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Benign prostate hyperplasia is the leading cause of lower urinary tract symptoms due to bladder outlet obstruction (BOO) in elderly male patients. The impact of prostate volume (PV) on clinical and urodynamic characteristics was evaluated in those patients with BOO requiring prostate de-obstruction maneuvers in this study. We retrospectively reviewed the clinical data of 301 patients underwent transurethral resection of prostate due to combination with urinary retention (UR) alone and bladder stone (BS) alone. The present study investigated the differences of subjective symptoms, sonographic parameters, and urodynamic characters and assessed the proportion of UR to BS as well as the incidence of detrusor underactivity (DU) in those patients according to PV. There was not a difference of age, international prostate symptoms scores, post-voiding residual, and peak flow rate (Qmax) among 3 groups (all P > .05), whereas increasing of intravesical prostate protrusion (IPP), bladder wall thick (BWT), detrusor pressure at Qmax, bladder contractility index, bladder outlet obstruction index (BOOI), and quality of life scores with enlargement of PV was found (all P < .05). Correlations between PV and IPP (R = 0.251), Qmax (R = -0.188), post-voiding residual (R = 0.215), BWT (R = 0.170), and quality of life scores (R = 0.165) at large prostate and relationships between BWT and BOOI (R = 0.246) and bladder contractility index (R = 0.239) in moderate prostate as well as IPP and BOOI (R = 0.204) in large prostate were significantly found (all P < .05). Significant higher proportion of UR was found in patients with moderate (18%) and large prostate (47.6%) when compared to that of small prostate (3.7%), whereas higher proportion of BS was found in patients with small prostate (96.7%) compared to that of moderate (82%) and large (52.4%) prostate. Lower incidence of DU was discovered in large prostate (31.9%) compared with small (55.6%) and moderate (47.2%) prostate. BOO patients with small prostate were associated with less severity of BOO but higher incidence of DU and had a tendency of occurrence of BS, which gave a support for the theory that multifactor involved in the formation of BS rather than BOO only., Competing Interests: The author have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Purpose: To intelligently diagnose whether there is bladder outlet obstruction (BOO) in female with decent detrusor contraction ability by focusing on urodynamic study (UDS) data., Materials and Methods: We retrospectively reviewed the UDS data of female patients during urination. Eleven easily accessible urinary flow indicators were calculated according to the UDS data of each patient during voiding period. Eight diagnosis models based on back propagation neural network with different input feature combination were constructed by analyzing the correlations between indicators and lower urinary tract dysfunction labels. Subsequently, the stability of diagnostic models was evaluated by five-fold cross-validation based on training data, while the performance was compared on test dataset., Results: UDS data from 134 female patients with a median age of 51 years (range, 27-78 years) were selected for our study. Among them, 66 patients suffered BOO and the remaining were normal. Applying the 5-fold cross-validation method, the model with the best performance achieved an area under the receiver operating characteristic curve (AUC) value of 0.949±0.060 using 9 UDS input features. The accuracy, sensitivity, and specificity for BOO diagnosis model in the testing process are 94.4%, 100%, and 89.3%, respectively., Conclusions: The 9 significant indicators in UDS were employed to construct a diagnostic model of female BOO based on machine learning algorithm, which performs preferable classification accuracy and stability., Competing Interests: The authors have nothing to disclose., (© The Korean Urological Association.)

Introduction: Micturition physiology differs in men and women. However, the results in standard urodynamic studies in women with lower urinary tract symptoms (LUTS) were extrapolated from studies in men. Nowadays, the only validated nomogram for females is Solomon-Greenwell's. However, it only evaluated bladder outlet obstruction (BOO) without considering detrusor underactivity (DU). This study aims to create a nomogram that includes an evaluation of DU and BOO in nonneurogenic women and validate it against videourodynamic studies along with other nomograms., Materials and Methods: For the first analysis (creation cohort), we included 183 women with LUTS who underwent videourodynamic study between 2022 and 2023. Exclusion criteria were females with neurologic diseases, renal transplantation, and trouble performing the flow-pressure study. Baseline characteristics of the patients, urodynamic parameters, and classifications on different nomograms and indexes were evaluated. A logistic regression found Qmax and PdetQmax as predictors for DU and BOO. The Barco-Castillo nomogram was created by clustering analysis and adjusted by the results of the logistic regression. A second (test) cohort was evaluated from 2023 to 2024, including 142 patients for the validation of the nomogram. A p < 0.05 was considered significant., Results: All urodynamic parameters were compared between both cohorts, with no significant differences. The median age of the creation cohort was 50 years old (interquartile range [IQR] 39-63). All patients had LUTS and a previous standard urodynamic study without a clear diagnosis. The cluster analysis had a p < 0.05 for two groups of BOO (yes/no) and two of DU (yes/no). We created the graph based on the logistic regression results and adjusted it according to the data. The median age of the test cohort was 44 years old (IQR 33.75-59) and had the same indication for the videourodynamic study. The receiver operating characteristic (ROC) curve for BOO showed an accuracy of 85.4% for Barco-Castillo nomogram, 68.5% for Blaivas-Groutz, 58.1% for Solomon-Greenwell, 57.1% for BOOI, and 50% for LinPURR. For DU, accuracy was 80.5% for PIP-1, 80.2% for Barco-Castillo, 76.6% for BCI, and 70.1% for LinPURR., Conclusions: When evaluating women's urodynamic studies, it is important to focus on female physiology and discourage the use of parameters previously standardized in men. We encourage using the new Barco-Castillo nomogram to determine BOO and DU in women as the currently easiest and more accurate tool., (© 2024 Wiley Periodicals LLC.)

Purpose: Our study aimed to develop a noninvasive model using a combination of the set of clinical data and uroflowmetry (UFL) to differentiate between detrusor underactivity (DU) and bladder outlet obstruction (BOO) in non-neurogenic male patients with lower urinary tract symptoms (LUTS)., Methods: Data from 229 men with LUTS, diagnosed with DU or BOO on a pressure-flow study (PFS), were retrospectively analyzed, including medical history, Core Lower Urinary Tract Symptoms score (CLSS) questionnaire, UFL and PFS. Uni- and multivariate logistic regression were utilized for the prediction analyses., Results: Of the cohort, 128 (55.9%) patients were diagnosed with DU. A multivariate logistic regression analysis identified less prevalent nocturia (OR 0.27, p < 0.002), more prevalent intermittency (OR 2.33, p = 0.03), less prevalent weak stream (OR 0.14, p = 0.0004), lower straining points in CLSS (OR 0.67, p = 0.02), higher slow stream points in CLSS (OR 1.81, p = 0.002), higher incomplete emptying points in CLSS (OR 1.31, p < 0.02), lower PVR ratio (OR 0.20, p = 0.03), and present features of fluctuating (OR 2.00, p = 0.05), fluctuating-intermittent (OR 3.09, p < 0.006), and intermittent (OR 8.11, p = 0.076) UFL curve shapes as independent predictors of DU. The above prediction model demonstrated satisfactory accuracy (c-index of 0.783)., Conclusion: Our 10-factor model provides a noninvasive approach to differentiate DU from BOO in male patients with non-neurogenic LUTS, offering a valuable alternative to invasive PFS., (© 2024. The Author(s).)

Introduction: Bladder outflow obstruction (BOO) is a urethral resistance (UR) at a level above a clinically relevant threshold. UR is currently graded in terms of the existence and severity of the BOO based on maximum flowrate and associated detrusor pressure only. However, the pressure-flow relation throughout the course of voiding includes additional information that may be relevant to identify the type of BOO. This study introduces a new method for the distinction between the provisionally called compressive and constrictive types of BOO and relates this classification to underlying patient and urodynamic differences between those BOO types., Methods: In total, 593 high-quality urodynamic pressure-flow studies in men were included in this study. Constrictive BOO was identified if the difference Δp between the actual minimal urethral opening pressure (p muo ) and the expected p muo according to the linearized passive urethral resistance relation (linPURR) nomogram was >25 cmH 2 O. Compressive BOO is identified in the complementary case where the pressure difference Δp ≤ 25 cmH 2 O. Differences in urodynamic parameters, patient age, and prostate size were explored., Results: In 81 (13.7%) of the cases, constrictive BOO was found. In these patients, the prostate size was significantly smaller when compared to patients diagnosed with compressive BOO, while displaying a significantly lower maximum flowrate, higher detrusor pressure at maximal flowrate and more postvoid residual (PVR)., Conclusion: This study is an initial step in the validation of additional subtyping of BOO. We found significant differences in prostate size, severity of BOO, and PVR, between patients with compressive and constrictive BOO. Subtyping of voiding-outflow dynamics may lead to more individualized management in patients with BOO., (© 2024 The Author(s). Neurourology and Urodynamics published by Wiley Periodicals LLC.)

