcitriol is adjusted. When theserum calcium reaches about the middle of the normal range, the daily dose of calcitriol is reduced by 0.5 pg increments, provided the calcium levels stay at the lower end of the normal range, to avoid hypercalcaemia. If hypercalcaemia occurs, calcium and calcitriol should be stopped and thepatient closely monitored to determine whether supplements arenecessary. After discharge, weekly blood levels of calcium, phosphate and creatinine are required until the condition stabilises. Ultimately the patient will continue to need blood tests at least 3-monthly.Measurement of urinary calcium is not necessary when using calcitriol. Despite its long half-life, thyroxine should be started immediately in the hypocalcaemic patient in order to avoid hypothyroidism, which impairs bone turnover.

There is considerable debateregardingtheextent of thyroid surgery for differentiated thyroid carcinomaand multinodular goitre. At issue are the reported rates of hypoparathyroidisminparticular,butalsorecurrentlaryngeal-nerve palsy, fortotalthyroidectomycompared with lesser procedures. After lobectomy, provided theopposite side has not been previously dissected, hypoparathyroidism does not occur and only one recurrent laryngeal nerve has been putat risk. For total thyroidectomy, rates of hypoparathyroidism are determined by the experience and skill of the individual surgeon. While experienced surgeons report incidences less than 2%, total thyroidectomy cannot be advocated for the occasional surgeon. Hypoparathyroidism is not simply managed but requires frequent monitoring and fine-tuning of medications. For differentiated thyroidcarcinoma,the choice of procedure is determined by the patient’s prognostic factors.The best prognosticindicators include the following: 1 age less than 40 years (male) or 45 years (female);

Tbyroid Surgery 2 tumour less size 4cm; than 3 follicular

carcinoma with minor capsular thyroidectomy

involvement; 4 extrathyroidal no extension; pears to 5 no systemic metastases. Poorer progostic indicators include the following: 1 age greater than 4.0 years (male) or 45 years (female); 2 tumour size greater than 4 cm; capsular with 3 follicular carcinoma major involvement; 4 extrathyroidal extension; 5 systemic metastases. There appears to be no difference in postoperative survival between lobectomy andtotal thyroidectomy in patients with good prognostic indicators. Proponentsof total thyroidectomy argue that recurrence is lower with the complete procedure. The author’s practice is to perform total thyroidectomy provided at least two parathyroids are identified and preserved. In the poorer prognostic group, recurrence is higher after less-than-total procedures. Also, most deaths from differentiated thyroidcarcinoma occur inthe first 5 years and from local recurrence. These patients are best served by removal of the whole gland. Total thyroidectomy facilitates postoperative radioiodine therapy-there is no delay while the residual lobe is being ablated-and the detection of systemic metastases

435

facilitated. A compromise between total and lobectomy is subtotal thyroidectomy (lobe plus isthmus plus most lobe), of other which apconfer the same local control advantage total as thyroidectomy, provided radioiodine given is postoperatively. Subtotal thyroidectomy has the advantage of posing less hazard to the parathyroid glands and usually puts only one nerve at risk.

is

Further reading Cohn KH, Backdahl M, Forsslund G et al. (1984) Biologic considerations and operative strategy in papillary thyroid carcinoma: argumentsagainsttheroutineperformance of total thyroidectomy. Surgery 96, 957-68. Harvey HK (1990) Diagnosis and management of the thyroid nodule: an overview. Otolaryngol. Clin. North Am. 23, 303-37. Sarnaan NA, Maheshwari YK, Nader S et al. (1983) Impact of therapy for differentiated Carcinoma of the thyroid: an analysis of 706 cases. J.Clin. Endocrinol. Metab. 56, 1131-8. Sarnaan NA, Schultz PN, Hickey RC etal. (1992) The results of various modalities of treatment of well differentiated thyroid carcinoma: a retrospective review of 1599 patients. J.Clin. Endocrinol. Metab. 75, 714-20. Shah JP, Loree TR, Dharker D, Strong EW, Begg C & Vlamis V (1992) Prognostic factors in differentiated carcinoma of the thyroid gland. Am. J.Surg. 164, 658. Shah JP, Loree TR, Dharker D & Strong EW (1993) Lobectomy versus total thyroidectomy for differentiated carcinoma of the thyroid: a matched-pair analysis. Am. J.Surg. 166, 331.

e Paroti

land

OHN C . WATKINSON

The following operationscan be performed on the parotid gland: 1 open biopsy; 2, superficial conservative parotidectomy; 3 total conservative parotidectomy; 4 total radical parotidectomy; 5 extended total parotidectomy; G in-continuity neck dissection. Each has its indications and contraindications and these are listed below.

vascular malformations and other miscellaneous swellings, such as lipomas. Most benign neoplasms are situated lateral to the facial nerve in the superficial part of the gland and, as such, are amenable to superficial conservative parotidectomy. Operationsto remove neoplasms fromthe cheek, mandible or infratemporal fossa, when facial-nerve preservation is mandatory, may also require a superficial parotidectomy as an integral part of the operation. Contraindications

Most parotid swellings will have had a fine-needle aspiration cytology (FNAC). In certain circumstances, when the diagnosis is unclear or the swelling is atypical, an open biopsy may be required. This shouldbe avoided, if possible, in all but the most difficult cases. When necessary, it should be done within 4weeks of, or as an entree to, the main procedure. The biopsy track should subsequently be excised.

The most common indications for superficial parotidectomy involve slowly growing and discrete intraparotid swellings which do not infiltrate the adjacentglandparenchyma. Most of these swellings are benign neoplasms, of which 80% include the pleomorphic adenoma and a small number of Warthin’s tumours. The remainder include small malignant neoplasms (4cm or less), cysts, intraparotid lymph nodes,

Any large malignant neoplasm (greater than 4 cm) should be removed (where possible) by total conservative parotidectomy. Recurrent pleomorphic adenomas, recurrent malignant neoplasms and congenital first-arch abnormalities are best dealt with by total conservative parotidectomy. Preoperative management

Special features of the history indicating malignancy include rapid swelling, pain and facial twitching. Examination should include the facial nerve and oral cavity, alongwithbothparotid and neck regions. Informed consent shouldbe offered regarding facial-nerve damage and excision and selective neck dissection. FNAC is usually indicated. CT and MRI are useful to assess large benign swellings, to distinguish between deep-lobe parotid swellings and parapharyngeal masses, and to stage malignant tumours regarding resectability and relationship to vital structures, as well as for radiotherapy planning.

Surgery of the Purotid Gland Surgical anatom

The key essential to conservative parotid surgery is total preservation of the facial nerve and its branches, so that a detailed knowledge of its anatomy is mandatory. The commonest method of identification is to find the nerve just after it has emerged fromthe skull base at the stylomastoid foramen (Fig. 6 1.1). The following markers may be used: 1 Themost reliable is thetympanomastoid groove, formed by the anterior partof the mastoid and the edge of the bony external auditory meatus (EAM). The facial nerve bisects the apex of this groove 5mm below the bony meatal edge. It then passes forwards, downwards and laterally, where it is immediately above the upper border of the posterior belly of the digastric and lateral and slightly posterior to the base of the styloid process. 2 A less reliable method is the arrow-shaped configuration of the cartilaginous meatus (Conley's pointer). The nerve lies approximately 1cm deep and inferior to the tip of the pointer. 3 Branches of the nerve can be found peripherally and traced proximally. Usually themarginalmandibular branch is identified where it crosses the posterior facial vein at the tail of the gland, and it can then be traced proximally to the lower division. This, in the author's opinion, is labour-intensive and, where difficulty arises in nerve identification (suchas large malignant tu-

43';7

mours), the best*way tofind the facial nerve is by opening the mastoid. The greater auricular nerve lies on the deep cervical fascia, which invests the sternomastoid muscle and inclines upwardsto cross the superficial aspect of the parotidgland.Itcan be used (incollaborationwith other branches of the cervical plexus)for free cable grafts infacial-nerve reconstruction. The posteriorfacial vein traverses the deep lobe of the gland from above downwards, lying immediately medial to the branches of the facial nerve. The external carotid artery (ECA) lies deep to the vein and is not normally seen in a superficial parotidectomy. Both vessels are excised, however, ih operations to remove the gland in total. Operative tee

Preparation

1 Anaesthesia. Premedication is given at least 1h before the operation and is the choice of the anaesthetist. The operation is performed under general anaesthesia with spontaneous respiration and without using muscle relaxants, in order to facilitate stimulation of the facial nerve. Controlled hypotension is useful, since it reduces blood loss and allows quicker dissection of the nerve. Depending on the extent of the procedure, hair may be shaved behind the ear or from the top of the preauricular crease. 2 Prophylatic antibiotics are not usually necessary. 3 Position of patient. The patient is placed in the supine position with a sandbag placed under the shoulders to slightly extend the neck and the head is turned away from the surgeon. The table is elevated to 15" toreduce venous congestion and arterial pressure. The homolateral eye and corner of mouth are left visible, being covered with a plastic drape. 4 If a nerve monitor such as the Magstim is to be used, the electrodes should be positioned at this point. Incision

Fig. 61.1 The surgical anatomy of the facial nerve.

This commences superiorly in front of the ear in the preauricular crease. At the lower border of the ear, it curves under the lobule of the ear to gain access to the lower border of themastoid process, andthen runs downwards and forwards on the sternomastoid muscle to finish inferiorly in the neck, using a skin crease 2cm below the lower border of the mandible (Fig. 61.2). The incision is made down on to the parotid fascia and through the platysma in the neck down to the level of, but not through, the deep cervical fascia.

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Chapter 61

Fig. 61.2 The incision for parotidectomy.

The deep investing cervical fascia is divided where it blends with the parotid fascia on the anterior border of sternomastoid. Superiorly, the gland is separated from themastoid process and thecartilaginousmeatus by blunt dissection (Fig. 6 1.4). 3 The sulcus that now exists is deepened to expose the posterior belly of the digastric, which is thentraced upwards. With an assistant pulling the parotid gland forwards and upwards, an attempt is made to identify the main trunk of the facial nerve. 4 Using the landmarks mentioned above, a haemostat is used to spread the fibrous tissue to search for the nerve in the groove formed by the bony meatus and the mastoid process. If there is any doubt, any structure should be stimulated, using the nerve stimulator. This is undoubtedly helpful butshould not replace sound anatomical knowledge, since this techniquecan fail to stimulatethe nerve or can excite itfroma distance. From this point onwards, bipolar diathermy should be used (Fig. 61.5). 5 Once the nerve has been confidently identified, the haemostat is inserted along the superficial axis of the

Fig. 61.3 The anterior flap, consisting of skin and subcutaneous tissue along with platysma inferiorly, is raised using the knife and retracted forwards. The plane of dissection is ‘under the platysma in the neck, over the platysma on the face’.

Procedure in stages 1. The anterior flap is raised, remembering to stay under the platysma in the neck and over the platysma on the face. The flap is held forward by silk stay suturesand the ear lobule retracted back by a similar thread (Fig. 61.3). 2 The greater auricular nerve is identified and divided.

Fig. 61.4 At this point, an attempt is made to find the main trunk of the facial nerve. The sulcus between the parotid gland and the external meatus and the mastoid process is deepened so that the edge of the bony meatus can be identified. The fibrous bands bridging the sulcus are quite dense and contain one or more veins which can cause troublesome bleeding. Using a mosquito haemostat to dissect these bands in the sulcus, the facial nerve is identified by blunt dissection in the tympanomastoid groove formed by the bony meatus and the mastoid process.

Surgery of theParotidGland

Fig. 61.5 The haemostat is inserted along the upper division of-the nerve, its blades opened and the haemostat lifted so that glandular tissue is then incised upwards and backwards with a knife or scissors to divide the posterior border of the gland. This process is then repeated using the haemostat, remembering the words ‘insert, lift, open and cut’.

Fig. 61.6 Using the same technique along the inferior division of the nerve, the lower half of the posterior border and the inferior border of the gland can be freed to allow the superficial lobe to be pedicled anteriorly.

439

main nerve trunk to establish a plane and to identify the bifurcation. Depending on the site of the tumour, dissection can now begin in either a superior or an inferior direction. The haemostat is slid over the upper (or lower) division and the blades opened. 6 The instrument is then raised and glandular tissue incised with a no.15 blade by cutting on tothe posterior blade of the haemostat. This technique -insert, spread, lift, cut -is then repeated to excise the superficial lobe by including the tumour with a normal cuff of parotid tissue and preserving the branches of the facial nerve. The superficial lobe is usually pedicled anteriorly but may be pedicled either inferiorly or superiorly, depending on the site of the tumour (Fig. 61.6). ’7 Dissection may be facilitated by the use of an operating microscope or loupes. Small bleeding vessels should be tied off with fine catgut or Vicryl. If the parotid duct is identified, it can be divided and ligated. At the end of the procedure, the facial nerve must be

Fig. 61.7 The buccal branches are traced forwards and the pedicle of the superficial lobe is eventually cut. Often the retromandibular vein (which lies vertically deep to the branch of the facial nerve) is seen at this point as it emerges from the tail of the remaining gland just posterior to the mandibular branch of the nerve. At this point in the dissection, the parotid duct is often encountered and may be ligated. In the process of following the mandibular branch of the nerve forwards and downwards, the lower limit of platysma can now be divided. It is important not to undermine platysma too much early in the dissection, as the mandibular branch may well be inadvertently cut as this stage.

tionaryand,as such, requires re-exploration of the wound and the appropriate vessels to be ligated. aematoma

This can occur due to the large dead space. It is usually prevented by the use of suction drainage and a pressure bandage. Small haematomasare best left alonebut larger ones require evacuation. Anaesthesia and facial weakness

Fig. 61.8 The wound is closed in two layers and the suction drainage is inserted. Platysma is closed with an absorbable stitch and the skin closed with either interrupted nylon or clips.

stimulated to confirm that the nerve is in continuity(Fig. 61.7). 8 When dealing withhaemangiomas and lymphangiomas, the technique should be modified. These tumours often infiltrate surrounding structures (particularly skin), so the anterior skin flap should be made as thin as possible.

At the end of the operation, the wound is closed in two layers. The platysma is closed by inserting an absorbable suture and the wound is drained with a vacuum drain brought out posteriorly nearthe hairline to hide the scar. The skin is closed with clips or interrupted Ethilon and the woundmay be covered with a pressure bandage for 24h (Fig. 61.8).

Division of the greater auricular nerve results in anaesthesia of the preauricular region and the lower half of thepinna.This usually settles in time asthepatient accommodates to the deficiency but can occasionally be lessened by attempting to preserve the posterior branches of the nerve. In routine superficial parotidectomy, the incidence of facial-nerve weakness is usually low (less then 15%) and the weakness is most often temporary. Resolutionis the norm as long as nerve continuity is maintained. Fistula formation

This is fortunately rare and is probably due to excessive saliva production in the remaining deep lobe. If the duct has not been ligated and production persists, then lowdosage radiotherapy is a therapeutic option.

Gustatory sweating on the side of the face at mealtimes can occur in up to 20% of patients. There is often a delay in onset of several months. Prevention is with the application of an antiperspirant. Occasionally tympanic neurectomy is worthwhile. Keloid scar

Occasionally this is aproblem; conventional manner. The pressure bandage is removed the next day, the drain can usually be removed after 48 h and stitches can usually be taken out at 5-7 days.

This is uncommon but when it occurs it is usually reac-

it is managed in the

This operationremoves the superficial and deep lobes of the parotid gland, with preservationof the facial nerve. It is indicated in benign neoplasms affecting the deep lobe, recurrent pleomorphic adenomas and large (greater than 4 cm) malignant tumours. It is also indicated in recurrent, severe parotid enlargement due to sialectasis, chronicsuppurativeparotitis secondary to

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poral artery and maxillary artery to allow the deep lobe to be removed from its bed. Occasionally the ECA lies deep to the deep lobe and can be spared (Fig. 61.10).

As for superficial parotidectomy except the incidence of temporary and permanent facial weakness is higher.

Fig. 61.9 By retracting the upper division of the facial nerve upwards and the lower division likewise downwards using a nerve hook, the deep lobe of the parotid gland may be dissected away from the posterior border of the ascending ramus of the mandible and from the temporomandibular joint.

This operation is most commonly performed for highgrade carcinomas of the parotid gland, which usually invade the facial nerve and cannot safely be removed without sacrificing it. It is sometimes performed in recurrent operations for pleomorphic adenomas and lowgrade carcinomas where, due to technical reasons, the nerve cannot be saved. Total radical parotidectomy is also an initial integral step when performing subtotal petrosectomy. The operation is contraindicated in lymphomas and for benign lesions which mimic carcinoma by enveloping the nerve. Sarcoidosis, tuberculosis, cat-scratch disease, HIV and benign lymphoepithelial lesions should also be excluded.

calculi or ductal stenosis and first-arch branchial abnormalities. Total conservative parotidectomy is contraindicated for neoplasms that grossly involve the facial nerve. Preoperative and anaesthesia

As for superficial parotidectomy. Operation

A superficial parotidectomy is performed and usually the superficial lobe is pedicled inferiorly between the cervical and mandibular branches of the facial nerve. Alternatively, the deep lobe may be removed as a separate specimen. The facial nerve is mobilised using fine scissors and is elevated witha nerve hook (Fig. 61.9). The deep lobe is mobilised from the styloid process, the ascending ramus of the mandible and the temporomandibular joint (TMJ) with either small scissors or a pledget. The ECA and posterior facial vein are ligated inferiorly; the upper end of the posterior facial vein is ligated superiorly along with the superficial tem-

Fig. 61.10 The external carotid artery is divided at the lower border of the gland above the posterior belly of digastric and stylohyoid muscles and superio& where it becomes the superficial temporal artery. The accompanying veins are also ligated.

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Chapter 61 Postoperative care

A tarsorrhaphy will probably be required if the whole nerve is sacrificed. In cases of complete facial paralysis, where nerve grafting is not performed or is unsuccessful, facial slings, pedicled muscle transposition or free muscle transfer may be required.

Extended radical parotidectomy

Fig. 61.11 The parotidectomy incision may be extended using a utility neck incision to facilitate a neck disection.

Preoperative preparation

The patient should be shaved as required and consent obtained to sacrifice the facial nerve. In all cases, a diagnosis of cancer must be obtained before the nerve is removed. This should be by previous biopsy (see earlier) or frozen section. Operation

The skin incision is as for superficial parotidectomy but withupwardextension in thetemporal hairline and lower extension in aneck crease, as required. An extension inferiorly may be necessary to carry out radical neck dissection (Fig. 6 1.11). A total parotidectomy is performed with sacrifice of the facial nerve. The nerve should only be removed whenmacroscopic invasion by tumour is confirmed. Access to the nerve to facilitate preservationcan be improved by mastoid exploration and/or neck dissection. Clearance of tumour within the nerve should be confirmed by frozen section in cases of adenoid cystic carcinoma.Thedistal branches of the facial nerve aremarkedwith silk, and primary cable grafting is performed using branches of the cervical plexus or the sural nerve. Freeze-thawed muscle is an acceptable alternative.

Radical parotidectomy may be extended to include contiguous structures such as the ascending ramus of the mandible (and occasionally the TMJ), the zygomatic arch, the temporalisand sternomastoid muscle (anterior part), as well as the lower part of the medial pterygoid muscle, the bony and cartilaginous meatus and the mastoid process. This operation is usually done in conjunction with a radical neck dissection. Skin may be involved and can be included when total conservative parotidectomy is carried out for recurrent benign and low grade malignant tumours. Most cases can be reconstructed by shaping the excision as an ellipse which follows the incision and then performing a mini-face-lift. Larger defects can be filled using pedicled myocutaneous flaps (pectoralismajor or latissimus dorsi) or free flap transfer.

Neck dissection Elective neck dissection for the NO neck may be indicated in high-grade mucoepidermoid and squamous-cell carcinoma(SCC),as well asadenocarcinomas of the parotidgland. In such cases all five levels should be dissected (in theory, a modified radical neck dissection type 3). However, since the operation is usually performedwithaparotidectomy(extended neck dissection), removal of thesternomastoid muscle actually facilitates identification of the facial nerve, so that speed and ease of operation often dictate that it is more convenient to carry out a modified radical neck dissection type 1. Thisoperationcanalso be performedwhen access isrequired for the reconstructionof defects which require pedicled myocutanous pectoralis major or latissimus dorsi flaps. With low-grade tumours, neck-node sampling can be carried out in level 1 with frozen-section control. Positive disease facilitates proceeding to neck dissection, as described above. Palpable nodes should be treated by extended modified or radical neck dissection.

"Stlrgeryof the ParotidGland

Further reading Kaplan MJ & Johns ME (1993) Malignant neoplasms of the salivary glands. In: Cummings CW, Fredrickson JM,Harker LA, Krause CJ & Schuller DE (eds) Otolaryngology -Head and Neck Surgery,Vol. 2, 2nd edn. St. Louis, Mosby Year Book.

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Suen JY & Snyderman N L (1993) Benign neoplasms of the salivary glands. In: Cummings CW, Fredrickson JM, Harker LA, Krause CJ & Schuller DE (eds) Otolaryngology-Head and Neck Surgery, Vol. 2 , 2nd edn. St. Louis, Mosby Year Book.

A N D R E W C. U R Q U H A R T

Because of the recent modifications of various neck dissections, as well as the often somewhat confusing terminology to describe them, the American Academy Committee for Head and Neck Surgery and Oncology adoptedthe following classification (Robbins et al., 1991): 1 radical neck dissection; 2 modified radical neck dissection; 3 selective neck dissection; 4 extended radical neck dissection. A radicalneckdissection consists of removal of all lymph-nodegroups (levels 1-5) and all threenonlymphatic structures (spinal accessory nerve, sternocleidomastoid muscle and IJV). A modified radical neck dissectionconsists of removal of all lymph-node groups (levels 1-5) with preservation of one or morenon-lymphaticstructures. A type 1 modified radical neck dissection preserves thespinal accessory nerve, a type 2thespinal accessory nerve and the IJV and a type 3 the spinal accessory nerve, the IJV and thesternocleidomastoid muscle. The type 3 modified radical neck dissection describes the functional neck dissection. Selectiveneckdissections consist of preservation of oneor morelymph-nodegroups and all threenonlymphaticstructures.Therearefour different named types depending on the lymph-node groups removed: supraomohyoid (levels l-3), posterolateral (levels 2-5, postauricular and suboccipital nodes), lateral (levels 24) and anterior (level 6). An extendedradicalneckdissection consists of removal of all of the structures resected in a radical neck dissection andoneor moreadditionallymph-node groups or non-lymphatic structures or both.

Local control of cancer of the head and neck has improved over the lastfew decades, partly dueto appropriatemanagement of the neck. Cervical metastasis is associated with apoor prognosis (Spiro et al., 197’4)and extracapsular spread is an even stronger indicator of a very poor prognosis (Johnson et al., 1981,1985). Extracapsular spread is diagnosed histologically by the neck dissection specimen being meticulously examined by a pathologist. The Sloan Kettering Memorialgroup(Shah et al., 1981) described six levels of cervical lymph nodes routinely removed in neck dissection procedures (Fig. 62.1). Level 1 Submental and submandibular group of nodes Level 2 Upper deep cervical group of lymph nodes around the internal jugular vein (IJV). Boundaries extend from the skull base to the carotid bifurcation (surgical landmark)or hyoid bone (clinical landmark) Level 3 Lymph nodes around the middle third of the cervical part of the IJV. Boundaries extend from the carotid bifurcation superiorly to the omohyoid muscle (surgical landmark)or cricothyroid notch (clinical landmark) inferiorly Level 4 Lymph nodes around the lower third of the cervical part of the IJV extendingfromthe omohyoid muscle to the clavicle Level 5 Lymph nodes in the posterior triangle, located along the lower half of the spinal accessory nerve and the transverse cervical artery Level 6 Lymph nodes of theanteriorcompartment, located around the midline visceral structures of the neck 444

RadicalandConservativeNeckDissections

445

squamous-cell carcinoma (SCC) of upper the aerodigestive tract. 2 Carcinoma of the thyroid gland with palpable lymph nodes in the lateral compartment of the neck.

1 SCC of the oral cavity (T2 to T4) with no palpable lymph nodes. 2 Single, palpable, mobile node in level 1or 2 from SCC of the oral cavity, lip or skin of the midportion of the face. 3 Together with parotidectomy in patients with Merkel-cell carcinoma and certainmelanomas of the cheek and zygomatic region.

Fig. 62.1 Levels of cervical lymph nodes.

The surgical treatment of the neck may include any of the above neck dissections. In the past, a radical neck dissection was done in the presence of cervical metastasis, with a wait-and-see policy regarding the uninvolved neck. It is apparent now that the information provided through the pathological assessment of the neck dissection specimen may provide valuable information regarding patient counselling, therapeutic decision-making and comparison of end results.

1 Cervical metastasis with lymph nodes in the posterior triangle of the neck and closely related to the spinal accessory nerve. 2 Large tumour mass or multiple nodes in the upper neck.

1 Patients with cervical metastasis where the spinal accessory nerve is not involved by turnour and preservation will not result in a risk of entering tumour. 2 Elective treatment of the NO neck, although there is some questionwhether such an extensive procedure needs to be done in these situations.

1 NO neck for elective treatment in patientswith

1 Carcinoma of the larynx, oropharynx and hypopharynx staged T2 to T4NO. 2 Carcinoma of the larynx, oropharynx and hypophyarynx staged T1 N 1 when a palpable nodeis in level 1 or 2. For both of the above, bilateral neck dissections are usually performed, because of the high incidence of bilateral metastask.

Skin tumours such as melanoma, SCC and Merkel-cell Carcinoma that originate in the posterior and posterolateral aspect of the neck and occipital scalp.

1 Transglottic and subglottic carcinoma, carcinoma of the cervical oesophagus and thyroid Carcinoma: remove paratracheal and pretracheal nodes. 2 Neck dissection may be extended to remove the retropharyngeal nodes when the primary tumour originates in the pharyngeal wall. 3 Involvement of non-lymphatic structures such as the hypoglossal nerve, levator scapulae muscles or carotid artery.

Assuming that the primary site of metastasis has been identified, the next important issue is one’s ability to predict disease in the neck. The physical examination, various imaging modalities and the histological findings are all important in this regard. As we know, certain

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primary sites will have a higher incidence of cervical metastasis and the location of the primary tumour can often predict which group of lymph nodes will be involved. Bilateral metastasis is also morecommonin certain sites. In carcinoma of the supraglottic larynx for example, we would expect bilateral cervical metastasis to the deep cervical lymph nodes (level 2 , 3 and 4) with very little chance of involvement of the submental and submandibular group of nodes (level 1). There are many factors that may affect the correlation between the clinical and pathological findings of necknode metastasis. The experience of the examiner is important, but diagnostic means that improve the detection rate have been sought. CT scanning has been available as a diagnostic tool for over a decade. Most reports support a high correlation of 80-95% between CT scan and pathological findings (Stevens et al., 1985; Close et al., 1989). Although MRI provides soft-tissue contrast equal to or better than CT, MRI is unable to visualise necrosis within a node aswell as CT. It does, however, appear to be as sensitive as CT in identifying cervical lymph-node metastasis (Friedman et al., 1990). Balloon test occlusion and CT xenon flow studies are donein some institutions, usually if there is tumour involving the carotid vessels.

anterior border of the sternocleidomastoid muscle, the midline of the neck and the inferior border of the horizontalramus of themandible.Theposterior cervical triangle is formed by thesternocleidomastoid muscle anteriorly, theclavicle caudally and the trapeziusmuscle posteriorly. The base of the triangle is formed by the clavicle and the apex is located at the mastoid tip. The anterior cervical triangle is divided by the digastric and omohyoid muscles into the submandibular, submental,carotid and muscular triangles. The posterior cervical triangle is divided by the inferior belly of the omohyoid muscle into the occipital and subclavian triangles. The large occipital triangle is formed by the sternocleidomastoid muscle in front, the trapeziusmuscle behind and the omohyoid muscle below. The floor is formed by the splenius capitus,levatorscapulae and medial and posterior scalene muscles. The subclavian triangle is formed by the omohyoid muscle above, the clavicle below andthesternocleidomastoid muscle anteriorly. Within the triangle are the brachial plexus, subclavian vein and artery and branches of the thyrocervical trunk. The platysma muscle extends from the lower border of the mandible above, across theclavicle to the level of the first and second rib. Theexternal jugular vein descends down vertically from behind the angle of the mandible, acrossthe sternocleinomastoid muscle to its posterior border, and pierces the investing deep cervical fascia 2cm above the The neck is divided into the anterior and posterior trian- clavicle. The IJV lies lateral to the carotid artery within gles (Fig. 62.2). The anterior triangle is formed by the the carotid sheath. At the level of the hyoid bone it is

1

Fig. 62.2 Triangles of the neck.

