Urethral Resistance Research Articles

Effect of Aging on Storage and Voiding Function in Women with Stress Predominant Urinary Incontinence

We investigated age related changes in urodynamic parameters in 2 large cohorts of women planning stress urinary incontinence surgery. Using a standardized protocol we obtained urodynamic parameters for participants in SISTEr (Stress Incontinence Surgical Treatment Efficacy Trial) and TOMUS (Trial of Mid-Urethral Slings) undergoing baseline noninvasive flow followed by filling cystometrogram and pressure flow study. The bladder contractility index (defined as detrusor pressure at maximum flow+5×maximum flow) and detrusor hypocontractility (defined as detrusor pressure at maximum flow less than 10 cm H2O) were also characterized. Patients excluded from analysis had undergone prior stress urinary incontinence surgery or had prolapse stage greater than II. Propensity score analysis controlled for the potential bias of combining participants from 2 clinical trials. Linear and logistic regression analysis adjusting for propensity score quintile was done to assess the association of age and an age cutoff (less than 65 vs 65 or greater years) with urodynamic parameters. A total of 945 women (468 in SISTEr and 477 in TOMUS) were included in analysis. Mean age was 50 years in SISTEr (range 27 to 75) and 51 years (range 24 to 82) in TOMUS. Noninvasive maximum urinary flow decreased significantly with age (26.2 vs 22 ml per second, p=0.002). Noninvasive flow voiding time increased 2.7 seconds for each 10-year age increment and detrusor pressure at maximum flow decreased 2.1 cm H2O for each 10-year increase in age (each p=0.003). Hypocontractility was more likely in women 65 years old or older (OR 2.89, 95% CI 1.59, 5.27). The bladder contractility index was inversely related to age, decreasing a mean±SD of 7.68±1.96 cm H2O for each 10-year age increase (p<0.001). In these 2 cohorts the observed changes in voiding parameters suggest that detrusor contractility and efficiency decrease with age.

ADX71441, a novel, potent and selective positive allosteric modulator of the GABA(B) receptor, shows efficacy in rodent models of overactive bladder.

The GABAB receptor agonist baclofen reduces urethral resistance and detrusor overactivity in patients with spasticity. However, baclofen's side effects limit its use for the treatment of overactive bladder (OAB). Here, we tested a novel GABAB positive allosteric modulator (PAM) ADX71441 in models of OAB in mice and guinea pigs. Mice were left untreated or given (p.o.) vehicle (1% CMC), ADX71441 (1, 3, 10 mg kg(-1) ) or oxybutynin (100 mg kg(-1) ; Experiment 1) or vehicle (1% CMC), baclofen (1, 3, 6 mg kg(-1) ) or oxybutynin (Experiment 2). Treated mice were then overhydrated with water, challenged with furosemide, before being placed into micturition chambers and monitored for urinary parameters. In anaesthetized guinea pigs, intravesical infusion of acetic acid was used to induce OAB and the effects of ADX71441 (1, 3 mg kg(-1) ) or baclofen (1 mg kg(-1) ), administered i.v., on cystometric parameters were monitored. In mice, 10 mg kg(-1) ADX71441 increased urinary latencies, reduced the number of urinary events and the total and average urinary volumes. In guinea pigs, ADX71441 (1 and 3 mg kg(-1) ) increased the intercontraction interval (ICI) and bladder capacity (BC), and reduced micturition frequency (MF) compared to vehicle. At 3 mg kg(-1) ADX71441 completely inhibited the micturition reflex and induced overflow incontinence in five out of 10 animals. Baclofen slightly increased ICI and BC and reduced MF. Our findings demonstrate, for the first time, that a GABAB PAM has potential as a novel approach for the treatment of OAB.

Chronic sacral nerve stimulation as a novel treatment for stress urinary incontinence-A rat model

