Emerging links between non‐neurogenic lower urinary tract symptoms secondary to benign prostatic obstruction,metabolic syndrome and its components: A systematic review

We carried out a systematic review in order to determine the connection between lower urinary tract symptoms secondary to bladder outlet obstruction and metabolic syndrome with its components. We searched the Cochrane Central Register of Controlled Trials, PubMed, EMBASE, the Cochrane Database of Systematic Review and Web of Science from their inception until January 2015 to identify all eligible studies on the effect of metabolic syndrome (or component factors) on the presence or severity of lower urinary tract symptoms/bladder outlet obstruction in men. This analysis was carried out according to the STrengthening the Reporting of OBservational studies in Epidemiology guidelines. In total, 19 studies were identified as eligible for this systematic review. The quality assessment score was ≥50% in more than half of the studies (11/19). The evidence synthesis showed a positive association between metabolic syndrome, number of components and lower urinary tract symptoms/bladder outlet obstruction. In particular, the major endocrine aberrations of this connection are central obesity and hypertriglyceridemia. The links between insulin resistance and lower urinary tract symptoms/bladder outlet obstruction should be better investigated. Ethnic disparities in all examined studies showed a different impact of metabolic syndrome on lower urinary tract symptoms/bladder outlet obstruction severity and such influence still remain unclear. The relationship between metabolic syndrome and lower urinary tract symptoms/bladder outlet obstruction open the way for introducing physical activity and diet as recognized first‐line interventions for treating lower urinary tract symptoms. However, this connection should be investigated in two different ethnic cohorts (i.e. Asian vs Caucasian) in order to better understand the impact of ethnic disparities on metabolic syndrome and lower urinary tract symptoms/bladder outlet obstruction severity.     

Chronic bladder ischemia and oxidative stress: New pharmacotherapeutic targets for lower urinary tract symptoms

Chronic bladder ischemia is potentially a common cause of lower urinary tract symptoms in the elderly. Epidemiological studies have shown a close association between lower urinary tract symptoms and vascular risk factors for atherosclerosis, and investigations using transrectal color Doppler ultrasonography have shown a negative correlation between decreased lower urinary tract perfusion and International Prostate Symptom Score in elderly patients with lower urinary tract symptoms. Bladder blood flow is also known to decrease in men with bladder outlet obstruction as a result of benign prostatic hyperplasia. Studies in animal models suggest that chronic bladder ischemia and repeated ischemia/reperfusion during a micturition cycle might produce oxidative stress, leading to denervation of the bladder and the expression of tissue‐damaging molecules in the bladder wall, which could be responsible for the development of bladder hyperactivity progressing to bladder underactivity. The effects of drugs with different mechanisms of action; for example, α₁‐adrenoceptor antagonists, phosphodiesterase type 5 inhibitors, free radical scavengers and β₃‐adrenoceptor agonist, have been studied in animal models of chronic bladder ischemia. The drugs, representing different treatment principles for increasing blood flow and decreasing oxidative stress, showed protective effects not only on urodynamic parameters, but also on negative effects on muscle contractility and on detrimental structural bladder wall changes. Improvement of lower urinary tract perfusion and control of oxidative stress can be considered new therapeutic strategies for treatment of bladder dysfunction induced by chronic ischemia.     

Urodynamics: Examining the Current Role of UDS Testing. What is the Role of Urodynamic Testing in Light of Recent AUA Urodynamics and Overactive Bladder Guidelines and the VALUE Study?

Urodynamics testing is a diagnostic assessment of the lower urinary tract system composed of multiple tests to obtain physiologic data regarding lower urinary tract function (detrusor and outlet) during storage and emptying. The necessity of urodynamics has been both supported and challenged in various urologic conditions such as urinary incontinence, neurogenic bladder, lower urinary tract symptoms, and bladder outlet obstruction. This review discusses the most recent studies with regards to the utility of urodynamics in current practice, highlighting the recent American Urologic Association Adult Urodynamics and Overactive Bladder Guidelines and the Value of Urodynamic Evaluation study.     

