Urethral Strictures and Artificial Urinary Sphincter Placement

Is the Standard Artificial Urinary Sphincter AMS 800 Still a Treatment Option for the Irradiated Male Patient Presenting with a Devastated Bladder Outlet?

BACKGROUND

Circular urethral compression with an artificial sphincter allows control of voiding, even in patients with severe stress urinary incontinence, but it heightens the risk of urethral atrophy and erosion. This study of one of the largest populations of patients treated with radiotherapy investigates the additive effect of the post-radiogenic stricture of the membranous urethra/bladder neck on AMS 800 artificial urinary sphincter outcomes.

METHODS

In a retrospective multicenter cohort study, we analyzed patients fitted with an AMS 800, comparing those who had received radiotherapy with patients presenting a devastated bladder outlet (stricture of the membranous urethra/bladder neck). We determined the correlation between these groups of patients using both univariate and stepwise adjusted multivariate regression. The revision-free interval was estimated by a Kaplan-Meier plot and compared by applying the log-rank test. A p value below 0.05 was considered statistically significant.

RESULTS

Of the 123 irradiated patients we identified, 62 (50.4%) had undergone at least one prior desobstruction for bladder-neck/urethra stenosis. After a mean follow-up of 21 months, the latter tended to achieve social continence less frequently (25.7% vs. 35%; p = 0.08). Revision was required significantly more often for this group (43.1% vs. 26.3%; p = 0.05) due to urethral erosion in 18 of 25 cases. A stenosis recurred in five cases; desobstruction was performed in two cases, leading to erosion in both. Multivariate analysis revealed a significantly higher risk of revision when recurrent stenosis necessitated at least two prior desobstructions (HR 2.8; p = 0.003).

CONCLUSIONS

A devastated bladder outlet is associated with a lower proportion of men with social continence and a significantly higher need for revision compared with irradiated patients without a history of urethral stenosis. Alternative surgical procedures should be discussed beforehand, especially in cases of recurrent urethral stenosis.

Biomechanical study of the male lower urinary tract: Simulation of internal and external sphincters dyssynergia

Urethral sphincter dysfunction is an important cause of stress urinary incontinence (SUI). The most effective treatment is the insertion of an artificial urethral sphincter (AUS), which relies to a large extent on the surgeon's experience. However, there is no quantitative standard for cuff tightness, resulting in frequent postoperative complications. This study aimed to investigate the effect of internal and external sphincter dyssynergia on urodynamic parameters in the lower urinary tract. A geometric model of male lower urinary tract tissue was constructed from collodion slices, accounting for the active behavior of the internal and external sphincters. Normal and dyssynergic internal and external sphincters (active sphincter behavior was individually injured by 25%, 50%, 75%, or 100%) were simulated with fluid-structure interactions and changes in urethral stress, displacement, and urine flow rate were detected. We found that when the internal sphincter was injured by 25%, 50%, 75%, and 100%, urethral stress near the internal sphincter decreased by 8.3%, 15.6%, 24.3%, and 35.7%, respectively. Additionally, when the external sphincter was injured by 25%, 50%, 75%, and 100%, urethral stress near the external sphincter was reduced by 13.3%, 24.3%, 38.6%, and 46.6%, respectively. Internal sphincter injury primarily affects positions near the internal sphincter and prostate, while external sphincter injury affects the area between the prostate and urethral outlet. These data could facilitate the standardized evaluation of internal and external sphincter dysfunction and lead to novel methods of preoperative assessment for AUS surgery.

Transperineal bulbovesical anastomosis for extensive posterior urethral stenoses after treatment of prostatic disease

OBJECTIVES

We report our surgical experience of transperineal bulbovesical anastomosis (BVA) for extensive posterior urethral stenosis (PUS).