Objective: Female voiding dysfunction with cystocele have been widely studied, but there are no data regarding women without cystoceles. The present study aimed to evaluate the prevalence of detrusor underactivity (DU) and bladder outlet obstruction (BOO) without cystoceles in a large sample size., Methods: This was a retrospective cohort study. Between April 1996 and September 2018, 602 neurologically intact women with voiding dysfunction without cystoceles were enrolled. Detrusor pressure (DU) at the maximum flow rate (PdetQmax) <20 cmH 2 O, maximum flow rate (Qmax) <15 mL/s, and a bladder voiding efficiency <90% and BOO (PdetQmax ≥40 cmH 2 O and Qmax <12 mL/s) were diagnosed by urodynamic study. Otherwise, a non-DU/BOO diagnosis was made. The prevalence of DU and BOO was the primary outcome. The secondary outcomes were the analyses of the differences between these three groups in objective UDS parameters and subjective questionnaires and bladder diary parameters., Results: This study included 100 (17%) women with DU, 60 (10%) with BOO, and 442 (73%) with a non-DU/BOO diagnosis. DU increased with age, but BOO decreased as age increased. The women in the DU group were older, had higher parity and pad weights, and lower PdetQmax, maximum urethral closure pressure, and functional profile length than the BOO group. The urodynamic findings did not correlate well to subjective questionnaire parameters. None of the symptoms revealed a significant difference between the groups. The retrospective design was the limitation of the study., Conclusion: The prevalence of DU increased with age in women with voiding dysfunction without advanced cystoceles. Conversely, BOO decreased with age. Prevalence intersected in the fourth decade. Diagnosis requires urodynamic evaluation, as subjective symptoms are inconclusive., (© 2024 The Author(s). International Journal of Gynecology & Obstetrics published by John Wiley & Sons Ltd on behalf of International Federation of Gynecology and Obstetrics.)

This study aims to present age-stratified prevalence of women with lower urinary tract symptoms (LUTS) but without cystocele and predict detrusor underactivity (DU) or bladder outlet obstruction (BOO). Between 2005 and 2020, we reviewed women who visited the medical center with LUTS but without cystocele. Positive voiding dysfunction (VD) symptoms were defined as any one or more of the positive descriptions of weak urinary stream, intermittency, strain to urination, and sensation of not emptying. A total of 1,886 women were included in this study. 189 (10.0%) women were diagnosed with DU, and 77 (4.1%) women had BOO. Multivariate logistic regression analysis found that voided volume and VD symptoms were independent predictors for BOO. ROC curve analyses could predict BOO by voided volume ≤ 220 mL derived from uroflowmetry and the presence of VD symptoms with an area under a curve of 0.83. Age and voided volume could predict DU with an area under a curve of 0.82. We found a higher percentage of BOO in women with positive VD symptoms. A non-invasive uroflowmetry with voided volume (≤ 220 mL) and the presence of VD symptoms can predict BOO. DU could be predicted by age and voided volume., (© 2024. The Author(s).)

Objective: Detrusor underactivity (DU) is a common cause of lower urinary tract symptoms (LUTS). To date, no consensus has been reached on the urodynamic criteria for defining DU. We previously proposed the area under the curve of the Watts factor (WF-AUC) as a new parameter for diagnosing DU. By comparing previously reported five criteria for DU and WF-AUC, we analyzed whether the WF-AUC could assess detrusor contraction in women with LUTS., Methods: Using urodynamic data of consecutive 77 women with LUTS, first, we classified DU based on previously reported five criteria. Second, we assessed the potential correlation between multiple parameters and WF-AUC. Third, receiver operating characteristic curve analysis was performed to determine the cutoff value of WF-AUC for diagnosing DU based on previously reported five criteria. Fourth, a linear regression analysis was conducted and compared using multiple criteria and female bladder outlet obstruction index (BOOIf)., Results: WF-AUC was positively correlated with the maximum values of WF, bladder contractility index (BCI), and projected isovolumetric pressure 1 (PIP1) with correlation coefficients of 0.63, 0.57, and 0.34, respectively. AUC for diagnosing DU based on previously reported five criteria ranging from 0.773 to 0.896 with different cutoff values of AUC-WF. The Spearman's correlation test revealed that BOOIf was significantly correlated with BCI, but not W max , PIP1 and WF-AUC., Conclusions: This study demonstrated the non-inferiority of the WF-AUC compared to previously reported criteria for defining DU. Depending on the cutoff value, the WF-AUC could appropriately evaluate women with DU, regardless of the presence of BOO., (© 2024 The Japanese Urological Association.)

Background and Objective: Symptomatic benefit and urodynamic obstruction relief represent relevant outcomes of therapies for lower urinary tract symptoms suggestive of benign prostatic hyperplasia (LUTS/BPH). We summarized evidence from studies concurrently assessing variations in terms of symptoms severity and invasive urodynamic measures of obstruction following medical and surgical therapies for LUTS/BPH., Methods: We performed a systematic review of PubMed, Scopus, and Web of Science in June 2023., Key Findings and Limitations: We identified 29 publications: 14 (872 patients) and 15 (851 patients) studies addressing medical and surgical therapies, respectively. The mean percentage total International Prostate Symptom Score (IPSS) improvements ranged from -2.5% to 56.3% and from 35.1% to 82.1% following medical and surgical therapies, respectively. The corresponding mean percentage Bladder Outlet Obstruction Index (BOOI) improvements ranged from 7.8% to 53.5% and from 22.4% to 138.6%, respectively. Holmium laser enucleation of the prostate (HoLEP) provided IPSS improvements in the higher range and the greatest BOOI reduction., Conclusions and Clinical Implications: Globally, based on available evidence, more pronounced symptomatic benefits are observed following treatments providing greater deobstructive effect. In detail, patients undergoing surgery exhibit greater IPSS and BOOI improvements than those receiving medical therapy., (Copyright © 2024 European Association of Urology. Published by Elsevier B.V. All rights reserved.)

Aims: To address the predictive factors of a successful voiding after bladder outflow resistance reduction surgery (BORRS) in men presenting with acute or chronic urinary retention (UR)., Methods: A think tank (TT) of ICI-RS was gathered in 2023, Bristol, UK, to discuss several aspects of the problem, such as the pathophysiology of UR, the clinical and urodynamic evaluation of men with UR and whether it is possible to predict which men will be able to successfully void after treatment with contemporary surgical options., Results: The TT agreed that successful voiding after BORRS depends on several factors but that a strong recommendation cannot be made regarding preoperative evaluation and whether there are predictive factors of success because of the heterogeneity of patients and methodology in published trials. The diagnosis of obstruction in men with UR may be challenging when there is apparent reduced detrusor contraction during urodynamic studies. Even in the absence of bladder contractility there is documentation of such cases that have voided adequately after BORRS. Still, detrusor underactivity and inadequate relief of prostatic obstruction are the main causes of an unsuccessful voiding after BORRS. Conventional resection and enucleation methods remain the most successful surgeries in relieving UR in men, whereas the efficacy of minimally invasive surgical treatments needs to be assessed further., Conclusion: Research is needed to understand the pathophysiology of UR and the predictors of successful voiding after different types of BORRS in men with UR., (© 2024 Wiley Periodicals LLC.)

Objective: To develop and validate a simple prediction model to diagnose female bladder outlet obstruction (fBOO) because of the invasive nature of standard urodynamic studies (UDS) for diagnosing fBOO., Methods: We retrospectively analyzed the data of 728 women who underwent UDS at Tongji Hospital between 2011 and 2021. The definition of fBOO was P det.Qmax  - 2.2 × Q max  > 5 (BOOIf > 5). Independent predictive factors of fBOO were determined by multivariable logistic regression analysis. These predictive factors were incorporated into a predictive model to assess the risk of fBOO., Results: Of the 728 patients, 249 (34.2%) were identified as having fBOO and these women were randomly assigned to two groups, a model development group and a model validation group. Multivariate logistic regression demonstrated that age, Q max , flow time, and voiding efficiency were independent risk factors for fBOO. The predictive model of fBOO showed a satisfactory performance, with area under the curve being 0.811 (95% confidence interval [CI] 0.771-0.850, P < 0.001), which was confirmed to be 0.820 (95% CI 0.759-0.882, P < 0.001) with external validation. The calibration curve indicated that the predicted probability had an excellent correspondence to observed frequency. Decision curve analysis demonstrated a greater clinical net benefit compared with the strategies of treat all or treat none when the predicted risk was in a range of 3% and 75%., Conclusion: A novel predictive model of fBOO was developed and validated based on clinical features and noninvasive test parameters in female patients with lower urinary tract symptoms. The model is a quick and easy-to-use tool to assess the risk of fBOO for urologists in their routine practice without an invasive UDS., (© 2024 International Federation of Gynecology and Obstetrics.)

Aims: Benign prostatic enlargement (BPE) can impact lower urinary tract function due to its potential progression to benign prostatic obstruction (BPO). Treatment options include removal of the obstruction by surgery or through use of therapeutics designed to slow growth or reduce tissue stress imposed by muscular stromal components. Inflammation and development of fibrosis can also raise intrinsic tissue stress within the gland, further impacting obstruction. Outflow tract obstruction can also impact emission and ejaculation if the obstruction persists., Methods: This review summarizes an ICI-RS think tank considering novel drug treatments that might address BPO caused by progressive development of BPE, as well as manage decompensation changes to bladder function., Results: Topics included recent advances in our understanding of pathological changes occurring to the prostate and other lower urinary tract tissues during progressive development of BPE, and how prevention or reversal might benefit from the identification of novel drug targets. These included contractile properties of prostatic tissues, the impact of BPE and its effects on bladder function, the deposition of intramural fibrotic tissue with protracted BPO, the role of inflammation in the development of BPE and its progression to BPO. In particular, we discussed current therapeutic options for treating BPE/BPO, and new therapeutic targets, what they treat and their advantage over current medications., Conclusion: Several new drug targets were identified, including soluble guanylate cyclase (sGC), the receptor for nitric oxide (NO•), and sGC activators that promotes sGC-mediated cGMP production when sGC is inactivated and unresponsive to NO•., (© 2023 Wiley Periodicals LLC.)

