Microsurgery of the Skull Base E-Book

Douglas E. Mattox

• Herausgeber: Thieme
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 687

Veröffentlichungsjahr: 1988

Beschreibung

Drawing on decades of experience and wisdom, Dr. Ugo Fisch created this classic text/atlas on microsurgical procedures for the skull base. The authors have labored not to popularize skull base surgery, but to provide the details of each operation, giving surgeons the valuable information they need. Each chapter of the text discusses a specific procedure and is divided into two sections, covering both the general surgical steps of the procedure and also its application. Within each chapter you'll find: general considerations; surgical techniques; applications; tips and pratfalls; imaging scans of illustrative cases; and color plates of pre- and post-operative preparation and instrumentation. The final two chapters discuss anesthesia issues and the impact of neuroradiology on skull base surgery. All of the cases used in the book reflect actual procedures, not hypothetical situations. All neurosurgeons and otolaryngologists involved in skull base surgery will benefit from having this classic text in their professional library. It demonstrates the procedures that have proven to be both safe and reliable through the years.

Leseprobe

Ugo Fisch · Douglas Mattox

Microsurgery of the Skull Base

With Contributions by U.Aeppli and A.Valavanis

1310 Illustrations

Drawings by I. Glitsch

  Georg Thieme Verlag Stuttgart New YorkThieme Medical Publishers, Inc., New York

Addresses

Ugo Fisch, M.D.Professor and HeadENT DepartmentUniversity Hospital8091 Zürich/Switzerland

Douglas Mattox, M.D.Associate ProfessorDepartment of Otolaryngology-Head and Neck SurgeryJohns Hopkins HospitalBaltimore, MD 21205, USA

Anton Valavanis, M. D.Professor of NeuroradiologyChief, Section of NeuroradiologyUniversity Hospital8091 Zürich/Switzerland

Ulrich Aeppli, M. D.Department of AnesthesiologyUniversity Hospital8091 Zürich/Switzerland

Some of the product names, patents and registered designs referred to in this book are in fact registered trademarks or proprietary names even though specific reference to this fact is not always made in the text. Therefore, the appearance of a name without designation as proprietary is not to be construed as a representation by the publisher that it is in the public domain.

This book, including all parts thereof, is legally protected by copyright. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher’s consent, is illegal and liable to prosecution. This applies in particular to photostat reproduction, copying, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

© 1988 Georg Thieme Verlag, Rüdigerstraße 14,D-7000 Stuttgart 30, GermanyThieme Medical Publishers, Inc.381 Park Avenue South, New York, N. Y. 10016.

Typesetting: Appl, Wemding (System: Digiset 40T30)Printed in West-Germany by Appl, Wemding

ISBN 3-13-717101-6 (Georg Thieme Verlag, Stuttgart)ISBN 0-86577-288-6 (Thieme Medical Publishers, Inc., New York) eISBN 9783131775610

3  4  5  6

Library of Congress Cataloging-in-Publication Data

Fisch, Ugo.

Microsurgery of the skull base.

Includes bibliographies and index.

1. Skull base – – Surgery. 2. Microsurgery.

1. Mattox, D. II. Title. [DNLM: 1. Microsurgery.

2. Skull – – surgery. WE 705 F5278m]

RD529.F57 1988   617’.514059   88-8562

ISBN 0-86577-288-6 (U.S.)

Important Note: Medicine is an ever-changing science. Research and clinical experience are continually broadening our knowledge, in particular our knowledge of proper treatment and drug therapy. Insofar as this book mentions any dosage or application, readers may rest assured that the authors, editors and publishers have made every effort to ensure that such references are strictly in accordance with the state of knowledge at the time of production of the book. Nevertheless, every user is requested to examine carefully the manufacturer’s leaflets accompanying each drug to check on his own responsibility whether the dosage schedules recommended therein or the contraindications stated by the manufacturers differ from the statements made in the present book. Such examination is particularly important with drugs that are either rarely used or have been newly released on the market.

Preface

In ancient atlases some unexplored lands are marked “hic sunt leones”. Few dare to explore a surgical terra incognita, but the danger lies not in removing disease but in leaving it there.

Charles A. Ballance

The source of this atlas is the experience gained with 1500 skull base operations performed at the ENT Department of the University Hospital in Zurich from 1967 to 1985. Each chapter refers to a particular surgical approach and is divided in two parts; one demonstrating the general surgical steps of each procedure, the other its applications. The applications relate to individual rather than ideal cases to keep in pace with the uniqueness of surgical experience. Trifles make perfection and what happens before and after surgery is as important as the operation itself. Therefore, at the beginning of each chapter there is a detailed account of pre- and postoperative care, preparation and instrumentation as well as a short review of indications and contraindications. A section on Tips and Pitfalls at the end of each chapter recapitulates the experience gained with the corresponding surgical procedure. A collection of pre- and postoperative roentgenograms and MRI scans of illustrative cases and “color operative photographs”conclude each chapter.

Although the management of the facial nerve is a main concern throughout this book no attempt was made to concentrate the related procedures under one heading. This would have detracted from the scope of this atlas.

The technical requirements for microsurgery of the skull base may appear formidable. This applies, however, to all new surgical procedures. Charles Ballance writes in his famous book on “Surgery of the Temporal Bone”: “but difficult as the operation is, there is no justification for throwing around it a cloak of mystery as if only the elect were ever called upon to perform it”. This atlas is not an attempt to popularize skull base surgery. Its aim is to show the details of each surgical procedure so that the interested surgeon may perform it with more ease than we had in its development.

Microsurgery of the skull base is not a superspecialized surgical exercise. My professional formation was determined by three great teachers: Luzius Rüedi, John Conley and William House. Luzi transmitted the secrets of microsurgery of the ear and his passion for the essential, John the drive to overcome with rational elegance the most arduous surgical challenges of the head and neck, and Bill the determination of a pioneer looking for new surgical fields beyond the temporal bone. It was by combining the different teachings and not by superspecializing in one that I found the adequate technical background for the work at the skull base.

The desire to include the skull base into the horizon of otologic surgery originated during a six weeks visit in Los Angeles in 1967. Fascinated by William House’s innovative work and after intensive training on the cadaver, I performed the first translabyrinthine and middle fossa approaches in Zurich together with Gazi M. Yasargil at the end of that year.

It has been a great privilege to be introduced into neurosurgical technique and philosophy through Gazi’s superb microsurgical skills and through his supercritical, demanding mind. Our direct association in the operating theatre lasted for two years; the time required for each of us to learn what was needed to carry out independent but complementary work.

The approaches presented in this atlas emerged in the following years from the search for adequate ways to remove lesions situated in what was still a bony noman’s land between otology and neurosurgery. The leading principle through this evolution was to find adequate access by removing bone from the skull base rather than by elevating or retracting dura. First we modified the middle fossa approach. The temporal lobe elevation was minimized using the blue-lined superior semicircular canal as the only landmark for the internal auditory canal. The surgical access was mainly obtained by removing bone at the roof of the temporal bone, above the inner ear and was, therefore, called transtemporal, supralabyrinthine. Next was the introduction of subtotal petrosectomy. This operation, consisting of closing off the eustachian tube and exenterating all pneumatic spaces of the temporal bone, was used for the removal of various intratemporal lesions. When combined with the obliteration of the middle ear cleft and the removal of the otic capsule, subtotal petrosectomy allows removal of tumors within the posterior fossa through the complete medial wall of the temporal bone. This transotic approach has replaced the translabyrinthine route for the resection of acoustic neurinomas because it has virtually eliminated the risk of a postoperative CSF leak. Our attention then turned to the jugular foramen. Radical removal of large tumors situated in this anatomical region was precluded by the position of the fallopian canal. The solution to this surgical problem was found in the permanent anterior displacement of the facial nerve. This originated the infratemporal fossa approach type A which provides access along the intratemporal course of the internal carotid artery.

The infratemporal approaches B and C were the logical sequence in striving for anterior exposure of the lateral skull base. In combination with conventional head and neck procedures they permit en bloc removal of tumors invading the skull base from the nasopharynx and parapharyngeal space. The various techniques for petrosectomy and radical dissection of the retromandibular fossa were finally developed mainly to deal with tumors of the deep lobe of the parotid gland involving the petrous bone.

