Pathophysiology of adult urinary incontinence

Hypoxanthine Induces Signs of Bladder Aging With Voiding Dysfunction and Lower Urinary Tract Remodeling

BACKGROUND

Lower urinary tract syndrome (LUTS) is a group of urinary tract symptoms and signs that can include urinary incontinence. Advancing age is a major risk factor for LUTS; however, the underlying biochemical mechanisms of age-related LUTS remain unknown. Hypoxanthine (HX) is a purine metabolite associated with generation of tissue-damaging reactive oxygen species (ROS). This study tested the hypothesis that exposure of the adult bladder to HX-ROS over time damages key LUT elements, mimicking qualitatively some of the changes observed with aging.

METHODS

Adult 3-month-old female Fischer 344 rats were treated with vehicle or HX (10 mg/kg/day; 3 weeks) administered in drinking water. Targeted purine metabolomics and molecular approaches were used to assess purine metabolites and biomarkers for oxidative stress and cellular damage. Biomechanical approaches assessed LUT structure and measurements of LUT function (using custom-metabolic cages and cystometry) were also employed.

RESULTS

HX exposure increased biomarkers indicative of oxidative stress, pathophysiological ROS production, and depletion of cellular energy with declines in NAD+ levels. Moreover, HX treatment caused bladder remodeling and decreased the intercontraction interval and leak point pressure (surrogate measure to assess stress urinary incontinence).

CONCLUSIONS

These studies provide evidence that in adult rats chronic exposure to HX causes changes in voiding behavior and in bladder structure resembling alterations observed with aging. These results suggest that increased levels of uro-damaging HX were associated with ROS/oxidative stress-associated cellular damage, which may be central to age-associated development of LUTS, opening up potential opportunities for geroscience-guided interventions.

Evaluation of Neuromuscular Morphometry of the Vaginal Wall Using Protein Gene Product 9.5 (Pgp 9.5) and Smooth Muscle α-Actin (Sma) in Patients with Posterior Vaginal Wall Prolapse

Background and Objectives: This study aims to compare the neuromuscular structure of the vagina in women with posterior vaginal wall prolapse with the neuromuscular structure of the vagina in women without prolapse, to determine the difference, and to demonstrate the role of neuromuscular structure in the physiopathology of prolapse. Materials and Methods: In this prospective study, women aged between 40 and 75 years who had not undergone any vaginal surgery and had not undergone any abdominal prolapse surgery were included. Thirty-one women diagnosed with rectocele on examination were included in the study group. Thirty-one patients who underwent vaginal intervention and hysterectomy for reasons other than rectocele (colposcopy, conization, etc.) without anterior or posterior wall prolapse were included in the control group. Biopsy material was obtained from the epithelium of the posterior wall of the vagina, including the fascia that fits the Ap point. Immunohistochemical staining with Protein Gene Product 9.5 and smooth muscle α-actin was performed in the pathology laboratory. The epithelial thickness measurement and smooth muscle density parameters obtained with these immunohistochemical stainings were compared between the two groups. The collected data were analyzed using the SPSS 23 package program. p values less than 0.05 were considered statistically significant. Results: In the control group, muscle thickness and the number of nerves per mm2 of fascia were statistically significantly higher than in the study group (p < 0.05). Conclusions: We found that smooth muscle tissue and the number of nerves per mm2 of fascia were decreased in posterior vaginal wall prolapse compared to the general population. Based on the correlation coefficients, age was the parameter that most affected the degree of prolapse, followed by parity, number of live births, and number of vaginal deliveries.

MR defecography in assessing stress urinary incontinence with or without symptomatic pelvic organ prolapse

PURPOSE

Utilize magnetic resonance defecography (MRD) to analyze the primary pelvic floor dysfunctions in patients with stress urinary incontinence (SUI) associated with pelvic organ prolapse (POP), and in SUI patients with asymptomatic POP.

METHOD

We performed MRD in both SUI and POP subjects. As a primary analysis, the functional MR parameters were compared between the isolated POP and POP combined SUI groups. As a secondary analysis, the functional MR data were compared between the POP combined SUI and the SUI with asymptomatic POP (isolated SUI) groups.

RESULTS

MRD noted the main characteristics of SUI combined moderate or severe POP, including the shorter closed urethra length (1.87 cm vs. 2.50 cm, p < 0.001), more prevalent urethral hypermobility (112.31° vs. 85.67°, p = 0.003), bladder neck funneling (48.28% vs. 20.51%, p = 0.020), lower position of vesicourethral junction (2.11 cm vs. 1.67 cm, p = 0.030), and more severe prolapse of the posterior bladder wall (6.26 cm vs. 4.35 cm, p = 0.008). The isolated SUI patients showed the shortest length of the closed urethra (1.56 cm vs. 1.87 cm, p = 0.029), a larger vesicourethral angle (153.80° vs. 107.58°, p < 0.001), the more positive bladder funneling (84.85% vs. 48.28%, p = 0.002) and a special urethral opening sign (45.45% vs. 3.45%, p < 0.001).

CONCLUSIONS

Patients with SUI accompanying POP primarily exhibit excessive urethral mobility and a shortened urethral closure. SUI patients with asymptomatic POP mainly show dysfunction of the urethra and bladder neck, characterized by the opening of the urethra and bladder neck and a shortened urethral closure.

An Overview of the Effect of Aging on the Female Urethra

Urethral function declines by roughly 15% per decade and profoundly contributes to the pathogenesis of urinary incontinence. Individuals with poor urethral function are more likely to fail surgical management for stress incontinence that focus on improving urethral support. The reduced number of intramuscular nerves and the morphologic changes in muscle and connective tissue collectively impact urethral function as women age. Imaging technologies like MRI and ultrasound have advanced our understanding of these changes. However, substantial knowledge gaps remain. Addressing these gaps can be crucial for developing better prevention and treatment strategies, ultimately enhancing the quality of life for aging women.

The effect of trunk-stabilizing muscle training in women with stress urinary incontinence: A randomized controlled trial

INTRODUCTION

There is little evidence regarding the effect of trunk-stabilizing muscle training on the improvement of stress urinary incontinence (SUI) symptoms.

OBJECTIVE

To investigate the effect of trunk-stabilizing muscle training on transabdominal ultrasonography (TAUS) and clinical urological indices, and on the quality of life (QoL) in women with SUI.

DESIGN

Randomized controlled trial.

SETTING

A university hospital.

PARTICIPANTS

Forty-six women with SUI, ages 20-55 years, were randomly assigned to an experimental (n = 23) and control group (n = 23).

INTERVENTIONS

The experimental group performed trunk-stabilization exercises according to the Sapsford protocol, whereas the control group performed pelvic floor muscle (PFM) exercises for 8 weeks.

MAIN OUTCOME MEASURES

The primary outcome measure was bladder base displacement (BBD), assessed by TAUS during PFM contraction (PFMC), Valsalva, and abdominal curl. The secondary outcome measures were PFM strength, the severity of urinary incontinence (UI), voiding diary, and QoL, assessed by the Modified Oxford Grading System, the severity index, frequency chart, and lower urinary tract symptoms-QoL questionnaire, respectively. All variables were assessed at baseline and after 8 weeks of intervention.