Aims: Lower urinary tract symptoms (LUTS) persist in up to 50% of patients after bladder outflow resistance reduction surgery (BORRS) in men. Our think tank aims to address the predictive factors for persistent LUTS after BORRS and to propose the recommendations for future research to enable improved better patient counseling and selection by more accurate prediction of treatment outcome., Methods: A think tank of ICI-RS gathered in 2023, Bristol, UK, to discuss the pre and postsurgical clinical and urodynamic evaluation of men undergoing BORRS and whether it is possible to predict which men will have persistent LUTS after BORRS., Results: Our think tank agrees that due to the multifactorial, and still not fully understood, etiology of male LUTS it is not possible to precisely predict in many men who will have persistent LUTS after BORRS. However, severe storage symptoms (overactive bladder, OAB) in association with low volume and high amplitude detrusor overactivity and low bladder capacity in preoperative urodynamics, increase the likelihood of persistent OAB/storage symptoms after BORRS. Furthermore, patients who are clearly obstructed and have good bladder contractility on preoperative pressure flow studies do better postoperatively compared to their counterparts. However, the benefit of pressure flow studies is decreased in patients who do not acceptably void during the study. Poor voiding after BORRS may occur due to persistent obstruction or detrusor underactivity., Conclusion: Future research is needed to increase our understanding of why male LUTS persist after surgery, and to enable better patient selection and more precise patient counseling before BORRS., (© 2024 Wiley Periodicals LLC.)

Aims: To address how invasive therapies for benign prostatic obstruction (BPO) have been evaluated, what their effect is on BPO, if they can prevent progression to BPO and how new therapies need to be evaluated before implementation into clinical practice., Methods: The think tank conducted a literature review and looked at the previous and current American Urological Association, European Association of Urology and the International Consultation on Urological Diseases guidelines to see what procedures have been used to treat BPO. They then assessed whether trials have been conducted before implementation of the procedures and whether they have been compared to a "gold" standard treatment. The use of urodynamics has also been addressed in the think tank in relation the clinical trials as well as terminology., Results: Guidelines vary in the use of terminology when it comes to BPO with some continuing to use the term benign prostatic hyperplasia (BPH). There are several procedures for example, TUNA, which have become obsolete although continues to be mentioned in the guidelines until recently. Majority of procedures have been introduced without comparing to "gold" standard treatment and without any long-term data. There continues to be many unknowns with regard to the success of some of the BPO procedures and why some of the adverse events develop., Conclusion: There needs to be more robust long-term clinical trials conducted of new BPO therapies, with men who have both lower urinary tract symptoms and urinary retention, before introduction into clinical practice., (© 2023 Wiley Periodicals LLC.)

Background: Diagnosing underlying causes of nonneurogenic male lower urinary tract symptoms associated with bladder outlet obstruction (BOO) is challenging. Video-urodynamic studies (VUDS) and pressure-flow studies (PFS) are both invasive diagnostic methods for BOO. VUDS can more precisely differentiate etiologies of male BOO, such as benign prostatic obstruction, primary bladder neck obstruction, and dysfunctional voiding, potentially outperforming PFS., Objective: These examinations' invasive nature highlights the need for developing noninvasive predictive models to facilitate BOO diagnosis and reduce the necessity for invasive procedures., Methods: We conducted a retrospective study with a cohort of men with medication-refractory, nonneurogenic lower urinary tract symptoms suspected of BOO who underwent VUDS from 2001 to 2022. In total, 2 BOO predictive models were developed-1 based on the International Continence Society's definition (International Continence Society-defined bladder outlet obstruction; ICS-BOO) and the other on video-urodynamic studies-diagnosed bladder outlet obstruction (VBOO). The patient cohort was randomly split into training and test sets for analysis. A total of 6 machine learning algorithms, including logistic regression, were used for model development. During model development, we first performed development validation using repeated 5-fold cross-validation on the training set and then test validation to assess the model's performance on an independent test set. Both models were implemented as paper-based nomograms and integrated into a web-based artificial intelligence prediction tool to aid clinical decision-making., Results: Among 307 patients, 26.7% (n=82) met the ICS-BOO criteria, while 82.1% (n=252) were diagnosed with VBOO. The ICS-BOO prediction model had a mean area under the receiver operating characteristic curve (AUC) of 0.74 (SD 0.09) and mean accuracy of 0.76 (SD 0.04) in development validation and AUC and accuracy of 0.86 and 0.77, respectively, in test validation. The VBOO prediction model yielded a mean AUC of 0.71 (SD 0.06) and mean accuracy of 0.77 (SD 0.06) internally, with AUC and accuracy of 0.72 and 0.76, respectively, externally. When both models' predictions are applied to the same patient, their combined insights can significantly enhance clinical decision-making and simplify the diagnostic pathway. By the dual-model prediction approach, if both models positively predict BOO, suggesting all cases actually resulted from medication-refractory primary bladder neck obstruction or benign prostatic obstruction, surgical intervention may be considered. Thus, VUDS might be unnecessary for 100 (32.6%) patients. Conversely, when ICS-BOO predictions are negative but VBOO predictions are positive, indicating varied etiology, VUDS rather than PFS is advised for precise diagnosis and guiding subsequent therapy, accurately identifying 51.1% (47/92) of patients for VUDS., Conclusions: The 2 machine learning models predicting ICS-BOO and VBOO, based on 6 noninvasive clinical parameters, demonstrate commendable discrimination performance. Using the dual-model prediction approach, when both models predict positively, VUDS may be avoided, assisting in male BOO diagnosis and reducing the need for such invasive procedures., (©Chung-You Tsai, Jing-Hui Tian, Chien-Cheng Lee, Hann-Chorng Kuo. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 23.07.2024.)

Purpose of Review: Surgical treatment of benign prostatic hyperplasia (BPH) carries a significant risk of ejaculation dysfunction. Preservation of antegrade ejaculation while providing effective, well tolerated, and durable treatment of BPH is a paramount component of physical and sexual well being for significant number of men. We reviewed available literature with an aim of providing status on antegrade ejaculation preserving BPH surgical therapies., Recent Findings: Minimally invasive surgical therapies for BPH have been developed over the last decade, with significant marketing emphasis on their potential for preservation of antegrade ejaculation. However, the question about durability of relief of bladder outlet obstruction remains. Parallel to this technological development, the understanding of anatomical structures involved in ejaculation have resulted in technical modifications of well established surgical treatments modalities like transurethral resection of prostate, endoscopic enucleation of prostate and simple prostatectomy, thereby providing safe and durable relief of bladder outlet obstruction secondary to BPH with a satisfactory preservation of antegrade ejaculation., Summary: Preservation of antegrade ejaculation is an important goal for significant number of men needing BPH surgery. Novel minimally invasive surgical technologies have been developed for this purpose; but understanding of the anatomical structures essential for antegrade ejaculation have allowed technical modification of existing surgical techniques with excellent preservation of antegrade ejaculation., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: To evaluate the effects of Prostate artery embolization (PAE) and open simple prostatectomy (OP) on lower urinary tract symptoms and urodynamic parameters in subjects with prostate size >80cc³., Methods: PoPAE study (OP or PAE) was a randomized, open-label controlled trial performed between January 2020 and May 2022. Subjects with large prostates (>80cc³), urodynamic parameters meeting obstruction criteria (Bladder Outlet Obstruction Index-BOOI>40), and good detrusor function (Bladder contractility index>100) were included. The primary and co-primary endpoints were the variation in peak flow rate on uroflowmetry (Qmax) and BOOI. The secondary endpoints were the IPSS and ultrasonographic changes., Results: Twenty three and 25 subjects underwent PAE and OP were evaluated, respectively. At baseline, the 2 groups have shown similar clinical, radiological, laboratory, and urodynamic parameters. After 6 months, Qmax improved 8,3 ± 4.17 mL/sec in PAE and 15.1 ± 8.04 mL/sec in OP (mean difference 6.78 in favor of PE; P = .012 [CI -9.00 to -3.00]). After treatment, 88% of those men underwent OP were classified as unobstructed or equivocal (BOOi<40). On the other hand, 70% of subjects underwent PAE remained obstructed (BOOI>40) and none of them shifted to unobstructed status (BOOI<20). It was observed a similar reduction in IPSS and PVR in both groups., Conclusion: PAE was inferior to conventional surgery for releasing BOO and improving peak urinary flow in large prostates. Nevertheless, PAE was able to improve symptoms and PVR, and might be an alternative method in selected patients., Competing Interests: Declaration of Competing Interest The authors declare to provide transparency on re-use of material and mention any unpublished material included in the manuscript., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: To assess long-term renal function and micturition pattern of males submitted to transurethral resection of the prostate (TURP) for moderate-to-severe lower urinary tract symptoms (LUTS) after renal transplantation (RT). To investigate the role of clinical and urodynamic (UD) parameters for bladder outlet obstruction (BOO) diagnosis in these patients., Methods: Retrospective data analysis of ≥ 50 years old patients who underwent RT between 01/2005 and 12/2016. Patients with moderate-to-severe LUTS after RT who underwent a urologic evaluation and a UD study were included. TURP was performed in case of BOO diagnosis. Kidney function and micturition patterns were evaluated before, 3, 12, 24, 36, and 48 months after TURP. Predictors of BOO were assessed at univariable and multivariable logistic regression models. Statistical analysis was performed with STATA16., Results: 233 male patients ≥ 50 years underwent RT. 71/233 (30%) patients developed voiding LUTS. 52/71 (73%) patients with moderate-to-severe LUTS underwent UD. TURP was performed in 36/52 (69%) patients, with BOO diagnosis. Median (interquartile range) follow-up was 108 (75-136) months. Maximum flow at flowmetry (Qmax), International Prostate Symptom Score and post-voided residual volume improved significantly after surgery. Serum creatinine decreased and glomerular filtration rate improved significantly at follow-up, especially when TURP was performed ≤ 6 months from RT. At the multivariable model, bladder capacity ≥ 300 mL (OR = 1.74, CI 95% 1.03-3.15, p = 0.043) and detrusor pressure at Qmax (OR = 2.05, CI 95% 1.48-3.02, p = 0.035) were the independent predictors of BOO., Conclusion: RT patients with moderate-to-severe LUTS at risk for BOO and graft failure are better identified by UD than clinical parameters. Bladder capacity and voiding pressure are key for the early diagnosis of BOO., (© 2021. The Author(s).)