Urodynamics in Female Urology

Urodynamics in female urology are often indicated when empiric or conservative treatment does not improve lower urinary tract symptoms. Based on the expected underlying lower urinary tract dysfunction, the urodynamic evaluation is designed by the clinician to reproduce a patient's symptoms and to identify underlying pathophysiological mechanisms, as well as to analyse other functions of the lower urinary tract which may be relevant for planning further (invasive) treatment. In this review, we describe the available urodynamic tests, the normal findings, and the evidence for the role of urodynamics, and on the specific measurements and parameters used to evaluate female lower urinary tract symptoms.In women with a suspected storage dysfunction, filling cystometry allows identification of detrusor overactivity or reduced bladder compliance as possible underlying causation of overactive bladder. Most women with stress incontinence have other storage and/or voiding symptoms and urodynamics should always be performed prior to invasive treatment. In the minority with pure stress urinary incontinence, urodynamic observations can guide the type of surgery chosen, but this has not yet been shown to change treatment outcome.Voiding dysfunction in women has recently received more research attention and various urodynamic parameters are being evaluated on their ability to distinguish detrusor underactivity from bladder outlet obstruction in pressure-flow studies. Video-urodynamics can provide a useful addition when anatomical information is needed in complex patients (eg, prior surgery or neurogenic patients).Finally, ambulatory urodynamics can be used when symptoms cannot be reproduced or explained by conventional urodynamics.     

梨状腹综合征的尿动力学表现(附二例报道)

目的 探讨梨状腹综合征(PBS)患儿尿动力学表现及临床意义。方法 报告2例男性PBS患儿(年龄分别为12岁和8岁)尿动力学检查结果及其指导临床治疗的意义。结果 2例患儿均表现为下尿路梗阻，剩余尿增多，膀胱容量增大，尿道高压，其中1例表现不稳定膀胱。1例行膀胱颈口电切，尿路梗阻症状缓解。结论 PBS患儿尿动力学主要表现为下尿路梗阻，剩余尿增多。对于梨状腹综合征患儿需及时行尿动力学检查，了解下尿路功能状况，采取相应的治疗措施如膀胱颈口电切等方法解除梗阻，防止上尿路损害发展。     

Relationships between lower urinary tract symptoms and bladder outlet obstruction: Results from the ICS-“BPH” Study

Despite the lack of evidence in the literature for close relationships between lower urinary tract symptoms and bladder outlet obstruction, the majority of urologists rely on symptomatology when selecting patients for prostatic surgery. We investigated the relationships between a wide range of lower urinary tract symptoms from the ICSmale questionnaire and the results of urodynamic pressure and flow studies. We evaluated 933 patients with lower urinary tract symptoms suggestive for bladder outlet obstruction from 12 countries who participated in the ICS-“BPH” study with the ICSmale questionnaire and urodynamic pressure and flow studies. Spearman rank correlation coefficients were obtained between symptoms and measures of bladder outlet obstruction. There was little or no correlation between a wide range of symptoms and the results of free uroflowmetry and pressure and flow studies. From symptoms alone, it is not possible to diagnose bladder outlet obstruction. Pressure and flow studies and symptom profiles measure different aspects of the clinical condition that should be viewed separately in the evaluation and treatment decision of the patient presenting with lower urinary tract symptoms. Neurourol. Urodynam. 17:99–108, 1998. © 1998 Wiley-Liss, Inc.     

Combination of symptom score, flow rate and prostate volume for predicting bladder outflow obstruction in men with lower urinary tract symptoms

