Main description:

Clinical Neurophysiology has evolved into a subspecialty internationally. In India, the electrophysiological studies often have to be undertaken by the clinicians themselves or by dedicated neurophysiologists. Recent advances in clinical neurophysiology and valuable feedback from the clinicians and students prompted to revise and modify this book. Most of the clinical reports and illustrations in this book are from the authors' published papers and personally managed patients. It is hoped that this book would continue to interest the readers and would translate into better patient management and meaningful research.

Salient Features

Provides the correct methodology and proper standardization of techniques lucidly
Presents the normal values of different tests for ready reference and comparison
Updated all the chapters--especially, neuropathy, myopathy, transcranial magnetic stimulation, cognitive evoked potential, and pediatric electrodiagnostic studies have been revised extensively

Inclusion of new images, tables, and learning points at the end of each chapter make the topics easy to understand and reader friendly

Contents:

xi

Preface to the Third Edition vii

Preface to the First Edition ix

1. History of Clinical Neurophysiology

Classic Electrodiagnosis 2

Electromyography and Nerve Stimulation Technique 4

Evoked Potentials 6

Miscellaneous 7

References 7

2 . An Introduction to Electrodiagnostic Signals

and Their Measurements

Biophysics 11

Electrodes 11

Filter 13

Amplifi er 14

Averager 15

Display 15

Gain and Sweep Time 16

Signal Trigger and Delay Line 17

Stimulator 17

Referral Process 18

References 19

3 . Nerve Conduction Study

3.1. Principles of Nerve Conduction Study 21

Anatomy and Physiology 21

Axonal Transport 22

Impulse Propagation 23

Principles of Motor Nerve Conduction 24

Principles of Sensory Nerve Conduction 25

Variables Affecting the Nerve Conduction Study 27

References 29

3.2. Median Nerve 30

Anatomy 30

Nerve Conduction Study 30

Median Nerve Entrapment Syndromes 31

References 37

3.3. Ulnar Nerve 38

Anatomy 38

Nerve Conduction Study 38

Ulnar Neuropathy 40

References 44

3.4. Radial Nerve 45

Anatomy 45

Nerve Conduction Study 45

Radial Neuropathy 46

References 49

3.5. Brachial Plexus 50

Anatomy 50

Brachial Plexopathy 51

Neurophysiological Assessment of Brachial Plexus Lesions 52

Thoracic Outlet Obstruction 57

Brachial Neuritis 58

Radiation-Induced Plexopathy 59

Obstetric Brachial Plexopathy 59

References 61

3.6. Cervical Radiculopathy 63

Anatomy 63

Motor and Sensory Nerve Conduction 63

F Wave 63

Somatosensory Evoked Potentials 64

Nerve Root Stimulation 64

Needle Electromyography 64

Cervical Radiculopathy 66

References 67

3.7. Lumbar Plexus and Its Terminal Branches 68

Anatomy 68

Lumbosacral Plexopathy 68

Neurophysiological Evaluation 68

References 72

3.8. Sacral Plexus and Its Terminal Nerve

Branches 73

Anatomy 73

References 81

3.9. Lumbosacral Radiculopathy 83

Anatomy 83

L 2 , L 3 , and L 4 Radiculopathies 83

L 5 Radiculopathy 83

S 1 and S 2 Radiculopathy 84

Multiple Lumbosacral Radiculopathies 84

Diagnostic Utility of EMG and MRI in Radiculopathy 85

References 86

3.10. Anomalous Innervation of the Extremities 87

Median to Ulnar Nerve Communication (Martin - Gruber

Anastomosis) 87

Ulnar to Median Nerve Communication 88

Variations in the Innervations of Intrinsic Hand Muscles 88

Accessory Deep Peroneal Nerve 88

Tibial and Peroneal Nerve Communication 89

References 89

3.11. Nerve Conduction of Nonlimb Nerves 90

Phrenic Nerve 90

Facial Nerve 91

Contents

xii CONTENTS

Hypoglossal Nerve 94

Great Auricular Nerve 95

References 95

3.12. Late Response 97

H Refl ex 97

F Wave 100

Axon Refl ex 104

References 105

3.13. Autonomic Nervous System Testing 106

Anatomical and Functional Basis 106

Autonomic Function Tests 107

References 117

4 . Electromyography

4.1. Introduction to Electromyography 119

Anatomy of Muscle 119

Types of EMG Needle Electrodes 120

Recording Technique 121

References 132

4.2. Technique of Electromyography 133

Muscles of Hands 133

Muscles of Forearm 135

Muscles of Arm 140