~ a d i c aand l ConservativeNeckDissections

I

Descendens hypoglossi nerve

\carotid artery

Fig. 62.3 Spinal accessory and hypoglossal nerves in the upper neck.

joined by the common facial vein, and the middle thyroid vein flows into it slightly lower down. The carotid artery lies medial to the IJV and atthe level of the hyoid bone forms the carotidbulb and divides into the internal (ICA) and external carotid artery (ECA). The spinal accessory nerve is the most posterior of the three nerves leaving the jugular foramen (Fig. 62.3). At first it lies between the IJV and ICA and then it crosses to the lateral surface of the IJV as it continues to descend obliquely to theupperborder of the sternocleidomastoid muscle, approximately 4 cm below the tip of the mastoid. At this point cutaneous nerves from the cervical plexus (C2, C3 and C4) radiate from the posterior border of the sternocleidomastoid muscle just below the spinal accessory nerve. The nerve passes throughthesternocleidomastoid muscle and travels across the posterior triangle between the superficial and pre-vertebral layers of cervical fascia. The nerve is joined by a branch of C2 before entering the deep surface of the sternocleidomastoid muscle and by branches of C3 and C4 before entering the trapezius muscle. The hypoglossal nerve emerges between the IJV and ICA, covered by theposterior belly of the digastric muscle. It passes forward across the lateral surface of both the ICA and ECA at the level of the carotid bulb and givesoff the descendens hypoglossi (the superior root of the ansa cervicalis). The vagus nerve at first lies medial to boththe IJV and ICA. As it descends, it comes to lie behind and between

447

the carotid artery and IJV within the carotid sheath. The phrenicnerve arises from thecervical roots of C3, C4 and C5. It passes down in the neck with a slight medial inclination on the front of the anterior scalene muscle. It is covered by the prevertebral fascia. The brachial plexus appears between the anterior and medial scalene muscles and is covered by the prevertebral fascia. At the base of the neck is the termination of the large lymphatic ducts. On the left, the thoracic ductmay loop high into the neck and then open into the internaljugular vein, the subclavian vein or the angle of the junction between the two. The right lymphatic duct is formed by three channels, which usually emptyseparately or in variouscombinationsintothe angle between the IJV and subclavian vein or separately into either of these veins. The deep cervical fascia of the neck has three layers. The superficial (investing) layer of deep cervical fascia arises from the vertebral spinous processes and ligamentum nuchae and surrounds the entire neck. It divides to enclose thetrapezius muscle, butformsa single layer as it crosses the floor of the posterior triangle. Once again, it divides and surrounds the inferior belly of the omohyoid and sternocleidomastoid muscles. The middle (visceral) layer of deep cervical fascia is found in the anterioraspect of the neck, surrounding the visceral structures.The deep (pre-vertebral) layer of deep cervical fascia covers thevertebral muscles and extends laterally on the anterior andmedial scalene and levator scapulaemuscles, forming thefascial floor of the posterior triangle. Thecarotidsheath is formed by a fusion of all three layers of fascia.

Neck dissections are usually performed in conjuction with the resection. of a primary tumour but may also be done ontheir own. General anaesthesia is obtained, and it is important not to use long-acting muscle relaxants, particulary inneck dissections requiring identification of the spinal accessory nerve. Clean procedures are associated with a postoperative wound-infectionrate of less than 2% and antibiotic prophylaxishas little effect on reducing thatrate (Johnson & Wagner, 1987). Prophylactic antibiotics are not necessary if an isolated neck dissection is done; however, if the neck dissection is performed in conjunction with a primary resection involving the upper aerodigestive tract, prophylactic antibiotics should always be used. Antibiotics aremost effective whenadministration is priorto bacterial contamination (Burke,

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Chapter 62

Fig. 62.4 Positioning for routine neck dissection.

1961). The spectrum of coverage should include oral microflora, especially anaerobic bacteria. Coverage against Gram-negative aerobic bacteria is probably unnecessary. Antibiotics should be given 1h preoperatively before any incisions are made (Johnson & Yu, 1988).Most studies wouldsupportthree doses postoperatively, with no benefit obtained from longer coverage. High doses of cefazolin or clindamycin or a metronidazole-containing combination could be used. The positioningof the patient is important as thiswill often help withexposure of theoperative field (Fig. 62.4). The patient is placed in the supine position with

Fig. 62.5 Neck dissection incisions. (a) Latyschevsky and Freund. (b)Freund. (c) T-shaped.

a shoulder roll inserted under the neck and shoulder. The head is turned away and extended from the side being operated upon. The head and neck region is then cleaned and draped in the usual way. The incision described by Latyschevsky and Freund (1960)extends from the mastoid tip to the mandibleand is ideal for a neck dissection combined with an intraoral procedure (Fig. 62.5). A vertical limb can be extended down to the midportionof the clavicle, ensuring that the trifurcation is behind the sternocleidomastoid muscle. Whena neck dissection is combinedwitha laryngectomy, the apron incision described by Freund (1967)is ideal. For an isolated neck dissection, a T-shaped incision gives adequate exposure. Theincision extends from the mastoid tip, two fingers’-breadths below the mandible in a natural skin crease, up to the midline, with a vertical limb extendingdown to the midclavicular point. Once again, the trifurcation should be over the sternocleidomastoid muscle.

1 Using the scalpel, the incisions are made through the skin and platysma, takingcare to avoid theexternal jugular veins just deep to this on the surface of the sternocleidomastoid muscles. Lahey clamps are placed through the subcutaneoustissue and the skin is retracted perpendicular to the plane of dissection. With steady traction and sharp dissection, using either a scalpel or Bovie, the flaps are elevated in an avascular plane. 2 The common facial vein is identified and ligated and, while a long suture is maintained on the proximal end,

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the mastoid tip (Fig. 62.7’). Dissection continues down to the ‘sfilkiiius capitus and levator scapulae muscles, which form the floor of the dissection. The trapezius muscle is easily identified here and forms the posterior limit of the dissection. Using sharp dissection, the contents of the upper aspect of the posterior triangle are dissected towards the carotid sheath. At this stage the spinal accessory nerve is identified as it enters thelower third of the trapezius muscle. 4 Attention is now focused on the inferior aspect of the dissection. Using a scalpel or Bovie, the sternal and clavicular heads of thesternocleidomastoid muscle arecuthorizontally just above their insertions. The omohyoid muscle comes into view running across the field, just lateral to the carotid sheath, which is positively identified. The muscle is clamped and ligated at the level of the tendon and long a tie is kept on the upper end for retraction to be used later. 5 Next a superficial horizontal incision is made with a scalpel throughthe superficial layer of deep cervical fascia at a point just above the clavicle, lateral to the

Fig. 62.6 Removing the submandibular gland.

which is keptundertraction,the capsule of the submandibular gland is incised. This is reflected superiorly, with the marginal branch of the facial nerve being protected by the proximal stump of the common facial vein. The glandis then grasped with an Allis forceps and retracted inferiorly. The tissue between the inferior border of the mandible and submandibular gland is incised, exposing the mylohyoid muscle. Using a scalpel, the fibrofatty tissue is dissected off the anterior belly of the digastric and mylohyoid muscle. The posterior borderof the mylohyoid muscle is then well defined and retracted anteriorly by the assistant, while the surgeon maintains inferior retraction on thegland (Fig. 62.6). The first structure to be seen is the lingual nerve withthe submandibular ganglion. The inferior aspect of the ganglion is clamped and ligated. The submandibular duct, which is slightly deeper and runs in a parallel direction, is clamped and ligated. The hypoglossal nerve lies deeper and is identified but not disturbed. The facial artery is identified as it crosses under the posterior belly of the digastric muscle. It is clamped and carefully ligated, with the addition of a transfixion suture. 3 Using sharp dissection, the sternocleidomastoid muscle isthen incised horizontally, just below its insertion to

Fig. 62.7 Incision of sternocleidomastoid muscle just below its insertion to the mastoid tip.

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Fig. 62.8 Tunnel along floor of posterior triangle.

carotid sheath. While holding a gauze swab in either hand, the fascia is swept upwards. The brachial plexus and phrenic nerve, running from lateral to medial and protected by the deep (pre-vertebral) layer of deep cervical fascia, are positively identified. The transverse cervicalarteryrunningacrossthe base of theposterior triangle is often seen, and it is usually possible to avoid transecting this by sweeping it to the inferior aspect of the dissection. A tunnel is now created, using a finger, along the floor of the posterior triangle, above the deep (pre-vertebral) layer of deep cervical fascia towards the pointwherethespinal accessory nerve entersthe trapezius muscle (Fig. 62.8). Two curved artery forceps are placed on either side of the finger with the points exiting just below the spinal accessory nerve. The intervening fibrofatty tissue is cut, using a small scalpel blade. The tissue is oversewn, using a continuous suture, before releasing the clamps. The spinal accessory nerve is now transected and the entire contents of the posterior triangle are swept towards the carotid sheath, using sharp dissection. The roots of the cervical plexus are now identified, clamped and ligated, taking care to be abovethecontribution of the cervical plexus to the phrenic nerve. At this stage, the IJV should be identified from behind. G The IJV is now identified inferiorly and, while carefully grasping it with a Debakey forceps, the sheath is incised, using dissecting scissors. The carotid artery and vagus nerve are identified deep to the vein. While grasping the vein wall withthe Debakey forceps, arightangled forceps is inserted around the vein and, with the tip clearly showing, opened to grasp two silk sutures, whichare securely tied. Enough space should be left

between the ties for a transfixion sutureto be placed on either side before cuttingthe vein. This is best done using a scalpel and cutting on to the back of the flat surface of a forceps supporting the vein. At this point there is somefibrofatty tissue lateral to the inferior stump of the IJV and this is clamped and ligated in case it contains any of the large lymphatic ducts. 7 The specimen is now retracted superiorly and sharply dissected off the carotid artery. The middle thyroid and common facial veins are identified and ligated. The IJV is identified superiorly, deep to the posterior belly of the digastric muscle. It is cut and ligated in the same way as the inferior part of the vein. 8 The IJV, with the neck specimen, is now dissected off thecarotidartery.The hypoglossal nerve should be identified and preserved as it crosses the carotid artery on its way to the tongue (Fig. 62.3). The final part of the dissection is carried out with traction applied to the stump of omohyoid muscle, which is dissected up to and off the hyoid bone. 9 Thewound is irrigatedwithnormal saline and haemostasis is meticulously obtained. Two small suction drains are inserted and brought out of the inferior aspect of the wound. They are sutured in position and immediately connected to suction while the skin closure is completed (to prevent clottingwithinthetubing). Closure is undertaken in two layers; the platysma and subcutaneous tissue are closed with interrupted Vicryl sutures and the skin is closed with staples. There must be an airtight closure and any air leaks should be carefully sought. Bacitracin ointment is placed alongthe incisions and this is covered with thin Telfa strips. A dressing consisting of fluffed-out gauze sponges with a wrap around the neck is applied. Modified radical isseetion (type

I)

Steps 1 and 2 are exactly the same as for a radical neck dissection. When the spinal accessory nerve is identified entering the lower third of the trapezius muscle, it is carefully traced forward through the posterior triangle of the neck towardsthesternocleidomastoid muscle (Fig. 62.9). Using a Debakey forceps on either side of the nerve, with good assistance, the tissue is carefully dissected off the nerve, using small dissecting scissors. A s it enters the sternocleidomastoidmuscle, a small forceps is placed just above it and gently spread open, and the intervening muscle is cut. This continues up to the level of theposterior belly of the digastric muscle, where the nerve is noted to be lying just lateral to the IJV. A vessel loop -is now placed around the nerve, which should be completely free of soft-tissue attachments.

Radical and Conservative Neck Dissections

Fig. 62.9 The spinal accessory nerve is traced forward from the posterior triangle.

At this stage, the sternocleidomastoid muscle is incised horizontally, below its insertion to the mastoid tip. Care should be taken not to injure the spinal accessory nerve in its exposedpaththroughthesternocleidomastoid muscle. Using sharp dissection, the contentsof the upper aspect of the posterior triangle and sternocleidomastoid muscle are reflected below the nerve, which is retracted out of the wayby the assistant. Therest of the procedure is exactly the same asforaradical neck dissection, except that care is taken to preserve the integrity of thespinal accessory nerve whenapproaching it fromthe inferior aspect of the neck dissection and reflecting thecontentsforward onto thecarotid sheath.

This is the well-described functional neck dissection withpreservation of the IJV, spinal accessory nerve and sternocleidomastoid muscle. Onceagain, steps 1

45 I

and 2, arethe same asforaradical neck dissection. 3 The fascia is then dissected off the sternocleidomastoid muscle, using sharp dissection, from the posterior to the anterior border. The greater auricular nerve and external jugular vein can usually be preserved. The fascia is grasped and reflected forward.The sternocleidomastoid muscle is retracted towards the surgeon and the fascia is sharply dissected off the medial surface of the muscle. Thespinal accessory nerve is identified entering the muscle on the deep medial surface, at the junction between the upper third and lower two-thirds. Now, grasping the fibrofatty tissue on either side of the nerve with a Debakey forceps, it is dissected forward, using small dissecting scissors. A vessel loop can be applied around thenerve for traction, and dissectioncontinuesforward to theposterior belly of the digastric muscle, where it lies lateral to theinternal jugular vein. The nerve is completely freed and retracted inferiorly with the vessel loop, and the sternocleidomastoid muscle is retracted towards the surgeon. 4 The fibrofatty tissue is now cut at the apex of the posterior triangle, using a small scalpel blade. This is best performed by cutting directly down on tothe floor of theposterior triangle, withthe nerve retracted inferiorly out of the way. Troublesome bleeding can be noted in this area, but time is well spent in keeping the operative field dry. The muscles at the apex of the posterior triangle must be seen. The spinal accessory nerve is then retracted superiorly with the vessel loop, and the fibrofatty tissue of the apex is grasped from below with an Allis forceps and reflected beneaththe nerve (Fig. 62.10). 5 Using sharp dissection with a scalpel, the tissue is dissected off the cervical plexus. This is facilitated by using the left hand with swab a to sweep the tissue forwardand maintaintraction, while gently cutting down in a perpendicular plane to the cervical plexus (Fig. 62.1 1).At this stage the spinal accessory nerve is identified where it exitsfrom below the sternocleidomastoid muscle in theposterior triangle of the neck. It is freed of soft-tissue attachments, using a Debakey forceps and small dissecting scissors. 6 The fibrofatty tissue is now cut along the anterior border of thetrapezius muscle, using a scalpel. The tissue is reflected forward off the splenius, levator scapulae and scalenus medius muscles. 7 A horizontal incision is made through thesuperficial layer of deep cervical fascia, just abovethe clavicle. Theexternal jugular vein and omohyoid muscle are clamped and ligated. Using a sponge in one hand, the fibrofatty tissue is swept off the floor of the posterior

forms the inferior aspect of the dissection. Sharp dissection continues, staying superficial to the cervical plexus until the IJV comes into view from behind. The fascia is removed from the vein, using sharp dissection, and the entire specimen is then freed by following the omohyoid muscle up to its attachment to the hyoid bone.

Postoperatively, all neck dissections aretreated in a similar manner. Antibiotics are given for three postoperative doses and then discontinued. Ambulation is encouraged in the postoperative period as soon as possible. The drains are removed separately, when the total drainage in each is less than 15m1 over 24 h. This usually occurs on the third or fourthpostoperative day. The skin clips are removed on the tenth postoperative day, often when the patient returns for a postoperative visit.

Fig. 62.10 Fibrofatty contents at apex of posterior triangle reflected beneath spinal accessory nerve.

triangle. The brachial plexus and phrenic nerve are visualised. 8 The sternocleidomastoid muscle is retracted posteriorly and the contents are dissected forward towards the carotid sheath. It may be helpful to place Allis forceps along the edge of the tissue, which is gently held by an assistant at right angles to the field. 9 Continue with sharp dissection, staying superficial to the cervical plexus until theIJV comes into view from behind, and continue dissecting until it is completely freed of attached fascia (Fig. 62.12). 10 Theentire co-ntents are now reflected beyond the vein and the omohyoid muscle is used as a lever, with dissection continuing up to the hyoid bone.

A selective neck dissection with removal of lymphatic tissue from levels 1, 2 and 3 will be described. The dissection is exactly as described for a modified radical neck dissection (type 3) upto the dissection of the fibrofatty tissue off the cervical plexus, after the spinal accessory nerve has been isolated and mobilised in level 2. At this stage, dissection continues down in front to the omohyoid muscle, which is transected and ligated, keeping alongsuture on theproximalstump.This

This problem usually occurs within the first 24 h. Apart from good surgical technique with adequate haemostasis, care should be given to the drains. These should be attached to suction as soon as they are inserted into the wound in order to prevent clot formation. Continuous wall suction in the recovery room and ward will also prevent inadvertent loss of vacuum. All haematomas should be evacuated and the wound copiously irrigated.

Fig. 62.11 Dissecting tissue off cervical tissue,

Radical and Conservative Neck Dissections

45 3

This is by far the most dangerous and potentially lethal complicationthatcanoccur. Skin incisions shouldbe planned so as to avoidtrifurcations over thecarotid artery. Meticulous closure of oral and pharyngealdefects is imperative to stop contamination of the wound with saliva. A sentinel bleed may signalimpending rupture andprompt surgicalinterventionshould be attempted.

Fig. 62.12 Contents of neck dissection are reflected up towards the hyoid bone.

This is usually noted as an increased drainage o f clear fluid in theneckdrains in thepostoperative period. Once feeding occurs, the fluid becomes milky in colour. Althougha chylous fistula mayclosespontaneously, surgical intervention is usually required, as a significant amount of protein may be lost.

Antibiotic use in contaminatedcasesappears to have resulted in a significant decrease in infections. Isolated neck dissections do not require antibiotic coverage, as these are clean cases. Most infections appearto occur as aresult o f continualcontamination o f the tissues by saliva (Newman et al., 1983). Appropriateantibiotic treatment and drainage are required.

Burke JF (1961)The effective period of preventive antibiotic action in experimental incisions and dermal lesions. Surgery 50, 161-8. Close LG, Merkel M, Vuitch MF, Reisch J & Schaefer SD (1989) Computed tomographic evaluationof regional lymph node involvement in cancer of the oral cavity and oropharynx. Head Neck 11, 309-17. Freund HR (1967) The Principles of Head and Neck Surgery. New York, Appleton-Century-Crofts. Friedman M, Mafee MF, Pacella BL, Strorigl TL, Dew LL & Toriumi DM(1990) Rationale for elective neck dissection in 1990. Laryngoscope 100, 54-9. Johnson JT& Wagner RL (1987) Infection following uncontaminated head and neck surgery. Arch. Otolaryngol. 113, 368-9. Johnson JT & Yu VL (1988) Antibiotic use during major head and neck surgery. Ann. Surg. 207, 108-11. Johnson JT, Barnes EL, Myers EN, Schramm VL, Borochovitz D & Sigler BA (1981) The extracapsular spread of tumors in cervical node metastasis. Arch. Otolaryngol. 107, 725-9. JohnsonJT, Myers EN, Bedetti CD, Barnes EL, Schramm VL & Thearle PB (1985) Cervical lymph node metastasis: incidence and implications of extracapsular carcinoma. Arch. Otolaryngol. 11 1, 534-7. Latyschevsky A & Freund HR (1960) Long upper flap incision for radical neck dissection. Surgery 47, 206-9. Newman RK, Weiland FL, Johnson JT, Rosen PR & Gumerrnan LW (1983) Salivary scan after major ablative head and neck surgery with prediction of postoperative fistulization. Ann. OtoE.RhinoE. Laryngol. 92, 366-8. Robbins KT, Medina JE, Wolfe GT, Levine PA, Sessions RB & Pruet CW (1991 ) Standardizing neck dissection terminology. Arch. Otolaryngol. 117, 601-5. Shah JP, Stiang E, Spiro PH & Vikiam B (1981) Neck dissection: current status and future possibilities. Clin. Bull. 11, 25-33, Spiro RH, Alfonso AE, Farr H W & Strong EW (1974) Cervical node metastasis fromepidermoidcarcinoma of the oral cavity and oropharynx Am. J.Surg. 128, 562-7. Stevens MH, Harnsberger HR, Mancuso AA, Davis RK, Johnson LP & Parkin JL (1985) Computedtomography of cervical lymph nodes: staging and management of head and neck cancer. Arch. Otolaryngol. 111, 735-9.

KEITH J. DAVI

Introductio

mours allows the surgeon to formulate an appropriate differential diagnosis, which is based on physical examination and imaging techniques.

Parapharyngeal-space tumours may arise fromthe contents or surrounding structures of the potential parapharyngeal space. It is estimated that parapharyngeal-spacetumoursaccountforapproximately 0.5% of head and neck tumours, 80% of which are benign and 20% malignant. Tumours of salivarygland origin account for approximately SO% of masses, originating from the deep lobe of the parotid gland or from salivary-gland rests. Those of neurogenic origin makeup an additional 30% (Heeneman & Maran, 1979; Bass, 1982; Heeneman et al., 1987; Davidge-Pitts et al., 1983).

Clinical presentation

Patientswithparapharyngeal-spacetumours usually have a late clinical presentation. Parapharyngeal-space masses allow fairly unrestricted anteriorand medial growth. A benign tumour becomes extremely large before it produces any form of symptomatology. Malignanttumours present earlier asa result of direct invasion of adjacent vital structures. The site of the mass is directly related to the origin of thetumour.Themostcommon presenting feature is anteromedial displacement of the palatine tonsil. Occasionally masses may present inferior to the parotid gland in the neck (Bass, 1982).

indications 1 To obtain pathological tissue for histological evaluation. 2 Resection of tumours for curative reasons. 3 Debulking of unresectable tumour mass in order to alleviate symptoms such as dysphagia and airway obstruction.

Imaging techniques

Imaging is essential in the evaluationof parapharyngealspace masses, and techniques include CT scanning, MRI and, where indicated, selective angiography (Fig. 63.1). MRI has replaced contrast CT scanning as a primary imaging modality for parapharyngeal-space masses (Cross et al., 1989). It has several advantages over CT scanning. MRI hassuperiorcontrastresolution,enabling better definition of the normal anatomical structures and establishment of tumour margins. Apart from offering an accurate assessment of the total extentof the mass,. the spatial relationship of the tumours to crucial vessels is also clearly shown. This important information enables the clinician to make a better and more

Contraindications C

1 Poor general medical health. 2 Extensive local infiltration by malignant tumours. 3 Metastatic disease. 4 Major vessel invasion.

Preoperative Evaluation

Evaluation of patientswithparapharyngeal-spacetu454

Surgery for Parapbary~geal-spaceTumours informed decision concerning the appropriate treatment plan. MRI doeshave some disadvantages. The main one is poor detection of calcification and of subtle bony changes produced by tumours. Thus there are clinical situations where both MRI and CT scanning are required in order to make a moredefinitive diagnosis or to include certain pathology in the differential diagnosis. CT scanning andMRI will divide the parapharyngealspace masses into enhancing (vascular) and nonenhancing (non-vascular) masses (Biller et aE., 198 la). All masses that are shown, on imaging, to be vascular are further evaluated with angiography. This will confirm tumour vascularity, and it demonstrates feeding vessels and the position of the carotid arteries.

Relevant anatomy The parapharyngeal space is a pyramidal-shaped potential space defined by fascial planes. It has as its base the skull and asits apex the hyoid bone. The medial boundary is formed by the pharyngobasilar fascia covering the superior constrictor muscle complex and tonsillar fossa. The lateral boundary includes the ramus of the mandible, fascia covering the deep lobe of the parotid gland and the medial pterygoid and digastric muscles (Fig. 632).The posterior boundaryincludes the pre-vertebral fascia and muscles, while the anterior boundaryincludes the pterygomandibular raphe. It is important to note

Fig. 63.1 Preoperative diagnosis of parapharyngeal-space tumours.

4 55

that the superior, lateral and posterior borders of the space are bdny and the only area for tumour expansion is anterior, medial and inferior. The parapharyngeal space is divided into a lateral and posterior retropharyngeal space by fascial planes (Fig. 63.3).Thelateral space is further divided intoa prestyloid and poststyloid space by the fascia enveloping the styloid process and its muscles extending anterior and medially to merge with the fascia surrounding the tensor veli palatini muscle. The prestyloid space contains the pterygoid muscles, ramus of the mandible,deep lobe of the parotid, internal maxillary artery, lingual, auriculotemporal and inferior dental nerves and lymph nodes. The poststyloid space containstheinternalcarotid artery (ICA), internal jugular vein (IJV), cranial nerves 9, 10, 11 and 12 and lymph nodes. The retropharyngeal space contains lymph nodes and fibrofatty tissue (Table 63.1). Some authors have further divided the prestyloid space to give a lateral masticator space. The only relevance of this space is thattumours arising in this area have direct access to the foramen ovale (Curtin, 1987’). Compartmentalisation is important because imaging techniques allow a more accurate preoperative diagnosis based on the anatomy of the parapharyngeal space.

allow access to the mouthwhile the posterior limit is the anterior border of the trapezius muscle.

There are three basic surgical approaches to the parapharyngeal space. This will depend on the type and extent of the parapharyngeal-space tumour. 1 Transcervical approach. 2 Transcervical approach with parotidectomy. 3 Transcervical approach withmidline mandibulotomy. In all cases the procedure begins with a transcervical approach. This may then be extended to the other two approaches if necessary. Transcervical approach

Fig. 63.2 Parapharyngeal space boundaries.

perative tec Preparatio Anaesthesia

Because of the inaccessibility and potential complications of operating in the parapharyngeal space, general anaesthesia provides a more controlled situation than local anaesthesia. The endotracheal tube (ET) should be passed transnasally on the side opposite that of the parapharyngeal-space mass. This keeps the mouth empty and facilitates intra-oral surgery. Prophylactic antibiotics

These are always utilised once the oral or pharyngeal mucosa has been opened. The importance of adequate anaerobic cover must be stressed. Patient position

The patient is placed in the supine position with the neck slightly extended and the head tuned away from the surgeon. The table may either be horizontal or inclined in ahead-upposition so as to reduce venous pressure in the head and neck region. The towels are arranged so that theentire face fromthe eye to the clavicle isexposed. The anteriorlimit of the towels must

1 The incision is located at the level of the hyoid bone. Itshould be carriedfromthe midline to theanterior border of Sternomastoid, where it curves superiorly on to the mastoid tip. It is important that the incision line is at least 2cm below the angle of the mandible, in order to avoid damaging the mandibular branch of the facial nerve (Fig*63.4). 2 The incision is continued through subcutaneoustissue and the platysma to the superficial layer of deep cervical fascia overlying the submandibular gland. Dissection is continued between the platysma and the superficial layer of deep cervical fascia, exposing the anterior belly, intermediate tendon and posterior belly of the digastric muscle. The anterior border of the sternomastoid muscle is also exposed. The common facial vein is identified in the region where the digastric muscle meets the sternomastoid muscle. At this point, the anterior facial veinis divided and ligated. The ligature on the distal segment of this vein remains long and is clamped for use retraction as a suture. The fascia overlying the submandibular gland is incised at the same level as the

Table 63.1 Compartment contents.

