Hypothesis / aims of study
The artificial urinary sphincter (AUS) remains the gold standard treatment for men with bothersome, refractory stress urinary incontinence (SUI). There is little real life information about the contemporary indications, outcomes and complications after male artificial urinary sphincter (AUS) insertion. The aim of this study was to investigate the medium to long term outcomes following contemporaneous primary AUS implantation.
Study design, materials and methods
Retrospective analysis of a prospectively maintained database of men undergoing primary AUS implantation between 2008 and 2021 at a tertiary specialist centre was performed. Indications for surgery, mechanical and non-mechanical failure rates, patient satisfaction and the impact of radiotherapy on outcomes were specifically examined.
Results
In total 147 consecutive patients, median age 69 years and BMI 28, underwent primary AUS implantation over the study period. Although urodynamic evidence of stress urinary incontinence was present in 82% of patients, about 50% had concurrent detrusor overactivity and 10% underactivity. The primary indication for AUS insertion was post radical prostatectomy incontinence in 88% (129/147) of the cohort. The median time to AUS insertion in these patients was 3 years and 34% (50/147) of men received neoadjuvant or salvage radiotherapy prior to sphincter insertion. Median follow-up post AUS implantation was 6 years with a 27% (40/147) overall sphincter failure rate.
Of those who experienced AUS failure, 50% (20/40) patients underwent a revision of their sphincter, the majority (65%) to mechanical failure. Other reasons cited for revision included resiting of pump components (20%), repositioning of the urethral cuff tab (5%) and urethral atrophy (10%). The median time to first revision was 5.5 years. Only 2/147 patients required multiple revisions for mechanical failure.
20/147 patients required explantation of their sphincter, of whom three had, had a prior revision due to mechanical failure and 65% (13/20) had received radiotherapy. The majority (85%) of sphincter explantations were performed because of urethral erosions, with a median time to explantation of 2 years. Other causes for explantation were infection and unrecognised urethral injury at the time of insertion. Following explantation, eight patients had a second cuff placed via a transcorporal approach of which 75% (6/8) required explantation due to recurrent urethral erosion. The majority (83%) had received prior radiotherapy.
In total 68% (100/147) patients were satisfied following AUS insertion.
Interpretation of results
Urethral erosion was the primary cause of AUS explantation in our experience and previous radiotherapy was a significant risk factor regardless of the approach (perineal or transcorporal).