Improvement of lower urinary tract dysfunction by a monoacylglycerol lipase inhibitor in mice with spinal cord injury.

AIMS: Activation of the endocannabinoid system by monoacylglycerol lipase (MAGL) blockade may affect the lower urinary tract function. We investigated the effect of an MAGL inhibitor, MJN110, on neurogenic lower urinary tract dysfunction (LUTD) in the mouse model of spinal cord injury (SCI). METHODS: Female C57BL/6 mice that underwent spinal cord transection at T8-10 level were divided into three groups consisting of (1) vehicle-treated SCI mice, (2) 5 mg/kg, or (3) 10 mg/kg of MJN110-treated SCI mice. MJN110 and vehicle were administered intraperitoneally for 7 days from 4 weeks after spinal cord transection. We then conducted awake cystometrograms and compared urodynamic parameters between three groups. The expression of cannabinoid (CB) receptors, TRP receptors, and inflammatory cytokines in L6-S1 dorsal root ganglia (DRG) or the bladder mucosa were evaluated and compared among three groups. Changes in the level of serum 2-arachidonoylglycerol (2-AG) and bladder MAGL were also evaluated. RESULTS: In the cystometrogram, detrusor overactivity (DO) parameters, such as the number of nonvoiding contraction (NVC), a ratio of time to the 1st NVC to intercontraction interval (ICI), and NVC integrals were improved by MJN110 treatment, and some effects were dose dependent. Although MJN110 did not improve voiding efficiency, it decreased bladder capacity, ICI, and residual urine volume compared to vehicle injection. MJN110 treatment groups had lower CB2, TRPV1, TRPA1, and inflammatory cytokines mRNA levels in DRG and bladder mucosa. Serum 2-AG was increased, and bladder MAGL was decreased after MAGL inhibitor treatment. CONCLUSIONS: MAGL inhibition improved LUTD including attenuation of DO after SCI. Thus, MAGL can be a therapeutic target for neurogenic LUTD after SCI.

Sex differences in lower urinary tract function in mice with or without spinal cord injury.

OBJECTIVES: We examined sex differences of lower urinary tract function and molecular mechanisms in mice with and without spinal cord injury (SCI). METHODS: SCI was induced by Th8-9 spinal cord transection in male and female mice. We evaluated cystometrograms (CMG) and electromyography (EMG) of external urethral sphincter (EUS) at 6 weeks after SCI in spinal intact (SI) and SCI mice. The mRNA levels of Piezo2 and TRPV1 were measured in L6-S1 dorsal root ganglia (DRG). Protein levels of nerve growth factor (NGF) in the bladder mucosa was evaluated using an enzyme-linked immunosorbent assay. RESULTS: Sex differences were found in the EUS behavior during voiding as voiding events in female mice with or without SCI occurred during EUS relaxation periods without EUS bursting activity whereas male mice with or without SCI urinated during EUS bursting activity in EMG recordings. In both sexes, SCI decreased voiding efficiency along with increased tonic EUS activities evident as reduced EUS relaxation time in females and longer active periods of EUS bursting activity in males. mRNA levels of Piezo2 and TRPV1 of DRG in male and female SCI mice were significantly upregulated compared with SI mice. NGF in the bladder mucosa showed a significant increase in male and female SCI mice compared with SI mice. However, there were no significant differences in Piezo2 or TRPV1 levels in DRG or NGF protein levels in the bladder mucosa between male and female SCI mice. CONCLUSIONS: We demonstrated that female and male mice voided during EUS relaxation and EUS bursting activity, respectively. Also, upregulation of TRPV1 and Piezo2 in L6-S1 DRG and NGF in the bladder could be involved in SCI-induced lower urinary tract dysfunction in both sexes of mice.

Molecular Mechanisms of Neurogenic Lower Urinary Tract Dysfunction after Spinal Cord Injury.

