Imaging Pelvic Floor Disorders (eBook)

Foreword 5
Preface 6
Table of contents 7
1 The Anatomy of the Pelvic Floor and Sphincters 9
1.1 Introduction 9
1.2 Embryology 10
1.2.1 Cloaca and Partition of the Cloaca 10
1.2.2 Bladder 11
1.2.3 Urethra 11
1.2.4 Vagina 11
1.2.5 Anorectum 12
1.2.6 Pelvic Floor Muscles 12
1.2.7 Fascia and Ligaments 12
1.2.8 Perineum 12
1.2.9 Newborn 12
1.3 Anatomy 13
1.3.1 Pelvic Wall 13
1.3.1.1 Tendineus Arcs 15
1.3.2 Pelvic Floor 16
1.3.2.1 Supportive Connective Tissue (Endopelvic Fascia) 16
1.3.2.1.1 Endopelvic Fascia 16
1.3.2.2 Pelvic Diaphragm 16
1.3.2.2.1 Coccygeus Muscle 16
1.3.2.2.2 Levator Ani Muscle 16
1.3.2.3 Perineal Membrane (Urogenital Diaphragm) 17
1.3.2.4 Superfi cial Layer (External Genital Muscles) 18
1.3.2.4.1 Transverse Perineal Muscles 19
1.3.3 Bladder 20
1.3.3.1 Detrusor 21
1.3.3.2 Adventitia 21
1.3.3.3 Bladder Support 21
1.3.3.4 Neurovascular Supply 21
1.3.4 Urethra and Urethral Support 22
1.3.4.1 Female Urethra 22
1.3.4.1.1 Urethral Mucosa 22
1.3.4.1.2 Smooth Muscle Urethral Coat 22
1.3.4.1.3 External Urethral Sphincter 23
1.3.4.2 Male Urethra 23
1.3.4.2.1 Lining of the Male Urethra 23
1.3.4.2.2 Preprostatic Urethra 23
1.3.4.2.3 Prostatic Urethra 24
1.3.4.2.4 Membranous Urethra and Spongiose Urethra 24
1.3.4.3 Urethral Support 24
1.3.5 Uterus and Vagina 26
1.3.5.1 Uterus and Vaginal Support 26
1.3.6 Perineum and Ischioanal Fossa 27
1.3.6.1 Perineal Body 27
1.3.6.2 Ischioanal Fossae 27
1.3.6.3 Perianal Connective Tissue 28
1.3.7 Rectum 28
1.3.7.1 Rectal Wall 29
1.3.7.2 Rectal Support 29
1.3.7.3 Neurovascular Supply of the Rectum 29
1.3.8 Anal Sphincter 29
1.3.8.1 Lining of the Anal Canal 30
1.3.8.2 Internal Anal Sphincter 31
1.3.8.3 Intersphincteric Space 31
1.3.8.4 Longitudinal Layer 31
1.3.8.5 External Anal Sphincter 31
1.3.8.6 Pubovisceral (Puborectal) Muscle 33
1.3.8.7 Anal Sphincter Support 33
1.3.8.8 Anal Sphincter Anatomy Variance and Ageing 33
1.3.8.9 Neurovascular Supply of the Anal Sphincter 34
1.3.9 Nerve Supply of the Pelvic Floor 35
1.3.9.1 Somatic Nerve Supply 35
1.3.9.2 Autonomic Nerve Supply 35
References 35
2 Functional Anatomy of the Pelvic Floor 38
2.1 Introduction 38
2.2 Support of the Pelvic Organs 38
2.2.1 Endopelvic Fascia 39
2.2.2 Uterovaginal Support 40
2.2.3 Apical Prolapse Uterus or Vaginal Apex
2.2.4 Anterior Wall Support and Urethra 42
2.2.5 Posterior Support 44
2.2.6 Levator Ani Muscles 45
2.2.7 Pelvic Floor Muscles and Endopelvic Fascia Interactions 46
2.2.8 Perineal Membrane and External Genital Muscles 47
2.3 Functional Anatomy of the Lower Urinary Tract 47
2.3.1 Bladder 47
2.3.1.1 Vesical Neck 49
2.3.2 Urethra 49
2.3.2.1 Striated Urogenital Sphincter 49
2.3.2.2 Urethral Smooth Muscle 49
2.3.2.3 Submucosal Vasculature 49
2.3.2.4 Glands 49
References 49
3 Pelvic Floor Muscles-Innervation, Denervation and Ageing 51
3.1 Introduction 51
3.2 Innervation and Neural Control 51
3.2.1 Somatic Motor System 52
3.2.2 Sensory Control 53
3.2.3 Sensory-Motor Integration in PFM Control 54
3.2.4 Neural Control Manifesting as PFM Activity Patterns 55
3.3 Neural Control of Sacral Functions 57
3.3.1 Lower Urinary Tract Function and PFM 58
3.3.2 Anorectal Function and PFM 58
