The impact of prior external beam radiation therapy on device outcomes following artificial urinary sphincter revision surgery

Clinical and Urodynamic Determinants of Earlier Time to Failure for the Artificial Urinary Sphincter

OBJECTIVE

To determine clinical, surgical and urodynamic attributes associated with earlier AUS reintervention. The artificial urinary sphincter (AUS) is the gold standard treatment for postprostatectomy stress urinary incontinence. Factors impacting long-term device survival have not been investigated.

MATERIALS AND METHODS

We identified men with post-prostatectomy incontinence who underwent AUS reintervention from 2011 to 2021 at a single center. Urodynamic study, pad weights and voiding diaries are routinely assessed prior to AUS placement. Relationships between clinical, urodynamic and surgical variables and AUS reintervention were assessed using cox regression. Multiple imputation of chained equations was used to handle missing data elements, with truncated linear regression for continuous variables and logistic regression for binary variables.

RESULTS

A total of 524 records were reviewed and 92 met inclusion. Median time to AUS reintervention was 5.7 years (2.3, 9.4). Indications were mechanical failure (38; 41.3%), sub-cuff atrophy (37; 40.2%), erosion/infection (11; 11.9%) and other (6; 6.5%). On univariable testing, earlier intervention was associated with pad weight (P < .01), nocturnal voids (P = .01), bladder capacity (P = .01), bladder volume at strong sensation (P = .03), detrusor overactivity (P < .01) and maximum voiding pressure (P = .02). On multivariable analysis, earlier surgical intervention was associated with detrusor overactivity (HR 1.95, P < .01 CI 1.22-3.1) and pad weight (HR 1.0006, P = .02, CI 1.000-1.001).

CONCLUSIONS

Detrusor overactivity is associated with significantly shorter time to AUS failure. This information may allow for more individualized counseling.

Transcorporal vs. bulbar artificial urinary sphincter implantation in male patients with fragile urethra

PURPOSE

To compare transcorporal vs bulbar artificial urinary sphincter (AUS) implantation in men with fragile urethra and to investigate the risk factors of AUS explantation in this population.

METHODS

The charts of all male patients who had an AUS implantation between 2004 and 2020 in 16 centers were reviewed retrospectively. The primary endpoint was device explantation-free survival. Only patients with a fragile urethra were included in the present analysis. Fragile urethra was defined as a urethra carrying a high risk of cuff erosion because of prior radiotherapy and/or history of AUS explantation and/or history of urethral stricture surgery. The patients were divided in two groups according to the implantation site: bulbar vs transcorporal.

RESULTS

464 patients were included for analysis. 88 patients underwent a transcorporal AUS implantation and 376 underwent a bulbar AUS implantation. Explantation-free survival was similar in both groups (estimated 5-year explantation free survival rates 55.3% vs. 58.4%; p=0.98). In the subgroup of patients with a history of previous AUS explantation, transcorporal approach tended to bring longer explantation-free survival (2-year explantation-free survival: 61.9% vs. 58.2%; p=0.096). In multivariate analysis, the only risk factor of shorter explantation-free survival was the history of previous AUS explantation (HR=2.65; p=0.01).

CONCLUSIONS

Transcorporal AUS implantation was not associated with longer explantation-free survival. History of previous AUS explantation was the only risk factor associated with shorter explantation-free survival and this subgroup of patients may be the only one to draw benefits of transcorporal AUS implantation.

A comparison of artificial urinary sphincter outcomes after primary implantation and first revision surgery

Objective

The artificial urinary sphincter (AUS) is the gold standard for severe male stress urinary incontinence, though evaluations of specific predictors for device outcomes are sparse. We sought to compare outcomes between primary and revision AUS surgery for non-infectious failures.

Methods

We identified 2045 consecutive AUS surgeries at Mayo Clinic (Rochester, MN, USA) from 1983 to 2013. Of these, 1079 were primary AUS implantations and 281 were initial revision surgeries, which comprised our study group. Device survival rates, including overall and specific rates for device infection/erosion, urethral atrophy and mechanical failure, were compared between primary AUS placements versus revision surgeries. Patient follow-up was obtained through office examination, written correspondence, or telephone correspondence.

Results

During the study period, 1079 (79.3%) patients had a primary AUS placement and 281 (20.7%) patients underwent a first revision surgery for mechanical failure or urethral atrophy. Patients undergoing revision surgery were found to have adverse 1- and 5-year AUS device survival on Kaplan–Meier analysis, 90% vs. 85% and 74% vs. 61%, respectively (p<0.001). Specifically, revision surgery was associated with a significantly increased cumulative incidence of explantation for device infection/urethral erosion (4.2% vs. 7.5% at 1 year; p=0.02), with similar rates of repeat surgery for mechanical failure (p=0.43) and urethral atrophy (p=0.77).

Conclusions

Our findings suggest a significantly higher rate of overall device failure following revision AUS surgery, which is likely secondary to an increased rate of infection/urethral erosion events.