This article provides a synopsis of current progress made in fundamental studies of lower urinary tract dysfunction (LUTD) after spinal cord injury (SCI) above the sacral level. Animal models of SCI allowed us to examine the effects of SCI on the micturition control and the underlying neurophysiological processes of SCI-induced LUTD. Urine storage and elimination are the two primary functions of the LUT, which are governed by complicated regulatory mechanisms in the central and peripheral nervous systems. These neural systems control the action of two functional units in the LUT: the urinary bladder and an outlet consisting of the bladder neck, urethral sphincters, and pelvic-floor striated muscles. During the storage phase, the outlet is closed, and the bladder is inactive to maintain a low intravenous pressure and continence. In contrast, during the voiding phase, the outlet relaxes, and the bladder contracts to facilitate adequate urine flow and bladder emptying. SCI disrupts the normal reflex circuits that regulate co-ordinated bladder and urethral sphincter function, leading to involuntary and inefficient voiding. Following SCI, a spinal micturition reflex pathway develops to induce an overactive bladder condition following the initial areflexic phase. In addition, without proper bladder-urethral-sphincter coordination after SCI, the bladder is not emptied as effectively as in the normal condition. Previous studies using animal models of SCI have shown that hyperexcitability of C-fiber bladder afferent pathways is a fundamental pathophysiological mechanism, inducing neurogenic LUTD, especially detrusor overactivity during the storage phase. SCI also induces neurogenic LUTD during the voiding phase, known as detrusor sphincter dyssynergia, likely due to hyperexcitability of Aδ-fiber bladder afferent pathways rather than C-fiber afferents. The molecular mechanisms underlying SCI-induced LUTD are multifactorial; previous studies have identified significant changes in the expression of various molecules in the peripheral organs and afferent nerves projecting to the spinal cord, including growth factors, ion channels, receptors and neurotransmitters. These findings in animal models of SCI and neurogenic LUTD should increase our understanding of pathophysiological mechanisms of LUTD after SCI for the future development of novel therapies for SCI patients with LUTD.

Changes in Adenosine Triphosphate and Nitric Oxide in the Urothelium of Patients with Benign Prostatic Hyperplasia and Detrusor Underactivity.

PURPOSE: We investigated changes in the levels of adenosine triphosphate and nitric oxide in the urothelium of men with detrusor underactivity and benign prostatic hyperplasia. MATERIALS AND METHODS: We prospectively enrolled in study 30 men who planned to undergo surgical treatment for benign prostatic hyperplasia. The 15 patients with a bladder contractility index less than 100 were assigned to the detrusor underactivity group while the 15 with a bladder contractility index more than 100 were assigned to the no detrusor underactivity group. Bladder mucosal specimens were collected at surgical prostate resection, and adenosine triphosphate and endothelial nitric oxide synthase were analyzed in these specimens. The levels of adenosine triphosphate and endothelial nitric oxide synthase were compared between the 2 groups. The correlation of urodynamic parameters with adenosine triphosphate and endothelial nitric oxide synthase was assessed in all patients. RESULTS: Mean ± SEM endothelial nitric oxide synthase did not significantly differ between the detrusor underactivity and no underactivity groups (3.393 ± 0.969 vs 1.941 ± 0.377 IU/ml, p = 0.247). However, the mean level of adenosine triphosphate in the detrusor underactivity group was significantly lower than in the no detrusor underactivity group (1.289 ± 0.320 vs 9.262 ± 3.285 pmol, p = 0.011). In addition, in all patients adenosine triphosphate positively correlated with the bladder contractility index (r = 0.478, p = 0.018) and with detrusor pressure on maximal flow (r = 0.411, p = 0.046). CONCLUSIONS: Adenosine triphosphate was significantly decreased in the urothelium in men with detrusor underactivity and benign prostatic hyperplasia, reflecting the change in detrusor function.

Efficacy and Safety of Desmopressin Add-On Therapy for Men with Persistent Nocturia on α-Blocker Monotherapy for Lower Urinary Tract Symptoms: A Randomized, Double-Blind, Placebo Controlled Study.

