Classification of multiple sclerosis women with voiding dysfunction using machine learning: Is functional connectivity or structural connectivity a better predictor?

Introduction: Machine learning (ML) is an established technique that uses sets of training data to develop algorithms and perform data classification without using human intervention/supervision. This study aims to determine how functional and anatomical brain connectivity (FC and SC) data can be used to classify voiding dysfunction (VD) in female MS patients using ML. Methods: Twenty-seven ambulatory MS individuals with lower urinary tract dysfunction were recruited and divided into two groups (Group 1: voiders [V, n = 14]; Group 2: VD [n = 13]). All patients underwent concurrent functional MRI/urodynamics testing. Results: Best-performing ML algorithms, with highest area under the curve (AUC), were partial least squares (PLS, AUC = 0.86) using FC alone and random forest (RF) when using SC alone (AUC = 0.93) and combined (AUC = 0.96) as inputs. Our results show 10 predictors with the highest AUC values were associated with FC, indicating that although white matter was affected, new connections may have formed to preserve voiding initiation. Conclusions: MS patients with and without VD exhibit distinct brain connectivity patterns when performing a voiding task. Our results demonstrate FC (grey matter) is of higher importance than SC (white matter) for this classification. Knowledge of these centres may help us further phenotype patients to appropriate centrally focused treatments in the future.

Preliminary Analysis of Brain Footprints in Multiple Sclerosis Females With Detrusor Sphincter Dyssynergia: A Concurrent Urodynamic and Functional Magnetic Resonance Imaging Study.

PURPOSE: This study evaluates the grey and white brain matter characteristics in women with multiple sclerosis (MS) and detrusor sphincter dyssynergia (DSD). Grey matter is assessed via the functional connectivity (FC) of brain regions activated during voiding, using functional magnetic resonance imaging (fMRI). Two white matter tracts involved in bladder function, the anterior thalamic radiation (ATR) and superior longitudinal fasciculus (SLF), were evaluated using diffusion tensor imaging. METHODS: Twenty-seven women with MS (2 groups: no-DSD [n=23] or DSD [n=4]), and 8 healthy controls (HCs) underwent concurrent urodynamic-fMRI evaluation with 4 cycles of bladder filling and emptying. A FC similarity measure (FC_sim) was calculated for each subject to express the similarity of individual FC at voiding initiation compared to all FC patterns. ATR and SLF tracts were traced and their fractional anisotropy (FA) and mean diffusivity (MD) were recorded. RESULTS: Mean FC_sim values were significantly different among the 3 groups indicating distinct FC patterns; however, no significant difference was found between DSD and no-DSD groups. DSD group showed trends of lower FA and higher MD- indicating loss of coherence-in all tracts compared to HCs, and in the left and right ATR when compared to MS women with neither DSD nor voiding dysfunction (VD), suggesting more damage in these tracts for MS women with DSD. CONCLUSION: Women with MS show distinctly different FC patterns compared to HCs. There are trends showing more damage in the ATR in women with MS and DSD compared to those with neither DSD nor VD.

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.

Low Interrater Reliability of Videourodynamic Diagnosis of Detrusor External Sphincter Dyssynergia.