PURPOSE: The severity of lower urinary tract symptoms associated with benign prostatic enlargement correlates poorly with bladder outlet obstruction. Since urodynamic studies are presumed to be relatively complex, invasive and not cost-effective, they are not routinely performed by physicians treating men with lower urinary tract symptoms. As a result, a large number of patients are treated for bladder outlet obstruction when in fact obstruction may not be present. Since other noninvasive methods have not been effective for predicting bladder outlet obstruction, we investigated whether a combination of prostate volume, uroflowmetry and the American Urological Association (AUA) symptom index would be reliable for predicting this condition. MATERIALS AND METHODS: We prospectively evaluated 204 men with a mean age plus or minus standard deviation of 66.7 +/- 7.5 years who presented with lower urinary tract symptoms. Each patient completed an AUA symptom index questionnaire and underwent uroflowmetry, post-void residual urine volume measurement, pressure flow study and transrectal ultrasound of the prostate to estimate prostatic volume. We constructed receiver operating characteristics curves using various threshold values for maximum urine flow and prostate volume. Threshold values for maximum urine flow and prostate volume were used alone and combined with the AUA symptom index for predicting bladder outlet obstruction. We selected a cutoff value for maximum urine flow of 10 or less ml. per second and prostate volume of 40 gm. or greater, and used these values with an AUA symptom index of greater than 20 to predict bladder outlet obstruction in the group overall. RESULTS: Differences in the mean symptom index score in men with and without bladder outlet obstruction were not statistically significant. There was no obstruction in 19%, 28.9% and 35% of those with severe, moderate and mild symptoms, respectively. The selected cutoff values of maximum urine flow, prostate volume and symptom score combined correctly predicted obstruction in all 39 patients. Therefore, our combination of cutoff values proved to be highly accurate for predicting bladder outlet obstruction. Sensitivity, specificity, and positive and negative predictive values were 26%, 100%, 100% and 32%, respectively. CONCLUSIONS: Our study showed that combining the AUA symptom index, maximum urine flow and prostate volume reliably predicted bladder outlet obstruction in a small subset of patients only. Although bladder outlet obstruction was correctly predicted by our threshold values of AUA symptom index, maximum urine flow and prostate volume in only 39 men (26%) with obstruction, these patients represent a substantial group in any large urological practice treating male lower urinary tract symptoms.     

Refractory overactive bladder in men: Update on novel therapies

Overactive bladder (OAB) in men is an entity that may be challenging to diagnose and treat, especially in the presence of bladder outlet obstruction. The application of oral medical treatments of lower urinary tract symptoms attributed to benign prostatic hyperplasia has traditionally utilized α-adrenergic blockers and 5α-reductase inhibitors. After failure of oral medical therapies, surgical options are traditionally offered. Even after surgical options are successful, lower urinary tract symptoms that are secondary to OAB persist. These patients merit a trial of antimuscarinic drugs. Additionally, certain patients with concomitant bladder outlet obstruction who have not been surgically relieved can still merit a trial of antimuscarinic drugs without significant risk of developing urinary retention. When these oral antimuscarinic drugs fail, options still remain for treating men with refractory OAB. Successful application of various diagnostic approaches and the initiation of conservative options as well as other options, such as neuromodulation for refractory urgency and urge incontinence, can help the patient. Finally, emerging data support the use of intradetrusor injections of botulinum toxin for refractory OAB.     

Heparin inhibition of increased bacterial adherence following overdistension, ischemia and partial outlet obstruction of the rabbit urinary bladder

While it is well established clinically that urinary tract infection in the presence of outflow obstruction may be associated with difficulty in eradicating bacteria, it is not clear whether this is secondary to the presence of residual urine volume or other local effects of the obstruction such as attenuation of the intrinsic antibacterial defense mechanisms of the mucosal surface. Experiments in our laboratory and others over the past several years have demonstrated that the primary antibacterial defense mechanism of the bladder is the antiadherence effect of the bladder surface mucin layer. Additional studies have shown that heparin can duplicate this antiadherence activity of bladder mucin. The present report demonstrates that one hour of overdistension or ischemia and one week of partial outlet obstruction cause a functional defect in the intrinsic antiadherence effect of the bladder mucosa as evidenced by increased bacterial adherence. This defect can be reversed by heparin exposure prior to bacterial challenge. These results indicate that partial outlet obstruction and its potential sequelae such as overdistension and, particularly, mucosal ischemia, have dramatic adverse effects on the intrinsic antiadherence defense mechanism of the bladder. These effects can be reversed by intravesical exposure to an exogenous anionic polyelectrolyte (heparin).     

Male overactive bladder: The role of urodynamics and anticholinergics

Millions of men suffer from overactive bladder and lower urinary tract symptoms. The adverse effects on quality of life and costs associated with the condition have been well described. In men, the pathophysiology of lower urinary tract symptoms may be from a number of causes including bladder outlet obstruction, detrusor overactivity, or both. Increasing data and clinical experience support the efficacy and safety of anticholinergics in men; the rate of urinary retention has been equal to that of placebo in short-term studies. Urodynamics play a vital role in defining the bladder and/or outlet dysfunction and help direct one’s therapy.     