Voiding dysfunction can result from detrusor underactivity (DU), bladder outlet obstruction (BOO), or both. Conceptually, women with high-pressure low-flow urodynamic profiles are diagnosed with BOO without DU. However, the possibility of BOO is often neglected in women with DU-like (low-pressure low-flow) urodynamic (UDS) profiles. By reviewing the videourodynamic studies (VUDS) of 1678 women, our study identified the key factors suggesting urodynamic BOO (determined by radiographic evidence of obstruction) in women with DU-like UDS profiles (Pdet.Qmax < 20 cmH2O and Qmax < 15 mL/s). In 355 women with DU-like UDS profiles, there were 70 (19.7%) with BOO and 285 (80.3%) without BOO. The BOO group had predominantly obstructive symptoms. The BOO group showed significantly decreased bladder sensation, lower detrusor pressure (Pdet.Qmax), lower flow rate (Qmax), smaller voided volume, and larger post-voiding residual (PVR) compared to the non-BOO group. In multivariate analysis, volume at first sensation, Qmax, PVR, and detrusor overactivity (DO) remained independent factors for BOO. The receiver operating characteristic (ROC) areas for the parameters were largest for PVR (area = 0.786) and Qmax (area = 0.742). The best cut-off points were 220 mL for PVR and 4 mL/s for Qmax. Our findings provide simple indicators for BOO in women with DU., (© 2021. The Author(s).)

Purpose: To determine the unique contributions from elevated voiding and storage pressures in the development of fibrosis and the epithelial-to-mesenchymal transition (EMT) in urothelial cells, and how progressive BOO pressure cycling is an important mechanical cue leading to these pathological changes., Materials and Methods: Urothelial cells isolated from control, SHAM, 2 (acute)- or 6 (chronic)-week BOO rats treated with an inflammasome inhibitor or no drug. Total RNA was isolated and RT-PCR was conducted with custom primers for pro-fibrotic and EMT genes. In separate experiments, a rat urothelial cell line was exposed to cyclic pressure regimes characteristic of acute and chronic BOO in the presence or absence of an inflammasome inhibitor. Following exposure, RT-PCR was conducted, collagen content was determined and intracellular caspase-1 activity was measured., Results: Urothelial cells isolated from acute and chronic BOO rat models demonstrated expression of pro-fibrotic and EMT genes. Similarly, MYP3 rat urothelial cells subjected to pressure cycling regimes that reflect intravesical pressures in the acute or chronic BOO bladder also demonstrated increased expression of pro-fibrotic and EMT genes, along with elevated soluble collagen. Treatment with inflammasome inhibitors reduced expression of pro-fibrotic genes in the rat model and pressure cycling model but had a limited effect on EMT., Conclusion: These results indicate that acute and chronic BOO pressure cycling are essential in the initiation and progression of fibrosis in the bladder via the NLRP3 inflammasome, but also provide new evidence that there is also an alternative NLRP3-independent pathway leading to EMT and fibrosis., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Objective: To evaluate the urodynamics (UDS) of patients with postural tachycardia syndrome (PoTS)., Methods: Patients with a confirmed diagnosis of PoTS referred by the department of neuro-cardiology to the neuro-urology were identified and their UDS were retrospectively reviewed., Results: In total, 50 patients (47 = 94.0% female) with confirmed PoTS and available UDS were identified. Mean age of females and males was 32.4 and 28.2 years, P = .15. Intermittent self-catheterisation was being used by 15/47 (31.9%) females at assessment. Detrusor overactivity was observed in 6 females (12.8%) (all at end fill and associated with urgency). In total, 14 (29.8%) females had no sensation of filling. No patients had an "unsafe" bladder. In total, 15/47 (31.9%) of women were unable to void with UDS catheters. Straining was reported in 22/35 (68.8%) of females. The female bladder outflow obstruction index = P Det Q max - 2.2(Q max ) was over 5 in 10/28 (35.7%) and over 18 in 5 (17.9%). The bladder contractility index = P Det Q max  + 5Q max was under 100 in 18/28 (28.6%) women., Conclusion: The UDS of patients with "PoTS bladder" often demonstrate a poorly sensate but stable and safe bladder with functional obstruction and impaired bladder contractility that may necessitate straining or intermittent self-catheterisation., (Crown Copyright © 2021. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess the correlation between post-void residual urine ratio (PVR-R) and pathological bladder emptying diagnosed by pressure-flow studies (PFS) in males with lower urinary tract symptoms (LUTS)., Materials and Methods: PVR-R and PVR urine were evaluated in 410 males underwent PFS for LUTS. PVR-R was the percentage of PVR to bladder volume (voided volume+PVR). Schafer and International Continence Society (ICS) nomograms, Bladder Contractility Index (BCI) were used to diagnose bladder outlet obstruction (BOO) and detrusor underactivity (DUA). We subdivided the cohort in 4 groups: Group I, BOO+/DUA+; Group II, BOO-/DUA+; Group III, BOO+/DUA-; Group IV, BOO-/DUA- (control group). We subdivided the 4 groups according to PVR-R strata: (1) 0%-20%; (2) 21%-40%; (3) 41%-60%; (4) 61%-80%; (5) 81%-100%., Results: Group I had a greater median PVR-R (50%) with a >40% in 61.4% of the cohort. Median PVR-R was 16.6% in Group II, 24% in Group III, and 0% in the control Group. According to ICS nomograms and BCI, median PVR-R and PVR were significantly higher (p<0.001) in obstructed and underactive males. PVR-R threshold of 20% allowed to recognize males with voiding disorders with high sensibility, specificity, PPV, and NPV. A PVR-R cut-off of 40% identified males with associated BOO and DUA and more severe voiding dysfunction., Conclusions: A higher PVR-R is related to a more severe pathological bladder emptying, and to the association of BOO and DUA. PVR-R may have a clinical role in first assessment of males with LUTS and severe voiding dysfunction., Competing Interests: The authors have nothing to disclose., (© The Korean Urological Association, 2021.)

Lower urinary tract symptoms (LUTS) in aging men are commonly attributed to bladder outlet obstruction from benign prostatic hyperplasia (BPH) but BPH/LUTS often reflects a confluence of many factors. We performed a hierarchical cluster analysis using four objective patient characteristics (age, HTN, DM, and BMI), and five pre-operative urodynamic variables (volume at first uninhibited detrusor contraction, number of uninhibited contractions, Bladder Outlet Obstruction Index (BOOI), Bladder Contractility Index (BCI) and Bladder Power at Qmax) to identify meaningful subgroups within a cohort of 94 men undergoing surgery for BPH/LUTS. Two meaningful subgroups (clusters) were identified. Significant differences between the two clusters included Prostate Volume (95 vs 53 cc; p-value = 0.001), BOOI (mean 70 vs 49; p-value = 0.001), BCI (mean 129 vs 83; p-value <0.001), Power (689 vs 236; p-value <0.001), Qmax (8.3 vs 4.9 cc/sec; p-value <0.001) and post-void residual (106 vs 250 cc; p-value = 0.001). One cluster is distinguished by larger prostate volume, greater outlet resistance and better bladder contractility. The other is distinguished by smaller prostate volume, lower outlet resistance and worse bladder contractility. Remarkably, the second cluster exhibited greater impairment of urine flow and bladder emptying. Surgery improved flow and emptying for patients in both clusters. These findings reveal important roles for both outlet obstruction and diminished detrusor function in development of diminished urine flow and impaired bladder emptying in patients with BPH/LUTS., Competing Interests: The authors have declared that no competing interests exist.

Alteration of bladder morphology and function was the most important consequence of bladder outlet obstruction (BOO). Using a rat model of partial BOO (pBOO), we found that rats treated with metformin showed lower baseline pressures with a reduced inflammatory reaction in the early phase (2 wk) after pBOO. The NLR family pyrin domain containing 3 inflammasome pathway was inhibited in pBOO rat bladders with treatment of metformin in the early phase. Metformin reduced the activity of NLR family pyrin domain containing 3 in primary urothelial cells. In the chronic phase (9 wk after pBOO), metformin treatment ameliorated bladder fibrosis and improved the reduced compliance. Treatment with metformin suppressed the activation of Smad3 and compensated the diminished autophagy in 9-wk pBOO rat bladders. Autophagy was inhibited with upregulation of profibrotic proteins in primary fibroblasts from chronic pBOO bladders, which could be restored by administration of metformin. The antifibrotic effects of metformin on fibroblasts were diminished after silencing of AMP-activated protein kinase or light chain 3B. In summary, this study elucidates that oral administration of metformin relieves inflammation in the bladder during the early phase of pBOO. Long-term oral administration of metformin can prevent functional and histological changes in the pBOO rat bladder. The current study suggests that metformin might be used to prevent the development of bladder dysfunction secondary to BOO. NEW & NOTEWORTHY The present study in a rat model showed that oral administration of metformin alleviated inflammation following partial bladder outlet obstruction in the early phase and ameliorated bladder fibrosis as well as bladder dysfunction by long-term treatment. Our study indicated that metformin is a potential drug to inhibit bladder remodeling and alleviate bladder dysfunction. Clinical trials are needed to validate the effect of metformin on the bladder dysfunction and bladder fibrosis in the future.

