Noninvasive, Individualized Cortical Modulation Using Transcranial Rotating Permanent Magnet Stimulator for Voiding Dysfunction in Women with Multiple Sclerosis: A Pilot Trial.

PURPOSE: Voiding dysfunction (VD) leading to urinary retention is a common neurogenic lower urinary tract symptom in patients with multiple sclerosis (MS). Currently, the only effective management for patients with MS with VD is catheterization. Transcranial Rotating Permanent Magnet Stimulator (TRPMS) is a noninvasive, portable, multifocal neuromodulator that simultaneously modulates multiple cortical regions and the strength of their functional connections. In this pilot trial (ClinicalTrials.gov Identifier: NCT03574610), we investigated the safety and therapeutic effects of TRPMS in modulating brain regions of interest (ROIs) engaged with voiding initiation to improve VD in MS women. MATERIALS AND METHODS: Ten MS women with VD (having % post-void residual/bladder capacity [%PVR/BC] ≥40% or being in the lower 10th percentile of the Liverpool nomogram) underwent concurrent functional magnetic resonance imaging/urodynamic study (fMRI/UDS) with 3 cycles of bladder filling/emptying, at baseline and post-treatment. Predetermined ROIs and their activations at voiding initiation were identified on patients' baseline fMRI/UDS scans, corresponding to microstimulator placement. Patients received 10 consecutive 40-minute treatment sessions. Brain activation group analysis, noninstrumented uroflow, and validated questionnaires were compared at baseline and post-treatment. RESULTS: No treatment-related adverse effects were reported. Post-treatment, patients showed significantly increased activation in regions known to be involved at voiding initiation in healthy subjects. %PVR/BC significantly decreased. Significant improvement of bladder emptying symptoms were reported by patients via validated questionnaires. CONCLUSIONS: Both neuroimaging and clinical data suggested TRPMS effectively and safely modulated brain regions that are involved in the voiding phase of the micturition cycle, leading to clinical improvements in bladder emptying in patients with MS.

Altered bladder-related brain network in multiple sclerosis women with voiding dysfunction.

OBJECTIVES: A number of neurourology imaging studies have mainly focused on investigating the brain activations during micturition in healthy and neuropathic patients. It is, however, also necessary to study brain functional connectivity (FC) within bladder-related regions to understand the brain organization during the execution of bladder function. This study aims to identify the altered brain network associated with bladder function in multiple sclerosis (MS) women with voiding dysfunction through comparisons with healthy subjects via concurrent urodynamic study (UDS)/functional magnetic resonance imaging (fMRI). MATERIALS AND METHODS: Ten healthy adult women and nine adult ambulatory women with clinically stable MS for ≥6 months and symptomatic voiding phase neurogenic lower urinary tract dysfunction (NLUTD) underwent UDS/fMRI evaluation with a task of bladder filling/emptying that was repeated three to five times. We quantitatively compared their FC within 17 bladder-related brain regions during two UDS phases: "strong desire to void" and "(attempt at) voiding initiation." RESULTS: At "strong desire to void," the healthy group showed significantly stronger FC in regions involved in bladder filling and suppression of voiding compared to the patient group. These regions included the bilateral anterior cingulate cortex, right supplementary motor area, and right middle frontal gyrus. During "(attempt at) voiding initiation," healthy subjects exhibited stronger FC in the right inferior frontal gyrus compared to MS patients. CONCLUSION: Our study offers a new way to identify alterations in the neural mechanisms underlying NLUTD and provides potential targets for clinical interventions (such as cortical neuromodulation) aimed at restoring bladder functions in MS patients.

The AUA/SUFU Guideline on Adult Neurogenic Lower Urinary Tract Dysfunction: Treatment and Follow-up.