Surgery for Parapharyngeal-space Tumours

4 57

Fig. 63.3 Axia.l section of the

parapharyngea.l space.

skin incision. The anterior facial vein and the overlying superficial layer of deep cervical fascia are carefully elevated over the submandibular gland and,in so doing, the mandibular branch of the facial nerve is reflected superiorlyawayfromtheoperative field. The facial artery is identified superior to the posterior belly of the digastric and is divided and ligated. This enables the posterior aspect of the submandibular glandto be mobilised and thenretractedanteriorly and superiorly. In most instances, it is not necessary to remove the submandibular gland. 3 The tail of the parotid gland is now elevated. In order to accomplish this, it is necessary to divide and ligate the posterior facial vein. The parotid gland is freed from the adjacent sternomastoid muscle. The tail of the parotidis elevated to expose the posterior belly of the digastric muscle (Fig. 63.5). The carotid sheath is now exposed by retracting the sternomastoid muscle posteriorly. The common carotid artery and IJV should be adequately mobilised, using an angled Lahey together with Debakey forceps. Once these have been mobilised, they should be taped, thus providing vascular control prior to entering the parapharyngeal space. The hypoglossal and vagus nerves are also identified. At this stage, the ICA can be followed superiorly, deep to the mandible and styloid process. The posterior belly of the digastric muscle is divided and retracted posteriorly. This

manoeuvre opens the operativefield and exposes all the important structures leaving and entering the space. Themostimportantfactor in operating on the parapharyngeal space is extensive exposure of all the relevant cranial nerves and major vessels. Using the approach described above, the majority of tumours can be adequately exposed and removed. Transcervical approach with parotidectomy

Tumours in theparapharyngeal space involving the parotidglandrequirea superficial parotidectomy to expose and protect the facial nerve. 1 The incision is extended superiorly across the mastoid process to the point atwhich the lobe of the earjoins the face. It then follows the preauricular crease upwards to a point superior to the tragus (Fig. 63.4). 2 The anterior flap is elevated, using rakeretractors. Retraction is maintained in an outward anterior direction as the proper plane of dissection in the investing fascia of the gland is sought. The cleavage plane is best developed and carried anteriorly by scissor dissection. The anterior flap must only be mobilised to the periphery of the gland, so that the risk of damaging the distal branches of the facial nerve is minimised. 3 The superior cutaneous flap bearing the ear lobe is elevated next. After the dissection is carried up to the

458

Chapter 63 to permit identification of the great auricular nerve and external jugular vein. The anterior branch of the great auricular nerve is divided, as is the external jugular vein. It is important to ligate any vessels whose bleeding may interfere with clear visualisation of thetrunk of the facial nerve astheposterior surface of thegland is mobilised. 5 The facial-nerve trunk is identified in thenormal manner (Fig. 63.6). After the trunk has been isolated, the dissection is carried anteriorly in the plane of its branches. This will expose the facial-nerve complex and provide adequate visualisation for further dissection of the deep portion of the parotid gland.

Transcervical a ~ ~ r o awith c h medial mandibulotomy (Biller et al., 1981b)

A tracheostomy must be performed in all cases requiring a medial mandibulotomy.Thisapproach is primarily reserved for large or vascular parapharyngeal-space tumours, where maximum exposure of the skull base is required. This is necessary for control of bleeding, isolation and protection of cranial nerves and adequate tumour removal. 1 If a midline-~andibuloto~y approach is required, the

Fig. 63.5 Exposure of the parapharyngeal space.

external auditory meatus (EAM), the posterior border of the superficial surface of the parotid gland may be identified and freed superficially. Deeper dissection in this region is best deferred until the remaining skin flap has been raised. 4 The posterior skin flap should be elevated sufficiently

Fig. 63.6 Facial nerve trunk exposure.

Surgery for ~ara~baryngeal-s~ace Tumours 4 59 transcervical incision is carried up the midline of the neck to the level of the mandible, where it is curved laterally around the contour of the chin and back to the midline of the lower lip (Fig. 63.4). The lip is transected in the midline. Oncethe skin incision has been completed, the periosteum overlying the mandible is incised and elevated laterally for approximately 2 cm. The osteotomy is carried out through the incisor tooth socket, extracting the tooth if necessary (Fig. 63.7). 2 The osteotomy can be performed with a Gigli saw, reciprocatingsaw or Lindermanncuttingburr.The osteotomy must be anterior to the submental foramen. Prior to performing the osteotomy, drill holes must be made. This assists accurate relocation and wiring of the mandible. It is important that the osteotomy is bevelled in both a vertical and a horizontal plane. This provides adequate locking of the osteotomy once the jaw is wired together. 3 The floor of the mouth is incised along the lateral gutter, mid-way between the alveolus and the tongue base. The incision is extended from between the submandibularduct openings, alongthe floor of the mouth to the anterior tonsillar pillar. As the soft tissue inthe floor of the mouth is separated, using peanut dissection, the lingual and hypoglossal nerves are identified and preserved (Fig. 63.8). The postganglionic connections of the lingual nerve to the submandibular gland are divided. 4 The mylohyoid muscle is divided prior to performing lateral retraction of the mandible. TheICA and external carotidartery (ECA)are identified and secured with tapes, while the submandibular gland is retracted superiorly. The ECA is ligated and divided at the level of the facial artery.

Fig. 63.7 Mandibular osteotomy.

Fig. 63.8 Floor of mouth exposure.

Using one of thethreeapproaches described above, exposure of both tumour and skull base should be adequate to enable safe dissection and removal of the mass.

Prior to closure, haemostasis must be secured and all associated cranial nerves should be identified and documented as being intact. The area should be thoroughly irrigatedwithwarm saline and the digastric muscle sutured back into position. Oncethetumour has been resected, the mandible should be realigned and wired, using 25-gauge wire. The platysma is sutured, using interrupted 4/0 Vicryl. The woundis drained through a separatestab incision below the main incision, using a suction drain. A nasogastric tube is now inserted and left in place until the patient is able to feed orally. No wound dressing is necessary as direct visualisation of the entire operative site during the postoperative period is desirable. The incision line is covered, using an antibiotic ointment.

460

Chapter 63

ures the parapharyngeal space include the following: 1 double mandibular osteotomy (Attia et al., 1984); 2 anterior dislocation of the mandible (Johnson et al., 1989); 3 details regarding management of carotid paragangliomas are given in Davidge-Pitts and Pantanowitz (1984).

Attention must be paid to the following points in the postoperative management. 1 Adequate postoperative analgesia. 2 Stabilisation of the patient’s haemodynarnic status. 3 Documentation of cranial-nerve function. 4 Meticulousattentionpaid to functioning of the suction-drainage system to prevent haematoma. 5 Attentionshould be paid to intra-oral hygiene and hydration. 6 A nasogastric tubeis always inserted, as patients have difficulty in swallowing during the first few postoperative days. 7 Standardtracheostomycarewhereatracheostomy has been formed.

1 Postoperativehaemorrhage.This may occurasa complication of hypotensive anaesthesia if haemostasis is attemptedprior to normalisation of thebloodpressure. The wound must be reopened and bleeding arrested. 2 Weakness of the associated cranial nerves. The incidence of weakness should be extremely low. Any weakness is generaliy temporary and rarely lasts longer that 2-3 weeks. Hypoglossal-nerve palsy results in deviation of the tongue to the affected side. No action need be taken in a unilateral palsy. 3 Of particular relevance in these procedures is weakness of the angle of the mouth, which may occur if the mandibular branch of the facial nerve is not adequately protected. 4 Salivary fistula may occur as a result of procedures carried out to the parotid and submandibular gland. 5 Intra-oral salivary leak occurs asa result of inadequate closure of theintra-oral mucosal defect. It is extremely uncommon and should be treated conservatively. 6 Gustatorysweating in thepreauricular region at

Fig. 63.9 Floor of mouth closure.

mealtimes occurs in approximately 15% of patients who have had a parotidectomy-type approach.

References Attia EL, Bentley KC, Head T & Mulder D (1984) A new external approach to the pterygomaxillary fossa and parapharyngeal space. Head Neck Surg. 6, 884. Bass RM (1982) Approaches to the diagnosis and treatment of tumours of the parapharyngeal space. Head Neck Surg, 4, 281-9. Biller HE, Som P & Lawson W (1981a) Tumours of the parapharyngeal space: pre-operative evaluation, diagnosis and surgical approaches. Ann. Otol. Rhinol. Laryngol. 90 (Suppl. 80) (4), 3-15. Biller HF, Shugar JMA & Krespi YP (1981b) A new technique for wide-field exposure of the base of the skull.Arch. Otolaryngol. 107, 698. Cross RR, ShapiroMD 8c Som PM (1989) MRI of the parapharyngeal space. Radiol. Clin. North Am. 27 (2), 353-78. CurtinHD(1987) Separation of themasticatorspacefromthe parapharyngeal space. Radiology 163, 195. Davidge-Pitts KJ & Pantanowitz D (1984) Carotid bodytumours. Surg. Ann. 16, 203-27. Davidge-Pitts KJ, Van Hasselt A & Modi PC (1983) Parapharyngeal space tumours. South Afr. 1.Surg. 21 (2), 83-91. PW & Wiot G (1992) Muscle Freije JE,GluckmanJL,Biddinger tumours in the parapharyngeal space. Head Neck 14 (l),49-54. Heeneman H & Maran AG (1979) Parapharyngeal space tumours. Clin. Otolarylgol. 4, 57-66.

Surgery f o r ~ a r ~ p ~ a r y ~ g e aTumours l - s p ~ ~ e 461 .

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-L.

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Heeneman H, Johnson JT, Curtin H D et al. (1987) The Johnson J T , Myers E N & Curtin HD (1989) Tumours of the ParapharyngealSpace:Anatomy andPathologic C ~ ~ d i t ~ ~parapharyngeal ~ s space. In: MyersEN & Suen JY (eds) Cancer o f t h e withEmphasis onNeurogenous Tumours. Rochester, M N , SIPac HeadandNeck, 2nd edn. NewYork,Churchill Livingstone. AmericanAcademy of Otolaryngology-HeadandNeck Surgery Foundation.

e Infection G R A H A M J. C O X A N D B I P P O N

Many of the definitive descriptions of the naturalhistory and surgical management of patients with deep-neckspace infections were published in the era before effective antimicrobial agents were available. The dearth of recent publications may relate to a reduced incidence of the condition itself, or reduced morbidity and mortality due to earlier recognition using high-resolution imaging techniques. Nevertheless, the problems in establishing the precise diagnosis remain, due to the confusing clinical presentation, the difficulties in defining the precise aetiology and the differences of opinion regarding treatment. Descriptions of deep-neck-space infection occur in the medical literature of theMiddle Ages, with cases of retropharyngeal-space infection described by Galen and in the works of Platerus in 1625.

Surgical anatom The clinically important deep neck spaces are defined by the anatomy of the three layers of deep cervical fascia (Fig. 64.1). Superficial layer (investing layer) of deep cervical fascia

This layer has been described asthe‘mother’ of the cervical fasciae, as all themajor deep cervical fascial layers develop as septa from it. It is a well-developed layer that surrounds the neck and extends superiorly to the face and inferiorly into the axilla. It encloses two glands, theparotidandsubmandibular glands; two muscles, the trapezius and sternomastoid muscles; and two spaces, thesuprasternal space of Burns and the space of the posterior triangle. Inferiorly, it attaches to

C. VINAYAK

the spine of the acromion, the clavicle and the sternum, It extends circumferentially around the neck from the spines of the cervical vertebrae and contributes to the carotid sheath. Superiorly, it attaches to the body of the hyoid bone, crossing the submandibular and submental spaces to become attached along the inferior border of the body of the mandible up to the symphysis menti. It is attached to the sheaths of the digastric muscles as it covers them,thusforminga closed submental space. Posteriorly, it splits to enclose the parotid gland before being attached to the zygomatic arch, continuing over the temporalis muscle to the occiput, the mastoid process of thetemporal bone and theexternalauditory meatus (EAM). Middle (visceral) layer of deep cervical fascia (Fig. 64.2)

This layer encloses the larynx, trachea, oesophagus and thyroid gland and contributes to the carotid sheath. It sheathes the strapmuscles that attach tothe hyoid bone and thyroid cartilage. The middle layer is derived from the superficial layer of deep cervical fascia at the deep surface of the sternomastoid muscle. It encloses the two layers of infrahyoid strap muscles, forming three laminae, which are attached to the hyoid bone. At the lateral border of theomohyoid muscle, thelaminae fuse to form a continuous sheet of fascia across the midline of the neck, attached to the sternum, clavicle and anterior scapula inferiorly. The visceral component of the middle layer forms the false capsule of the thyroid gland,and is continuous with the fascia that covers the trachea and oesophagusinthe mediastinum. Itformsa relatively closed space around these viscera as they extend superiorly into the neck, becoming the larynx and pharynx.

Fig. 64.1 Cross-section of the neck at the level of the thyroid gland illustrating the three layers of the deep cervical fascia. (After Shumrick DA, Gluckman JL & Meyerhoff WL (1991) Otolaryngology. With permission from W.B. Saunders Company.)

Fig. 64.2 Midsagittal section to illustrate the fascial layers, spaces and surgical landmarks. (After Shumrick DA, Gluckman JL & Meyerhoff WL (1991) Otolaryngology.With permission from W.B. Saunders ComDanv.)

464

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~64 ~

t

e

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The visceral component then attaches to the skull base, the pharyngeal aponeurosis,the mandible and the pterygomandibular raphe. Posterior to the pharynx, it covers the constrictor muscles and buccinator, extending from the skull base to the level of the cricoid cartilage asthe buccopharyngeal fascia. The middle layer also largely forms the carotid sheath surrounding the common carotid artery (CCA), the vagus nerve and the internal jugular vein (IJV). The sheath has attachments to the visceral fascia medially along the midposterior surface of the pharynx, from thebase of the skull to the level of vertebra C”. The sheath is attached to the prevertebral and investing layers of deep cervical fascia as it covers the deep surface of thesternomastoid muscle, and to themiddle layer of deep cervical fascia along the lateral border of the sternothyroid muscle. The sheath is attached to the fascia covering theposterior belly of digastric and stylohyoid muscles superiorly.

(Fig. 64.3) The deep layer is divided into thepre-vertebral layer and the alar layer. The pre-vertebrallayer lies anterior to the bodies of the cervical vertebrae, just anterior to longus colli, longus capitis and the anterior longitudinal ligament of the vertebral column. It extends to the midthoracic region inferiorly and laterally it fuses with the tips of the transverse processes of the cervical vertebrae. It continues posterolaterally, sheathing thescalene

\bone

muscles and erector muscles of the spine before being attached to the spines of the cervical vertebrae. The alar layer lies just anterior tothe prevertebral layer and deep to the middle layer. It extendsfromthe midline of the neck to the tips of the transverse processes, and is attached to thecarotid sheath. Itis attached inferiorly to the base of vertebra T2, fusing at that point with the visceral fascia. Itextends superiorly to the skull base. It is important clinically, as it separatesthe retropharyngeal space from the parapharyngeal space.

The mortality rate from deep-neck-space infections has reduced since the preantibiotic era, although death from uncontrolled sepsis or from a significant complication still occurs. Whenever a deep-neck-space abscess is identified, surgical drainage must be considered to prevent further spread of infection and to allow resolution before complications occur. Surgical intervention may be required to protect an embarrassed airway and to prevent aspiration of purulent material into the respiratory tract. Surgical intervention may also be required to remove a foreign body fromthepharynx or upper oesophagus which may be associated withthe deepneck-space infection.

The diagnosis of deep-neck-space infections is often

Fig. 64.3 Oblique cross-section from the level of the hyoid inferiorly, emphasising the relationships among the various spaces. Note the connections of the parapharyngeal space with the retropharyngeal and prevertebral spaces and carotid sheath. (After Shumrick DA, Gluckman JL& Meyerhoff WL (1991) Otolaryngology. With permission from W.B. Saunders Company.)

Deep-neck-space Infection difficult. It may not be easy to distinguish an established deep neck abscess from either diffuse cellulitis or inflammatorylymphadenopathy.The clinical features that suggest deep-neck-space abscesses include fluctuating pyrexia, pain, dysphagia or odynophagia, neck swelling, trismus and torticollis. These rnay be masked by antibiotics takenprior to presentation. Airway embarrassment is not uncommonwithretropharyngealand parapharyngeal-space infection and with Ludwig’s angina. It may be possible from the historyto establish the source of the sepsis, but the initiatinginfection may have resolved prior to the neck-space infection becoming established. Common sites are dental infections, tonsillitis and nasopharyngitis. Historically, tubercular infection of the cervical spine and pharynx was an important aetiological factor and it may remain so in underdeveloped countries. With the widespread use of antibiotics, spread of infection from upper airway lymphoid tissues is becoming less common,whereasintravenousdrug abuse, ingested foreign bodies and instrumental trauma are becoming more important causes. There is a high incidence of associated systemic disease, such as diabetes, immunosuppression, AIDS and HIV infection. The presence of these associated conditions may affect the surgical management of the patient.

Themanagement of deep-neck-space infections is to establish formaldependentdrainage of thecompartments involved, togetherwithappropriate high-dose systemic antibiotics. The incision must allow adequate exposure to identify the anatomical landmarks and important structures of the neck, as well as allowing exposure of the abscess cavity itself. Incisions arenot primarily cosmetic, and adequate flap development and retraction are often requiredto allow safe dissection and identification of anatomical landmarks. The induration and oedema of the soft tissues associated with such infection often distort the anatomyand it is often essential to identify bony and cartilaginous structures,such as the cricoid cartilage in the midline, the greater cornuaof the hyoid bone laterally and the styloid process superiorly. Important muscular landmarks include the anterior border of the sternomastoid muscle and the anterior and posterior bellies of the digastric muscle.

465

The retropharyngeal space lies behind the pharynx and upper oesophagus, extending from the skull base to the level of vertebra T1 or T2, where the middle and deep layers of cervical fascia fuse. Posterior to this space lies the pre-vertebral space (danger space), extending from the skull base to thediaphragm and laterally to the transverse processes of the vertebrae. Infection can track from the retropharyngeal space through the alar fascia intothedanger space andthusinto theposterior mediastinum, Clinical mani~estati

Infection in this space usually results from involvement of the retropharyngeal lymph node in infections of the adenoids, nose andparanasal sinuses ininfants and young children. It may also occur as a result of pharyngeal perforation from foreign bodies or instrumentation, from the spreadof dental or otological infection or from spinal tubercular disease. In children the onset may be insidious. The signs and symptoms of a severe upper respiratory infection are present, with the neck held rigid, often with torticollis due to spasm of the involved muscles. There may be an associated dislocation of the cervical vertebrae. There is associated tender cervical lymphadenopathy and deepseated pain. Laryngeal oedema rnay compromise the upper airway, with signs of airway obstruction. On examination, a definite midline swelling of the posterior pharyngeal wall can be seen. Should palpation be required to establish the diagnosis, it should be gentle to prevent rupture of the abscess and subsequent aspiration. In adults, the signs and symptoms are largely pharyngeal, with dysphagia, dyspnoea, pharyngeal pain, nasal obstruction and cervical lymphadenopathy. Grave complications may occur, including haemorrhage and rupture intothe airway, withlaryngeal spasm and aspiration. The infection may spread into the prevertebral space and so into the posterior mediastinum, or into the parapharyngeal space. Operative tee

Peroral approach

The retropharyngeal abscess can be drained through the

466

Chapter 64

open mouth, either without anaesthesia or under local topicalanaesthesia.This may be the safest approach with an infant in extremis. It is essential to have the head in an extreme dependent position to prevent aspiration, and to have a good light and suction to hand. Using a mouth gag, a vertical incision is madethroughthe mucosa and the<_abscesswidely openedwitha large clamp andthe contentsaspiratedwithsuction. Pus should be sent for microscopy, culture and sensitivity studies. If airway obstruction is present, tracheostomy or cricoid thyroidotomy may be requiredprior to drainage. With a less acute abscess, a peroral approach may be used with a general anaesthetic technique. The anaesthetic requires an experienced and senior anaesthetist, who will usually use a gaseous inhalation technique with the patientsupine and head down. Intubation must be performed with great care to prevent rupture of the abscess. Once the patient is intubated with acuffed oral endotracheal tube (ET), the patient is positioned supine with the head dependent and a Boyle-Davis mouth gag inserted. The mucosa is incised and the abscess drained as before. The infection may have rendered the neck unstable so extremecare is required in handling and positioning the patient to prevent damage to the spinal cord.

studies. A large corrugated or soft rubber Penrose drain is inserted into the depths of the cavity and secured with arobustsuture to the skin. The skin incision is closed loosely with simple interrupted non-absorbable sutures. The drain should be removed when clinically appropriate, usually after &” days. High-dose IV antibiotics should be used. A combination of athird-generation cephalosporinwithmetronidazole oran extendedspectrum penicillin with anaerobic cover is usually appropriate until culture studies are available, but if the patient is very toxic microbiological advice should be sought. Posterior external approach (Fig. 64.5)

A n alternative approach is via a skin incision along the posterior border of the sternomastoid muscle. The patient is anaesthetised and positioned as for the anterior external approach. This approach avoids the branches

Anterior external approach (Fig. 46.4) This approach allows drainage of the retropharyngeal space, danger space, prevertebral space and visceral vascular space. The patientis usually intubated with an oral ET and under general anaesthesia. Exactly the same care is required in establishing anaesthesia as in the peroral approach. Thepatient is positioned supine with theneck extended and rotatedaway from theinvolved side as far as can be safely achieved. A skin incision is made along the anterior border of the sternomastoid muscle at the required level between the sternum and hyoid bone. The incision should be substantial in order to allow safe and adequate access. Using blunt-finger dissection where possible, the sternomastoid muscle and carotid sheath are retracted laterally. The thyroid gland, superior thyroid vessels and superior laryngeal nerve are retracted medially. The abscess can thusbe exposed at the Level of the hypopharynx. The omohyoid muscle, middle thyroid vein and inferior thyroid artery may need to be divided for adequate access. The abscess is opened with abluntclamp. Using a finger, theopeningcan be widened and extended as necessary. Finger dissection can be used down to the level of the sternum butcollections below the clavicle may requiredraining via a thoracotomy. Pus should be sent for microbiological

Fig. 64.4 (a) Incision for the anterior approach for exploration of retropharyngeal or visceral space infections. (b)Routes for exploration of retropharyngeal or visceral spaces. (After Shumrick DA, Gluckman JL & Meyerhoff WL (1991)Otolaryngology. With permission from W.B. Saunders Company.)

Deep-neck-space Infection

467

and there is induration and swelling externally in the region of the angle of the mandible and tail of the parotid gland. Infection within the retrostyloid compartment does not produce trismus. It is associated with medial displacement of theposterior pillar of the tonsil and posterolateral pharyngeal wall. External induration and swelling of the parotid-space area may occur. Carotidsheath involvement may result in thrombosis of the IJV and rarely haemorrhagefromerosion of theinternal carotidartery(ICA). Involvement of bothcompartments results in a combination of symptoms, together with significant systemic signs of sepsis. Fig. 64.5 Incision for posterior approach to the retropharyngeal or visceral spaces. Blunt dissection is carried out posterior to the sternomastoid muscle and carotid sheath. (After Shurnrick DA, Gluckman JL & Meyerhoff WL (1991) Otolaryngology. With permission from W.B. Saunders Company.)

Operative technique (Fig. 64.6)

Drainage of the parapharyngeal space is performed un-

of the external carotid artery (ECA) and IJV. With blunt dissection, the deep cervical fascia posterior to the sternomastoid muscle is identified and blunt dissection carried out posterior to thecarotidsheathuntilthe abscess is reached. Drainage and skin closure areas described for the anterior approach.Systemic antibiotics as suggested for the anterior approach are appropriate.

Parapharyngeal-space infections (pharyngornaxillary space, lateral pharyngeal space, peripharyngeal space) Surgical anatomy

The parapharyngeal space is cone-shaped, with its base located at the skull base and its apex at the hyoid bone. The space is divided into two by the styloid process and its attached muscles. The anterior part is closely related to the tonsillar fossa medially and the medial pterygoid muscle laterally. The posterior part contains the carotid sheath and the last four cranial nerves. Clinical manifestations

Parapharyngeal-space infection usually results froma spread from a focus in the pharynx, tonsil or adenoids, or as an extension from a peritonsillar abscess. Rarely, spread may result from mastoid and middle ear infefection via a Bezold's abscess. Infection within the anterior part of the Parapharyngeal 'Pace is associated with marked trismus from irritation of the medial pterygoid muscle. The tonsi1 and lateral pharyngeal wall are displaced medially

Fig. 64.6 (a) Standard incision for exploration of the parapharyngeal space. Note the vertical limb for exploration of the carotid sheath if extension into the neck is suspended. (b)Approach to parapharyngeal space passing posterior to the tail of the submandibular gland and medial to the mandible. This can usually be accomplished withblunt dissection. (After Shumrick DA, Gluckman JL & Meyerhoff WL (1991) Otolaryngology. With permission from W.B. Saunders Company.)

468

Chapter 64

der general anaesthesia withthepatient supine. The neck is extended as far aspossible, and the head rotated away from the involved side. The important anatomical landmark is the tip of the greater cornua of the hyoid bone. A transverse skin-crease incision is made at this level, which avoids damage to the mandibular branchof the facial nerve. The incision should be long enough to allow adequate flap development and exposure. Using blunt dissection or finger dissection, thetip of the greater horn of the hyoid is identified. The ECA should lie just lateral to it. Careful finger dissection is carried out until the tip of the styloid process is reached by elevating the submandibular gland and ECA. The facial and lingual veins may require ligation. By sliding the finger alongtheposterior belly of the digastric and sty~ohyoidmuscles, the styloid process is reached within the,parapharyngeal space. The skull base may be reached, and exposure of theparapharyngeal space achieved by following the carotid sheath down into the neck. Corrugated drains or soft rubber Penrose drains are inserted superiorly and inferiorly and secured. The wound is loosely closed with interrupted non-absorb-

ablesutures. Pus is sentfor microscopy, culture and sensitivity studies and the patient commenced on a similar regimen of antibiotics to thatdescribed in the section on retropharyngeal infection.

Further rea Everts EC & Echevarria J (1980) Diseases of the pharynx and deep neck infections. In: Paparella MM & Shumrick DA (eds) Otolaryngology. Philadelphia, W.B. Saunders Company, pp. 230222. Levitt GW (1976) Cervical fascia and deep neck infection Otolaryngol. Clin. North Am. 9 ( 3 ) , 703-16. Lindner HH (1986) The anatomyof the fasciae of the face and neck with particular reference to the spread and treatment of intraoral infections that have progressed into adjacent fascia spaces. Ann. Surg. 204 ( 6 ) ,705-14. Paonessa DF & Goldstein JC (1976) Anatomy and physiology of head and neck infections. Otoluryngol. Clin. North Am. 9 (3), 561-80. Shumrick KA & Sheft SA (1991) Deep Neck Infections. In: Paparella MM, Shumrick DA, Gluckman JL & Meyerhoff WL (eds) Otolaryngology. Philadelphia, W.B. Saunders Company, pp. 254563.

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ic Prominent ears are relatively common. However, many individuals never seek any treatment, despite a significant deformity. The majority of prominent ears are evident by 5 years of age, and body image awareness develops 1-2 years later (Tan & Gault, 1995). Thus, children with prominent ears start to be teased around this age. Poor self-perception and more social and attention problems are notedin children with prominent ears as compared with normal peers (Sheerin et al., 1995). Many parents request correctionat anearly age because of concerns for their child. Correction is indicated when the child andlor parentperceives that the ear(S ) protrude abnormally. Since approximately 10% of patients continue to suffer fromdisturbance of body image after correction, it is important to assess these patients carefully (Sheerin et al., 1995).

Local

Inflammatory conditions: 0 eczema; 0 otitis externa. Surgery should be avoided until local infectionlinflammation is eradicated or controlled, in order toreduce the risk of wound infection and chondritis. Systemic

Bleeding disorders. 0 Steroid treatment. Surgery in the presence of a significant bleeding disorder, such as haemophilia and thrombocytopenia, would 0

be contraindicated,due to theuncontrolled bleeding and risk of haematoma formation. Caution is recommended in patients on long-term steroid treatment, because of the effect onwound healing and risk of infection.

The generalised distress over multiple body parts should be approachedwithcaution,asa significant number of these patients will be dissatisfied following surgery.

Because of the risk of poor scars inpatientswith pigmented skin or apast history of hypertrophic or keloid scars, careful counselling is necessary.

e At the time of interview, it is importantto elicit the patient’s andlor parents’ concerns with respect to the perceived deformity. Any relative or absolute contraindications to surgery are identified and discussed. Examination of the patient should include a general assessment of the patient’s well-being in consideration of the proposed surgery and anaesthesia. The deformity of the ear(s) should be accurately identified and recorded. The prominence may be the result of an abnormal scaphaconchal angle, which is normally acute. The antihelical fold may be absent, the concha may be abnormally deep and cupping of the helical margin may be noted.