A PROBABILITY BASED SYSTEM FOR COMBINING SIMPLE OFFICE PARAMETERS AS A PREDICTOR OF BLADDER OUTFLOW OBSTRUCTION

PURPOSE: We explored the relationships of office assessment of lower urinary tract symptoms, transrectal ultrasound measurement and the bladder outlet obstruction index, as derived from pressure flow studies. We also developed and validated a multivariate analysis for predicting the bladder outlet obstruction index. MATERIALS AND METHODS: We evaluated 384 men with lower urinary tract symptoms using the International Prostate Symptom Score, maximum urine flow, post-void residual urine, transrectal ultrasound and urodynamic studies. Data were analyzed by multiple linear regression with continuous variables. A simple algorithm, that is the predicted bladder outlet obstruction index, was created using the best fit variables identified from a derivation set and assessed in a separate validation set. The predicted index was applied to predict the probability of actual obstruction according to office parameters. RESULTS: Maximum urine flow and total prostate volume predicted the bladder outlet obstruction index most completely (adjusted R2 = 0.50, F 75.9, p <0.0001), while other variables were not helpful. These variables were used to create the predicted bladder outlet obstruction index algorithm, antilog10 (2.21 - 0.50 log maximum urine flow + 0.18 log total prostate volume) - 50. In the 42% of patients with a predicted index of greater than 40 there was a 92% risk or positive predictive value of equivocal or worse obstruction, whereas a predicted index of less than 20 in 23% indicated a 4% risk of significant obstruction. CONCLUSIONS: The bladder outlet obstruction index can be predicted from maximum urine flow and prostate volume. Development of the predicted bladder outlet obstruction index algorithm enables the mathematical prediction of obstruction from these simple measures. Using the predicted bladder outlet obstruction index clinicians can determine the risk of obstruction in individuals. In 65% of patients we predicted equivocal or worse obstruction with greater than 90% confidence.     

Causative significance of bladder blood flow in lower urinary tract symptoms

The association between metabolic syndrome and lower urinary tract symptoms has been attracting enormous interest and attention. This enthusiasm is based on the presence of many common risk factors being involved in both metabolic syndrome and lower urinary tract symptoms, as shown by various epidemiological studies. Metabolic syndrome and lower urinary tract symptoms have many pathophysiological features in common, particularly overactive bladder. Herein, we analyze the pathophysiological relationship between metabolic syndrome and lower urinary tract symptoms with a special emphasis on bladder blood flow. We also propose a new treatment strategy for treating lower urinary tract symptoms from the viewpoint of bladder blood flow.     

The effect of a 6FG urethral catheter on urinary flow in benign prostatic hypertrophy.

Free voiding and micturition alongside a fine indwelling urethral catheter of similar voided volumes of urine were recorded for 43 men over 50 years of age. All had benign prostatic hypertrophy. Ten men had no bladder outlet obstruction, seven had clinically questionable obstruction, nine had slight obstruction and 17 had moderate or severe bladder outlet obstruction. I found no statistically significant lowering of peak flow rate when voiding was carried out alongside an indwelling 6FG catheter in subjects with no obstruction and with various degrees of bladder outlet obstruction due to benign prostatic hypertrophy. My findings demonstrate that the lower urinary tract is not a simple hydrodynamic system but a biologically functioning organ. The bladder outflow tract possesses considerable elasticity and accommodation. The present findings justify the use of the fine perurethral catheter technic for urodynamic studies, particularly in subjects with clinically questionable bladder outlet obstruction due to benign prostatic hypertrophy.     

Suture causing urethral meatus stricture: A novel animal model of partial bladder outlet obstruction

Aims

Open surgery is the most commonly used methodological approach for generating a partial bladder outlet obstruction (pBOO) animal model. Surgical suturing closing a part of the urethral meatus induces comparable pathophysiological changes in bladder and renal functions, but the optimum degree of obstruction that closely mimics the clinical pathology of pBOO has not been elucidated. We investigated the optimum obstruction level by performing a comprehensive time‐dependent analysis of the stability and reliability of this novel animal model.

Methods

Six‐ to eight‐week‐old female BALB/c mice were divided into three groups according to the degree of urethral meatus stricture (UMS). Non‐operated mice served as controls, and a pBOO model generated using the traditional method served as a positive control. A cystometric evaluation and long‐term studies were performed to evaluate the validity and reliability of this novel animal model. An additional 35 mice were used to investigate the protein expression levels and histopathological features 24 h and 14 days postoperatively, respectively.