OBJECTIVES: Complex bladder dysfunction requires urodynamic testing, often under fluoroscopy termed videourodynamic study (VUDS), to assist the diagnosis and management. Videourodynamic study is an objective tool with high interrater reliability (IRR) for identifying detrusor overactivity. However, IRR has not been validated with disorders associated with neurogenic bladder (NGB). We aim to investigate the IRR of VUDS to diagnose detrusor external sphincter dyssynergia (DESD) among NGB patients and hypothesize a high IRR to DESD diagnosis on VUDS. METHODS: Videourodynamics tracings with fluoroscopic images were rated either positive or negative for evidence of DESD by 4 raters (2 neurourologists, neurourology fellow, and urology postgraduate year 2 resident), in patients who underwent VUDS from 2013 to 2017. The study population had known NGB without previous bladder reconstruction. The IRR was determined using percent agreement and κ values. RESULTS: The experts had a percent agreement of 82.1% (κ = 0.26). Expert 1 and expert 2 had a percent agreement of 63.6% (κ = 0.1497) and 68.9% (κ = 0.2967), respectively, when compared with the fellow. Sensitivity and specificity ranged from 28% to 75% and 64% to 93%, respectively. The negative predictive values ranged from 90% to 95%. CONCLUSIONS: The IRR to diagnose DESD on VUDS was much lower than expected, even among experts, and was likely multifactorial and partially owing to lack of clinical context and lack of standardized VUDS interpretation of the electromyogram. A high negative predictive value was found among all participants. Further research is needed to evaluate factors contributing to the low reproducibility of DESD diagnosis on VUDS.

Are White Matter Tract Integrities Different in Multiple Sclerosis Women With Voiding Dysfunction?

OBJECTIVES: Two white matter tracts (WMTs) are proposed to be involved in bladder function: anterior thalamic radiation and superior longitudinal fasciculus. Multiple sclerosis (MS) patients with voiding dysfunction (VD) may have distinct changes in these 2 WMTs. This study aims to compare the fractional anisotropy (FA) and mean diffusivity (MD) from diffusion tensor imaging of MS females with and without VD versus healthy controls (HCs). METHODS: Prospective observational cohorts of 28 female MS patients and 11 HCs were recruited. Multiple sclerosis patients were divided into 2 groups: voiders (patients without VD, n = 14) and VD (patients with VD, n = 14). Diffusion tensor imaging of each subject was obtained, from which FA and MD maps were generated. The mean FA and MD of each WMT on both sides were analyzed using one-way analysis of variance and pairwise comparison with adjusted P values. RESULTS: Overall MS patients had significantly lower mean FA (loss of coherence) and significantly higher mean MD (increased free diffusion) than HCs in both WMTs, indicating more damage. Furthermore, VD showed a trend of loss of integrity in both WMTs when compared with voiders with lower FA and higher MD. CONCLUSIONS: There is damage reflected by lower FA and higher MD values in the proposed WMTs involved in bladder function in MS women. Voiding dysfunction in this patient population can be attributed to these damages considering women with VD demonstrated a trend of deterioration in these WMTs compared with women without VD. Future studies with larger sample sizes should be done to further confirm this correlation.

Voiding Dysfunction in Old Male Rats Associated With Enlarged Prostate and Irregular Afferent-Triggered Reflex Responses.

PURPOSE: This study was conducted to evaluate the hypothesis that an enlarged prostate in old rats may lead to complications associated with voiding dysfunction involving ionotropic P2X2/3-type purinergic receptors. METHODS: Intact animals were divided into male young (MYR; 8-10 weeks old) and male old (MOR; 20 months old) rats. The animals underwent simultaneous detrusor electromyography (EMG) and suprapubic cystometry (CMG) under urethane anesthesia. Immunofluorescence techniques were used to evaluate prostatic autonomic innervation and P2X3R expression in bladder urothelial cells. The functional role of P2X3R was characterized by intramuscular application of AF-353, a selective P2X2/3R antagonist. RESULTS: The prostate index significantly increased in MOR, suggestive of an enlarged prostate affecting micturition patterns. Significant EMG and CMG differences were found between MYR and MOR. Higher immunoreactivity for P2X2/3R in the urothelial layer and for prostatic neurofilaments was seen in MOR. Systemic inhibition of P2X2/3R had minimal effects on MYR responsiveness, but improved voiding function in MOR with a marked decrease of intravesical pressure and bladder contractile responses. CONCLUSION: The data support the hypothesis that an enlarged prostate in MOR may contribute to voiding dysfunction involving activation of P2X2/3R, which enhances a prostate-bladder reflex. This reflex may increase bladder afferent transmission and activation of increased prostate innervation, leading to voiding dysfunction.