3.3.3 Sexual Behaviour and PFM 59
3.4 Ageing and PFM Changes 59
3.5 Vaginal Delivery and Neuromuscular Injury 61
3.6 Conclusion 62
References 63
4 Imaging Techniques 66
4.1 Evacuation Proctography and Dynamic Cystoproctography 66
4.1.1 Evacuation Proctography 66
4.1.1.1 Introduction 66
4.1.1.2 Technique 66
4.1.1.3 Normal Findings 68
4.1.1.3.1 Pre-Evacuation 68
4.1.1.3.2 Evacuation 69
4.1.1.3.3 Post-Evacuation 70
4.1.1.3.4 Additional Manoeuvres 70
4.1.1.3.5 Radiological Report 70
4.1.1.4 Alternative Approaches 70
4.1.2 Dynamic Cystoproctography 71
4.1.2.1 Introduction 71
4.1.2.2 Technique 71
4.1.2.3 Normal Findings and Defi nition of Prolapse 72
4.1.2.3.1 Rectocoele 73
4.1.2.3.2 Cystocoele 73
4.1.2.3.3 Enterocoele and Sigmoidocoele 74
4.1.2.3.4 Peritoneocoele 76
4.1.2.3.5 Vaginal Vault Prolapse 76
4.1.2.4 Comparison with Physical Examination 76
4.1.3 Summary 77
References 77
4.2 Dynamic MR Imaging of the Pelvic Floor 79
4.2.1 Abstract–Role of MR in Evaluating Pelvic Floor Disorders 79
4.2.2 Spectrum of MR Imaging for Pelvic Floor Disorders 79
4.2.3 Dynamic MR Proctography Technique 80
4.2.3.1 Patient Instruction 80
4.2.3.2 Patient Preparation and Positioning 80
4.2.3.3 MR Technique 81
4.2.4 Exam Interpretation 81
4.2.4.1 Bladder and Urethra 82
4.2.4.2 Vaginal, Uterus and Defects in Recto-Vaginal Fascia 83
4.2.4.3 Puborectalis Function 83
4.2.4.4 Rectal Abnormalities 84
4.2.4.5 Enteroceles and Peritoneoceles 88
4.2.4.6 Pelvic Floor Movement and Hernias 88
4.2.4.7 Incidental Findings 88
4.2.5 Patterns of Disease 88
4.2.6 erformance and Limitations of MR 91
4.2.7 Conclusion 91
References 91
4.3 MRI of the Levator Ani Muscle 93
4.3.1 Introduction 93
4.3.2 MRI Appearance of theNormal Levator Ani Muscles 94
4.3.2.1 Pubovisceral Muscle 95
4.3.2.2 Puborectal Muscle 97
4.3.2.3 Iliococcygeus Muscle 97
4.3.3 Levator Ani Muscle and Pelvic Floor Dysfunction 98
4.3.4 Pregnancy and Birth-Related Changes 101
4.3.5 Conclusion 102
References 104
4.4 Endoanal Ultrasound 105
4.4.1 Introduction 105
4.4.2 Technique for Endoanal Ultrasonography 106
4.4.3 Normal Anatomy 106
4.4.4 Anatomical Diff erences between Sexes 110
4.4.5 Eff ects of Ageing 110
4.4.6 Internal Anal Sphincter Abnormalities 110
4.4.7 External Anal Sphincter Abnormalities 113
4.4.8 Obstetric Trauma 114
4.4.9 Anismus, Rectocoele and Prolapse 116
4.4.10 Endoanal Ultrasound in Relation to Other Techniques 116
References 117
4.5 Pelvic Floor Ultrasound 119
4.5.1 Introduction 119
4.5.2 Equipment and Examination Technique 120
4.5.3 Anterior Compartment 121
4.5.3.1 Bladder Neck Position and Mobility 121
4.5.3.2 Funneling 123
4.5.3.3 Colour Doppler 123
4.5.3.4 Cystocele 123
4.5.3.5 Implants 123
4.5.3.6 Other Findings 124
4.5.4 Central Compartment 126
4.5.5 Posterior Compartment 126
4.5.6 The Axial Plane 127
4.5.6.1 Display Modes 128
4.5.6.2 Four-Dimensional Imaging 128
4.5.6.3 Clinical Applications 128
4.5.7 Conclusion 131
References 131
4.6 Endoanal Magnetic Resonance Imaging 134
4.6.1 Introduction 134
4.6.2 Imaging Technique 134
4.6.2.1 Coil and Patient Preparation 134
4.6.2.2 Sequences and Protocol 135
4.6.3 Normal Anatomy, Variances, and Pitfalls 135
4.6.4 Lesions of the Anal Sphincter 137