Results

The characteristic cystometry features in the UMS group revealed increased changes in pressure‐related parameters compared with the control. The 1/3 UMS model is an optional pBOO animal model because the cystometric evaluation and histopathological studies revealed a striking resemblance between the 1/3 UMS model and the model generated using the traditional open‐surgery method.

Conclusions

The minimally invasive UMS model required less time and produced minimal alterations in pathophysiologically relevant processes compared with the traditional surgery model. Suturing to cause UMS produced effective and repeatable patterns in bladder function investigations in mice.     

Prostatism. I. The correlation between symptoms, cystometric and urodynamic findings.

One hundred and seven consecutive patients referred with symptoms of bladder outlet obstruction were studied using cystometry and combined pressure-flow-electromyographic investigation. The symptoms of infravesical obstruction were not statistically significantly correlated to the hydrodynamic documentation of increased bladder outlet resistance as judged by maximum flow rate and the calculated urethral resistance. Irritative symptoms such as frequency, nocturia, urgency and urgeincontinence were statistically significantly correlated to the presence of detrusor hyperreflexia. The functional disorder bladder neck dyssynergia was encounterd in 5% of the patients (95% confidence limits 1-10%). This diagnosis cannot be made by conventional urological investigations. It is concluded that objective demonstration of infravesical obstruction is mandatory in the selection of patients with symptoms of lower urinary tract dysfunction for surgery on the prostate or the bladder neck.     

Properties of Ca2+-Mg2+ ATP-ase in rabbit bladder muscle and mucosa: Effect of urinary outlet obstruction

The contractile response of the smooth muscle of the urinary bladder is dependent upon both the entrance of extracellular calcium through receptor-operated calcium channels and the stimulated release of calcium from the sarcoplasmic reticulum. In addition, partial outlet obstruction induces marked alterations in the utilization of intracellular calcium. Although calcium ATP-ase provides the energy for the translocation of intracellular free calcium into storage sites within the sarcoplasmic reticulum, very little is known about the properties of this enzyme in bladder muscle and mucosa. As an initial study, divalent ion specific ATP-ase activity was measured in extracts of rabbit bladder muscle and mucosa from control animals and from rabbits following partial urinary outlet obstruction. In both normal bladder muscle and mucosa, magnesium and calcium ions were equally effective in activating the enzyme. Seven days following partial urinary outlet obstruction, the ATP-ase activity in both bladder muscle and mucosa was significantly depressed by over 70%. The degree of the decreased enzyme activities observed within the muscularis and mucosa would indicate that specific membrane functions supported by divalent-ion-ATP-ase are dysfunctional. This hypothesis is supported by marked alterations in the utilization of intracellular calcium following partial outlet obstruction and the marked dysfunctions in both mucosal permeability and bacterial adherence to mucosa observed following partial outlet obstruction. © 1996 Wiley-Liss, Inc.     

Is the ultrasound‐estimated bladder weight a reliable method for evaluating bladder outlet obstruction?

Study Type – Diagnostic (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? Based on the observation of bladder mass increase in BOO animal models, it has been suggested that it could be possible to determine the presence of male bladder outlet obstruction (BOO) by ultrasound estimated bladder weight (UEBW). In the present study, we tried to reproduce the results correlating UEBW and BOO without success. Furthermore, we could not find any correlation of UEBW and IPSS. Despite some studies emphasizing the value of UEBW as an efficient non‐invasive method to evaluate lower urinary tract obstruction, our data demonstrate that UEBW did not present any individual correlation with clinical and urodynamic BOO.

OBJECTIVE

? To evaluate the correlation between ultrasound‐estimated bladder weight (UEBW) in patients with different degrees of bladder outlet obstruction (BOO).

METHODS

? We evaluated 50 consecutive non‐neurogenic male patients with lower urinary tract symptoms (LUTS) referred to urodynamic study (UDS). All patients self‐answered the International Prostate Score Symptoms (IPSS) questionnaire. After the UDS, the bladder was filled with 150 mL to determine UEBW. ? Patients with a bladder capacity under 150 mL, a previous history of prostate surgery or pelvic irradiation, an IPSS score <8, a bladder stone or urinary tract infection were excluded. ? After a pressure–flow study, the Schafer linear passive urethral resistance relation nomogram was plotted to determine the grade of obstruction: Grades I–II/VI were defined as mild obstruction, Grades III–IV/VI as moderate obstruction, and Grades V–VI/VI as severe obstruction.