PURPOSE: The clinician treating patients with neurogenic lower urinary tract dysfunction (NLUTD) needs to balance a variety of factors when making treatment decisions. In addition to the patient's urologic symptoms and urodynamic findings, other issues that may influence management options of the lower urinary tract include cognition, hand function, type of neurologic disease, mobility, bowel function/management, and social and caregiver support. This Guideline allows the clinician to understand the options available to treat patients, understand the findings that can be seen in NLUTD, and appreciate which options are best for each individual patient. This allows for decisions to be made with the patient, in a shared decision-making manner, such that the patient's quality of life can be optimized with respect to their bladder management. MATERIALS AND METHODS: A comprehensive search for studies assessing patients undergoing evaluation, surveillance, management, or follow-up for NLUTD was conducted from January 2001 through October 2017 and was rerun in February 2021 to capture newer literature. The primary search returned 20,496 unique citations. Following a title and abstract screen, full texts were obtained for 3,036 studies. During full-text review, studies were primarily excluded for not meeting the PICO criteria. One hundred eight-four primary literature studies met the inclusion criteria and were included in the evidence base. RESULTS: This guideline was developed to inform clinicians on the proper evaluation, diagnosis, and risk stratification of adult patients with NLUTD and the non-surgical and surgical treatment options available. Additional statements on urinary tract infection and autonomic dysreflexia were developed to guide the clinician. CONCLUSIONS: NLUTD patients may undergo non-surgical and surgical treatment options depending on their level of risk, symptoms, and urodynamic findings. Appropriate follow-up, primarily based on their risk stratification, must be maintained after treatment.

The AUA/SUFU Guideline on Adult Neurogenic Lower Urinary Tract Dysfunction: Diagnosis and Evaluation.

PURPOSE: The clinician treating patients with neurogenic lower urinary tract dysfunction (NLUTD) needs to balance a variety of factors when making treatment decisions. In addition to the patient's urologic symptoms and urodynamic findings, other issues that may influence management options of the lower urinary tract include cognition, hand function, type of neurologic disease, mobility, bowel function/management, and social and caregiver support. This Guideline allows the clinician to understand the options available to treat patients, understand the findings that can be seen in NLUTD, and appreciate which options are best for each individual patient. This allows for decisions to be made with the patient, in a shared decision-making manner, such that the patient's quality of life can be optimized with respect to their bladder management. MATERIALS AND METHODS: A comprehensive search for studies assessing patients undergoing evaluation, surveillance, management, or follow-up for NLUTD was conducted from January 2001 through October 2017 and was rerun in February 2021 to capture newer literature. The primary search returned 20,496 unique citations. Following a title and abstract screen, full texts were obtained for 3,036 studies. During full-text review, studies were primarily excluded for not meeting the PICO criteria. One hundred eight-four primary literature studies met the inclusion criteria and were included in the evidence base. RESULTS: This guideline was developed to inform clinicians on the proper evaluation, diagnosis, and risk stratification of patients with NLUTD and the non-surgical and surgical treatment options available. Additional statements on urinary tract infection and autonomic dysreflexia were developed to guide the clinician. This Guideline is for adult patients with NLUTD and pediatric NLUTD will not be discussed. CONCLUSIONS: NLUTD patients should be risk-stratified as either low-, moderate-, high-, or unknown-risk. After diagnosis and stratification, patients should be monitored according to their level of risk at regular intervals. Patients who experience new or worsening signs and symptoms should be reevaluated and risk stratification should be repeated.

High spatial correlation in brain connectivity between micturition and resting states within bladder-related networks using 7 T MRI in multiple sclerosis women with voiding dysfunction.

BACKGROUND: Several studies have reported brain activations and functional connectivity (FC) during micturition using functional magnetic resonance imaging (fMRI) and concurrent urodynamics (UDS) testing. However, due to the invasive nature of UDS procedure, non-invasive resting-state fMRI is being explored as a potential alternative. The purpose of this study is to evaluate the feasibility of utilizing resting states as a non-invasive alternative for investigating the bladder-related networks in the brain. METHODS: We quantitatively compared FC in brain regions belonging to the bladder-related network during the following states: 'strong desire to void', 'voiding initiation (or attempt at voiding initiation)', and 'voiding (or continued attempt of voiding)' with FC during rest in nine multiple sclerosis women with voiding dysfunction using fMRI data acquired at 7 T and 3 T. RESULTS: The inter-subject correlation analysis showed that voiding (or continued attempt of voiding) is achieved through similar network connections in all subjects. The task-based bladder-related network closely resembles the resting-state intrinsic network only during voiding (or continued attempt of voiding) process but not at other states. CONCLUSION: Resting states fMRI can be potentially utilized to accurately reflect the voiding (or continued attempt of voiding) network. Concurrent UDS testing is still necessary for studying the effects of strong desire to void and initiation of voiding (or attempt at initiation of voiding).

Dissecting the role of radical cystectomy and urinary diversion in post-operative complications: an analysis using the American College of Surgeons national surgical quality improvement program database.

