Table Of ContentINTRAOPERATIVE CLINICAL
NEUROPHYSIOLOGY
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INTRAOPERATIVE
CLINICAL
NEUROPHYSIOLOGY
A Comprehensive Guide to
Monitoring and Mapping
Edited by
Mirela V. Simon, MD
Director, Intraoperative Monitoring Unit
Massachusetts General Hospital
Department of Neurology
Harvard Medical School
Boston, Massachusetts
NEW YORK
Acquisitions Editor: Beth Barry
Cover Design: Steve Pisano
Compositor: Publication Services, Inc.
Printer: Sheridan Press
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Library of Congress Cataloging-in-Publication Data
Intraoperative clinical neurophysiology / edited by Mirela V. Simon.
p. ; cm.
Includes bibliographical references and index.
ISBN 978-1-933864-46-4
1. Neurophysiologic monitoring. I. Simon, Mirela V.
[DNLM: 1. Monitoring, Intraoperative--methods. 2. Neurosurgical Procedures--adverse effects.
3. Diagnostic Techniques, Neurological. 4. Intraoperative Complications--prevention & control.
WL 368 I613 2010]
RD52.N48I555 2010
616.85’2--dc22
2009040425
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Made in the United States of America
09 10 11 12 13 5 4 3 2 1
To my son, Siddharth
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CONTENTS
Preface xi
Acknowledgments xiii
Contributors xv
1. Neurophysiologic Tests Used in the 3. Electrocorticography 95
Operating Room 1 Mirela V. Simon, Jason L. Gerrard, and
Mirela V. Simon Emad N. Eskandar
I. Introduction 1 I. Introduction 95
II. Electroencephalogram (EEG) 1 II. Historical Perspective 95
III. S hort-latency Somatosensory Evoked III. T he Controversial Role of ECoG in
Potentials (SSEPs) 5 Epilepsy Surgery 96
IV. Motor Evoked Potentials (MEPs) 16 IV. Indications 98
V. F ree-Run and Triggered EMG (fEMG and V. Methodology 115
CMAPs) 27
VI. Interpretation 117
VI. N erve-to-Nerve or Nerve Action Potentials
VII. Anesthesia Considerations 124
(NAPs) Recordings 33
VIII. Concluding Remarks 127
VII. B rainstem Auditory Evoked Potentials
(BAEPs) 37 References 127
VIII. Combinations of Tests 41
IX. Safety Issues 42 4. Functional Cortical Mapping 131
Mirela V. Simon, Donald C. Shields, and
References 44
Emad N. Eskandar
I. Introduction 131
2. EEG Monitoring During Carotid
II. Surgical Preparation 132
Endarterectomy 47
III. Sensorimotor Mapping 133
Mirela V. Simon and Keith H. Chiappa
IV. Language Mapping 149
I. Introduction 47
V. Cortical Mapping Threshold
II. Principles of Monitoring CEAs 47
Variability 155
III. Methods 66
VI. E CoG During Functional
IV. Interpretation 72 Mapping 157
References 91 VII. Anesthesia Considerations 173
viii Contents
VIII. Conclusions 173 5D Thoracoabdominal Aneurysm
Repair 237
References 173
I. Introduction 237
II. T he Vascularization of the Spinal
5. Intraoperative Neurophysiologic
Cord 237
Monitoring and Mapping of the Spinal
Cord 177 III. O perative Techniques: Preventing Acute
Spinal Cord Ischemia 240
Mirela V. Simon, Lawrence Borges, Erin S. Hart,
Brian E. Grottkau, Michael A. Peck, and IV. D elayed Neurologic Events and Surgical
Mark F. Conrad Outcomes 261
5A I ntramedullary Spinal Cord Tumor V. Conclusion 262
Resection 177
References 263
I. Introduction 177
II. T he Role of Intraoperative
Neurophysiology 177 6. Peripheral Nerve Surgery 267
Jean-Valerie C. E. Coumans, Mirela V. Simon,
III. A Historical Perspective 178
Jason S. Cooper, and Jonathan M. Winograd
IV. Intraoperative Neurophysiologic
I. Introduction 267
Monitoring 179
II. S urgery at the Level of the Cauda Equina
References 207
and Nerve Root 268
5B Decompressive Surgery of the Spine 209
III. Nerve Tumor Surgery 279
I. Introduction 209
IV. Never Injury Surgery 284
II. Intraoperative Neurophysiologic
V. Anesthesia Considerations 297
Monitoring: A Step-By-Step
Approach 210 References 297
References 220
5C Spine Deformity Surgery 223 7. Intraoperative Neurophysiologic
Monitoring of the Cranial Nerves
I. Introduction 223
and Brainstem 299
II. Surgical Indications 224 Wael F. Asaad, Mirela V. Simon, and
Emad N. Eskandar
III. T he Nuts and Bolts of Deformity
Surgery 224 I. Introduction 299
IV. T he Role of Intraoperative II. Midbrain 301
Neurophysiology 225
III. Pons 303
V. Intraoperative Neurophysiologic
IV. Medulla 317
Monitoring: A Step-By-Step
Approach 226 V. Anesthesia Considerations 321
VI. Conclusion 234 VI. Conclusions 321
References 234 References 321
Contents ix
8. The Effects of Anesthetics on Intraoperative VII. Etomidate 329
Neurophysiology Studies 325
VIII. Ketamine 329
Mirela V. Simon
IX. Dexmedetomidine 330
I. Introduction 325
X. Muscle Relaxants 330
II. Benzodiazepines 325
XI. E ffects on Peripheral Nervous System and
III. Barbiturates 326
Cranial Nerve Monitoring 332
IV. Propofol 326
References 332
V. Narcotics 327
VI. Inhalational Agents 328 Index 335