The co-author of this atlas, Douglas Mattox, joined in the preparation of these pages while spending a year of clinical fellowship with us in 1985. The material for this book was already collected but still needed to be put into proper form. Many weeks of common discussion, writing and re-writing were necessary to achieve this major task. They were for me a most rewarding experience. Douglas’s incredible working capacity, organization and critical compliance have greatly improved the quality and considerably shortened the time of gestation of our common endeavour. The association with Douglas has also closed a circle that initiated 27 years ago when I began my ENT career with a clinical fellowship at the John’s Hopkins hospital!

The recent progress made in imaging and interventional neuroradiology has greatly influenced the surgical procedures described in this atlas. The introduction of computerized tomography in our hospital in 1975 has led to precise information on the extent of invasion and of resection of a skull base lesion. But even the most modem technology remains only as good as the people who use it. We were fortunate to meet Anton Valavanis who is an exceptionally capable, inventive and industrious neuroradiologist. He has dedicated much of his energy and time to skull base problems. The imaging of illustrative cases found at the end of each chapter is based on his splendid work. I am also grateful to Anton for agreeing to write a chapter of this atlas on interventional neuroradiology. He is a master in embolizing the finest arteries and has an unmatched skill in testing the effectiveness of collateral cerebral circulation and in occluding the internal carotid artery with detachable balloons. His work has opened new vistas for the extension of skull base surgery in the region of the cavernous sinus.

Ulrich Aeppli carried out with uncommon proficiency and reliability the general anesthesia in the majority of the operations described in this book. A man of few words, it was not easy to motivate him to put his valuable experience in writing. He did it reluctantly but with great care. I am very grateful for his efforts.

This atlas reflects a subjective view of skull base surgery. The procedures shown are those that we have found adequate, reliable and safe through the years. As they cover in great part a new surgical field, a step by step presentation was preferred to a display of general surgical principles. The illustrations are a selection of drawings that I have carried out personally at the end of each operation over a period of eight years. They were made by memory and entail, therefore, simplifications and deformations of reality. The final artistic work was carried out by Ivan Glitsch. Our association reaches back more than 25 years. We have learned to communicate with each other by pencil lines rather than by words. He has the great merit to have added his invaluable professional, artistic touch to the essence of the surgical act.

The photographic documentation of pre- and postoperative preparation and instrumentation was carried out with extreme care by Jeanpierre Rüegg. We are grateful to Judith Terjek for giving her best in reproducing our collection of imaging slides, and for helping in selecting the microphotographs for the color plates.

Many other individuals have helped directly and indirectly during the preparation of this book. A number of clinical fellows came to Zurich through the years to be introduced to microsurgery of the skull base. Their stimulating participation in surgery as well as their help in reviewing clinical histories and in the research laboratory have speeded up the cristallization of the material put in these pages. Among those I would like to mention: Derald Oldring, Robert Dufour, Julian Nedzelski, Michel Rouleau, Newton Coker, Herman Jenkins, Bruce Gantz, Michael Holliday, Zheng-Min Wang, Harold Pillsbury, Navin Hiranandani, José Sanchez, Richard Wiet, Steven Burres, Stephen Wetmore, Paul Fagan, Arwind Kumar, Jeffrey Harris, Robert Dobie, Maurice Hawthorne, Jona Kronenberg, Michael Gleeson, Jacques Herzog, Lawrence Grobmann, Jack Lancer, Jin-cheng Zhao, Hassan El Sayed, Andrew Swanston, Tom Eby.

I also have to acknowledge the dedicated help of the medical staff of my department, mainly of Peter Ott, Christian Gammert, Markus Wolfensberger and Thomas Spillmann. Heidi Felix, Anita Pollak and Norbert Dillier have provided the invaluable frame supporting the work in the research laboratory.

The department nurses under the direction of Ingrid van Riesen have assured the perfect care of the operated patients. Worthy of particular mention is the superb assistance provided in the operating theatre by Kaja Burmann, Marianne Wüst and Ruth Péclard, among others.

Luitgard Wagner, Verena Tompkins and Ch. Hofmann have graciously helped to carry a great load of secretarial work during the maturation of this atlas.

Our thanks go also to Mrs. Hadler and Mr. Lehnert of Georg Thieme Verlag for contributing so much in putting this atlas in the best possible form. I am also particularly grateful to Dr. Hauff for supporting the effort involved with this atlas from the very beginning.

Finally, my deepest gratitude goes to my wife Monica and my children Marina and Jann. For many years they have gracefully tolerated an egoistic professional interest which detracted so much from our common time. Without their continuous support this book would never have come into existence.

Ugo Fisch

It did not take me long to accept the challenge of assisting Ugo Fisch in writing what he called a “monograph” on skull base surgery. Over the ensuing months that “monograph” grew to proportions neither of us predicted at the outset. This expansion was not the result of uncontrolled growth, but the natural extension of the demand for precision and detail characteristic of Ugo Fisch both as a surgeon and a teacher.

There is no doubt that I am this volume’s greatest beneficiary: the thoughts and concepts in this book are only a sampling of those that crossed between us in the hours spent in surgery, the dissection laboratory, and pouring over the drawings and text. I sincerely hope that the accuracy and clarity of the text reflects the experience and knowledge behind it.

One of the unique aspects of this book is that the cases used as examples are real; not idealized artist’s renditions. The reader will find it refreshing that not every case is easy; that things do not always go as planned. But this format leads to something more important, the strategies and approaches used to solve difficult intraoperative problems. This degree of realism is a tribute not only to superb record keeping, but also Ugo’s extensive file of hand drawn illustrations which he makes after every difficult or interesting case.

My special thanks go to Michael E. Johns, chairman Department of Otolaryngology - Head & Neck Surgery of Johns Hopkins Hospital for making my fellowship in Zürich possible.

Lastly, I too would like to thank my young family, my wife Kathrin and daughter Alison, for their tolerance and acceptance of lost weekends and vacations spent writing in the completion of this text.

Douglas E. Mattox

Contents

Chapter 1Subtotal Petrosectomy

Part 1General Considerations

Rationale, Indications and Complications

Rationale

Surgical Highlights

Indications

Contraindications

Preoperative Contaminated Wounds

Complications

Infection

Wound Healing

Preoperative Preparation

Premedication

Anesthesia

Antibiotics

Operative Site

Position of the Patient

Draping

Instrumentation

Instruments for Subtotal Petrosectomy

Postoperative Care

Dressings

Drains

Extubation

Analgesia and Antiemetics

Anti-Thromboembolic Prophylaxis

Intravenous

Suture Removal

Abdominal Wound

Leg Wound

Part 2Surgical Technique

Surgical Technique

Skin Incision

Blind Sac Closure of External Auditory Canal

Exenteration of Pneumatic Middle Ear Cleft

Obliteration of the Eustachian Tube

Obliteration of the Operative Cavity

Wound Closure

Part 3Applications

Applications of Subtotal Petrosectomy

Chronic Otitis Media

Postoperative CSF Otorrhea and/or Meningitis

Spontaneous CSF Leaks

Post-traumatic CSF Leaks

Transverse Fracture of the Petrous Pyramid

Meato-Mastoid Rerouting of the Fallopian Canal and End-to-End Anastomosis

Surgical Highlights

Meato-Mastoid Rerouting of the Fallopian Canal and Grafting

Exposure of the Facial Nerve and Hypoglosso-Facial Crossover

Ballistic Injury of the Temporal Bone

Surgical Highlights

Iatrogenic Trauma

Surgical Highlights

Gradenigo’s Syndrome

Surgical Highlights

Supralabyrinthine Cholesteatoma

Surgical Highlights

Tumors of the Temporal Bone

Selection of Approach for Epithelial Cysts of the Temporal Bone (Including Cholesteatoma)

Lesion of the Middle Ear and Mastoid

Supralabyrinthine Lesions

Infralabyrinthine Lesions

Apical Lesions

Lesions at the Foramen Lacerum

Nerve Graft Donor Sites and Graft Preparation

Greater Auricular Nerve Graft

Sural Nerve Graft

Preparation of the Nerve Graft

Part 4Tips and Pitfalls

Tips and Pitfalls

Part 5Imaging of Illustrative Cases

Imaging of Illustrative Cases

Subtotal Petrosectomy with Preservation of the Otic Capsule and Open Cavity

Subtotal Petrosectomy with Preservation of the Otic Capsule and Obliteration of the Cavity

Subtotal Petrosectomy with Removal of the Otic Capsule and Obliteration of the Cavity