RESULTS

The interaction of group and time was not significant for BBD during PFMC (p = .98), Valsalva (p = .28), abdominal curl (p = .34), and secondary variables (p > .05). The main effect of time was significant in both groups for BBD during PFMC, PFM strength, the severity of UI, voiding diary, and QoL (p < .001), with effect size (d) of 0.30, 0.80, 2.05, 1.07, and 1.03 in the control; and 0.49, 0.52, 1.75, 0.66, and 0.88 in the experimental group, respectively. The main effect of the group was not significant for BBD during PFMC (p = .68), Valsalva (p = .22), abdominal curl (p = .53), and secondary variables (p > .05).

CONCLUSIONS

Trunk-stabilizing muscle training and PFM exercise are equally effective in the improvement of PFM function, UI symptoms, and QoL in women with SUI. Both methods can be used interchangeably by physical therapists.

Potential role of physical labor and cultural views of menstruation in high incidence of pelvic organ prolapse in Nepalese women: a comparative study across the menstrual cycle

Introduction

Pelvic organ prolapse (POP) is a significant health concern for young Nepali women, with potential risk factors including pelvic floor trauma from vaginal delivery and heavy lifting. The prevalence of symptomatic POP (SPOP) among nulliparous women in Nepal is 6%, while the general population of Nepali women aged 15-49 years reports a prevalence of 7%. Surprisingly, the average age of SPOP onset in Nepal is 27 years, challenging the assumption that postmenopausal age and vaginal delivery are the sole risk factors. This study aims to investigate the influence of increased intra-abdominal pressure (IAP) during lifting tasks on pelvic organ descent in Nepali women across different menstrual cycle stages.

Methods

The study included 22 asymptomatic Nepali women aged 18-30 years who regularly engage in heavy lifting. Intra-abdominal pressure was measured intra-vaginally during typical and simulated lifting tasks, which encompassed various scenarios such as ballistic lifting, ramped lifting, and pre-contraction of pelvic floor muscles, as well as coughing, Valsalva maneuver, and pelvic floor contractions. Pelvic floor displacement was recorded using transperineal ultrasound during menstruation, ovulation, and the mid-luteal phase.

Results

Results indicated that pelvic floor displacement was greater during menstruation than ovulation when performing a simulated ballistic lifting task (6.0 ± 1.6 mm vs. 5.1 ± 1.5 mm, p = 0.03, d = 0.6). However, there was no significant difference in pelvic floor displacement during lifting when the pelvic muscles were pre-contracted.

Conclusion

These findings suggest that lifting heavy loads during menstruation may increase the risk of stretching and injuring pelvic floor supportive tissues, potentially contributing to SPOP in young Nepali women. Pre-contracting pelvic floor muscles during lifting tasks may offer a protective effect. Understanding these factors could aid in developing targeted preventive measures and raising awareness about the impact of heavy lifting on pelvic floor health among Nepali women.

Endoscopic implantation of autologous myoblasts for stress urinary incontinence and evaluation of its efficacy in sphincterotomized rabbits

INTRODUCTION

Stress urinary incontinence (SUI) is one of the health problems with more impact on patients' lives. The aim of the present work was to develop a therapy for SUI using tissue engineering by isolation and culture of autologous myoblasts (CAM) followed by endoscopic implantation. We also evaluated the efficacy of this therapy in a rabbit model of incontinence after sphincterotomy.

MATERIALS AND METHODS

We used healthy male New Zealand rabbits. The animals were first bled to obtain platelet-poor plasma (PPP) and biopsied for myoblast isolation. Post-sphincterotomy, they were divided into two groups: the treatment group (including animals that received CAM resuspended in PPP) and the control group (including animals receiving only PPP). The leak-point pressure (LPP) was used to measure continence in both groups at different time points. The results were evaluated with hierarchical linear regression models. Histological evaluation of the rabbits' sphincters was also performed at the end of follow-up.

RESULTS

No statistically significant differences were observed between the baseline LPP values of each group. The post-sphincterotomy values of both groups were below 50% of the baseline value, which was a mandatory condition for incontinence. The post-implantation values of the treatment group were higher than 50% of the baseline value, which led us to assume continence recovery. A statistically significant difference was observed in the LPP values between the two treatment groups (p=0.003). Histological study revealed interconnected islands formed by muscle fibers in the treatment group, and connective tissue surrounding the urethral lumen and inflammatory infiltrate in the control group.

DISCUSSION AND CONCLUSIONS

The implantation of CAM significantly improved LPP values in the treatment group, and the improvement remained throughout the evaluation period. It may be associated with the consistency of the implant and its stability at the injection site. Longer follow-up studies and human clinical investigations are required to consider CAM implantation as an alternative treatment for stress urinary incontinence.

Stress Urinary Incontinence: An Unsolved Clinical Challenge

Stress urinary incontinence is still a frequent problem for women and men, which leads to pronounced impairment of the quality of life and withdrawal from the social environment. Modern diagnostics and therapy improved the situation for individuals affected. But there are still limits, including the correct diagnosis of incontinence and its pathophysiology, as well as the therapeutic algorithms. In most cases, patients are treated with a first-line regimen of drugs, possibly in combination with specific exercises and electrophysiological stimulation. When conservative options are exhausted, minimally invasive surgical therapies are indicated. However, standard surgeries, especially the application of implants, do not pursue any causal therapy. Non-absorbable meshes and ligaments have fallen into disrepute due to complications. In numerous countries, classic techniques such as colposuspension have been revived to avoid implants. Except for tapes in the treatment of stress urinary incontinence in women, the literature on randomized controlled studies is insufficient. This review provides an update on pharmacological and surgical treatment options for stress urinary incontinence; it highlights limitations and formulates wishes for the future from a clinical perspective.

Complications and Functional Outcome Differences in Carbon Ion Radiotherapy and Surgery for Malignant Bone Tumors of the Pelvis: A Multicenter, Cohort Study

BACKGROUND

Carbon ion radiotherapy (CIRT) is an evolving treatment option for malignant pelvic tumors in patients with poor surgical indications. However, the difference in complications and functional outcomes between CIRT and surgery is poorly understood. This study compares the complications and functional outcomes of CIRT and surgery to facilitate treatment selection.

METHODS

A total of 28 patients who underwent CIRT for pelvic bone tumors while theoretically meeting the surgical resection criteria were included. Sixty-nine patients who underwent surgery for pelvic bone tumors were included as controls. Major complication rates and functional outcomes (ambulatory, pain, urination, constipation) were evaluated and compared at several time points (pretreatment, discharge, and final follow-up) between the groups.

RESULTS

Early (within 90 days) major complications were not observed in the CIRT group but occurred in 30% of the surgery group, which was statistically significant (P < 0.001). In contrast, late (after 90 days) major complications occurred more often in the CIRT group than in the surgery group (18% and 4%, respectively; P = 0.042). From pretreatment until discharge, all functional outcomes in the surgery group deteriorated (P < 0.001 for all) but did not change in the CIRT group (P = 0.77-1.00). At the final follow-up, all functional outcomes showed no significant intergroup difference (P = 0.28-0.92) due to the recovery trend in the surgery group and the deterioration trend in the CIRT group.

CONCLUSIONS

Compared with surgery, CIRT may have favorable safety and stable functional outcomes in the short-term but more late complications. Mid-term functional outcomes were similar between the groups.