We propose an animal model to evaluate the effect of chronic sacral nerve stimulation (SNS) on surgically induced intrinsic sphincter deficiency (ISD) secondary to transabdominal urethrolysis (U-Lys). Twenty-five 6-week old virgin female Sprague-Dawley rats were divided into four groups: control (CTRL), U-Lys only, SNS only, and both (U-Lys/SNS). Groups CTRL (N = 5) and U-Lys only (N = 5) were maintained in the animal research facility in standard fashion for 2 weeks. Groups SNS only (N = 5) and U-Lys/SNS (N = 10) underwent chronic SNS for 6 continuous hours daily for 2 weeks. Retrograde leak point pressure (RLPP) was measured at baseline and at 2 weeks following observation or treatment. Five consecutive RLPP measurements were averaged per measurement cycle. SAS 9.3 was used to evaluate means and standard deviation. Baseline mean RLPP was 65 mmHg. The U-Lys only group mean RLPP at initial urethrolysis (58 mmHg) decreased (31 mmHg, P < 0.0001) after 2 weeks of observation. In the SNS only group, mean RLPP significantly increased from baseline (73 mmHg) after 2 weeks of chronic SNS stimulation (80 mmHg, P < 0.01). In rats that underwent both U-Lys and SNS stimulation mean RLPP was initially low (46 mmHg) after U-Lys and then significantly increased after 2 weeks of SNS (65 mmHg, P < 0.0001). Chronic SNS mediates an improvement in urethral sphincteric function at stimulation parameters similar to those used in humans for treating voiding dysfunction. SNS increased urethral resistance in rats with and without surgically induced ISD.

Prognostic factors of endoscopic treatment of vesicoureteral reflux in spinal cord injured patients

IntroductionVesicoureteral reflux (VUR) is an important complication in patients with spinal cord injury due to its frequency and morbidity. One of the most extended therapeutic options is endoscopic injection of obliteration substances in the urethral meatus. ObjectiveTo analyze the prognostic factors of VUR treatment using obliterative substances in patients with spinal cord injury. Material and methodsA prospective study was performed in a cohort of 76 patients (age 48.9±14.4 years), of both genders, with spinal cord injuries, who underwent endoscopic treatment of the VUR during the years 2008–2011. In all the patients, a clinical history was obtained and a pre-operative videourodynamic study was performed. Another study was carried out at 7.32 months (standard deviation: 6.28 months) of the intervention. Treatment consisted in endoscopic injection of dextranomer/hyaluronic acid copolymer (62 cases) and polydimethylsiloxane (14). The statistical tests applied were the Fisher's exact test and the Student's T test comparing the means. Bilateral significance level was established at 95%. ResultsResolution of VUR was achieved in 46 cases (61%). The statistically significant prognostic factors were age (younger aging cured patients), bilaterality and reflects great (greater grade in bilaterality in the cases with persistence of reflux) and presence of neurogenic detrusor overactivity (greater percentage in the cases of reflux persistence). Stress urinary incontinence (greater percentage in cured patients), contractile potency (lower percentage in cured patients) and urethral resistance (greater percentage in cured patients) were also statistically significant prognostic factors. ConclusionsAmong the prognostic factors that affected the endoscopic treatment results of the VUR in patients with neurogenic lower urinary tract dysfunction (NLUTD), anatomical as well as functional factors were found.

Diagnosis of Bladder Outlet Obstruction in Men Using a Near-infrared Spectroscopy Instrument as the Noninvasive Monitor for Bladder Function

To investigate the feasibility and accuracy of the diagnosis of bladder outlet obstruction (BOO) in men using near-infrared spectroscopy (NIRS) as a noninvasive monitor. The study included 94 patients with lower urinary tract symptoms owing to benign prostatic hyperplasia. All patients underwent uroflow rate and post-void residual (PVR) followed by NIRS assessment of BOO and pressure-flow study for diagnosis. The results of the NIRS were compared with that of the pressure-flow study. The data of 87 patients were finally enrolled in this study. According to the BOO judged by the NIRS, the 87 patients were divided into an obstruction group (52 cases) and a nonobstruction group (35 cases). The differences in the Abrams-Griffiths number, the linear passive urethral resistance relation value, and urethral resistance factor value between the 2 groups were significant (P ≤.001), indicating the practical significance of the NIRS method in the diagnosis of BOO. Further analysis showed the following: (1) the NIRS has a sensitivity of approximately 68.3%, specificity of 62.5%, and average diagnosis coincidence rate of 66.7% compared with the "gold standards"-Abrams-Griffiths number, and (2) the sensitivity (68.3%) and the coincidence rate (66.7%) of the NIRS diagnosis for BOO were significantly higher than the sensitivity (33.3%) and the coincidence rate (48.3%) of the examination method of free uroflow rate + PVR. Compared with the "maximum uroflow rate (Qmax) + PVR", NIRS can be more accurate and noninvasive for the diagnosis of BOO in men; this approach provides a new noninvasive method of high clinical value.

