Special Thank You NO DISCLOSURES. Objectives. Pelvic Floor Dysfunction Role of Ultrasound Text

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1 Special Thank You Pelvic Floor Dysfunction Role of Ultrasound Phyllis Glanc Sunnybrook Health Sciences Center Department Medical Imaging Associate Professor, University of Toronto Professor Hans Peter Dietz generously permitted educational use of images Wonderful Sunnybrook staff who have developed a pelvic floor imaging program. NO DISCLOSURES Text Hello, incontinence helpline - can you hold? Objectives Background What are the Issues in Pelvic Floor Dysfunction Urinary (UI) & Fecal Incontinence (FI) Pelvic Organ Prolapse (POP) Levator ani trauma Post operative - Slings and Things Conclusion 1

2 Pelvic Floor Imaging - Choices TPUS Why Now? Transperineal ultrasound (TPUS) Endoanal ultrasound ( gold standard AS) MRI with rectal contrast dynamic; defecography ( limited availability) Fleuroscopic Techniques - Traditional Voiding cystourethrography (VCUG), dynamic cystoprotography, Fluoroscopic Defecography US imaging pelvic floor available many years Why Now? 3D/4D obstetrical image has made physicians comfortable with the tools Improved resolution MPR real-time with cineloops/volumes can review Tomographic CT style slices Fleuroscopy is out of favor MRI expensive Pelvic Floor Dysfunction Why Bother? Affect 50% women by age 50 1/10 have surgery by age 70 1/3 repeat surgeries Pelvic organ prolapse (POP) affect 1/3 PMW Societal costs in billions for UI and millions for POP and AI Project huge demand increase service Pelvic Floor Disorders Challenges Pelvic floor anatomy complex Requires advanced US imaging techniques Limited FOV as compared to MRI 2

3 Risk Factors * Female gender ** prolonged 2nd stage labor (vaginal delivery Plus Increasing age Pelvic surgery - especially hysterectomy Chronic increased abdominal pressure eg obesity, weight lifting, Poor pelvic support Connective tissue disorders, post radiation Compartments Pelvic Floor Anterior - Bladder, urethra Central - Uterus-cervix-vagina Posterior - Anal sphincter and rectum Level Anterior compartment Reference Slide Posterior Compartment 1 Highest Bladder base Inferior 1/3 rectum 2 Mid Bladder neck Anorectal junction Anatomy Review Urethra anal canal 3 Low Midurethra Upper 1/3 anal canal Levator Ani Sling -Lateral vagina -Posterior Anal canal -Attach PR anterior 4* Lowest Distal urethra Mid/lower 1/3 anal canal Perineal body & superficial perineal muscles (perineal muscles, bulbospongiosus, ischiocavernosus,superficial transverse Uterus Cervix rectum * Level measure AP diameter UG hiatus ( pubosymphysis-perineal body distance) 11 3

4 Urinary Incontinece Women more susceptible Anatomy : Urethra shorter thus less resistance to outflow when bladder contracts Life style Risks: Vaginal Delivery/2 nd stage labor prolonged Urinary Incontinence Stress : (SUI) -increase abdominal pressure (cough, laugh, sneeze) results involuntary loss urine Sphincteric defect / hypermobility urethra Urge urinary incontinence (UUI) - detrusor overactivity ( destrusor thickness > 5mm) or damage innervation bladder Overflow: Leakage Anterior Compartment: UI & Prolapse Key role of Ultrasound Bladder neck remains closed Hypermobility urethra descends & rotates horizontal Borderline small cystocele develops ID position bladder neck / urethra, assess PVR Assess UVJ for rotation and descent -maintain RVA (retrovesical angle > 120 degrees) Assess develop cystocele ( if UVJ stable may kinked urethra and bladder dysfuntion/retention Distinguish between cystocele with urethral hypermobility versus a cystocele without urethral rotation Rest Strain Classic SUI 4

5 Retrovesical angle now > 120 degrees Associated SUI Isolated Cystoceles - Less common - Bladder neck remains in place - Voiding dysfunction rather than SUI - Association with levator ani trauma Posterior Compartment Posterior Compartment Anal continence - Anorectal angle degrees rest & anorectal junction above or at level PS POP with perineal hypermobility - descent rectal ampulla Rectovaginal defect with diverticular outpouching anterior wall rectum into vagina is rectocele, also sigmoidocele, enterocele Rectal intussception EAUS gold standard assess anal sphincter Distinguish incontinent patients with intact anal sphincter vs sphincteric lesions (defect, scarring, atrophy) 90% sensitivity/specificity MRI good big picture/muscles Anal sphincter trauma 5