Part 6Color Plates

Color Plates

Subtotal Petrosectomy with Removal of Otic Capsule for Papillary Cystadenoma

Subtotal Petrosectomy for Supralabyrinthine Cholesteatoma

Chapter 2Transotic Approach to the Cerebellopontine Angle

Part 1General Considerations

Rationale, Indications, and Complications

Rationale

Surgical Highlights

Indications

Contraindications

Size of Tumor

Infection

Complications

Facial Nerve

CSF Leak

Infection

Preoperative Preparation

Premedication

Anesthesia

Antibiotics

Operative Site

Position of the Patient

Draping

Instrumentation

Instruments for Transotic Approach

Postoperative Care

Dressings

Drains

Postoperative Care

Analgesia and Antiemetics

Anti-Thromboembolic Prophylaxis

Suture Removal

Abdominal Wound

Leg Wound

Part 2Surgical Technique

Surgical Technique

Skin Incision

Blind Sac Closure of the External Auditory Canal

Mastoid Periosteal Flap

Transection of the External Auditory Canal

Closure of the External Auditory Canal

Subtotal Petrosectomy; Exposure of Jugular Bulb and Internal Carotid Artery

Removal of the Lateral External Auditory Canal Skin

Mastoidectomy

Total Removal of the External Canal Skin

Mastoidectomy and Skeletonization of Fallopian Canal

Removal of Tympanic Bone

Obliteration of the Eustachian Tube

Exposure of Internal Auditory Canal and Posterior Fossa Dura

Tumor Removal

Wound Closure

Obliteration of the Cavity

Drains

Skin Closure

Part 3Applications

Applications of the Transotic Approach

The “Large” Acoustic Neuroma

Surgical Highlights

High Jugular Bulb in Acoustic Neuroma

Surgical Highlights

Intracranial Injury of the Facial Nerve During Transotic Removal of Acoustic Neuroma

Most Common Site of Injury of the Facial Nerve

Transotic One Stage Intracranial-Intratemporal Grafting of the Facial Nerve

Acoustic Neuroma

Surgical Highlights

Intrameatal Mucosal Cyst

Surgical Highlights

Intracranial Hemangioma

Surgical Highlights

XII-VII Crossover in the Transotic Approach

Part 4Tips and Pitfalls

Tips and Pitfalls

Part 5Imaging of Illustrative Cases

Imaging of Illustrative Cases

Acoustic Neuroma

High Jugular Bulb and Acoustic Neuroma

Other Internal Auditory Canal Lesions

Part 6Color Plates

Color Plates

Transotic Approach for Acoustic Neuroma

Transotic One-Stage Intracranial - Intratemporal Grafting of the Facial Nerve

Chapter 3Infratemporal Fossa Approach Type A

Part 1General Considerations

Rationale, Indications, and Complications

Rationale

Surgical Highlights

Indications

Contraindications

Carotid Involvement

Contralateral Vagus Lesion

Unresectable Tumor

Complications

Infection

CSF Leak

Cranial Nerve Palsy

Facial Paralysis

Tissue Ischemia and Necrosis

Cardiovascular

Pulmonary Embolus

Cerebral Edema

Preoperative Preparation

Premedication

Anesthesia

Antibiotics

Operative Site

Position of the Patient

Draping

Instrumentation

Instruments for Infratemporal Approach Type A

Postoperative Care

Dressings

Drains

Extubation

Analgesia and Antiemetics

Anti-Thromboembolic Prophylaxis

Intravenous

Suture Removal

Abdominal Wound

Leg Wound

Classification of Glomus Temporale Tumors

Class A

Class B

Class C

Class D

Part 2Surgical Technique

Surgical Technique

Skin Incision

Blind Sac Closure of the External Auditory Canal

Mastoid Periosteal Flap

Transection of External Auditory Canal

Closure of External Auditory Canal

Exposure of the Facial Nerve in the Parotid

Exposure of the Vessels and Cranial Nerves in the Neck

Subtotal Petrosectomy

Anterior Transposition of the Facial Nerve

Ligation of Sigmoid Sinus

Exposure of the Internal Carotid Artery Distal to the Tumor

Obliteration of the Eustachian Tube

Exposure of the Infratemporal Fossa

Removal of Disease

Removal of Class C1 Glomus Tumors

Tumor Removal

Reconstruction of Dura

Wound Closure

Obliteration of the Operative Cavity

Temporalis Muscle Flap

Drains

Skin Closure

Removal of Class C2 Glomus Tumors

Tumor Removal

Wound Closure

Removal of Class C3 Glomus Tumors

Tumor Removal

Wound Closure

Removal of Class C4 Glomus Tumors

Tumor Removal from the Sigmoid and Transverse Sinus

Tumor Removal from Foramen Lacerum and Cavernous Sinus

Wound Closure

Intracranial Extension of Glomus Temporale Tumors (Class De and Di)

Removal of Class Del and De2 Glomus Tumors

Removal of Class Di Glomus Tumors

Class Di1 Tumors

Class Di2 Tumors

Reconstruction of the Dura

Class Di3 Tumors

Bilateral Glomus Temporale Tumors

Ipsilateral Glomus Temporale and Glomus Caroticum Tumors

Facial Nerve Involvement by Glomus Tumors

Segmental Removal of Epineurium with Anterior Rerouting

Intratemporal - Extratemporal Nerve Graft with Anterior Transposition

Intracranial - Extratemporal Nerve Graft with Superior Temporal Rerouting

Hypoglosso-Facial Crossover

Trigemino-Facial Crossover with Nerve Grafting

Approaches for Glomus Tumors Class A and B

Class A Tumors (Glomus Tympanicum)

Class B Tumors (Glomus Hypotympanicum)

Part 3Applications and Adjunctive Procedures

Applications of Infratemporal Approach Type A

Glomus Temporale Tumors

Surgery of the Carotid Artery

Small Lacerations of the Intratemporal Carotid Artery

Large Lacerations of the Intratemporal Carotid Artery

“Aberrant” Carotid Artery

Aneurysm of the Internal Carotid Artery

Glomus Caroticum Tumors

Infralabyrinthine Cholesteatoma

Surgical Highlights

Infralabyrinthine Cholesteatoma without Extension to the Pyramid Apex

Infralabyrinthine Cholesteatoma Invading the Pyramid Apex

Cholesteatoma with Massive Invasion of the Jugular Bulb

Removal of Cholesteatoma from Carotid Wall

Removal of Cholesteatoma from the Internal Auditory Canal with Preservation of the Facial Nerve

Removal of Cholesteatoma with Facial Nerve Grafting (Superior Temporal Rerouting)

Neuromas of the IX, X and XII Cranial Nerves

Surgical Highlights

Vagus Neuroma

Glomus Vagale Tumors

Surgical Highlights

Chondrosarcoma and Other Mesenchymal Tumors

Surgical Highlights

Cholesterol Cysts

Surgical Highlights

Part 4Tips and Pitfalls

Tips and Pitfalls

Part 5Imaging of Illustrative Cases

Imaging of Illustrative Cases

Glomus Temporale Tumors

Class A

Class B

Class Cl

Class C2

Class C3

Class C4

Class De

Class Di

Special Cases of Glomus Temporale Tumors

Bilateral Glomus Temporale Tumors

Glomus Caroticum Associated with Glomus Temporale Tumors

Other Tumors

Carotid Anomalies and Aneurysms

Part 6Color Plates

Color Plates

Anterior Transposition of the Facial Nerve

Ligation of the Sigmoid Sinus

Removal of Class C2 Glomus Temporale Tumor

Facial Nerve Involvement by Glomus Temporale Tumors

Removal of Intradural Extension of Glomus Temporale Tumor (Class Di1)