PURPOSE: We investigated the efficacy and safety of desmopressin add-on therapy for men with persistent nocturia on α-blocker for lower urinary tract symptoms in this placebo controlled study. MATERIALS AND METHODS: The study included men 40 to 65 years old with lower urinary tract symptoms and persistent nocturia despite α-blocker therapy for at least 8 weeks. Patients were randomized to once daily placebo or desmopressin 0.2 mg for 8 weeks. The primary end point was to assess changes in the mean number of nocturia episodes from baseline to the final assessment. Other secondary end points and adverse events were evaluated. RESULTS AND LIMITATION: A total of 86 patients were randomized to treatment, including placebo in 39 and desmopressin 0.2 mg in 47. Baseline characteristics were similar in the 2 groups. The desmopressin add-on group was significantly superior to placebo in terms of the change from baseline in the mean number of nocturia episodes (-1.13 ± 0.92 vs -0.68 ± 0.79, p = 0.034), the changes in nocturnal urine volume (p <0.001), total I-PSS (International Prostate Symptom Score) (p = 0.041), the nocturnal polyuria index (p = 0.001) and ICIQ-N (International Consultation on Incontinence Questionnaire-Nocturia) (p = 0.001), and the willingness to continue (p = 0.025). The incidence of adverse events in the desmopressin add-on group was similar to that in the placebo group. Most adverse events were mild. CONCLUSION: Desmopressin add-on therapy in men 40 to 65 years old with persistent nocturia on α-blocker monotherapy for lower urinary tract symptoms is effective and well tolerated.

Expressions of vaginal endothelial nitric oxide synthase and phosphodiesterase 5 in female sexual dysfunction: a pilot study.

INTRODUCTION AND HYPOTHESIS: The objective was to investigate the expression of endothelial nitric oxide synthase (eNOS) and phosphodiesterase (PDE) 5 in vaginal tissue of premenopausal women experiencing stress urinary incontinence (SUI) with and without sexual dysfunction. METHODS: Women presenting for treatment of SUI were screened using the Female Sexual Function Index (FSFI) and 10 were selected who met the criteria for female sexual dysfunction (FSD) and 10 asymptomatic controls. Vaginal tissue specimens were obtained from those premenopausal women aged ≥40 years who had had sexual activity ≥2 times every month for the last 6 months and who were scheduled to undergo surgery for SUI. FSD criteria was FSFI scores <18 and arousal domain scores <3. The control group had FSFI scores ≥26 and individual domain scores ≥4. The expressions of eNOS and PDE 5 were compared in the two groups using immunofluorescence staining and western blotting. RESULTS: The mean total FSFI scores were 30.4 ± 2.6 and 15.3 ± 2.3 in the control and FSD groups respectively. In immunofluorescence staining, eNOS and PDE5 were localized in the vaginal epithelium. In western blotting, the expressions of eNOS and PDE5 were significantly lower in the FSD group than in the control group (p = 0.003 and p = 0.038 respectively). CONCLUSIONS: eNOS and PDE5 in the vagina may play important roles in the pathophysiology of FSD.

Expression of cannabinoid 1 and, 2 receptors and the effects of cannabinoid 1 and, 2 receptor agonists on detrusor overactivity associated with bladder outlet obstruction in rats.

BACKGROUND: This study investigated changes in the expression of cannabinoid (CB) receptors and the effects of CB1 and CB2 agonists on detrusor overactivity (DO) associated with bladder outlet obstruction (BOO) in rats. METHODS: Male Sprague Dawley rats were randomly assigned to four groups (n = 10) in each group. The control group comprised sham-operated rats. A animals in the BOO, CB1 agonist and CB2 agonist groups all underwent BOO surgery. Three weeks postoperatively, cystometrography (CMG) was performed on all rats. After confirming the presence of DO in the CB1 and CB2 agonist groups, a CB1 agonist (WIN 55,212-2) and a CB2 agonist (CB65) were instilled intravesically, and CMG was repeated. CMG parameters, including the contraction interval (CI) and contraction pressure (CP) were then analyzed. The bladders of rats in all four groups were excised following CMG. Immunofluorescence staining and Western blotting were performed to localize CB1 and CB2 and measure their expression levels in the urothelium and detrusor muscle. RESULTS: The CI was significantly longer and the CP was significantly lower in the CB1 agonist group than in the BOO group. CI and CP in the CB2 agonist group showed the same results. CB1 receptor immunofluorescence staining signals and immunoreactive bands in Western blotting were increased in the BOO group compared with results in the control group. Similarly, results for the CB2 receptor were also increased in the BOO group, although this difference was not significant. The CMG parameters in the BOO group were significantly improved by the inhibitory effects of CB1 and CB2 agonists on BOO-associated DO. The expression of CB1 was significantly increased in the urothelium and detrusor muscle in BOO-associated DO, but no significant change in CB2 expression was observed. CONCLUSIONS: CB1 and CB2 receptors, especially CB1, play a role in the pathophysiology of BOO-associated DO, and could serve as therapeutic targets.