Purpose: To establish the correlation between flow rate curve shape and video-urodynamic findings in women with lower urinary tract symptoms (LUTS)., Methods: A retrospective review of consecutive women with LUTS who performed a free flow study immediately before undergoing video-urodynamic investigations over a 28-month period. Flow rate curve shape and video-urodynamic parameters were analysed. Free flow curves were defined into five categories: bell-shaped, prolonged, fluctuating, intermittent or plateau. Women who voided less than 150 ml on the free flow study were excluded from the analysis., Results: A total of 250 women with LUTS, with a mean age 48 years (range 18-83), were included. Bell-shaped tracings excluded obstruction in 89%. Prolonged flow rate curves diagnosed obstruction in 62% and detrusor underactivity in 8%. Fluctuating and intermittent flow rate curves were associated with urodynamic obstruction in 37 and 39%, respectively, and detrusor underactivity in 25 and 29%, respectively. A plateau flow rate curve was indicative of urodynamic obstruction in all three cases observed., Conclusion: Flow rate curve patterns can be suggestive of urodynamic diagnoses. Women without a prolonged void and bell-shaped traces had normal voiding urodynamics in 76% of cases, and the majority could be managed without invasive investigations. Patients with fluctuating and intermittent flow rate curves demonstrate a spectrum of urodynamic diagnoses with a third of cases having obstruction and a third of cases having detrusor underactivity. Plateau flow rate curve patterns are associated with urethral obstruction.

Objective: To present the clinical and radiological characteristics of women with severe structural deterioration of the bladder and upper urinary tract secondary to Primary Bladder Neck Obstruction (PBNO), and their outcomes after bladder neck incision (BNI)., Methods: Retrospective evaluation of adult women who underwent BNI for PBNO at one institution. Patients were assessed for symptoms, renal function, structural abnormalities of the urinary tract and video-urodynamics. PBNO diagnosis was confirmed with video-urodynamics in all patients. BNI was performed at the 4-5 and/or 7-8 o'clock positions. Postoperative symptoms, PVR, uroflowmetry and renal function were evaluated and compared to baseline., Results: Median patient age was 56.5 years (range 40-80). All presented with urinary retention-four were on clean intermittent Catheterization (CIC) and two with a Foley catheter. All patients had bladder wall thickening and diverticula. Four women had elevated creatinine levels, bilateral hydronephrosis was present in five (83.3%). After BNI, all patients resumed spontaneous voiding without the need for CIC. Median Qmax significantly improved from 2.0 [1.0-4.0] mL/s to 15 [10-22.7] mL/s (p = 0.031). Median PVR decreased from 150 to 46 [22-76] mL (p = 0.031). There were no postoperative complications. Creatinine levels returned to normal in 3/4 (75%) patients., Conclusion: PBNO in women may result in severe damage to the bladder and upper urinary tract. Despite severe structural abnormalities of the bladder, BNI was effective in reducing symptoms and improving structural and functional abnormalities of the lower and upper urinary tract., Competing Interests: The authors have declared that no competing interests exist.

Background: Lower urinary tract symptoms are one of the most common groups of non-movement symptoms in patients with Parkinson's disease (PD). Storage symptoms are well-acknowledged, but neurogenic voiding dysfunction caused by PD remains a knowledge gap. This study aimed to evaluate the neurogenic bladder outlet obstruction in male patients with PD and its clinical significance., Methods: Male patients who were diagnosed with PD and underwent urodynamic studies were retrospectively reviewed. The patients with prostate size < 30 ml and bladder outlet obstruction index ≥40 were included in the study. Lower urinary tract symptoms were evaluated by International Prostate Symptom Score (IPSS). Free flowmetry was performed and post void residual (PVR) volume was measured by ultrasound at follow-up., Results: Six patients were included in the final analysis. The mean age was 68.2 and the mean movement symptom duration was 70.7 months. The patients had a mean IPSS of 12.5 and mean PVR volume of 70.8 ml. All patients had slow stream but none of them reported significant voiding difficulty. Urodynamic studies showed the delayed urinary sphincter relaxation and the special trace pattern. After a mean follow-up of 20 months, they had a mean IPSS of 12.5 and mean PVR volume of 73.3 ml. None of them complained of significant voiding difficulty at follow-up., Conclusion: The delayed urinary sphincter relaxation is a rare but repeatable phenomenon in male patients with PD. It is unlikely to cause disturbing voiding dysfunction, as reported by the patients, and does not progress prominently during the course of PD. Further studies are needed to investigate the nature of this special type of neurogenic BOO and whether it is peculiar to PD in a larger patient cohort.

Objectives: Both detrusor underactivity (DU) and bladder outlet obstruction are the common causes of chronic urinary retention. Some novel treatment approaches focus on modulating micturition reflex and external urethral sphincter (EUS) function. This study used electrophysiologic (EP) studies to investigate the micturition reflex and EUS conditions of chronic urinary retention patients., Methods: Sixty patients with urodynamic DU and chronic urinary retention were studied using (1) bulbocavernous reflex (BCR) by electric stimulation, (2) electromyography (EMG) of the EUS, and (3) nerve conduction velocity (NCV) studies of the pudendal nerve. The EP findings were analyzed in DU patients with different etiologies., Results: The BCR was positive in 41.7% of patients. In EMG studies, denervation, reinnervation, and reduced recruitment of the EUS were observed in 21.7%, 71.7%, and 88.3% patients, respectively. Decreased amplitude of pudendal nerve conduction in NCV studies was noted in 73.3% of patients. Patients with sacral neuropathy had a lower BCR positive rate (p = 0.001), a nonsignificant but higher denervation rate (p = 0.059) in EMG studies, and a higher rate of decreased amplitude in NCV (p = 0.011) than those without sacral neuropathy. Excluding patients with sacral neuropathy or diabetes mellitus, a high percentage of neurologic deficits was still detected in EP studies., Conclusions: Chronic urinary retention patients with urodynamic DU not only have bladder dysfunction, but also potential neuropathy in the sacral reflexes, pudendal nerve, or urethral sphincter innervation. The neurologic deficits explored in EP studies may affect the decision-making around the therapy to restore the voiding function in DU., (© 2021 Wiley Periodicals LLC.)

Objectives: To assess if a standard hydration protocol will achieve voided volumes over 150 mL and more reliable uroflowmetry results., Methods: This is a single-blinded crossover study of 40 patients with benign prostatic obstruction and 34 healthy volunteers. Subjects were enrolled prospectively between January and March 2019. All subjects performed two randomly ordered uroflowmetry tests. One test was performed when subjects sensed their bladder was full and had the urge to void and another one after emptying the bladder and ingesting 1.5 L of water within 1 hour (prehydration). Uroflowmetry parameters were compared between the benign prostatic obstruction group and the healthy volunteers. Uroflowmetry results were categorized as reliable, residual, and suboptimal with respect to voided volumes. This study has been registered in the UMIN Clinical Trials Registry (UMIN000035446)., Results: The benign prostatic obstruction group and the healthy volunteer group presented no difference in respect of uroflowmetry test reliability (P = .459). Uroflowmetry results were reliable in 58 (78.4%) subjects in the prehydrated group and was reliable in 30 (40.5%) subjects in the non-prehydrated group. The difference was statistically significant (P < .05). In the benign prostatic obstruction group and healthy volunteer group, the rate of reliable uroflowmetry tests was significantly higher with prehydration (P < .05). The comparative analysis of uroflowmetry parameters between tests performed with and without prehydration revealed higher values in the prehydrated group (voided volume, maximum flow rate, average flow rate, and postvoiding residual volume; P < .05)., Conclusion: Prehydration of patients with 1.5 L of water within 1 hour before uroflowmetry improves uroflowmetry outcomes. By this hydration protocol, the chance to obtain a voided volume over 150 mL is increased significantly., (© 2020 John Wiley & Sons Australia, Ltd.)

Purpose: The UroCuff® Test is a noninvasive pressure flow study used to manage men with lower urinary tract symptoms. UroCuff Tests were performed on men with lower urinary tract symptoms to evaluate voiding characteristics and quantify changes in urodynamic parameters with age., Materials and Methods: This cross-sectional study included all UroCuff Tests performed at 103 urology practices in the U.S. Tests were de-identified prior to collection and analysis. Inclusion criteria required initial pressure flow study with subsequent tests excluded, voided volume 50 ml or greater, at least 1 cuff inflation and patient age greater than 20 years. Pressure, maximum flow rate, flow rate efficiency (maximum flow rate/Pcuff), voided volume and post-void residual were plotted by age and stratified by Newcastle Noninvasive Nomogram category., Results: A total of 50,680 patients 20 to 100 years old (median age 66.0) met inclusion criteria. Median Pcuff was 144.3 cmH 2 O and 60.8% of patients were categorized in the obstructed or high pressure/high flow Newcastle Noninvasive Nomogram quadrants. Median maximum flow rate was 10.9 ml per second and 55.8% had maximum flow rate greater than 10 ml per second. Median voided volume and post-void residual were 219.0 and 75.0 ml, respectively. All measures deteriorated with age (p <0.0001). Pcuff reflects the compensated/decompensated bladder function lifecycle. Values initially increased and reached peak pressure at age 62, then decreased by approximately 0.96 cmH 2 O per year until age 90., Conclusions: This study demonstrates that symptomatic patients enter urological practices at different urodynamic stages of bladder function and outlet obstruction, that Pcuff, maximum flow rate, voided volume, flow rate efficiency and post-void residual deteriorate with age, and that UroCuff is a sensitive evaluation of bladder performance.