Chapter 4Infratemporal Fossa Approach Type B

Part 1General Considerations

Rationale, Indications, and Complications

Rationale

Surgical Highlights

Indications

Contraindications

Preoperative Infection

Contralateral Hearing Loss

Complications and Sequelae

Infection

Facial Paralysis

Cosmetic Defect

Mandibular Function

Facial and Tongue Anesthesia

Preoperative Preparation

Premedication

Anesthesia

Antibiotics

Operative Site

Position of the Patient

Draping

Instrumentation

Instruments for Infratemporal Type B Approach

Postoperative Care

Dressings

Drains

Extubation

Analgesia and Antiemetics

Anti-Thromboembolic Prophylaxis

Intravenous

Suture Removal

Part 2Surgical Anatomy

Surgical Anatomy

Bony Landmarks

Vessels and Nerves

Exposure of Clivus

Part 3Surgical Technique

Surgical Technique

Skin Incision

Blind Sac Closure of the External Auditory Canal

Mastoid Periosteal Flap

Transection of the External Auditory Canal

Closure of the External Auditory Canal

Exposure of the Facial Nerve in the Parotid

Exposure of the Facial Nerve in the Parotid

Exposure and Inferior Reflection of the Zygomatic Arch

Inferior Reflection of Temporalis Muscle

Subtotal Petrosectomy

Removal of the External Auditory Canal Skin

Mastoidectomy

Total Removal of the External Auditory Canal Skin and Tympanic Membrane

Skeletonization of the Fallopian Canal

Exenteration of all Pneumatic Cell Tracts

Exposure of the Infratemporal Fossa

Removal of Disease in the Petrous Apex and Clivus

Part 4Applications

Pyramid Apex

Mucosal Cyst

Surgical Highlights

Exposure of the Mucosal Cyst

Removal of the Cyst

Labyrinthectomy

Obliteration of the Cavity and Wound Closure

Epidermoid Cyst

Surgical Highlights

Location of the Epidermoid Cyst

Exposure of the Epidermoid Cyst

Removal of Cholesteatoma Matrix

Meato-Mastoid Rerouting of the Facial Nerve

Obliteration of the Cavity and Wound Closure

Chondrosarcoma

Surgical Highlights

Removal of Chondrosarcoma with Preservation of the Mandibular Nerve (V3)

The Clivus

Chordoma

Surgical Highlights

Exposure of Tumor

Tumor Removal

Sterilization of the Tumor Cavity

Obliteration of the Operative Cavity

Wound Closure

Caudal Extension of Clival Chordomas

Exposure of the Tumor

First Option for Tumor Removal: Anterior Transposition of the Facial Nerve

Surgical Highlights

Removal of the Tumor

IX Nerve Repair and Obliteration of the Cavity

Wound Closure

Second Option for Tumor Removal: Division, Superior Temporal Rerouting, and Reconstruction of the Facial Nerve

Surgical Highlights

Transection of Mastoid Segment of Facial Nerve

Superior Temporal Rerouting of Fallopian Canal

Reconstruction of Facial Nerve

Anterior Clival Chordoma

Part 5Tips and Pitfalls

Tips and Pitfalls

Pyramid Apex

Clivus

Part 6Imaging of Illustrative Cases

Imaging of Illustrative Cases

Pyramid Apex

Clivus

Part 7Color Plates

Color Plates

Congenital Epidermoid Cysts of the Petrous Apex

Chondrosarcoma of the Pyramid Tip

Chordoma of the Pyramid Tip and Clivus

Chapter 5Infratemporal Fossa Approach Type C

Part 1General Considerations

Rationale, Indications, and Complications

Rationale

Surgical Highlights

indications

Juvenile Nasopharyngeal Angiofibroma

Nasopharyngeal Carcinoma

Contraindications

Preoperative Infection

Inoperable Disease

Complications

Morbidity and Mortality

Hearing Loss

Infection

Facial Paralysis

Cosmetic Defect

Mandibular Function

Facial and Tongue Anesthesia

Preoperative Preparation

Premedication

Anesthesia

Antibiotics

Operative Site

Operative Site for the Infratemporal Fossa Approach Type C

Position of the Patient

Draping

Instrumentation

Postoperative Care

Dressings

Drains

Extubation

Analgesia and Antiemetics

Anti-Thromboembolic Prophylaxis

Intravenous

Suture Removal

Part 2Surgical Anatomy

Surgical Anatomy

Anatomical Areas and Spaces of the Skull Base

Skull Base from Perspective of the Infratemporal Fossa Type C Approach

Principle of the Infratemporal Type C Approach

Part 3Surgical Technique

Surgical Technique

Skin Incision

Mastoid Periosteal Flap

Transection of the External Auditory Canal

Closure of the External Auditory Canal

Exposure of the Facial Nerve in the Parotid

Inferior Reflection of the Zygomatic Arch and Temporalis Muscle

Inferior Reflection of the Zygomatic Arch

Elevation of the Temporalis Muscle

Subtotal Petrosectomy

Removal of the External Auditory Canal Skin

Mastoidectomy

Total Removal of the External Auditory Canal Skin and Tympanic Membrane

Exenteration of All Pneumatic Cell Tracts

Exposure of the Infratemporal Fossa

Identification of the Vertical Segment of the Internal Carotid Artery

Inferior Displacement of the Mandibular Condyle

Exposure of Pterygoid Process

Removal of Disease

Part 4Applications

Infratemporal Fossa and Peritubal Space

Melanoma

Surgical Highlights

Exposure of Tumor

Tumor Removal

Obliteration of the Surgical Cavity and Wound Closure

Oral Cavity

Combined Type C - Transoral Resection of Adenoid Cystic Carcinoma

Surgical Highlights

Transoral Removal of Tumor

Wound Closure

Pterygopalatine Fossa and Sphenoid Sinus

Adenoid Cystic Carcinoma of Pterygopalatine Fossa, Infratemporal Fossa and Sphenoid Sinus

Surgical Highlights

Exposure of the Tumor

Removal of the Tumor

Obliteration of the Cavity and Wound Closure

Parasellar Region

Juvenile Nasopharyngeal Angiofibroma

Surgical Highlights

Exposure of the Tumor

Removal of the Tumor

Obliteration of the Cavity

Cavernous Sinus

Local Irradiation of Cavernous Sinus

Exposure of Tumor within Cavernous Sinus

Nasopharynx

Nasopharyngeal Carcinoma

Surgical Highlights

Exposure of the Tumor

Tumor Removal

Obliteration of the Cavity and Wound Closure

Parapharyngeal Space

Part 5Tips and Pitfalls

Tips and Pitfalls

Part 6Imaging of Illustrative Cases

Imaging of Illustrative Cases

Infratemporal Fossa and Peritubal Space

Oral Cavity

Pterygopalatine Fossa and Sphenoid Sinus

Parasellar Region

Cavernous Sinus

Nasopharyngeal Carcinoma

Part 7Color Plates

Color Plates

Infratemporal Fossa Approach Type C for a Juvenile Nasopharyngeal Angiofibroma Class III

Tent Nasopharyngeal Carcinoma after Irradiation

Infratemporal Fossa Approach Type C for a Neurofibroma of the Sphenopalatine Ganglion