Hyaluronic acid-carboxymethylcellulose reduced postoperative bowel adhesions following laparoscopic urologic pelvic surgery: a prospective, randomized, controlled, single-blind study.

BACKGROUND: To assess the anti-adhesive effect of treatment with hyaluronic acid-carboxymethylcellulose following laparoscopic radical prostatectomy. METHODS: This was a randomized, controlled, single-blind, parallel-group study using hyaluronic acid-carboxymethylcellulose in patients who underwent laparoscopic radical prostatectomy. Sixty patients were enrolled in the study. All patients were randomly assigned to either the hyaluronic acid-carboxymethylcellulose treatment group (n = 30) or the control group (n = 30). Viscera slide ultrasounds and plain X-rays were obtained at enrollment (V0), postoperative week 12 (V1), and 24 (V2). The primary end point was the difference in the excursion distance in the viscera slide ultrasound between V0 and V2. RESULTS: A total of 50 patients completed this study. The average excursion distance at V2 in the experimental group (n = 25) was significantly longer than in the control group (n = 25, 2.7 ± 1.2 vs. 1.3 ± 1.0 cm, respectively; p < 0.001). The differences in the V0 and V2 excursion distances were significantly higher in the control group than in the experimental group (1.48 ± 1.5 vs. 2.9 ± 1.2 cm, respectively; p < 0.001). None of patients showed adverse events associated with the use of hyaluronic acid-carboxymethylcellulose. CONCLUSION: This randomized study demonstrated that hyaluronic acid-carboxymethylcellulose treatment resulted in a reduction in bowel adhesion to the abdominal wall after laparoscopic pelvic surgery and had good clinical safety. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02773251 Date: May 12, 2016.

Evaluation of female overactive bladder using urodynamics: relationship with female voiding dysfunction.

PURPOSE: To investigate the role of urodynamic study (UDS) in female patients with overactive bladder (OAB) analyzing the relationship between OAB symptoms and female voiding dysfunction (FVD). MATERIALS AND METHODS: We analyzed the clinical and urodynamic data of 163 women with OAB symptoms. OAB symptoms were categorized as dry and wet. FVD was described as detrusor underactivity (DUA), which was defined as a maximum flow rate (Qmax) of ≤ 15 mL/s associated with a detrusor pressure at Qmax (PdetQ max) of ≤ 20 cmH2O, along with bladder outlet obstruction (BOO), which was defined as a Qmax of ≤ 15 mL/s with a PdetQ max of > 20 cmH2O. Clinical and urodynamic results were compared between patients with dry and wet symptoms and between those with and without FVD. RESULTS: 78 (47.9%) had dry, and 85 (52.1%) had wet symptoms. The entire group had a relatively low Qmax (15.1 ± 6.6 mL/s) and relatively high number of BOO (42.9%, 70/163) and DUA (8.6%, 14/163). A significantly higher number of patients with wet symptoms had detrusor overactivity compared to those with dry, as detected by the UDS (p < 0.05). No significant differences were found in BOO and DUA number between dry and wet groups. Further, the international prostate symptom score did not different significantly between patients with and without FVD. CONCLUSION: A significant number of women with OAB had voiding dysfunction. However, the OAB symptoms themselves were not useful for predicting the presence of FVD. Therefore, UDS may be necessary for accurate diagnosis in women with OAB symptoms.

Expression of transient receptor potential vanilloid 4 and effects of ruthenium red on detrusor overactivity associated with bladder outlet obstruction in rats.

PURPOSE: To investigate transient receptor potential vanilloid 4 (TRPV4) expression and the effects of ruthenium red (RR)-TRPV antagonist-on detrusor overactivity (DO) associated with bladder outlet obstruction (BOO). METHODS: Rats were randomly assigned to 3 groups. The control group (n = 10) included sham-operated rats. The BOO-group without RR (n = 15) and BOO-group with RR (n = 15) underwent partial BOO surgery. Three weeks postoperatively, cystometrography was performed in all rats. After confirming DO, RR was instilled intravesically in the BOO-group with RR. Urodynamic parameters were investigated, including contraction interval (CI) and contraction pressure (CP). TRPV4 expression was evaluated through immunofluorescence staining and western blotting. RESULTS: The BOO-group without RR had significantly shorter CI and significantly higher CP compared to the control. In the BOO-group with RR, CI was significantly longer compared to the BOO-group without RR. However, change in CP between BOO-group without and with RR was not significantly different. Immunofluorescence staining showed that TRPV4 was localized in the urothelium and detrusor muscles. TRPV4 immunofluorescence signals were increased in the urothelium and detrusor muscle in BOO-group without RR, compared with the control. In western blot analysis, immunoreactive bands indicating expression of TRPV4 were detected in the urothelium and detrusor muscle, and those were significantly increased in the BOO-group without RR compared with the control in the urothelium and detrusor muscle. CONCLUSIONS: TRPV4 plays an important role in the pathophysiology of DO, and RR has a beneficial effect on DO associated with BOO.