Significant decrease of extracellular matrix in prostatic urethra of patients with benign prostatic hyperplasia.

Benign prostatic hyperplasia (BPH) nodules increase urethral resistance, resulting in "pressure" of tissue expansion to the urethra and leads to an increase in outflow resistance, accompanied by characteristic lengthening of the prostatic urethra. The goal of this investigation was to analyze and quantify changes of the histological components in the prostatic urethra of patients with BPH and compare with a control group. Prostatic urethra tissue samples were obtained from ten patients (age range 63 to 79 years, mean 66) with clinical symptoms of bladder outlet obstruction who had undergone open prostatectomy. The ten control group samples (urethral tissue samples from the transitional zone) were collected from prostates obtained during autopsy of accidental death adults of less than 25 years. The Volumetric density (Vv) of the histological components was determined with stereological methods from 25 random fields per sample using the point-count method with a M-42 grid test system. The quantitative data were analyzed using the Kolmogorov-Smirnov and Mann-Whitney U tests. The Vv (mean±SD) in the control and BPH groups respectively were: 20.3±0.3 and 17.12±1.1 in the elastic fiber system (p<0.007); and 29.7±1.9 and 25.1±2.4 in the collagen compartment (p<0.03). Smooth muscle cell volume was increased in BPH cases, 49.9±0.4 and 52.3±2.3 (not statistically significant). BPH nodules caused a significant decrease of elastic system fibers and collagen in prostatic urethra.

Active opening out of the urethra questions the basis of the Valentini–Besson–Nelson mathematical model

Dear Editor, The mechanics of micturition are an important step in the understanding and therefore, potential treatment of micturition dysfunctions. Mathematical models such as the Valentini– Besson–Nelson (VBN) mathematical model are an important step in this process [1]. This is a field that has also occupied our attention for some years. We are concerned at a singular omission from the VBN model, the active opening out of the urethra by external striated muscle forces (Fig. 1). Active opening out of the urethra would have major effects on the VBN model. It is clear from Fig. 1 that the anterior vaginal wall, and therefore the urethra, is stretched backwards, extending urethral elasticity, a pre-requisite for obtaining a smooth surface for urine flow. In this context, urethral elasticity ceases to be a dominant factor in the calculation. It is likely that the rhabdosphincter would relax during micturition. Whether it does or not, our radiological micturition studies show no urethral compression at the midurethra. On the contrary, they clearly demonstrate opening out of the whole urethral tube, often to double the original diameter. Therefore, this element of the VBN equation must also be questioned. Our modelling of the anatomical structures of the urethral wall indicates that the pressure generated by detrusor contraction is nowhere near sufficient to expel urine in the absence of this external striated mechanism [2], mathematically confirming our observations of active opening. Active opening must also confound the detrusor element of the VBN equation, as the pressure measured is a function of the urethral resistance and in turn, the radius. This is obvious when one considers that paraplegic patients cannot urinate spontaneously and have to be catheterized. We were not able to check reference [3]. Our bench and computer modelling indicate that intraurethral resistance is exponentially related, inversely to the 5th power of the urethral radius [4].

Detrusor Underactivity in Men Following Radical Retropubic Prostatectomy - Prevalence, Importance and Evaluation

Stress Urinary Incontinence is a common morbidity after radical prostatectomy. It is estimated that up to 6 % of men who undergo radical prostatectomy will subsequently have a procedure for correction of stress urinary incontinence. Over the past two decades, the interest in treating male stress incontinence with sling procedures has increased. The success of sling surgery is predicated on ventral urethral compression to maintain continence while continuing to allow spontaneous voiding. In some men however, the increased urethral resistance provided by the sling can precipitate urinary retention, specifically those with detrusor underactivity. This paper will review: a) the difficulty in defining detrusor underactivity in men after radical prostatectomy; b) the incidence of urodynamic detrusor underactivity after radical prostatectomy; and c) the potential importance of this finding in men seeking treatment for post radical prostatectomy incontinence.

