Contents I MEDICAL RADIOLOGY Diagnostic Imaging Editors: A. L. Baert, Leuven M. Knauth, Göttingen Contents III J. Stoker · S. A. Taylor · J. O. L. DeLancey (Eds.) Imaging Pelvic Floor Disorders 2nd Revised Edition With Contributions by P. Abrams · C. I. Bartram · A. E. Bharucha · A. C. de Bruijne-Dobben · J. O. L. DeLancey H. P. Dietz · A. V. Emmanuel · J. G. Fletcher · D. S. Hale · S. Halligan · F. Housami M. Oelke · J.– P. Roovers · S. Shawki · H. Siddiki · J. Stoker · S. A. Taylor · W. H. Umek D. B. Vodušek · C. Wallner · S. D. Wexner Foreword by A. L. Baert With 212 Figures in 276 Separate Illustrations, 68 in Color and 23 Tables 123 IV Contents Jaap Stoker, MD, PhD John O. L. DeLancey, MD Professor of Radiology Norman F. Miller Professor of Gynecology Department of Radiology Director, Pelvic Floor Research Group Academic Medical Center Director, Fellowship in Female Pelvic Medicine and University of Amsterdam Reconstructive Surgery Meibergdreef 9 L4000 Women’s Hospital 1105 AZ Amsterdam University of Michigan The Netherlands 1500 E. Medical Center Drive Ann Arbor, Mi 48109-0276 Stuart A. Taylor, MD, MRCP, FRCR USA Senior Lecturer in Radiology Department of Specialist X-Ray University College Hospital 2F Podium, 235 Euston Road London NW1 2BU UK Medical Radiology · Diagnostic Imaging and Radiation Oncology Series Editors: A. L. Baert · L. W. Brady · H.-P. Heilmann · M. Knauth · M. Molls · C. Nieder Continuation of Handbuch der medizinischen Radiologie Encyclopedia of Medical Radiology ISBN 978-3-540-71966-3 e-ISBN 978-3-540-71968-7 DOI 10.1007 / 978-3-540-71968-7 Medical Radiology · Diagnostic Imaging and Radiation Oncology ISSN 0942-5373 Library of Congress Control Number: 2007942181 ¤ 2008, Springer-Verlag Berlin Heidelberg This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, s pecifi cally the rights of translation, reprinting, reuse of illustrations, recitations, broadcasting, reproduction on microfi lm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permis- sion for use must always be obtained from Springer-Verlag. Violations are liable for prosecution under the German Copyright Law. The use of general descriptive names, trademarks, etc. in this publication does not imply, even in the absence of a specifi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Product liability: The publishers cannot guarantee the accuracy of any information about dosage and application contained in this book. In every individual case the user must check such information by consulting the relevant literature. Cover Design and Layout: PublishingServices Teichmann, 69256 Mauer, Germany Printed on acid-free paper 9 8 7 6 5 4 3 2 1 springer.com Contents V Foreword Pelvic fl oor disorders represent an increasingly important clinical problem due to the aging of the population. Recent technical progress in cross-sectional imaging with ultrasound as well as with MRI now enables us to obtain totally new insights into the anatomy and pathophysiol- ogy of the complex pelvic fl oor structures. This second edition has been fully updated to represent the current state of the art and provide an excellent and comprehensive overview of the techniques to be applied in a focused study of the pelvic fl oor. It also offers expert guidance in modern manage- ment of the various clinical conditions related to the dysfunction of specifi c compo- nents of the pelvic fl oor. J. Stoker and S. A. Taylor have joined J. O. L. DeLancey as editors for this second edition. They are internationally recognized leaders in the fi eld and I am very much indebted to them for their judicious choice of topics and collaborating authors, as well as for the expedient and rapid preparation of this superb volume. I am convinced that this second edition will again be met with great interest by radi- ologists and all other clinicians involved in the care of patients with pelvic disorders. Leuven Albert L. Baert Contents VII Preface Disorders of the pelvic fl oor are very common, particularly affecting the female popu- lation. Although not life-threatening, the impact of these disorders on the quality of life of those affected cannot be understated, and indeed may be devastating. Imaging plays an important role in the management of these disorders, its utility further increased with the new and valuable insights provided by current techniques. The aim of this book is to provide those practitioners with an interest in the imag- ing, diagnosis and treatment of pelvic fl oor dysfunction with a thorough update of this rapidly evolving fi eld. As in the fi rst edition, this volume is written by a combination of radiologists and clinicians (urogynaecologists, surgeons, urologists), refl ecting the importance of a multidisciplinary approach when considering pelvic fl oor disorders in both clinical practice and research. Based on the success of the fi rst edition, edited by our friend and colleague