Chapter 6Transtemporal Supralabyrinthine Approach

Part 1General Considerations

Rationale, Indications, and Complications

Rationale

Surgical Highlights

Indications

Contraindications

Preoperative Infection

Cerebellopontine Angle Tumors

Complications

Sensorineural Hearing Loss

Conductive Hearing Loss

Facial Paralysis

CSF Leak

Extradural Hematoma

Preoperative Preparation

Premedication

Anesthesia

Antibiotics

Operative Site

Position of the Patient

Draping

Instrumentation

Instruments for Transtemporal Supralabyrinthine Approach

Postoperative Care

Dressings

Drains

Sutures

Part 2Surgical Anatomy

Surgical Anatomy

Topographic Anatomy of the Middle Cranial Fossa

The Proximal Segments of the Facial Nerve

Arterial System of the Internal Auditory Canal

Part 3Surgical Technique

Surgical Technique

Skin Incision

Exposure of Temporalis Fascia

Exposure of the Temporal Squama

Craniotomy

Elevation of the Middle Cranial Fossa Dura

Exposure of the Meatal Plane

Introduction of Articulated Middle Fossa Retractor

Identification of Blue Line of Superior Semicircular Canal

Identification and Exposure of the Internal Auditory Canal

Vestibular Neurectomy

Wound Closure

Part 4Applications

Vestibular Neurectomy

Surgical Highlights

Indications and Results

Ménière’s Disease

Bilateral Ménière’s Disease

Peripheral Labyrinthine Disease

Other Indications

Contraindications

Only Hearing Ears

Central Vestibular Dysfunction

Age

Complications

Hearing Loss

Facial Paralysis

CSF Leak

Vestibular Compensation

Results

Alternative Approaches

Facial Nerve Decompression for Idiopathic Paralysis and Herpes Zoster

Surgical Highlights

Preliminary Steps

Exposure of the Facial Nerve

Localization of the Lesion with Intraoperative Evoked Electromyography

Decompression of the Facial Nerve in Idiopathic Paralysis

Decompression of the Facial Nerve in Herpes Zoster Oticus

Wound closure

Management of Idiopathic and Herpetic Facial Palsy

Indications and Results

Contraindications

Motivation

Contralateral Deafness

Complications

Conductive Hearing Loss

Sensorineural Hearing Loss

Longitudinal Fractures of the Temporal Bone

Acute Injury of the Facial Nerve

Surgical Highlights

Preliminary Steps of Surgical Exposure

Intratemporal Fracture Sites

Exposure of the Facial Nerve in the Internal Auditory Canal

Facial Nerve Injuries

Meato-Tympanic Rerouting and Nerve Graft

Long Standing Injury of the Facial Nerve

Surgical Highlights

Exposure of the Facial Nerve

Management of Acute and Long Standing (Chronic) Injuries of the Facial Nerve

Indications

Contraindications

Results

Supralabyrinthine Tumors and Cholesteatomas

Combined Transtemporal-Transmastoid Approach

Surgical Highlights

Skin Incision and Mastoido-Temporal Exposure

Transmastoid Approach

Transtemporal Approach

Exposure of the Tumor

Resection of the Tumor

Facial Nerve Grafting

Reconstruction of the Ossicular Chain

Wound Closure

Combined Transtemporal-Parotid Approach

Surgical Highlights

Skin Incision and Mastoidectomy

Tumor Resection

Parotid Extension

Meato-Parotid Rerouting of Facial Nerve and Grafting

Combined Transtemporal-Transmastoid Approach converted to Subtotal Petrosectomy

Surgical Highlights

Skin Incision and Mastoidectomy

Transmastoid Approach

Transtemporal Exposure

Anterior Meato-Tympano-Mastoid Rerouting and Grafting of the Facial Nerve

Wound Closure

Surgical Removal of Supralabyrinthine Tumors and Cholesteatoma

Indications

Contraindications

Preoperative Deafness

Extensive Erosion of the Basal Turn of the Cochlea without Sensorineural Hearing Loss

Contralateral Hearing Loss

Complications

Deafness

Conductive Hearing Loss

Facial Paralysis

Conversion to Subtotal Petrosectomy

Results

Intrameatal Tumors

Acoustic Neuroma

Surgical Highlights

Small Intrameatal Acoustic Neuroma

Large Intrameatal Acoustic Neuroma

Cavernous Hemangioma of Scarpa’s Ganglion

Surgical Highlights

Selective Cochlear Neurectomy

Surgical Highlights

Petrosal Neurectomy

Surgical Highlights

Surgical Technique

Repair of Middle Fossa CSF Leaks

Surgical Highlights

Skin Incision and Mastoidectomy Exposure and Management of the Meningocele

Repair of the Defect

Decompression of the Narrow Internal Auditory Canal

Meato-Synangiosis

Surgical Highlights

Skin Incision and Preparation of the Arterial Flap

Exposure of the Internal Auditory Canal

Muscle Graft and Arterial Flap

Wound Closure

Part 5Tips and Pitfalls

Tips and Pitfalls

Part 6Imaging of Illustrative Cases

Imaging of Illustrative Cases

Vestibular Neurectomy

Facial Nerve Decompression for Idiopathic Paralysis and Herpes Zoster

Longitudinal Fractures of the Temporal Bone

Supralabyrinthine Tumors and Cholesteatoma

Repair of Middle Fossa CSF Leaks

Intrameatal Tumors

Decompression of Narrow Internal Auditory Canal

Part 7Color Plates

Color Plates

Vestibular Neurectomy

Longitudinal Fracture of Temporal Bone

Facial Nerve Decompression for Idiopathic Paralysis

Supralabyrinthine Facial Nerve Neuroma

Transtemporal-Transmastoid Facial Nerve Grafting with Meato-tympanic Rerouting

Chapter 7Translabyrinthine Approach

Part 1General Considerations

Rationale, Indications, and Complications

Rationale

Surgical Highlights

Indications

Contraindications

Hearing

Transverse Temporal Bone Fracture

Poor Pneumatization of Temporal Bone

Chronic Otitis Media

Complications

CSF leak

Preoperative Preparation

Premedication

Anesthesia

Antibiotics

Cochleo-Vestibular Neurectomy

Acoustic Tumors

Operative Site

Position of the Patient

Draping

Draping for Translabyrinthine Approach

Instrumentation

Instruments for Translabyrinthine Approach

Postoperative Care

Dressing

Drains

Suture Removal

Part 2Surgical Technique

Surgical Technique

Skin Incision

Mastoidectomy

Labyrinthectomy

Identification of the Internal Auditory Canal

Identification of the Facial Nerve

Opening of the Internal Auditory Canal

Part 3Applications

Applications of the Translabyrinthine Approach

Cochleo-Vestibular Neurectomy

Surgical Technique

Wound Closure

Part 4Tips and Pitfalls

Tips and Pitfalls

Part 5Imaging of Illustrative Cases

Imaging of Illustrative Cases

Cochleo-vestibular Neurectomy

Intrameatal Tumor

Part 6Color Plates

Color Plates

Cochleo-vestibular Neurectomy

Chapter 8Petrosectomy and Radical Dissection of Retromandibular Fossa

Part 1General Considerations

Rationale, Indications, and Complications

Rationale

Surgical Highlights

Indications

Contraindications

Facial Nerve Graft

Complications

Wound Healing

Malocclusion

Preoperative Preparation

Premedication

Anesthesia

Antibiotics

Operative Site

Position of the Patient

Draping

Instrumentation

Instruments for Petrosectomy with Retromandibular Dissection

Postoperative Care

Dressings

Drains

Suture Removal

Part 2Surgical Anatomy

Surgical Anatomy

Topographic Anatomy of the Retromandibular Fossa

Types of Petrosectomy in Radical Dissection of the Retromandibular Fossa

Partial Mastoido-Tympanectomy

Total Mastoido-Tympanectomy

Extended Petrosectomy

Part 3Surgical Highlights

Surgical Highlights

Partial Mastoido-Tympanectomy

Skin Incision

Dissection of the Retromandibular Fossa

Removal of Mastoid and Tympanic Bone

Facial Nerve Grafting

Wound Closure

Total Mastoido-Tympanectomy

Surgical Highlights

Skin Incision

Temporo-Cervical Exposure

Removal of Mastoid and Tympanic Bone

The Surgical Site After Tumor Removal

Facial Nerve Grafting

Wound Closure

Extended Petrosectomy

Surgical Highlights

Skin Incision

Soft Tissue Dissection

Mastoidectomy and Mastoido-Tympanectomy

Petrosectomy

Exposure of the Infratemporal Fossa

Tumor Removal

Facial Nerve Grafting

Wound Closure

Part 4Tips and Pitfalls

Tips and Pitfalls

Part 5Imaging of Illustrative Cases

Imaging of Illustrative Cases

Partial Mastoido-Tympanectomy

Total Mastoido-Tympanectomy

Extended Petrosectomy

Part 6Color Plates

Color Plates

Total Mastoido-Tympanectomy

Extended Petrosectomy

Chapter 9Anesthesia for Surgery of the Skull Base

U.Aeppli

Anatomo-Physiological Considerations

Premedication

Induction

Monitoring

Maintenance of Anesthesia

Blood Replacement

Hypotensive Anesthesia

Extubation and Postoperative Care

Chapter 10Interventional Neuroradiology of Skull Base TumorsA. Valavanis

Rationale, Indications, and Complications

Rationale

Indications

Contraindications

Preembolization Evaluation

Angiographic Evaluation

Technique of Embolization

General Principles

Vascular Composition

Embolization with Microparticles

Embolization with Fluid Materials

Dangers and Complications

Dangerous Anastomoses

Techniques of Embolization in the Presence of Dangerous Anastomoses

Balloon-Occlusion of the Internal Carotid Artery

Rationale

Indications

Technique of Balloon-Occlusion of the Internal Carotid Artery

Functional Angiographic Evaluation

Tolerance Test

Placement and Detachment of the Balloons

Postprocedural Care

Complications

Embolization of Angiofibromas

Indications

Angiographic Evaluation

Embolization

Embolization of Glomus Temporale Tumors

Indications

Angiographic Evaluation

Embolization

Literature

Index

Chapter 1

Subtotal Petrosectomy

“The danger of an operation outside the dura mater is small; indeed, under modern conditions of operation practically nil. No hesitation need therefore be felt in exposing the dura mater to any extent that may be necessary for complete removal of the disease.”