Novel pharmacotherapeutic avenues for bladder storage dysfunction in men.

INTRODUCTION: Bladder storage dysfunction is associated with low quality of life in men and remains a challenging field in pharmacotherapy because of low persistence followed by patient-perceived lack of efficacy and adverse effects. The persistent desire for the development of novel pharmacotherapy is evident, leading to numerous research efforts based on its pathophysiology. AREAS COVERED: This review describes the pathophysiology, current pharmacotherapeutic strategies, and emerging novel drugs for male bladder storage dysfunction. The section on emerging pharmacotherapy provides an overview of current research, focusing on high-potential target molecules, particularly those being evaluated in ongoing clinical trials. EXPERT OPINION: As pharmacotherapies targeting alpha-adrenergic, beta-adrenergic, and muscarinic receptors - the current primary targets for treating male bladder storage dysfunction - have demonstrated insufficient efficacy and side effects, researchers are exploring various alternative molecular targets. Numerous targets have been identified as central to regulating bladder afferent nerve activity, and their pharmacological effects and potential have been evaluated in animal-based experiments. However, there is a limited number of clinical trials for these new pharmacotherapies, and they have not demonstrated clear superiority over current treatments. Further research is needed to develop new effective pharmacotherapies for bladder storage dysfunction in men.

Sexual Dimorphism of Spinal Neural Circuits Controlling the Mouse External Urethral Sphincter With and Without Spinal Cord Injury.

Spinal cord injury (SCI) disrupts coordination between the bladder and the external urinary sphincter (EUS), leading to transient or permanent voiding impairment, which is more severe in males. Male versus female differences in spinal circuits related to the EUS as well as post-SCI rewiring are essential for understanding of sex-/gender-specific impairments and possible recovery mechanisms. To quantitatively assess differences between EUS circuits in males versus females and in spinal intact (SI) versus SCI animals, we retrogradely traced and counted EUS-related neurons. In transgenic ChAT-GFP mice, motoneurons (MNs), interneurons (INs), and propriospinal neurons (PPNs) were retrogradely trans-synaptically traced with PRV614-red fluorescent protein (RFP) injected into EUS. EUS-MNs in dorsolateral nucleus (DLN) were separated from other GFP+ MNs by tracing them with FluoroGold (FG). We found two morphologically distinct cell types in DLN: FG+ spindle-shaped bipolar (SB-MNs) and FG- rounded multipolar (RM-MNs) cholinergic cells. Number of MNs of both types in males was twice as large as in females. SCI caused a partial loss of MNs in all spinal nuclei. After SCI, males showed a fourfold rise in the number of RFP-labeled cells in retro-DLN (RDLN) innervating hind limbs. This suggests (a) an existence of direct synaptic interactions between spinal nuclei and (b) a post-SCI increase of non-specific inputs to EUS-MNs from other motor nuclei. Number of INs and PPNs deferred between males and females: In SI males, the numbers of INs and PPNs were ∼10 times larger than in SI females. SCI caused a twofold decrease of INs and PPNs in males but not in females.

Pathophysiology of Overactive Bladder and Pharmacologic Treatments Including ß3-Adrenoceptor Agonists -Basic Research Perspectives.

