Faster bladder filling in rats reduces detrusor overactivity but worsens (i.e., decreases) bladder compliance.

The impact of bladder filling rate on cystometric outcomes remains unclear. Clinically, faster bladder filling is believed to increase the likelihood of observing detrusor overactivity (DO) in those with bladder dysfunction, although evidence of this is lacking. We executed this study to clarify how changes in bladder filling rate impacted cystometric parameters. Urethane anesthetized female CD rats (n = 19) underwent bladder filling at five different fill rates, a baseline rate scaled to have a filling phase of approximately seven minutes (in line with our previous work), and scaled rates of 1/3x, 2x, 4x, and 8x that speed. Contrary to expectations, filling at faster rates decreased the likelihood of observing detrusor overactivity, with 4x and 8x filling rates demonstrating less detrusor overactivity than the baseline (1x) rate (P = 0.0091 for 4x and P = 0.019 for 8x). However, faster filling rates did decrease bladder compliance. Filling at 4x and 8x demonstrated decreased bladder compliance compared to 1x (P = 0.032 for 4x and P < 0.0001 for 8x). Finally, increasing the filling rate led to increases in bladder capacity at 4x (P = 0.034) and 8x (P = 0.0066) relative to 1x. These results suggest that contrary to expectations, faster filling may not be more effective at eliciting detrusor overactivity (i.e., not a better diagnostic approach). As reductions in detrusor overactivity and increases in bladder capacity are critical parameters for evaluating preclinical therapeutics, faster filling may impair the ability to demonstrate further improvements.

Outcomes of detrusorectomy in neurogenic bladders: A systematic review and meta-analysis.

INTRODUCTION: This systematic review and meta-analysis aims to assess the outcomes of detrusorectomy in children with neurogenic bladder (NB). MATERIALS AND METHODS: A search was performed in PUBMED, EMBASE and the Cochrane Library database in August 2023. The following search terms were used: "detrusorectomy", "detrusorotomy", "auto-augmentation". The two main primary outcomes were improvement in bladder capacity and bladder compliance after intervention. Outcomes were dichotomized into favorable and unfavorable. The secondary outcomes were the effect of postoperative bladder cycling on bladder compliance and bladder capacity and complications. RESULTS: 258 references were screened for inclusion, of these 242 were excluded. 8 of the remaining 16 studies were included for the qualitative and quantitative analysis. All studies were retrospective case series studies (165 patients). Median follow-up time varied between studies (1.75-11.1 years), while two studies reported a mean follow-up time of 8.1 years. Using a random effects meta-analysis, the overall rate for unchanged or improved bladder capacity was 95% (Proportion[CI]: 0.95 [0.61; 1.00]). The overall rate for improved bladder compliance after detrusorectomy was 67% (Proportion[CI]: 0.67 [0.26; 0.92)) (Summary Fig). In the bladder cycling group improved compliance was found in 89% of patients (Proportion[CI]: 0.89 [0.41; 0.99]), whereas it was 21% in the non-cycling group (Proportion[CI]: 0.21 [0.04; 0.61]) (p = 0.0552). Bladder cycling did not affect bladder capacity as the overall rate for unchanged or improved bladder capacity was 98% (Proportion[CI]: 0.98 [0.35; 0.92]) in the cycling and 73% (Proportion[CI]: 0.73 [0.46; 0.90]) in the non-cycling group (p > 0.05). Overall complications were encountered in 16 (9.7%) patients, with major complications (stones, bladder perforations) detected only in 5(3%) patients. DISCUSSION: Detrusorectomy leads to an improved bladder compliance in 67% of children. As such, detrusorectomy proves to be a viable procedure to enhance bladder compliance or to cure overactivity. Importantly, the beneficial effect of detrusorectomy on bladder compliance seems to be long-lasting. Bladder capacity remained unchanged or improved in almost all patients undergoing detrusorectomy. Postoperative bladder cycling was effective in improving bladder compliance outcome compared to the non-cycling group. Proper patient selection is the key to good postoperative outcomes. CONCLUSIONS: Detrusorectomy enhances bladder compliance in pediatric neurogenic bladders. Postoperative bladder cycling improves bladder compliance and the overall complication rate of the procedure is low. Therefore, detrusorectomy should be considered a valuable therapeutic option in the comprehensive management of neurogenic bladders in children.