Advances in the molecular pathogenesis and cell therapy of stress urinary incontinence

Stress urinary incontinence (SUI) is very common in women. It affects patients' mental and physical health, and imposed huge socioeconomic pressure. The therapeutic effect of conservative treatment is limited, and depends heavily on patient persistence and compliance. Surgical treatment often brings procedure-related adverse complications and higher costs for patients. Therefore, it is necessary to better understand the potential molecular mechanisms underlying stress urinary incontinence and develop new treatment methods. Although some progress has been made in the basic research in recent years, the specific molecular pathogenic mechanisms of SUI are still unclear. Here, we reviewed the published studies on the molecular mechanisms associated with nerves, urethral muscles, periurethral connective tissue and hormones in the pathogenesis of SUI. In addition, we provide an update on the recent progresses in research on the use of cell therapy for treating SUI, including research on stem cells therapy, exosome differentiation and gene regulation.

A uro-protective agent with restorative actions on urethral and striated muscle morphology

PURPOSE

Aging increases oxidative stress, which can have delirious effects on smooth and striated muscle resulting in bladder dysfunction. Consequently, in women aged over 60 years, urinary incontinence (UI) is a prevalent health problem. Despite the prevalence and consequences, UI continues to be undertreated simply because there are few therapeutic options.

METHODS

Here we investigated whether 8-aminoguanine (8-AG), a purine nucleoside phosphorylase (PNPase inhibitor), would restore urethra and external sphincter (EUS) muscle morphology in the aged rat. Aged (> 25 months) female Fischer 344 rats were randomized to oral treatment with 8-AG (6 weeks) or placebo, and the urethra and EUS were evaluated by electron microscopy and protein expression (western immunoblotting).

RESULTS

Aging was associated with mitochondrial degeneration in smooth and striated muscle cells as compared to young rats. We also observed a significant increase in biomarkers such as PARP, a downstream activator of oxidative/nitrosative stress. Treatment of aged rats with 8-AG normalized all abnormalities to that of a younger state.

CONCLUSIONS

8-AG, a potent inhibitor of PNPase, reverses age-related lower urinary tract morphological and biochemical changes. Our observations support the concept that 8-AG will reverse age-induced lower urinary tract disorders such as UI. These initial findings could have therapeutic implications for the prevention and treatment of age-related UI.

Role of Ano1 Ca2+-activated Cl- channels in generating urethral tone

Urinary continence is maintained in the lower urinary tract by the contracture of urethral sphincters, including smooth muscle of the internal urethral sphincter. These contractions occlude the urethral lumen, preventing urine leakage from the bladder to the exterior. Over the past 20 years, research on the ionic conductances that contribute to urethral smooth muscle contractility has greatly accelerated. A debate has emerged over the role of interstitial cell of Cajal (ICC)-like cells in the urethra and their expression of Ca²⁺-activated Cl^- channels encoded by anoctamin-1 [Ano1; transmembrane member 16 A (Tmem16a) gene]. It has been proposed that Ano1 channels expressed in urethral ICC serve as a source of depolarization for smooth muscle cells, increasing their excitability and contributing to tone. Although a clear role for Ano1 channels expressed in ICC is evident in other smooth muscle organs, such as the gastrointestinal tract, the role of these channels in the urethra is unclear, owing to differences in the species (rabbit, rat, guinea pig, sheep, and mouse) examined and experimental approaches by different groups. The importance of clarifying this situation is evident as effective targeting of Ano1 channels may lead to new treatments for urinary incontinence. In this review, we summarize the key findings from different species on the role of ICC and Ano1 channels in urethral contractility. Finally, we outline proposals for clarifying this controversial and important topic by addressing how cell-specific optogenetic and inducible cell-specific genetic deletion strategies coupled with advances in Ano1 channel pharmacology may clarify this area in future studies.NEW & NOTEWORTHY Studies from the rabbit have shown that anoctamin-1 (Ano1) channels expressed in urethral interstitial cells of Cajal (ICC) serve as a source of depolarization for smooth muscle cells, increasing excitability and tone. However, the role of urethral Ano1 channels is unclear, owing to differences in the species examined and experimental approaches. We summarize findings from different species on the role of urethral ICC and Ano1 channels in urethral contractility and outline proposals for clarifying this topic using cell-specific optogenetic approaches.

The Reliability of Pelvic Floor Muscle Bioelectrical Activity (sEMG) Assessment Using a Multi-Activity Measurement Protocol in Young Women

The aim of the study was to determine the between-trial and between-day reliability of the Glazer protocol and our multi-activity surface electromyography (sEMG) measurement protocol for pelvic floor muscle (PFM) evaluation. The bioelectrical activity of PFM was collected using an endovaginal electrode in 30 young, Caucasian, nulliparous women (age 22–27, 168.6 ± 5.1 cm, 57.1 ± 11.8 kg). The between-trial and between-day reliability of the original Glazer protocol and the new multi-activity sEMG protocol were assessed during the following phases: pre-baseline rest, phasic (flick) contractions, tonic contractions, endurance contraction, and post-baseline rest. The Glazer protocol was characterized by poor and moderate measurement reliability. The time-domain parameters for the rise and fall of the signal amplitude and median frequency showed poor between-trial and between-day reliability. The mean and peak amplitudes indicated mainly good between-trial and moderate between-days reliability. Our protocol showed moderate to excellent reliability of both time-domain and quantitative parameters of muscle recruitment. In our protocol, the frequency-domain parameters describing muscle fatigue demonstrated much higher reliability than in the case of the Glazer protocol. The most important information obtained in this study was the significant improvement of diagnostic validity in PFM bioelectrical activity evaluation. The higher reliability of our sEMG protocol compared to original Glazer protocol allowed us to suggest that protocol modifications and changes in sEMG signal processing methods were effective in the improvement of PFM assessment quality. The new parameters calculated from the sEMG signal proposed in our sEMG protocol allowed us to obtain additional clinically important information about PFM dysfunctions regarding specific deficits of muscle contraction such as decrease in muscle strength; endurance or coordination related to, e.g., stress urinary incontinence; or pelvic floor muscle imbalance after childbirth.

Bladder and bowel preferences of patients at the end of life: a scoping review

BACKGROUND

Following patient preferences at the end of life should improve outcomes of care, yet patient preferences regarding bladder and bowel care are not often accommodated, as they are not well known in the literature.

AIMS

This scoping review sought to identify bladder and bowel care preferences of patients at the end of life in published literature.

METHODS

Papers published in or after 1997 (in English) that focused on adult preferences for bladder and bowel care at the end of life were included.

FINDINGS

Scant literature exists on preferences for bladder and bowel care for adult patients at end of life. Further investigation is warranted to arrive at a better understanding of preferences regarding bladder and bowel symptom management.

CONCLUSIONS

Future research should explore if prioritising the symptoms caused by incontinence, among the many symptoms experienced at the end of life, could be achieved through careful questioning and development of a standardised tool focused on improving patient care and incorporating patient preferences for care.

Association between elastography findings of the levator ani and stress urinary incontinence

PURPOSE

To investigate the elasticity of the levator ani musle (LAM) with the patients suffering from stress urinary incontinence (SUI) by transperineal elastography.

METHODS

Conventional transperineal ultrasound and elastography were performed in the patients with SUI on quiescent condition and maximal Valsalva. Transperineal ultrasound and elastography were repeated after Kegel exercises. The scoring system and strain ratio (SR) values were recorded and analyzed.

RESULTS

After Kegel exercises, the ratio of subjective improvement or cure was 81 % (102/126). Mean elasticity score (ES) and SR of LAM were significantly higher than the value before on maximal Valsalva, respectively. Mean ES and SR of LAM after Kegel exercises were similar with the value before on quiescent condition, respectively.

CONCLUSION

The improvement of SUI was associated with the stiffer LAM assessed by elastography. Women with SUI who have softer LAM were more likely to have symptoms of SUI and Kegel exercise could strengthen the stiffness of LAM.

