Rose Khavari

Functional magnetic resonance imaging during urodynamic testing identifies brain structures initiating micturition

PURPOSEnNormal voiding in neurologically intact patients is triggered by the release of tonic inhibition from suprapontine centers, allowing the pontine micturition center to trigger the voiding reflex. Supraspinal mechanisms of voluntary voiding in humans are just beginning to be described via functional neuroimaging. We further elucidated brain activity processes during voiding using functional magnetic resonance imaging in normal females to gain better understanding of normal voiding as well as changes that may occur in voiding dysfunction.nnnMATERIALS AND METHODSnWe screened 13 healthy premenopausal female volunteers using baseline clinic urodynamics to document normal voiding parameters. We then recorded brain activity via functional magnetic resonance imaging and simultaneous urodynamics, including the pressure flow voiding phase. After motion correction of functional magnetic resonance images we performed activation and connectivity analyses in 10 subjects.nnnRESULTSnGroup analysis revealed consistent activation areas, including regions for motor control (cerebellum, thalamus, caudate, lentiform nucleus, red nucleus, supplementary motor area and post-central gyrus), emotion (anterior/posterior cingulate gyrus and insula), executive function (left superior frontal gyrus) and a focal region in the pons. Connectivity analysis demonstrated strong interconnectivity of the pontine micturition center with many short-range and long-range cortical clusters.nnnCONCLUSIONSnOur study is one of the first reports of brain activation centers associated with micturition initiation in normal healthy females. Results show activation of a brain network consisting of regions for motor control, executive function and emotion processing. Further studies are planned to create and validate a model of brain activity during normal voiding in women.

Complex rectovaginal fistulas after pelvic organ prolapse repair with synthetic mesh: a multidisciplinary approach to evaluation and management.

Objectives The use of synthetic mesh for transvaginal pelvic organ prolapse (POP) repair is associated with the rare complication of mesh erosion into hollow viscera. This study presents a single-institution series of complex rectovaginal fistulas (RVFs) after synthetic mesh-augmented POP repair, as well as strategies for identification and management. Methods Institutional review board approval was obtained for this retrospective study. Data were collected and analyzed on all female patients undergoing RVF repair from 2000 to 2011 at our institution. Results Thirty-seven patients underwent RVF repair at our multidisciplinary center for restorative pelvic medicine. Of these, 10 (27.0%) were associated with POP repairs using mesh. The POP repairs resulting in RVF were transvaginal repair with mesh (n = 8), laparoscopic sacrocolpopexy with concomitant traditional posterior repair (n = 1), and robotic-assisted laparoscopic sacrocolpopexy (n = 1). Time to presentation was an average of 7.1 months after POP repair. Patients underwent a mean of 4.4 surgeries for definitive RVF repair, with 40% of patients requiring a bowel diversion (3 temporary ileostomies and 1 long-term colostomy). Mean follow-up time after last surgery was 9.2 months. On follow-up, 1 patient has a persistent fistula with vaginal mesh extrusion. One patient has persistent pelvic pain. Conclusions This series highlights the significant impact of synthetic mesh complications in the posterior compartment. These complications should be cautionary for synthetic graft use by those with limited experience, particularly when an alternate choice of traditional repair is available. When symptoms of RVF are present, collaboration with a colon and rectal specialist should be initiated as soon as possible for evaluation and definitive repair.