CNN-based diagnosis model of children's bladder compliance using a single intravesical pressure signal.

Bladder compliance assessment is crucial for diagnosing bladder functional disorders, with urodynamic study (UDS) being the principal evaluation method. However, the application of UDS is intricate and time-consuming in children. So it'S necessary to develop an efficient bladder compliance screen approach before UDS. In this study, We constructed a dataset based on UDS and designed a 1D-CNN model to optimize and train the network. Then applied the trained model to a dataset obtained solely through a proposed perfusion experiment. Our model outperformed other algorithms. The results demonstrate the potential of our model to alert abnormal bladder compliance accurately and efficiently.

Factors associated with polyacrylamide hydrogel outcomes in women with stress urinary incontinence.

Knowledge of factors associated with superior outcomes in women treated with urethral bulking agents for stress urinary incontinence (SUI) remains limited. The aim of this study was to examine associations between post-treatment outcomes in women who had undergone polyacrylamide hydrogel injections for SUI, and physiological and self-reported variables captured during pre-treatment clinical evaluation. A cross-sectional study was undertaken in female patients treated for SUI with polyacrylamide hydrogel injections by a single urologist between January 2012 and December 2019. Post-treatment outcome data were gathered in July 2020 using the Patient Global Impression of Improvement (PGI-I), Urinary Distress Inventory-short form (UDI-6), Incontinence Impact Questionnaire (IIQ7), and International Consultation on Incontinence Questionnaire Short Form (ICIQ SF). All other data were gathered from women's medical records including pre-treatment patient-reported outcomes. Associations between post-treatment outcomes and pre-treatment physiological and self-reported variables were investigated using regression models. One hundred seven of the 123 eligible patients completed post-treatment patient-reported outcome measures. Mean age was 63.1 years (range 25-93 years), and median time between first injection and follow-up was 51 months (inter-quartile range 23.5-70 months). Fifty-five (51%) women had a successful outcome based on PGI-I scores. Women with type 3 urethral hypermobility pre-treatment were more likely to report treatment success (PGI-I). Poor bladder compliance pre-treatment was associated with greater urinary distress, frequency and severity (UDI-6 and ICIQ) post-treatment. Older age was associated with worse urinary frequency and severity (ICIQ) post-treatment. Associations between patient-reported outcomes and time between first injection and follow-up were trivial and not statistically significant. Severity of pre-treatment incontinence impact (IIQ-7) was associated with worse incontinence impact post-treatment. Type 3 urethral hypermobility was associated with a successful outcome, whereas pre-treatment incontinence impact, poor bladder compliance and older age were associated with poorer self-reported outcomes. Long-term efficacy appears to hold in those who responded to initial treatment.

Primary ablation versus urinary diversion in posterior urethral valve: Systematic review and meta-analysis.

PURPOSE: To determine differences in long-term kidney and bladder outcomes in boys with posterior urethral valves (PUV) managed by a primary valve ablation or primary urinary diversion. MATERIALS AND METHODS: A systematic search was performed in March 2021. Comparative studies were evaluated according to Cochrane collaboration recommendations. Assessed measures included kidney outcomes (chronic kidney disease, end-stage renal disease, kidney function) and bladder outcomes. Odds ratios (OR) and mean difference (MD) with 95% confidence interval (CI) were extrapolated from available data for quantitative synthesis. Random-effects meta-analysis and meta-regression were performed according to study design, and potential covariates were assessed with subgroup analysis. The systematic review was prospectively registered on PROSPERO (CRD42021243967). RESULTS: Thirty unique studies describing 1547 boys with PUV were included in this synthesis. Overall effect estimates demonstrate that patients undergoing primary diversion have significantly increased odds of developing renal insufficiency [OR 0.60, 95% CI 0.44, 0.80; p < 0.001]. However, when adjusting for baseline kidney function between intervention groups, there was no significant difference in long term kidney outcomes [p = 0.09, 0.35], or the development of bladder dysfunction or requiring clean-intermittent catheterization with primary ablation rather than diversion [OR 0.89, 95% CI 0.49, 1.59; p = 0.68]. CONCLUSIONS: Current low-quality evidence suggests that medium-term kidney outcomes in children are similar between primary ablation and primary diversion after adjusting for baseline kidney function, while bladder outcomes are highly heterogenous. Further research with covariate control is warranted to investigate sources of heterogeneity. LEVEL OF EVIDENCE: Level III.