Muscles of Shoulder Girdle and Trunk 141

Muscle of the Foot 144

Muscles of Leg 146

Muscles of Thigh 149

Muscles of Pelvic Girdle 151

Muscles of Face, Head, and Neck 153

5 . Clinical Application of EMG and Nerve

Conduction

5.1. Electromyographic Findings in Nerologic

Disorders 157

Neurogenic Disorders 157

Myopathic Disorders 166

References 193

5.2. Nerve Conduction and EMG Studies in

Polyneuropathies 198

Pathophysiological Basis of Nerve Conduction Study 198

Conduction Block and Temporal Dispersion 199

Neurophysiological Classifi cation of Polyneuropathy 200

Limitation of Nerve Conduction Studies 202

Hereditary Neuropathies 205

Acute Infl ammatory Demyelinating Polyneuropathy 214

Chronic Infl ammatory Demyelinating Polyneuropathy 217

Subacute Idiopathic Demyelinating Polyradiculopathy 220

Motor Neuropathy with Multifocal Conduction Block or

Multifocal Motor Neuropathy 221

Neuropathy Associated with AIDS 222

Leprosy 225

Diphtheritic Neuropathy 228

Metabolic Neuropathy 228

Carcinomatous Neuropathy 233

Nutritional Neuropathy 234

Critical Care Neuropathy 235

Toxic Neuropathy 237

Drug-Induced Neuropathy 237

Ischemic Neuropathy 239

Neuropathy Associated with Connective Tissue

Disorder 240

Overview of Investigations in Neuropathy 242

References 243

6 . Repetitive Nerve Stimulation

Neuromuscular Junction 251

Physiology of RNS Test 252

Variables Infl uencing Neuromuscular Transmission 253

Technique of RNS 254

Measurement 255

Interpretation of RNS Test 257

Clinical Application of RNS Study 260

References 269

7 . Single-Fiber Electromyography

Introduction 271

Method of SFEMG 271

SFEMG in Neurologic Diseases 276

Neuromuscular Transmission Disorders 277

SFEMG in Neurogenic Disorders 278

SFEMG in Myopathies 279

Macro-EMG 280

References 280

8 . Visual Evoked Potential

Anatomical Basis of VEP 283

Methods of Visual Evoked Potential 284

Variables Infl uencing VEP 287

Clinical Applications of VEP 289

References 296

9 . Brainstem Auditory Evoked Potential

Anatomical and Physiological Basis of BAEPs 301

Brainstem Electrical Activity and Its Correlation with BAEP 301

Patient-Related Variables Affecting BAEP 302

Method 303

Normal BAEP, Potential Field Distribution, Waveform

Recognition, and Normal Values 304

Abnormal BAEP 308

Clinical Neurophysiological Correlation 308

References 314

10. Somatosensory Evoked Potentials

Anatomical and Physiological Basis of SEP 317

Methods 317

Normal Median SEP 319

Reproducibility of SEP 323

Patient-Related Factors 323

Clinical Application of SEP 324

Surgical Monitoring 334

References 335

CONTENTS xiii

11. Motor Evoked Potential

Anatomy and Physiology of Corticospinal Tract 339

Physiological Basis of Motor Evoked Potential 340

Method of Motor Evoked Potential 342

Measurement of CMCT 344

CMCT Abnormalities and Their Basis 345

Comparison of Electrical and Magnetic Stimulation 346

Safety of Transcranial Electrical and Magnetic Stimulation 347

Clinical Applications 347

References 361

12. Cognitive Evoked Potential

P 3 365

Waveform Identifi cation and Measurement 366

Variables Affecting P 3 367

Generators of P 3 368

Clinical Application 368

References 373

13. Electrodiagnosis in Pediatric Practice

13.1. Nerve Conduction and Electromyography 376

Nerve Conduction Studies 376

Sensory NCS 378

Needle EMG 379

Repetitive Nerve Stimulation 381

References 381

13.2. Visual Evoked Potential in Pediatric Practice 382

Methodology 382

Maturation of VEP 382

Measurement of VEP 383

Clinical Application 383

References 385

13.3. Brainstem Auditory Evoked Potential in Pediatric

Practice 386

Methodological Considerations 386

Maturation of BAEP 387

Clinical Application of BAEP in Pediatrics 389

References 394

13.4. Somatosensory Evoked Potentials in Pediatric

Practice 396

Methodological Considerations 396

Maturational Changes 396

Clinical Applications 397

References 400

14. Role of Clinical Neurophysiology in the Prognosis

of Neuromuscular Disorders

Amyotrophic Lateral Sclerosis 403

Radiculopathy 404

Traumatic Nerve Injury 404

Polyneuropathy 405

Diseases of Neuromuscular Junction 410

Myopathy 410

References 413

Index 417