OBJECTIVE: To characterize the contribution of the extirpative and reconstructive portions of radical cystectomy (RC) to complications rates, and assess differences between urinary diversion (UD) types. MATERIALS AND METHODS: We conducted a retrospective cohort study comparing patients undergoing UD alone or RC+UD for bladder cancer from 2006 to 2017 using ACS National Surgical Quality Improvement Program database. The primary outcome was major complications, while secondary outcomes included minor complications and prolonged length of stay. Propensity score matching (PSM) was utilized to assess the association between surgical procedure (UD alone or RC+UD) and outcomes, stratified by diversion type. Lastly, we examined differences in complication rates between ileal conduit (IC) vs. continent UD (CUD). RESULTS: When comparing RC + IC and IC alone, PSM yielded 424 pairs. IC alone had a lower risk of any complication (HR 0.63, 95% CI 0.52-0.75), venous thromboembolism (HR 0.45, 95% CI 0.22-0.91) and bleeding needing transfusion (HR 0.41, 95% CI 0.32-0.52). This trend was also noted when comparing RC + CUD to CUD alone. CUD had higher risk of complications than IC, both with (56.6% vs 52.3%, p = 0.031) and without RC (47.8% vs 35.1%, p=0.062), and a higher risk of infectious complications, both with (30.5% vs 22.7%, p< 0.001) and without RC (34.0% vs 22.0%, p=0.032). CONCLUSIONS: RC+UD, as compared to UD alone, is associated with an increased risk of major complications, including bleeding needing transfusion and venous thromboembolism. Additionally, CUD had a higher risk of post-operative complication than IC.

Brain activation patterns of female multiple sclerosis patients with voiding dysfunction.

AIMS: We compared brain activation patterns between female multiple sclerosis (MS) patients with voiding dysfunction (VD) and those without. We aim to expand current knowledge of supraspinal correlates of voiding initiation within a cohort of female MS patients with and without VD. MATERIALS AND METHODS: Twenty-eight ambulatory female MS patients with stable disease and lower urinary tract dysfunction were recruited for this study. Subjects were divided into group 1, without VD (n = 14), and group 2, with VD (n = 14), defined as postvoid residual urine of ≥40% of maximum cystometric capacity or need for self-catheterization. We recorded brain activity via functional magnetic resonance imaging (fMRI) with simultaneous urodynamic testing. Average fMRI activation maps (the Student t test) were created for both groups, and areas of significant activation were identified (P < .05). A priori regions of interest (ROIs), identified by prior meta-analysis to be involved in voiding, were selected. RESULTS: Group-averaged blood-oxygen level-dependent (BOLD) activation maps demonstrated significant differences between groups 1 and 2 during initiation of voiding with group 2 showing significantly lower levels of activation in all ROIs except for the left cerebellum and right cingulate gyrus. Interestingly, group 2 displayed negative BOLD signals, while group 1 displayed positive signals in the right and left pontine micturition center, right periaqueductal gray, left thalamus, and left cingulate gyrus. The activation map of group 1 was similar to healthy controls. CONCLUSIONS: Our results support the hypothesis that distinct supraspinal activation patterns exist between female MS patients with VD and those without.

Higher Neural Correlates in Patients with Multiple Sclerosis and Neurogenic Overactive Bladder Following Treatment with Intradetrusor Injection of OnabotulinumtoxinA.

PURPOSE: OnabotulinumtoxinA is a well described treatment of neurogenic overactive bladder. While motor effects on the detrusor muscle have been extensively studied, the sensory effects have not. The aim of this study was to evaluate the impact of intradetrusor onabotulinumtoxinA injection on brain activity in female patients with multiple sclerosis and neurogenic overactive bladder. MATERIALS AND METHODS: We prospectively studied 12 women with stable multiple sclerosis and neurogenic overactive bladder using concurrent functional magnetic resonance imaging and urodynamic studies prior to and 6 to 10 weeks following onabotulinumtoxinA injection. Individual functional magnetic resonance imaging activation maps at the time of strong urgency were averaged before and after onabotulinumtoxinA injection where areas of significant activation were identified. RESULTS: After onabotulinumtoxinA injection functional magnetic resonance imaging activation increased in the right cingulate body (p = 0.0012), the left posterior cingulate (p = 0.02), the left anterior cingulate (p = 0.0015), the right prefrontal cortex (p = 0.0015), the insula (p = 0.0138) and the pons micturition center (p = 0.05). Sparse areas showed decreased activity, including the left cerebellum (p = 0.001), the left fusiform gyrus (p = 0.065) and the bilateral lentiform nucleus (p = 0.026). CONCLUSIONS: Intradetrusor injection of onabotulinumtoxinA appeared to increase the activity of most brain regions known to be involved in the sensation and process of urinary urgency in female patients with multiple sclerosis and neurogenic overactive bladder. To our knowledge this is the first study of its kind to evaluate the possible effects of onabotulinumtoxinA at the human brain level where sensory awareness is located. This activation pattern may be used to further phenotype patients to optimize therapy or determine the sensory effects of onabotulinumtoxinA beyond the bladder.