METHODS

Six male patients who had extensive PUS extending from the bulbomembranous urethra to the bladder neck due to prostatic disease treatment and underwent transperineal BVA between 2014 and 2020 were retrospectively reviewed. BVA was performed according to the elaborate perineal approach for pelvic fracture urethral repair with minor modifications. After confirming the absence of recurrent stenosis 6 months postoperatively, the patients were offered artificial urinary sphincter (AUS) placement for subsequent urinary incontinence (UI).

RESULTS

Median patient age was 68, and the etiology of PUS was radical prostatectomy for prostate cancer in four patients, brachytherapy for prostate cancer in one, and transurethral resection of the prostate for benign prostatic hyperplasia in one. All patients had been previously treated with multiple transurethral procedures such as urethrotomy and dilation. Median operative time and blood loss were 211 min and 154 ml, respectively. Five cases (83.3%) had no recurrent stenosis with a median follow-up of 45 months, but a single direct vision internal urethrotomy was performed in one (16.7%) due to restenosis. Four (66.7%) patients underwent AUS placement via transcorporal approach for subsequent UI, but two had it removed due to urethral erosion.

CONCLUSION

Transperineal BVA could effectively manage extensive PUS after prostatic disease treatment. Staged AUS placement could be a viable option for subsequent UI, but the risk of urethral erosion seemed high.

ATOMS (Adjustable Trans-Obturator Male System) in Patients with Post-Prostatectomy Incontinence and Previously Treated Urethral Stricture or Bladder Neck Contracture

(1) Background: Male stress incontinence in patients with previously treated urethral or bladder neck stricture is a therapeutic challenge. The efficacy and safety of the adjustable trans-obturator male system (ATOMS) in these patients is unknown. (2) Methods: All patients with primary ATOMS implants in our institution between 2014 and 2021 were included. The outcomes of patients with previously treated urethral or bladder neck stricture (≥6 months before ATOMS implant) and stable 16Ch urethral caliber were compared to those without a history of stricture. The primary endpoint was the dry patient rate, defined as the pad test ≤ 20 mL/day, and complication rate, including device removal. The secondary variable was self-perceived satisfaction using the Patient Global Impression of Improvement (PGI-I) scale. Wilcoxon rank sum test, Fisher’s exact test and logistic regression were performed. (3) Results: One hundred and forty-nine consecutive patients were included, twenty-one (14%) previously treated for urethral or bladder neck stricture (seven urethroplasty, nine internal urethrotomy and five bladder neck incision). After ATOMS adjustment, 38% of the patients with treated stricture were continent compared to 83% of those without (p < 0.0001). After weighted matched observations using propensity score pairing, the proportion of continent patients without a previous stricture was 56% (p = 0.236). Complications occurred in 29% of the patients with stricture and in 20% of those without (p = 0.34). The severity of the complications was distributed evenly among the groups (p = 0.42). Regarding self-perceived satisfaction with the implant, 90% of the patients with stricture perceived the results satisfactorily (PGI-I 1−3) compared to 97% of the rest (p = 0.167). Stricture was associated with radiotherapy (p < 0.0001) and time from prostatectomy to implantation (p = 0.012). There was a moderate correlation between previous stricture and the severity of incontinence, both evaluated according to the 24-h pad test (Rho = 0.378; p < 0.0001) and the ICIQ-SF questionnaire (Rho = 0.351; p < 0.0001). Multivariate analysis for the factors predictive of failure after ATOMS adjustment revealed previous stricture (OR 4.66; 95% CI 1.2−18.87), baseline 24-h pad test (per 100 mL, OR 1.28; 95% CI 1.09−1.52) and final cushion volume (per mL, OR 1.34; 95% CI 1.19−1.55). This model predicted dryness with an AUC of 92%. After the PSMATCH procedure using a propensity score, the model remained unchanged, with the previous stricture (OR 8.05; 95% CI 1.08−110.83), baseline 24-h pad test (per 100 mL, OR 1.53; 95% CI 1.15−2.26) and final cushion volume (per mL, OR 1.45; 95% CI 1.17−2) being independent predictors and an AUC of 93%. (4) Conclusions: ATOMS can be used to treat male stress incontinence in patients with a history of stricture, although the effectiveness of the device is reduced. On the other hand, the security and perceived satisfaction were equivalent for both groups.