Functional brain imaging in voiding dysfunction.

PURPOSE OF REVIEW: Voiding dysfunction (VD) is morbid, costly, and leads to urinary tract infections, stones, sepsis, and permanent renal failure. Evaluation and diagnosis of VD in non-obstructed patients can be challenging. Potential diagnostic and therapeutic options beyond the bladder, such as brain centers involved in voiding have been proposed as promising targets. This review focuses on current and future applications of functional neuroimaging in human in voiding and in patients with VD. RECENT FINDINGS: The current understanding of brain centers, and their roles in initiating, maintaining and/or modulating voiding, is rudimentary in humans and in patients with VD. With the advent and advancement in functional neuroimaging we are gaining more insight into specific brain regions involved in the voiding phase of micturition. In healthy individuals, right dorsomedial pontine tegmentum, periaqueductal grey, hypothalamus, and the inferior, medial and superior frontal gyrus have been identified as regions of interest in voiding. SUMMARY: Functional neuroimaging could suggest new diagnostic methods and provides crucial steps towards therapeutic options for the morbid and intractable VD condition, in patients with neurogenic (e.g. MS or Strokes) or non-neurogenic VD (e.g. underactive bladder or Fowler's syndrome).

Outcomes of Intradetrusor OnabotulinumtoxinA Injection in Adults with Congenital Spinal Dysraphism in Tertiary Transitional Urology Clinic.

PURPOSE: Published data regarding intradetrusor injection of onabotulinumtoxinA in adults with congenital spinal dysraphism are scarce. In this study, we retrospectively investigated the outcomes of intradetrusor injection of onabotulinumtoxinA in this setting. MATERIALS AND METHODS: Billing codes were used to identify 149 patients who underwent onabotulinumtoxinA injection between 2012-2016 at our tertiary transitional urology clinic. Charts were then reviewed to identify patients with congenital spinal dysraphism. RESULTS: A total of 18 patients with the mean age of 20.76 (±3.03) years at the time of 1st onabotulinumtoxinA injection were identified. All patients had urinary incontinence. Urinary incontinence improved by injection of 200 or 300 U of onabotulinumtoxinA in 81.2% of patients and 63.6% of them became dry (p= 0.023). Mean glomerular filtration rate before and 13.3 (±9) months after treatment was 100.2 (±17.2) and 120.1 (±16.6) mL/min/1.73 m2 respectively (p= 0.41). Baseline hydronephrosis improved in 3 of 4 patients. Repeat urodynamic study after injection was done in 11 patients who did not clinically improve or who had loss of bladder compliance at baseline (29.3 Vs. 67.2 ml/cmH2O). Mean maximum cystometric capacity before and after injection was 310.1 and 380.2 mL (p= 0.045). Mean bladder compliance before and after treatment was 29.2 and 28.7 ml/cmH2O respectively (p= 0.48) in this high risk group. CONCLUSIONS: Intradetrusor onabotulinumtoxinA injection may improve refractory urinary incontinence in selected adults with spinal dysraphism. However, despite improvement in maximum cystometric capacity, bladder compliance does not improve following therapy in patients who had loss of compliance at baseline.

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.

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.

Surveillance urodynamics for neurogenic lower urinary tract dysfunction: A systematic review.