Overactive bladder (OAB) is a symptom-based syndrome defined by urinary urgency, frequency, and nocturia with or without urge incontinence. The causative pathology is diverse; including bladder outlet obstruction (BOO), bladder ischemia, aging, metabolic syndrome, psychological stress, affective disorder, urinary microbiome, localized and systemic inflammatory responses, etc. Several hypotheses have been suggested as mechanisms of OAB generation; among them, neurogenic, myogenic, and urothelial mechanisms are well-known hypotheses. Also, a series of local signals called autonomous myogenic contraction, micromotion, or afferent noises, which can occur during bladder filling, may be induced by the leak of acetylcholine (ACh) or urothelial release of adenosine triphosphate (ATP). They can be transmitted to the central nervous system through afferent fibers to trigger coordinated urgency-related detrusor contractions. Antimuscarinics, commonly known to induce smooth muscle relaxation by competitive blockage of muscarinic receptors in the parasympathetic postganglionic nerve, have a minimal effect on detrusor contraction within therapeutic doses. In fact, they have a predominant role in preventing signals in the afferent nerve transmission process. ß3-adrenergic receptor (AR) agonists inhibit afferent signals by predominant inhibition of mechanosensitive Aδ-fibers in the normal bladder. However, in pathologic conditions such as spinal cord injury, it seems to inhibit capsaicin-sensitive C-fibers. Particularly, mirabegron, a ß3-agonist, prevents ACh release in the BOO-induced detrusor overactivity model by parasympathetic prejunctional mechanisms. A recent study also revealed that vibegron may have 2 mechanisms of action: inhibition of ACh from cholinergic efferent nerves in the detrusor and afferent inhibition via urothelial ß3-AR.

Changes in urinary nerve growth factor and prostaglandin E2 in women with overactive bladder after anticholinergics.

INTRODUCTION AND HYPOTHESIS: The aim of this study is to investigate changes in urinary nerve growth factor (NGF) and prostaglandin E(2) (PGE(2)) in women with overactive bladder (OAB) following anticholinergic treatment. METHODS: A total of 30 female patients with OAB were enrolled and the control group included 15 healthy women who did not present any bladder symptoms. All subjects with OAB recorded voiding diaries, underwent urodynamic study, and were evaluated for urgency grade. They received anticholinergic treatment for 4 weeks, after which they were again evaluated for urinary urgency grade and voiding diaries. OAB patients were classified into three groups according to the change on the 5-point Urinary Sensation Scale after the treatment: group 1 (no change in urgency grade), group 2 (1 point of improvement), and, group 3 (more than 2 points of improvement). Urinary NGF and PGE(2) levels between controls and OAB patients (before and after treatment in groups 1, 2, and 3) were compared. RESULTS: Urinary NGF and PGE(2) levels were significantly higher in OAB patients than in the controls. NGF levels were not significantly different between pre- and post-treatment in groups 1 and 2. However, in group 3, NGF levels were significantly decreased after treatment. PGE(2) levels were not significantly different between pre- and post-treatment in either group. CONCLUSIONS: NGF and PGE(2) have important roles in the development of OAB symptoms in women. Initial reduction of urgency severity after anticholinergic treatment in women with OAB could be associated with decreasing urinary NGF levels.

Biomarkers for lower urinary tract dysfunction.

Lower urinary tract dysfunction is highly prevalent, but has relatively low persistence and compliance with therapy because of poor efficacy. Although urodynamic study is the gold standard for detailed evaluation of lower urinary tract dysfunction, urodynamic study has limitations as a biomarker, such as invasiveness and a lack of reproducibility of symptoms. Thus, many investigations about new biomarkers for lower urinary tract dysfunction have been carried out and reported. For imaging biomarkers, bladder and prostate parameters assessed by ultrasonography have been used to evaluate lower urinary tract dysfunction. For urinary biomarkers, neurotrophins, such as nerve growth factor and brain derived neurotrophics factor, prostaglandins and cytokines, have been analyzed and evaluated. Among these, nerve growth factor is considered one of the key factors in the pathophysiology of lower urinary tract dysfunction, and is researched in various ways. Serum markers have suggested that C-reactive protein and sex hormones have a relationship with lower urinary tract dysfunction. The possibility of genetic biomarkers in lower urinary tract dysfunction has also been raised. Nevertheless, as yet these biomarkers have not shown enough evidence to reflect lower urinary tract dysfunction and require further investigation. This review will discuss promising and potential biomarkers in lower urinary tract dysfunction to date.

Intravesical Contrast-Enhanced MRI: A Potential Tool for Bladder Cancer Surveillance and Staging.