RESULTS

? The UEBW was 51.7 ± 26.9, 54.1 ± 30.0 and 54.8 ± 28.2 in patients with mild, moderate and severe BOO, respectively (P= 0.130). The UEBW allowed us to define four groups: (i) UEBW <35 g; (ii) 35 g ≤ UEBW < 50 g; (iii) 50 g ≤ UEBW < 70 g; and (4) UEBW ≥ 70 g. ? We did not find any differences in age, prostate weight, IPSS, PVR, cystometric bladder capacity, presence of detrusor overactive and degree of obstruction in the aforementioned groups.

CONCLUSION

? Despite the fact that some studies have emphasized the value of UEBW as an efficient non‐invasive method for evaluating lower urinary tract obstruction, our study suggests that UEBW does not present any individual correlation with LUTS or objective measurements of BOO.     

Increased penile expression of transforming growth factor and elevated systemic oxidative stress in rabbits with chronic partial bladder outlet obstruction

There is a growing body of evidence to support the direct link between obstructive bladder dysfunction and erectile dysfunction (ED). However, there have been few pathophysiological studies to determine the relationship between lower urinary tract syndrome (LUTS) and ED. As the transforming growth factor-β1 (TGF-β1) that induces the synthesis of collagen in the penile tissues is critical for the development of ED, the first aim of this study was to investigate the expression of TGF-β1 in the penis from male rabbits with chronic partial bladder outlet obstruction (PBOO). Besides, it has been suggested that oxidative stress plays a significant role in the pathophysiological mechanism of ED. Thus, the second aim of this study was to further investigate whether the urinary or serum oxidative stress markers are involved in chronic PBOO-induced penile dysfunction. A total of 16 male New Zealand White rabbits were separated equally into four groups: a control group and PBOO groups obstructed for 2, 4 and 8 weeks respectively. Using the RT-PCR and Western blot analysis, a progressive increase of TGF-β1 in penis was found at 2, 4 and 8 weeks after obstruction. Moreover, the biomarkers for oxidative stress or oxidative damage were significantly detected in the penis of rabbits after PBOO, which include the enhancement of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in urine and plasma, plasma malondialdehyde (MDA) and total antioxidant capacity (TAC), as well as reduction of glutathione (GSH). On the basis of our results, the increase of TGF-β1 and elevated systemic oxidative stress may play key roles to contribute to penile dysfunction after chronic PBOO.     

An atypical bladder diverticulum presented with recurrent peritonitis: case report

Bladder diverticula develop from congenital detrusor muscle defect and frequently present with urinary tract infection, which occurs as a result of urinary stasis in the diverticula. Different clinical presentations, such as bladder outlet obstruction, cyanosis of the lower extremities, intestinal obstruction, ureteral obstruction (which may occur due to direct diverticular compression), and peritonitis due to spontaneous rupture of the diverticula, were reported previously. Here, we report a case with the diagnosis of bladder diverticulum that caused recurrent generalized peritonitis without perforation and mimicked perforated appendicitis.     

Animal models and their use in understanding lower urinary tract dysfunction

This review will highlight appropriate animal models for the study of a number of disorders involving changes to lower urinary tract function. A major hurdle to the development of animal models for human lower urinary tract disorders is that the clinical pathophysiology of the latter mostly remain idiopathic. Acute injury/inflammation of otherwise healthy animals has often been used to study effects on a target tissue/organ. However, these “acute” models may not adequately address the characteristics of “chronic” visceral disorders. In addition, the relevance of observed changes following acute injury/inflammation, in terms of possible therapeutic targets, may not reflect that which occurs in the human condition. We have therefore emphasized the situations when animal models are required to investigate lower urinary tract disorders and what they should set out to achieve. In particular we have discussed the merits and disadvantages of a number of paradigms that set out to investigate specific lower urinary tract disorders or situations associated with these conditions. These include animal models of overactive bladder, stress urinary incontinence, ageing and congenital defects of the urinary tract and bladder pain syndrome. Neurourol. Urodynam. 29:603–608, 2010. Copyright © 2010 Wiley‐Liss, Inc.