Pelvic floor dynamics during high-impact athletic activities: A computational modeling study

Background: Stress urinary incontinence is a significant problem in young female athletes, but the pathophysiology remains unclear because of the limited knowledge of the pelvic floor support function and limited capability of currently available assessment tools. The aim of our study is to develop an advanced computer modeling tool to better understand the dynamics of the internal pelvic floor during highly transient athletic activities. Methods: Apelvic model was developed based on high‐resolution MRI scans of a healthy nulliparous young female. A jump‐landing process was simulated using realistic boundary conditions captured from jumping experiments. Hypothesized alterations of the function of pelvic floor muscles were simulated by weakening or strengthening the levator ani muscle stiffness at different levels. Intra‐abdominal pressures and corresponding deformations of pelvic floor structures were monitored at different levels of weakness or enhancement. Findings: Results show that pelvic floor deformations generated during a jump‐landing process differed greatly from those seen in a Valsalva maneuver which is commonly used for diagnosis in clinic. The urethral mobility was only slightly influenced by the alterations of the levator ani muscle stiffness. Implications for risk factors and treatment strategies were also discussed. Interpretation: Results suggest that clinical diagnosis should make allowances for observed differences in pelvic floor deformations between a Valsalva maneuver and a jump‐landing process to ensure accuracy. Urethral hypermobility may be a less contributing factor than the intrinsic sphincteric closure system to the incontinence of young female athletes. HighlightsPelvic floor deformation during jump‐landing was studied with finite‐element method.Pelvic floor deformation during jump‐landing differs from that following a Valsalva maneuver.Reduced stiffness of levator ani muscle plays a small role in causing urethral hypermobility.Failure of urethral closure system may be the main factor for athletic incontinence.

Assessment of urethral support using MRI-derived computational modeling of the female pelvis

Introduction and hypothesisThis study aimed to assess the role of individual anatomical structures and their combinations to urethral support function.MethodsA realistic pelvic model was developed from an asymptomatic female patient’s magnetic resonance (MR) images for dynamic biomechanical analysis using the finite element method. Validation was performed by comparing simulation results with dynamic MR imaging observations. Weaknesses of anatomical support structures were simulated by reducing their material stiffness. Urethral mobility was quantified by examining urethral axis excursion from rest to the final state (intra-abdominal pressureu2009=u2009100xa0cmH2O). Seven individual support structures and five of their combinations were studied.ResultAmong seven urethral support structures, we found that weakening the vaginal walls, puborectalis muscle, and pubococcygeus muscle generated the top three largest urethral excursion angles. A linear relationship was found between urethral axis excursions and intra-abdominal pressure. Weakening all three levator ani components together caused a larger weakening effect than the sum of each individually weakened component, indicating a nonlinearly additive pattern. The pelvic floor responded to different weakening conditions distinctly: weakening the vaginal wall developed urethral mobility through the collapsed vaginal canal, while weakening the levator ani showed a more uniform pelvic floor deformation.ConclusionsThe computational modeling and dynamic biomechanical analysis provides a powerful tool to better understand the dynamics of the female pelvis under pressure events. The vaginal walls, puborectalis, and pubococcygeus are the most important individual structures in providing urethral support. The levator ani muscle group provides urethral support in a well-coordinated way with a nonlinearly additive pattern.

A modification to augmentation cystoplasty with catheterizable stoma for neurogenic patients: technique and long-term results.

OBJECTIVEnTo evaluate the use of a modified Indiana continent urinary reservoir, the Indiana augmentation cystoplasty (IAC), for patients with neurogenic bladder (NGB). NGB with incontinence can be devastating for patients with neurologic illness. Augmentation cystoplasty with a continent catheterizable stoma creates a continent, low-pressure storage system, with catheterizable cutaneous stoma, leading to decreased urinary tract morbidity and increased quality of life.nnnMETHODSnRetrospective chart review of the IAC procedure in a single center from 1993 to 2010 was performed and included subjects with NGB and minimum 1-year follow up. Patients demographics, NGB diagnosis, surgery details, urodynamic findings, concurrent operations, complications, and continence outcomes were recorded.nnnRESULTSnThirty-four patients met the inclusion criteria. Mean age at time of surgery was 39.8 years. Neurologic diagnoses included multiple sclerosis (n = 12), spina bifida (n = 9), and spinal cord injury (n = 14). Concurrent surgeries included: bladder neck closure (n = 3), pubovaginal sling (n = 4), hysterectomy (n = 3), artificial urinary sphincter (n = 1), and cystolithotomy (n = 1). Mean estimated blood loss was 461.8 mL. Short-term postoperative complications were prolonged ileus (n = 2), wound infection (n = 1), and transfusion (n = 1). Median follow-up was 31 months. Long-term complications occurred in 15 (44.1%) patients: recurrent urinary tract infections (n = 4), pyelonephritis (n = 1), pelvic abscess (n = 1), seroma (n = 1), bladder stones (n = 2), and stomal revision in (n = 4). All patients were continent at latest follow-up.nnnCONCLUSIONnThis modification of the Indiana continent urinary reservoir is an excellent surgical option providing a low-pressure reservoir with a reliable continence mechanism and easily catheterizable stoma, with few complications or need for reoperation.

