Principles and Practices of Laryngeal Electromyography

Preface viii Acknowledgment ix Part I Basis of Laryngeal Electromyography 1 1 Anatomy of the Larynx 3 1.1 Laryngeal Muscles 3 1.1.1 Glottic Dilator Muscles (Muscles That Abduct the Vocal Folds) 3 1.1.2 Muscles That Adduct the Vocal Folds 4 1.1.3 Vocal Fold Tension/Relaxation Muscles 6 1.1.4 Epiglottis Movement Muscles 6 1.1.5 Classification of Laryngeal Muscle Fibers 6 1.2 Laryngeal Nerves 7 1.2.1 Superior Laryngeal Nerve 7 1.2.2 Recurrent Laryngeal Nerve 7 1.2.3 Sympathetic Nerve 10 1.2.4 Anastomoses 10 1.2.5 Lower Cranial Nerves 10 References 11 2 Physiology of the Larynx 12 2.1 Phonation 12 2.1.1 Power Source 12 2.1.2 Oscillator 12 2.1.3 Resonator and Articulator 13 2.1.4 Regulatory Organs 13 2.2 Respiratory Function 14 2.3 Protection Function 14 2.4 Assistance Function in Swallowing 15 2.5 Larynx and Circulatory Reflex 15 2.6 Emotional Expression 15 References 15 3 Laryngeal Electromyography 17 3.1 Overview 17 3.2 Recording System and Electrode in Electromyography 19 3.2.1 Recording System 19 3.2.2 Types of Electrodes 19 3.3 Needle Electromyography 25 3.3.1 Parameters 25 3.3.2 Abnormal Electromyographic Activity 29 3.4 Laryngeal Needle Electromyography 32 3.4.1 Technique 34 3.4.2 Electromyographic Characteristics 38 3.5 Laryngeal Nerve Conduction Study 41 3.5.1 Basic Principles 42 3.5.2 Procedures 43 3.6 Characteristics of Laryngeal Evoked Potentials 44 3.7 Other Electrophysiological Examinations 47 3.7.1 Repetitive Nerve Stimulation 47 3.7.2 Single-Fiber Electromyography 49 3.7.3 Cortical Motor Evoked Potential 49 3.8 Principles and Precautions in Electromyography 50 3.8.1 Basic Principles 50 3.8.2 Safety and Precautions 50 References 51 Part II Abnormal Laryngeal Electromyographic Manifestation and Case Study 53 4 Vocal Fold Paralysis 55 4.1 Clinical Characteristics 55 4.1.1 Etiology 55 4.1.2 Pathophysiological Mechanisms 55 4.1.3 Clinical Manifestation 56 4.1.4 Diagnosis 56 4.1.5 Prognosis Evaluation 60 Case Study 61 References 71 5 Vocal Fold Paralysis with Lower Cranial Nerve Injury 72 5.1 Clinical Characteristics 72 5.1.1 Physical Signs of Lower Cranial Nerve Injury 72 5.1.2 Characteristics of Vocal Fold Paralysis with Lower Cranial Nerve Injury 73 5.2 Case Study 73 References 82 6 Mechanical Vocal Fold Immobility 83 6.1 Arytenoid Dislocation 83 6.1.1 Clinical Characteristics 83 6.1.2 Case Study 85 6.2 Posterior Glottic Stenosis 92 6.2.1 Clinical Characteristics 92 6.2.2 Case Study 92 6.3 Laryngeal Chondroma 95 6.3.1 Clinical characteristics 95 6.3.2 Case Study 96 References 99 7 Laryngeal Myopathy 100 7.1 Clinical Characteristics 100 7.2 Case Study 101 References 104 8 Myasthenia Gravis 105 8.1 Clinical Characteristics 105 8.1.1 Etiology and Pathophysiological Mechanism 105 8.1.2 Clinical Manifestation 106 8.1.3 Examination 106 8.1.4 Diagnosis and Differential Diagnosis 107 8.2 Case Study 107 References 111 9 Spasmodic Dysphonia 112 9.1 Clinical Characteristics 112 9.1.1 Etiology and Pathogenesis 112 9.1.2 Clinical Manifestations 112 9.1.3 Laryngeal Electromyography 113 9.1.4 Diagnosis and Differential Diagnosis 114 9.1.5 Treatment and Prognosis 114 9.2 Case Study 115 References 121 10 Functional Dysphonia 122 10.1 Clinical Characteristics 122 10.2 Case Study 122 References 128 Index 000