472

Chapter 6.5 and other deformities (Tan & Gault, 1995). Treatment can be provided with minimal cost and surgical intervention avoided. Thermoplastic splints are easy to prepare and well tolerated when used in the first 3 months (Fig. 65.1). Neonatal referral should be encouraged to optimise early correction. There is no optimum age for surgical correction and the timing of surgery should take into account the degree of deformity, age, the patient's andlorparents' desires and the anaesthetic technique proposed. Generally, surgery is performed at the age of 4 or 5 years, when parental concerns about teasing encourage early correction. Later correction is supported and allows the option of surgery under either local (LA) or general anaesthetic (GA).

Anatomy (Fig. 6 5 2 )

Fig. 65.1 Thermoplastic splint moulded to helix.

The normal ear is almost fully developed by 6 years. Normal conchal depth varies from 10 to 15mm. The helical rim protrudes about 10-2Omm from the scalp at an angle of 21-25' (Snively, 1994; Fig. 65.3).

Operati scoring Preparation Anaesthesia The use of either GA or LA should be discussed with the child andlor parent. LA is well tolerated at the age of 9

Fig. 65.2 Anatomical landmarks of the pinna and auricular cartilage.

The deformity may be the result of one or more factors and may be unilateral, bilateral, symmetrical or asymmetrical, which should be pointed outto the patient. Since approximately 85% of ears become prominent by 6 months of age, a simple splintingtechnique duringtheneonatal period cancorrect prominence

Fig. 65.3 Normal position of the pinna.

depth is measured and assessment madeas to the amount of reduction required. Theline of the antihelical fold is tattooed, using a needle or silk suture passed through the ear. The posterior skin excision is planned in an elliptical pattern, with the posterior line at the sulcus (Fig. 65.5). The excision should bring the helical margin to 1.5-2 cm of the mastoid (Snively, 1994). The upper point of the excision should be kept below the superior sulcus to avoid the eventual scar being visible over the top of the ear. Procedure

Skin excision The posterior skin is excised, including the soft tissue, down tothe perichondrium. The anterior skin margin is elevated by sharp dissection towards the rim. Haemostasis is obtained, using bipolar coagulation. Cartilage incision Fig. 45.4 Nerve supply to the pinna.

or 10years and is to be preferred. The use of a eutectic mixture of local anaesthetic(EMLA)cream reduces thepain associated with local infiltration(Slator & Goodacre, 1995). General anaesthesia is required in the younger child and the services of an experienced anaesthetist should be available. A mixture of bupivacaine (0.25%)and lignocaine (1Y o ) with adrenaline 1:200 000 is used to anaesthetise the ear, whether for local or general anaesthesia (Roberts et aE., 1992). Thegreaterauricular nerve is first blocked at the lobule, with subsequent infiltration along the postauricular sulcus to block the lesser occipital nerve (Fig. 65.4). Anteriorly, the auriculotemporal nerve is blocked in front of thetragus. Lastly, the conchal fossa is infiltrated in subperichondral a plane and this hydrodissection facilitates later cartilage dissection.

The tattooed marks are identified and the line of cartilage incision is marked about 1cm lateral to these (Fig. 65.6). The line is carried superiorly and curved towards themastoid in the region of the inferior crus of the antihelix. Inferiorly, the line crosses the cauda helicis and curves posteriorly. With the index finger providing counterpressure and asa guide on the anteriorsurface of

Other

The patient is placed supine on a head ring, with a headup tilt of about 15". Long hair should be tied up and the skin carefully cleaned with a chlorhexidine or iodine antiseptic solution. cisi

The ear is folded back into the desired position and the line of the antihelical fold is marked with ink. Conchal

Fig. 65.5 Posterior skin excision.

474

Chapter 65 final adjustments carried out prior to proceeding to skin closure. C~osure/~ressings

1 Haemostasis is confirmed priorto closure witha subcuticular 410 or 3/0 prolene suture tied loosely over a paraffin-gauze dressing. 2 Proflavin wool is used to gently packtheconchal fossa, scapha and triangular fossa. Care is taken to avoid pressure on the antihelical fold. The ear is then covered with a further layer of proflavin wool and a single layer of gauze and wool. The head bandage is completed witha crepe bandage (locm), wrapped firmly to provide support, but avoiding excessive pressure. Elastoplast tape is used to secure the bandage to prevent inadvertent removal.

Postoperative management Fig. 65.6 Exposure of tattoo marks and marking for cartilage incision.

the antihelix, the cartilage is incised, avoiding the anterior skin. Cartilage exposure and scoring (Chongchet, 1963)

The incised cartilage is dissected fromtheanterior skin in a subperichondrialplane, using a Mitchells’ trimmer to expose the tattoo marks in the cartilage. The cartilage is then folded to simulate the correctantihelical fold. Parallel scoring of the cartilage is performed with thepoint of a no. 15 scalpel blade, starting atthe inferior crus and passing caudally to cross the incised cartilage (Fig. 65.7’). Scoring is repeateduntilthe cartilage folds easily at the line of marksand the desired antihelical fold is obtained. The upper helical margin is partially transected at the point of the superior crus, using scissors. Care is taken to avoid cutting across the margin, as a sharp edge would result. Complete division of the cauda helicis is confirmed, to ensure that the helical rim will be set back in thecorrected position. Cross-scoring of the cauda helicis may be required to reduce the projection in the lower third and lobule. Conchaldepth is reduced by folding of the antihelix. However,with an excessively deep concha and wide scapha, itis necessary to excise a strip from the lateral edge of the incised cartilage prior to scoring the anterior surface. Symmetry should be confirmed and

1 Oral analgesia is prescribed for 3 days. 2 The patient is advised to return tothe ward if there is any bleeding, severe pain (not controlled by simple analgesics) or displacement of the bandage. 3 The bandage is removed at 10-14 days and the suture removed. 4 A light bandage or elastic headband is worn at night for a further 4 weeks to prevent the pinna being folded forward during sleep.

Fig. 65.7 Anterior scoring.

Pinnaplasty 5 Out-patient review is arranged at 6 weeks and 6 months.

Corn Early

1 Nausea and vomiting-may be related to packing of the external auditory meatus (EAM) and concha (Ridings et al., 1994). Nausea and vomiting are rare in patients operated under local anaesthesia. 2 Haematoma-avoided by careful haemostasis. This should be drained urgently to avoid skin necrosis and infection. 3 Skin necrosis-commonly occurs over the antihelical fold due to excess pressure, and care with the dressing should avoid this. 4 Infection-should be rare. Chondritis may result. Late

1 Asymmetry. 2 Inadequate correctionlrecurrence. 3 Retroposition/loss of posterior sulcus. 4 Hypertrophidkeloid scar.

4.75

minor complications are common, with suture sinuses (due to the non-absorbable sutures utilised) and recurrence of prominence being themost significant. The technique is suitable for correctionof prominence in the younger child (4 to 5 years), in whom the soft cartilage folds easily. Alternatively, Mustardk-type sutures may be used in conjunction with anterior scoring to achieve the desired antihelical fold. Percutaneous scoring

Percutaneousanterior scoring was first described by Stenstrom in 1963,but thetechniquehas not been widely accepted. Anterior scoring can be performed with a 19-gauge hypodermic needle via a percutaneous approach. Correction is feasible in patients in which the deformity is confined to a poorly developed antihelical fold. After scoring, tissue glue is used to hold the helix in thecorrectedpositionfor 2-3 weeks. The technique requires considerable experience in scoring the cartilage blindly and thus can produce inconsistent results. The main advantage of percutaneous scoring is avoidance of the posterior skin incision. The procedure is also quick and well tolerated by the patient.

References e (Mustardk, 1967)

Folding of the antihelix: is achieved by the use of multiple mattress sutures placed posteriorly. The position of the desired antihelical fold is marked andtattooed,and skin excision is performedas described previously. Care is taken to excise all the soft tissue overlying the perichondrium, as this would prevent the satisfactory folding of the cartilage. The ear is then set back with the cartilage folded into the desired position and the position marked for the sutures. Approximately three non-absorbable, braided, sutures(4/0 Ticron or Ethibond) are inserted, Each suture is passed through the full thickness of the cartilage, avoiding the anterior skin. The sutures are all placed prior to tying, allowing the correctedposition to be adjustedwith tying of each suture in turn. Care is taken to avoid overcorrection. Symmetry should be checked prior to skin closure. The Mustard6 technique can acheive good results. However,

Chongchet V (1963) A method of anthelix reconstruction. Br..] Plast. Surg. 16 (3), 268-72. Mustard6 JC (1967) Thetreatment of prominent ears by buried rnattress sutures-a ten years’ survey. Plast. Reconstr. Surg. 39, 382-6. Ridings P, Gault DT & Khan L (1994) Reduction in postoperative vomiting after surgical correction of prominent ears. Br. J.Anaesth. 72 ( 5 ) , 592-3. Roberts RH, TanST & Sinclair SW’ (1992) Lignocaine vs bupivacaine in prominent ear correction: a controlled trial.Br. J . Plast. Surg. 47 (7), 533-5. Sheerin D, Macleod M & Kusumakar V (1995) Psychological adjust] Am. ment in children with port-wine stains and prominent ears. . Acad. Child Adolesc. Psychiatry 34 (12), 1637-47. it Slator R & GoodacreTE (1995) EMLA cream on theear-is effective? A prospective, randomised controlled trial of the efficacy of topical anaesthetic creamin reducing the pain of local anaesthetic infiltration for prominent ear correction. Br. J.Plast. Surg. 48 (3), 150-3. Snively SL (1994) Plastic surgery of the ear. Selected Readings Plast. Surg. 7 (16), 1-26. Stenstrom SJ (1963) A natural technique for correction of congenitally prominent ears. Plast. Reconstr. Surg. 32, 509. Tan ST & Gault DT (1995)When do ears become prominent? Br. J. Plast. Surg. 47 (8), 57’3-4.

Cutaneous defects of the face result mainly from tumour excision or trauma. Basal-cell carcinomas (BCCs) are among the most commonof all tumours and their inadequate treatment can result in morbidity and mortality which is often underestimated. Fear of reconstruction and ignorance of whatcan be reconstructed may at times result in either incomplete excision or use of the wrong treatment modality. Direct suture is preferred if there is no undue tension on the wound edges (Fig. 66.1) and no distortion of facial structures,particularly lips and eyelids, where functionas well asformcan be altered.Whenthe wound cannot be closed directly, there are three main alternative methods of reconstruction. These are: 1 skin grafting (full or split thickness); 2 a flap (local or distant); 3 laissez-faire (allowingthewound to granulate and heal by secondary intention). An enormous numberof local cutaneous flaps have been described for use on the face (Smith & Sherrell, 1991; McGregor & McGregor, 1995) anda description of all of them is beyond the scope of this chapter. The authors will therefore concentrate on the principles of local flap reconstruction of the face, using illustrative examples. The fundamentals of preoperative preparation, operative technique and postoperative care will be described. While it is acknowledged that facial flaps are a useful method of reconstruction,the authors would like to make the point at this stage that these are techniques that require training and experience. To quote McGregor & McGregor (1995): ‘It must be stressed before describing local flaps in detail that they are not procedures to be embarked on lightly. The surgeon us-

ing such a flap should remember always that a major vascular disaster is liable to leave a deformity far greater than the one theflap was designed to relieve.’ In particular, dangers of a badly designed reconstruction around the eyelids needs to be emphasised.

By definition, acutaneous flap is skin that has been transferred into a defect with its blood supply intact, as distinct froma skin graft,whichhas been separated from its blood supply. A graft must obtain nourishment from its recipient bed to survive. The skin of the face is highly vascular, being supplied with a rich dermal and subdermal plexus. It is due to this property that so many different flaps are possible on the face and that these flaps can sometimes be raised with a great length-to-breadth ratio without compromising their blood supply. In some cases flaps of great dimensions can be raised because their anatomy is such that a so-called ‘axial’ vesselis present (McGregor & Jackson, 1972).Where no such vessel is sought, the flap is termed random rather than axial (Fig. 66.2). The plane of dissection of random facial cutaneous flaps is at the level of the subcutaneous fat(Fig. 66.3), in order that the subdermal plexus on the undersurface of the skin is maintained and the underlying facial muscles and nerves are not damaged. Facial-nerve branches to the eyes and mouth are especially at risk and the relationship of such nerves to platysma should be learned. The thickness of the flap can be tailored to the depth of the defect by adjusting the amount of subcutaneous fat left on the flap. Overthinning is hazardous, however, and can always be left for later when the flap has been incorporated and is ‘self-sufficient’.

Fig. 66.1 Correct placement of lines is achieved by asking the patient to smile or frown.

J

i

I

Fig. 66.3 Plane of dissection for facial flaps. Skin is raised with some subcutaneous fat. The amount of fat can be tailored to the thickness of the defect.

Fig. 66.2 (left) (a) In ‘random’ skin flaps the skin is nourished via the dermal-subdermal plexus with a random contribution from the nearest perforating vessel. (b) In ‘axial’ flaps a known vessel runs longitudinally through the tissue allowing a longer flap to be raised safely.

478

Chapter 66 Woundsshould be placed, whenever possible, within skin-crease lines. These can be discovered by asking thepatient to frownor smile and may be marked preoperatively. Skin lines are often ill-understood and

Fig. 66.4 The face divided into its cosmetic units.

Fig. 66.6 Lines for placing scars in the face and neck, shown by the pattern of wrinkling, and their relation to the lines of the underlying muscles of facial expression (from McGregor & McGregor, 1995).

Fig. 66.5 The face divided into its cosmetic units.

The face itself is divided into cosmetic units (Figs 66.4 and 66.5). When studied closely, facial skin varies in thickness, texture and colour in each of these units (e.g. eyelid skin is very different from cheek skin). That is why inlocal flap design, if possible, a flap from the same cosmetic area is used to obtain the best cosmetic result.

Fig. 66.7 (as Fig. 66.6).

Facial Reconstruction with Local Cutaneous Flaps

479

the interested reader should refer to the excellent work there may be lax skin in an elderly face, it is inelastic, of Gibson (1977) in this regard. Therearealso specific and this may prevent the use of certain flaps in older areas on the face wherethere is increased skin laxity, patients. which can be utilised in flap reconstruction (e.g. glabellar and nasolabialareas).Most faces showa fairly ~ n d i ~ ~ ~ i * n ~ standard pattern of wrinkling, particularly in the elderly (Figs 66.6 and 66.7). factors many There are to be considered planning when Two main categories of flap movement have been a local flap. These include the following: 1 age of the patient and elasticity of the skin; described. These are: (i) rotation; and (ii)transposition. 2 size, site and nature of the defect; Rotation flaps move in the arc of a circle of which the 3 pathological process causing the defect; ‘pie-shaped’ primary defect is a segment. Skin closure is 4 any previous treatment to the area (e.g. surgery or by redistribution of tension over the extended suture radiotherapy); line. Withtransposition flaps, the main movement is 5 experience of the surgeon (no trainee should ever be lateral in direction, based on a pivot point to fill the gap, criticised for grafting a defect). leaving a secondary defect which may be closed directly The indications are as follows: or require grafting. In practice, most flaps combine both 1 forreconstruction using skin of similar thickness, movements (Figs 66.8 and 66.9). colour and type (e.g.’cheek skin into cheek defect, nasal Most flaps depend on a degree of elasticity in the skin skin into nasal defect, etc.); to reconstructthe defect andaretherefore easier to 2 whenthe bed of thewound is unable to be skinperformin younger patients.With age there is a degrafted (e.g. exposed cartilage, bone or tendon); crease in the elasticity of the skin, so that, even though

Fig. 66.8 (a, b)Rotation flap. Defect closed completely with ‘backcut’ to relieve tension. In theory, this narrows the flap bgse and increases the chance of ischaemia. It is not generally aproblem in the head and neck. (c, d) Transposition flap. A transpositionflap leaves a donor defect, which generally requires grafting. This flap

can be useful on the scalp, wheretheoutertable has been denuded of pericranium and will not accept agraft. The flap must be carefully raised in the elderly to preserve the flimsy pericranial layer in order that thesecondary defect may be grafted.

480

Chapter 66

Fig. 66.9 Local tissue is moved into the defect. Once the primary defect is sutured, then closure of the secondary defect is often achieved by redistribution of the available tissue.

3 when a robust reconstruction is required which contracts less than a graft.

ontraindieations 1 Previous surgery resulting in scars acrosstheproposed flap. 2 Previous radiotherapy in thearea of theproposed flap. 3 When thesurgeon is uncertain of the excision margins in tumour surgery. 4 When the surgeon needs to monitor for tumour recurrence (e.g. morphoeic BCC).

Preoperative managemen Preoperative assessment of a patient who is to have a facial flap is mainly derived from history and examination. Rarely are investigations necessary, and those that areperformedwould be to assess general premorbid conditions that would impair wound healing. X-rays, scans or ultrasound may be indicated, especially in the periorbital or auricular areas, if a malignant tumour is invading widely and resection of the tumour may interrupt the blood supply of the proposed flap. A history of

aspirin ingestion should be elicited specifically and may be an indicationforin-patientstay.A biopsy result, when performed, may make flap reconstruction unwise. Broadly speaking, preoperative assessment is divided into local and general factors(Table 66.1). General factors commonly affecting flap reconstruction are those connected with wound healing or clotting (see Complications). Smoking is another important consideration which has deleterious effects on flap circulation. It is the authors’ preference to provide diabetic patientswith antibiotic cover, although the evidence for its efficacy is anecdotal. In general, only two or three perioperative doses are required.

era Anaesthesia For most facial flaps, use local (LA) or regional anaesthetic, with either short-acting lignocaine or long-acting Marcain(withadrenaline, either 1 in 80000 or 1 in 200 000, for vasoconstriction).To decrease the pain, the LA should be injected slowly to avoid increased tissue tension and with a fine needle. There are 32-gauge nee-

Facial Reconstruction with Local Cutaneous Flaps

48 I

Table 66.1 Preoperative assessment plan of a patient who is having facial flap reconstruction.

dles now available and they can be used with or without a dental syringe. The solution should not be overchilled. Also, by adding bicarbonate to the LA, it reduces the pain on injection of the solution by decreasing its acidity (Mckay et al., 1987). For large flaps or extreme patient anxiety, use general anaesthesia. Before facial flap incisions and in the case of tumour excision, the incision lines should be drawn before the LA is injected as it distorts tissue planes and blurs tumour edges. The use of magnifying loupes improves accuracy and suture placement. Other drugs

1 Antibiotics are not used routinely for facial flap surgery, but theiruse to combatBacteroides may be considered if the oral ornasal cavities are breached. Infections are extremely rare in surface wounds because of the good blood supply of the tissues. In the authors’ experience, cigarette-smokers have morewound infections and should be warned of this fact. 2 If a patient is on steroids, a maintenance dose should be given. No supplement is necessary. 3 Sedation may be useful in anxious patients. This can be given simply in the oral form (e.g. temazepam). IV sedationshould be given by trainedanaesthetic staff withpropermonitoring and resuscitation equipment present. 4 Anticoagulants (e.g. aspirin, warfarin) can be continued for facial flap surgery. Meticulousintraoperative haemostasis and postoperative pressure dressing are required. Patients on warfarin do not need to cease this and be heparinised, as they do for major surgery. Drains are used infrequently but have a place.

Patient positioning and set-up

When possible, the patient should be in a head-up position. It is helpful if the eyes are covered with a moist swab, since many LA patients complain of discomfort from the brilliance of the theatre lamps. The authors prefer to design the flap, markthe defect and then slowly infiltrate LA, using a dental syringe. This can be done extremely slowly with minimal forceful needle advancement. The procedure should be virtually painless. After completion of infiltration, some time should elapse before scrubbing and preparingtheoperative field. The authors never use alcohol-based solutions for skin preparation. Bipolar diathermy is accurate and infinitely preferable to monopolar in almost all cases. Flap designs

Many flaps have been designed in the head and neck. Some of those most commonly used are now described. Cheek rotation flap

This can be used for extensive lid defects where greater than one-third of full thickness lid is excised. It is usually combined with a chondromucosal graft from the septum for lining (Figs 66.10 and 66.11). In almost all cases, the lateral canthal ligament requires division of its lower portion to allow mobilisation.The flap must be designed higher on its lateral aspect than imagined and the medial aspect of the defect should be as vertical as possible. Initially described by Mustard6 (1980) in theaboveforms, an elegant modification incorporating a Z-plasty in the outer part

482

Chapter 66

Fig. 66.10 With small defects closure is possible without grafting.

incisions

Defect removed; postauricular flap moved preauricularly

Defect closed using principle of halving

Fig. 66.11 With larger defects the donor deficit may require grafting. In this case the secondary defect has been filled with a postauricular flap. The postauricular defect can then be primarily closed.

of the flap has been described by McGregor and McGregor (1986) to reconstruct upper and lower lids (Fig. 66.12). Glabellar flap

This flap takes advantage of midline laxity of the forehead skin between the eyebrows. It is useful for upper nasal bridge and medial canthal defects. The flap brings the eyebrows together and may produce a bizarre appearance in patients whose eyebrows are confluent preoperatively (Figs 66.13 and 66.14). This flap is basically an advancement into a triangular

Fig. 66.12 A Z-plasty at the end of the flap allows lengthening and primary closure.

Facial Reconstruction with Local Cutaneous

Flaps

4.83

Fig. 66.13 In nasal bridge or canthal defects the glabellar skin can be moved in various ways with the defect being closed primarily.

Fig. 66.14 (as Fig. 66.13).

defect. It should be used with caution if clearance margins are questionable. Nasolabial flap (Figs 66.15 and 66.16)

This flap is useful since the donor defect ends up in a natural crease line, namely the nasolabialfold. If the flap is designed too low, the transpositionbecomes too great and the nasal-cheek angle is obliterated. Like all superiorly based flaps, this may become bulky in time. This flap, of apparently simple design, is frequently illexecuted.

useful on the cheek and temple. They should not be overused, however. Many defects closed by Limberg flaps could have been closed directly. The possibility of direct closure should not be excluded in order to exercise surgical bravado.

'V'to 'Y' advancement flap This flap makes use of excess tissue in the donor site.

Rhomboid (Limberg) flap (Fig. 66.17)

This reconstructionis nothing more than a transposition flap based on geometric principles. The flap is designed after the defect is converted into a rhomboid with 60" and 120" angles. In all cases, the flap is designed by extending the short diagonal and transposing into the defect. Four flaps are available, as shown in Fig. 66.18. Choice of flap depends on where the donor defect will end up, and more particularly whether hair-bearing skin will be moved into a non-hairy area. These flaps can be

Fig. 66.15 The donor defect from this flap lies in a convenient crease.

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Fig. 66.17 For every defect there are four possible rhomboid flaps. Care should be taken not to distort hair-bearing areas.

Following tumour excision, a ‘V’-shaped cut is made adjacent to it andthe ‘V’ is advanced on a subcutaneous pedicle into the defect, which is then closed as a ‘Y’. A common error is to design these flaps too small and to be overambitious about theamount of advancement

which can be obtained. It is only with experience that the pedicle can be narrowed sufficiently to produce good advancement (Figs 66.19 and 66.20). This flap is useful, as described by Herbertand Degeus (1975). Again, caremust be taken to avoid

Facial Reconstruction with Local Cutaneous Flaps

4%5

limb of the ‘ 2 3 7 - to lie irr the crease-in Fig. 66.22, in the nasolabial crease. It is helpful, especially when transposing flaps over convex surfaces, to elevate one of the triangular flaps and check the design of the second flap before incision, in order to confirm that the flaps will interdigitate correctly. See Fig. 66.23 for lip and check scars.

Fig. 66.18 In a classic rhomboid defect the angles are as shown. This can be varied with experience.

obliterating the nose-cheek junction, thereby obliterating the interface between two aesthetic units. Z-plasty

Z-plasty involves transposing two or more triangular flaps. Its main use involves the management of contractures or therevision of facial scars. The latter procedure should not be undertaken lightly, since all scarsare permanent and revised wounds may become infected, exhibit hypertrophy, or both. This has been the subject of much recent litigation. The classic Z-plasty has some use in the contracted scar, provided there is enough lateral laxity to incorporate more tissue into the wound.Typically the limbs are equal in length and the angle should be 60” to obtain maximum length. The contractual diagonalalways ends up at right angles to its original orientation. In Fig. 66.21, a Z-plasty has been transposed to correct a cicatricial ectropion. Insevere scarring, fullthickness correction of the lid is required. Similarly, a scar running across a natural crease line looks obvious and can be resited to allow the common

Fig. 66.19 Following undermining the ‘ V’ flap is ad7ranced leaving a defect. When the defect is closed a ‘Y’shape is obtained. I

It is accepted practice to commence closure with suture of the donor defect. At this stage, the success or failure of the flap design will be immediately apparent. 1 Suture material should be non-absorbable monofilament 5/0 or 610 (e.g. nylon, Prolene). Braided material, such as silk, is generally best avoided, as it is prone toleaving suture marks. Itdoes, however, have its advocates and does not ‘cheese-wire’ through thin skin like nylon or Prolene. This can be useful particularly in thin eyelid skin, but, if used, silk sutures must be removed early. Subcutaneousabsorbable (e.g. Vicryl, PDS, catgut) material may be used to decrease tension on the external sutures. Itis the authors’impression that excessive subcutaneous Vicryl causes problemswith wound healing and the senior author no longer uses this suture on the face. Manufacturers’ claims for time to absorption are not always borne out in skin if there is a poor blood supply. Unfortunately, the available needles for catgut sutures have not been updated by the manufacturers at the time of writing. 2 As a general rule, removal of sutures on the face should be between day 5 and day 7’ postoperatively. However, it shouldbe kept in mindthat collagen is only at approximately 30% strength by this time, and some patients with poor wound healing may require delayed removal. When sutures are removed, they should be cut and pulled towardsthewoundratherthanaway, in order to prevent dehiscence. After removal of sutures, supporting the wound with tape (e.g. Micropore) for a

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Chapter 66

l

L

l

Fig. 66.20 (see Fig. 66.19).

few weeks is a good idea to help improve healing and prevent dehiscence. Patients are instructedto moisturise, massage and wash their wounds early in the recovery phase. Drains and dressings

Fig. 66.21 Z-plasty can be useful to lengthen scars as in cicatricial ectropion.

These are used to prevent haematoma but are not always necessary. In large flaps, suction can help to keep raw surfaces together and occasionally dressings help in thisregard.Itshould be remembered, however, that dressings can detract from flap monitoring and indeed canproduce ischaemia by pressing on the flap base. Haemostasis must be meticulous in the head and neck,

,

Facial ~ ~ c o n ~ t r u c twith i o n LocalCutaneous

Flaps

487

Fig. 66.23 Post-traumatic or congenital shortening of the philtrum can be improved by Z-plasty.

and bipolardiathermy cautery.

allows’ specific and accurate

Complications Nerve damage

This most commonlyaffects the temporal and mandibular branches of the facial nerve, as well as the supraorbital and supratrochlear nerves. In the face of increasing litigation, patients should be warned about this. Haematoma

This can be avoided with the measures outlined above. It occasionally occurswhenpatientsstrain, stoop or vomit during recovery. If substantial, formal evacuation rnay be required. Infection

This is rare and usually follows haematoma formation. If cellulitis is present, antibiotics are prescribed. Abscess formation requires formal drainage.

Incomplete excision

If a flap has been used in reconstruction, it rnay mask tumour recurrence in the event-of inadequateclearance. It is sometimes necessary to sacrifice part or all of the reconstruction in order- to obtain. proper histology. Frozen section can be useful but is not infallible. Hypertrophic or.keloid scarring

This is a risk in all surgery. Black people and patients with blonde or red hair are at particular risk. This must be explained preoperatively. The mainstay of treatment is non-surgical, including intralesional steroid, steroid tape and vigorous m.assage. Oedema

Many circular flaps-become .swollen or ‘pincushioned’. This results from inadequate venous drainage or excessive scar formation and is more common in superiorly based flaps. It is diffitcult to treat and is unsightly.