Modulatory effects of intravesical P2X2/3 purinergic receptor inhibition on lower urinary tract electromyographic properties and voiding function of female rats with moderate or severe spinal cord injury.

OBJECTIVES: To evaluate the role that intravesical P2X2/3 purinergic receptors (P2X2/3Rs) play in early and advanced neurogenic lower urinary tract (LUT) dysfunction after contusion spinal cord injury (SCI) in female rats. MATERIALS AND METHODS: Female Sprague-Dawley rats received a thoracic Th8/Th9 spinal cord contusion with either force of 100 kDy (cN); moderate) or 150 kDy (cN; severe); Sham rats had no injury. Evaluations on urethane-anesthetised rats were conducted at either 2 or 4 weeks after SCI. LUT electrical signals and changes in bladder pressure were simultaneously recorded using cystometry and a set of custom-made flexible microelectrodes, before and after intravesical application of the P2X2/3R antagonist AF-353 (10 µM), to determine the contribution of P2X2/3R-mediated LUT modulation. RESULTS: Severe SCI significantly increased bladder contraction frequency, and reduced both bladder pressure amplitude and intraluminal-pressure high-frequency oscillations (IPHFO). Intravesical P2X2/3R inhibition did not modify bladder pressure or IPHFO in the Sham and moderate-SCI rats, although did increase the intercontractile interval (ICI). At 2 weeks after SCI, the Sham and moderate-SCI rats had significant LUT electromyographic activity during voiding, with a noticeable reduction in LUT electrical signals seen at 4 weeks after SCI. Intravesical inhibition of P2X2/3R increased the ICI in the Sham and moderate-SCI rats at both time-points, but had no effect on rats with severe SCI. The external urethral sphincter (EUS) showed strong and P2X2/3R-independent electrical signals in the Sham and moderate-SCI rats in the early SCI stage. At 4 weeks after SCI, the responsiveness of the EUS was significantly attenuated, independently of SCI intensity. CONCLUSIONS: This study shows that electrophysiological properties of the LUT are progressively impaired depending on SCI intensity and that intravesical P2X2/3R inhibition can attenuate electrical activity in the neurogenic LUT at early, but not at semi-chronic SCI. This translational study should be useful for planning clinical evaluations.

Similarity of functional connectivity patterns in patients with multiple sclerosis who void spontaneously versus patients with voiding dysfunction.

AIM: To investigate if Multiple Sclerosis (MS) lesion characteristics affect functional brain connectivity (FC) during bladder voiding. METHODS: Twenty-seven ambulatory female patients with MS completed our functional magnetic resonance imaging (fMRI)/urodynamic testing (UDS) platform. Individual fMRI activation maps were generated at initiation of voiding. FC patterns of these regions were calculated and compared. Similarity of the FC pattern from one patient relative to all others was expressed by a parameter FC_sim. A statistical analysis was performed to reveal the relationship of the existence of an enhancing brain lesion, the size of the largest lesion and the ability to void spontaneously to this FC similarity measure. RESULTS: FC_sim values were significantly lower for patients with an enhancing MS lesion (11.7 ± 3.1 vs 5.3 ± 2.1 P < 0.001). Lesion size smaller than 20 mm inversely correlated significantly with FC_sim (R = -0.43, P = 0.05). Patients with the ability to void spontaneously had a higher FC_sim value (12.0 ± 2.8 vs 9.3 ± 4.4 s, P = 0.08). Patients that exhibited a decrease of compliance also showed a significantly lower FC_sim value (11.3 ± 3.5 vs 4.7 ± 0.7, P < 1e-5). CONCLUSION: FC connectivity analysis derived from an fMRI task-based study including repetitive voiding cycles is able to quantify the heterogeneity of connectivity patterns in the brain of MS patients. FC similarity decreased with maximum lesion size or the presence of enhancing lesions affecting the ability to void spontaneously.