Investigation of interaction phenomena between lower urinary tract and artificial urinary sphincter in consideration of urethral tissues degeneration

Lower urinary tract dysfunction pertains to symptoms related to the lower urinary tract (LUT), with consequent incontinence. Artificial urinary sphincters (AUS) are adopted to obtain continence conditions, mainly in male subjects, via urethral occlusion by applying pressure load, mostly operating on the basis of an empirical approach. Considering the frequent access of elderly patients to this surgical practice, tissue degradation related to aging phenomena must be investigated. Computational models of the LUT structures and the AUS systems have been designed to evaluate tissues mechanical stimulation and degenerative phenomena for reciprocal interaction. Virtual solid models of the LUT have been developed starting from biomedical images, as histological/morphometrical data. Segmentation procedures have been exploited to provide the three-dimensional reconstruction, and subsequent discretization techniques led to the finite element model. Contemporarily, a finite element model of a typical AUS device was developed. Numerical analyses have been performed to analyze interaction phenomena between AUS and LUT. Different conditions were investigated, modifying both loading conditions, as intraluminal pressure and AUS action, and urethral tissues properties. Particular attention was devoted to tissues parameters, aiming to evaluate the influence of tissues degeneration because of aging and/or pathologies.

Patency and Incontinence Rates After Robotic Bladder Neck Reconstruction for Vesicourethral Anastomotic Stenosis and Recalcitrant Bladder Neck Contractures: The Trauma and Urologic Reconstructive Network of Surgeons Experience

OBJECTIVE

To review a robotic approach to recalcitrant bladder neck obstruction and to assess success and incontinence rates.

MATERIALS AND METHODS

Patients with a recalcitrant bladder neck contracture or vesicourethral anastomotic stenosis who underwent robotic bladder neck reconstruction (RBNR) were identified. We reviewed patient demographics, medical history, etiology, previous endoscopic management, cystoscopic and symptomatic outcomes, urinary continence, and complications. Stricture success was anatomic and functional based upon atraumatic passage of a 17 Fr flexible cystoscope or uroflowmetry rate >15 ml/s. Incontinence was defined as the use of >1 pad per day or procedures for incontinence.

RESULTS

Between 2015 and 2017, 12 patients were identified who met study criteria and underwent RBNR. Etiology of obstruction was endoscopic prostate procedure in 7 and radical prostatectomy in 5. The mean operative time was 216 minutes (range 120-390 minutes), with a mean estimated blood loss of 85 cc (range 5-200 cc). Median length of stay was 1 day (range 1-5 days). Three of 12 patients had recurrence of obstruction for a 75% success rate. Additionally, 82% of patients without preoperative incontinence were continent with a median follow-up of 13.5 months (range 5-30 months). There was 1 Clavien IIIb complication of osteitis pubis and pubovesical fistula that required vesicopubic fistula repair with pubic bone debridement.

CONCLUSION

RBNR is a viable surgical option with high patency rates and favorable continence outcomes. This is in contrast to perineal reconstruction, which has high incontinence rates. If future incontinence procedures are needed, outcomes may be improved given lack of previous perineal dissection.

Reconstruction of Membranous Urethral Strictures

PURPOSE OF REVIEW

Due to the proximity of the rhabdosphincter and cavernous nerves to the membranous urethra, reconstruction of membranous urethral stricture implies a risk of urinary incontinence and erectile dysfunction. To avoid these complications, endoscopic management of membranous urethral strictures is traditionally favored, and bulboprostatic anastomosis is reserved as the main classical approach for open reconstruction of recalcitrant membranous urethral stricture. The preference for the anastomotic urethroplasty among reconstructive urologists is likely influenced by the familiarity and experience with trauma-related injuries. We review the literature focusing on the anatomy of membranous urethra and on the evolution of treatments for membranous urethral strictures.

RECENT FINDINGS

Non-traumatic strictures affecting bulbomembranous urethra are typically sequelae of instrumentation, transurethral resection of the prostate, prostate cancer treatment, and pelvic irradiation. Being a different entity from trauma-related injuries where urethra is not in continuity, a new understanding of membranous urethral anatomy is necessary for the development of novel reconstruction techniques. Although efficacious and durable to achieve urethral patency, classical bulboprostatic anastomosis carries a risk of de-novo incontinence and impotence. Newer and relatively less invasive reconstructive alternatives include bulbar vessel-sparing intra-sphincteric bulboprostatic anastomosis and buccal mucosa graft augmented membranous urethroplasty techniques. The accumulated experience with these techniques is relatively scarce, but several published series present promising results. These approaches are especially indicated in patients with previous transurethral resection of the prostate in which sparing of rhabdosphincter and the cavernous nerves is important in attempt to preserve continence and potency. Additionally, introduction of buccal mucosa onlay grafts could be especially beneficial in radiation-induced strictures to avoid transection of the sphincter in continent patients, and to preserve the blood supply to the urethra for incontinent patients who will require artificial urinary sphincter placement. The evidence regarding erectile functional outcomes is less solid and this item should be furtherly investigated.

What is the fate of artificial urinary sphincters among men undergoing repetitive bladder cancer treatment?

Purpose

Functional characteristics and durability of the artificial urinary sphincter (AUS) among patients who develop bladder cancer has been poorly characterized. We sought to evaluate AUS outcomes among patients subsequently diagnosed with bladder cancer, in order to describe device survivability when subject to diagnostic and therapeutic procedures such as cystoscopy, transurethral resection, and cystectomy.

Materials and Methods

We retrospectively reviewed 1,803 male patients treated with AUS surgery at a single institution between 1983-2014. We describe AUS device outcomes among patients undergoing surveillance and treatment for bladder cancer.

Results

Following AUS placement, 14 (0.8%) patients were subsequently diagnosed with and treated for bladder cancer and 4 patients with bladder cancer undergoing treatment and screening, subsequently received AUS placement. The median follow-up from device placement was 7.2 years (interquartile range [IQR], 2.8-11.5), and the median time from AUS placement to bladder cancer diagnosis was 6 (IQR, 0-9). There were a total of 8 primary and 1 secondary devices failures. Despite a median of 2 diagnostic cystoscopies (IQR, 1-6) and 0 bladder tumor resections (IQR, 0-0) per patient following device implantation, only 1 (5.6%) patient experienced an iatrogenic erosion related to urethral manipulation. Among those undergoing cystectomy (n=4), 1 device was left in situ without complication.

Conclusions

Bladder cancer surveillance and treatment with an AUS device in place appears to confer minimal additional risk to AUS survival. Careful attention should be given to device deactivation and use of the smallest caliber instruments available to minimize the risk of iatrogenic urethral erosion.

Urethral lumen occlusion by artificial sphincteric device: Evaluation of degraded tissues effects

Urinary incontinence can be surgically treated by means of artificial sphincters, based on a cuff that provides a pressure around the urethra to occlude the lumen. Considering the frequent access of elderly patients to this surgical practice, tissue degradation phenomena must be investigated, since they could affect treatment reliability and durability. The potential degradation can be interpreted considering a variation within soft tissue constitutive formulation, by means of a correlation between mechanical properties and tissues ageing. The overall compressibility varies, as characteristics aspect of soft tissue mechanical response with age, as well as the stiffness. The investigation is performed by means of a three dimensional numerical model of the urethral duct. The effects of the interaction phenomenon with a cuff is interpreted considering the changes, within the constitutive models, of the basic parameters that define the potential degradation process. The deformation related to compressibility is recalled, ranging between ten and fifty percent in dependence on the degradation level considered. This parameter, reported mostly as representative of the aging effect, shows a large variation that confirms the relevance of the investigation performed toward a sensitivity of the mechanical response of the urethral duct referred to the lumen occlusion.