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References Gibson T (1977) In: Converse Reconstructive Plastic Surgery,Vol. 1, 2nd edn. Philadelphia, W.B. Saunders, pp. 69-77. Herbert DC & Degeus J (1975)Nasolabial subcutaneous pedicle flap. Br. J,Plast. Surg. 28, 90-6. McGregor IA & Jackson IT (1972) The groinflap. BY.J.Pfast. Surg. 25, 3-16. McGregor IA & McGregor F (1986) Cancer of the Face artd Mouth. Edinburgh, Churchill Livingstone.

McGregor IA & McGregor AD (1995) Fundamental Techniques of Plastic Surgery, 9th edn. Edinburgh, Churchill Livingstone. McKay W, Morris R & Mushlin P (1987) Sodium bicarbonate attenuatespain on skininfiltrationwithlidocaine,with orwithout epinephrine, Anaesth. Analg. 66, 572-4. Mustard6 JC (1980)Repair andReconstruction in the Orbital Region, 2nd edn. Edinburgh, Churchill Livingstone. Smith JW & Sherrell JA (eds)(1991) Grab6 alzd Smith's Plastic Surgery, 4th edn. London, Little Brown.

Prin”ciplesof Head and Neck Reconstruction TIMOTHY E.E. GOODACRE

fensive approach in raising pectoralis major flaps) can conserve these methods for the frequentoccasions when Perhaps the commonest errors encountered in the recon- reoperation is necessary to manage recurrent disease. struction of defects in the head and neck region result from a failure to recognise one or other of the basic Conservation of vital structures principles of plastic techniques. It is therefore appropriateto discuss these principles first and foremost.This While tissue should never be conserved if such amawill enableanysurgeon to utilise correctly theplethora noeuvre compromises oncological clearance of disease, of available reconstructive techniques; a full description the preservation of a large vein for microsurgical repair of such methods requires a ‘cookbook’ approach which or of a nerve for functional restoration can improve the would fill a textbook in its own right. A limited descripreconstructive effort considerably. tion of techniques, restricted to those most frequently used, will be given at the end of this chapter. Recognition of the uniqueness of structures

introduction

Basic principles of plastic techniques Planning the reconstructionof defects

Planning the method of reconstruction should begin at thesame time asthe initial treatmentprotocol is outlined. The author does not support the frequently recommended concept that the resection of head and neck malignancy should be undertaken without heed to the reconstructive requirements of the ensuing defect. Three specificillustrate areas this. Planning resection incisions to avoid the sacrifice of potential reconstructions

Although not often used asprimaryreconstructions,subtle scalp flaps (based on the superficial temporal vessels), forehead flaps (anterior branch of superficial temporal), cervicofacial flaps (wide base, based on perforating branch of the facial vessels) and deltopectoral flaps are all useful salvage options.Forethought(suchasthe de489

Many tissues have such a unique nature that adequate reconstruction is rarely possible. These would include the lip margin,eyelid, alar crease and nasal lining. Thus, for example, a totallower lipkhin reconstruction will be vastly better reconstructed if the thin lip margin can be preserved to set on to a de-epithelialised flap border. The alternative of vermilion reconstruction from buccal mucosa or tongue is invariably a poor substitute. Likewise, a nasal alar tumour or nasolabial tumour that can be excised leaving thealar crease untransgressed will prospect enhance the of an improved long-term cosmetic outcome. That adequate tumour resection is of first importance goes without saying. However,the thoughtful surgeon should find little difficulty in constructing the mental ‘Chinese walls’ necessary to take reconstructive elements intoaccountwhen dealing withtheprimary disease. Restore like with like

Where possible, tissue defects should always be recon-

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structed with similar material. This will often involve a sharing of the residual element rather than importing a distant substitute. Thuslarge defects of the lower lip will be best managed by forms of upper lip rotation, and Abbi flap switches from the lower lip to restore upper defects. Only rarely will the resection involve greater than 60% of the total lip circumference and necessitate the difficult use of distant material. This principle applies not only toother privileged areas such as the eyelids, nose and ears, but also to such cosmetic considerations as colour match, tissue thickness and pliability, and hair-bearing nature. Thepersistence of the forehead flap as the ‘gold standard’ for total and subtotal nasalreconstruction(enhanced by prior tissue expansion) reflects this value of tissue which has similar texture and colour to thatwhich it is being used to restore. It is important to recognise that the boundaries for qualitativeimprovement in reconstruction have not been reached. Thusthe search formoresatisfactory functional tissue for intra-oral reconstruction continues, with authors in the early 1990s describing the use of jejunum and colon for such purposes. The endoscopic harvesting of such tissue for reconstructive purposes has only just begun, andfurther developments can be expected. Changing value of the ‘reconstructive ladder’

The history of reconstructive surgery has stressed the use of the simplest techniques first (from conservative management, via primary closure, tografts),holding more invasive and complex techniques in reserve for problem cases or salvage (local, thenpedicled flaps, with free vascularised tissue transfer at the apex of the ladder). Contemporarypractice in many areas of the body has shownthis to be, quite simply, an incorrect concept. If a composite free flap is likely to prove the best functional and cosmetic reconstruction for the patient, then it should always be the first choice. Such techniques are now commonplace, and there should be few occasions in which a patient is condemned to the staged, cosmetically, inferior, pedicled flap following major head and neck resections. Likewise, following severe facial injury, the enhanced blood supply of a well-vascularised flap over a radically debrided wound canspeed recovery and rehabilitation, which wouldoften be delayed if the wound is managed conservatively or with crude grafts. Adequate debridement is often only undertaken by surgeons confident that good reconstructive techniques are at hand. It is for this reason that wound debridement

should be delegated to the most senior member of the surgical team, as recommended by Trueta over 50 years ago (Trueta, 1946). Respect the functional role of the area

A frequent temptation. in reconstructive planning is to concentrate upon the externalcosmetic appearance of a structure at the expense of its functional nature. Thusanasalreconstruction thatattempts simply to restoretheexternalcontours and form of the nose, without lining a passage for air that does not contract, will inevitably fail both aesthetically and in the production of adverse symptomswith time. Similarly, a dynamic structure such as the lip might look well reconstructed with a sheet of flap tissue supported by a static fascial sling. However, such an inanimate creation will be likely to deteriorate, with fibrous contracture, intoafunctionally disabling and obstructing element that is of little overall benefit to the patient’s quality of life. Reconstructionsshouldtherefore aim to restoreas much of the functionof the area aspossible. An example of where functionalrestoration may not be feasible would be atotal glossectomy, in which atotal free vascularised myocutaneous tongue reconstructionis not possible. The functional element of the mouth as a conduit for food should then be restored as a priority. For a tongue, this might mean converting the floor of the mouth into a funnel together withacricopharyngeal myotomy. Reconstruct in cosmetic units (Fig. 67.1)

The subdivision of facial structures into cosmetic units has been a helpful reconstructive concept. The nose is divided into a sequence of adjacent rings, the lips into threeupper lip elements (bounded by thenasolabial folds and philtra1 ridges) and twolower lip elements, the cheeks as one unit each, and so forth. When a resection or injury involves morethanone of these areas,the optimal reconstruction will usually involve dealing with each unit separately. Thus a defect involving the lateral alar crease might impinge upon the lateralnasal unit, the lateral upper lip unit and even the cheek unit. A refined reconstruction of such a defect might involve an Abbi switch flap for the lip element, a bilobed or mitre flap for thenasal element, and a rotation flap for the cheek. This will leave a more cosmetically acceptable result than a large single distant flap placed across all three areas, which will resemble a shapeless ‘patch’ for ever more.

Principles of Head and Neck Reconstruction

Fig. 67.1 Important aesthetic subunits the face.

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If

Anticipate the consequences of healing

Restore bony architecture accurately

Some of themost elegant reconstructive effortsare ruinedinthe early weeks of healing by thenatural process of scar contracture. This may cause an unlined cutaneous flap to shrink and curlup, or an intra-oral or pharyngeal anastomosis to stricture. An awareness of this in planning will involve the lining of flaps, interposition of scar-lengthening techniques fromtheoutset and use of larger, healthy areas of non-traumatised or non-disease-involved skin for plastic repair. The effects of prior radiotherapy upon tissue healing are well understood. These should also be taken into careful account when reconstructionis planned, particularly where local tissue is to be used.

The final result of a head and neck reconstruction is critically dependent upon the quality of the restoration of the bone framework. No amount of manipulation of thesoft tissues will adequatelycorrecta significant defect in thecontour of themandible, midface or cranium.Theoptimal time to restorethe bone contour is at theprimaryreconstruction or fixation of injury.Theproblemsencountered in attempting secondary reconstruction of defects in which the soft tissues have contracted and of fibroses around an inadequatelyrestoredframework have been well documented. The trendtowards immediate, accurate and painstaking fixationof complex craniomaxillofacial injuries has been driven by the great difficulty in achieving good results from late correction of enophthalmos and orbital dystopia. Likewise, immediate mandibular reconstructionwithcompositeosseocutaneous freetissue transfers has enabled excellent functional restoration of the mouth following tumour resection or traumatic loss.

Cover vital structures with fulbthickness, well-vascularised tissue

Vital areas, such as bone reconstructions and neurovascular anastomoses, frequently become a source of problems because they are inadequately covered by healthy tissue. The relative ease with which large elements of skin and muscle can nowbe moved around the body should make thesight of a tightly closed head and neck defect with inadequate skin quality a thing of the past. All neurovascular structures, tendons and bone should be so covered. The ability of well-vascularised muscle (inparticular)torestoreprecarious tissues to health is remarkable, and probably underutilised in clinical practice.

Attention to detail

Reconstructive surgery requires attention todetail in the precise use of techniques and in the accurate restoration of anatomical elements. Thus with free tissue transfer, close attention should be paid to the siting and ultimate lie of the vascular pedicle, as well as many other factors which might prejudice flap survival. The successful use of even minor local skin flaps often depends upon the

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precise planning of the arc of flap movement and careful judgement in cutting the flap as far as possible without interfering with the blood supply of the most critical element. Minor aspects of anatomical restoration, such as the lip or eyelid margin, can have dramatic results on the final appearance and subsequent patient satisfaction. A little additional time spent carefully closing theskin aftera long head and neck procedure is usually rewarded substantially in time.

Reconstruction of specific areas Nose

Total rhinectomy

Skin for nasal reconstruction is best obtained from the forehead; fears of the cosmetic consequence at the donor site are usually unfounded, and the quality of reconstruction more than outweighs the use of other donor areas. The skin used for reconstruction canbe fashioned on the forehead prior to movement to enable accurate restoration of the columella and lateral alae. Tissue expansion of theforeheadskin assists closure of the donor site without resort toskin grafting. The flap skin, supplied by blood from the supratrochlear vessels, can be rotated on tothe nasal profile from an oblique donor site if the forehead is high enough (Fig. 67.2a). Alternatively, more tissue can be droppedfurtherwith less tension if the Converse ‘scalping flap’ technique is employed. Illustrated in Fig. 67.213, this technique involves mobilising the element of forehead skin to be used for the new nose on the remaining forehead (and scalp if necessary) in such a way that the skin flap unwinds and allows the nasal element to be dropped into position. This inevitably requires a larger early skin graft to cover the scalp deformity, which can be partially excised when the scalp element of the flap is divided and returned. The nasal skin reconstruction should be adequately lined to prevent contracture. The best option for this in most cases is to turn over two broadly based flaps from the lateral nasal margin, which do not have to be very long. If the extent of the nasal skin loss (excision) precludes such flaps, pedicled nasolabial flaps may be raised (superiorly based) withdirect closure of the donor sites. Pedicled buccal mucosal flaps canalso be turnedup from the upper buccal sulcus. These have the disadvantage of excessive mucousproduction and inadequate contracture prevention, however, and are usually kept in reserve. The bonykartilaginous framework should be restored in all butthemost minimal loss. Options include

costochondral cartilage (probably the best overall compromise), bone graft (split cranium, rib or iliac crest) and synthetic materials, such as Proplast. Autologous materials have a tendency to resorb, and should therefore be grafted in slight excess to compensate for this phenomenon. Onlyinextreme cases of loss of tissue fromthe midface as well as the nose is it necessary to import tissue from a distant site. If this is required, however (such as in major burn injury), free tissue transfer from the upper lateral arm or forearm avoids the need for staged procedures. If adequate recipient vessels are missing, pedicled flaps from the upper arm are probably the best option; long pedicled local flaps of postauricular skin based on the temporal vessels have a poor reliability and are hence rarely attempted today. Subtotal rhinectomy

Restoration of the bonekartilage frameworkis rarely at issue in these cases. If possible, the relevant cosmetic units should be restored with local tissue. The sliding transposition of the nasal dorsum/glabellar tissue with the GilliedRieger flap is an extremely useful method for filling large alar defects (Fig. 67.3a). Nasolabial transposition flaps can also restore similar-sized gaps (Fig. 67.313). For loss of 50% or more of the dorsum or tipof the nose, a forehead flap is again the tissue of choice. In these cases, the donor site can always be closed primarily and a good cosmetic outcome be assured. Partial nasal defects

Tip defects are reconstructed with either local bilobed flaps (Fig. 6 7 . 3 ~ )nasolabial ~ transposition or fullthickness Wolfe grafts. Of these, the bilobed flap, if applicable, will give by far the most satisfactoryresult in experienced hands, since the lateral alar groove will not be transgressed, and the skin colour and contour match will be excellent. The alar margin can be restored with some elegance by composite grafting from the pinna, although this technique requires painstaking attention to detail for success. Lips Defects of less than one-third of the length of one lip

These are best closed directly. Preliminary planning of the excision can minimise the residual scarring if the wedge resection is fashioned as an ‘M’ or ‘W’ rather than a vertical ellipse (Fig. 67.4a). Tissue loss that in-

Principles of HeadandNeckReconstruction

Fig. 67.2 Reconstruction of the nose. Forehead flap.

(b)Converse‘scalping’flap.

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volves the modiolus presents a very difficult (but fortunately rare) problem of reconstruction. Direct closure followed by secondaryreconstruction is the best optionA in such cases.

Subtotal resection of the lower lip

vast variety of flaps have been described for these common defects. They all involve useupper of the lip or nasolabial tissue, rotated in some fashion into the defect. The most commonlyused isthe Karapandzic modiSubtotal resection of upper lip fication of the Gillies fan flap, which maintains an These defects should be filledby sharingthelower-lipundisturbedmodiolus while leaving a cosmetically actissue via an Abbk lip switch procedure (Fig. 67.4b). The ceptable donor scar in the nasolabial crease line and a vascular ‘bridge’ is divided at 2 weeks afteratrial cornfully sensate and functional balanced lip (Fig. 6 7 . 4 ~ ) . pression with a vascular clamp. The flap will always appear a little tight on initial inset,

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Fig. 67.3 Subtotal rhinectorny. (a) Rieger flap. (b) Nasolabial transposition flap. (c) Bilobed flap.

but this tension leaves good a functional the scarring has matured. U

lip seal when

Total loss of the lip

Complete loss of the lower lip may be redressed by bilateral island flaps from the nasolabial regiQn (the socalled ‘steeple’ flaps), cheek advancement flaps or distant flaps from the scalp or forehead. The scalp flap has the added advantage in the male patient of bringing a hairy ‘camouflage’ element into the upper lip region, which can mask asignificant deformity. Distant transfer of forearm skin with a free flap can utilise the palmaris longus tendon as a sling from which to hang the insensate and immobile ‘curtain’.

-

LOSS

of: the ~xpvermilion .#

1

1.

Reconstruction of vermilion loss alone is mostoften required after lip-shave proceduresforpremalignant change, Mucosal advancement, using a rectangular flap of mucosa advanced while excising Burow’s triangles bilaterally, is most effective (Fig. 67.4d). Incases of total lip reconstruction, the red border can be imitated by applying a tongue-flap element on to the reconstructed lip margin. Eyelid reconstruction

Defects of the eyelid of less than 30% of the margin length can usually be closed after converting to a wedge

Principles of Head and Neck Reconstruction

Fig. 67.4 Lip reconstruction. (a) Excision wedge as ‘M’ or ‘W. (b)AbbC lip switch flap. (c) Karapandzic flap. (d) Mucosal advancement.

(

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Chapter 67

shape. Any tension can be alleviated by division of the lateralcanthal ligament to the affected lid (not both upper and lower). Larger lower-lid defects of a shallow nature can be closed using the Tripier ‘bucket-handle7 flap from theupper-lid loose skin-either full for central defects or half for marginal defects (Fig. 67.5a). Larger lower-lid defects involving all layers require two-element reconstruction. The conjunctival lining is constructed using a nasal septomucosal free graft, often best split sagittally through the cartilaginous element to reduce the bulk to approximate tothe tarsal plate thickness. The skin cover can thenbe provided either with the Tripier flap, or more commonly with a Mustard6 cheek rotation flap. This is designed high on thetemporal region to avoid downward pull; interposition of McGregor’s Z-plasty modification to the lateral orbital scar greatly improves the flap movement and inset (Fig. 67.5 b). Other techniques for upper- or lower-lid reconstruction include the eyelid ‘switch’ equivalent of the lip Abb6 flap, and superiorly based nasolabial transposition flaps.

Cheek reconstruction

Small defects of the cheek can be dealt with by methods already outlinedin the chapter onlocal flaps of the skin. Larger defects should be analysed in terms of the regions and ‘cosmetic units’ already described. Cheek rotation flaps can be designed to move either medially or laterally (Fig. 67.6a). Larger cervicofacial and cervicopectoral flaps can be advanced along the same lines to fill quite massive defects (Fig. 67.6b). These recruit skin from the lax neck and clavicular regions; any deficit left can usually be skin-graftedwith less overall cosmetic deformity than such a graftplaced directly on tothe cheek. The workhorse deltopectoral flap always requires donor-site grafting, and inset is usually followed by a second procedure 2-3 weeks later to divide the inferior pedicle. Postauricular skin caneasily be transposed in frontof the ear to fill preauricular defects. Forehead skin can also be used for cheek defects, as well asthemore common use in nasal reconstruction.

Fig. 67.5 Eyelid reconstruction. (a) Tripier flap. (b)Cheek rotation flap with McGregor’s Z-plasty.

Principles of Head and Neck Reconstrz.lction

Tongue reconstruction

Tongue defects can frequently be closed primarily with remarkably little functional deficit. Careshould be takenwiththeorientation of the closure, such that mobility is maintained. Large-defect management is based around the maintenance of speech and swallowing function, while preventing drooling and stagnation of food. Lateral hemiglossectomy defects can be resurfaced with quilted skin grafts or cheek buccal mucosal transposition flaps based posteriorly. However, the use of such local intra-oral flaps is strictly limited, and they are used most frequently today in situations which would be best managed by other techniques. Care should be taken to maintain the balance between adequate mobility of the residual tongue (which requires a good lingual sulcus) and prevention of salivary pooling (which will lead to drooling), which can result if buccinatorfunction is inadequatearoundanormaldepth lingual sulcus. Total glossectomy

Total loss of the tongue presents problems of swallowing and speech. Traditional teaching has been to convert

497

the oral cavity into an elongated ‘funnel’, thereby obviating the need for the first two stages of the swallowing mechanism. Food simply falls into thepharynx, and swallo$ving difficulties with the later stages can be improved by cricopharyngeusmyotomy.Howeverthe tongue defect is to be managed, an important precursor to the reconstruction is adequate suspension of the larynx and acricopharyngeal myotomy if swallowing problems are anticipated. Replacement of large tongue defects was accornplished with bulky myocutaneous flaps in the past. The widespread use of the pectoralis major flap for convenience is often not justified; this flap can create a constant downward pull, which tethers the floor of the mouth and restricts the vital elevation of the tongue in the early stages of swallowing. Recent workwithtongue bulk reconstruction, using free vascularised myocutaneous flaps (usually the rectus muscle), has demonstrated good restoration of both swallowing and speech mechanisms following total glossectomy. This restoration of tissue with a relatively immobile mass appears to act as a ball valve, which assists swallowing as well as closure of the oral cavity for certain speech sounds. Further work in this area is awaited.

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Floor-of-mouth reconstruction

Mandibular reconstruction

Defects of theanterior floor of themouthaloneor of the lateral aspect of the oral cavity can be elegantly reconstructed using one or two nasolabial flaps transposed into the oral cavity through the cheek wall (Fig. 67.7). If the tissue withinthe cheek is deepithelialised, division of the flap at a second stage is easily accomplished under local anaesthesia as an outpatient procedure. This method is more appropriate for the edentulous patient, as the depthof the dentate mandible and its ability to bite through a pedicle render it a more difficult technique if no gaps are present in the teeth. Larger defects are best reconstructedwithdistant tissue. Forthisend, free tissue transferhasalmost totally replaced theoutmodedforehead flap. The ideal tissue is thinand pliable, fasciocutaneous flaps being the principal method fortwo decades, with recent work into mucosal flaps progressing. The lateral arm flap, based on the profunda brachii vessels, is the most suitable small flap which does not sacrifice amajor upper limb vascular supply. It can be taken with a small element of bone if necessary, although other flaps are usually more suitable for osseocutaneous reconstruction (see later).

This large and complex field of reconstruction can only be summarised briefly in this chapter. It is an area in which accurate and careful preoperativeplanning is critical for success, particularly in the dentate patient. This is assisted by scanning (CT with three-dimensional image reconstruction if available) and by model construction, if facilities permit. Such planning enables accurate assessment of the likely bony deficit after resection and helps visualisation of the shapeof the solid reconstructionrequired to restoreasatisfactoryarch structure with good dental occlusion. If postoperative radiotherapy is planned, it is often valuable to undertake prophylactic dental extractions to prevent osteoradionecrosis; dental surgical advice should be taken on this aspect if in any doubt. The most suitable bone for reconstruction depends upon the areaexcised and the proposed treatment plan. With the adventof reliable vascularised bony free-tissue transfers, many older techniques have been made redundant. If no radiotherapy has been administered or is planned, then non-vascularised bone graft (most commonly cancellous graft placed in titaniuma mesh ‘cage’) has a role, although late problems with removing such mesh (should it become necessary) have led to a decrease in popularity of thismethod.

Fig. 67.7 Floor-of-mouth reconstruction-nasolabial flaps.

Principles of Headand Neck Reconstruction There is little role today for the unreliable free cortical graft of ribor iliac-crest bone. Likewise, the use of prosthetic rods (such as the Bowerman Conroy struts) has been discontinued, due to problems with inevitable weakening of the fixation points and frequent erosionof overlying soft tissues. A recent study investigating the role of osseointegrated strut replacement confirmed the continued superiority of free vascularised bone replacementfor all but short segmental defects in very sick patients. The three main bone-flap donor sites in common use are the fibula, iliac crest (groin flap) and radius or ulnar (forearm flap). Of these, the fibula is perhaps the most versatile, in that up to 22cmof substantial strut-shaped bone can be harvested with very little donor site morbidity. The flap canalso be harvested witha large skin paddle, the reliability if which has improved with increasing familiarity of the blood supply. The bone can be shaped with multiple osteotomies without compromising the blood supply, and is substantial enough to receive osseointegrated sockets for prosthesis carriage at a later date. The iliac-crest/groin flap is an excellent substantial bone for restoring the contour to a hemimandible, particularly if the ascending ramus is involved. A single bone strut of appropriate curvature can be fashioned from the curve of the iliac crest. The flap is raised on the deep circumflex iliac vessels, which are reliable, together with a skin paddle, if that is required. This latter skin element has the disadvantageof being overly fat in some individuals, in which case it is best excised andthe muscle overlying the bony element skin-grafted. The resultantneomandibularcontour isvery satisfactory. Both this and the fibular flap have reasonable vascular pedicles (of between 6 and 1Ocm length),but, if the pedicle is inadequate, the flap can be anastomosed to a vein-graft loop inserted intothe neck prior to reconstruction. The forearm flap can be used to transport a bone fillet of up to 12cm length. This bone should be raised carefully, since postoperative fracture of the remaining radius at the proximal osteotomy cut is not uncommon. The bone element is somewhat thin, and is usually only suitable for one (at the most two) osteotomy. It therefore makes a poor ascending ramus substitute, but can be valuable in the rapid reconstruction of simple segmental defects in the body of the mandible. It follows from the opening section of this chapter that all exposed bone and fixation metalwork should be adequately covered with well-vascularised soft tissue. A small area of non-irradiated flap bone will heal without cover, but great care should be taken with metal plates

499

and pre-existing teeth which might become exposed with radiotherapy. Postoperative care of such reconstructions requires a multidisciplinary approach, withinvolvement of experts in oral hygiene, speech, swallowing, dietarycare and othersas necessary. The use of tracheostomes is not invariable, but should be considered in the shortterm. A feeding tube is mandatory in the first week, and placement of a feeding gastrostomy (endoscopically assisted if available) canbe helpful. Trismus is not uncommon if the resection involves the condylar area,and prophylactic exercises with progressive opening should be encouraged. Postoperative radiotherapy to reconstructions in thisareacan be especially damaging, andthought should be given to joint replacement (usuallywith costochondral transfer) if severe fibrosis at the temporomandibular joint (TMJ) is anticipated. Pharyngeal defects

Management of thepharyngolarynxafter resection for cancer is beyond the scope of this chapter in all but barest outline. Methodsinvolving local tissue transposition(suchasgastricmobilisation) will not be discussed. For partial defects which cannot be closed directly without risk of stricture and for those which involve previously irradiated lumen, the ideal tissue for closure is apatch of skin or mucosa, wrappedwith wellvascularised muscle to provide a satisfactoryseal against salivary leak. The pectoralis myocutaneous flap, raised with an accurately tailored skin paddle (which may be very small) to restorethe lumen andturned over to leave the muscle surface uppermost, is the most convenient and simple option, if available. The raw muscle surface abuttingtheskin edge canthen be splitskin-grafted with ease. The initial bulkiness of such a reconstruction settles quickly, and can be reduced if the flap is raised without excess tissue by islanding the muscle on the feeding vessels with little else surrounding the pedicle. Total pharyngeal reconstruction

If circumferential defects are to be replaced with distant tissue, the choice lies between gut transfer and the fashioning of a tube from skin. Jejunum has been the most widely used gut transfer, and has the advantage of a similar luminal diameter and little in the way of sideeffects from mucus production. Colonic-segment transfer has been proposed, but the more disturbing consequences of colonic resection compared with

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jejunum have prevented widespread acceptance of this technique. Jejunum is transferred microsurgically and anastomosed in ‘reverse peristalsis’ direction to prevent the troublesome symptoms which occur when it is used in what might be expected to be the ‘correct’ direction. Thesharpcurvature of the small bowel at this level means that jejunum sits poorly in thebed if the defect is greater than 8-10 cm. Various manoeuvres have been adopted to alter the shape of the jejunal transfer in such cases. Skin tubes can be fashioned on myocutaneous flaps, although such reconstructionstend to be bulky and cumbersome and have been superseded by the use of tubedfasciocutaneous flaps, transferredas free flaps. Theradialforearm flap is used most commonly, although a wide variety of flaps have been described. This flap is ideal for defects extending from 10-1Scm, and the lack of mucosal lining or peristaltic activity does not seem to be physiologically important following the repair.Themostcommonproblemencountered is stricture formation at the lower flap/oesophageal anastomosis, and relates to the relatively narrow lumen of the thoracic oesophagus. Design of the flap to include a double Z-plastyat the lower anastomosis is believedto reduce the incidence of this side-effect. Repeated dilatation is occasionally necessary if strictureformation occurs. In design of thetubedforearm flap, careshould be taken to forma wide funnel element at theoral/ tongue-base end, such that softfood and fluids are directed smoothly into the conduit. The tube is fashionedwith two layers of closure alongthe long wall, which is then placed posteriorly to minimise the effect of any leak. With careful inset, postoperative fistula formationshould be arare occurrence. The forearm flap is a reliable transfer and has an arterial pulse the length of the flap which can be monitored easily with a Doppler probe.Venous anastomotic failure should not occur if two veins (one vena comitans and one large cutaneous vein) arerunintoone of the large neck veins. The inability to monitor venous function adequately has not been a problem in the author’s series. The long-term survival of patientswith salvage pharyngolaryngectomies is not good. The length of time spent in hospital and the morbidity incurred are therefore of great importance, and the avoidance of an abdominalwoundwith small-bowel ileus is a distinct advantage of the skin-flap repair. anagement of fistulae

Postsurgical fistulae are distressing and disabling for the

patient and can frequently be avoided by adequate resection of diseased or irradiated tissue and satisfactory, well-vascularised and overlapping tissue repair. As a rule, repairs which involve oral or pharyngeal mucosal lining should be closed with two layers which ideally do not lie in the same tissue plane. Muscle is an excellent Tiller’ and prevents the separation of tissue planes, as well as introducing asource of new vascularity to otherwise damaged tissues. Established fistulae are best excised and dealt with earlier than is sometimes recommended. The doctrine of ‘masterly inactivity’ so oftentaughtcan be a shield behind which adisappointedsurgeon seeks to hide. Although thereareundoubtedly cases in which it is advisable toawait a clear demarcation of a salivary breakdown, there are also many times when patients would benefit from the swift removal of a source of distress and embarrassment by a further reconstructive procedure. Reconstruction of the paralysed face

There is little place in contemporary surgery for a patient to be left with a disfiguring and debilitating facial palsy following operative division of the facial nerve. In the acute situation, every attempt should be made to restore continuityof the nerve with cable grafts from the sural nerve. Failing this, an immediate fascial sling, together withatemporalis muscle transfercan prevent some of the slumped oralappearance and associated drooling. The eye can be protected with tarsorraphy if necessary, although the immediate placement of a goldweight ‘lid load’ is afarmoresatisfactorylong-term solution to the palsied lid. The use of hypoglo’ssal-facial and accessory-facial nerve anastomoses is now to be deplored in anything other thanthe salvage situation. These procedures never produce a spontaneous smile and are grossly inferior to facial reanimation procedures in the younger patient. The associated loss of the XIth or XIIth cranial nerve is quite unacceptable as a reconstructive option. In the older patient, the most satisfactory method of restoring tone to the mouth is to remove the insertion of the temporalis muscle from the mandibular Coronoid process. The free end of this muscle, once disconnected, is then attached to a strip of fascia (usually harvested from the scalp), which is inset into the oral sphincter (Fig. 67.8a). This should be set in tightly to allow for some postoperativeslackening of the tissue. Alternatives to this procedure are the better-known temporalis fascia ‘turn-down’, the masseter transfer and the static fascia lata many-tailed sling insertion. In patients under theage of 55-60, when good neural

Principles of Headand Neck Reconstruction

501

Fig. 67.8 Facial-palsy correction. (a) Temporalis transfer. (b)Cross-fac:ial graft with dynamic muscle transfer.

regeneration can be reasonably anticipated and the patient is in good health, a dynamic reanimation should be considered. The first stage involves a cross-facial-nerve graftfromtheworking facial nerve to the paralysed side. Such a graft run into the cut nerve stump will not suffice, since the motor end-plates have invariably been lost in the time taken for nerve growth to occur via the graft. After asatisfactory brisk Tine1 tap response is detected in the distal end of the graft (usually after 6 months or so), a muscle is transferred to the paralysed side of the face as a free flap procedure via an extended face-lift-plane approach. This is revascularised from the facial vessels and neurotised from the cross-facial graft (Fig. 67.8b). The results for such procedurescan be remarkably good, althoughno effect is produced for the eye or upper face. The resulting spontaneous reanimated smile is immensely gratifying, however, and more than justifies the lengthy second-stage procedure.