INTRODUCTION: Baseline urodynamic characterization in patients with neurogenic lower urinary tract dysfunction (NLUTD) allows detection of unsafe storage and voiding pressures and optimization of these parameters through medical or surgical intervention. Surveillance urodynamics (sUDS) studies are performed in the ambulatory setting after baseline characterization, with the goal of monitoring bladder function. How often this study should be performed and the circumstances that should prompt repeated studies are unknown. The primary objective of this review is to evaluate the evidence supporting sUDS in the setting of NLUTD as assessed by whether the study leads to 1) change in patient management; 2) determination of new findings not suggested by imaging or symptoms; and 3) demonstration of superior outcomes compared to observation. The secondary objective is to review sUDS practice patterns among urologists in their assessment of NLUTD. METHODS: PubMed, EMBASE, and Cochrane Library databases were reviewed for English-language literature published between January 1975 and March 2018. RESULTS: Twenty-eight independent articles (1368 patients, 9486 patient-years of followup) were included. Given heterogeneous data, 49% of 263 subjects were asymptomatic, yet demonstrated sUDS abnormality prompting treatment. Eight cross-sectional studies (four spinal cord injury [SCI], two NLUTD, two spina bifida) surveyed urologists regarding current sUDS patterns; 53% of 498 respondents perform sUDS between one and three years. CONCLUSIONS: Evidence supporting optimal surveillance for NLUTD is lacking. Level 2b-4 evidence suggests that sUDS is likely to modify patient treatment and often demonstrates findings that modify treatment in the absence of symptoms or imaging changes.

Synergistic Activities of Abdominal Muscles Are Required for Efficient Micturition in Anesthetized Female Mice.

PURPOSE: To characterize the electromyographic activity of abdominal striated muscles during micturition in urethane-anesthetized female mice, and to quantitatively evaluate the contribution of abdominal responses to efficient voiding. METHODS: Cystometric and multichannel electromyographic recordings were integrated to enable a comprehensive evaluation during micturition in urethane-anesthetized female mice. Four major abdominal muscle domains were evaluated: the external oblique, internal oblique, and superior and inferior rectus abdominis. To further characterize the functionality of the abdominal muscles, pancuronium bromide (25 µg/mL or 50 µg/mL, abdominal surface) was applied as a blocking agent of neuromuscular junctions. RESULTS: We observed a robust activation of the abdominal muscles during voiding, with a consistent onset/offset concomitant with the bladder pressure threshold. Pancuronium was effective, in a dose-dependent fashion, for partial and complete blockage of abdominal activity. Electromyographic discharges during voiding were significantly inhibited by applying pancuronium. Decreased cystometric parameters were recorded, including the peak pressure, pressure threshold, intercontractile interval, and voiding duration, suggesting that the voiding efficiency was significantly compromised by abdominal muscle relaxation. CONCLUSIONS: The relevance of the abdominal striated musculature for micturition has remained a topic of debate in human physiology. Although the study was performed on anesthetized mice, these results support the existence of synergistic abdominal electromyographic activity facilitating voiding in anesthetized mice. Further, our study presents a rodent model that can be used for future investigations into micturition-related abdominal activity.

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.

Protocol for a prospective observational study of cortical lower urinary tract control changes following intradetrusor injection of botulinum toxin-A in patients with multiple sclerosis.

INTRODUCTION: Multiple sclerosis (MS) is a severe debilitating disease that affects patients' quality of life. Up to 90% of patients with MS will develop lower urinary tract dysfunction within the first 18 years of the disease. If oral pharmacotherapy with anticholinergics, behavioural modifications and pelvic floor physical therapy are unsuccessful, intradetrusor injection of botulinum toxin-A (OnaBotA; Botox Allergan, Dublin, Ireland) is a highly effective option for these patients. The local effects of OnaBotA are well understood, but not much is known of its afferent/sensory effects while treating the end organ. Our study will use functional MRI (fMRI) and task-related blood oxygen level-dependent signals to evaluate patients with MS and neurogenic detrusor overactivity (NDO) prior to, and after, intradetrusor injection of OnaBotA with simultaneous urodynamic evaluation. Urinary concentration of brain-derived neurotrophic factor and nerve growth factor will also be collected since it has been shown that patients with an overactive bladder have higher concentrations of these neuropeptides. METHODS AND ANALYSIS: Female patients with MS and lower urinary tract symptoms who previously have undergone urodynamic screening and are refractory to conservative and oral pharmacotherapy management for NDO and are interested in OnaBotA intradetrusor injection will be invited to participate in the study. An fMRI will be performed preintradetrusor injection and postintradetrusor injection of OnaBotA with simultaneous MRI compatible with material urodynamics. Images will be collected and analysed accordingly. ETHICS AND DISSEMINATION: All of the patients are properly consented before enrolling in this study that has been previously approved by the Institutional Review Board. Results of neural connectivity activation will be presented at national and international meetings and published in scholarly journals.