Risk factors for upper urinary tract deterioration in adult patients with spina bifida.

PURPOSE: Neurogenic bladder associated with spina bifida disease remains a major cause for mortality or morbidity due to kidney damages. However, we currently do not know which urodynamic findings are associated with an higher risk of upper tract damages in spina bifida patients. The objective of the present study was to evaluate urodynamic findings associated with functional kidney failure and/or with morphological kidney damages. METHODS: A large single-center restrospective study was conducted in our national referral center for spina bifida patients using our patients' files. All urodynamics curves were assessed by the same examinator. Functional and/or morphological evaluation of the upper urinary tract were done at the same moment as the urodynamic exam (between 1 week before and 1 month after). Kidney function was assessed using creatinine serum levels or 24 h urinary creatinine levels (creatinine clearance) for walking patients, or with the 24 h urinary creatinine level for wheelchair-users. RESULTS: We included 262 spina bifida patients in this study. Fifty-five patients had a poor bladder compliance (21.4%) and 88 of them had detrusor overactivity (33.6%). Twenty patients had a stage 2 kidney failure (eGFR < 60 ml/min) and 81 patients out of 254 (30.9%) had an abnormal morphological examination. There were three urodynamic findings significantly associated with UUTD: bladder compliance (OR = 0.18; p = 0.007), Pdetmax (OR = 14.7; p = 0.003) and detrusor overactivity (OR = 1.84; p = 0.03). CONCLUSION: In this large series of spina bifida patients, maximum detrusor pressure and bladder compliance are the main urodynamic findings determinants of UUTD risk.

Urodynamic changes before and after endoscopic valve ablation in boys diagnosed with the posterior urethral valve without chronic renal failure.

INTRODUCTION: Current research on the posterior urethral valve (PUV) mainly focuses on the follow-up of bladder function after valve ablation. However, few studies exist on the changes in bladder function before and after valve ablation. OBJECTIVES: To investigate the urodynamic changes before and after PUV ablation and determine the effect of operation on bladder function, in patients. MATERIALS AND METHODS: The clinical records of 38 boys diagnosed with PUV and undergone urodynamic exams before and after valve ablation were retrospectively reviewed. In addition, differences in patients' radiographic studies and urodynamic characteristics between pre- and post-operation were evaluated. Moreover, the urodynamic data was compared using the paired t-test and all the data was expressed as means ± SEM. Additionally, p values less than 0.05 were considered to be statistically significant. RESULTS: All the patients were diagnosed with PUV and the follow-up period after operation ranged between 9 and 114 months. The urodynamic exams were performed about 6 months after operation. The results revealed that bladder compliance improved from 8.49 ± 4.73 to 13.31 ± 6.78 ml/cmH2O while the maximum detrusor pressure decreased from 95.18 ± 37.59 to 50.71 ± 21.71 cmH2O, after valve ablation. Additionally, there were significant differences in the pre- and post-operation values of bladder compliance and maximum detrusor pressure (p < 0.05). However, there were no significant differences in the pre- and post-operation values with regard to the residual urine volume, maximum bladder volume and maximum urinary flow rate (p > 0.05). CONCLUSIONS: The adequacy of the COPUM incision is necessary. But the study showed that endoscopic valve ablation couldn't by itself completely improve the bladder function of patients diagnosed with PUV. However, it was able to improve bladder compliance and decrease maximum detrusor pressure to a certain extent. However, bladder compliance still couldn't reach the normal level.

De Novo Detrusor Underactivity and Other Urodynamic Findings after Radical Prostatectomy: A Systematic Review.