The role of pelvic and perineal striated muscles in urethral function during micturition in female rabbits

To evaluate the role of pelvic and perineal striated muscles on urethral function during micturition. Pubococcygeus, or both bulbospongiosus and ischiocavernosus muscles were electrically stimulated during the voiding phase of micturition, and bladder and urethral pressure were simultaneously recorded in urethane anesthetized female rabbits. Bladder and urethral function were assessed measuring urodynamic and urethral pressure variables obtained before and during the stimulation of muscles. Two-tail paired t-tests were carried out in order to determine significant differences (P < 0.05) between groups. Electric stimulation of the pubococcygeus during voiding decreased voiding efficiency and voided volume, whereas residual volume, the duration of voiding, the interval between bladder contraction and urethral resistance increased. Simultaneously, there was an increase in maximum urethral pressure, as well as an increase in the pressure to return to baseline and in the pressure required to close the urethra. Electrical stimulation of bulbospongiosus and ischiocavernosus muscles increased voiding efficiency, voiding duration, and the maximal pressure in bladder. Meanwhile, the maximal urethral pressure, the time related to the rise of urethral pressure, and the urethral pressure required to close the urethra decreased. The stimulation of pelvic and perineal muscles have opposing roles in urethral function during micturition. Pubococcygeus muscles facilitate urethral closure, while they inhibit bladder contraction. In contrast, bulbospongiosus and ischiocavernosus muscles prevent urethral contraction while they promote bladder contraction.

Factores pronósticos del tratamiento endoscópico del reflujo vesicoureteral en pacientes con lesión medular

IntroductionVesicoureteral reflux (VUR) is an important complication in patients with spinal cord injury due to its frequency and morbidity. One of the most extended therapeutic options is endoscopic injection of obliteration substances in the urethral meatus. ObjectiveTo analyze the prognostic factors of VUR treatment using obliterative substances in patients with spinal cord injury. Material and methodsA prospective study was performed in a cohort of 76 patients (age 48.9±14.4 years), of both genders, with spinal cord injuries, who underwent endoscopic treatment of the VUR during the years 2008 to 2011. In all the patients, a clinical history was obtained and a pre-operative videourodynamic study was performed. Another study was carried out at 7.32 months (standard deviation: 6.28 months) of the intervention. Treatment consisted in endoscopic injection of dextranomer/hyaluronic acid copolymer (62 cases) and polydimethylsiloxane (14). The statistical tests applied were the Fisher's exact test and the Student's T test comparing the means. Bilateral significance level was established at 95%. ResultsResolution of VUR was achieved in 46 cases (61%). The statistically significant prognostic factors were age (younger aging cured patients), bilaterality and reflects great (greater grade in bilaterality in the cases with persistence of reflux) and presence of neurogenic detrusor overactivity (greater percentage in the cases of reflux persistence). Stress urinary incontinence (greater percentage in cured patients), contractile potency (lower percentage in cured patients) and urethral resistance (greater percentage in cured patients) were also statistically significant prognostic factors. ConclusionsAmong the prognostic factors that affected the endoscopic treatment results of the VUR in patients with neurogenic lower urinary tract dysfunction (NLUTD), anatomical as well as functional factors were found.

Urodynamic Effects of Volume-adjustable Balloons for Treatment of Postprostatectomy Urinary Incontinence

To evaluate the urodynamic changes in patients treated with Adjustable Continence Therapy for men (ProACT) for postprostatectomy incontinence and to explore the clinical and urodynamic preimplantation parameters as predictors of clinical outcome. Patients underwent urodynamic studies before and after ProACT implantation. ProACT was considered successful if patients used none or 1 dry precautionary pad and nonsuccessful if the patient reported≥1 wet pad/d. The pre- and postimplantation assessments were retrospectively compared within and between the success and nonsuccess groups. Multivariate logistic regression analysis was performed to investigate the association between the preimplantation variables and the clinical outcomes of ProACT implantation. A total of 49 patients were included, 37 with successful and 12 with nonsuccessful clinical outcome. Postimplantation urodynamic studies were performed a median of 9 months after ProACT implantation. In the successfully treated patients, maximum free flow rate, bladder contractility index, maximum of bladder contractility parameter W, and bladder voiding efficiency were significantly lower after implantation. The detrusor pressure at maximum flow rate, postvoid residual urine volume, and bladder outlet obstruction index were significantly higher. A longer duration of urinary incontinence, the use of >5 pads daily, and a smaller cystometric bladder capacity were all independently associated with nonsuccessful clinical outcome after ProACT implantation. ProACT implantation with successful clinical outcome resulted in greater urethral resistance during voiding and reduced bladder contraction strength. A longer duration of incontinence, the use of >5 pads daily, and a smaller cystometric bladder capacity were independent predictors of unsuccessful clinical outcomes, suggesting ProACT implantation should be considered sooner, rather than later, after conservative treatment of postprostatectomy incontinence has failed.