Four versatile free flaps

Latissimus dorsi myocutaneous flap (Fig. 67.9a)

This flap can be raised as either a free flap isolated on theconstant pedicle branching off thethoracodorsal axis or as a pedicled flap islanded on the muscle insertionintothehumerus.The available skin paddle is enormous (30 X 25 cm is usually possible), and the skin element can be divided into several parts for restoration of separate defects following resection. Thus the muscle bulk can be used as “filler’ while skin paddles might be used to close the oropharynx, the nasal wall and the external skin defect. The muscle can be used alone with skin-graftcover if necessary, and theserratus anterior branch of the thoracodorsal vessels can also be raised if vascularised rib is required. This latter procedure is not ideal for bony reconstruction, however, and

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better alternativesare used morefrequentlytoday. When designing the flap, it is easiest to place the skin paddle close to the anterior free muscle border if little muscle bulk is required. More commonly,theentire muscle is raised, and the skin paddle can be placed at the most appropriate site for the reconstruction. In lifting the flap, the author’s preference is to cutthe skin paddle, and extendtheskin incision in thedirection of the posterior axillary fold. The free muscle border is identified, and the vascular pedicle falls easily into view beneaththe thickened humeralinsertion of the muscle. This insertion can be divided with ease above the site of entry of the vascular pedicle. The serratus branch of the thoracodorsalaxis is usually divided close to the latissimus pedicle, and the muscle is then free to be lifted rapidly from the chest wall. Most skin donor sites of less than 10cm can be closed primarily, avoidinga somewhat ugly skingraft in these cases. Thorough haemostasis in the donor area is vital., as is adequate drainage for several days, if the frequently encountered seroma is to be avoided. The advantagesof this flap are aninvariable anatomy, a robust blood supply and large flap vessels for easy anastomosis. A disadvantage is the need to turnthe patient slightly for flap raising.,although theexperienced operator can undertake this with minimal disturbance to the head and neck site. It is rightly considered to be one of the most dependable workhorse flaps for reconstruction throughout the body. Rectus abdominis free flap (Fig. 67.913)

This flap is usually taken as a free transfer based on the lower rectus muscle deep inferior epigastric vessels. A wide variety of flaps based on this blood supply are in current use, and the flap when pedicled can be used for breast and pelvic reconstruction. In the head and neck, it can be used asa muscle-only flap, or asa myocutaneous transfer for defects such as the tongue, maxilla and lateral oropharynx, where thinner flaps do not provide enough bulk. Like the latissimus dorsi, it has a very reliable and constant blood supply, and the ipsilateral skin paddle isvery dependable even in the obese. Multiple skin paddles can be designed, and a distinct advantage of the flap is the ability to raise it without moving the position of the patient, as it is well away from the head and neck area. The skin paddle is usually designed vertically for use in the head, and is raised with a strip of the anterior rectus sheath (which canbe reduced to a bare minimum with experience). The entire width of the rectus muscle is then harvested (no benefit has been shown to accrue

from leaving a strip of muscle once the dominant blood supply has been taken), and the inferior epigastric vascular pedicle is very obvious on the undersurface of the muscle. Once identified, the muscle can be divided above and below, in order to allow enough bulk for the procedure concerned. The vessels are then traced back to the iliac trunk easily with the help of a broad-bladed retractor.The donor site is closed primarilyinmost cases; occasionally Marlex mesh can be used to strengthen the abdominal repair if a significant amount of anterior sheath has been taken. The advantages of this flap are the ease and speed with which it can be raised (especially in the thin patient), the ability to reduce the muscle bulk much more than the latissimus dorsi flap, and the insignificant donor site and lack of donor complications. It alsohas very large vessels foranastomosis in the neck, which improves the success rate of transfer considerably. It is contraindicated if previous surgery has divided the inferior epigastric pedicle, and in the morbidly obese if skin is required. The radial forearm fasciocutaneous flap

(Fig. 6 7 . 9 ~ )

Thiswell-known flap has been responsible for transforming much of basic reconstruction following excisional surgery for small to moderate-sized lesions. It contains no muscle and therefore little bulk and adapts well to the contours of the mouth without adding deformity. It consists of a skin paddle from the forearm, which can be up to 22cmlong in the adult male, which is supplied by filmy perforating vessels from the radial artery. It is customary to perform a preoperative Allen’s test to confirm a patent ulnar vascular supply to the hand; it is, however, exceedingly rareforthis to be absent, and the test has little other than medicolegal value in the view of most operators. When raised, the skin paddle is usually outlined first, following which the distalradialartery is divided (alongwiththe venae comitantes). The flap is then lifted fromtheforearm musculature with a layer of fascia and the radial artery clearly within the tissue. Care should be taken to avoid damage to the superficial sensory branch of the radial nerve at the wrist. Thedonor site is usually skin-grafted, although small defects of up to 5cm can be primarily closed, using a sliding advancement flap of the remaining volar forearm skin. The authoralways raises the flap with a superficial cutaneous vein for drainage as well as the venae comitantes. The anatomical drainage of the forearm skin is via this route and, although not entirely necessary, it avoids any potential problems if narrow venae comitantes are found in the elderly female.

Principles of Head and Neck Reconstruction

Fig. 67.9 Free flaps. (a) Latissimus dorsi. (b)Rectus abdominis. (c) Radial forearm flap. (d) Lateral arm flap.

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Chapter 67

This flap has a completely reliable blood supply, is as robust as any other, has large vessels for anastomosis and can sustain long periods of up to 6 h ischaemia. The disadvantage of the flap is the donor site, which is ugly, as well as involving the sacrifice of a major vessel to the hand. As such, the flap should preferentially be raised in the non-dominant limb. The lateral arm free flap (Fig. 67.9d)

Thisthin, reliable, free flap from the upper arm has become the author7s flap of choice forthe small to moderate defect. It avoids the need for skin-grafting the donor site, and has fewer postoperative problems than the forearm flap with its grafted donor site. A small area of sensory loss is left in the lateral cutaneousnerve of the arm territory, but this is of negligible import in most cases. The flap can be raised under a high tourniquet or a tightly applied Esmarch bandage, and is based on the fascial perforators from the profunda brachii artery. A disadvantage is a slightly shorter pedicle than with the forearm flap, although it can be extended easily if the first branches to the deeper muscles are divided. The vascular anatomy is again reliable, and the skin paddle is soft and supple for intra-oral reconstruction.

Conclusion This chapter has attempted to deal with a subject that

rightly encompasses many textbooks in comprehensive discussions. It therefore inevitably reflects the priorities and judgements of the author’sown practice. In the area of reconstructive surgery, this must therefore relate to the surgical options which reliably ‘work’ for one given surgeon; no assurance can be made for any other practitioner, who will inevitably possess a different skill mix and set of priorities. The above selection is given, however, in good faith as a summary of a general working range of techniques. No two reconstructive procedures are ever fully alike, and the author would encourage each surgeon to develop a full repertoire of methods in order to produce the optimal reconstruction for each patient.

References and further reading Jackson IT (1985) Local Flaps in Head and Neck Reconstruction. St Louis, Mosby. Mouth. McGregor IA & McGregor FM (1986) Cancer of the Face and London, Churchill Livingstone. Soutar DS & Tiwari R (eds) (1994) Excision and Reconstruction in Head and Neck Cancer. London, Churchill Livingstone. Trueta J (1946) The Principles and Practiceof War Surgery. London, Heinemann.

Index

Page numbers in italics refer to figures, those in bold refer to tables.

AbbC: lip switch procedure 490, 493, 495

abscess Bezold’s 4 6 7 preauricular sinus excision 20 retropharyngeal space 465-7 accessory nerve see spinal accessory nerve acoustic neuroma 38, 93-105, 206, 121 audiological assessment 9 4 closure 98, 101-2, 105 complications 105 contraindications to surgical removal 9 3 craniotomy 96, 102 diagnosis 122 duralelevation 103 duralincision 100 facial nerve proximal origin loss 107 haemostasis101-2 imaging 9 4 incision 95, 96, 98, 102 internal auditory canal dissection 99-100 labyrinthectomy 9 9 mastoidectomy 9 9 middle cranial fossa approach 102-5 postoperativecare 105 preoperative management 9 4 procedure95-8,98-102 removal 100, 202 ,104-5; 2 06 retrosigmoid approach 95-8 trans~abyrinthine approach 98-102 tumour removal 96-7, 100 acromegaly 242 adenoid cystic carcinoma 2 2 6 adenoid facies 2 9 5 adenoidectomy 295-300 complications 2 9 9 contraindications 2 9 6 day-case 2 9 9 indications 2 9 5 laser 3 0 0 obstruction 2 9 5 operative technique 296-8 otitis media 2 9 5 postoperative management 2 9 9 preoperative management 2 9 6 adenoids

anatomy 2 9 7 hypertrophy 2 9 5 parapharyngeal space infection 4 6 7 adenotonsillectomy 2 9 6 adrenaline4 advancement helical flap 14 aesthesioneuroblastoma 2 3 8 age,stapedectomy 5 6 AIDS patients, cervical lymphadenopathy biopsy 409-10 airbreathing1 air cells, mastoid surgery 7 0 , 7 3 air embolism 4 1 4 air-conduction gap 4 4 air-insufflationtesting 3 9 7 airway1 fires 3 - 4 management2-3 obstruction3 total laryngectomy 370-1 severely compromised 3 space-occupying masses 301 stenotic 3 3 2 alar base reduction 187-8 alar cartilage reduction 19 1 alar crease 489, 490 alar margin restoration 4 9 2 allergic response to dressings 16 allergicrhinitis 32, 295 allergy BIPP 7 9 nasal 3 6 turbinateeffects 169 alveolar lesions 308-9 alveolar nerve, inferior 3 5 0 alveolectomy,upper 353 alveolus malignantlesions 349-56 operative technique 351-5 ameloblastoma 2 2 6 anaesthesia see general anaesthesia; local anaesthesia analgesia, perioperative 4-5 angiofibroma, juvenile 2 2 0 annulus tympanicum 4 0 anosmia, anterior craniofacial resection 2 4 1 anterior fossa repair 238-9 anterior inferior cerebellar artery 124, 22.5

anterior jugular vein 327, 328 anterior-commissurearea 375 anterior-commissuretumours 373 carcinoma in situ 3 7 4 closure after surgery 381 surgical procedure 378-9 antral wall perforation 166-7, 268 antrostomy,meatal 168 antrum anatomy 165 lavage 165 procedure166-7 repeated 168 apneoaindex 3 0 2 apnoea-hypopnoeaindex 302 apnoeic episodes 2 8 5 see also sleep apnoea, obstructive; sleep apnoea syndrome arcuateeminence 126 arterial ligation 256, 258, 259 aryepiglotticfolds 383 arytenoid adduction 3 2 0 granuloma of cartilage 3 2 4 mobility in laryngotracheal stenosis 3 3 4 vocalprocess 377 arytenoidectomy 324, 32.5 aspirinsensitivity 196 asthma 1 9 6 tympanostomy tube insertion procedure 34 atticotomy 6 7 audiogram masked speech 5 2 pure-tone see pure-tone audiogram (PTA) audiometry, speech 57, 122 audit8-9 comparative9 auditory brain-stem implant 9 8 response 9 4 auralpolyps 6 7 auricular cartilage 472 auricularprostheses80-1 benzodiazepines, upper gastrointestinal endoscopy 2 7 7 Berry’s ligament 429, 432, 433

Bezold’s abscess 467 incision 425-6 Bill’s bar 100, 101, 104, 109 indications 424 labyrinthectomy 116 operative technique 425-6 Bill’s island 99 postoperative management 426 bilobed flap 490,494 preoperative management 424 bioceramics 53 surgical procedure 426 bismuth, iodoform and paraffin paste (BIPP) bronchial anatomy 280 30-1,43 bronchial lavage 291 discharging mastoid 79 bronchoscopy 290 mastoid surgery 74 foreign bodies 290-1 myringoplasty 49-50 indications 285, 287 nasal packing 258 laser 283-4, 291 pack 28, 29 panendoscopy 275 stapedectomy 62 bronchoscopy, rigid 280-4 bleeding, pinna lesion excision 16 complications284 Bolam principle 57 indications280-1 bone graft 498, 499 procedure 28 1-3 autograft 50 Broyle’s ligament 375, 376 midfacial 216 buccal fat pad 113 bone-anchored artificial ears 80-1 buccal lesions 308-9 fixtures81, 82 bucconasal membranes, choanal atresia 204 operative technique 81-2 position 8 1 cable grafts 500 preoperative assessment 8 1 Caldwell-Luc procedure 165 single stage implantation 84 canal-wall flap, posterior 48-9 technique 84 carotid aneurysm 243 bone-anchored hearing aids 30, 80 carotid artery 398 abutment removal 83 external 258, 259, 351 audiological criteria 80 rupture in neck dissection 453 complications 83 sphenoid sinus 244, 246 erythema 83 see also internal carotid artery incision 82 carotid body tumour 414 indications 80 carotid sheath 464 inflammation 83 carotid sinus reflex 414 operative technique 8 1-2 cavernous sinus 243 position 81 cerebellar artery postoperative management 83 anterior inferior 124, 125 preoperative management 81 posterior inferior 124 screw insertion 82-3 cerebellar herniation 143 second stage 83 cerebellar infarct 105 single stage implantation 84 cerebellopontine angle bone-conduction level, stapedectomy anatomy 56 94-5 brain-stem anterior inferior cerebellar artery 124 evoked responses in vertigo 122 approaches 93-106 infarct 105 facial nerve 108, 109 branchial cysts 424-7 surgery 107 anatomy 424-5 surgical repair 114 closure 426 lesions complications426-7 diagnosis 122 Meni6re’s disease misdiagnosis 121 contraindications424 incision 425-6 neural anastomosis 114 indications 424 tumours 93 operative technique 425-6 vertigo 120 vestibulocochlear nerve 122 postoperative management 426 preoperative management 424 cerebrospinal fluid fistula endoscopic repair 254 surgical procedure 426 branchial fistula 424-7 infratemporal fossa surgery 143-4 anatomy424-5 cerebrospinal fluid leakage 249-55 closure 426 cribiform platehoof of ethmoidlsphenoid sinus 252-4 complications 427 endolymphatic sac decompression/ contraindications424 incision 425-6 drainage 134 indications 424 from pituitary fossa 243 frontal sinus 250-2 operative technique 425-6 functional endoscopic sinus surgery 202 postoperative management 426 trans-sphenoidal hypophysectomy 247 preoperative management 424 cerebrospinal fluid rhinorrhoea 249-55 surgical procedure 426 branchial sinus 424-7 closure 252, 254 complications 252, 254 anatomy424-5 closure 426 flaps 254 complications 427 mucosal 254 osteoplastic 251-2 contraindications424

free graft 249-50 incision 250-1, 252 operative technique 249-54 postoperative management 252, 254 preoperative management 249 surgical procedure 251-2, 253 surgical repair 249 cervical lymph nodes anatomy 411, 412 endoscopy 4 11 examination 410 malignant 274 management in children 411 management strategies 41 1 metastases446 neck dissection 444, 445 open biopsy indications 409-10 squamous cell carcinoma 411 see also lymph node biopsy cervicofacial flaps 496, 497 cervicopectoral flaps 496 cheek advancement flap 494 buccal mucosal transposition flap 497 reconstruction 496, 497 rotation flap 481-2, 496, 497 children cervical lymphadenopathy management 41 1 retropharyngeal space abscess 46.5 septum 181 see also laryngotracheal stenosis, paediatric choanal atresia 204-7 bilateral 204, 205 bony 205 complications 206, 207 external rhinoplasty 207 incision206-7 membranous 205 midfacial degloving 207 operative technique 204-7 oral airway maintenance 204, 205 postoperative management 206 preoperative management 204 reconstruction of choanae 207 stenting 206, 207 transnasal approach 204-6 transnasal repair 207 transpalatal correction 206-7 unilateral 204 cholesteatoma 44, 93 bone removal 70, 71 clinical assessment 66-7 closure 74 diagnosis 66 differential diagnosis 65 grafting 74 labyrinthine fistula 73 mastoid surgery 65 pearl 49, 50 surgical technique 68-74 cholesterol granuloma 93 chondrocutaneous flaps 14, l5 chondrotomy, posterior 175 chorda tympani, reflection 41 chordoma 226 chronic suppurative otitis media (CSOM) 65 bone-anchored hearing aid 80 cleft lip/palate 32 cleft palate 36 clinical trials, randomised controlled 7 CO, laser 283, 305

hypopharyngeal diverticula 347 laryngeal granuloma 324 laryngeal papillomas 324 tongue tumour resection 351 cocaine 4 cochlear implantation 85-9 complications 88-9 cultural identity 86 device extrusion 89 duration of deafness 85 educational environment 85-6 electrode array 87-8, 89 electrophysiological testing 88 failure 89 incisions 86, 87 labyrinthectomy implications 121 operative technique 86-8 postoperative management 88 preoperative management 86 rehabilitation86 cochlear nerve 123 cochlear reserve 43 cochleosaculotomy 135 cochleostomy 87 collagen, vocal-fold injection 316 common carotid artery 398 concha bullosa 194 conchal cartilage, removal for meatoplasty 26, 27 conchomeatal flap 29 congenital ear anomalies 29 continuous positive airway pressure (CPAP) obstructive sleep apnoea 304 paediatric laryngotracheal stenosis 337 Converse method of ear lobe reconstruction 14, 16 scalping flap technique 492, 493 cordectomy 373 cosmetic problems maxillectomy 23 1 osteoplastic flap 21 5 cosmetic results, lateral rhinotomy and medial maxillectomy 225 cosmetic surgery 182 counselling, rhinoplasty 183 cranial nerves jugular foramen 146 sensory supply to ear 39 craniectomy, retrosigmoid 114, 116 craniofacial resection 220 craniofacial resection, anterior 233-41 anterior fossa repair 238-9 closure 239 combined bicoronal transfacial approach 239-40 complications 241 contraindications 233 cribiform plate dissection 238 dural repair 238-9 facial flaps 236 frontal craniotomy 23 8 incision 236-7 indications 233 inferior osteotomy 237 intracranial 238 medial orbital wall exploration 237 metastases 234 midfacial degloving 240 orbital exenteration and maxillectomy 240-1 pericranial flap 239-40 postoperative care 239

preoperative management 233-4 preparation 236 procedure 236-9 relevant anatomy 234-6 resection extent 234, 235 tumour biopsy 233 tumour staging 233 Creutzfeld-Jakob disease 50, 53 cribiform plate anterior craniofacial resection 234-5 dissection 238 olfactory split 253 cricoid cartilage splits 333, 336-7 T I glottic tumours 374 cricopharyngeal inlet 270, 273 cricopharyngeal myotomy 345, 346, 347, 385 total glossectomy 497 cricopharyngeal sphincter, dilatation 347 cricopharyngeus muscle 342, 343, 346 cricothyroid membrane vertical partial laryngectomy 375, 376, 378 vocal-fold injection 316 cricothyroidectomy 371 cricothyroidostomy3 crista galli 193, 196 cross-facial nerve grafting 107, 113-14, 501 croup, recurrent 333, 337 Cushing’s disease 242 cutaneous flaps, local for facial reconstruction 476, 477, 478-87 cyanosis 285 dacrocystitis, lateral rhinotomy and medial maxillectomy 225 dacrocystorhinostomy 168 deafness age at onset 85 cholesteatoma 66, 73, 75 duration and cochlear implantation 85 external auditory canal surgery 24 mastoid surgery 73, 75 see also hearing loss, conductive; hearing loss, sensorineural deep neck space anatomy 462, 463,464 deep cervical fascia deep layer 463, 464 middle layer 462, 463, 464 superficial layer 462, 463 deep-neck-space infection 462-8 abscess 465-7 indications for surgery 464 parapharyngeal space 467-8 preoperative management 464-5 retropharyngeal space abscess 465-7 surgical principles 465 Delphian lymph node 374-5, 376 dental infection 465 dentures 308 dermoid cysts, oral cavity 309 diathermy, tongue tumour resection 35 1 diazepam premedication 13 digastric muscle 349 diplopia lateral rhinotomy and medial maxillectomy 225 vertical 21 1 diuresis 247 diverticulopexy 347

Dohlman’s operation 347 Donaldson’s line 126 Down’s syndrome 36 macroglossia 301 subglottic stenosis 286 driving, vertigo 122 dural defect, repair 238-9 ear anatomy 65-6, 472 auricular prostheses 81 conchal depth 472, 473 congenital anomalies 29 disease and stapedectomy 56 dysmorphia 471 lobe reconstruction 14, 16 see also pinna ear canal anatomy 45 closure for infratemporal fossa surgery 138-V collapsed 25 meatoplasty 28-9 fracture 29 eardrum external auditory canal surgery 23 perforated 44 ectropion 23 1 electrocautery, tonsillectomy 300 electrodessication 17 electroneurography 94 electronystagmography 94 EMLA 33,34 endocrine disorders 242 endolymphatic sac 126 decompression/drainage 133-4 endoscopy epistaxis 257 fibre-optic 272, 273 post-arterial ligation 262 sinus surgery 193-203 endotracheal tube, laryngeal examination 289 epiglottis 383 epiphora 168 lateral rhinotomy and medial maxillectomy 225 epistaxis arterial ligation 256, 258 back of nasal septumlnasopharynx 258 bipolar diathermy 257 complications 260 endoscopy 257 functional endoscopic sinus surgery 202 hereditary telangiectasia 260, 262 identification of bleeding source 256-7 indications for surgery 256 internal carotid system 262 lateral rhinotomy and medial maxillectomy 225 local control of bleeding 256, 257-8 maxillary artery 259-60 nasal pack 256, 257, 258 post-arterial ligation nasal endoscopy 262 preoperative management 256 relevant anatomy 258-62 septal abnormality 257 surgery for 256-62 within nasal fossa 257 epulides 308 Epworth sleepiness scale 302 ethmoid, trans-sphenoidal