BRIEF SUMMARY

The improvement of SUI was associated with the stiffer LAM assessed by elastography.

Novel insight into pressurization of the male and female urethra through application of a multi-channel fibre-optic pressure transducer: Proof of concept and validation

Purpose

To confirm feasibility of recording pressure along the length of the urethra using a multi-sensor fibre-optic pressure catheter; to identify the spatial and temporal features of changes in pressure along the urethra at sites related to specific striated pelvic floor muscles; and to investigate the relationship between urethral pressures and activation of individual pelvic floor muscles estimated from ultrasound imaging.

Materials and Methods

Proof-of-concept study including one male (47 years old) and one female (33 years old). A multi-sensor fibre optic pressure catheter (10 mm sensor separation) was inserted into the urethra. Pressure data were recorded simultaneously with trans-perineal ultrasound imaging measures of pelvic floor muscle activity during sub-maximal and maximal voluntary contractions and evoked coughs.

Results

Pressure changes along the urethra were recorded in all tasks in both participants. Face validity of interpretation of pressure measures with respect to individual muscles was supported by correlation with ultrasound-measured displacements induced by the relevant muscles. Onset of pressure increase occurred in a distal to proximal sequence in the urethra of the male but not the female during voluntary contraction. Peak urethral pressures varied in location, timing and amplitude between tasks. Evoked cough induced in the greatest urethral pressure increase across all tasks for both participants.

Conclusions

The high spatial resolution pressure catheter provide viable and valid recordings of urethral pressure in a male and female. Data provide preliminary evidence of sex differences in spatial and temporal distribution of urethral pressure changes.

Development of a wireless accelerometer-based Intravaginal device to detect pelvic floor motion for evaluation of pelvic floor dysfunction

Urinary incontinence (UI) is experienced by an estimated 51% of women in the U.S. and often results from impaired function or weakening of the pelvic floor muscles. Pelvic floor muscle training (PFMT) is a frontline nonsurgical treatment, yet a number of symptomatic individuals cannot accurately perform a pelvic floor muscle contraction with simple verbal or written instruction. Long-term adherence to PFMT regimens is often a barrier to resolution of symptoms. Various biofeedback tools have been utilized to aid correct pelvic floor muscle performance and adherence. One novel device, the leva® Pelvic Digital Health System, utilizes an intravaginal probe embedded with MEMS accelerometer sensors that allow real-time visualization of the shape and motion of the vagina during PFMT. Early positive results with this device prompted design of a wearable version. The purpose of this study was to design a wearable, wireless clinical research device to optimize MEMS accelerometer sensor placement to detect maximal movement during a pelvic floor muscle exercise (PFME) and to test the form factor for retention and user acceptability. The device comprised a ring designed to sit at the fornix with an extension following the length of the vagina. This paper presents design components and results from clinical testing of 10 subjects. It was determined that a ring form factor alone, similar to other vaginal rings (pessaries, estrogen rings) provided less accurate visual information about PFME performance. By contrast, we determined that a ring with an extension allowed for device retention and improved real-time detection of vaginal shape and motion during PFMT.

A computational analysis of the effect of supporting organs on predicted vesical pressure in stress urinary incontinence

Stress urinary incontinence (SUI) or urine leakage from urethra occurs due to an increase in abdominal pressure resulting from stress like a cough or jumping height. SUI is more frequent among post-menopausal women. In the absence of bladder contraction, vesical pressure exceeds urethral pressure leading to urine leakage. The main aim of this study is to utilize fluid-structure interaction techniques to model bladder and urethra computationally under an external pressure like sneezing. Both models have been developed with linear elastic properties for the bladder wall while the patient model has also been simulated utilizing the Mooney-Rivlin solid model. The results show a good agreement between the clinical data and the predicted values of the computational models, specifically the pressure at the center of the bladder. There is 1.3% difference between the predicted vesical pressure and the vesical pressure obtained from urodynamic tests. It can be concluded that the accuracy of the predicted pressure in the center of the bladder is significantly higher for the simulation assuming nonlinear material property (hyperelastic) for the bladder in comparison to the accuracy of the linear elastic model. The model is beneficial for exploring treatment solutions for SUI disorder. Graphical abstract ^{3D processing of bladder deformation during abdominal pressure of a the physiological model and b the pathological model (starting from left to right and up to down, consecutively)}.

Contribution of Cav1.2 Ca2+ channels and store-operated Ca2+ entry to pig urethral smooth muscle contraction

Urethral smooth muscle (USM) generates tone to prevent urine leakage from the bladder during filling. USM tone has been thought to be a voltage-dependent process, relying on Ca²⁺ influx via voltage-dependent Ca²⁺ channels in USM cells, modulated by the activation of Ca²⁺-activated Cl^- channels encoded by Ano1. However, recent findings in the mouse have suggested that USM tone is voltage independent, relying on Ca²⁺ influx through Orai channels via store-operated Ca²⁺ entry (SOCE). We explored if this pathway also occurred in the pig using isometric tension recordings of USM tone. Pig USM strips generated myogenic tone, which was nearly abolished by the Ca_v1.2 channel antagonist nifedipine and the ATP-dependent K⁺ channel agonist pinacidil. Pig USM tone was reduced by the Orai channel blocker GSK-7975A. Electrical field stimulation (EFS) led to phentolamine-sensitive contractions of USM strips. Contractions of pig USM were also induced by phenylephrine. Phenylephrine-evoked and EFS-evoked contractions of pig USM were reduced by ~50-75% by nifedipine and ~30% by GSK-7975A. Inhibition of Ano1 channels had no effect on tone or EFS-evoked contractions of pig USM. In conclusion, unlike the mouse, pig USM exhibited voltage-dependent tone and agonist/EFS-evoked contractions. Whereas SOCE plays a role in generating tone and agonist/neural-evoked contractions in both species, this dominates in the mouse. Tone and agonist/EFS-evoked contractions of pig USM are the result of Ca²⁺ influx primarily through Ca_v1.2 channels, and no evidence was found supporting a role of Ano1 channels in modulating these mechanisms.

A structured review on the female urethral anatomy and innervation with an emphasis on the role of the urethral longitudinal smooth muscle

A damaged sphincteric unit or support system, unstable urethral deformability or damaged sensory innervation are all potential causes of a dysfunctional urethral sphincter. With the current improvement in pharmacological targets and urodynamic understanding, studies have begun quantifying individual structures and their importance in closure pressure and consequently urethral continence. However, when it comes to the function of the longitudinal urethral smooth muscle layer, there is currently no consensus. The intent of this structured review is to critically examine literature regarding the female urethral anatomy and closure mechanism. We hypothesized that the longitudinal smooth muscle is a prerequisite for sufficient urethral closure and not merely involved during micturition. Overall opinions on a dysfunctional closure mechanism are controversial. Nonetheless, basic mechanics may be applied to understand simple urodynamics. With the assumption of longitudinal muscles forming a plug when contracted, this could have a substantial effect on the continence mechanism.