Re-Adjustable Male Slings

Re-adjustable male slings are well established and should be offered to incontinent men with mild, moderate or severe incontinence. However, they should be able to interrupt their stream. Solely the slight increase of the urethral resistance (10 - 15 cmH20) supporting the smooth muscle component will provide continence for such patients. Argus, Remeex and Atoms allow exactly setting the urethral resistance to a level, which will provide continence thus avoiding obstructive voiding. Implantation may be carried out retropubically (Remeex), via a transobturator route (Atoms) or alternatively (Argus). The success rates after more than one-year follow-up come up to 84%. Intraoperative bladder perforations may occur in 6% - 11%, late complications are infections possibly leading to explantation in 8% - 12%. Postoperative perineal pain and/or numbness may be present.

Defining the Degree of Intravesical Prostatic Protrusion in Association With Bladder Outlet Obstruction

PurposeThe present study was done to define the degree of intravesical prostatic protrusion (IPP) causing bladder outlet obstruction (BOO) in patients with benign prostatic hyperplasia (BPH)/lower urinary tract symptoms.Materials and MethodsWe retrospectively evaluated 239 patients with BPH, analyzing age, IPP, prostate volume, International Prostate Symptom Score (IPSS), and the results from a pressure-flow study. Urethral resistance was quantified by using the BOO index (BOOI), according to the formula BOOI=PdetQmax-2×Qmax (where Pdet is detrusor pressure at the peak flow rate and Qmax is peak flow rate). BOO was defined by a BOOI above 40. Patients with a BOOI below 20 were excluded. Patients were classified into two groups (obstructed and unobstructed groups) by the BOOI. Correlations were determined by logistic regression analysis, and receiver operating characteristic curves were plotted to estimate the optimal cutoff for IPP.ResultsThere were significant differences in total prostate volume, postvoiding residual urine (PVR), IPP, and Qmax (p<0.001, p<0.001, p<0.001, and p=0.026, respectively) between the obstructed and unobstructed groups, but there were no significant differences in age (p=0.653), IPSS total score (p=0.624), or quality of life score (p=0.138). IPP had a significant prognosis (p<0.001) but was weakly correlated with prostate volume (p=0.026). The correlation coefficients between IPP and Qmax, PVR, prostate volume, and BOO were 0.551, -0.159, 0.225, and 0.391, respectively. For IPP, the area under the curve was 0.759 (95% confidence interval, 0.657 to 0.861) and the cutoff to indicate BOO was 5.5 mm with 66.7% sensitivity and 80.5% specificity.ConclusionsAn IPP exceeding 5.5 mm was significantly associated with BOO.

Study of the influence of pelvic prolapse in the lower urinary tract micturation phase in the female

ObjectivesPelvic floor prolapse is a frequent condition in the woman, which in addition to anatomical alterations, may cause lower urinary tract dysfunction. We intend to verify the alterations of the micturation phase in patients with pelvic prolapse. Material and methodsA cross-sectional cut off study was performed in a series of 102 women, mean age 66.8 years (standard deviation 9.6 years), diagnosed of urinary obstruction and pelvic prolapse and a prospective longitudinal study in a cohort of 21 patients of the previous series operated on for the prolapse. The patients were subjected to clinical examinations to determine the type and grade of public prolapse and to a urodynamic study. ResultsA significant direct correlation was observed between the grade of cystocele and uterine prolapse and a significant correlation, but in inverse sense, between the grade of uterine prolapse and that of the enterocele. The patients with a greater grade of uterine prolapse had greater urethral resistance by the URA parameter. A tendency toward significance regarding the postsurgical variation of the Urethral Resistance Average (URA) that decreased after the surgery, and the W80-20 (detrusor contractility), that increased after it, was observed. ConclusionsPelvic prolapses affect the micturation phase. This involvement occurs both in the case of the cystoceles and in uterine prolapses and in the posterior compartments (rectocele and enterocele). Furthermore, an improvement is observed in the bladder contractility with the surgery of the pelvic prolapse.