6 Important to have maximum effort Rest normal ARA which is above pubic symphysis Valsalva develop rectocele, loss acute ARA, descent rectal ampulla Development sigmoidocele Rectocele measure depth perpendicular to wall expected contour anterior rectal wall in continuity with AS > cm Fecal Incontinence TPUS: Normal AS Not the Gold Standard TPUS - Anal Sphincter Useful for rapid assessment AS but more importantly bigger picture thinking puborectalis / levator tears, abnormal RVA and dev rectocele/enterocele/sigmoidocele IAS =2-3mm, EAS variable thickness US sensitivity/specificity muscular defect ~ 90% Pannu et al Radiographics 2010 Yagel et al., Valsky et al., UOG 2006, 2 6

7 TPUS Anal Sphincter Results less validated c/w endoanal US PELVIC ORGAN PROLAPSE Courtesy Dr. Dietz Pelvic Organ Prolapse (POP) Descent of the pelvic organs beneath a theoretical line between PS and ARA Cystocele bladder Rectocele anterior wall rectum Into widened rectovaginal space is enterocele or sigmoidocele Vaginal prolapse or pocidentia (uterus) Critical pre surgery to evaluate all compartments Pelvic Organ Prolapse (POP) 9% women clinical symptoms 30% undergo repeat operation Negative impact on quality of life including sexual function LA avulsion from pubic bone or pelvic sidewall is associated with POP LA avulsion is associated with vaginal delivery Also important to recognize only important if clinically symptomatic 7

8 MR - Pubococcygeal line Pelvic Organ Prolapse (Anterior) Pelvic Organ Prolapse (posterior) 3D & Volume Rendered Critical Pelvic Organ Prolapse ( Posterior) Line from PS to ARA at rest.. Dimensions urogenital hiatus POP Levator Ani Trauma Slings and Things 8

9 Display Modes : MPR/Rendered MPR/orthogonal display mode shows crosssectional planes through the volume in question. Imaging planes on 3D US can change either at the time of acquisition or offline at a later time. D = standard rendered image of the levator hiatus, with the rendering direction set from caudally to cranially Urogenital Diaphragm Largest natural hiatus in body Mean 16 cm young nullip Mean 25 cm overall Most caudal layer pelvic floor Composed of CT and peroneus muscle run from ischial rami to perineal body and EAS Perineal body is site attachment for endopelvic fascia, UG diaphragm, bulbocavernosus muscle and puborectalis muscle Courtesy Dr. Dietz Urogenital Hiatus Biometric Indices: AP diameter cm laterolateral diameter cm hiatal area cm Urogenital hiatal ballooning on Valsalva Functional Assessment Valsalva and PFMC allow its functional assessment. Ballooning of the hiatus(excessive distensibility of LA) increase in hiatal area to > 25 cm 2 on Valsalva maneuver Generally associated with full pelvic organ prolapse (POP) Dietz et al and Santoro et al. 9

10 Levator Avulsion Common ( 10-35%) post vaginal delivery Forceps triple risk Will result Reduction contraction strength Increased risk prolapse (ant/central) 2-3x Increased risk prolapse recurrence post surgery May not affect SUI or FI Pelvic Floor Musculature Levator ani muscles symmetric broad muscular sheet attached internal surface pelvis Key point maintain constant tone except during voiding, defecation, Valsalva Stretched during vaginal delivery with maximal strain occuring in most medial aspect pubococcygues Levator Ani (LA) Avulsion Direct signs is the avulsion of LA Indirect sign is the disruption of H configuration vagina suggested by posterior displacement vaginal fornix Normal Levator ani ( puborectalis) avulsion Dietz and Lanzarone, Obstet Gynecol 2005; Dietz et al. IUGJ 2010 TUI :Right-side levator ani defect measure ~ 2 cm (AP) retraction muscle 10