Localized inhibition of P2X7R at the spinal cord injury site improves neurogenic bladder dysfunction by decreasing urothelial P2X3R expression in rats.

AIMS: Reestablishment of bladder function in patients with spinal cord injury (SCI) is a clinical priority. Our objectives were to determine whether SCI-localized inhibition of purinergic P2X7 receptors (P2X7R) improve bladder function by decreasing afferent signals mediated by urothelial P2X3R. MAIN METHODS: Systemic inhibition of P2X7R may improve locomotion in rodent SCI models; however, beneficial effects on bladder function and its physiological mechanisms have not been evaluated. We designed a thermosensitive nanohydrogel (NHG) consisting of the P2X7R antagonist brilliant blue-G (BBG) loaded into silica nanoparticles, embedded with poly(d,l-lactic-co-glycolic) acid, and resuspended in 20% pluronic acid. Female Sprague-Dawley rats with a bilateral dorsal lesion at the thoracic T8/T9 region received either 100µl of an empty NHG, or a NHG containing BBG (BBG-NHG) on top of the spinal tissue. Cystometric properties, spinal immunohistochemistry for P2X7R, and bladder immunohistochemistry for P2X3R were evaluated at four weeks post-SCI. KEY FINDINGS: After SCI animals recovered hind-legs use but neurogenic bladder dysfunction remained. SCI rats treated with BBG-NHG for a period of at least two weeks post-SCI experienced fewer non-voiding contractions. The localized inhibition of P2X7R decreased microglia activation. At the lower urinary tract level we observed, unexpectedly, a concomitant reduction of urothelial P2X3 receptors, which are involved in initiation of bladder afferent transmission to start micturition. SIGNIFICANCE: Localized inhibition of P2X7R for two weeks can be associated with reduced number of microglia and attenuated bladder hyperexcitability mediated by downregulation of urothelial P2X3R in rats with neurogenic bladder dysfunction and independently of locomotor improvements.

Electrical Activity of the Bladder Is Attenuated by Intravesical Inhibition of P2X2/3 Receptors During Micturition in Female Rats.

PURPOSE: To simultaneously monitor electrical discharges in various bladder regions and the external urethral sphincter (EUS) during voiding contractions, and to assess the functional role of myogenic modulation of the lower urinary tract (LUT) by ionotropic purinergic receptors containing the P2X3 subunit. METHODS: Female Sprague-Dawley rats were anesthetized with urethane, and implanted with a suprapubic catheter for open cystometry. Flexible microelectrodes were placed ventrally in the bladder dome, upper bladder, lower bladder, and bladder base, along with the middle section of the exposed EUS. Intravesical P2X3-containing receptors were blocked with AF-323, a specific P2X3-P2X2/3 receptor antagonist. A digital electrophysiology amplifier was used to record electrical and cystometric signals throughout the LUT. RESULTS: Electrical activity in the LUT started before effective voiding contractions. Bladder pressure and electrical waveforms showed consistent out-of-phase activity when compared with the recordings made at the EUS. This pattern was also observed during voiding contractions in the presence of AF-353, supporting the hypothesis that during bladder distension, activation of P2X3-containing receptors is required for voiding contractions. Furthermore, the inhibition of P2X3-containing receptors significantly decreased the amplitude of electrical signals in the urinary bladder, but not the base or EUS. CONCLUSIONS: Our results provide novel information about the regulation of the micturition process by P2X3-containing receptors located in the inner layers of the bladder.