Clive Bartram, the overall structure of this new edition remained largely unchanged. Intro- ductory chapters on anatomy and (patho)physiology are followed by chapters on state- of-the-art imaging techniques and their application in pelvic fl oor dysfunction. The closing chapters describe modern clinical management of pelvic fl oor disorders with specifi c emphasis on the integration of diagnostic and treatment algorithms. All exist- ing chapters have been rewritten or updated to refl ect the rapid developments in this fi eld, and chapters on several new topics have been added, including perineal ultra- sound and MRI of the levator muscles. We thank the contributing authors for their valuable contribution to this book. We are very fortunate to have so many distinguished experts in the fi eld contributing to this volume. Professor Baert has our thanks for his invitation to contribute a second edition of Imaging Pelvic Floor Disorders to the renowned Medical Radiology series. We also thank Ursula Davis and her colleagues at Springer for the very effective pro- duction process and polite, timely communication. Amsterdam Jaap Stoker London Stuart A. Taylor Ann Arbor John O. L. DeLancey Contents IX Contents 1 The Anatomy of the Pelvic Floor and Sphincters Jaap Stoker and Christian Wallner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 Functional Anatomy of the Pelvic Floor John O. L. DeLancey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 3 Pelvic Floor Muscles-Innervation, Denervation and Ageing David B. Vodušek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 4 Imaging Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 4.1 Evacuation Proctography and Dynamic Cystoproctography Stuart A. Taylor and Steve Halligan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 4.2 Dynamic MR Imaging of the Pelvic Floor Joel G. Fletcher, Adil E. Bharucha, and Hassan Siddiki . . . . . . . . . . . . . 75 4.3 MRI of the Levator Ani Muscle Wolfgang H. Umek and John O. L. DeLancey . . . . . . . . . . . . . . . . . . . . . . . . 89 4.4 Endoanal Ultrasound Clive I. Bartram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 4.5 Pelvic Floor Ultrasound Hans Peter Dietz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 4.6 Endoanal Magnetic Resonance Imaging Annette C. de Bruijne-Dobben and Jaap Stoker . . . . . . . . . . . . . . . . . . . . 131 4.7 Urodynamics Fadi Housami and Paul Abrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 4.8 Anorectal Physiology Anton V. Emmanuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157 5 Urogenetical Dysfunction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 5.1 Surgery and Clinical Imaging for Pelvic Organ Prolapse Douglass S. Hale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 5.2 Urinary Incontinence: Clinical and Surgical Considerations Jan-Paul Roovers and Matthias Oelke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187 X Contents 6 Coloproctological Dysfunction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 6.1 Constipation and Prolapse Steve Halligan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 6.2 Investigation of Fecal Incontinence Adil E. Bharucha . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 6.3 Surgical Management of Fecal Incontinence Steven D. Wexner and Sherief Shawki . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245 Subject Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 List of Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 The Anatomy of the Pelvic Floor and Sphincters 1 The Anatomy of the Pelvic Floor and Sphincters 1 Jaap Stoker and Christian Wallner C O N T E N T S 1.3.6 Perineum and Ischioanal Fossa 19 1.3.6.1 Perineal Body 19 1.3.6.2 Ischioanal Fossae 19 1.1 Introduction 1 1.3.6.3 Perianal Connective Tissue 20 1.2 Embryology 2 1.3.7 Rectum 20 1.2.1 Cloaca and Partition of the Cloaca 2 1.3.7.1 Rectal Wall 21 1.2.2 Bladder 3 1.3.7.2 Rectal Support 21 1.2.3 Urethra 3 1.3.7.3 Neurovascular Supply of the Rectum 21 1.2.4 Vagina 3 1.3.8 Anal Sphincter 21 1.2.5 Anorectum 4 1.3.8.1 Lining of the Anal Canal 22 1.2.6 Pelvic Floor Muscles 4 1.3.8.2 Internal Anal Sphincter 23 1.2.7 Fascia and Ligaments 4 1.3.8.3 Intersphincteric Space 23 1.2.8 Perineum 4 1.3.8.4 Longitudinal Layer 23 1.2.9 Newborn 4 1.3.8.5 External Anal Sphincter 23 1.3.8.6 Pubovisceral (Puborectal) Muscle 25 1.3 Anatomy 5 1.3.8.7 Anal Sphincter Support 25 1.3.1 Pelvic Wall 5 1.3.8.8 Anal Sphincter Anatomy Variance and 1.3.1.1 Tendineus Arcs 7 Ageing 25 1.3.2 Pelvic Floor 8 1.3.8.9 Neurovascular Supply of the 1.3.2.1 Supportive Connective Tissue Anal Sphincter 26 (Endopelvic Fascia) 8 1.3.9 Nerve Supply of the Pelvic Floor 27 1.3.2.2 Pelvic Diaphragm 8 1.3.9.1 Somatic Nerve Supply 27 1.3.2.3 Perineal Membrane 1.3.9.2 Autonomic Nerve Supply 27 (Urogenital Diaphragm) 9 1.3.2.4 Superfi cial Layer References 27 (External Genital Muscles) 10 1.3.3 Bladder 12 1.3.3.1 