Non-invasive electromyographic estimation of motor unit number in the external anal sphincter of the rat.

AIMS: The external anal sphincter (EAS) is essential for maintaining fecal continence. Neurological disorders or traumatic injuries to muscle and nervous systems could lead to EAS denervation. Currently, there are no techniques available to document global innervation changes in the EAS in vivo. The aim of this study was to develop a novel approach to non-invasively estimate the number of functioning motor units (MUs) in the EAS and validate with immunofluorescent techniques in rats. METHODS: Intra-rectal surface electromyography (EMG) signals of the EAS, induced by a series of intra-vaginally delivered pudendal nerve stimulations with different intensities, were recorded. Variation in EMG responses at different intensities was used to estimate the value of a single motor unit potential (SMUP) in order to perform the proposed EAS motor unit number estimation (MUNE) approach. The EAS MUNE was tested in 12 female Sprague-Dawley rats, and validated by comparing against the EAS myofiber counting results achieved by performing immunostaining of acetylcholine receptors in 7 of the 12 rats. RESULTS: The mean MU number was 35 ± 9, with an averaged SMUP size of 52.49 ± 20.39 µV. The mean number of successfully identified myofibers was 652.7 ± 130.6 myofiber/EAS. Significance of linear regression between the immunofluorescent results and the MUNE was confirmed (P < 0.01). CONCLUSIONS: Our study represents the first effort to non-invasively assess the innervation of the EAS in vivo using the rat as a pre-clinical model. This approach can potentially enable future clinical applications for advanced diagnosis and treatment of neurogenic EAS disorders.

Modern Theories of Pelvic Floor Support : A Topical Review of Modern Studies on Structural and Functional Pelvic Floor Support from Medical Imaging, Computational Modeling, and Electromyographic Perspectives.

PURPOSE OF REVIEW: Weakened pelvic floor support is believed to be the main cause of various pelvic floor disorders. Modern theories of pelvic floor support stress on the structural and functional integrity of multiple structures and their interplay to maintain normal pelvic floor functions. Connective tissues provide passive pelvic floor support while pelvic floor muscles provide active support through voluntary contraction. Advanced modern medical technologies allow us to comprehensively and thoroughly evaluate the interaction of supporting structures and assess both active and passive support functions. The pathophysiology of various pelvic floor disorders associated with pelvic floor weakness is now under scrutiny from the combination of (1) morphological, (2) dynamic (through computational modeling), and (3) neurophysiological perspectives. This topical review aims to update newly emerged studies assessing pelvic floor support function among these three categories. RECENT FINDINGS: A literature search was performed with emphasis on (1) medical imaging studies that assess pelvic floor muscle architecture, (2) subject-specific computational modeling studies that address new topics such as modeling muscle contractions, and (3) pelvic floor neurophysiology studies that report novel devices or findings such as high-density surface electromyography techniques. We found that recent computational modeling studies are featured with more realistic soft tissue constitutive models (e.g., active muscle contraction) as well as an increasing interest in simulating surgical interventions (e.g., artificial sphincter). Diffusion tensor imaging provides a useful non-invasive tool to characterize pelvic floor muscles at the microstructural level, which can be potentially used to improve the accuracy of the simulation of muscle contraction. Studies using high-density surface electromyography anal and vaginal probes on large patient cohorts have been recently reported. Influences of vaginal delivery on the distribution of innervation zones of pelvic floor muscles are clarified, providing useful guidance for a better protection of women during delivery. We are now in a period of transition to advanced diagnostic and predictive pelvic floor medicine. Our findings highlight the application of diffusion tensor imaging, computational models with consideration of active pelvic floor muscle contraction, high-density surface electromyography, and their potential integration, as tools to push the boundary of our knowledge in pelvic floor support and better shape current clinical practice.

Workflow for Visualization of Neuroimaging Data with an Augmented Reality Device.

Commercial availability of three-dimensional (3D) augmented reality (AR) devices has increased interest in using this novel technology for visualizing neuroimaging data. Here, a technical workflow and algorithm for importing 3D surface-based segmentations derived from magnetic resonance imaging data into a head-mounted AR device is presented and illustrated on selected examples: the pial cortical surface of the human brain, fMRI BOLD maps, reconstructed white matter tracts, and a brain network of functional connectivity.