Background and objectives: The aim of this systematic review is to evaluate the impact of radical prostatectomy (RP) on bladder function, with special attention towards detrusor underactivity investigated with the means of urodynamic evaluation. Materials and Methods: The review was performed in accordance with the PRISMA statement and was registered in the PROSPERO (ID#: CRD42020223480). The studied population was limited to men with prostate cancer who underwent urodynamic study prior to and after radical prostatectomy. Eight hundred twenty-seven studies were screened, with twenty-five finally included. A qualitative analysis was performed. Rates of detrusor underactivity (DU) before surgery were reported in eight studies and ranged from 1.6% to 75% (median of 40.8%). DU occurred de novo after RP in 9.1% to 37% of patients (median of 29.1%). On the other hand, preexisting DU resolved in 7% to 35.5% of affected men. Detrusor overactivity (DO) was the most frequently reported outcome, being assessed in 23 studies. The rate of DO preoperatively was from 5% to 76% (median of 25%). De novo was reported in 2.3-54.4% of patients (median of 15%) and resolved after RP in 19.6% to 87.5% (median of 33%) of affected patients. Baseline rates of bladder outlet obstruction (BOO) varied between studies from 19% to 59.3%, with a median of 27.8%. The most pronounced change after surgery was the resolution of BOO in 88% to 93.8% (median of 92%) of affected patients. Results: Rates of de novo impaired bladder compliance (IBC) varied from 3.2% to 41.3% (median of 13.3%), whereas the resolution of IBC was reported with rates ranging from 0% to 47% (median of 4.8%). Conclusions: BOO, DO, and DU are frequently diagnosed in men scheduled for RP. BOO is improved after RP in most patients; however, there is still a substantial rate of patients with de novo DU as well as DO which may impair functional outcomes and quality of life.

Telmisartan inhibits bladder smooth muscle fibrosis in neurogenic bladder rats.

Hypertension is associated with bladder symptoms. The present study investigated whether an angiotensin receptor blocker could improve the symptoms and pathological changes associated with a neurogenic bladder (NB). A Sprague-Dawley rat model of NB was constructed. Rats in the sham and model groups were gavaged with saline, and rats in the treatment group were gavaged with telmisartan. Urodynamic parameters, including maximum cystometric capacity, residual urine volume, bladder wet weight, bladder compliance and detrusor pressure, were detected. Masson and H&E staining were performed to assess bladder fibrosis and histopathological changes. The expression levels of basic fibroblast growth factor (bFGF), TGF-ß1, Collagen I, Collagen III, and α-smooth muscle actin (α-SMA) were also measured by reverse transcription-quantitative PCR, western blotting and immunohistochemistry. The model rats exhibited symptoms and pathological changes associated with NB. Treatment with telmisartan reduced maximum cystometric capacity, residual urine volume, bladder compliance and bladder wet weight, and increased detrusor pressure in model rats. The tissue staining results showed that telmisartan exerted an antifibrotic effect. In addition, telmisartan inhibited the expression of bFGF, TGF-ß1, Collagen I, Collagen III and α-SMA in model rats. Therefore, the results of the present study indicated that telmisartan may serve as a potential therapeutic agent for NB.

Design of a rapid diagnostic model for bladder compliance based on real-time intravesical pressure monitoring system.

OBJECTIVE: The diagnosis of bladder dysfunction for children depends on the confirmation of abnormal bladder shape and bladder compliance. The existing gold standard needs to conduct voiding cystourethrogram (VCUG) examination and urodynamic studies (UDS) examination on patients separately. To reduce the time and injury of children's inspection, we propose a novel method to judge the bladder compliance by measuring the intravesical pressure during the VCUG examination without extra UDS. METHODS: Our method consisted of four steps. We firstly developed a single-tube device that can measure, display, store, and transmit real-time pressure data. Secondly, we conducted clinical trials with the equipment on a cohort of 52 patients (including 32 negative and 20 positive cases). Thirdly, we preprocessed the data to eliminate noise and extracted features, then we used the least absolute shrinkage and selection operator (LASSO) to screen out important features. Finally, several machine learning methods were applied to classify and predict the bladder compliance level, including support vector machine (SVM), Random Forest, XGBoost, perceptron, logistic regression, and Naive Bayes, and the classification performance was evaluated. RESULTS: 73 features were extracted, including first-order and second-order time-domain features, wavelet features, and frequency domain features. 15 key features were selected and the model showed promising classification performance. The highest AUC value was 0.873 by the SVM algorithm, and the corresponding accuracy was 84%. CONCLUSION: We designed a system to quickly obtain the intravesical pressure during the VCUG test, and our classification model is competitive in judging patients' bladder compliance. SIGNIFICANCE: This could facilitate rapid auxiliary diagnosis of bladder disease based on real-time data. The promising result of classification is expected to provide doctors with a reliable basis in the auxiliary diagnosis of some bladder diseases prior to UDS.

Regulation of bladder dynamic elasticity: a novel method to increase bladder capacity and reduce pressure using pulsatile external compressive exercises in a porcine model.

PURPOSE: Dynamic elasticity is a biomechanical property of the bladder in which muscle compliance can be acutely adjusted through passive stretches and reversed with active contractions. The aim of this study was to determine if manipulating dynamic elasticity using external compression could be used as a novel method to acutely increase bladder capacity and reduce bladder pressure in a porcine model. METHODS: Ex vivo experiment: bladders underwent continuous or pulsatile compression after establishing a reference pressure at bladder capacity. Bladders were then filled back to the reference pressure to determine if capacity could be acutely increased. In-vivo experiments: bladders underwent five cycles of pulsatile external compression with ultrasound confirmation. Pre and post-compression pressures were measured, and pressure was measured again 10 min post-compression. RESULTS: Ex vivo experiment: pulsatile compression demonstrated increased bladder capacity by 16% (p = 0.01). Continuous compression demonstrated increased capacity by 9% (p < 0.03). Comparison of pulsatile to continuous compression showed that the pulsatile method was superior (p = 0.03). In-vivo experiments: pulsatile external compression reduced bladder pressure by 19% (p < 0.00001) with a return to baseline 10 min post-compression. CONCLUSIONS: These results suggest that regulation of bladder dynamic elasticity achieved with external compression can acutely decrease bladder pressure and increase bladder capacity. Pulsatile compression was found to be more effective as compared to continuous compression. These results highlight the clinical potential for use of non-invasive pulsatile compression as a therapeutic technique to increase bladder capacity, decrease bladder pressure, and reduce the symptoms of urinary urgency.

Non-invasive assessment of urinary bladder compliance using ultrasound: first validation study based on clinical urodynamic study.

BACKGROUND: This study aims to validate a recently introduced non-invasive method, ultrasound bladder vibrometry (UBV), for the assessment of detrusor compliance in patients with neurogenic bladders. METHODS: The study was carried out on 79 adult patients with neurogenic bladders (60 male and 19 female). The UBV test was performed on each patient to measure the Lamb wave group velocity (cg ) in the anterior bladder wall at every 50mL volume increment throughout the filling phase. Bladder compliance was assessed based on the trend of Lamb wave group velocity squared (cg 2 ) versus volume. A compliance index was defined to differentiate between the compliant and non-compliant bladders. Results of the UBV compliance assessment were validated using the readings of the corresponding urodynamic studies as the clinical gold standard. RESULTS: The Patients' bladders were divided into non-compliant and compliant groups by an experienced urologist using the information in the urodynamic study (UDS) recordings. The compliance index defined on the basis of cg 2 showed a significant difference (P<0.008) between the compliant and non-compliant groups. The areas under the receiver operating characteristic curve were 0.813, with 95% CI ranging from 0.709 to 0.892. Under the optimal criterion, the bladder was considered as non-compliant if the compliance index was less than 100 mL∙s2/m2, resulting in a sensitivity and specificity of 86.4% and 71.9%, respectively. CONCLUSIONS: The results of this study demonstrate that UBV can be used as a non-invasive method for the determination of bladder compliance; thus, it can potentially serve as an alternative method to UDS for the appropriate patient groups.

Will repeated botulinum toxin A improve detrusor overactivity and bladder compliance in patients with chronic spinal cord injury?

Chronic spinal cord injury (SCI) can induce neurogenic detrusor overactivity (NDO), leading to urinary incontinence and renal damage due to low bladder compliance and high detrusor pressure during the storage and voiding of urine. In 2011, Botox® (onabotulinumtoxinA, botulinum neurotoxin serotype A [BoNT-A]) was approved by the Food and Drug Administration for the treatment of NDO. Intradetrusor injection of BoNT-A has been shown to have clinical utility for the treatment of urinary incontinence, with consequent improvements in quality of life for patients. In the past 20 years, this treatment has been shown to be an effective treatment for patients with SCI refractory to antimuscarinic medication. The present review focused on publications in MEDLINE/PubMed relating to botulinum toxin to evaluate the treatment outcomes of repeated injection of BoNT-A, the mechanisms of action, results of clinical and urodynamic studies, and adverse effects.

A single-blind randomized control trial of trigonal versus nontrigonal Botulinum toxin-A injections for patients with urinary incontinence and poor bladder compliance secondary to spinal cord injury.

Objective: To evaluate the effect of trigonal Botulinum toxin-A (BTX-A) injections on patients with urinary incontinence (UI) and poor bladder compliance (BC) secondary to spinal cord injury (SCI).Design: A single-blind randomized control trial.Setting: Department of urology in three hospitals.Participants: SCI patients with UI and poor BC were randomly assigned to either the experimental group or the control group.Interventions: The experimental group received an injection of 240 U BTX-A into the detrusor plus 60 U BTX-A into the trigone, while the control group received 300 U BTX-A into the detrusor sparing the trigone.Outcome Measures: Video urodynamic outcomes, including vesicoureteric reflux (VUR), detrusor leak point pressure (DLPP), and detrusor leak point volume (DLPV), were measured at baseline and week 12. UI episodes, voiding volume, and Incontinence Quality of Life (I-QoL) were assessed at baseline, week 2, 4, 8 and 12.Results: No patient reported new-onset VUR. Compared with baseline data, a significant improvement was achieved in both groups, whereas compared with DLPP and DLPV, a significant difference was noted between the two groups 12 weeks after injection. In the experimental group, the improvement of mean weekly UI episodes, voiding volume, and I-QoL were significantly better than those in the control group at 4, 8, and 12 weeks, respectively (all P < 0.05). Systemic complications of BTX-A injection were not reported.Conclusion: Trigonal BTX-A injection is more effective and safer than nontrigonal BTX-A injection for SCI patients with UI secondary to neurogenic-poor BC and does not result in VUR.

Will detrusor acontractility recover after medical or surgical treatment? A longitudinal long-term urodynamic follow-up.

AIMS: Patients with urinary retention due to detrusor acontractility (DA) might regain voiding efficiency (VE) after treatment. This study investigated the long-term outcomes and predictors of recovery following treatment. METHODS: A total of 32 patients with DA were retrospectively identified and enrolled. DA was defined by Pdet .Qmax = 0 cmH2 O and postvoid residual (PVR) > 300 ml determined through videourodynamic study (VUDS). All patients received medical or surgical treatment and were followed up for at least 3 months, during which repeat VUDS was conducted. Detrusor contractility recovery was confirmed when patients were able to void with a Pdet .Qmax ≥ 10 cmH2 O after treatment. RESULTS: Our patients comprised 22 women and 10 men (mean age, 73.2 ± 9.7 years; mean follow-up duration, 1.6 ± 1.8 [0.3-7.4] years). Follow-up VUDS revealed that 14 (43.9%) patients recovered from detrusor contractility, with five patients recovering within 1 year and nine after 1 year. Pdet .Qmax , voided volume, PVR, maximum flow rate, and VE significantly improved in both the recovery and nonrecovery groups. The recovery group had significantly better VE (p = .039) and significantly lower bladder compliance (74.2 ± 83.2 vs. 119 ± 82.6; p = .007) than the nonrecovery group. Receiver operating characteristic (ROC) analysis revealed an optimum bladder compliance cutoff value of <80 ml/cmH2 O for predicting detrusor contractility recovery with an area under the ROC curve of 0.780. CONCLUSIONS: Among the included patients with DA, 43.9% had detrusor contractility recovery after treatment, with bladder compliance of <80 ml/cmH2 O predicting bladder function recovery.

Is isolated bladder outlet obstruction associated with hydronephrosis? A database analysis.