Multiple doses of stem cells maintain urethral function in a model of neuromuscular injury resulting in stress urinary incontinence

Stress urinary incontinence (SUI) is more prevalent among women who deliver vaginally than women who have had a cesarean section, suggesting that tissue repair after vaginal delivery is insufficient. A single dose of mesenchymal stem cells (MSCs) has been shown to partially restore urethral function in a model of SUI. The aim of the present study was to determine if increasing the number of doses of MSCs improves urethral and pudendal nerve function and anatomy. We hypothesized that increasing the number of MSC doses would accelerate recovery from SUI compared with vehicle treatment. Rats underwent pudendal nerve crush and vaginal distension or a sham injury and were treated intravenously with vehicle or one, two, or three doses of 2 × 10⁶ MSCs at 1 h, 7 days, and 14 days after injury. Urethral leak point pressure testing with simultaneous external urethral sphincter electromyography and pudendal nerve electroneurography were performed 21 days after injury, and the urethrovaginal complex and pudendal nerve were harvested for semiquantitative morphometry of the external urethral sphincter, urethral elastin, and pudendal nerve. Two and three doses of MSCs significantly improved peak pressure; however, a single dose of MSCs did not. Single, as well as repeated, MSC doses improved urethral integrity by restoring urethral connective tissue composition and neuromuscular structures. MSC treatment improved elastogenesis, prevented disruption of the external urethral sphincter, and enhanced pudendal nerve morphology. These results suggest that MSC therapy for postpartum incontinence and SUI can be enhanced with multiple doses.

Effect of Weight Training with Pelvic Floor Muscle Training in Elderly Women with Urinary Incontinence

PURPOSE

To determine if weight training combined with pelvic floor muscle training is more efficient than pelvic floor muscle training alone for the treatment of urinary incontinence (UI) symptoms in elderly women.

METHOD

This was a two-arm, parallel, randomized controlled trial. Twenty-six women with stress UI participated in the study. The intervention group (IG) underwent training with moderate intensity weights combined with pelvic floor muscle training, whereas the control group (CG) only underwent pelvic floor muscle training. Intervention occurred twice a week over 12 weeks. The International Consultation on Incontinence Questionnaire-Short Form was used as the main measure. Scores of zero defined the absence of symptoms. The absence of symptoms was evaluated at 4 weeks, 12 weeks, and 1 month after the end of treatment. Moreover, activities related to UI and the use and change of daily protection were investigated.

RESULTS

The rate of absence of symptoms was significantly higher in IG after 4 weeks (58.3%) compared to CG (14.8%). The relative risk was 4.1 (95% confidence interval [CI] [1.08, 16.06]). Although no intention-to-treat analysis was performed, there was no difference in the evaluations after the interventions.

CONCLUSION

Compared to pelvic floor muscle training alone, the combination of weight training and pelvic floor muscle training provided earlier improvement of UI in elderly women.

Long-term effects of motherfit group therapy in pre-(MOTHERFIT1) and post-partum women (MOTHERFIT2) with stress urinary incontinence compared to care-as-usual: study protocol of two multi-centred, randomised controlled trials

Background

Stress urinary incontinence (SUI) is highly prevalent during pregnancy and after delivery. It is often associated with a failing pelvic floor, sphincteric and/or supportive system. Pelvic-floor-muscle training (PFMT) peri-partum has been proven effective for up to 1 year post-partum; however, its long-term effects are unknown. Group PFMT, given by a physiotherapist, has been proven to be as equally effective as individual therapy. Motherfit is a group-PFMT therapy with an emphasis on pelvic floor exercises, adherence and general fitness. Care-as-usual (CAU), if guideline driven, should, as first treatment option, consist of PFMT. Cost-effective strategies are of relevance, given the rise of health care costs. Motherfit group therapy has the potential to be cost-effective in women with urinary incontinence. Therefore, the objectives of the two current studies are: (1) to investigate whether intensive, supervised, pre-partum (MOTHERFIT1) or post-partum (MOTHERFIT2) pelvic-floor-muscle group therapy reduces 18-month post-partum severity of SUI compared to CAU and (2) whether MOTHERFIT1 OR MOTHERFIT 2 is more (cost-)effective compared to CAU.

Methods

Two multi-centred, randomised controlled trials (MOTHERFIT1, n = 150, MOTHERFIT2, n = 90) will be performed. Participants will be recruited by their midwife or gynaecologist during their routine check. Participants with SUI will receive either motherfit group therapy or CAU. Motherfit group therapy consists of eight group sessions of 60 min each, instructed and supervised by a registered pelvic physiotherapist. Motherfit group therapy includes instructions on pelvic floor anatomy and how to contract, relax and train the pelvic-floor muscles correctly and is combined with general physical exercises. Adherence during and after motherfit will be stimulated by reinforcement techniques and a mobile app. The primary outcome measure is the absence of self-reported SUI based on the severity sum score of the International Consultation on Incontinence Questionnaire Short Form (ICIQ-UI-SF) at 18 months post-partum. Secondary outcomes evaluate quality of life, subjective improvement and health care costs.

Discussion

The motherfit studies are, to our knowledge, the first studies that evaluate both long-term results and health care costs compared to CAU in pregnant and post-partum women with SUI. If motherfit is shown to be (cost-)effective, implementation in peri-partum care should be considered.

Trial registration

Netherlands Trial Register, ID: NL5816. Registered on 18 July 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3331-6) contains supplementary material, which is available to authorized users.

Effect of ASP2205 fumarate, a novel 5-HT2C receptor agonist, on urethral closure function in rats

The pharmacological profile of ASP2205 fumarate (ASP2205), a novel 5-HT_2C receptor agonist, was evaluated in vitro and in vivo. ASP2205 showed potent and selective agonistic activity for the human 5-HT_2C receptor, with an EC₅₀ of 0.85 nM in the intracellular Ca²⁺ mobilization assay. Rat 5-HT_2C receptor was also activated by ASP2205 with an EC₅₀ of 2.5 nM. Intraduodenal administration (i.d.) of ASP2205 (0.1-1 mg/kg) significantly elevated the leak point pressure (LPP) in anesthetized rats in a dose-dependent manner. This ASP2205 (0.3 mg/kg i.d.)-induced LPP elevation was inhibited by SB242084 (0.3 mg/kg i.v.), a selective 5-HT_2C receptor antagonist. Urethral closure responses induced by intravesical pressure loading in rats were enhanced by ASP2205 (0.3 mg/kg i.v.), which was abolished by pretreatment with SB242084 (0.3 mg/kg i.v.) and bilateral transection of the pudendal nerve. In contrast, ASP2205 (0.3 mg/kg i.v.) did not change the resting urethral pressure in rats. These results indicate that ASP2205 can enhance the pudendal nerve-mediated urethral closure reflex via the 5-HT_2C receptor, resulting in the prevention of involuntary urine loss.

Pelvic floor muscle activity during fast voluntary contractions in continent and incontinent women

AIMS

Stress urinary incontinence (SUI) has also been attributed to a lower speed of contraction of the pelvic floor muscles (PFM). Therefore, PFM assessment and training implement fast voluntary contractions (FVC). The purpose of the study was to explore FVC regarding feasibility, on-/offset and rate of activity determination, as well as differences between continent (CON) and stress urinary incontinent (SUI) women.

METHODS

Fifty women were included and examined by means of PFM EMG during rest, maximum voluntary contractions (MVC), and five FVC. MVC-peak activity was used to normalize EMG-data. On-/offset of muscle activity was determined as mean of rectified rest activity plus 1 standard deviation. Linear regression was calculated for rate of activity from onset to peak, peak to offset, and within 200 ms after both onset and peak. Peak activity and time variables related to onset, peak, and offset were calculated.

RESULTS

On-/offsets were evaluable for 234/222 of 250 FVC by a computer-based algorithm, 16/28 on-/offsets had to be determined manually. There was no significant difference between groups (CON/SUI) regarding FVC peak (92.1/99.3 %MVC), time to peak (514.2/525.6 ms), and increase of activity (182.8/182.1 %MVC/s). The SUI group showed a significantly slower activity decrease (-120.7/-74.4 %MVC/s).