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.

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

INTRODUCTION AND HYPOTHESIS: Knowledge 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. METHODS: Both intravaginal and intrarectal probes are covered with a high-density surface electromyography electrode grid (8 × 8). 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. RESULTS: High-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. CONCLUSIONS: The 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.

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

INTRODUCTION AND HYPOTHESIS: This study aimed to assess the role of individual anatomical structures and their combinations to urethral support function. METHODS: A 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 pressure = 100 cmH2O). Seven individual support structures and five of their combinations were studied. RESULT: Among 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. CONCLUSIONS: The 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.

Pelvic Organ Prolapse in Female Patients Presenting to Transitional Urology Care Clinic.

PURPOSE: Patients with congenital genitourinary abnormalities are growing into adulthood and their expectations, especially in the areas of sexual function and fertility are creating unforeseen challenges for health care providers. We review the incidence and management of pelvic organ prolapse at our Transitional Urology Clinic. MATERIALS AND METHODS: This study is a retrospective chart review of the presentation and treatment of patients with clinically bothersome pelvic organ prolapse seen at our tertiary Transitional Urology Clinic during 2012 to 2015. RESULTS: Seven patients with a mean age of 22.8 years presented to our clinic with clinically bothersome prolapse. Four patients had myelomeningocele, 2 had sacral agenesis and 1 had bladder exstrophy. All were on self-catheterization. Three patients were sexually active and 1 had an intact uterus and desired fertility. Bothersome symptoms included vaginal bulge in 6 cases, difficult vaginal intercourse in 1 and difficult catheterization in 1. For the leading edge of Bp (anterior compartment) prolapse the median POP-Q (Pelvic Organ Prolapse Quantification System) stage was 3 (range 1 to 3), for Bp (posterior compartment) prolapse it was 1 (range 0 to 3) and for C (vaginal vault or cervical) prolapse it was 2 (range 1 to 3). Management included pessary in 1 case, hysterectomy with bilateral uterosacral ligament suspension in 4, sacrocolpopexy in 1 and observation in 1. Mean followup was 17.6 months (range 1 to 92). One of the 5 patients treated with surgical intervention had recurrence in the anterior compartment and vaginal vault. CONCLUSIONS: Females with congenital genitourinary anomalies present with pelvic organ prolapse at a much younger age and a more advanced stage. There is a paucity of literature on the epidemiology, presentation and management of pelvic organ prolapse in this patient population.

Inhibition of urothelial P2X3 receptors prevents desensitization of purinergic detrusor contractions in the rat bladder.

OBJECTIVES: To evaluate whether P2X3 receptors (P2X3R) are expressed in the bladder urothelium and to determine their possible function in modulating purinergic detrusor contractions in the rat urinary bladder. MATERIALS AND METHODS: The expression of urothelial receptors was determined using conventional immunohistochemistry in bladders from normal Sprague-Dawley rats. The urothelial layer was removed by incubation with protamine, and disruption of the urothelium was confirmed using haematoxylin and eosin staining on bladder sections. Open cystometry was used to determine the effects of both urothelial removal as well as intravesical application of a specific P2X3R antagonist on bladder properties from intact and protamine-treated rats. Isometric contractile responses to potassium chloride (KCl) depolarization, electrical field stimulation (EFS) or chemical P2X activation were determined in normal and urothelium-denuded bladder strips, with and without application of the P2X3R antagonist. RESULTS: Immunohistochemical staining showed high expression of P2X3R in the medial and basal layers of the urothelium. Removal of the urothelial layer disturbed normal bladder performance in vivo and eliminated the effects of the P2X3R antagonist on increasing the contractile interval and reducing the amplitude of voiding contractions. Removal of the urothelium did not affect bladder strip contractile responses to KCl depolarization or EFS. Pharmacological inhibition of P2X3R prevented desensitization to P2X-mediated detrusor muscle contractions during EFS only in the strips with an intact urothelium. A concentration-dependent, specific inhibition of P2X3R also prevented desensitization of purinergic contractile responses in intact bladder strips. CONCLUSIONS: In the rat bladder, medial and basal urothelial cells express P2X3R, and specific inhibition of the receptor leads to a more hyporeflexive bladder condition. This pathway may involve P2X3R driving a paracrine amplification of ATP released from umbrella cells to increase afferent transmission in the sub-urothelial sensory plexus and desensitization of P2X1-mediated purinergic detrusor contractions.