Charles A. Ballance

Part 1

General Considerations

Rationale, Indications, and Complications

Rationale

Subtotal petrosectomy is a complete exenteration of all pneumatic cell tracts of the temporal bone. This includes the retrosigmoid, retrofacial, antral, retrolabyrinthine, supralabyrinthine, infralabyrinthine, peritubal and pericarotid cell tracts. The isthmus of the eustachian tube is also obliterated.

The name subtotal petrosectomy indicates that at the end of the procedure only the otic capsule, a thin shell of cortical bone covering the dura, and a few remnants of the suprametal and apical cells medial to the otic capsule are preserved. If needed, the otic capsule, the internal auditory canal, and all cell tracts can be included in the resection, preserving only the bone around the porus acousticus.

The external auditory canal may be left open with a wide meatoplasty, or the cavity may be obliterated with soft tissue and the external canal closed as a blind sac.

Surgical Highlights

• Retroauriculo-temporal skin incision

• Blind sac closure of the external auditory canal

• Skin of the external auditory canal, malleus, incus and stapes arch removed

• Complete pneumatic tympanomastoid space exposed and exenterated

• Eustachian tube obliterated

• Obliteration of the cavity with abdominal fat and a temporalis muscle flap or large meatoplasty with open cavity

Indications

Subtotal petrosectomy is performed as an isolated procedure for post-traumatic or postoperative CSF leaks, supralabyrinthine and infralabyrinthine cholesteatomas, and tumors. On occasion, it may also be used for permanent obliteration of mastoid cavity for chronic middle ear disease when there is no possibility of hearing reconstruction (Table 1-1).

The cavity may be left open if permanent drainage is necessary because of infection or residual disease. The external auditory canal is closed and the cavity obliterated after radical removal of the lesion or to provide a seal against infection or CSF leak.

The selection of the specific approach to lesions of the temporal bone is described on page 50.

Subtotal petrosectomy is also the first stage in most procedures illustrated in this book, particularly the transotic approach to the posterior fossa and for those requiring exposure of the internal carotid artery, e.g., infratemporal approaches A, B, and C (Table 1-2).

Table 1-1 Indications for Subtotal Petrosectomy

Tumors

34

Benign

25

Malignant

  9

CSF Leak

31

Spontaneous

  4

Postoperative

23

Post-traumatic

  4

Cholesteatoma

28

Supralabyrinthine

20

Infralabyrinthine

  8

Transverse temporal bone fracture

27

Chronic otitis media

15

Total

135

Table 1-2 Subtotal Petrosectomy Combined with Another Procedure

Transotic approach

111

Infratemporal Type A

216

Infratemporal Type B

  39

Infratemporal Type C

  57

Retromandibular fossa

  44

Total

467

Contraindications

Preoperative Contaminated Wounds

Obliteration of the cavity with fat is contraindicated in contaminated wounds. For instance, after removal of an infected cholesteatoma, the wound is left open to granulate. In the presence of infection with exposed dura and CSF leak (e.g., osteonecrosis of the temporal bone), the cavity is obliterated with vascularized temporalis or sternocleidomastoid muscle, and not with fat grafts.

Complications

Infection

Wound infection with necrosis of the abdominal fat graft and/or muscle flaps occurred in 1.4% of cases.

Wound Healing

Insufficient eustachian tube closure and recanalization of the external auditory canal were observed in less than 0.5% of cases.

Preoperative Preparation

Premedication

The patient is premedicated with pethidine (morphine derivative) 50 mg IM (intramuscular); and atropine 0.5 mg IM, 30 minutes before surgery.

Anesthesia

Anesthesia (see Chapter 9) is induced with sodium thiopental (Pentothal; Abbot) and a short acting muscle relaxant, Lysthenon (Chemie Linz), 1 mg/kg. It is important that a short acting muscle relaxant be used so that nerve function will not be impaired during the surgery. An oral endotracheal tube is secured with a silk suture to the teeth. The patient is maintained on nitrous oxide and an inhalation agent (Fluothane, Ethrane).

Hypotensive anesthesia (sodium nitroprusside, 5-10 mg/hr) is used in most cases to decrease blood loss. Systolic blood pressure is maintained between 80 and 100 mm Hg. The reactive tachycardia is controlled with clonidin hydrochloride (Catapresan; Boehringer).

All patients having surgery of this magnitude need careful intra-and postoperative monitoring with central venous and arterial lines. Urinary output is measured with a urethral catheter.

Corticosteroids are not routinely used.

Antibiotics

When the subarachnoid space is not opened, sulfamethoxazole and trimethoprim (Bactrim; Roche), 2 ampules every 12 hours IV (intravenous), is started in the operating room. It is continued until the intravenous is removed (first or second day) and Bactrimforte is continued PO (per os) for five days. If the subarachnoid space is opened, chloromycin, 1 mg every 8 hours IV, is given for 5 days. If the surgical field is infected with pseudomonas, aminoglycosides and penicillin derivatives are given IV for four to six weeks postoperatively.

Operative Site

Figure 1-1 Preoperative preparation for subtotal petrosectomy

The hair of the temporal area is clipped for 7 cm above and behind the ear the night before surgery. The area is shaved and prepared with Betadine (soap and solution; Mundipharma) after the induction of general anesthesia in the operating room.

The abdominal left lower quadrant and suprapubic areas are shaved and prepared for the fat graft.

The contralateral lower leg is shaved and prepared from the knee to the foot if a sural nerve graft is anticipated.

Position of the Patient

Figure 1-2 Arrangement of patient and operating team

The patient lies supine with the head turned away from the surgeon. The angle between the head and shoulder should be more than 90 degrees to allow adequate working space. The position of the table, patient, equipment and personnel are shown.

1

Surgeon

2

Anesthetist

3

Scrub nurse

A

Anesthetic apparatus

B

Instrument table

C

Diathermy apparatus including bipolar microcoagulation

D

Suction

E

Irrigation

F

Intravenous fluids

O

Operating microscope

H

Arterial line.

Draping

Figure 1-3 Draping for subtotal petrosectomy

A A cloth cap has been placed over the model’s hair to simulate the shaving described in Figure 1-1. Paper drapes with adhesive edges are placed around the surgical field.

B A second layer of cloth drapes is held with towel clips. The posterior face is left exposed in case the intraparotid portion of the facial nerve must be exposed.

C A sterile plastic trash bag is taped with sterile waterproof tape to catch excess irrigation and keep surgeon and patient dry. The other end of the bag is placed in a bucket in case the bag should leak.

Instrumentation

Instruments for Subtotal Petrosectomy

Figure 1-4

A General instruments

* Developed or modified in Zurich. All instruments are available through: F. L. Fischer, D-7800 Freiburg West Germany and Karl Storz, D-7200 Tuttlingen West Germany

B Detail of straight microraspatories

The right and left microraspatories are universal instruments for otologic surgery. The surface is slightly concave on one side and the tip has a fine edge. A microraspatory may be used as a scraper, as a cutting instrument, and as a small curette.

C Detail of microinstruments

The neurectomy knife (1) is used only for soft nerve tissue. The tenotome (2) is a stronger instrument used for fibrous tissue and epineurium.

For cleaning, microinstruments are immersed in an ultrasonic bath with HaemoSol* (1 measure of powder to 2 liters of water). After cleaning, the microinstruments are rinsed, dried, and placed in a metal stand for gas sterilization.

* Merz & Dade AG, Duedingen, Switzerland

D Drill handpieces and burrs*

The conical burr (1) is used for heavy bone removal with the short handpiece (2). The diamond burrs (3) and cutting burrs (4) are 7.0 to 0.6 mm in diameter. The straight and angled handpieces (5) are used for finer work within the temporal bone.

The handpieces are cleaned with warm water and a brush (avoid placing them in water). After cleaning, the handpieces are lubricated for one second with KaVo Intra Spray 2130* and sterilized in hot air up to 180°C or in the autoclave up to 125°C. After sterilization, the handpieces are kept upright to permit outflow of excess lubricant. Before use, they are resterilized in the autoclave (short program).

* KaVo, Kaltenbach & Voigt, Bismarckring 39 D-7950 Biberach a.d. Riss, West Germany

E Detail of the cutting and diamond burrs

The diamond burrs come in the following sizes: 7.0, 6.0, 5.0, 4.0, 3.1, 2.3, 1.8, 1.4, 1.0, 0.8, and 0.6 mm. Note the number of cutting edges on the cutting burrs; burrs with fewer teeth are dangerous because they tend to catch on bone edges. Burrs with more teeth are too slow. The sizes and the number of cutting edges on the burrs are: 7.0 - 16, 6.0 - 16, 5.0 - 12, 4.5 - 12, 4.0 - 12, 4.0 - 12, 3.5 - 12, 2.7 - 12, 2.3 - 10, 1.8 - 8, 1.4 - 8, and 1.0 - 6. The 7 mm conical burr has 12 cutting edges.