CONCLUSIONS

FVC analyses were shown to be feasible. The significant difference observed between the groups did not refer to activity increase but instead to a prolonged relaxation phase in the SUI group. This prompts to reconsider the interpretation of FVC in PFM testing and training.

Age and multiparity related urethral sphincter muscle dysfunction in a rabbit model: Potential roles of TGF-β and Wnt-β catenin signaling pathways

AIMS

Prior studies demonstrate increased incidence of urinary incontinence (UI) in the geriatric population which affects their quality of life. Pathophysiology of UI in the geriatric population and the underlying molecular mechanisms are still unclear. To elucidate these mechanisms, we performed a pre-clinical study in a rabbit model and the objectives were to (i) determine the effect of aging as well as multiparity on urethral sphincter muscle thickness and urethral closing pressure (UCP); (ii) examine the role of fibrosis and atrophy; and (iii) elucidate the molecular pathways that mediate fibrosis and atrophy in the urethral tissue.

METHODS

New Zealand White female rabbits (n = 6 each; young 6-12 months and old over 30 months of age) were anesthetized and urethral muscle thickness and sphincter closure function were measured. Rabbits were then sacrificed and urethral tissues (bladder neck and mid-urethra) were collected to process for immunostaining as well as for molecular studies for markers for fibrosis (β-catenin which is an important mediator of Wnt signaling, Collagen-1, and TGF-β) and atrophy (MuRF-1).

RESULTS

Our studies showed a significant decrease in the urethral sphincter muscle thickness and closure function with age. Age-related increase in protein and mRNA expression levels of fibrosis, as well as atrophy markers were observed in the bladder neck and mid-urethral tissues.

CONCLUSIONS

Age and multiparity related increase in fibrosis and atrophy of urethral sphincter muscles may contribute to impaired urethral closure function seen in old animals.

Laboratory practical to study the differential innervation pathways of urinary tract smooth muscle

In the mammalian lower urinary tract, there is a reciprocal relationship between the contractile state of the bladder and urethra. As the bladder fills with urine, it remains relaxed to accommodate increases in volume, while the urethra remains contracted to prevent leakage of urine from the bladder to the exterior. Disruptions to the normal contractile state of the bladder and urethra can lead to abnormal micturition patterns and urinary incontinence. While both the bladder and urethra are smooth-muscle organs, they are differentially contracted by input from cholinergic and sympathetic nerves, respectively. The laboratory practical described here provides an experiential approach to understanding the anatomy of the lower urinary tract. Several key factors in urinary tract physiology are outlined, e.g., the bladder is contracted by activation of the parasympathetic pathway via cholinergic stimulation on muscarinic receptors, whereas the urethra is contracted by activation of the sympathetic pathway via adrenergic stimulation on α₁-adrenoceptors. This is achieved by measuring the force generated by bladder and urethra smooth muscle to demonstrate that acetylcholine contracts the smooth muscle of the bladder, whereas adrenergic agonists contract the urethral smooth muscle. An inhibition of these effects is also demonstrated by application of the muscarinic receptor antagonist atropine and the α₁-adrenergic receptor blocker phentolamine. A list of suggested techniques and exam questions to evaluate student understanding on this topic is also provided.

UROKIN: A Software to Enhance Our Understanding of Urogenital Motion

Transperineal ultrasound (TPUS) allows for objective quantification of mid-sagittal urogenital mechanics, yet current practice omits dynamic motion information in favor of analyzing only a rest and a peak motion frame. This work details the development of UROKIN, a semi-automated software which calculates kinematic curves of urogenital landmark motion. A proof of concept analysis, performed using UROKIN on TPUS video recorded from 20 women with and 10 women without stress urinary incontinence (SUI) performing maximum voluntary contraction of the pelvic floor muscles. The anorectal angle and bladder neck were tracked while the motion of the pubic symphysis was used to compensate for the error incurred by TPUS probe motion during imaging. Kinematic curves of landmark motion were generated for each video and curves were smoothed, time normalized, and averaged within groups. Kinematic data yielded by the UROKIN software showed statistically significant differences between women with and without SUI in terms of magnitude and timing characteristics of the kinematic curves depicting landmark motion. Results provide insight into the ways in which UROKIN may be useful to study differences in pelvic floor muscle contraction mechanics between women with and without SUI and other pelvic floor disorders. The UROKIN software improves on methods described in the literature and provides unique capacity to further our understanding of urogenital biomechanics.

Clinical Evaluation of Urinary Incontinence

Pelvic organ prolapse is the downward descent of the pelvic floor organs and has a prevalence of 3%–6% and can even reach to 50% if defined by a vaginal examination. The anatomical concepts of pelvic diaphragm, lateral attachment of vagina to arcus tendineus fascia pelvis, and intrinsic and extrinsic sphincter control mechanisms are elaborated. The anatomic and physiological mechanisms of autonomic and voluntary control of continence are discussed. The clinical and urodynamic tests and their implications in guiding the management are explained. Finally, uroflowmetry, cystometry, urethral pressure profile, postvoid urine measurement, leak point pressure (LPP) test, video urodynamic tests, and electromyography studies of pelvic floor are discussed as an integral part of the assessment.

Pelvic floor muscle training protocol for stress urinary incontinence in women: A systematic review

Summary Introduction: Strengthening exercises for pelvic floor muscles (SEPFM) are considered the first approach in the treatment of stress urinary incontinence (SUI). Nevertheless, there is no evidence about training parameters. Objective: To identify the protocol and/or most effective training parameters in the treatment of female SUI. Method: A literature research was conducted in the PubMed, Cochrane Library, PEDro, Web of Science and Lilacs databases, with publishing dates ranging from January 1992 to March 2014. The articles included consisted of English-speaking experimental studies in which SEPFM were compared with placebo treatment (usual or untreated). The sample had a diagnosis of SUI and their age ranged between 18 and 65 years. The assessment of methodological quality was performed based on the PEDro scale. Results: Seven high methodological quality articles were included in this review. The sample consisted of 331 women, mean age 44.4±5.51 years, average duration of urinary loss of 64±5.66 months and severity of SUI ranging from mild to severe. SEPFM programs included different training parameters concerning the PFM. Some studies have applied abdominal training and adjuvant techniques. Urine leakage cure rates varied from 28.6 to 80%, while the strength increase of PFM varied from 15.6 to 161.7%. Conclusion: The most effective training protocol consists of SEPFM by digital palpation combined with biofeedback monitoring and vaginal cones, including 12 week training parameters, and ten repetitions per series in different positions compared with SEPFM alone or a lack of treatment.

Effect of combined actions of hip adduction/abduction on the force generation and maintenance of pelvic floor muscles in healthy women

Pelvic floor muscle (PFM) force and coordination are related to urinary incontinence severity and to sexual satisfaction. Health professionals frequently combine classic PFM exercises with hip adduction/abduction contraction to treat these disorders, but the real benefits of this practice are still unknown. Based on a theoretical anatomy approach whereby the levator ani muscle is inserted into the obturator internus myofascia and in which force generated by hip movements should increase the contraction quality of PFMs, our aim was to investigate the effects of isometric hip adduction and abduction on PFM force generation. Twenty healthy, nulliparous women were evaluated using two strain-gauge dynamometers (one cylinder-like inside the vaginal cavity, and the other measuring hip adduction/abduction forces around both thighs) while performing three different tasks: (a) isolated PFM contraction; (b) PFM contraction combined with hip adduction (30% and 50% maximum hip force); and (c) PFM contraction combined with hip abduction (30% and 50% maximum hip force). Data were sampled at 100Hz and subtracted from the offset if existent. We calculated a gradient between the isolated PFM contraction and each hip condition (Δ Adduction and Δ Abduction) for all variables: Maximum force (N), instant of maximum-force occurrence (s), mean force in an 8-second window (N), and PFM force loss (N.s). We compared both conditions gradients in 30% and 50% by paired t-tests. All variables did not differ between hip conditions both in 30% and 50% of maximum hip force (p>.05). PFM contraction combined with isometric hip abduction did not increase vaginal force in healthy and nulliparous women compared to PFM contraction combined with isometric hip adduction. Therefore, so far, the use of hip adduction or abduction in PFM training and treatments are not justified for improving PFM strength and endurance.

Traditional Gymnastic Exercises for the Pelvic Floor Often Lead to Bladder Neck Descent - a Study Using Perineal Ultrasound

BACKGROUND

The aims of physiotherapy in stress incontinent women are to improve pelvic floor function and the continence mechanism including bladder neck support and urethral closure pressure. In Germany, traditional conservative treatment often includes gymnastic exercises with unclear effects on the bladder neck. The aim of this study was to sonographically assess bladder neck movements during selected exercises.

METHODS

Fifteen healthy, continent women without previous vaginal births, who were able to voluntarily contract their pelvic floor muscels performed the shoulder bridge, the abdominal press, tiptoe and the Pilates clam exercises. The first set was performed without any additional instructions. During the second set directions were given to activate the pelvic floor before beginning each exercise and to maintain the contraction throughout the exercise. Bladder neck movement was measured on perineal ultrasound using a validated method with the pubic symphysis as a reference point.

RESULTS

The median age of participants was 32 years, median BMI was 23. Eight women were nulliparous and seven had given birth to 1 - 2 children via caesarean section. When exercises were performed without voluntary pelvic floor contraction the bladder neck descended on average between 2.3 and 4.4 mm, and with pelvic floor contraction prior to the exercise only between 0.5 and 2.1 mm (p > 0.05 except for abdominal press p = 0.007). The Pilates clam exercise and toe stand stabilised the bladder neck most effectively.

DISCUSSION

Bladder neck descent often occurs during pelvic floor gymnastic exercises as traditionally performed in Germany, and a voluntary pelvic floor contraction during the exercises does not necessarily prevent this.

Experimental investigation of the biomechanics of urethral tissues and structures

NEW FINDINGS

What is the central question of this study? Prostheses for treatment of urinary incontinence elicit complications associated with an inadequate mechanical action. This investigation aimed to define a procedure addressed to urethral mechanical characterization. Experimental tests are the basis for constitutive formulation, with a view to numerical modelling for investigation of the interaction between the tissues and a prosthesis. What is the main finding and its importance? Horse urethra, selected for its histomorphometric similarity to human urethra, was characterized by integrated histological analysis and mechanical tests on the biological tissue and structure, leading to constitutive formulation. A non-linear, anisotropic and time-dependent response was found, representing a valid basis for development of a numerical model to interpret the functional behaviour of the urethra. Urinary dysfunction can lead to incontinence, with an impact on the quality of life. Severe dysfunction can be overcome surgically by the use of an artificial urinary sphincter. Nonetheless, several complications may result from inappropriate functioning of the prosthesis, in many instances resulting from an unsuitable mechanical action of the device on the urethral tissues. Computational models allow investigation of the mechanical interaction between biological tissues and biomedical devices, representing a potential support for surgical practice and prosthesis design. The development of such computational tools requires experimental data on the mechanics of biological tissues and structures, which are rarely reported in the literature. The aim of this study was to provide a procedure for the mechanical characterization of urethral tissues and structures. The experimental protocol included the morphometric and histological analysis of urethral tissues, the mechanical characterization of the response of tissues to tensile and stress-relaxation tests and evaluation of the behaviour of urethral structures by inflation tests. Results from the preliminary experiments were processed, adopting specific model formulations, and also providing the definition of parameters that characterize the elastic and viscous behaviour of the tissues. Different experimental protocols, leading to a comprehensive set of experimental data, allow for a reciprocal assessment of reliability of the investigation approach.

A Novel Method of Urinary Sphincter Deficiency: Serial Histopathology Evaluation in a Rat Model of Urinary Incontinence

In this study, a novel technique of irreversible sphincter deficiency by pudendal nerve transection (PNT) using 40 female rats for studying the pathophysiology of stress urinary incontinence associated with childbirth was developed. Of the 40 rats, 10 served as controls and the remaining underwent bilateral PNT at the anastomotic lumbosacral trunk level. Urethral morphological changes following bilateral PNT were assessed with serial hematoxylin and eosin (H&E) and immunohistochemistry (IHC) staining methods at 50, 90, and 130 days post-intervention. Leak point pressure (LPP) measurement was used to determine the effect of pudendal injury on urethral outlet resistance after the transection. H&E and IHC staining showed irreversible loss of striated muscle mass of the sphincter region and increase in collagen deposition compatible with muscle atrophy. LPP measurements also significantly decreased following bilateral PNT. In conclusion, a novel method of irreversible sphincter insufficiency was developed. This model effectively decreased urethral outlet resistance and caused irreversible striated muscle atrophy. It was suggested that this technique can be used to develop a permanent sphincter deficiency model for the preclinical testing of treatment modalities exclusively triggering the pudendal nerve.

Assessment of urethral vascularity using 2D colour Doppler high-frequency endovaginal ultrasonography in women treated for symptomatic stress urinary incontinence: 1-year prospective follow-up study

INTRODUCTION

Urethral vascularity is responsible for organ perfusion. It is also believed to contribute to maintaining the normal tension in the urethral mucosa and contributes to approximately one third of urethral closure pressure. We hypothesised that in women undergoing treatment for stress urinary incontinence (SUI), there is no change in blood flow intensity.

METHODS

In this pilot study we recruited women attending the urogynaecology clinics between July and October 2009. Exclusion criteria included symptoms of pelvic organ prolapse or urinary tract infection. Colour Doppler ultrasound was performed at the level of the mid-urethra using a high-frequency (9-12 MHz) endovaginal ultrasonography (EVUS) focusing on the following vascular parameters: flow velocity (V), area of the vessels (A), intensity of perfusion (I), Tissue Pulsatility Index (TPI) and Tissue Resistance Index (TRI). Vascular assessments were repeated at 1 year.

RESULTS

We examined 67 women with symptoms of SUI (17 women had surgery and 50 conservative management, i.e., pelvic floor muscle exercises). The mean (± SD) age in the conservative and surgical groups was 46 (±11) and 40 (±9) years respectively and median (range) parity was 2 (0-8) in both groups. Compared to baseline, no statistically significant differences were observed within each group (p > 0.05) or between the values of vascular parameters (V, A, I, TRI and TPI) at 1 year. There was also no difference in vascular parameters between the two groups.

CONCLUSION

At 12 months there is no change in vascularity parameters in women who opt for conservative or surgical treatment of SUI.

Cell Therapy for Stress Urinary Incontinence

Urinary incontinence (UI) is the involuntary loss of urine and is a common condition in middle-aged and elderly women and men. Stress urinary incontinence (SUI) is caused by leakage of urine when coughing, sneezing, laughing, lifting, and exercise, even standing leads to increased intra-abdominal pressure. Other types of UI also exist such as urge incontinence (also called overactive bladder), which is a strong and unexpected sudden urge to urinate, mixed forms of UI that result in symptoms of both urge and stress incontinence, and functional incontinence caused by reduced mobility, cognitive impairment, or neuromuscular limitations that impair mobility or dexterity. However, for many SUI patients, there is significant loss of urethral sphincter muscle due to degeneration of tissue, the strain and trauma of pregnancy and childbirth, or injury acquired during surgery. Hence, for individuals with SUI, a cell-based therapeutic approach to regenerate the sphincter muscle offers the advantage of treating the cause rather than the symptoms. We discuss current clinically relevant cell therapy approaches for regeneration of the external urethral sphincter (striated muscle), internal urethral sphincter (smooth muscle), the neuromuscular synapse, and blood supply. The use of mesenchymal stromal/stem cells is a major step in the right direction, but they may not be enough for regeneration of all components of the urethral sphincter. Inclusion of other cell types or biomaterials may also be necessary to enhance integration and survival of the transplanted cells.

Pattern of activation of pelvic floor muscles in men differs with verbal instructions

AIMS

To investigate the effect of instruction on activation of pelvic floor muscles (PFM) in men as quantified by transperineal ultrasound imaging (US) and to validate these measures with invasive EMG recordings.

METHODS

Displacement of pelvic floor landmarks on transperineal US, intra-abdominal pressure (IAP) recorded with a nasogastric transducer, and surface EMG of the abdominal muscles and anal sphincter were recorded in 15 healthy men during sub-maximal PFM contractions in response to different verbal instructions: "tighten around the anus," "elevate the bladder," "shorten the penis," and "stop the flow of urine." In three men, fine-wire EMG recordings were made from puborectalis and bulbocavernosus, and trans-urethral EMG recordings from the striated urethral sphincter (SUS). Displacement data were validated by analysis of relationship with invasive EMG. Displacement, IAP, and abdominal/anal EMG were compared between instructions.

RESULTS

Displacement of pelvic landmarks correlated with the EMG of the muscles predicted anatomically to affect their locations. Greatest dorsal displacement of the mid-urethra and SUS activity was achieved with the instruction "shorten the penis." Instruction to "elevate the bladder" induced the greatest increase in abdominal EMG and IAP. "Tighten around the anus" induced greatest anal sphincter activity.

CONCLUSIONS

The pattern of urethral movement measured from transperineal US is influenced by the instructions used to teach activation of the pelvic floor muscles in men. Efficacy of PFM training may depend on the instructions used to train activation. Instructions that optimize activation of muscles with a potential to increase urethral pressure without increasing abdominal EMG/IAP are likely ideal. Neurourol. Urodynam. 35:457-463, 2016. © 2015 Wiley Periodicals, Inc.

Ultrasound assessment of urethral support in women with stress urinary incontinence during and after first pregnancy

OBJECTIVE

To investigate the association of bladder neck position, bladder neck mobility, and levator hiatal dimensions with symptoms of stress urinary incontinence (SUI) using transperineal ultrasonography in women during and after their first pregnancy.

METHODS

In this prospective observational study, 280 nulliparous pregnant women were evaluated at 12 weeks of gestation, 36 weeks of gestation, and 6 months postpartum. At each visit, symptoms of SUI were assessed and transperineal ultrasound examination was performed at rest, on pelvic floor contraction, and on Valsalva maneuver. Bladder neck position, bladder neck mobility, and levator hiatal dimensions were determined offline. Independent-samples t tests were used to compare ultrasound data between women with and without SUI. Because multiple t tests were performed, the statistical significance level was corrected using the Bonferroni method.

RESULTS

There were 18.8% women who reported symptoms of SUI at 12 weeks of gestation, 47.2% at 36 weeks of gestation, and 37.5% at 6 months postpartum. During pregnancy, women with SUI had a significantly larger hiatal area compared with women without SUI (P=.001-.003). After childbirth, women with SUI had a significantly more caudal and dorsal position of the bladder neck on Valsalva maneuver than women without SUI (P=.004 and P=.001, respectively). There were no significant differences in bladder neck mobility between women with and without SUI.

CONCLUSION

Stress urinary incontinence during first pregnancy is associated with a larger hiatal area. After childbirth, SUI is associated with a more caudal and dorsal position of the bladder neck on Valsalva maneuver.

Continence and micturition: an anatomical basis

Urinary incontinence remains an important clinical problem worldwide, having a significant socio-economic, psychological, and medical burden. Maintaining urinary continence and coordinating micturition are complex processes relying on interaction between somatic and visceral elements, moderated by learned behavior. Urinary viscera and pelvic floor must interact with higher centers to ensure a functionally competent system. This article aims to describe the relevant anatomy and neuronal pathways involved in the maintenance of urinary continence and micturition. Review of relevant literature focusing on pelvic floor and urinary sphincters anatomy, and neuroanatomy of urinary continence and micturition. Data obtained from both live and cadaveric human studies are included. The stretch during bladder filling is believed to cause release of urothelial chemical mediators, which in turn activates afferent nerves and myofibroblasts in the muscosal and submucosal layers respectively, thereby relaying sensation of bladder fullness. The internal urethral sphincter is continuous with detrusor muscle, but its arrangement is variable. The external urethral sphincter blends with fibers of levator ani muscle. Executive decisions about micturition in humans rely on a complex mechanism involving communication between several cerebral centers and primitive sacral spinal reflexes. The pudendal nerve is most commonly damaged in females at the level of sacrospinous ligament. We describe the pelvic anatomy and relevant neuroanatomy involved in maintaining urinary continence and during micturition, subsequently highlighting the anatomical basis of urinary incontinence. Comprehensive anatomical understanding is vital for appropriate medical and surgical management of affected patients, and helps guide development of future therapies.

Dynamics of male pelvic floor muscle contraction observed with transperineal ultrasound imaging differ between voluntary and evoked coughs

Coughing provokes stress urinary incontinence, and voluntary coughs are employed clinically to assess pelvic floor dysfunction. Understanding urethral dynamics during coughing in men is limited, and it is unclear whether voluntary coughs are an appropriate surrogate for spontaneous coughs. We aimed to investigate the dynamics of urethral motion in continent men during voluntary and evoked coughs. Thirteen men (28-42 years) with no history of urological disorders volunteered to participate. Transperineal ultrasound (US) images were recorded and synchronized with measures of intraabdominal pressure (IAP), airflow, and abdominal/chest wall electromyography during voluntary coughs and coughs evoked by inhalation of nebulized capsaicin. Temporal and spatial aspects of urethral movement induced by contraction of the striated urethral sphincter (SUS), levator ani (LA), and bulbocavernosus (BC) muscles and mechanical aspects of cough generation were investigated. Results showed coughing involved complex urethral dynamics. Urethral motion implied SUS and BC shortening and LA lengthening during preparatory and expulsion phases. Evoked coughs resulted in greater IAP, greater bladder base descent (LA lengthening), and greater midurethral displacement (SUS shortening). The preparatory inspiration cough phase was shorter during evoked coughs, as was the latency between onset of midurethral displacement and expulsion. Maximum midurethral displacement coincided with maximal bladder base descent during voluntary cough, but followed it during evoked cough. The data revealed complex interaction between muscles involved in continence in men. Spatial and temporal differences in urethral dynamics and cough mechanics between cough types suggest that voluntary coughing may not adequately assess capacity of the continence mechanism.