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 H 2 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., (© 2020 Wiley Periodicals LLC.)

Objective: The present study was aimed to investigate (1) whether urodynamic factors are responsible for kidney damage in patients with bladder outlet obstruction (BOO) and (2) whether transurethral prostate surgery for BOO can alleviate the damage to the kidneys., Methods: This prospective observational study involved men aged 50-80 years. Prostate size and urodynamic test were performed during screening period. Laboratory tests to measure the glomerular filtration rate, the urinary protein to creatinine ratio and dipstick urinalysis were performed before and 6 months after the transurethral prostate surgery., Results: Sixty-seven patients completed the laboratory study among a hundred enrolled patients with urodynamically proven BOO. Among the urodynamic parameters, only low bladder compliance (lower than 60 mL/cmH 2 O) was associated with clinically significant proteinuria (p < 0.001). Transurethral prostate surgery significantly improved proteinuria (p = 0.007), especially in patients with low bladder compliance (p = 0.004), and subsequently decreased the risk grade of CKD progression (p < 0.001)., Conclusions: Low bladder compliance in patients with BOO may be a risk factor for kidney damage. Transurethral prostate surgery to relieve BOO could be a preventive method against CKD progression in patients with low bladder compliance.

Background: Currently, the diagnostic ability of uroflowmetry, the most widely used urodynamic test available for initial assessment of patients with lower urinary tract symptoms (LUTS), is considered limited by its inability to accurately discriminate between the underlying mechanisms of this condition. To improve the diagnostic accuracy of uroflow, we developed a mathematical formula that calculates the flow resistive forces index (QRF), a novel measure of bladder outflow/urethral resistance, and assessed its clinical applicability compared to the maximum flow rate (Q max )., Materials and Methods: A cross-sectional observational study was conducted in a cohort of 61 adult men presenting with voiding dysfunction symptoms, who all underwent free uroflowmetry followed by pressure flow study. The development of the mathematical formula which contains five key uroflowmetry variables (voided volume, flow time, Q max , average flow rate, and peak flow time) was based on the assumption that urine volume momentum changes during voiding, the concept of diphasic uroflow pattern (acceleration/deceleration), and the urethral resistance factor (URA) equation. Study subjects were classified either as obstructed or nonobstructed according to established urodynamic criteria (linearized passive urethral resistance relation, LinPURR; Abrams-Griffiths number, AGN [also called bladder outlet obstruction index, BOOI]; and URA). Univariate linear correlations, binary logistic regression model, and receiver operating characteristic (ROC) curve statistical analysis were employed (SPSS-22, MedCalc, GraphPad [P < .05])., Results: Outflow obstruction was diagnosed in 50.8% (1 in 2) patients. Univariate analysis, and bivariate linear correlation, binary logistic regression, and ROC curve analyses showed that the QRF was a strong independent predictor of bladder outlet/outflow obstruction (BOO), significantly outperforming Q max ., Conclusions: QRF index accurately predicts BOO, significantly outperforming the currently widely used bladder outlet obstruction estimator Q max . Despite potential study limitations (mainly small cohort size and lack of control group), we anticipate that with further study and proper clinical validation, QRF could become a valuable complement to uroflowmetry., (© 2020 John Wiley & Sons Australia, Ltd.)

Objective: To investigate bladder neck dysfunction (BND) in women with voiding dysfunction by video-urodynamic study (VUDS) and to examine the therapeutic results of different BND subtypes., Materials and Methods: We retrospectively reviewed consecutive women who had undergone VUDS for investigation of voiding dysfunction at our institution. The diagnosis of BND was made based on a nonfunneling bladder neck with or without high voiding detrusor pressure. Patients diagnosed as BND were retrieved, and the urodynamic parameters were compared with patients with dysfunctional voiding (DV) and other bladder outlet obstructions (BOO)., Results: Among 810 women with bladder outlet dysfunction, BND was noted in 100 (12.3%), poor pelvic floor relaxation in 336 (41.5%), DV in 325 (40.1%), cystocele in 19 (2%), and urethral stricture in 30 (4%). Compared with the normal tracing group, BND patients had a significantly smaller volume of bladder filling sensation (included first sensation of filling, full sensation and cystometric bladder capaicity) and a greater BOO index (BOOI) (all P < .05). Detrusor overactivity was noted in 46 (46%) BND patients. These urodynamic parameters in BND were not significantly different from patients with DV or other BOO. High-pressure BND had a greater BOOI, but low-pressure BND had a lower voiding efficiency. Both alpha-blocker therapy and transurethral incision of the bladder neck improved uroflow parameters in BND patients., Conclusions: BND includes 12.3% of women with bladder outlet dysfunction. High-pressure BND can cause anatomical BOO, whereas low-pressure BND is likely to affect micturition through inhibiting detrusor contractility. VUDS is the mainstay diagnostic tool to diagnose BND in women., (© 2020 John Wiley & Sons Australia, Ltd.)

Rationale: Voiding difficulty is more common in males, although it is not uncommon in females. Female voiding difficulty can be caused by iatrogenic, anatomic, and neurogenic factors, and specifically urethra stricture, impaired detrusor contractility, primary bladder neck obstruction, and detrusor-external sphincter dyssynergia. Labial adhesion is a rare cause of female voiding difficulty.The incidence of labial fusion has been reported to be 0.6% to 1.4% in children; however, the incidence in the elderly has yet to be fully elucidated., Patient Concerns: We present the case of a postmenopausal and sexually inactive 76-year-old female patient who had nearly total vaginal and urethral occlusion due to labial adhesion. She had no underlying diseases and came to our clinic with a 10-month history of voiding difficulty, postmicturition dribbling, and involuntary urinary leakage when getting up., Diagnosis: A genital examination revealed nearly total fusion of the labia minor with only a 3-mm pinhole opening at the posterior end., Interventions: Treatment included surgical separation, the local application of estrogen cream, and self-dilatation. She also received an antimuscarinic agent to treat overactive bladder secondary to bladder outlet obstruction which was caused by labial adhesion., Outcomes: No surgical complications occurred. Moreover, no labial adhesion or voiding dysfunction was found immediately after the surgery or after 6 months of follow-up., Lessons Subsections: Genital examinations are a basic but very important noninvasive skill for physicians. This case report highlights that genital examinations should be a priority for patients with gynecological or urological symptoms.

Aim: Bladder outflow in women (bladder outlet obstruction [BOO]) has no well-accepted defining diagnostic criteria. Various nomograms exist based on flow rates, pressure-flow data, and fluoroscopy. We have prospectively evaluated the Solomon-Greenwell bladder outflow obstruction nomogram (SG BOO nomogram) as a measurement of BOO resolution following targeted surgical intervention., Methods: The routine posttreatment urodynamics of 21 unselected women with an original urodynamic diagnosis of BOO on fluoroscopy and the SG BOO nomogram (BOO boundary defined as Qmax > 2.2 Pdet.Qmax + 5) were reviewed. All women had symptomatic BOO secondary to anterior pelvic organ prolapse (aPOP), urethrovaginal fistula (UVF), previous stress urinary incontinence (SUI) surgery, urethral stricture (US), or urethral diverticulum (U Div). Following treatment, all presenting symptoms resolved and simple urodynamics were performed as part of routine follow-up., Results: The urodynamic findings preoperatively and postoperatively showed statistically significant changes posttreatment in mean flow rate which increased from 9.38 to 14.71 mL/s, mean Pdet.Qmax which decreased from 38 to 18.38 cmH 2 O, and mean SG BOO nomogram probability (PBOO) which reduced from PBOO = 0.68 to 0.08. Mean SG BOO nomogram PBOO was significantly reduced posttreatment in all individual categories except UVF where a nonsignificant reduction from PBOO = 0.55 to 0.05 occurred., Conclusions: All urodynamic parameters significantly improve in women who become asymptomatic following surgical treatment of BOO. This improvement is best demonstrated by the change in probability of BOO according to the Solomon-Greenwell nomogram. These findings underline the validity of the Solomon-Greenwell female BOO nomogram for diagnosing and monitoring BOO in women., (© 2020 Wiley Periodicals, Inc.)

Aims: There have been few reports on whether long-term oral phosphodiesterase 5 inhibitor administration can ameliorate bladder changes due to bladder outlet obstruction (BOO). Therefore, we clarified the chronological changes of the bladder using male BOO rats and evaluated the effects of tadalafil on these changes., Methods: Eight-week-old male Sprague-Dawley rats were used. BOO was created by placing a polyethylene catheter around the urethra. Then, the rats were orally treated with a vehicle, or tadalafil 2 or 10 mg/kg until each evaluation period. Cystometric measurements were performed and the degree of fibrosis in the smooth muscle layer was evaluated at 2, 4, and 16 weeks., Results: In BOO rats, a significant increase in the number of non-voiding contractions (NVCs) and a shortened intercontraction interval (ICI) were observed in the earlier phase (2 and 4 weeks) compared to Sham rats. In the chronic phase (16 weeks), markedly increased residual urine volume and an extended ICI were observed accompanied by enhanced smooth muscle fibrosis. These results indicated that the bladder in BOO rats represented the overactive phenotype in the earlier phase and changed into the underactive phenotype in the chronic phase. Even in Sham rats, an increased number of NVCs and enhanced fibrosis were observed with time. Tadalafil administration significantly prevented these bladder changes in both BOO and Sham rats., Conclusions: Long-term oral administration of tadalafil can prevent functional and histological changes in the BOO rat bladder. This agent is also effective for the bladder functional change even in non-obstructed rats., (© 2020 Wiley Periodicals LLC.)