11 Slings Mesh Suburethral Concept: Continence maintained at midurethra instead of the bladder neck Failure of the pubourethral ligaments Propylene mesh pore size minimum 75 microns Permit entry macrophages, fibroblasts, collagen fibres Complications Mesh erosion rate ~ 9% Bleeding pv 31% TVT Mesh Pain 13% Voiding dysfunction 21% PS - Mesh gap in Valsalva < 1cm < 7mm increase probability functional obstruction thus may consider tape division 20% mesh arm dislodge - mesh mobile Line straight or obtuse, wide gap? not anchored Mesh can fold up into itself, migrate, perforate Warning: FDA and mesh July 2011 Concern re use of mesh in prolapse surgery 70,000 such procedures done in the US /yr TVT (tensionless vaginal tape TOT (Transobturator tape Repair via obturator foramen for anchoring may be useful for women with levator avulsion injuries to decrease risk recurrence Complications are attracting the attention of lawyers soliciting for class action lawsuits. Concern for surgeons if they should stop New evidence show that they markedly reduce recurrence rates (Altman et al, NEJM 2011, Wong IUGJ 2011) 11

12 Conclusion: FDA & MESH Mesh use in patients at high risk of recurrence is approriate Age (the younger the worse), prolapse stage, previous failed surgery, levator avulsion Inciting factors ( obesity...) Mesh use in patients at low recurrence risk? Newer studies demonstrate higher rate of treatment success Sagittal Mesh midurethral level Harder to obtain information but doable TOT Axial view Relatively straight extending laterally to insert on puborectalis/levator ani and out thru obturator foramen *Whiteside AJOG 2004, Vakili AJOG 2005, Dietz UOG 2010, Model EJOGRB 2010, Wong IUGJ 2011, Morgan IJGO 2011, Weemhoff IUGJ 2011, Narrow gap < 7mm Evaluation TOT PS- Mesh Gap Too Narrow Problem: Voiding Dysfunction Typically > 1cm Typically cut mesh to cure this PS Mesh Gap Too wide/high PROBLEM: Recurrent UI Mesh high in location Bladder neck opens wide with stress although remains fixed high in position 12

13 Problem Post-Operative Urinary Dysfunction Cut Sling Problem Post-Operative - Pain Tomographic Slice Courtesy Dr. Dietz TVT curve anchoring anterior, deshiscient Mesh frayed & migrated into vagina. Rendered Image Problem Post Operative TVT perforation / migration into urethra TVT curve anchoring anterior, the left side is split in two and not obviously anchored, concern Edges migrated into vagina. Courtesy Dr. Dietz 13

14 Conclusion Pelvic floor disorders common Complex area Best for POP, LA avulsion defects, hiatal ballooning, SUI Biofeedback pelvic floor contraction Does not always correlate well with clinical symptoms More research needed References State of the art: an integrated approach to pelvic floor ultrasonography. H. P. Dietz 3, Ultrasound in Obstetrics & Gynecology 37, , April 2011 DeLancey JO. The hidden epidemic of pelvic floor dysfunction: achievable goals for improved prevention and treatment. Am J Obstet Gynecol 2005; 192: Dietz HP, Shek C, Clarke B. Biometry of the pubovisceral muscle and levator hiatus by three-dimensional pelvic floor ultrasound. Ultrasound Obstet Gynecol 2005; 25: Lekskulchai O, Dietz H. Detrusor wall thickness as a test for detrusor overactivity in women. Ultrasound Obstet Gynecol 2008; 32: Broekhuis SR, Futterer JJ, Hendriks JCM, Barentsz JO, Vierhout ME, Kluivers KB. Symptoms of pelvic floor dysfunction are poorly correlated with findings on clinical examination and dynamic MR imaging of the pelvic floor. Int Urogynecol J 2009; 20: Model A, Shek KL, Dietz HP. Do levator defects increase the risk of prolapse recurrence after pelvic floor surgery? Neurourol Urodyn 2009; 28: Dietz HP, Haylen BT, Broome J. Ultrasound in the quantification of female pelvic organ prolapse. Ultrasound Obstet Gynecol 2001; 18: Yagel S, Valsky DV. Three-dimensional transperineal ultrasonography for evaluation of the anal sphincter complex: another dimension in understanding peripartum sphincter trauma. Ultrasound Obstet Gynecol 2006; 27: Dietz HP, Barry C, Lim YN, Rane A. Two-dimensional and three-dimensional ultrasound imaging of suburethral slings. Ultrasound Obstet Gynecol 2005; 26: Dietz HP, Steensma AB. Posterior compartment prolapse on two-dimensional and three-dimensional pelvic floor ultrasound: the distinction between true rectocele, perineal hypermobility and enterocele. Ultrasound Obstet Gynecol 2005; 26: