Efficacy and safety of an alternative onabotulinumtoxinA injection paradigm for refractory overactive bladder.

AIMS: In studies utilizing a 20-injection-site paradigm of onabotulinumtoxinA treatment for overactive bladder (OAB), some patients performed clean intermittent catheterization (CIC). An alternative injection paradigm of fewer injections targeting the lower bladder may reduce the need for CIC by maintaining upper bladder function. This study evaluated the efficacy and safety of an unapproved alternative 10-injection-site paradigm targeting the lower bladder. METHODS: In this phase 4, double-blind, parallel-group study, patients with OAB and urinary incontinence (UI) for ≥6 months with ≥3 episodes of urinary urgency incontinence (no more than 1 UI-free day) and ≥8 micturitions per day over 3 days during screening were randomized 2:1 to onabotulinumtoxinA 100 U or placebo injected at 10 sites in the lower bladder. RESULTS: Of 120 patients, 78 in the onabotulinumtoxinA group and 39 in the placebo group had efficacy assessments. In the double-blind phase, mean change from baseline at week 12 in daily frequency of UI episodes was greater with onabotulinumtoxinA (-2.9) versus placebo (-0.3) (least squares mean difference [LSMD]: -2.99, p < 0.0001). Achievement of 100% (odds ratio [OR]: 6.15 [95% confidence interval, CI: 0.75-50.37]), ≥75% (OR: 7.25 [2.00-26.29]), and ≥50% improvement (OR: 4.79 [1.87-12.28]) from baseline in UI episodes was greater with onabotulinumtoxinA versus placebo. Reductions from baseline in the daily average number of micturitions (LSMD: -2.24, p < 0.0001), nocturia (LSMD: -0.71, p = 0.0004), and urgency (LSMD: -2.56, p < 0.0001) were greater with onabotulinumtoxinA than with placebo. Treatment benefit was improved or greatly improved in the onabotulinumtoxinA group (74.0% of patients) versus placebo (17.6%) (OR: 13.03 [95% CI: 3.23-52.57]). Mean change from baseline in Incontinence Quality of Life score was greater with onabotulinumtoxinA versus placebo (LSMD: 24.2, p = 0.0012). Two of 78 (2.6%) patients in the onabotulinumtoxinA group used CIC during the double-blind period; no females used CIC during the double-blind period. Commonly reported adverse events (≥5%) were urinary tract infection (UTI), dysuria, and productive cough for both groups; rate of UTI was higher with onabotulinumtoxinA versus placebo. CONCLUSION: In patients treated with onabotulinumtoxinA for OAB with UI, an unapproved alternative injection paradigm targeting the lower bladder demonstrated efficacy over placebo, with a low incidence of CIC.

Study design of a phase 4, real-world study (COMPOSUR) to evaluate vibegron in patients with overactive bladder.

BACKGROUND: Overactive bladder (OAB) is defined as urinary urgency accompanied by frequency and nocturia, with or without urge urinary incontinence (UUI). Vibegron, a selective ß3-adrenergic receptor agonist approved in the US in December 2020, demonstrated efficacy in reducing symptoms of OAB and was safe and well tolerated in the 12-week EMPOWUR trial and its 40-week, double-blind extension trial. The goal of the COMPOSUR study is to evaluate vibegron in a real-world setting to assess patient treatment satisfaction, tolerability, safety, duration of treatment, and persistence. METHODS: This is a 12-month, prospective, observational, real-world study, with an optional 12-month extension to 24 months, in the US assessing adults ≥ 18 years old starting a new course of vibegron. Patients must be previously diagnosed with OAB with or without UUI, symptomatic for ≥ 3 months before enrollment, and receive prior treatment with an anticholinergic, with mirabegron, or with a combination of an anticholinergic and mirabegron. Enrollment is performed by the investigator following exclusion and inclusion criteria guided by US product labeling, reinforcing a real-world approach. Patients complete the OAB Satisfaction with Treatment Questionnaire (OAB-SAT-q) monthly and the OAB Questionnaire short form (OAB-q-SF) and Work Productivity and Activity Impairment Questionnaire (WPAI:US) at baseline and monthly for 12 months. Patients are followed up via phone call, in-person visits, or telehealth (ie, virtual) visits. The primary endpoint is patient treatment satisfaction as determined by the OAB-SAT-q satisfaction domain score. Secondary endpoints include percent positive responses to individual OAB-SAT-q questions, additional OAB-SAT-q domain scores, and safety. Exploratory endpoints include adherence and persistence. DISCUSSION: OAB leads to a significant decrease in quality of life, as well as impairment of work activities and productivity. Persistence with OAB treatments can be challenging, often due to lack of efficacy and adverse effects. COMPOSUR is the first study to provide long-term, prospective, pragmatic treatment data for vibegron in the US and the resultant effect on quality of life among patients with OAB in a real-world clinical setting. Trial registration ClinicalTrials.gov identifier: NCT05067478; registered: October 5, 2021.

Neuro-Urology: Call for Universal, Resource-Independent Guidance.

Neurogenic lower urinary tract dysfunction (NLUTD), the abnormal function of the lower urinary tract in the context of neurological pathology, has been the subject of multiple efforts worldwide for the development of clinical practice guidelines. These guidelines are based on the same body of evidence, and are therefore subject to the same gaps. For example, sexual and bowel dysfunction in the context of NLUTD, optimal renal function assessment in those who are non-ambulatory or with low muscle mass, optimal upper tract surveillance timing, and modification of diagnostic and treatment modalities for low-resource nations and communities are inadequately addressed. In addition, many aspects of the conclusions and final recommendations of the guidelines are similar. This duplicative work represents a large expenditure of time and effort, which we believe could be focused instead on evidence gaps. Here, we call for a global unified approach to create a single, resource-independent, comprehensive guidance on NLUTD, neurogenic sexual, and neurogenic bowel dysfunction. Targeted research addressing the evidence gaps should be called for and pursued. This will allow for focus to shift to filling the gaps in the evidence for future guidelines.

An Evaluation of the Efficacy and Safety of Vibegron in the Treatment of Overactive Bladder.

Pharmacologic treatment for overactive bladder (OAB), which is characterized by bothersome symptoms such as urgency and urge urinary incontinence (UUI), includes anticholinergics and ß3-adrenergic receptor agonists. Anticholinergics are associated with adverse effects including dry mouth, constipation, cognitive impairment, and increased risk of dementia. Therefore, the drug class of ß3-adrenergic receptor agonists may represent an effective, safe treatment option. Vibegron, a ß3-adrenergic receptor agonist, was approved for use in Japan (2018) and the United States (2020). Over the past 3 years, 2 phase 3 trials (EMPOWUR, EMPOWUR extension) have been conducted with once-daily vibegron 75 mg for the treatment of OAB, and additional secondary and subgroup analyses have detailed the efficacy and safety of vibegron. In the international phase 3 EMPOWUR trial, treatment with vibegron was associated with significant improvements compared with placebo in efficacy outcomes of micturition frequency, UUI episodes, urgency episodes, and volume voided as early as week 2 that were sustained throughout the 12-week trial. The 40-week EMPOWUR extension study, following the 12-week treatment period, demonstrated sustained efficacy in patients receiving vibegron for 52 weeks. Treatment with vibegron was also associated with improvements in patient-reported measures of quality of life. Across studies, vibegron was generally safe and well tolerated. A separate, dedicated ambulatory blood pressure monitoring study showed that treatment with vibegron was not associated with clinically meaningful effects on blood pressure or heart rate. Across all studies, vibegron was efficacious, safe, and well tolerated and thus represents a valuable treatment option for patients with OAB. Here, nearly 1 year after US approval, we review the published data on efficacy and safety of vibegron 75 mg for the treatment of OAB.

Efficacy of Vibegron and Mirabegron for Overactive Bladder: A Systematic Literature Review and Indirect Treatment Comparison.

BACKGROUND: In the absence of head-to-head trials, we performed an indirect treatment comparison of the ß3-adrenergic agonists vibegron and mirabegron in the treatment of overactive bladder (OAB). METHODS: PubMed, Embase, and Cochrane Library were searched for articles related to phase 3, double-blind, controlled trials of vibegron 75 mg and mirabegron 25/50 mg in patients with OAB. Efficacy outcomes included change from baseline at weeks 4, 12, and 52 in mean daily number of total urinary incontinence episodes and micturitions and mean volume voided/micturition. Effect size was computed as placebo-subtracted change from baseline (weeks 4, 12) or active control (tolterodine)-subtracted change from baseline (week 52) for each treatment group. Adverse events (AEs) are presented descriptively. RESULTS: After removal of duplicates, 49 records were identified, and after screening 9 met inclusion criteria for analysis. Vibegron showed significantly greater reduction in mean daily number of total incontinence episodes than mirabegron 25 mg at week 4, mirabegron 50 mg (weeks 4, 52), and tolterodine (weeks 4, 12) (P < 0.05, each) and significantly greater improvement in volume voided versus mirabegron 25 mg (week 12), mirabegron 50 mg (weeks 12, 52), and tolterodine (week 4) (P < 0.05, each). Confidence intervals of point estimates overlapped zero for all other comparisons of vibegron and mirabegron (25 or 50 mg) or tolterodine, indicating no significant differences between treatments for these time/endpoints. Urinary tract infection, hypertension, and dry mouth were the most commonly occurring AEs for vibegron, mirabegron, and tolterodine, respectively, in the short-term trials; hypertension was the most commonly occurring AE with all three treatments in the long-term trials. CONCLUSIONS: Vibegron was associated with significant improvement in total incontinence episodes versus mirabegron at 4 and 52 weeks and volume voided at 12 and 52 weeks. Improvement in micturitions was similar between vibegron and mirabegron or tolterodine. Incidence of AEs was generally comparable between vibegron and mirabegron.

The AUA/SUFU Guideline on Adult Neurogenic Lower Urinary Tract Dysfunction: Treatment and Follow-up.

PURPOSE: The clinician treating patients with neurogenic lower urinary tract dysfunction (NLUTD) needs to balance a variety of factors when making treatment decisions. In addition to the patient's urologic symptoms and urodynamic findings, other issues that may influence management options of the lower urinary tract include cognition, hand function, type of neurologic disease, mobility, bowel function/management, and social and caregiver support. This Guideline allows the clinician to understand the options available to treat patients, understand the findings that can be seen in NLUTD, and appreciate which options are best for each individual patient. This allows for decisions to be made with the patient, in a shared decision-making manner, such that the patient's quality of life can be optimized with respect to their bladder management. MATERIALS AND METHODS: A comprehensive search for studies assessing patients undergoing evaluation, surveillance, management, or follow-up for NLUTD was conducted from January 2001 through October 2017 and was rerun in February 2021 to capture newer literature. The primary search returned 20,496 unique citations. Following a title and abstract screen, full texts were obtained for 3,036 studies. During full-text review, studies were primarily excluded for not meeting the PICO criteria. One hundred eight-four primary literature studies met the inclusion criteria and were included in the evidence base. RESULTS: This guideline was developed to inform clinicians on the proper evaluation, diagnosis, and risk stratification of adult patients with NLUTD and the non-surgical and surgical treatment options available. Additional statements on urinary tract infection and autonomic dysreflexia were developed to guide the clinician. CONCLUSIONS: NLUTD patients may undergo non-surgical and surgical treatment options depending on their level of risk, symptoms, and urodynamic findings. Appropriate follow-up, primarily based on their risk stratification, must be maintained after treatment.

The AUA/SUFU Guideline on Adult Neurogenic Lower Urinary Tract Dysfunction: Diagnosis and Evaluation.

PURPOSE: The clinician treating patients with neurogenic lower urinary tract dysfunction (NLUTD) needs to balance a variety of factors when making treatment decisions. In addition to the patient's urologic symptoms and urodynamic findings, other issues that may influence management options of the lower urinary tract include cognition, hand function, type of neurologic disease, mobility, bowel function/management, and social and caregiver support. This Guideline allows the clinician to understand the options available to treat patients, understand the findings that can be seen in NLUTD, and appreciate which options are best for each individual patient. This allows for decisions to be made with the patient, in a shared decision-making manner, such that the patient's quality of life can be optimized with respect to their bladder management. MATERIALS AND METHODS: A comprehensive search for studies assessing patients undergoing evaluation, surveillance, management, or follow-up for NLUTD was conducted from January 2001 through October 2017 and was rerun in February 2021 to capture newer literature. The primary search returned 20,496 unique citations. Following a title and abstract screen, full texts were obtained for 3,036 studies. During full-text review, studies were primarily excluded for not meeting the PICO criteria. One hundred eight-four primary literature studies met the inclusion criteria and were included in the evidence base. RESULTS: This guideline was developed to inform clinicians on the proper evaluation, diagnosis, and risk stratification of patients with NLUTD and the non-surgical and surgical treatment options available. Additional statements on urinary tract infection and autonomic dysreflexia were developed to guide the clinician. This Guideline is for adult patients with NLUTD and pediatric NLUTD will not be discussed. CONCLUSIONS: NLUTD patients should be risk-stratified as either low-, moderate-, high-, or unknown-risk. After diagnosis and stratification, patients should be monitored according to their level of risk at regular intervals. Patients who experience new or worsening signs and symptoms should be reevaluated and risk stratification should be repeated.

Pulse article: survey of neurogenic bladder management in spinal cord injury patients around the world.

STUDY DESIGN: Online survey distributed to healthcare professionals (HCPs) involved in care of spinal cord injury (SCI) patients with neurogenic lower urinary tract dysfunction (NLUTD). OBJECTIVES: Identify and bring awareness to the variation of neurogenic bladder management in around the world. SETTING: International online questionnaire. METHODS: A 32-question survey was drafted and circulated among a global network of SCI experts for review. The survey was disseminated to healthcare professionals involved in the care of NLUTD in SCI patients via social media, grassroots methods, and international societies. The survey was available for 6 weeks and respondents answered questions regarding SCI population demographics, access to care, common neurogenic bladder management, diagnostic and imaging methods, complications, and follow up. RESULTS: A total of 296 healthcare professionals, 132 from North America, 87 from Europe, 27 from Asia, 24 from Australia, 14 from South America, and 6 from Africa, responded to the survey. Global concurrence was noted among management method for patients without adequate hand function, first-line treatment for neurogenic detrusor overactivity, and common complications. Continents highly differed in responses regarding management method for patients with adequate hand function, frequency of patients reusing catheters, timing of urodynamics, and duration of antibiotic therapy for urinary tract infections. CONCLUSIONS: The results of this international survey demonstrate the variability and uniqueness in neurogenic bladder management in SCI patients around the world. Increased international discourse and education will improve global communication and transparency with the efforts of reducing discrepancies in care.

Biologic Grafts for Use in Pelvic Organ Prolapse Surgery: a Contemporary Review.

PURPOSE OF REVIEW: Pelvic organ prolapse (POP) is a common condition and there is a plethora of surgical techniques available to address this problem. We present a review of biologic grafts, including the latest literature to help guide a surgeon's choice on the type of biologic materials to augment repairs. RECENT FINDINGS: Since the 2019 Food and Drug Administration (FDA) ban on mesh, including xenograft, there is a sparsity of biologic graft products available for POP repairs. This has led to a significant decrease in surgical application. Surgeons must be familiar with the biochemical properties, processing, and clinical application of biologic grafts prior to use. They should also be familiar with alternative operative techniques that utilize autografts, although there is limited outcome data on these techniques. With heightened awareness of mesh and its complications, biologic grafts have made a resurgence. Surgeons must be well versed on their available options. Current literature is limited, and studies have not demonstrated superiority of biologic graft over native tissue repairs for prolapse. Nevertheless, there is a role for these types of biologic graft material in specific patient populations. Future studies are warranted.

A Primary Care Provider's Guide to Management of Neurogenic Lower Urinary Tract Dysfunction and Urinary Tract Infection After Spinal Cord Injury.

Neurogenic lower urinary tract dysfunction (NLUTD), previously termed neurogenic bladder dysfunction, is a common secondary complication of spinal cord injury (SCI). It is associated with significant morbidity, reduced quality of life, increased health care costs, and mortality. Primary care providers (PCPs) play an important role in optimizing urohealth over the life span. This article will review NLUTD in SCI, its complication, surveillance, and management. PCPs should be aware of SCI-related NLUTD, its complications, management, and surveillance recommendations, and when to refer to a specialist.

Contemporary multicenter outcomes of continent cutaneous ileocecocystoplasty in the adult population over a 10-year period: A Neurogenic Bladder Research Group study.

AIMS: Evidence is sparse on the long-term outcomes of continent cutaneous ileocecocystoplasty (CCIC). We hypothesized that obesity, laparoscopic/robotic approach, and concomitant surgeries would affect morbidity after CCIC and aimed to evaluate the outcomes of CCIC in adults in a multicenter contemporary study. METHODS: We retrospectively reviewed the charts of adult patients from sites in the Neurogenic Bladder Research Group undergoing CCIC (2007-2017) who had at least 6 months of follow-up. We evaluated patient demographics, surgical details, 90-day complications, and follow-up surgeries. the Mann-Whitney U test was used to compare continuous variables and χ² and Fisher's Exact tests were used to compare categorical variables. RESULTS: We included 114 patients with a median age of 41 years. The median postoperative length of stay was 8 days. At 3 months postoperatively, major complications occurred in 18 (15.8%), and 24 patients (21.1%) were readmitted. During a median follow-up of 40 months, 48 patients (42.1%) underwent 80 additional related surgeries. Twenty-three patients (20.2%) underwent at least one channel revision, most often due to obstruction (15, 13.2%) or incontinence (4, 3.5%). Of the channel revisions, 10 (8.8%) were major and 14 (12.3%) were minor. Eleven patients (9.6%) abandoned the catheterizable channel during the follow-up period. Obesity and laparoscopic/robotic surgical approach did not affect outcomes, though concomitant surgery was associated with a higher rate of follow-up surgeries. CONCLUSIONS: In this contemporary multicenter series evaluating CCIC, we found that the short-term major complication rate was low, but many patients require follow-up surgeries, mostly related to the catheterizable channel.

Recommendations for evaluation of neurogenic bladder and bowel dysfunction after spinal cord injury and/or disease.

Objective: To provide an overview of clinical assessments and diagnostic tools, self-report measures (SRMs) and data sets used in neurogenic bladder and bowel (NBB) dysfunction and recommendations for their use with persons with spinal cord injury /disease (SCI/D).Methods: Experts in SCI/D conducted literature reviews, compiled a list of NBB related assessments and measures, reviewed their psychometric properties, discussed their use in SCI/D and issued recommendations for the National Institutes of Health (NIH), National Institute of Neurological Disorders and Stroke (NINDS) Common Data Elements (CDEs) guidelines.Results: Clinical assessments included 15 objective tests and diagnostic tools for neurogenic bladder and 12 for neurogenic bowel. Following a two-phase evaluation, eight SRMs were selected for final review with the Qualiveen and Short-Form (SF) Qualiveen and the Neurogenic Bowel Dysfunction Score (NBDS) being recommended as supplemental, highly-recommended due to their strong psychometrics and extensive use in SCI/D. Two datasets and other SRM measures were recommended as supplemental.Conclusion: There is no one single measure that can be used to assess NBB dysfunction across all clinical research studies. Clinical and diagnostic tools are here recommended based on specific medical needs of the person with SCI/D. Following the CDE for SCI studies guidelines, we recommend both the SF-Qualiveen for bladder and the NBDS for bowel as relatively short measures with strong psychometrics. Other measures are also recommended. A combination of assessment tools (objective and subjective) to be used jointly across the spectrum of care seems critical to best capture changes related to NBB and develop better treatments.

New Technologies and Applications in Sacral Neuromodulation: An Update.

Recently rechargeable devices have been introduced for sacral neuromodulation (SNM) with conditional safety for full-body magnetic resonance imaging (MRI). Currently a recharge-free SNM device represents the standard implant; however, it is only approved for MRI head scans. As further new technologies with broader MRI capabilities are emerging, the advantages as well as disadvantages of both rechargeable versus recharge-free devices will be briefly discussed in this commentary from the perspective of patients, healthcare professionals, and providers.

Persistent Vaginal Leakage in the Setting of an Apical Vaginal Sinus Tract: A Case Report.

Fistulas are defined as abnormal connections between 2 organ, vessels, or structures. They can often present in the genitourinary tract as a result of iatrogenic injury during pelvic surgery. A 46-year-old female presents many years after a hysterectomy for persistent vaginal leakage with concern for a vesicovaginal fistula. Computed tomography urogram, intravenous retrograde pyelogram, and cystoscopy were negative for vesicovaginal fistula; however, a vaginal sinus tract was noted and further explored. This case report will describe the use of both laparoscopy and concomitant vaginoscopy to diagnose and, ultimately, surgically excise a salpingovaginal fistula.

Translating promising strategies for bowel and bladder management in spinal cord injury.

Loss of control over voiding following spinal cord injury (SCI) impacts autonomy, participation and dignity, and can cause life-threatening complications. The importance of SCI bowel and bladder dysfunction warrants significantly more attention from researchers in the field. To address this gap, key SCI clinicians, researchers, government and private funding organizations met to share knowledge and examine emerging approaches. This report reviews recommendations from this effort to identify and prioritize near-term treatment, investigational and translational approaches to addressing the pressing needs of people with SCI.

Optical Clearing of Vaginal Tissues in Cadavers.

A nonsurgical laser procedure is being developed for treatment of female stress urinary incontinence (SUI). Previous studies in porcine vaginal tissues, ex vivo, as well as computer simulations, showed the feasibility of using near-infrared laser energy delivered through a transvaginal contact cooling probe to thermally remodel endopelvic fascia, while preserving the vaginal wall from thermal damage. This study explores optical properties of vaginal tissue in cadavers as an intermediate step towards future pre-clinical and clinical studies. Optical clearing of tissue using glycerol resulted in a 15-17% increase in optical transmission after 11 min at room temperature (and a calculated 32.5% increase at body temperature). Subsurface thermal lesions were created using power of 4.6 - 6.4 W, 5.2-mm spot, and 30 s irradiation time, resulting in partial preservation of vaginal wall to 0.8 - 1.1 mm depth.

Best practice policy statement on urodynamic antibiotic prophylaxis in the non-index patient.

AIMS: Antibiotic prophylaxis before urodynamic testing (UDS) is widely utilized to prevent urinary tract infection (UTI) with only limited guidance. The Society of Urodynamics, Female Pelvic Medicine, and Urogenital Reconstruction (SUFU) convened a Best Practice Policy Panel to formulate recommendations on the urodynamic antibiotic prophylaxis in the non-index patient. METHODS: Recommendations are based on a literature review and the Panel's expert opinion, with all recommendations graded using the Oxford grading system. RESULTS: All patients should be screened for symptoms of UTI and undergo dipstick urinalysis. If the clinician suspects a UTI, the UDS should be postponed until it has been treated. The first choice for prophylaxis is a single oral dose of trimethoprim-sulfamethoxazole before UDS, with alternative antibiotics chosen in case of allergy or intolerance. Individuals who do NOT require routine antibiotic prophylaxis include those without known relevant genitourinary anomalies, diabetics, those with prior genitourinary surgery, a history of recurrent UTI, post-menopausal women, recently hospitalized patients, patients with cardiac valvular disease, nutritional deficiencies or obesity. Identified risk factors that increase the potential for UTI following UDS and for which the panel recommends peri-procedure antibiotics include: known relevant neurogenic lower urinary tract dysfunction, elevated PVR, asymptomatic bacteriuria, immunosuppression, age over 70, and patients with any indwelling catheter, external urinary collection device, or performing intermittent catheterization. Patients with orthopedic implants have a separate risk stratification. CONCLUSIONS: These recommendations can assist urodynamic providers in the appropriate use of antibiotics for UDS testing. Clinical judgment of the provider must always be considered.

Optical clearing of vaginal tissues, ex vivo, for minimally invasive laser treatment of female stress urinary incontinence.

Near-infrared laser energy in conjunction with applied tissue cooling is being investigated for thermal remodeling of the endopelvic fascia during minimally invasive treatment of female stress urinary incontinence. Previous computer simulations of light transport, heat transfer, and tissue thermal damage have shown that a transvaginal approach is more feasible than a transurethral approach. However, results were suboptimal, and some undesirable thermal insult to the vaginal wall was still predicted. This study uses experiments and computer simulations to explore whether application of an optical clearing agent (OCA) can further improve optical penetration depth and completely preserve the vaginal wall during subsurface treatment of the endopelvic fascia. Several different mixtures of OCA's were tested, and 100% glycerol was found to be the optimal agent. Optical transmission studies, optical coherence tomography, reflection spectroscopy, and computer simulations [including Monte Carlo (MC) light transport, heat transfer, and Arrhenius integral model of thermal damage] using glycerol were performed. The OCA produced a 61% increase in optical transmission through porcine vaginal wall at 37°C after 30 min. The MC model showed improved energy deposition in endopelvic fascia using glycerol. Without OCA, 62%, 37%, and 1% of energy was deposited in vaginal wall, endopelvic fascia, and urethral wall, respectively, compared with 50%, 49%, and 1% using OCA. Use of OCA also resulted in 0.5-mm increase in treatment depth, allowing potential thermal tissue remodeling at a depth of 3 mm with complete preservation of the vaginal wall.

Computer simulations of thermal tissue remodeling during transvaginal and transurethral laser treatment of female stress urinary incontinence.

BACKGROUND AND OBJECTIVES: A non-surgical method is being developed for treating female stress urinary incontinence by laser thermal remodeling of subsurface tissues with applied surface tissue cooling. Computer simulations of light transport, heat transfer, and thermal damage in tissue were performed, comparing transvaginal and transurethral approaches. STUDY DESIGN/MATERIALS AND METHODS: Monte Carlo (MC) simulations provided spatial distributions of absorbed photons in the tissue layers (vaginal wall, endopelvic fascia, and urethral wall). Optical properties (n,µa ,µs ,g) were assigned to each tissue at λ = 1064 nm. A 5-mm-diameter laser beam and incident power of 5 W for 15 seconds was used, based on previous experiments. MC output was converted into absorbed energy, serving as input for finite element heat transfer simulations of tissue temperatures over time. Convective heat transfer was simulated with contact probe cooling temperature set at 0°C. Variables used for thermal simulations (κ,c,ρ) were assigned to each tissue layer. MATLAB code was used for Arrhenius integral thermal damage calculations. A temperature matrix was constructed from ANSYS output, and finite sum was incorporated to approximate Arrhenius integral calculations. Tissue damage properties (Ea ,A) were used to compute Arrhenius sums. RESULTS: For the transvaginal approach, 37% of energy was absorbed in the endopelvic fascia target layer with 0.8% deposited beyond it. Peak temperature was 71°C, the treatment zone was 0.8-mm-diameter, and 2.4 mm of the 2.7-mm-thick vaginal wall was preserved. For transurethral approach, 18% energy was absorbed in endopelvic fascia with 0.3% deposited beyond the layer. Peak temperature was 80°C, treatment zone was 2.0-mm-diameter, and 0.6 mm of 2.4-mm-thick urethral wall was preserved. CONCLUSIONS: Computer simulations suggest that transvaginal approach is more feasible than transurethral approach. Lasers Surg. Med. 49:198-205, 2017. © 2016 Wiley Periodicals, Inc.