Aim: The International Continence Society (ICS) has standardized quality control and interpretation of uroflowmetry and urodynamics. We evaluated traces from two large studies of male lower urinary tract symptoms (UPSTREAM and UNBLOCS) against ICS standards of urodynamic equipment and practice., Methods: Ten percent of uroflowmetry and urodynamics traces were selected at random from hospital sites. A data capture template was designed from the ICS Fundamentals of Urodynamic Practice checklist. Two pretrained blinded assessors extracted the data, with a third assessor to arbitrate. Departmental records of calibration checks and equipment maintenance were scrutinized., Results: Seven out of twenty-five (28%) departments reported no calibration checks. Four sites (16%) could not provide annual service records. In 32 out of 296 (10.8%) uroflowmetry traces, findings were affected by artifact. One hundred ten urodynamic study traces were reviewed; in 11 records (10%), key pressure traces were incompletely displayed. In 30 (27.2%), reference zero was not set to atmospheric pressure. Resting pressures were outside the expected range for 36 (32.7%). Pressure drift was seen in 18 traces (16.4%). At pressure-flow study commencement, permission to void was omitted in 15 (13.6%). Cough testing after voiding was done in 71.2%, but the resulting cough spikes were significantly different in 16.5%. Erroneous diagnosis of bladder outlet obstruction (BOO) was identified in six cases (5.5%)., Conclusions: Erroneous diagnosis of BOO is a serious error of interpretation, as it could lead to unnecessary surgery. Other errors of standardization, testing, and interpretation were identified with lower risk of adverse implications. Inconsistent documentation of service records mean equipment accuracy is uncertain., (© 2020 The Authors. Neurourology and Urodynamics published by Wiley Periodicals LLC.)

We tested whether or not altered Ca 2+ spark activity accounted for detrusor overactivity (DO) of Wistar rats after partial bladder outlet obstruction (PBOO). We constructed a DO model through PBOO and studied the Ca 2+ spark activity of detrusor. By way of using confocal microscopy and the patch-clamp technique, Ca 2+ sparks and spontaneous transient outward currents (STOCs) in detrusor myocytes were measured respectively. Our results indicated that Ca 2+ spark activity and STOCs were significantly reduced in the DO detrusor myocytes compared to unafflicted control cells, and both of these had levels that were remarkably increased by applications of caffeine (10 μM), a RyR agonist, in DO myocytes. In addition, measures of detrusor contractions were also recorded by using freshly isolated detrusor strips. These results indicated that the spontaneous contraction of DO detrusor was significantly enhanced, and that the effect of caffeine (10 μM) upon detrusor contractions was reversed by applications of iberiotoxin (100 nM) which is a BK channel blocker. Western blotting (WB) analyses indicated that the levels of expression of ryanodine receptor type 2 (RyR2) and FK506 binding protein 12.6 (FKBP12.6) in bladder muscle were respectively decreased and increased in the samples from DO rats. Thus, we considered in the rat DO model wherein PBOO, the reduced Ca 2+ spark activity in detrusor myocytes partly contributed to overactive detrusor contractions. The impaired Ca 2+ spark activity may have resulted from decreased RyR2 expression and increased FKBP12.6 expression. Such novel findings in our research might help to provide means for better treatment outcomes for patients afflicted by bladder dysfunction.

Purpose: To identify urodynamic factors associated with the mechanical stop test and immediate spontaneous voiding following transurethral resection of prostate (TURP)., Methods: We identified 90 men who underwent TURP over a 12-month period. Forty-three (mean age 68 years) underwent urodynamic evaluation prior to TURP. Isovolumetric detrusor contractile pressure (P iso ) was obtained using the mechanical stop test during the voiding phase, and used to calculate detrusor contractile reserve (P res  = P iso - P det @Q max ). Primary outcome was spontaneous voiding after TURP., Results: Preoperative catheter-free spontaneous voiding was present in 63% of men (27/43) with a urodynamic (mean ± SD): Q max 6.2 ± 2.7 mL/s, P det @Q max 102 ± 47 cmH 2 O, P iso 124 ± 49 cmH 2 O, P res 22 ± 16 cmH 2 O, bladder outlet obstruction index (BOOI) 90 ± 49, and bladder contractility index (BCI) 132 ± 44. The remaining 16 catheter-dependent men demonstrated a urodynamic (mean ± SD): Q max 3.6 ± 3.3 mL/s, P det @Q max 87 ± 38 cmH 2 O, P iso 99 ± 51 cmH 2 O, P res 10 ± 18 cmH 2 O, BOOI 82 ± 36, and BCI 106 ± 48. Following TURP, 67% of men voided spontaneously with their first void trial, and in receiver operator analysis of urodynamic measures (P det @Q max , P iso , P res , BOOI and BCI), only P res was significantly associated with immediate spontaneous voiding after TURP (threshold P res  ≥ 9 cmH 2 O, AUC = 0.681, p = 0.035)., Conclusions: In men who underwent TURP, a P res  ≥ 9 cmH 2 O was associated with immediate spontaneous voiding and may be easily incorporated into the postoperative pathway.

The objective of this study was to investigate the role of ATP in cholinergic neurotransmission in the urinary bladder of control men and of patients obstructed as a result of benign prostatic hyperplasia (BPH). Human detrusor samples were collected from 41 patients who submitted to transvesical prostatectomy resulting from BPH and 26 male organ donors. The release of [ 3 H]acetylcholine ([ 3 H]ACh) was evoked by electrical field stimulation (10 Hz, 200 pulses) in urothelium-denuded detrusor strips. Myographic recordings were performed to test detrusor strip sensitivity to ACh and ATP. Nerve-evoked [ 3 H]ACh release was 1.5-fold higher in detrusor strips from BPH patients compared with controls. This difference was abolished after desensitization of ionotropic P2X1-3 receptors with an ATP analog, α , β -methylene ATP (30 μ M, applied for 15 minutes). TNP-ATP (10 nM, a preferential P2X2/3 antagonist) and A317491 (100 nM, a selective P2X3 antagonist) were about equipotent in decreasing nerve-evoked [ 3 H]ACh release in control detrusor strips, but the selective P2X1 receptor antagonist NF023 (3 μ M) was devoid of effect. The inhibitory effect of TNP-ATP (10 nM) increased from 27% ± 9% to 43% ± 6% in detrusor strips of BPH patients, but the effect of A317491 (100 nM) [ 3 H]ACh release unaltered (20% ± 2% vs. 24% ± 4%). The amplitude of ACh (0.1-100 μ M)-induced myographic recordings decreased, whereas sensitivity to ATP (0.01-3 mM) increased in detrusor strips from BPH patients. Besides the well characterized P2X1 receptor-mediated contractile activity of ATP in pathologic human bladders, we show here for the first time that cholinergic hyperactivity in the detrusor of BPH patients is facilitated by activation of ATP-sensitive P2X2/3 heterotrimers. SIGNIFICANCE STATEMENT: Bladder outlet obstruction often leads to detrusor overactivity and reduced bladder compliance in parallel to atropine-resistant increased purinergic tone. Our data show that P2X1 purinoceptors are overexpressed in the detrusor of patients with benign prostatic hyperplasia. Besides the P2X1 receptor-mediated detrusor contractions, ATP favors nerve-evoked acetylcholine release via the activation of prejunctional P2X2/3 excitatory receptors in these patients Thus, our hypothesis is that manipulation of the purinergic tone may be therapeutically useful to counteract cholinergic overstimulation in obstructed patients., (Copyright © 2019 by The American Society for Pharmacology and Experimental Therapeutics.)

To analyze the change of detrusor contractility by investigating urodynamic characteristics with long term follow-up. This study retrospectively reviewed 166 lower urinary tract symptoms patients without bladder outlet obstruction (BOO) and 63 patients with BOO who underwent repeated urodynamic studies at the first time and more than 10 years later. The urodynamic parameters, bladder contractility index (BCI), and BOO index (BOOI) were compared before and after. As time goes by, detrusor pressure at maximum flow rate (PdetQmax) significantly decreased and post-void residual (PVR) volume significantly increased in both men and women. Full sensation, urge sensation, voided volume, and BCI significantly decreased. We also compared men with and without BOO, PdetQmax, maximum flow rate (Qmax), voided volume, and BCI all significantly decreased in both groups without difference. PVR increased greater in men with BOO after >10 years significantly (p = 0.036). Women with detrusor overactivity (DO) under antimuscarinic showed no significant BCI change compared to patients without DO (p = 0.228). Detrusor contractility decreases in men and women after >10 years of follow-up. However, this finding suggests that patients with BOO or DO under adequate medical treatment, detrusor contractility is not aggravated over 10 or more years of follow-up.

Studies on bladder dysfunction (BD), more specifically functional-urodynamic changes in the bladder as a result of bladder outlet obstruction (BOO) have been summarized for this TT. Based on available, but limited evidence from human studies a three-stage model can be hypothesized to characterize BOO-induced bladder remodeling: hypertrophy, compensation (increased detrusor contractility during the voiding phase, often in combination with filling phase detrusor overactivity) followed by the phase of decompensation [detrusor underactivity]. The time between the start of compensation and eventual decompensation seems to be determined by age of onset, severity, and type of obstruction and clinical mitigating factors such as vascular and metabolic problems. Understanding the relative contributions of these factors may allow the development of personalized timelines and probabilities for these obstructed patients., (© 2019 The Authors. Neurourology and Urodynamics Published by Wiley Periodicals, Inc.)