The Single-Incision Sling to Treat Female Stress Urinary Incontinence: A Dynamic Computational Study of Outcomes and Risk Factors

Dynamic behaviors of the single-incision sling (SIS) to correct urethral hypermobility are investigated via dynamic biomechanical analysis using a computational model of the female pelvis, developed from a female subjects high-resolution magnetic resonance (MR) images. The urethral hypermobility is simulated by weakening the levator ani muscle in the pelvic model. Four positions along the posterior urethra (proximal, midproximal, middle, and mid-distal) were considered for sling implantation. The α-angle, urethral excursion angle, and sling-urethra interaction force generated during Valsalva maneuver were quantitatively characterized to evaluate the effect of the sling implantation position on treatment outcomes and potential complications. Results show concern for overcorrection with a sling implanted at the bladder neck, based on a relatively larger sling-urethra interaction force of 1.77u2009N at the proximal implantation position (compared with 0.25u2009N at mid-distal implantation position). A sling implanted at the mid-distal urethral location provided sufficient correction (urethral excursion angle of 23.8u2009deg after mid-distal sling implantation versus 24.4u2009deg in the intact case) with minimal risk of overtightening and represents the optimal choice for sling surgery. This study represents the first effort utilizing a comprehensive pelvic model to investigate the performance of an implanted sling to correct urethral hypermobility. The computational modeling approach presented in the study can also be used to advance presurgery planning, sling product design, and to enhance our understanding of various surgical risk factors which are difficult to obtain in clinical practice.

Functional mapping of the pelvic floor and sphincter muscles from high-density surface EMG recordings

Introduction and hypothesisKnowledge of the innervation of pelvic floor and sphincter muscles is of great importance to understanding the pathophysiology of female pelvic floor dysfunctions. This report presents our high-density intravaginal and intrarectal electromyography (EMG) probes and a comprehensive innervation zone (IZ) imaging technique based on high-density EMG readings to characterize the IZ distribution.MethodsBoth intravaginal and intrarectal probes are covered with a high-density surface electromyography electrode grid (8u2009×u20098). Surface EMG signals were acquired in ten healthy women performing maximum voluntary contractions of their pelvic floor. EMG decomposition was performed to separate motor-unit action potentials (MUAPs) and then localize their IZs.ResultsHigh-density surface EMG signals were successfully acquired over the vaginal and rectal surfaces. The propagation patterns of muscle activity were clearly visualized for multiple muscle groups of the pelvic floor and anal sphincter. During each contraction, up to 218 and 456 repetitions of motor units were detected by the vaginal and rectal probes, respectively. MUAPs were separated with their IZs identified at various orientations and depths.ConclusionsThe proposed probes are capable of providing a comprehensive mapping of IZs of the pelvic floor and sphincter muscles. They can be employed as diagnostic and preventative tools in clinical practices.