4.6.4.1 Scar Tissue and Defects 138
4.6.4.1.1 Internal Anal Sphincter 138
4.6.4.1.2 External Anal Sphincter 138
4.6.4.2 Atrophy 139
4.6.4.2.1 Internal Anal Sphincter 139
4.6.4.2.2 External Anal Sphincter 140
4.6.5 The Role of Endoanal MRI in the Diagnostic Workup 141
4.6.5.1 Comparison of Endoanal MRI versus Endoanal US 141
4.6.5.2 The Role of Endoanal MRI in Pre-Surgical Evaluation 142
4.6.5.3 The Role of Endoanal MRI in Post-Surgical Evaluation 142
4.6.5.4 The Role of External Phased-Array MRI in Fecal Incontinence 143
4.6.5.5 Comparison of Endoanal MRI versus Three-Dimensional Endoanal US in the Depiction of Atrophy 144
4.6.6 Summary 144
References 145
4.7 Urodynamics 146
4.7.1 Functions of the Lower Urinary Tract 146
4.7.2 Lower Urinary Tract Symptoms 147
4.7.3 Urodynamic Investigations 147
4.7.3.1 Frequency-Volume Charts 148
4.7.3.2 Pad Testing 148
4.7.3.3 Urofl owmetry with Ultrasound Estimation of Post-Void Residual 148
4.7.3.4 Basic Urodynamics 150
4.7.3.5 Videourodynamics 153
4.7.3.6 Ambulatory Urodynamics 155
4.7.3.7 Urethral Function Tests 156
4.7.3.8 Neuro-Physiological Investigations 156
4.7.3.9 Urodynamics of the Upper Tracts (Whitaker Test) 157
Abstract 146
Summary 158
References 158
4.8 Anorectal Physiology 160
4.8.1 Introduction 160
4.8.2 Clinical Features 160
4.8.3 Anorectal Manometry 161
4.8.3.1 Vector Manometry 162
4.8.3.2 Anal Electromyography 162
4.8.3.3 Pudendal Nerve Latency Measurement 163
4.8.4 Anal Sensation 163
4.8.5 Rectal Sensation 164
4.8.6 Colonic Transit 164
4.8.7 Conclusion 165
References 165
5 Urogenetical Dysfunction 167
5.1 Surgery and Clinical Imaging for Pelvic Organ Prolapse 167
5.1.1 Introduction 167
5.1.2 Anatomy of Support 168
5.1.3 Etiology of Prolapse 169
5.1.4 The Radiologist and the Clinician 170
5.1.5 Surgical Approach 174
5.1.6 The Anterior Vaginal Wall 175
5.1.6.1 Paravaginal Cystocele Repair 176
5.1.6.2 Graft Placement 176
5.1.6.3 Anterior Colporrhaphy 177
5.1.7 Surgery of the Vaginal Apex 178
5.1.7.1 Abdominal Sacral Colpopexy or Colpoperineopexy 178
5.1.7.2 Sacrospinous Vault Suspension 179
5.1.7.3 Uterosacral Ligament Vault Suspension 180
5.1.7.4 Obliterative Surgery 180
5.1.7.5 Uterine Preservation Procedures 181
5.1.8 The Posterior Vaginal Wall 181
5.1.8.1 Rectocele 181
5.1.8.1.1 Posterior Colporrhaphy 181
5.1.8.1.2 Defect Directed Repair of Rectocele 182
5.1.8.1.3 Graft Replacement 182
5.1.8.1.4 Imbrication 183
5.1.8.1.5 Transanal Repair 183
5.1.8.2 Enterocele 183
5.1.8.3 Prolapse Repair “Kits” 184
5.1.9 Conclusion 184
References 185
5.2 Urinary Incontinence: Clinical and Surgical Considerations 189
5.2.1 Introduction 189
5.2.1.1 Defi nition 189
5.2.1.2 Epidemiology 190
5.2.1.2.1 Prevalence of Urinary Incontinence 190
5.2.1.2.2 Risk Factors for Urinary Incontinence 190
5.2.2 Continence Mechanisms 191
5.2.3 Types of Urinary Incontinence 191
5.2.3.1 Stress Urinary Incontinence 191
5.2.3.2 Urge Urinary Incontinence 192
5.2.3.3 Overfl ow Incontinence 192
5.2.3.4 Neurogenic Urinary Incontinence 192
5.2.3.5 Extra-Urethral Incontinence 193
5.2.4 Clinical Evaluation 194
5.2.4.1 Patient History 194
5.2.4.2 Validated Questionnaires 195
5.2.4.3 Physical Examination 195
5.2.4.4 Additional Tests 195