508

Index

hypophysectomy 2 4 5 , 2 4 6 ethmoid complex anterior craniofacial resection 2 3 3 mobilisation 2 3 8 ethmoid labyrinth 2 5 3 anterior craniofacial resection 2 3 4 , 2 3 5 ethmoid resection, osteotomy 2 3 7 ethmoid sinus, roof 196 ethmoidal arteries 2 0 0 , 2 0 1 , 2 2 1 , 2 2 3 anatomy 244 blood supply to nose 2 5 8 ligation 208, 257, 261-2 ethmoidalbone,anatomy 193 ethmoidal bulla, exenteration 199-200 ethmoidal tumours 2 2 0 , 2 3 3 ethmoidectomy 199 transorbital211-12 Eustachian tube autoinflation 3 6 dysfunction 44 mastoid surgery 7 3 myringoplasty 4 9 obliteration 142, 152 patency 44 eutectic mixture of local anaesthetics see EMLA exercise tolerance, reduced 333, 337 exostoses excision from external auditory canal 21-4 meatoplasty 2 5 postauricular approach 2 2 external auditory canab’meatus 65, 66, 68, 70 anatomy 2 1 - 2 , 2 6 , 3 9 aural polyps 6 7 blind-sac closure 114, 151, 152 closure 2 3 complications 23-4 exostosis excision 2 1 - 4 incision 2 2 malignanttumours 154 middle ear approaches 4 0 , ’ 4 1 myringoplasty 49-50 operativetechnique 22-3 osteoma excision 2 1 - 4 postauricular incision 2 2 postoperativemanagement 2 3 skinelevation 4 2 skin sleeve 2 2 , 2 3 stenosis 23, 50 external carotid artery 351 blood supply to nose 2 5 8 ligation 2 5 9 external ear see ear external laryngeal nerve 4 3 0 damage in thyroid surgery 4 3 4 extraocular muscle damage 2 0 2 extubation, failed 337 eyelid goldweight 500 reconstruction 4 9 4 , 4 9 6 face cosmetic units 478, 490, 491 mask3 skin crease 483, 484 lines 478-9 facial canal 66 facial defects, tumour excision 476 facial flaps cheek rotation 481-2

design 481-5 glabellar482-3 incision lines 4 8 1 nasolabial 4 8 3 plane of dissection 476, 477 preparation480-1 rhomboid 483, 484, 485 rotation 4 7 9 transposition 4 7 9 V to Y advancement 483-5 Z-plasty 481, 482, 485, 486, 487 facial nerve 66 access 38 acoustic neuroma removal 9 7 anatomy 109-1 1 bone-anchored artificial ears 81 buccalbranches 113 cerebellopontine angle portion 109 continuity loss 107 damage in parapharyngeal space tumour surgery 460 decompression 9 3 division in petrosectomy 155, 156 electrophysiologicalassessment 108-9 exposure for infratemporal fossa surgery 139 external auditory canal surgery 2 2 extratemporal portion 109, 110, 117 facial-hypoglossal anastomosis 11 1-12, 113 graft 110, 501 cross-facial nerve 113-14 imaging 108 injury in cochlear implantation 8 9 crush-type 116 in infratemporal fossa surgery 143 integrity 4 3 internalauditory canal 109, 138 intratemporalportion 109 investigations 108-9 mastoid surgery 70-1, 72 palsy 74-5 nerve substitution 11 1-14 neuralrepair 114-17 neuromuscularsubstitution 108, 117-18 paralysis 105, 108, 441 parapharyngeal space tumour surgery 4 5 8 proximal originloss 107 repair in extratemporal course 11 7 substitutionprocedures 108 superficial conservative parotidectomy 437,438 surgery 107-1 9 anaesthesia 11 1 complications 1 19 indications 107 operative techniques 11 1-14 physiotherapy 119 postoperative care 1 18-1 9 preoperativeassessment 107-8 surgical repair cerebellopontine angle 114 internalauditorymeatus 1 1 4 intratemporalcourse114-17 symptomsinvertigo 121 temporalis transfer 11 7-1 8 total conservative parotidectomy 4 4 1 translabyrinthineexposure114-16 transmastoid-middle cranial fossa approach 116, 117 transposition

for glomus tumours of temporal bone 151, 152 in infratemporal fossa surgery 140-1 weakness after superficial conservative parotidectomy 440 facial palsy correction500-1 external auditory canal surgery 24 ossiculoplasty 55 reconstruction500-1 stapedectomy 5 8 transmastoidlabyrinthectomy 134 facial recess, mastoid surgery 7 2 facial reconstruction with local cutaneous flaps 4 7 6 , 4 7 7 , 4 7 8 - 8 7 closure 485-6 complications 4 8 7 design 481-5 indications 479-80 operative technique 480-7 preoperative management 480, 481 preparation480-1 relevant anatomy 476, 477, 478-9 rotation flaps 4 7 9 skin crease 483, 484 transposition flaps 4 7 9 facial weakness, vestibular neurectomy 133 facial-hypoglossal anastomosis 107, 108 facial-hypoglossal jump graft 112, 113 facial-hypoglossalkeeper graft 114 Fallopian canal dehiscent 3 2 neural anastomosis 114 Fanning’s law 2 fat, vocal-fold injection 316 fibrin glue, microlaryngeal surgery 323 fibularflap 4 9 9 fine-needle aspiration cytology 4 0 9 parotid gland 4 3 6 submandibular gland tumours 4 1 5 thyroid nodule 4 2 9 Fischtypeclassification 144 fistula cerebrospinal fluid 143-4, 254 chylous 4 5 3 CSF in infratemporal fossa surgery 143-4 labyrinthine 73, 121, 134 oropharyngeal 3 6 2 palatal 2 3 1 perilymph cochlearimplantation 89 vertigo 120 pharyngocutaneous 347, 394 postsurgical 500 salivary 460 superficial conservative parotidectomy 440 tracheocutaneous 331 see also branchial fistula flaps advancementhelical 14 bilateralisland 4 9 4 bilobed 490, 494 buccal mucosal transposition 4 9 7 cerebrospinal fluid rhinorrhoea 2 5 1-2, 254 chondrocutaneous 14, 1S conchomeatal 2 9 deltopectoral 4 9 6 discharging mastoid surgery 76, 77-8 fibular 4 9 9 Hong Kong 76 lateral arm free 5 0 3 , 5 0 4

latissimus dorsi myocutaneous 501-2, 503 mucosal advancement 494 myocutaneous 497 nasal reconstruction 492 nasolabial 483, 492, 494, 498 necrosis in cochlear implantation 89 pectoralis myocutaneous 499 planning 491-2 rectus abdominis free 502, 503 rotation 481-2, 496, 497 scalp 494 V to Y advancement 483-5 Z-plasty 485, 486, 487 see also facial flaps; free flap; radial forearm flap; skin flaps floor of mouth anatomy 349-5 1 lymphatic drainage 350 malignant lesions 349-56 operative technique 35 1-5 postoperative care 355 reconstruction 498 surgical complications 355 T1 and T2 tumours 351-3 T3 and T4 tumours 353-S footplate 63 forearm flap 499, 500 forehead flap 490 cheek reconstruction 496 floor of mouth reconstruction 498 lip reconstruction 494 nasal reconstruction 492, 493 foreign body removal 272 bronchoscopy 290-1 rigid 280, 283 laryngotracheobronchoscopy 289 fossa of Rosenmuller 265 biopsy 267, 275, 411 panendoscopic examination 275 fovea ethmoidalis 249 free flap 501-2, 503, 504 composite 490 grafting 4 free tissue transfer 498 Frey’s syndrome 440 frontal bone, pericranium 236 frontal craniotomy anterior craniofacial resection 238 with bicoronal incision 239-40 frontal recess mucosal flap creation 210 . patency 210 frontal sinus drainage 214 mucosa 209-1 0 frontoethmoidal complex anatomy208 closure 210, 212 complications 212 external operations 208-15 frontonasal obstruction 21 1 incision 208-9, 211 operative technique 208-10 osteoplastic flap 212-15 postoperative management 210-1 1, 212 surgical procedure 209-10, 211-12 transorbital ethmoidectomy 21 1-12 frontoethmoidectomy, external 208-1 1 frontoethmoiditis208 functional endoscopic sinus surgery see sinus surgery, functional endoscopic

functional residual capacity (FRC) 1 gastrostomy percutaneous endoscopic 143 petrosectomy 157 general anaesthesia 1-5 bloodless field 4 preauricular sinus excision 18 geniculate ganglion 116 geometric wedge excision 16 Gillies fan flap, Karapandzic modification 493,495 Gillies/Rieger flap 492, 494 gingival lesions 308-9 glabellar flaps 482-3 glomus jugulare tumour 137 glomus tumours of temporal bone 145-S3 anomalous venous drainage 145 blind-sac closure of external auditory canal151,252 classification 146 closure after surgery 150, 152-3 complications 153 contraindications145 cortical mastoidectomy 148-9 diagnosis 145-6 dissection 152 excision 152 facial nerve transposition 151, 2 52 imaging 145-6 incision 148, 150, 251 indications for surgery 145 infratemporal fossa approach 150-3 internal carotid artery distal control 149-50 exposure151-2, 253 internal jugular vein ligation 149 jugular foramen anatomy 146 multiple lesions 145 neck dissection 148 operative technique 146-53 postauricular transcanal approach 147 postoperative management 153 preoperative management 145-6 preparation for surgery 147-8 removal 150 sigmoid sinus control149 ligation 151 subtotal petrosectomy 151 transtemporal skull-base approach 148 tympanomastoid approach 147 type A 146, 147 type B 146, 147 type C 146, 147-53 type D 146, 147-53 unresectable 145 glomus tympanicum tumours 38 glossectomy349 total 351, 354-5, 490 flap 35.5 reconstruction 497 glossitis, median rhomboid 309 glossopharyngeal nerve 146 glottic tumours 373 metastasis to Delphian lymph node 375 T1374 Gluck-Sorensen incision 389, 390, 405 glue ear see otitis media, serous goals, monitoring achievement 7-8 goitre 428 compressive 429

multinodular 434 grafts facial nerve 110, 113-14, 501 skin 14, 497 great auricular nerve 110, 112 greater superficial petrosal nerve 116, 117 grommets see tympanostomy tube Guedel airway 3 haemangioma, cutaneous/subglottic 286 haemangiomatous lesions 17 haematoma cerebellar 10.5 cochlear implantation 88 facial reconstruction with local cutaneous flaps 487 intracranial105 mastoid 43 middle ear 43 neck dissection 452 orbital 247 osteoplastic flap 215 pinna lesion excision 16 pinnaplasty 475 preauricular sinus excision 20 septal163, 180 superficial conservative parotidectomy 440 Haller cell 195 head and neck reconstruction 489-94, 495, 496-502, 503, 504 attention to detail 491-2 bony architecture restoration 491 cheek 496, 497 consequences of healing 491 cosmetic units 490, 492 eyelid 494, 496 fistulae 500 floor of mouth 498 free flaps 501-2, 503, 504 functional role of area 490 lip 492-4 mandibular 498-9 nose 492, 493, 494 paralysed face 500-1 pharyngeal defects 499-500 planning 489 plastic technique principles 489-92 reconstructive ladder 490 resection incisions 489 scar formation 491 tongue 497 uniqueness of structures 489 vital structure conservation 489 coverage 49 1 hearing aid air-conduction 80 meatoplasty 29 see also bone-anchored hearing aids hearing loss acoustic neuroma 98 conductive 21, 29, 45 bilateral congenital 80 cholesteatoma66 myringoplasty SO ossiculoplasty 55 otosclerosis 56 vestibular neurectomy 132 sensorineural 30 myringoplasty 50 ossiculoplasty 55 otitis media 32

510

Index

stapedectomy 57-8 tympanostomy tube insertion 36 vestibular neurectomy 129, 132 symptomatic 32 tympanostomy tube insertion 32 vertigo 121 helium-oxygen 2 helix root, meatoplasty 26, 27-8 hemiglossectomy 351-2 defects 497 hemilaryngectomy 373, 380 reconstruction 382 hereditary telangiectasia, epistaxis 260, 262 hiatus semilunaris 193-4 HIV infection 50 cervical lymphadenopathy biopsy 409-10 Hong Kong flap 76 human papillomavirus 324 Humphrey’s circuit 33 hydrops bilateral 121 endolymphatic 120 hydroxylapatite partial ossicular replacement prosthesis 53, 54 hyoscine 5 butylbromide 277 hypertension, vertigo 121 hypertrophic scar facial reconstruction with local cutaneous flaps 487 pinnaplasty 475 contraindication 471 hypocalcaemia 434 hypoglossal nerve 3.50, 416 facial nerve graft 111-12 neck dissection 447 palsy 460 tongue base tumours 3.58 trauma351 hypoparathyroidism 434 hypopharyngeal cancer 387 larynx invasion 388 vocal cord fixation 388 hypopharyngeal diverticula 342-7 closure 347 complications 347 cricopharyngeal myotomy 345, 346 diverticulopexy 347 diverticulum inversionlsuspension 347 endoscopic procedures 347 flaps 344 incision 344 indications for surgery 342 infrahyoid muscle exposure 34.5 laser treatment 347 location of sac 346 omohyoid muscle division 344-5 operative technique 343-7 pharyngeal wall repair 346 pharyngoscopy 343-4 postoperative management 347 preoperative management 342 procedure 344-7 relevant anatomy 342-3 retropharyngeal space entry 345-6 sac resection 346 hypopharyngeal obstruction 303 hypopharynx anatomy 388,389,390 cancer laryngeal-sparing procedures 387 postoperative radiotherapy 388

radio resistance 387-8 skip lesions 388 wide submucosal disease 387 lymphatic drainage 390 resection 3 87 squamous cell carcinoma 387 tumour pyriform fossa 369 of wall 366 hypophysectomy see trans-sphenoidal hypophysectomy hypopituitarism 243 hypopnoea 302 hypothalamus compression 243 hypoxaemia laser surgery 4 open airway technique 3 prevention 1-2 hyptotympanum 72-3

IgA deficiency, maturational 32 iliac-crest/groin flap 499 incudostapedial joint, division 59, 60 incus anatomy 66 eroded long process 53 mastoid surgery 70 infants, postaural incision 41-2 inferior alveolar nerve 3.50 inferior meatal antrostomy 165-8 complications 168 contraindications 165 indications 16.5 instruments 166, 167 procedure 167 stenosis 168 technique 165-6 inferior petrosal sinus 146 inferior pharyngeal constrictor 342 inferior turbinates anatomy 169 complications from surgery 170 diathermy 171, 172 linear cautery 172 multiple submucosal outfractures 171 nasal obstruction 169 outfracturing 171 postoperative management 170 preoperative management 169 surgical reduction 169-72 trimming 169-70 partial 171 infrahyoid muscle exposure 34.5 infraorbital nerve 221, 223 infratemporal fossa bone exposure/removal 140 closure 142 complications of surgery 143-4 ear canal closure 138-9 exposure 141, 142, 143 facial nerve exposure 139 injury 143-4 transposition 140-1 flap retraction 139 incision 138, 139 jugular fossa dissection 141 labyrinthectomy 141 neck dissection 139, 140 operative technique 1 3 8 4 2 postoperative management 142-3 tumour removal 142

infratemporal fossa approaches 137-44 indications 137 preoperative management 137 rehabilitation team 137 relevant anatomy 137-8 temporal bone surgery 137 tumour imaging 137 venous angiography 137 inner ear, access 38 intermittent positive-pressure ventilation 3 internal auditory canal/meatus anatomy 94-5 approaches 93-106 closure 98, 105 dissection 99-100, 101 in middle cranial fossa approach 103-4 distance of associated structures 124 facial nerve 109, 138 surgery 119 surgical repair 114 infratemporal fossa surgery 141 middle cranial fossa approach 102-5, 124-6 petrosectomy 156 posterior wall removal 96 relationship of structures 126 removal 96, 9 7 retrolabyrinthine approach 122-3 retrosigmoid-intracanalicular approach 123 vestibular nerve 130, 132-3 internal carotid artery blood supply to nose 258 distal control 149-50 exposure for glomus tumours of temporal bone 1.51-2, 153 fossa of Rosenmuller relationship 26.5 infratemporal fossa surgery 139, 141 involvement in glomus tumours of temporal bone 14.5 oropharynx358 internal carotid system ligation 262 internal jugular vein 398 ligation 149 intersinus septum frontoethmoidal complex surgery 2 10 osteoplastic flap 213 intra-oral reconstruction 490 intracordal cysts 323, 324 intracranial structure compression 243 intratemporal course, facial nerve surgical repair 114-17 island flaps, bilateral 494 jugular bulb 146 jugular foramen anatomy 138, 146 jugular fossa dissection in infratemporal fossa surgery 141 jugular vein anterior 327, 328 internal 149, 398 Karapandzic flap 493,495 keloid scar 17, 440 facial reconstruction with local cutaneous flaps 487 pinnaplasty 475 contraindication 471 Killian incision 173-4 Killian’s dehiscence 342 KTP laser see potassium-titanylphosphate (KTP) laser

Index labyrinth damage with bone removal 123-4 labyrinthectomy acoustic neuroma 99 infratemporal fossa surgery 141 osseous 115 transmastoid 134-S labyrinthine fistula 73 labyrinthitis, post-traumatic 120 lacrimal duct stenting 239 lacrimal gland carcinoma 233 lacrimal sac 222-3 lamina papyracea 200, 202, 223 frontoethmoidal complex surgery 209 perforation 253 laryngeal carcinoma 3 83 spread to hypopharynx 387 laryngeal examination endotracheal tube 289 without endotracheal tube 289-90 laryngeal inlet examination 271-2 laryngeal mask 3 tympanostomy tube insertion 34 laryngeal nerve external 430, 434 superior 367, 368 laryngeal vessels, superior 367, 368 laryngeal-framework surgery 3 15, 18-20 3 complications 320 nasendoscopy 3 19 patient selection 3 18 phonosurgery 3 18-20 Silastic implants 318, 319-20 laryngectomy emergency 371 extended total 394-5 frontolateral partial 373 horizontal 383-6 complications 386 contraindications 383 incision 384, 38.5 indications 383 neck dissection 383-4 opening into lumen 385, 386 operative technique 384-6 postoperative procedure 386 postoperative radiation 386 preoperative management 384 repair 385-6 total 365-71 airway obstruction 370-1 closure 369-70 complications 370-1 cricothyroidectomy 371 flaps 367 imaging 366 indications 365-6 long-term effects 371 neck dissection 367-8 operative technique 367-70 pharyngeal neurectomy 369 pharyngeal repair 369, 370 postoperative management 370 preoperative management 366 pulmonary embolism 370 stomal recurrence 371 stomal stenosis 371 T4 tumours 365 tracheostome 368, 370 tracheotomy 371 tumour biopsy 366 tumour recurrence 371 voice prosthesis 369

vertical partial 373-82 anterior-commissure tumours 378-9, 381 closure 380-1 complications 382 contraindications 374 flaps 381 frontolateral procedure 377-8 hemilaryngectomy380 incision 375-6 operative technique 375-6 pathology 373-4 postoperative management 381-2 relevant anatomy 374-5 surgical indications 373-4 T1 glottic tumours 374 tumour excision 378 tumour location 374 laryngectomy tube 3 laryngofissure 334, 335-6, 373 laryngofissure-cordectomy 373, 375, 376-7 closure 380 laryngomalacia 285, 289 mimicking 290 laryngoplasty, medialisation 3 18, 320 laryngoscopy dynamic 29 1 laser 291 vocal-fold injection 316 laryngotracheal stenosis, paediatric 332-41 airway expansion 332 antibiotic prophylaxis 334 arytenoid mobility 334 augmentation 332 cartilage grafting 333 congenital 333 contraindications to surgery 333 cricoid cartilage splits 333, 336-7 degree 333-4 dilatation 332 end-to-end anastomosis 332 endoscopic assessment 333-4 extubation 332-3 grafts 338, 339, 340 interarytenoid scar 334 laryngeal reconstruction 332-3 laryngofissure 334, 335-6 laryngotracheal reconstruction 339-40 laryngotracheoplasty 338-9 laser vapourisation 332 operative technique 334-41 preoperative evaluation 333-4 relevant anatomy 334 single-stage reconstruction 337-8 and closure 340 site 334 splitting 332 stents 332, 339, 340 surgical decannulation 340-1 tracheostome closure 340 tracheostomised patients 333 laryngotracheobronchoscopy 285-91 equipment 287, 288 indications 2 87 preoperative investigations 287 technique 287, 289-90 laryngotracheoplasty 338-9 larynx anatomy 321, 366-7, 383 benign disease 320 carcinoma 373 dynamic assessment on recovery from

511

anaesthesia 290 granulomas 324 malignant disease, total laryngectomy 365 mucosal excision 321 nodules 322 paediatric 334 papillomas 323-4 polyps 322 squamous cell carcinoma 365 stroboscopy 321 visibility 303 laser 4 fire hazard 3 therapy for choana1 atresia 207 laser surgery adenoidectomy 300 bronchoscopy 291 laryngoscopy 29 1 microlaryngeal 321 microspot 323 pinna lesion excision 1 7 stapedectomyS7 tonsillectomy 300 uvulopalatoplasty 306 lateral arm free flap 503, 504 latissimus dorsi myocutaneous flap 501-2, 503 leaf granuloma 308 lenticular process, absent 54 leucoplakia 308-9 Limberg flap see rhomboid flap lingual artery 351 tongue base tumours 358 lingual nerve 350, 416 lingual thyroid 309, 422 lip defects 490 lesions 309 margin preservation 489 reconstruction 492-4, 49.5 subtotal resection 493-4 total loss 494 local anaesthesia EMLA 33,34 myringoplasty 45-6 preauricular sinus excision 18-1 9 lymph node biopsy 409-14 closure 414 complications 414 fine needle aspiration cytology 410 identification of node 414 incision 413 operative technique 412-14 postoperative management 414 preoperative management 410-1 1 preparation 413 procedure 413-14 radiology 410 relevant anatomy 41 1-12 see also cervical ~ymphadenopathy lymphatic ducts, neck dissection 447 lymphoma296 cervical lymphadenopathy biopsy 409 Lynch-Howarth frontoethmoidectomy 208-1 1 McGregor’s Z-plasty flap 496 macroglossia 301 malignant melanoma 13 mucosal220 malleus 66, 67 mastoid surgery 72

mandible, anterior dislocation 460 mandibular reconstruction 498-9 bone graft 498, 499 mandibulectomy inner-table 353 marginal 352-3, 354, 355 segmental 354 mandibulotomy anterior 353-4, 355, 363-4 lateral 363 medial, parapharyngeal space tumour surgery 457, 458-9 marginal mandibular nerve 411-12, 413, 416-17 damage during submandibular gland surgery 41 8 mastoid approaches 38-43 closure 42-3 complications 43 bowl packing 28 cavity lining 79 cortex and periosteum incision 42 discharging 76-9 complications 79 flap 76, 77-8 incision 77 meatoplasty 79 postauricular approach 79 postoperative care 79 preparation for surgery 76 mastoid surgery 65-75 bony exposure 69-70, 71 chronic aural discharge 75 clinical assessment 66-7 complications 74-5 contraindications 65 facial nerve palsy 74-5 graft 69, 74 granulation 72, 75 incision 68-9 intracranial infection 75 meatoplasty 25, 26-8 postoperative management 74 preoperative explanation 67 preoperative management 65 relevant anatomy 65-6 soft-tissue exposure 69 technique 68-74 tinnitus 75 vertigo 75 wound infection 75 mastoidectomy acoustic neuroma 95, 99 cochlear implantation 86-7 cortical 3 8 for glomus tumours of temporal bone 148-9 endolymphatic sac decompression/drainage 134 infratemporal fossa surgery 140 modified radical 67 radical 25, 67 subtotal petrosectomy 151 transmastoid labyrinthectomy 134 maxilla anatomy 227 benign pathology 226 mobilisation 229 maxillary artery ligation 259-60 maxillary sinus malignancies 226

ostium 201 pneumatisation 195 maxillary sinus lavage 165-8 complications 168 contraindications 165 indications 165 instruments 166, 167 technique 165-6 maxillary swing 226-32 closure 230, 232 complications 23 1 contraindications226 dental plate 230 incision 227-8 indications 226 maxilla mobilisation 229 operative technique 227-30 osteotomy 229, 230 postoperative management 230-1 preoperative management 226-7 soft tissue dissection 228, 229 maxillary tumour, orbital clearance 232 maxillectomy 226-32 anterior craniofacial resection 240-1 closure 229-30 complications 23 1 contraindications 226 dental plate 230 graft preparation 227 incision 227-8 indications 226 with infratemporal-fossa exploration 220 maxilla mobilisation 229 medial 220-5 operative technique 227-30 osteotomy 228-9, 230 postoperative management 230-1 preoperative management 226-7 soft tissue dissection 228, 229 meatal stenosis acquired 25 deep 29-30 minimal 25 mild 29 reoccurrence 3 1 severe 29-30 meatoplasty 25-3 1 antibiotics 31 bismuth, iodoform and paraffin paste (BIPP) pack 28, 29 cartilaginous 29 closure 28, 30-1 collapsed ear canal 28-9 complications 28 conchal cartilage removal 26, 27 deepkevere meatal stenosis 29-30 drainage 30-1 ear canal anatomy 26 granulation tissue 28, 31 incision 26-8 indications 25 mastoid surgery 25, 26-8 mild meatal stenosis 29 operative technique 26-8 postoperative management 3 1 preoperative management 25 prognosis 29-30 skin flaps 26, 27, 28, 30 sling stitch 79 mediastinitis 347 Menikre’s disease 120 misdiagnosis 121

surgical treatment 133 meningitis 89, 105 trans-sphenoidal hypophysectomy 247 mesotympanum 72-3 metastases craniofacial 234 neck dissection 446 pinna lesions 13 supraglottic cancer 386 microdrills 57 microlaryngeal surgery 320-5 arytenoidectomy 324, 325 cordotomy 322, 323 laser 321 method 322-4 patient selection 321-2 postoperative care 324-S surgical principles 321 rnicrolaryngoscopy 287, 289 microtia, auricular prostheses 80 midazolam sedation 45-6 middle cranial fossa 124-6 middle ear anat-omy 33, 38-9, 66 approaches 38-43 anaesthesia 39 closure 42-3 complications 43 endaural 41 incision 40-2 operative technique 39-43 patient positioning 39 permeatal 40-1 postaural 41-3 skin preparation 39 chronic discharge 65 cleft and malignant tumours 154 disease and stapedectomy 56 otorrhoea 36 preoperative imaging 38 preparation for myringoplasty 48 surgical anaesthesia 2 tumour spread 155 middle turbinate 193 functional endoscopic sinus surgery 201 paradoxically curved 194-5 synechiae with lateral nasal wall 202 vertical lamella preservation 209 midfacial degloving 216-19 anterior craniofacial resection 240 choana1 atresia 207 closure 218 complications 219 contraindications 216 incisions 217, 21 8 indications 216 operative technique 2 17-1 8 postoperative management 219 preoperative management 216 relevant anatomy 216, 21 7 midfacial fracture 216 mitre flap 490 mouth panendoscopic examination 274 weakness of angle 460 see also floor of mouth mucocele 415 frontoethmoidal 208, 212 frontonasal 225 lip 309 rnucociliary clearance 195 mucosal advancement flap 494

Index mucous secretion 195 mucus-retention cyst 309 Mueller manoeuvre 303 Mustardi. cheek rotation flap 496 Mustardi. technique for pinnaplasty 475 mylohyoid muscle 2.50, 349 resection 353 myocutaneous flaps 497 myringoplasty 38, 44-S1 anterior perforation 49 antibiotic prophylaxis 46 BIPP 49 cholesteatoma pearls S0 chronic aural discharge 7.5 complicationsS0 conductive hearing loss S0 contraindications44 endaural approach 46, 47-8, S0 examination 44-S external canal anatomy 4.5 packing 49-S0 stenosisS0 graft failureS0 fat 37 placing 49 incision 46, 47 indications 44 middle ear preparation 48 operative procedure 46-S0 patient positioning 46 postauricular approach 46, 47, S0 posterior canal-wall flap 48-9 postoperative management S0 preoperative management 44-S sensorineural hearing loss S0 soft tissue flap 47 suturesS0 temporalis fascia autologous graft preparation48 temporalis muscle exposure 48 transcanal S1 tympanic membrane anatomy 4.5 preparation 48 . visualisation 47 wound closure S0 myringosclerosis 36 myringotomy 34, 35, 38

N,O anaesthesia 2 Narcy test 290 nasal airflow restriction ‘301 nasal alar tumour 489 nasal bone 161-2, 163 reduction 189 nasal cartilage bent 177 dorsum 177-9 nasal cavity endoscopy 196 physiology 195 nasal crusting functional endoscopic sinus surgery 203 lateral rhinotomy and medial maxillectomy 22s trans-sphenoidal hypophysectomy 247 nasal fractures complications163-4 indications for surgery 161 366 tumours operative technique 162-3

postoperative management 163 preoperative management 161 relevant anatomy 161-2 surgical correction 161-4 nasal intubation 3 nasal malignancy, debulking 220 nasal obstruction, tympanostomy tube insertion32 nasal polyposis 196 nasal pyramid examination 161 nasal septum 161, 162, 163 abnormalities 257 cartilage graft 191 caudal displacement 176-7, 178 child 181 extendeddissection 192 fracture 181 growth centres 181 haematoma180 mobilisation 191, 192 perforation repair 173, 180-1, 216 points of fixation 192 septorhinoplasty191-2 support 18.5 wide 177 see also septal deviation; septal spurs; septodermoplasty; septoplasty nasal skin reconstruction 492 nasal spine, maxillary 18.5 nasal turbinates, diathermy 36 nasal valve area 185 widening 169 nasendoscopy flexible 303, 304 laryngeal-framework surgery 319 sleep 303, 306 nasolabial flap 483, 498 transposition 492, 494 nasolacrimal duct 193 nasopharyngeal airway 3 nasopharyngeal carcinoma 32, 220 recurrent226 nasopharyngeal stenosis 306 nasopharyngitis, deep-neck-space infection 465 nasopharyngoscopy 265-8 antegrade265-7 combined-approach 267, 268 complications268 retrograde267 sleep nasendoscopy 303 video-assisted 268 nasopharynx biopsies 27.5 endoscopic approaches 26.5-7 indirect mirror examination 26.5 nasopharyngoscopy indications 26.5 panendoscopic examination 274-S surgical anatomy 265, 266 nausea and vomiting, pinnaplasty 47.5 Nd-YAG laser 283, 284, 30.5 neck anatomy 446-7 see also deep neck space; deep-neck-space infection neck dissection cervical lymph nodes 444, 44.5 chylous fistula 453 classification 444 complications 452-3 444-53conservative