The Fate of Transitional Urology Patients Referred to a Tertiary Transitional Care Center

OBJECTIVEnTo determine the changes in management of children with neurogenic bladder (NGB) or genitourinary congenital anomalies as they moved to our transitional care clinic at the Center for Restorative Pelvic Medicine, a multidisciplinary center led by an adult urologic team dedicated to the long-term care of these patients.nnnMATERIALS AND METHODSnWe retrospectively reviewed charts of patients with NGB or genitourinary congenital abnormalities referred between 2010 and 2013. Analysis included patient characteristics, causes of NGB, bladder management, recurrent urinary tract infection, stones, renal function, upper tract studies, video urodynamics, and change in management.nnnRESULTSnTwenty-four patients with an average age of 22.0 ± 2.7 years were included in analysis. Management was altered in 70.8% of patients (n = 17). Surgical management was instituted in 58.3% (n = 14 of 24) of patients and included bladder augmentation or urinary diversion (n = 7), intravesical botulinum toxin A injections (n = 5), cystolitholapaxy, or cystolithotomy (n = 2). Conservative management was changed in 12.5% (n = 3) of patients and included initiating anticholinergic medication (n = 2) or self-catheterization (n = 1). Follow-up was 8.9 ± 12.1 months.nnnCONCLUSIONnThere is an immense need for transitional care of patients with NGB or genitourinary congenital abnormalities as they grow into adulthood. Nearly 71% of our patients had a change in their bladder management with 38% undergoing a major surgery. This study emphasizes the necessity for a dedicated adult urologic team in conjunction with a comprehensive team to care for these complex patients because their urologic care and needs may vary significantly from their childhood.

Functional Magnetic Resonance Imaging with Concurrent Urodynamic Testing Identifies Brain Structures Involved in Micturition Cycle in Patients with Multiple Sclerosis

Purpose: Neurogenic lower urinary tract dysfunction, which is common in patients with multiple sclerosis, has a significant impact on quality of life. In this study we sought to determine brain activity processes during the micturition cycle in female patients with multiple sclerosis and neurogenic lower urinary tract dysfunction. Materials and Methods: We report brain activity on functional magnetic resonance imaging and simultaneous urodynamic testing in 23 ambulatory female patients with multiple sclerosis. Individual functional magnetic resonance imaging activation maps at strong desire to void and at initiation of voiding were calculated and averaged at Montreal Neuroimaging Institute. Areas of significant activation were identified in these average maps. Subgroup analysis was performed in patients with elicitable neurogenic detrusor overactivity or detrusor‐sphincter dyssynergia. Results: Group analysis of all patients at strong desire to void yielded areas of activation in regions associated with executive function (frontal gyrus), emotional regulation (cingulate gyrus) and motor control (putamen, cerebellum and precuneus). Comparison of the average change in activation between previously reported healthy controls and patients with multiple sclerosis showed predominantly stronger, more focal activation in the former and lower, more diffused activation in the latter. Patients with multiple sclerosis who had demonstrable neurogenic detrusor overactivity and detrusor‐sphincter dyssynergia showed a trend toward distinct brain activation at full urge and at initiation of voiding respectively. Conclusions: We successfully studied brain activation during the entire micturition cycle in female patients with neurogenic lower urinary tract dysfunction and multiple sclerosis using a concurrent functional magnetic resonance imaging/urodynamic testing platform. Understanding the central neural processes involved in specific parts of micturition in patients with neurogenic lower urinary tract dysfunction may identify areas of interest for future intervention.

Neurogenic Bowel Dysfunction in Patients with Neurogenic Bladder

Patients with primary neurologic conditions often experience urinary and bowel dysfunction due to loss of sensory and/or motor control. Neurogenic bowel dysfunction is frequently characterized by both constipation and fecal incontinence. In general, the management of neurogenic bowel dysfunction has been less well studied than bladder dysfunction despite their close association. It is widely accepted that establishment of a multifaceted bowel regimen is the cornerstone of conservative management. Continuing assessment is necessary to determine the need for more invasive interventions. In the clinical setting, the Urologist may be the principle provider addressing bowel concerns in addition to bladder dysfunction, and furthermore, treatment of one often impacts the other. Future directions should include development of follow-up and management guidelines that address the comprehensive care of this patient population.