Detrusor 13 1.3.3.2 Adventitia 13 1.3.3.3 Bladder Support 13 1.3.3.4 Neurovascular Supply 13 1.3.4 Urethra and Urethral Support 14 1.1 1.3.4.1 Female Urethra 14 Introduction 1.3.4.2 Male Urethra 15 1.3.4.3 Urethral Support 16 The pelvic fl oor supports the visceral organs, is 1.3.5 Uterus and Vagina 18 1.3.5.1 Uterus and Vaginal Support 18 crucial in maintaining continence, facilitates mic- turition and evacuation and in women forms part of the birth canal. This multifunctional unit is a complex of muscles, fasciae and ligaments that J. Stoker, MD, PhD have numerous interconnections and connections Professor of Radiology, Department of Radiology, Academic to bony structures, organs and the fi broelastic net- Medical Center, University of Amsterdam, Meibergdreef 9, work within fat-containing spaces. A detailed appre- 1105 AZ Amsterdam, The Netherlands ciation of the pelvic fl oor is essential to understand C. Wallner, MSc Department of Anatomy and Embryology, Academic Medical normal and abnormal function. The embryology of Center, University of Amsterdam, Meibergdreef 69–71, 1105 the pelvic fl oor is included to help explain certain BK Amsterdam, The Netherlands anatomical features. 2 J. Stoker and C. Wallner The anatomy of the pelvic fl oor is described in sac 4 weeks after fertilization to form the foregut, an integrated manner, with special attention to the midgut and hindgut. A diverticulum, the allantois, connections between structures that are crucial for develops from the hindgut. The part of the hind- a proper function of the pelvic fl oor. Apart from line gut connected to the allantois is called the cloaca drawings, T2-weighted magnetic resonance imag- (Figs. 1.1, 1.2). The cloaca is joined laterally by the ing (MRI) is used to illustrate normal anatomical nephric (later mesonephric) ducts. At the angle of structures. the allantois and hindgut there is a coronal rim of The structure of the pelvic fl oor and its attach- endoderm and mesenchyme proliferation – the uro- ments to pelvic bones are an evolutionary adapta- genital septum (or cloacal septum), which develops tion to our upright position, which requires greater from the sixth week (Fig. 1.1). The septum grows in support for the abdominal and pelvic organs overly- the direction of the cloacal membrane while fork- ing the large pelvic canal opening. The initial evolu- like extensions produce lateral cloacal infolding. At tionary step was the development of a pelvic girdle, the margins of the cloacal membrane, mesenchyme as found in amphibians, which were the fi rst ver- migrates from the primitive streak to form lateral tebrates adapted to living on land. The second was (genito- or labioscrotal) folds and a midline genital adaptation of the pelvic fl oor muscles. Pelvic organ tubercle (precursor of the phallus) (Hamilton and support in early primates was controlled by contrac- Mossman 1972). By the seventh week, the urogenital tion of the caudal muscles pulling the root of the tail septum divides the endodermal lined cloaca in a forward against the perineum. With the gradual larger anterior urogenital sinus (including the vesi- introduction of upright posture and loss of the tail, courethral canal) continuous with the allantois, and this mechanism became inadequate, and further a smaller posterior anorectal canal (Bannister et adaptive changes occurred with the caudal muscles al. 1995). The nodal centre of division of the cloacal becoming more anterior, extra ligamentous support plate is the future perineal body. A recent experi- (coccygeus and sacrospinous ligament), and the ori- mental study demonstrated that the cloacal sphinc- gin of the iliococcygeus muscle moving inferiorly to ter muscles develop from migrating cells from the arise from the arcus tendineus levator ani with some embryonic hind limb muscle mass (Valasek et al. associated changes in the bony pelvis (Lansman 2005). and Robertson 1992). Partial loss of contact of the pubococcygeus with the coccyx led to the develop- ment of the pubovisceralis (puborectalis). Umbilical artery Urorectal septum Notochord Hindgut Spinal chord 1.2 Embryology The embryology of the pelvic fl oor and related struc- tures remains unclear, and new concepts are contin- Allantoic duct ually being introduced, e.g. the fusion of the urogen- Umbilical vein ital septum and cloacal membrane (N ievelstein et Ectodermal cloaca al. 1998). This brief overview may be supplemented Cloacal by more detailed texts (Arey 1966; Hamilton and membrane Mossman 1972; Moore and Persaud 1998). Endodermal cloaca Postanal gut 1.2.1 Cloaca and Partition of the Cloaca The earliest stage in the development of the pelvic Fig. 1.1. The tail end of a human embryo, about 4 weeks old. fl oor, comprising the urogenital, anorectum and Reprinted from Bannister et al. (1995, p. 206), by permis- perineal regions, is the invagination of the yolk sion of Churchill Livingstone