AIMS: To examine whether isolated bladder outlet obstruction in the absence of associated lower urinary tract abnormality results in hydronephrosis. Isolated obstruction causes a brief rise in bladder pressure that might not trigger hydronephrosis. METHODS: Data included adult men who underwent urodynamics for refractory non-neurogenic lower tract symptoms between 2011 and 2020. International Continence Society indices for obstruction (bladder outlet obstruction index [BOOI] ≥ 40) and underactivity (bladder contractility index [BCI] < 100) were calculated. Storage abnormality was defined as detrusor overactivity (DO) or poor compliance (<20 ml/cm H2 0). Isolated obstruction was defined as BOOI ≥ 40, BCI ≥ 100 and no storage abnormality. Nonparametric tests using R program (3.5.0) applied (p < .05 significant). Logistic regression analyses were performed to study the relationships of hydronephrosis with lower urinary tract function. RESULTS: A total 1596 men (range, 18-91 years; median, 51.0 years; Q3, 64.0 years; Q1, 34.0 years) were eligible. Hydronephrosis was noted in 274 (17.2%). A total of 45.4% were obstructed, 52.3% were underactive and 41.7% had storage abnormality. Storage abnormality (odds ratios [OR], 2.05; 95% confidence interval [CI]: 1.56, 2.69; p < .001) and bladder contractility (OR, 1.68; 95% CI, 1.25-2.26; p < .001) but not obstruction (OR, 1.07; 95% CI, 0.80-1.44; p = .634) was associated with hydronephrosis. Of eight possible combinations, men with BOO ≥ 40, BCI ≥ 100 and storage abnormality had highest probability of hydronephrosis (OR, 0.29; 95% CI, 0.24-0.33). Subanalysis showed that poor compliance (OR, 3.39; 95% CI, 2.49-4.60; p < .001) but not DO was associated with hydronephrosis. Younger age and higher postvoid residual urine were also associated with hydronephrosis. CONCLUSIONS: In adult men with refractory non-neurogenic lower urinary tract symptoms, isolated bladder outlet obstruction is not associated with hydronephrosis.

Study of correlation of urodynamic profile with symptom scoring and ultrasonographic parameters in patients with benign prostatic hyperplasia.

CONTEXT: Urodynamic study (UDS) and ultrasonography (USG) both are established investigations to assess the patients of benign prostatic hyperplasia (BPH). It is known that the prostate mass (PM) and post-void residual urine volume (PVR) are not significantly related to the patients' symptoms and degree of obstruction; however, the relation between the UDS, USG and patient's International Prostate Symptom Scoring (IPSS) has not been defined. AIMS: To correlate the urodynamic parameters with IPSS, PM and PVR in patients with lower urinary tract symptoms (LUTS) suggestive of BPH. SETTINGS AND DESIGN: An observational study carried out as a thesis project. METHODS AND MATERIALS: Thirty male patients aged more than 40 years with LUTS suggestive of BPH were selected and underwent USG, UDS and IPSS. In UDS, the parameters studied were the maximum flow rate (Qmax), detrusor pressure (Pdet) and bladder compliance (BC). PM and PVR were studied in the USG. STATISTICAL ANALYSIS USED: IBM Statistical Package for the Social Sciences (SPSS) software version 16 (SPSS Inc., Chicago, USA). Pearson's correlation and two-sided significance levels were determined. RESULTS: 1. Significant negative correlation between Qmax and PVRUSG (r = -0.404, P = 0.027); PMUSG (r = -0.655, P = <0.001) and IPSS (r = -0.563, P = 0.001). 2. Significant positive correlation between Pdet and PVRUSG (r = 0.535, P = 0.002); PMUSG (r = 0.719, P = <0.001) and IPSS (r = 0.649, P = <0.001). 3. Significant negative correlation between BC and PVRUSG (r = -0.490, P = 0.006); PMUSG (r = -0.654, P = <0.001) and IPSS (r = -0.667, P = <0.001). CONCLUSIONS: UDS has a significant correlation with IPSS and USG findings and urodynamic parameters give a more specific diagnosis in BPH patients when it is combined with USG and IPSS.

Comparative-fill urodynamics in individuals with and without detrusor overactivity supports a conceptual model for dynamic elasticity regulation.