Aims: Efforts to engineer and repair genitourinary tissue to treat lower urinary tract dysfunction (LUTD) have recently increased thanks in part to advances in stem cell (SC) research. At the International Consultation on Incontinence-Research Society meeting in Bristol in 2018 a proposal was convened to address the question: has the potential of SCs in treating LUTD reached clinical maturity?, Methods: The proposal conducted a literature review and an expert consensus meeting focusing on available data from animal models and clinical trials involving the use of SCs for LUTD., Results: To date, there are only small studies investigating bladder replacement using scaffolds with or without SC. Results have been conflicting because of the variability in cell numbers, biomaterials types, and graft surface differences. Similarly, preclinical results suggest a possible role of SC in bladder outlet obstruction (BOO); however, SC clinical trials for BOO are lacking. Research into the use of SC for female stress urinary incontinence (SUI) is close to reaching clinical maturity. In the Canadian phase 3 randomized controlled trial (RCT), a beneficial effect of adult muscle-derived cells (AMDC) over placebo was detected in reducing the frequency of incontinence episodes, especially after prior anti-incontinence surgery. Only two small studies have been published on male SUI., Conclusions: Questions remain regarding the mechanism of action of SC injected into the LUT and the viability of cells seeded onto grafts placed into the LUT. Also, the optimal time for intervention with SC therapy in the LUT remains to be elucidated., (© 2019 Wiley Periodicals, Inc.)

Purpose: To evaluate the presence of intravesical prostatic protrusion (IPP) and its thickness-to-height (T/H) ratio as a predictor for the clinical outcome and morbidity of prostatic artery embolization (PAE) for benign prostatic hyperplasia., Materials and Methods: This was a prospective, single-center, institutional review board-approved study from June 2015 to December 2018 of 82 consecutive patients (age, 53-79 years; median, 66 years) with International Prostate Symptom Score (IPSS) ≥15 and quality-of-life (QOL) score ≥3. The presence of IPP and its T/H ratio were assessed on baseline magnetic resonance imaging for their correlation with the clinical outcomes of suboptimal IPSS (IPSS ≥10) and suboptimal QOL (QOL ≥3) up to 12 months after PAE and the occurrence of post-procedure complications (≤30 days), which caused a certain degree of urinary outflow obstruction. The chi-squared test was used for analysis., Results: IPP was present in 57 of 82 patients (69.5%). The presence of IPP correlated with the occurrence of post-procedure complications (P = .009) but not with suboptimal IPSS at 12 months (P = .758). IPP with a T/H ratio ≤1.3 correlated with suboptimal IPSS at 12 months (P = .025) and suboptimal QOL at 6 months (P = .025) and 12 months (P = .008), as well as with the occurrence of post-procedure complications (P = .009)., Conclusions: IPP with a T/H ratio ≤1.3 predicted the occurrence of post-procedure complications with urinary obstruction. A T/H ratio ≤1.3 but not the presence of IPP alone predicted the clinical outcome up to 12 months after PAE., (Copyright © 2019 SIR. Published by Elsevier Inc. All rights reserved.)

Aims: Ligation of the urethra to create partial bladder outlet obstruction has widely been used as an animal model of bladder obstruction, although obstructive bladder dysfunction may be due to both mechanical and functional obstruction. Previous studies in rodents have demonstrated that long-term nitric oxide (NO) deficiency can lead to detrusor overactivity, and lack of NO may thus cause impairment of bladder outlet relaxation. The aim of this study was to define the characteristics of bladder and urethral dysfunction induced by chronic NO deficiency through both in vivo and in vitro investigations., Main Methods: Rats were divided into two groups, and one group received an NO synthase inhibitor (N ω -nitro-L-arginine methyl ester hydrochloride: L-NAME) in the drinking water for 4 weeks. Bladder and urethral function were evaluated by continuous cystometry and isovolumetric cystometry. In vitro functional studies of detrusor strips and measurement of the mRNA and protein expression of an ischemic marker and a gap junction protein were also performed in separate rats., Key Findings: L-NAME administration raised blood pressure and decreased plasma nitrite/nitrate level compared to the control group. L-NAME treatment increased the frequency of bladder contractions and the residual volume, and elevated urethral pressure and bladder contraction pressure. In addition, carbachol-induced contraction was reduced in isolated detrusor strips from the L-NAME group, and bladder expression of HIF-1 and connexin 43 showed upregulation., Significance: These findings suggest that chronic administration of L-NAME to rats induces bladder hyperactivity with residual urine, and may provide a useful model of functional bladder obstruction., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objectives: To elucidate the mechanism of action of the α 1 -blocker, naftopidil, in partial bladder outlet obstruction animals, by studying non-voiding contractions, and the levels of mediators were measured with resiniferatoxin treatment., Methods: A total of 35 female Wistar rats were randomly divided into a sham or bladder outlet obstruction group, and rats in each group were given vehicle or resiniferatoxin. Incomplete urethral ligation was applied to the bladder outlet obstruction group. After cystometry, the intravesical level of prostaglandin E 2 and adenosine 5'-triphosphate was measured in the instilled perfusate collected. Naftopidil was given at the time of cystometry., Results: In bladder outlet obstruction rats, non-voiding contractions, bladder capacity, and the intravesical levels of prostaglandin E 2 and adenosine 5'-triphosphate were markedly increased compared with sham rats. Naftopidil decreased non-voiding contractions, enlarged the bladder capacity, and decreased the intravesical levels of prostaglandin E 2 and adenosine 5'-triphosphate. Resiniferatoxin enhanced non-voiding contractions. The effects of naftopidil on non-voiding contractions and the intravesical level of prostaglandin E 2 , but not adenosine 5'-triphosphate, were tolerant to resiniferatoxin., Conclusions: In bladder outlet obstruction rats, one cause of generation of non-voiding contractions might be bladder wall distension, but not transient receptor potential cation channel V1. The increase in intravesical prostaglandin E 2 might also be associated with the generation of non-voiding contractions. Naftopidil inhibits the increase in non-voiding contractions and decreases the intravesical level of prostaglandin E 2 , which are independent of transient receptor potential cation channel V1., (© 2019 The Japanese Urological Association.)

Purpose: To predict the persistence of storage symptoms after transurethral resection of the prostate (TURP) using a nomogram derived from the ice water test (IWT)., Methods: The IWTs of 73 men with lower urinary tract symptoms and prostatic bladder outlet obstruction were retrospectively analyzed. The strength of the detrusor contraction was approximated by using the detrusor gradient of Δp det /Δt at maximum detrusor pressure and the area under the curve. The parameters were utilized in a nomogram, which facilitated a severity categorization from 1 to 10. Patients with a positive IWT in the categories 1 to 2 were assigned to group A, categories 3 to 4 to group B and categories 5 and higher to group C. After TURP, patients with persisting storage symptoms were offered a botulinum toxin injection., Results: There were 32 patients (44%) with negative and 41 patients (56%) with positive IWTs. Patients with negative IWTs were classified in category 1. Regarding patients with positive IWTs, 14 (34%) were correlated to group A, 14 (34%) to group B, and 13 (32%) to group C. The necessity of a subsequent botulinum toxin injection correlated significantly with a higher nomogram category (P < .001) as well as higher severity categorization (P < .001). In multivariate analysis, the nomogram category was an independent predictor for botulinum toxin injection (P = .002, OR, 6.9, CI, 2.0-23.9)., Conclusion: The quantification of the detrusor contraction during the IWT allowed stratification of patients in risk categories for persistent storage symptoms after TURP and the potential need for later botulinum toxin injections., (© 2019 Wiley Periodicals, Inc.)

We aimed to develop and validate a clinical nomogram predicting bladder outlet obstruction (BOO) solely using routine clinical parameters in men with refractory nonneurogenic lower urinary tract symptoms (LUTS). A total of 750 eligible patients ≥50 years of age who had previously not responded (International Prostate Symptom Score [IPSS] improvement <4 points) to at least three different kinds of LUTS medications (including a-blocker) for the last 6 months were evaluated as subcohorts for nomogram development (n = 570) and for split-sample validation (n = 180). BOO was defined as Abrams-Griffiths number ≥40, or 20-39.9 with a slope of linear passive urethral resistance ratio >2 cmH 2 O ml -1 s -1 . A stepwise multivariable logistic regression analysis was conducted to determine the predictors of BOO, and b-coefficients of the final model were selected to create a clinical nomogram. The final multivariable logistic regression model showed that age, IPSS, maximum urinary flow rate, postvoid residual volume, total prostate volume, and transitional zone index were significant for predicting BOO; these candidates were used to develop the final nomogram. The discrimination performance of the nomogram was 88.3% (95% CI: 82.7%-93.0%, P < 0.001), and the nomogram was reasonably well-fitted to the ideal line of the calibration plot. Independent split-sample validation revealed 80.9% (95% CI: 75.5%-84.4%, P < 0.001) accuracy. The proposed BOO nomogram based solely on routine clinical parameters was accurate and validated properly. This nomogram may be useful in determining further treatment, primarily focused on prostatic surgery for BOO, without impeding the detection of possible BOO in men with LUTS that is refractory to empirical medications., Competing Interests: None