513

extended radical 444 indications 445 horizontal laryngectomy 383-4 incisions 448 indications 445 metastases 446 modified radical 444 indications 445 procedure 4.50-2, 453 occipital triangle 446 operative technique 447-52 oropharyngeal malignant lesions 359 parotid gland surgery 442 posterior cervical triangle 446 postoperative management 4.52 preoperative management 44.5”radical444-53 indications 445 procedure 448-S0 selective 444, 4.52 indications 44.5 total laryngectomy 367-8 Nelson’s syndrome 242 neonates choana1 atresia 204 tracheostomy 334 nerve damage, facial reconstruction with local cutaneous flaps 487 neural coaptation 114, 115 neurogenic tumours, maxilla 226 neuromuscular end-plate activity loss 107 non-steroidal anti-inflammatory drugs (NSAIDs)4 nose blood supply 162, 258 bonykartilaginous framework 492 flaps 494 partial nasal defects 492 reconstruction 492, 493 sensory nerves 163 tissue importation 492 obesity, snoring 303 oedema, facial reconstruction with local cutaneous flaps 487 oesophageal perforation 273 oesophageal varices 273 oesophagoscopy, panendoscopy 275 oesophagoscopy, flexible 276-9 complications 278-9 contraindications276 drugs used 277 indications276 nurses 277 passing endoscope 278 patient monitoring 277 patient preparation 276 procedure 277-8 pulmonary aspiration 278 respiratory depression 278 sedation276-7 upper GI tract perforation 278 oesophagoscopy, rigid 272-4 indications 272 operative technique 272-3 postoperative management 273 preoperative management 269, 272 relevant anatomy 269 oesophagus anatomy270 compression 428

olfactory nerve 235 olfactory neuroblastoma 238 omohyoid muscle division 344-5 ondansetron 5 open airway technique 3 opiates 277 opioids 4-5 optic chiasma 243 optic nerve anatomy 244 damage in lateral rhinotomy and medial maxillectomy 225 injury in trans-sphenoidal hypophysectomy 247 oral cavity adenoid cystic carcinoma 417 benign lesions 308-14 floor-of-mouth anatomy 3 10 lesions309-12 operative techniques 3 10-1 1 papilloma308 postoperative management 418 oral intubation 3 oral mucosa, cysts 418-19 orbital clearance, maxillary tumour 232 orbital decompression, frontoethmoidal complex surgery 21 1, 212 orbital exenteration 237 and maxillectomy 240-1 orbital haemorrhage 202 orbital tumours, malignant 233 orbital wall exploration 237 oropharyngeal obstruction 303 oropharynx anatomy 35 8 malignant lesions 357-64 anterior mandibulotomy 363-4 closure after surgery 361-2 complications of surgery 362 fistula formation 362 flaps362 incision359 indications for surgery 357 lateral mandibulotomy 363 mandible exposure 360, 362 median translingual pharyngotomy 364 neck dissection 359 operative technique 358-62 osteotomy 360 postoperative management 362 preoperative management 357-8 surgical procedure 359-61 transhyoid pharyngotomy 364 tumour excision 360, 361 orthopantornogram, mandibular invasion by tumour349 osseo-integrated implants 80-4 ossicular chain reconstruction 117 ossiculoplasty 38, 52-5 absent lenticular process 54 absent suprastructure of stapes 53-4 biomaterialsS3 complications S5 contraindications52 eroded long process of incus 53 incision 52 indications 52 operative technique 52-5 postoperative 55 preoperative assessment 52 procedure 54-5

osteoma excision from external auditory canal 2 1-4 osteoplastic flap 212, 213 removal 22 osteoplastic flap 212-1 5 closure 214 complications 2 15 contraindications213 cosmetic problems 215 incision 213 pathology recurrence 2 15 postoperative management 214 preoperative management 213 surgical procedure 213-14 osteoradionecrosis226 osteotomy double mandibular 460 external185-6 medial 186 midfacial216 ostiomeatal unit 194-S, 196 otitis externa bone-anchored hearing aids 80 chronic 29 meatoplasty 25, 29 recurrent 21 otitis media 295 acute with facial nerve palsy 32 acute suppurative 32 chronic secretory 32 recurrent acute 32 serous 32, 36 see also chronic suppurative otitis media (CSOM) otorhinorrhoea249 otorrhoea36 of middle ear 36, 37 recurrent 44 otosclerosis 56 bone-anchored hearing aids 80 outcome analysis 6 audit 8-9 complication rates 8 methods 7-8 mortality rate 8 observational studies 7-8 oxidising atmosphere, laser surgery 4 oxygen alveolar-arterial tension gradient 1 resting consumption 1 therapy 1-2 oxygenation, apnoeic 1-2 paediatric airway laryngotracheobronchoscopy 285-91 obstruction285 palatal lesions 312-14 closure 3 13 flap 313, 314 incision 3 13 mucosa sacrifice 314 operative technique 312-13 postoperative management 3 13 small313-14 palate, anatomy 312 panendoscopy 274-S bronchoscopy 275 nasopharynx examination 274-5 oesophagoscopy 275 pansinusitis 198 papilloma, inverted 220

paralytic ileus 394 paranasal sinus tumours, resection 233 parapharyngeal space 464 anatomy 455,456,457 infection 467-8 tumours clinical presentation 454 diagnosis 455 imaging 454-5 parapharyngeal space tumour surgery 454-61 anterior dislocation of mandible 460 closure 459 complications 460 contraindications454 double mandibular osteotomy 460 incision 456-7, 458, 459 indications 454 operative technique 456-9 postoperative management 460 preoperative management 454-5 transcervical approach 456-7 with medial mandibulotomy 458-9 with parotidectomy 456, 4.57-8 parathyroid glands 429-30 identification in thyroid surgery 431, 432 preservation 431-2 removal for pharyngolaryngectomy 391 resection 434 parotid gland fascia 18 fine-needle aspiration cytology 436 high grade carcinoma 441 open biopsy 436 superficial conservative parotidectomy 436-40 surgery 436-43 tumour 137 parotidectomy extended radical 442 facial nerve surgical repair 117 superficial conservative closure 440 complications 440 contraindications436 incision 437, 438 indications 436 operative technique 437-40 postoperative care 440 preoperative management 436 procedure438-40 surgical anatomy 436 total conservative 440-1 total radical 441-2 partial ossicular replacement prosthesis 53, 54 Patterson’s operation 21 1-12 pectoralis myocutaneous flap 499 PEG see gastrostomy, percutaneous endoscopic perforation 67 persistent 37 perichondritis 43 postoperative 28 perichondrium 3 84 perilymph fistula 38 peripheral neuromuscular end-organ absence 107, 117 petroclival meningioma 137 petrosal sinus, inferior 146 petrosectomy 154-8 closure 157

complications 157 facial nerve division 155, 156 flap elevation 155 incision 155 internal auditory meatus 156 operativetechnique155-7 preoperativemanagement 154 radiological assessment of tumour 154 relevant anatomy 154-5 temporal bone mobilisation 156, 157 temporalis muscle reflection 155-6 tumourspread 155 zygomaticarch 155, 2.76 pharyngeal airway3 pharyngeal constrictor, inferior 3 4 2 pharyngeal muscle tone 301 pharyngeal myotomy, surgical voice restoration 405-6 pharyngeal neurectomy 3 6 9 pharyngeal pouch 4 2 5 endoscopic diathermic treatment 3 4 7 pharyngeal reconstruction 499-500 colonic segment.$ransfer 499-500 jejunal transfer 499, 500 skintubes 500 pharyngeal repair leakage 3 7 0 pharyngeal stenosis 3 4 7 pharyngocutaneous fistula 347, 394 pharyngolaryngectomy 387-95 closure 3 9 3 - 4 complications 3 9 4 imaging 3 8 8 incision 389-90 jejunal interposition 388, 392-3 operativetechnique 389-94 postoperativemanagement 3 9 4 preoperativemanagement 388 preparation 3 8 9 procedure391-3 salvage 500 stoma 3 9 2 pharyngolaryngo-oesophagectorny 387-95, 395 oesophageal lesions 3 8 8 pharyngolaryngoscopy 269-72 complications 2 7 2 indications 2 6 9 operative technique 270 postoperative management 2 7 2 preoperative management 2 6 9 procedure 270-2 relevant anatomy 269-70 pharyngotomy lateral 363 median translingual 3 6 4 transhyoid 3 6 4 pharynx anatomy 3 9 8 parapharyngeal space infection 4 6 7 phonosurgery 3 15-20 laryngeal-framework surgery 3 15, 3 18-20 vocal-foldinjection 315-18 phrenic nerve, neck dissection 4 4 7 pinna anatomy 13, 14, 38 benign lesions 13, 14 malignantlesions 13, 14, 25 nerve supply 4 7 3 see also ear pinna lesion excision 13-14, 25, 16-17 complications 16-1 7 crescent 1 6

geometric wedge 16 laser surgery 17 postoperativemanagement 1 6 preoperativemanagement 13 reconstruction 1 6 pinnaplasty 471-5 anterior scoring method 472-4 cartilage exposure 4 7 4 incision 4 7 3 - 4 closure 4 7 4 complications 4 7 5 contraindications 4 7 1 incision 4 7 3 indications 4 7 1 Mustard6 technique 4 7 5 operative technique 4 7 2 - 4 posterior skin excision 4 7 3 postoperative management 474-5 preoperative management 471-2 scoring 4 7 4 percutaneous 4 7 5 splinting 4 7 2 pituitary adenoma, endocrine disorders 2 4 2 pituitary fossa, cerebrospinal fluid leaks 2 4 3 pituitary gland anatomy 244 compression 2 4 3 plastics 5 3 pneumocephalus, infratemporal fossa surgery 143 pneumothorax17, 4 1 4 polyposis, recurrent 2 0 8 polyps,fibroepithelial 308 postauricular flap 14, 25 postcricoid lesions, surgical procedure 391 postcricoidtumours 3 6 6 posterior inferior cerebellar artery 124 postnasal space pathology 44 poststyloidspace 4 5 5 potassium-titanylphosphate (KTP) laser 283, 305 pre-epiglotticspace 383 tumourinvasion 3 8 4 preauricularabscess 18 preauricular sinus 18, 20 preauricular sinus excision 18-20 closure19-20 complications 2 0 drainage19-20 dressing 19-20 incision 19 indications 18 operativetechniques18-20 peroperativemanagement 18 postoperative management 20 procedure 19, 20 supra-auricular approach 20 prestyloid space 4 5 5 pre-vertebralspace 4 6 4 process8-9 prochlorperazine 5 prolactinoma 2 4 2 prosthesis auricular 16 ossiculoplasty 53, 5 4 voice 369, 403-4 Blom-Singer 396, 399, 400 Provox 3 9 6 , 3 9 9 , 4 0 0 , 404 prosthetic ear, bone-anchored 3 0 psychiatric illness, rhinoplasty contraindication 183

pulmonary embolism 3 7 0 pulmonary toilet 3 2 6 pulmonary ventilation 3 2 6 pure-tone audiogram (PTA) 33, 38, 45 acousticneuroma 9 4 cochlearimplantation 8 6 frequencies 5 2 infratemporalfossaapproaches 137 mastoid surgery 7 4 ossiculoplasty 5 2 vertigo 122 pyriform fossa hypopharyngeal tumour 3 6 9 surgical procedure for lesions 391 tumours 3 6 6 questionnaires6 quinsy 2 9 5 radial forearm flap 4 9 9 , 500 fasciocutaneous 502, 503, 5 0 4 radiotherapy, meatal stenosis 2 9 randomised controlled trial 7 ranula 4 1 5 , 4 1 8 excision 3 10-1 1 marsupialisation 4 1 9 oral cavity 309-10 plunging 4 18 reconstruction ear lobe 14, 16 failure 1 7 positioning 16 rectus abdominis free flap 502, 503 recurrent laryngeal nerve 342-3, 345, 367 damage in thyroid surgery 433-4 identification in thyroid surgery 4 3 1 preservation 431-2 tracheo-oesophageal groove 4 2 9 Reinke's oedema322-3 Reinke's space, benign disease 3 2 1 retropharyngeal space 4 5 5 , 4 6 4 abscess 465-7 approaches 466-7 clinical manifestation 4 6 5 complications 4 6 5 operative technique 465-7 drainage 4 6 6 retrostyloid compartment infection 4 6 7 rhinectomy subtotal 4 9 2 , 4 9 4 total and reconstruction 4 9 2 rhinitis 198 atrophic 170 perioperativedexamethasone 173 rhinoplasty182-3, 184, 185-91 alar-basereduction187-8 bulbous tip reduction 189-90 cartilagereduction 189 closure 190 complications190-1 contraindications182-3 cosmetic 182,183,190-1 counselling 183 dehump and infracture 188-9 examination 183, 2 8 4 external for choana1 atresia 2 0 7 incision185-8 cartilage-splitting 187, 189 external 187 intercartilaginous 186, 18 8 marginal186-7, 190 osteotomy185-6,188-9

indications 3 82 investigations 183 nasal bone reduction 189 operative technique 185-90 osteotomy 185-6 patient expectations 182, 183 postoperative management 190 preoperative management 183 preparation 185 relevant anatomy 183, 185 revision 183 rhinorrhoea, cerebrospinal fluid 249-55 rhinoscopy, anterior 161 rhinosinusitis, chronic 169 rhinotomy, lateral and medial maxillectomy 220-5 closure 224 complications 225 contraindications 220 cosmetic results 225 incision 221-2 indications 220 nerves 221 osteotomy 223 postoperative management 224-5 preoperative management 220 preparation 221 procedure222-4 relevant anatomy 220-1 stents 224 vasculature 221 rhomboid flap 483,484, 485 Rieger flap 492, 494 Rinne test 66 risk stratification systems 7 rotation flap 490 saccus decompression 127 saddle deformity 177-9, 181 salivary gland surgery 415, 417 tumours 3 12 neutron treatment 41 8 see also submandibular gland surgery salivary leak, intra-oral 460 Sampter’s syndrome 196 scalp flaps 494 scaphaconchal angle 471 scar l cicatricial 28 facial reconstruction with local cutaneous flaps 487 head and neck reconstruction 491 hypertrophic 17 pinnaplasty 471, 475 Schwartz’s sign 57 sedatives, vestibular 120 semicircular canal labyrinthectomy 115 posterior 135 superior 125, 126, 132 transmastoid labyrinthectomy 134 septal deviation 173, 182 persistent 180 septal spurs 257 septodermoplasty 2 16 septoplasty 173-80 approaches 173-5 closure 179 complications 179-80 crusting 180 displaced caudal margin 176-9

dressings 179 external incision 174-5 flap elevation 175, 176 haemorrhage 179 hemitransfixion 174 indications 173 Killian incision 173-4 nasal fractures 163 preoperative management 173 preparation 173 septal perforation 180 technique 175, 176 transfixion 174 septorhinoplasty 191-2 cartilage graft 191 septum see nasal septum sialadenitis 3 11, 415 sigmoid sinus control for glomus tumours of temporal bone 149 ligation 151 Silastic, laryngeal-framework surgery 318, 3 19-20 sinonasal disease, resection of benign 216 sinus of Morgagni 383 sinus recess disease 197 sinus surgery, functional endoscopic 193-203 anaesthesia 199 Anand and Panje classification 196-8 cerebrospinal fluid leak 202 classification 196-8 complications 202 epistaxis 202 extraocular muscle damage 202 indications 195 nasal crusting 203 orbital haemorrhage 202 periorbital injury 202 postoperative management 201-2 preoperative management 195-6 radiological assessment 196, 197, 198, 199 relevant anatomy 193-5 surgical technique 199-20 1 synechiae 202 sinus tympani, mastoid surgery 72 sinus washout 36 sinusitis 32 maxillary 197 Sistrunk’s procedure see thyroglossal cyst excision skin crease 478-9, 483, 484 nasal 492 skin flaps deep meatal 23 meatoplasty 26, 27, 28, 30 skin graft pinna lesions 14 quilted 497 skull base anterior 249 lateral 138, 144 retrolabyrinthine approach 38 translabyrinthine approach 38 sleep apnoea, obstructive 296 definition 301-2 history 303 laser-assisted uvulopalatoplasty 306 medical risks 302 obesity 303

pathophysiology 301 postoperative management 305-6 uvulopalatopharyngoplasty 303 sleep apnoea syndrome 4 sleep nasendoscopy 306 sleep study 303-2 sleepiness, daytime 302, 303 snoring definition 301 heroic 302-3 laser-assisted uvulopalatoplasty 306 medical risks 302 pathophysiology 301 postoperative management 305 uvulopalatopharyngoplasty 302-3 soft tissue flap, myringoplasty 47 speaking tube 3 speech audiometry 57 vertigo 122 speech discrimination score 94 surgery for vertigo 127 speech reception threshold 94 sphenoid sinus 195 functional endoscopic sinus surgery 200 ostium 244 roof 196 trans-sphenoidal hypophysectomy 245-6 sphenopalatine artery 179, 221 spinal accessory nerve 146, 412, 413 neck dissection 447, 450, 451, 452 spine of Henle 29, 39 squamous cell carcinoma 13, 14 tonsillectomy 296 stapedectomy 56-63 access 21 alternative procedures 63 anaesthesia 5 8 antibiotic prophylaxis 58 complications 63 contraindications 56 crura fracture 60 diagnosis check 59 ear canal packing 62 ear closure 62 endaural incision 58 footplate cracks 63 footplate obliteration 63 incudostapedial joint division 59, 60 indications 56 investigations 57 laser use60-1 patient position 58 piston insertion 61, 62 platinum band crimping 61-2 postoperative management 62-3 preoperative management 57-8 risks 57-8 small-fenestra 57 surgical procedure 59-62 trephine 61 tympanomeatal incision 58, 59 vertigo 63 stapedial reflex delay, vertigo 122 stapedotomy 61 sealing 62 stapes absent suprastructure 53-4 anatomy 66 mobility 54, 59 steeple flaps 494 stents 14

choana1 atresia 2 0 6 , 2 0 9 lacrimal duct 2 3 9 laryngotracheal stenosis 3 3 2 lateral rhinotomy and medial maxillectomy 2 2 4 paediatric laryngotracheal stenosis 339, 340 sternocleidomastoid muscle, neck dissection 449,450,452 steroids, trans-sphenoidal hypophysectomy 247 stertor 2 8 5 stomal stenosis, total laryngectomy 371 stridor bronchoscopy 2 8 5 , 2 8 6 laryngotracheal stenosis 3 3 3 progressive 337 stroboscopy 3 1 5 larynx 321 subdelphiannodes 3 7 5 subglottic stenosis 286, 339 sublingualfold 3 1 0 submandibular duct 350 obstruction 4 1 5 see also Wharton’s duct submandibular gland anatomy 415-16 neoplasia 4 1 5 submandibular gland surgery 415-19 benign conditions 416-17, 418 closure417-18 complications 4 1 8 incision 4 1 6 malignant conditions 4 1 7 , 4 1 8 operative technique 416-18 postoperative management 4 1 8 preoperativemanagement 4 1 5 preparation 4 1 6 submucousresection 183 superficial musculo-aponeurotic system 183 superior laryngeal nerve 367, 368 superior laryngeal vessels 367, 368 superiorsemicircular canal 132 blue line 125, 126 supraglottic cancer, metastases 3 8 6 supraglottic tumour 3 8 3 , 3 8 5 suprameatal triangle of MacEwen 3 9 supraomohyoid neck dissection 350, 351 supratrochlear nerve 2 2 1 sural nerve 110-11, 113, 500 graft 11 3-14 sweating, gustatory 460 tackoperations 135 tarsorrhaphy 500 Teflon injection 143, 320 vocal-fold 315, 316, 317 tegmen tympani, mastoid surgery 71-2 temporalbone 39, 123 anatomy 81, 154-5 glomustumours 145-53 lateral resection 157 mobilisation in petrosectomy 156, 157 surgery 137 classification 144 temporalis fascia 118 autologous graft 4 8 bone lining 3 0 graft 4 2 temporalis transfer 107, 108, 117-18, 500, 501 temporomandibular joint 2 1 , 2 3

infratemporal fossasurgery 141 meatoplasty 2 9 third ventricle compression 2 4 3 thyroglossal cyst anatomy 420 siteincidence 421 thyroglossal cyst excision 420-3 closure 4 2 2 complications 4 2 2 incision 421, 422-3 indications 4 2 0 investigations 4 2 0 operativetechnique 420-2 postoperative management 4 2 2 preoperativemanagement 420 procedure 421, 422 thyroglossal tract 4 2 1 thyroid gland anatomy367,429-30 carcinoma 422, 434-5 isthmectomy 3 6 7 , 3 6 8 isthmus 3 2 9 lingual 309, 422 neoplasia 4 2 8 nodule 4 2 9 removal for pharyngolaryngectomy 391 total laryngectomy 367-8 thyroidsurgery 428-35 closure 432-3 complications 433-4 contraindications 4 2 8 hypocalcaemia 4 3 4 incision 4 3 0 indications 4 2 8 lobectomy 4 3 5 operative technique 430-3 postoperativemanagement 4 3 3 preoperative management 428-9 procedure 430-2 thyroid-stimulating hormone 4 3 3 thyroid-stimulating hormone-producing adenoma 2 4 2 thyroidectomy partial 4 3 3 subtotal 4 3 5 total 433, 434, 435 thyropharyngeusmuscle 342, 346 thyroplasty 143, 3 18 thyrotomy 373 thyrotoxicosis 4 2 8 thyroxine 4 3 4 tinnitus 44 mastoid surgery 7 5 stapedectomy 5 6 vertigo 12 1 tongue carcinoma354-5 of tip 3 5 2 cutting diathermy 351 lesions 309 lymphaticdrainage 3 5 0 malignant lesions 349-56 operative technique 3 5 1-5 postoperative care 355 reconstruction 4 9 0 , 4 9 7 surgical complications 3 5 5 T1 and T2 tumours 351-3 T3 and T4 tumours 353-5 tongue-flap element 4 9 4 tonsil anatomy 2 9 7 parapharyngeal space infection 467

tumourspread 357, 363 tonsillectomy analgesia 4 complications299-300 contraindications 2 9 6 electrocautery 300 indications295-6 laser 3 0 0 malignancy 2 9 6 microsurgical bipolar 3 0 0 obstructive sleep apnoea 3 0 6 operativetechnique 298-9 postoperativemanagement 2 9 9 preoperative management 2 9 9 quinsy 2 9 5 with tympanostomy tube insertion 3 6 tonsillitis chronic 2 9 6 deep-neck-space infection 4 6 5 recurrent acute 2 9 5 repeated 33 torus palatinus 312 operativetechnique 312-13 total ossicular replacement prosthesis 54 trachea anatomical relationships 3 2 7 anatomy 280, 326-7 compression 4 2 8 intubation 3, 4 palpation 328 stenosis 331 tracheal tube 4 tracheo-oesopheal puncture 396 primary 397, 398-400 relevantanatomy 398 secondary 397, 401-6 stoma 3 9 7 tracheobronchial lesions, obstructive 2 8 0 tracheobronchial tree examination 2 8 0 tracheomalacia 2 8 5 tracheostomy 3, 326-31 care 331 complications 33 1 elective 327-30 emergency 330-1 entering trachea 329 incision 3 2 8 indications 326 local anaesthesia 3 3 0 neonates 3 3 4 paediatric 334 physiological changes 3 3 1 procedure 328-30 skin flaps 328 thyroidisthmus 329 tissueplanes 328 tube insertion 329, 330-1 woundsuturing 3 3 0 trans-sphenoidalhypophysectomy 242-8 approach245-6 closure 246-7 complications247-8 contraindications 2 4 3 fluid balance 2 4 7 imaging 243-4 incision 244-5 indications 242-3 neurological observations 2 4 7 operativetechnique 244-7 postoperative management 247 preoperativemanagement 243-4 relevant anatomy 2 4 4

518

Index

steroid replacement 247 trans-septal approach 248 tumour removal 246 visual field testing 244 transfrontal sinus craniotomy 239 Tripier bucket-handle flap 496 trismus mandibular reconstruction 499 maxillary swing 231 parapharyngeal space infection 467 pterygoid muscle invasion by tumour 349 trochlea 222 tuberculosis, cervical lymphadenopathy biopsy 410 tuning fork test, stapedectomy 57 turbinectomy partial 170-1 radical 170 tympanic annulus, external auditory canal surgery 22-3 tympanic bone 39 tympanic membrane anatomy 33, 39, 45 atrophic areas 36 discharging perforated 38 meatal stenosis relationship 25 perforation 23 cochlear implantation 89 preparation for myringoplasty 48 total replacement 50 visualisation 47 tympanic neurectomy 38 tympanic plate 21, 22 tympanomeatal flap 42 posterior 40 stapedectomy 58, 59 tympanometry 33, 57 tympanoplasty, formal type 37 tympanosclerosis 56 tympanostomy tube insertion 32-7 adenoid surgery 33 alternative procedures 36-7 antibiotic prophylaxis 34, 36 complications 36 contraindications 32 examination preoperatively 33 granuloma formation 36 history 32-3 indications 32 operative procedure 34, 35, 36 operative technique 33-4, 35, 36 patient positioning 34 postoperative management 36 premature extrusion 36 preoperative management 32-3 preparation33-4 steroid cover 34 turbinate surgery 33 tympanotomy, posterior 87 uncinate process, removal 199 upper airway obstruction 326 upper gastrointestinal endoscopy 277 drugs 277 indications 276 upper gastrointestinal tract perforation 278 upper oesophageal tumours 366 uvulopalatopharyngoplasty 4, 296, 301-7 complications 306 incision 304-5 indications 302-3

laser resection 305 obstructive sleep apnoea 303 operative technique 304-5 pain control 305-6 palatal stiffening 306 postoperative management 305-6 preoperative management 303-4 reconstruction 305 resection technique 305 uvulopalatoplasty, laser-assisted 306 V to Y advancement flap 483-5 vagus nerve 146 lesions 145 neck dissection 447 Van der Hoeve’s syndrome 56 vasomotor rhinitis 32 velopharyngeal incompetence 306 ventilation 1 jet 3, 4 spontaneous3 tubes 36-7 see also intermittent positive-pressure ventilation ventilatory management 3 vermilion loss 494 reconstruction 489 see also lip vertigo 44 differential diagnosis 121 driving 122 fistula test 66 mastoid surgery 75 neuro-otological examination 122 stapedectomy 63 surgery for 120-36 anterior inferior cerebellar artery 124 conservative procedures 120, 127 destructive procedures 120, 121 endolymphatic sac decompression/ drainage 133-4 indications 120-1 middle cranial fossa approach to internal auditory canal 124-6 preoperative management 121-2 saccus decompression 127 vestibular neurectomy 127-33 surgical anatomy 122-6, 127 symptoms 121 systemic disorders 121-2 transmastoid labyrinthectomy 134 vestibular nerve 123 cutting 128, 133 section 93 vestibular neurectomy 127 closure 128, 129, 132 complications 129, 130, 133 craniotomy 130-2 CSF drainage 130 dura elevation 132 incision 128, 129, 130, 231 operative steps 128, 129, 130-1 patient preparation 127-8, 129, 130 postoperative management 128, 130, 133 retrolabyrinthine 129-30 retrosigmoid-intracanalicular 127-9 transtemporal/middle-fossa130-3 vestibular neuronitis, recurrent 120 vocal cord anterior-commissure tumours 378

bowed 318 false 383 hemilaryngectomy 380 paralysis 324 paresis 347 tumour involvement 374 vertical partial laryngectomy 377, 378, 380 vocal fold 321 arytenoidectomy 324 nodules 322 Reinke’s oedema 322 vocal fold injection 315-1 8 collagen 3 16 complications 3 18 cricothyroid membrane penetration 3 16 fat316 laryngoscopy 3 16 materials 3 15-1 6 method 3 17-1 8 operative method 3 16 patient selection 3 16 transcutaneous 3 16 vocal ligament 321 polyps 322 vocal trill 306 voice prosthesis 369, 403-4 Blom-Singer 396, 399, 400 Provox 396, 399,400,404 voice restoration, surgical 396 closure 406 complications 401, 406 contraindications 396-7 incision 402, 405 indications 396 operative technique 398-406 patient counselling 397 pharyngeal closure 400 pharyngeal myotomy 405-6 postoperative management 400-1, 406 preoperative management 397 primary 392 primary tracheo-oesophageal puncture 397, 398-400 procedure 401-5 prosthesis siting 403-4 secondary tracheo-oesopheal puncture 397,401-6 voice therapy 321 vomerine spurs 175 water entrapment 21 wax impacted 37 recurrent impaction 21 Weber test 43, 57, 66 stapedectomy 63 Weber-Fergusson incision 227 wedge incision 14 Wharton’s duct calculi 415 injury 311 see also submandibular duct wound debridement 490 Z-line 278 Z-plasty flap 485, 486, 487 Zenker’s diverticulum see hypopharyngeal diverticula zygomatic arch, division 228, 229