Figure 1-5 Instruments for abdominal fat graft

1

Large and small curved clamps (Péan)

2

Long smooth forceps

3

Large and small curved scissors

4

Long and short toothed forceps

5

Scalpel with # 10 blade

6

Trocar for suction drain, 3.0 mm

7

Small needle holder

8

Skin hook

9

Large skin rake

Figure 1-6 Instruments for harvesting sural nerve graft

  1

Small needle holder

  2

Langenbeck retractor

  3

Small skin rake

  4

Skin hook

  5

Small curved clamps (Péan)

  6

Large curved clamp

  7

Short smooth forceps

  8

Tympanoplasty scissors and small curved scissors

  9

Small toothed forceps

10

Surgical scalpel with # 10 blade

11

Syringe for local anesthetic

Figure 1-7

A Instruments for facial nerve anastomosis

* Developed or modified in Zurich. All instruments are available through: F. L. Fischer, D-7800 Freiburg West Germany and Karl Storz, D-7200 Tuttlingen West Germany

B Detail of instruments for nerve anastomosis

The tips of the neurectomy scissors (1) and nerve scissors (2) are shown enlarged. The neurectomy scissors are used only for soft nerve tissue. The nerve scissors are used for epineurium and to cut the anastomotic surface in larger nerves. Note the nerve scissors (2) have a serrated edge.

Figure 1-8 Fibrin glue kit*

A Fibrin glue is available as a kit containing freeze-dried fibrinogen (1), aprotinin (2), freeze-dried thrombin 500 (3), freeze-dried thrombine 4 (5), and calcium chloride (4). The substrates are mixed to form two components: sealer and thrombin solution. To prepare the sealer, fibrinogen concentrate is dissolved in the accompanying stock solution of fibrinolyis inhibitor (aprotinin) at 37 °C. Thrombin is dissolved in 40 mM calcium chloride solution to a concentration of either 500 or 4 (NIH) units of thrombin per milliliter.

The two components (fibrinogen and thrombin) are applied separately with tuberculin syringes (6). The sealant consolidates at the site of application. The time for hardening is determined by the thrombin concentration. For fast set glue, Thrombin 500 is used, and for slow set glue, Thrombin 4 is used. For fixation of nerve anastomoses, a more diluted fibrinogen-aprotinin solution (1:10, i.e. 0, 1 ml fibrinogen-aprotinin and 0,9 ml Ringer’s solution) is used to avoid forming a strong fibrosis between the anastomotic surfaces. The mixed fibrinogen and thrombin solutions are placed on a vibrating platform (Fibrotherm) where they are shaken for 10 minutes at 37 °C.

* Immuno AG, A-1000 Vienna Austria

B Fibrotherm heating mixer for fibrin glue

The reconstitution of the fibrinogen solution requires 10 to 15 minutes on the heating and stirring device. The fibrinogen component is seen in one of the heating wells of the device (arrow).

Figure 1-9 Bien Air Drill*

The foot peddle with reverse and continuous gradient from 0 to 40,000 RPM is shown with the motor and attached angled handpiece. The motor and cable are wiped clean with alcohol and sterilized in gas at 60°C.

* Bien Air Chm. de Grillons 13-15 CH-2500 Bienne Switzerland

Figure 1-10 Tri-Tom 600 monopolar and micro-bipolar coagulator*

This unit permits simultaneous unipolar and bipolar coagulation. The bipolar coagulation has 14 steps. For work close to nerves a setting of 4 to 8 is used. Higher settings are necessary for extensive coagulation away from neurovascular structures.

* Meditron AG, Kreuzstr. 32 CH-6010 Kriens-Luzern Switzerlan

Figure 1-11 Shaw scalpel*

The Shaw scalpel is used only for cutting the scalp. It is very helpful in reducing bleeding from wound edges.

A Diathermy unit with temperature control. A temperature of 160° is used to incise the skin and 210° for the subcutaneous layer.

* Oximetrix Inc., Mt. View LA 94043, USA

B Knife handle and blade

Figure 1-12 Lempert Storz binocular loupes*

The ocular loupes provide a 2.5 x magnification. The optical correction and angle of view can be adapted to individual needs.

* Karl Storz, D-7200 Tuttlingen West Germany

Figure 1-13 Operating microscope

The Contraves “weightless” counterbalanced stand* is fitted with Wild optics**, an Ikegami Tricolor camera ITC-350M, and a Minolta X-300 camera with autofocus, winder and infrared remote control. The film used is Kodak Ektachrome 160 ASA. A 250 f lens is used for the following approaches: subtotal petrosectomy, transotic, infratemporal fossa type A, B and C. A 200 f lens is used for the transtemporal supralabyrinthine and translabyrinthine approaches.

* Contraves AG Schaffhauser Str. 580 CH-8052 Zurich, Switzerland

** Wild Leitz AGCH-9435 Heerbrugg, Switzerland

Figure 1-14 Contraves table*

The new Contraves table, which has the center of rotation in the temporal bone, allows ideal positioning and rotation of the patient without shifting the microscope or surgeon’s position.

* Contraves AGSchaffhauser Str. 580CH-8052 Zurich, Switzerland

Figure 1-15 Operating room equipment

In addition to the microscope and Contraves table, the surgeon has a motor driven chair (Contraves) and the scrub nurse has a special double sided Mayo stand (Contraves).

Postoperative Care

Dressings

Figure 1-16 Dressings

The compression dressing is applied immediately after surgery. If the subarachnoid space has been opened, the dressing is left in place for five days. Otherwise it is removed one to two days after surgery. A cloth cap has been placed on the model to simulate shaving of the head.

A The pinna is protected from folding or excessive pressure with a self adhesive foam rubber pad.*

* Richards Medical Comp.1450 Brooks Rd.Memphis Tn 38116, USA

B The foam pad is folded over the pinna.

C A gauze pad can also be cut and folded over the pinna to protect it.

D The gauze pad had been folded over the pinna.

E Extra gauze padding is placed over the ear.

F The bandage is reinforced with a kling wrap.

G The entire head is wrapped with adhesive foam tape

Drains

A 3.0 mm suction drain is placed under the scalp over the temporal squama. The tip of the drain is placed adjacent to the cut surface of the temporalis muscle, not over the mastoid cavity. The drain is left until the drainage is less than 10 cc/24 hours. If the subarachnoid space has been entered during surgery, the drain is removed as soon as the compression bandage is applied to avoid aspirating CSF into the wound.

Extubation

The patient is extubated immediately after surgery.

Analgesia and Antiemetics

Chlorpromazine (Largactil; Rhône-Poulenc), 25 mg suppository three times per day TID.

Noramidopyrin (Novalgin; Hoechst), 2-5 ml IV every 8 hours as needed.

Diclofenac sodium (Voltaren; Geigy), 75-150 mg suppository initially, followed by 75 mg PO per day.

Anti-Thromboembolic Prophylaxis

Low dose heparin, 5000 units subcutaneous twice a day, is continued until the patient is ambulating. In poor risk patients, decoumarin is continued orally.

Intravenous

The intravenous is left until the patient is taking fluids PO, usually 24 to 48 hours.

Suture Removal

If the subarachnoid space has not been opened, the sutures are removed after 8 days. If the subarachnoid space has been opened, the sutures are left for 12 days.

Abdominal Wound

The abdominal wound is drained with a suction drain that is removed when the drainage is less than 10 cc/24 hours. The sutures are removed after 10 days.

Leg Wound

The leg wound is closed without a drain. Sutures are left at least 14 days until the wound is healed.

Part 2

Surgical Technique

Surgical Technique

Skin Incision

Figure 1-17 The skin incision

A postauricular “S” shaped incision is made from the temporal region to 2 cm below the mastoid tip (A-B). The incision is placed along the postauricular hair line to keep the wound closure posterior to the operative cavity. The superior portion of the incision (A-C) is made at the end of the procedure if a temporalis muscle flap is needed. A diathermy knife (Shaw scalpel) is helpful because it reduces the bleeding from the skin margins.