AIMS: Dynamic elasticity was previously identified in individuals with overactive bladder (OAB) using comparative-fill urodynamics (UD) and is a biomechanical mechanism for acutely regulating detrusor wall tension. On the basis of this data, a conceptual model of dynamic elasticity regulation mediated through a balance of passive mechanisms and active contractions was constructed. The present study tested this model by determining whether individuals with detrusor overactivity (DO) exhibit less dynamic elasticity than individuals without DO. METHODS: Individuals with and without urgency based on International Consultation on Incontinence Questionnaire-OAB surveys were prospectively enrolled in a comparative-fill UD study. An initial fill defined the presence or absence of DO and determined cystometric capacity. Three additional fills were employed with either passive emptying via a catheter or active voiding. To identify dynamic elasticity, average filling pressures (Pves ) were compared for fill 1 (before strain softening), fill 2 (after strain softening), and fill 3 (after active void). A dynamic elasticity index was defined. RESULTS: From 28 participants, those without DO showed decreased Pves during filling after strain softening and restored Pves during filling following active voiding, revealing dynamic elasticity. Participants with DO did not show dynamic elasticity. A dynamic elasticity index less than 1.0 cmH2 O/40% capacity was identified in 2 out of 13 participants without DO and 9 out of 15 with DO, revealing a significant association between DO and reduced/absent dynamic elasticity (P = .024). CONCLUSIONS: This study supports a conceptual model for dynamic elasticity, a mechanism to acutely regulate detrusor wall tension through a balance of competing active contractile and passive strain mechanisms. Improved understanding of this mechanistic model may help us to identify novel treatment strategies for OAB.

Effects of the combination of vibegron and imidafenacin on bladder function in urethane-anesthetized rats.

The combination of a ß3-adrenoceptor agonist and an antimuscarinic agent was revealed to be more effective than monotherapy for patients with overactive bladder and in animal models. However, its influence on voiding functions has not been well documented. Therefore, during intermittent-cystometry, we studied the effects of vibegron (a novel ß3-adrenoceptor agonist) and imidafenacin (an antimuscarinic agent) alone to determine their dose levels for the combination study. Then, the effects of the combination on voiding functions were investigated in urethane-anesthetized rats (1.0 g/kg s.c.). Independently, vibegron (0.3-3 mg/kg, i.v.) and imidafenacin (0.001 and 0.003 mg/kg, i.v.) dose-dependently increased bladder capacity and voided volume, without affecting voiding functions such as residual volume, voiding efficiency, and micturition pressure. However, vibegron also increased bladder compliance. The combination of vibegron (3 mg/kg) and imidafenacin (0.003 mg/kg) significantly increased bladder capacity and voided volume when compared to those with monotherapy using each individually. The combination did not change residual volume, voiding efficiency, and micturition pressure, compared to those in the vehicle group. We identified no responses in resiniferatoxin (RTX)-treated rats, as opposed to those identified after administering vibegron (3 mg/kg), imidafenacin (0.003 mg/kg), or both to non-RTX-treated rats. These outcomes might have resulted from the combination of the increased effect of vibegron on bladder compliance and the inhibitory effect of both vibegron and imidafenacin on the activation of bladder afferent nerves.

Layer-dependent role of collagen recruitment during loading of the rat bladder wall.

In this work, we re-evaluated long-standing conjectures as to the source of the exceptionally large compliance of the bladder wall. Whereas these conjectures were based on indirect measures of loading mechanisms, in this work we take advantage of advances in bioimaging to directly assess collagen fibers and wall architecture during biaxial loading. A custom biaxial mechanical testing system compatible with multiphoton microscopy was used to directly measure the layer-dependent collagen fiber recruitment in bladder tissue from 9 male Fischer rats (4 adult and 5 aged). As for other soft tissues, the bladder loading curve was exponential in shape and could be divided into toe, transition and high stress regimes. The relationship between collagen recruitment and loading curves was evaluated in the context of the inner (lamina propria) and outer (detrusor smooth muscle) layers. The large extensibility of the bladder was found to be possible due to folds in the wall (rugae) that provide a mechanism for low resistance flattening without any discernible recruitment of collagen fibers throughout the toe regime. For more extensible bladders, as the loading extended into the transition regime, a gradual coordinated recruitment of collagen fibers between the lamina propria layer and detrusor smooth muscle layer was found. A second important finding was that wall extensibility could be lost by premature recruitment of collagen in the outer wall that cut short the toe region. This change was correlated with age. This work provides, for the first time, a mechanistic understanding of the role of collagen recruitment in determining bladder extensibility and capacitance.