Anatomical and Manometric Comparison of Perineal and Transscrotal Approaches to Artificial Urinary Sphincter Placement

We compared cuff sites and assessed anatomical and manometric differences between the transscrotal and perineal approaches to artificial urinary sphincter placement in fresh male cadavers. Artificial urinary sphincter implantation using perineal and transscrotal incisions was performed in 15 fresh male cadavers. The artificial urinary sphincter cuffs were placed as proximal as possible using each approach. After measuring urethral circumference at each cuff site, an appropriately sized cuff was placed at each location. The 61 to 70 cm H(2)O pressure reservoir and control pump were then connected to the cuffs. Retrograde leak point pressure was assessed sequentially across each cuff. The paired t test was used to compare urethral circumference and retrograde leak point pressure between the 2 approaches. Mean urethral circumference using the perineal and transscrotal approaches was 5.38 (range 3.2 to 7.5) and 3.81 cm (range 3 to 4.5), respectively (p <0.0001, 95% CI of difference 0.99-2.13). Mean retrograde leak point pressure using the perineal and transscrotal approaches was 90.1 and 64.9 cm H(2)O, respectively (p = 0.0002, 95% CI of difference 13.7-33.5). On visual inspection of cuff sites, the perineal approach was more proximal on the urethra than the transscrotal approach. While the transscrotal approach to artificial urinary sphincter placement has the advantage of technical ease, the anatomical and manometric findings of this cadaver study suggest that the perineal approach offers a more proximal cuff location, more robust urethral size and more effective urethral coaptation than the transscrotal approach.

Effects of propiverine hydrochloride, an anticholinergic agent, on urethral continence mechanisms and plasma catecholamine concentration in rats

Anticholinergics are used to treat overactive bladder. Anticholinergic agents such as propiverine hydrochloride reportedly increase plasma catecholamine levels in rats. It is also known that active urethral closure mechanisms prevents stress urinary incontinence (SUI), which is enhanced by central and peripheral noradrenergic system activation. Therefore, we examined the influence of propiverine hydrochloride on urethral anti-incontinence function in rats. Adult female rats were divided into propiverine and vehicle-treated groups. The propiverine group was given propiverine orally once a day for 2 weeks, after which urethral function and plasma concentrations of catecholamine (dopamine, norepinephrine, epinephrine) were tested. Urethral baseline pressure measured by a microtransducer-tipped urethral catheter and leak-point pressure during passive intravesical pressure elevation were significantly increased in the propiverine group compared with the vehicle group. Plasma norepinephrine and epinephrine levels in the propiverine group were also significantly increased. Propiverine treatment that increases plasma catecholamine levels could contribute to improvement of SUI conditions by increasing urethral resistance.

Bladder outlet obstruction number- a good indicator of infravesical obstruction in patients with benign prostatic enlargement?

The objective of our study was to evaluate bladder outlet obstruction number (BOON) in order to predict infravesical obstruction in patients with benign prostatic enlargement (BPE). Two hundred patients with proven BPE from daily urological practice at the Urology Department of the Sarajevo University Clinical Centre were covered by a prospective study in period 2009-2011. All patients completed International Prostatic Symptom Score, their mean voided volume urine was determined from frequency-volume chart and their prostate volume was determined by transabdominal ultrasound. Subsequently, the patients had free uroflowmetry and they underwent complete urodynamic studies. BOON was calculated using the formula: prostate volume (cc)-3 x Qmax (ml/s)-0.2 x mean voided volume (ml). A satisfactory area under the curve (AUC) was obtained for the prediction of obstruction according to bladder outlet obstruction index, Schaefer obstruction class nomogram and group specific urethral resistance factor , with AUC of 0.83 (p<0.001). Following the comparison of different cut-off values of BOON according to the obstruction, the BOON >-20 has been found to be the most accurate obstruction indicator (sensitivity 76.5% and specificity 68.2%), with posttest probability of 77%. The BOON may be used in daily urological practice as a valid, non-invasive indicator of infravesical obstruction in patients with BPE, with a possibility of correct classification of obstruction in approximately 75% of the cases. Transabdominal ultrasound has shown to be applicable to the BOON formula in determining prostate volume.