This review article gives an overview of the current state of the art of bladder cancer imaging and then discusses in depth the scientific and technical merit of a novel imaging approach, tracing its evolution from murine cancer models to cancer patients. While the poor resolution of soft tissue obtained by widely available imaging options such as abdominal sonography and radiation-based CT leaves them only suitable for measuring the gross tumor volume and bladder wall thickening, dynamic contrast-enhanced magnetic resolution imaging (DCE MRI) is demonstrably superior in resolving muscle invasion. However, major barriers still exist in its adoption. Instead of injection for DCE-MRI, intravesical contrast-enhanced MRI (ICE-MRI) instills Gadolinium chelate (Gadobutrol) together with trace amounts of superparamagnetic agents for measurement of tumor volume, depth, and aggressiveness. ICE-MRI leverages leaky tight junctions to accelerate passive paracellular diffusion of Gadobutrol (604.71 Daltons) by treading the paracellular ingress pathway of fluorescein sodium and of mitomycin (<400 Daltons) into bladder tumor. The soaring cost of diagnosis and care of bladder cancer could be mitigated by reducing the use of expensive operating room resources with a potential non-surgical imaging option for cancer surveillance, thereby reducing over-diagnosis and over-treatment and increasing organ preservation.

Outcomes of Artificial Urinary Sphincter Implantation in Patients with Detrusor Underactivity and Postprostatectomy Incontinence.

PURPOSE: There is insufficient evidence for postoperative outcomes of artificial urinary sphincter (AUS) implantation for postprostatectomy incontinence (PPI) with detrusor underactivity (DU). Thus, we assessed the impact of preoperative DU on the outcomes of AUS implantation for PPI. MATERIALS AND METHODS: Medical records of men who underwent AUS implantation for PPI were reviewed. Patients who had bladder outlet obstruction surgery before radical prostatectomy or AUS-related complications that required revision of AUS within three months were excluded. Patients were divided into two groups based on the preoperative urodynamic study including pressure flow study, a DU group, and a non-DU group. DU was defined as a bladder contractility index less than 100. The primary outcome was postoperative postvoid residual urine volume (PVR). The secondary outcomes included maximum flow rate (Qmax), postoperative satisfaction, and international prostate symptom score (IPSS). RESULTS: A total of 78 patients with PPI were assessed. The DU group consisted of 55 patients (70.5%) and the non-DU group comprised 23 patients (29.5%). Qmax was lower in the DU group than in the non-DU group and PVR was higher in the DU group as per a urodynamic study before AUS implantation. There was no significant difference in postoperative PVR between the two groups, although the Qmax after AUS implantation was significantly lower in the DU group. While the DU group showed significant improvements in Qmax, PVR, IPSS total score, IPSS storage subscore, and IPSS quality of life (QoL) score after AUS implantation, the non-DU group showed postoperative improvement in IPSS QoL score. CONCLUSION: There was no clinically significant impact of preoperative DU on the outcome of AUS implantation for PPI; thus, surgery can be safely performed in patients with PPI and DU.

Treating Lower Urinary Tract Symptoms in Older Adults: Intravesical Options.

