Hypothesis / aims of study
The artificial urinary sphincter is currently the gold standard for the treatment of neurogenic stress urinary incontinence due to intrinsic sphincter deficiency. An expert consensus propose a bladder neck cuff implantation. Actually, in this particular population, a bladder neck cuff is interesting owing to : the use of self intermittent catheterization, the pressure applied to bulbar urethra in wheelchair-bound patients, open bladder neck with urine-filled prostatic urethra and the increased risk of infection with a bulbar cuff and frequent endoscopic procedures.
Moreover, a recent multicenter study has suggested that a bladder neck insertion of the artificial urinary sphincter cuff in male patients with neurogenic stress urinary incontinence (SUI) may increase device survival as compared to the standard bulbar urethra cuff placement (1).
The robot-assisted approach has recently been described to try to minimize the technical complexity and surgical morbidity of bladder neck artificial urinary sphincter implantation (2). The aim of the present study was to report the peri-operative and short term functional outcomes of robot-assisted AUS implantation in male patients with neurogenic SUI due to intrinsic sphincter deficiency.
Study design, materials and methods
All male patients (> 18 years) who underwent a robot-assisted bladder neck artificial urinary sphincter implantation for neurogenic SUI at 3 university hospitals between 2010 and 2018 were included in a retrospective study. Over the study period, the robot-assisted approach was the only surgical approach used for bladder neck artificial urinary sphincter implantation and all devices were implanted at the bladder neck.
We report revision and explantation rates and short-term functional outcomes. Patients who did not use pads were defined as completely continent. They were defined as socially continent if they use 0 to 1 pad per day.
Twelve patients were included : 4 with spina bifida, 6 with spinal cord injury, two with a cauda equina syndrome. Mean age at the procedure was 37 years. Among them, 80% used self-intermittent catheterization as a voiding method.
Ten artificial urinary sphincters were implanted around the bladder neck with a robotic approach. Cuff size ranged from 8 to 10.
Two patients underwent a concomitant augmentation cystoplasty during the same operative time. We required one conversion to bulbar urethra implantation because of major abdominal adherences and one conversion to an open approach of the bladder neck cuff insertion owing a poor tolerance of pneumoperitoneum. These 2 patients were excluded of functional outcomes analysis.
The median lenght of stay was 4 days (3-8). The median post-operative catheterization duration was 6 days (1-28). The devices were activated in a mean time of 48 days (35-85) after implantation.
Mean follow-up was 200 days. Two explantations were needed in a mean-time of 31 days : one for an early device infection concerning a patient who underwent a concomitant augmentation cystoplasty and one for an erosion of the cuff.
One revision was performed one year after the implantation for a downsizing of the cuff.
At the last follow up, 8 patients still had their device in place (80%). Among them, 4 were completely continent (50%) and 3 had a social continence (38%). One patient did not recover his continence.
Interpretation of results
In this present study, we report the excellent functional outcomes of this technique : the global continence rate was 88% (50% of complete continence and 38% with a social continence).
However, our findings differ from the only preliminary series published to date (2) regarding the surgical morbidity and device outcomes.
This could be due to the smaller experience of our surgeons when compared to the aforementioned study. Actually, 4 of the 5 surgeons involved had a very little robotic experience (less than 50 robotic procedures). The concomitant augmentation cystoplasties can also explain these different outcomes. Indeed, one patient with a concomitant augmentation cystoplasty had an early infection of the device 2 days after the implantation, and needed an explantation of the artificial urinary sphincter. Previously, it had been shown that simultaneous augmentation cystoplasty lead to an initial increase in articial sphincter infection, but this difference seemed to disappear 3 years after the device insertion (3). Further studies are needed to assess the infection rate in a longer follow-up.