Experimental study of therapy of bone marrow mesenchymal stem cells or muscle‐like cells/calcium alginate composite gel for the treatment of stress urinary incontinence

To explore the myoblast formation around the urethra and increase in urethral resistance of bone marrow mesenchymal stem cells or muscle-like cells/calcium alginate composite gel injection therapy and effect on LPP in SUI rat model. Isolation, cultivation, and identification of SD rat bone marrow mesenchymal stem cell were performed. 5-Azacytidine was introduced to induce muscle-like cells. SUI was produced in 72 6-week-old female Sprague-Dawley rats, which were divided into four groups: stem cell-gel group, muscle-like cell-gel group, Gel group, and mock control group. One, 4, and 8 weeks after injection, the leak point pressure (LPP) was measured. HE staining of Desmin and α-skeletal muscle actin (α-SMA) were performed. At 4 and 8 weeks after injection in stem cell-gel group and muscle-like cell-gel group, growth of blood vessels gradually increased at gel edge, BMSC, and muscle-like cells gathered around the new blood vessels observed by fluorescence tracer, muscle-like cells grew into elongated spindle-like cells, Desmin, and α-SMA staining were obviously positive expression. LPP determinations of the mock control group compared with the Gel groups were significantly different. Compound of BMSC, muscle-like cells, and calcium alginate composite gel has the potential to differentiate into muscle cells in the microenvironment of SUI rat model. It is found by LPP measurement that the correlation between the increase in urethral resistance and the volume effect of calcium alginate gel is high.

Resistive Index of Prostate Capsular Arteries: A Newly Identified Parameter to Diagnose and Assess Bladder Outlet Obstruction in Patients with Benign Prostatic Hyperplasia

We evaluated the association of the resistive index of the prostate capsular arteries and bladder outlet obstruction severity in men with benign prostatic hyperplasia. A total of 74 patients histologically diagnosed with benign prostatic hyperplasia were ultimately enrolled in this prospective study. Urodynamics were performed by a urologist to determine bladder outlet obstruction. Baseline parameters measured in patients with benign prostatic hyperplasia were the prostate capsular artery resistive index, International Prostate Symptom Score, quality of life score, total prostate and transition zone volume, and the transition zone index. ROC curves were produced to calculate the ROC AUC and evaluate the diagnostic performance of the prostate capsular artery resistive index, International Prostate Symptom Score, obstructive symptoms, total prostate and transition zone volume, and the transition zone index for bladder outlet obstruction. Significant difference between patients with and without bladder outlet obstruction was observed in the resistive index, which showed the highest coefficient with the degree of obstruction (r = 0.712, p <0.0001). At a cutoff of 0.69 the resistive index distinguished patients with and without bladder outlet obstruction with 78% sensitivity and 86.4% specificity. The prostate capsular artery resistive index had the maximum AUC of 0.823. The prostate capsular artery resistive index is significantly higher in patients with benign prostatic hyperplasia related bladder outlet obstruction than in those without such obstruction. The resistive index might serve as a novel indicator to diagnose and assess bladder outlet obstruction in patients with benign prostatic hyperplasia.

Lower Urinary Tract Symptoms and Video-Urodynamic Characteristics of Women with Clinically Unsuspected Bladder Outlet Obstruction.

To analyze the lower urinary tract symptoms (LUTS) and video-urodynamic characteristics of women with clinically unsuspected bladder outlet obstruction (BOO). From 1997 to 2010, a total of 1605 women with bothersome LUTS received video-urodynamic study in our unit. We reviewed the charts of 212 women diagnosed with BOO based on video-urodynamic criteria and 264 women without abnormal findings. LUTS and urodynamic parameters were compared between obstructed and unobstructed cases and among the BOO subgroups. The mean ages of the BOO (58.2 years) and control groups (58.8 years) were similar. The mean values of detrusor pressure at maximum urinary flow rate (Pdet Qmax )/maximum flow rate (Qmax ) of the BOO and control groups were 51.83 cm H2 O/10.22 mL/s versus 18.81 cm H2 O/20.52 mL/s. In the BOO group, cinefluoroscopy revealed dysfunctional voiding in 168 patients (79.2%), urethral stricture in 17 (8.0%), and bladder neck dysfunction in 27 (12.7%). Patients with dysfunctional voiding had significantly lower urethral resistance compared with the other two BOO subgroups. Combined lower urinary tract symptoms were present most often in all BOO patients (69.3%), followed by isolated storage symptoms (30.2%) and isolated voiding symptoms (0.5%). Seventy-seven patients (37.3%) had dysuria and 79 patients (36.3%) had frequency as their main symptom. Women with BOO usually have nonspecific LUTS. Dysfunctional voiding was the most common form among women with clinically unsuspected BOO, but the degree of obstruction was less severe than with primary bladder neck obstruction and urethral stricture.