This article provides an overview of the diagnosis and the treatment of lower urinary tract symptoms in older adults complicated by the neurodegenerative changes in the micturition reflex and further confounded by age-related decline in hepatic and renal clearance raising the propensity of adverse drug reactions. The first-line drug treatment for lower urinary tract symptoms, orally administered antimuscarinics, fails to reach the equilibrium dissociation constant of muscarinic receptors even at their maximum plasma concentration and tends to evoke a half-maximal response at a muscarinic receptor occupancy of just 0.206% in the bladder with a minimal difference from exocrine glands, which raises the adverse drug reaction risk. On the contrary, intravesical antimuscarinics are instilled at concentrations 1000-fold higher than the oral maximum plasma concentration and the equilibrium dissociation constant erects a downhill concentration gradient that drives passive diffusion and achieves a mucosal concentration around ten-fold lower than the instilled concentration for a long-lasting occupation of muscarinic receptors in mucosa and sensory nerves. A high local concentration of antimuscarinics in the bladder triggers alternative mechanisms of action and is supposed to engage retrograde transport to nerve cell bodies for neuroplastic changes that underlie a long-lasting therapeutic effect, while an intrinsically lower systemic uptake of the intravesical route lowers the muscarinic receptor occupancy of exocrine glands to lower the adverse drug reaction relative to the oral route. Thus, the traditional pharmacokinetics and pharmacodynamics of oral treatment are upended by intravesical antimuscarinics to generate a dramatic improvement (~ 76%) noted in a meta-analysis of studies enrolling children with neurogenic lower urinary tract symptoms on the primary endpoint of maximum cystometric bladder capacity as well as the secondary endpoints of filling compliance and uninhibited detrusor contractions. The therapeutic success of intravesical multidose oxybutynin solution or oxybutynin entrapped in the polymer for sustained release in the pediatric population bodes well for patients with lower urinary tract symptoms at the other extreme of the age spectrum. Though generally used to predict oral drug absorption, Lipinski's rule of five can also explain the ten-fold lower systemic uptake from the bladder of positively charged trospium over oxybutynin, a tertiary amine. Chemodenervation by an intradetrusor injection of onabotulinumtoxinA is merited for patients with idiopathic overactive bladder discontinuing oral treatment because of a lack of efficacy. However, age-related peripheral neurodegeneration potentiates the adverse drug reaction risk of urinary retention that motivates the quest of liquid instillation, delivering larger fraction of onabotulinumtoxinA to the mucosa as opposed to muscle by an intradetrusor injection can also probe the neurogenic and myogenic predominance of idiopathic overactive bladder. Overall, the treatment paradigm of lower urinary tract symptoms in older adults should be tailored to individual's overall health status and the risk tolerance for adverse drug reactions.

The incidence of testicular torsion and testicular salvage rate in Korea over 10 years: A nationwide population-based study.

PURPOSE: We performed a nationwide epidemiological study of testicular torsion using the National Health Insurance System database for the entire male population of Korea. MATERIALS AND METHODS: Age, sex, socioeconomic status, regional information, and diagnostic codes were retrieved from January 2009 to December 2019. To clearly identify the diagnosis of testicular torsion, patients who had not undergone orchiectomy or orchiopexy were excluded from the study. Multivariable logistic regression models were used to analyze the association between demographic characteristics and testicular loss. RESULTS: The overall incidence of testicular torsion in males was 2.02 cases per 100,000 person-years and 6.99 cases per 100,000 person-years in males under 19 years of age. Testicular torsion most commonly occurred either in infancy or adolescence. The total testicular salvage rate was 75.22% and highest in children at 79.91%. The rate of orchiectomy was high in infancy and in the oldest patients. We determined that age distribution was related to the risk of testicular loss. CONCLUSIONS: This study is the first nationwide epidemiological study of testicular torsion, which contains the entire Korean population. Although the testicular salvage rate in Korea was higher compared to other countries, it is necessary to educate males under 19 years of age on the seriousness of acute testicular pain to minimize the possibility of testicular loss.

Changes in transient receptor potential vanilloid 1 and transient receptor potential vanilloid 4 in patients with lower urinary tract dysfunction.

PURPOSE: We investigated the association between transient receptor potential vanilloid (TRPV) expression in human urothelium tissue and lower urinary tract dysfunction (LUTD). MATERIALS AND METHODS: We prospectively enrolled men who planned to undergo surgical treatment for benign prostatic obstruction to analyze TRPV1 and TRPV4 expression in the urothelium using enzyme-linked immunosorbent assay and immunofluorescence staining. Patients were divided into two groups based on urodynamics: the detrusor underactivity (DU) group and the non-DU group. Levels of TRPV1 and TRPV4 were compared between the two groups. We also divided patients into two groups according to degree of subjective urinary urgency symptoms using a 5-point urinary sensation scale and compared the differences in TRPV1 and TRPV4 levels between the two groups. The correlations between urodynamic parameters with TRPV1 or TRPV 4 in all patients were also analyzed. RESULTS: The levels of TRPV1 and TRPV 4 were not significantly different between the DU group (n=10) and the non-DU group (n=11). When we divided the patients according to degree of subjective urgency, the level of TRPV1 was not significantly different between the urgency group (n=10) and the non-urgency group (n =11), but the level of TRPV4 was significantly increased in the urgency group (p=0.029). There was no significant correlation between the level of TRPV1 or TRPV4 and urodynamic parameters in any patients. CONCLUSIONS: TRPV4 could be a useful diagnostic biomarker for patients with LUTD.