5.2.4.5 Imaging 197
5.2.5 Treatment of Stress Incontinence 198
5.2.5.1 Conservative Treatment 198
5.2.5.1.1 Habit Training 198
5.2.5.1.2 Mechanical Devices 198
5.2.5.1.3 Specialized Pelvic Physiotherapy 198
5.2.5.1.3.1 Pelvic Floor Muscle Training 198
5.2.5.1.3.2 Biofeedback Therapy 199
5.2.5.1.4 Drug Treatment 199
5.2.5.2 Surgical Therapy 199
5.2.5.2.1 Anterior Colporraphy 199
5.2.5.2.2 Needle Urethropexy 200
5.2.5.2.3 Abdominal Retropubic Urethropexy(Colposuspension) 200
5.2.5.2.4 Suburethral Sling 200
5.2.5.2.5 Minimally Invasive Midurethral Sling 200
5.2.5.2.6 Urethral Bulking Agents 201
5.2.5.2.7 Artifi cial Urethral Sphincter 201
5.2.6 Treatment of Urge orNeurogenic Urinary Incontinence 202
5.2.6.1 Conservative Treatment 203
5.2.6.1.1 Behavior Therapy 203
5.2.6.1.2 Bladder Training 203
5.2.6.1.3 Pelvic Floor Muscle Training 204
5.2.6.1.4 Neurostimulation 204
5.2.6.1.5 Peripheral Neuromodulation 204
5.2.6.1.6 Medical Treatment 205
5.2.6.2 Surgical Treatment 205
5.2.6.2.1 Botulinum Toxin Injections 206
5.2.6.2.2 Sacral Neuromodulation 206
5.2.6.2.3 Bladder Augmentation 206
5.2.6.2.4 Bladder Replacement–Urinary Diversion 208
6 Coloproctological Dysfunction 212
6.1 Constipation and Prolapse 212
6.1.1 Introduction 212
6.1.2 Constipation 212
6.1.3 Investigation 213
6.1.4 Evacuation Proctography and Constipation 216
6.1.4.1 Rectal Prolapse 216
6.1.4.2 Pelvic Floor Descent 219
6.1.4.3 Rectocele 221
6.1.4.4 Functional Disorder 222
6.1.5 Summary 225
References 226
6.2 Investigation of Fecal Incontinence 229
6.2.1 Introduction 229
6.2.2 Tests of Function 229
6.2.2.1 Anal Manometry 229
6.2.2.2 Rectal Balloon Expulsion 233
6.2.2.3 Rectal and Anal Sensation 233
6.2.2.4 Rectal Compliance and Capacity 234
6.2.2.5 Pudendal Nerve Terminal Motor Latency(PNTML) 235
6.2.2.6 Needle Electromyography (EMG) of the External Sphincter 236
6.2.3 Tests of Structure 237
6.2.3.1 Endoanal Ultrasound (EUS) 237
6.2.4 Tests of Structure and Function 237
6.2.4.1 Dynamic Proctography (Defecography) 237
6.2.4.2 Pelvic MRI 239
6.2.5 Anorectal Testing: Utility and Caveats 239
6.2.6 Summary 241
References 241
6.3 Surgical Management of Fecal Incontinence 244
6.3.1 Introduction 244
6.3.2 Etiology 245
6.3.3 Clinical Approach 247
6.3.3.1 History 247
6.3.3.2 Physical Examination 247
6.3.4 Investigation 247
6.3.4.1 Physiologic Studies 247
6.3.4.1.1 Imaging 248
6.3.5 Management of Fecal Incontinence 249
6.3.5.1 Conservative Management 249
6.3.5.2 Surgical Management of Fecal Incontinence 249
6.3.5.3 Sphincter Repair 250
6.3.5.4 Overlapping Anterior Sphincteroplasty 250
6.3.5.4.1 Technique 250
6.3.5.5 Artifi cial Bowel Sphincter 251
6.3.5.5.1 Technique 252
6.3.5.6 Muscle Transposition – Graciloplasty 253
6.3.5.6.1 Technique 254
6.3.5.7 Harvesting the Gracilis Muscle 254
6.3.5.8 Preparing the New Position 254
6.3.5.9 Attaching the Electrical Source 254
6.3.5.10 Sacral Nerve Stimulation 255
6.3.5.11 Mechanism of Action 255
6.3.5.11.1 Technique 256
6.3.5.12 Injectable Bulking Agents for the Anal Sphincter 257
6.3.5.12.1 Technique 257
6.3.5.13 Radiofrequency 258
6.3.5.13.1 Technique 259
6.3.6 Conclusion 259
References 260
Subject Index 264
List of Contributors 271