Blind Sac Closure of External Auditory Canal

Figure 1-18 Mastoid periosteal flap

The postauricular skin is reflected anteriorly in a plane superficial to the temporalis muscle, postauricular muscle and periosteum. An anteriorly based flap is created from the mastoid periosteum and soft tissues. This flap is left attached to the cartilaginous canal and will be used as a second layer in the closure of the external auditory canal.

Figure 1-19 Transection of external auditory canal

A The plane of elevation beneath the periosteal flap is continued to the bony-cartilaginous junction of the external auditory canal, which is transected at this level.

B Transection of the anterior portion of the external auditory canal is facilitated by passing a curved clamp through the soft tissue anterior to the canal cartilage and then cutting down to the clamp with a knife. This maneuver avoids injury of the facial nerve and the vascular parotid tissue anterior to the cartilaginous canal.

Figure 1-20 Closure of the external auditory canal (ocular loupes)

A Ocular loupes (Fig. 1-12) are used for magnification. The skin of the cartilaginous canal is elevated for 1 cm from the cut margin toward the external meatus with tympanoplasty scissors to facilitate eversion of the canal skin.

B Two 2-0 chromic catgut stay sutures are placed through the external canal skin. The free ends extend inside the cuff of skin.

C The two sutures are brought through the meatus with a curved clamp passed through the external auditory meatus.

D Tension on the stay sutures everts the canal skin through the external meatus. The tragus is retracted with a skin hook.

E The skin edges are closed with 4-0 vicryl sutures. Colorless sutures are used because they are left until they dissolve.

F Completed closure of the external auditory canal.

G The periosteal flap is folded over the closed meatus.

H The periosteal flap is sutured to the cartilage of the external auditory canal with 2-0 chromic catgut.

Exenteration of Pneumatic Middle Ear Cleft

Figure 1-21 Removal of the lateral external auditory canal skin (ocular loupes)

A The skin of the bony external auditory canal is elevated with a Key raspatory. As much skin as possible is excised so that it will not interfere with removal of the posterior bony canal wall.

B The skin cuff is removed from the lateral bony canal with tympanoplasty scissors.

Figure 1-22 Mastoidectomy

A The soft tissues are elevated from the mastoid with the mastoid raspatory. The attachment of the sternocleidomastoid muscle is freed from the lateral portion of the mastoid tip. The temporalis muscle is held superiorly with a #2 silk suture from its free edge to the fascia. The resulting exposure extends from the mastoid tip to above the temporal line and from the zygomatic arch to 1 cm posterior to the mastoid emissary vein.

B The soft tissues are held with two articulated self-retaining retractors. The sternocleidomastoid muscle is retracted to expose the entire mastoid tip.

C The initial stages of the mastoidectomy are done without magnification. Drilling is extended well above the level of the middle fossa dura and behind the sigmoid sinus to facilitate saucerization of the cavity. All pneumatic cells are removed. A thin sheet of bone is left protecting the dura and sigmoid sinus. The middle cranial fossa dura is identified first, followed by the sigmoid sinus, sinodural angle, mastoid tip cells, and the mastoid antrum. The posterior bony canal wall is lowered to the level of the remaining skin margin. Drilling is done with a conical burr with continuous suction-irrigation. All overhanging edges of bone are removed to allow collapse of the overlying tissues when the wound is closed. This will reduce the size of the cavity.

Figure 1-23 Removal of remaining external auditory canal skin (microscope)

A A microraspatory is used to elevate the remnants of the external auditory canal skin down to the tympanic annulus. The dissection is facilitated and the bleeding reduced by protecting the skin with a small gauze strip soaked in 1: - 1000 adrenalin (see inset).

B The tympanic annulus is elevated to expose the short process of the malleus, chorda tympani, and incudostapedial joint.

C The chorda tympani is sectioned with large Bellucci scissors.

D The incudostapedial joint is separated with a 45° angled 1.5 mm hook or joint knife.

E The malleus is cut at its neck with a malleus nipper.

F The tensor tympani tendon is sectioned with large Bellucci scissors.

G The tympanic membrane is now removed in continuity with the cuff of canal skin. The external canal is once again inspected to ensure no remnant of squamous epithelium is left behind because the cavity is destined to be obliterated.

Figure 1-24 Pneumatic cell tracts in subtotal petrosectomy (microscope)

A All air cell tracts associated with the middle ear and mastoid should be thoroughly removed. The facial nerve is identified at the digastric ridge by following the stylomastoid periosteum which runs medial and anterior to the stylomastoid foramen. The superior canal wall is removed with suction-irrigation and 5 to 7 mm sharp and diamond burrs. The incus and malleus head are removed. The tympanic segment of the facial nerve is identified inferior to the lateral semicircular canal at the oval window. The posterior canal wall is removed exposing the fallopian canal from the oval window to the stylomastoid foramen. All bone except for a thin covering is removed from the nerve. The pneumatic cells are exenterated in the following order: retrosigmoid, retrofacial, retrolabyrinthine, supralabyrinthine, infralabyrinthine, pericarotid and supratubal.

The supralabyrinthine cells are situated in a space limited by the middle cranial fossa dura, the tympanic, geniculate and labyrinthine segments of the facial nerve, and the lateral and superior ampullae. Complete removal of the supralabyrinthine cells requires a mastery of the anatomy of the facial nerve. From this approach the labyrinthine nerve segment forms an acute angle of less than 20° with the tympanic segment.

In order to remove the infralabyrinthine cells completely, one must be prepared to drill away a large part of the inferior tympanic bone and skeletonize the carotid foramen as well as the jugular bulb.

B Surgical site after exenteration of all pneumatic cell tracts. ET - eustachian tube; ICA - internal carotid artery; JB - jugular bulb; SS - sigmoid sinus; LSC - lateral semicircular canal; PSC - posterior semicircular canal; SSC - superior semicircular canal; MCF DURA - middle cranial fossa dura.

Figure 1-25 Removal of the stapes arch (microscope)

A Crurotomy scissors are used to cut the anterior crus.

B The posterior crus is cut with crurotomy scissors and the stapedial tendon with large Bellucci scissors. The footplate and annular ligament of the stapes remain intact.

The stapes arch is removed to avoid inadvertent luxation of the footplate when the surgeon is working deeper in the temporal bone. This step also facilitates elevation of the facial nerve from the fallopian canal without injuring the lateral semicircular canal (see Fig. 3-35). In addition, removal of the arch prevents luxation of the stapes when the cavity is packed with abdominal fat. After the arch is removed the mucosa is cleaned from the footplate.

Obliteration of the Eustachian Tube

Figure 1 -26 Obliteration of the eustachian tube (microscope)

A The internal carotid artery (ICA) is followed superiorly to the medial wall of the eustachian tube. The carotid canal may be dehiscent at this point. The bony eustachian tube is removed as far as the isthmus with 2 to 3 mm diamond burrs.

B The bony cartilaginous junction is coagulated with bipolar forceps (Fig. 1-4A, No 21) to destroy the mucosa.

C The eustachian tube is obliterated with bone wax, which is firmly packed with a suction tip covered with a neurosurgical cottonoid (inset).

D The eustachian tube orifice is sealed with a musculofascial graft from the temporalis muscle held in place with fibrin glue. In a more extensive procedure (e.g., infratemporal approach Type A) this step is performed as a part of the wound closure to avoid displacement of the graft.

Obliteration of the Operative Cavity

Figure 1-27 Removal of the mastoid tip (microscope)

Removal of the mastoid tip is important for adequate soft tissue obliteration of the inferior portions of the cavity. The mastoid tip is left in place until the end of the procedure because it serves to hold the soft tissues out of the surgical field.

A The bone is thinned until the periosteum lateral to the stylomastoid foramen is exposed.

B The last shell of bone is cracked and rotated away from the stylomastoid foramen with a rongeur.

C The attachments of the digastric and sternocleidomastoid muscles are cut with large curved scissors.

Figure 1-28 Obliteration of the middle ear cleft with abdominal fat

Abdominal fat is obtained from a left lower quadrant incision. The cavity is firmly packed with appropriately sized and fitted pieces of fat held in place with fibrin glue.

Figure 1-29 Transposition of the temporalis muscle

A The skin incision is extended superiorly for exposure of the temporalis muscle (A-C in Fig. 1-17). The posterior two thirds of the muscle are mobilized, and are separated from the remainder of the muscle by a vertical incision parallel to the fibers. Bleeding is reduced with the diathermy knife (Shaw scalpel).

B