Intraurethral sphincter prosthesis to treat hyporeflexic bladders in women: does it work?

To assess the efficacy and safety of a new intraurethral sphincter prosthesis to treat hyporeflexic bladders in women.

Between July 1997 and December 1998, 18 women (mean age 45.8 years, range 26-84) with neurogenic voiding disorders and a hyporeflexic bladder were examined prospectively. All but one patient (who used the Crédé manoeuvre) emptied their bladder using clean intermittent catheterization. The women were fitted with a prosthesis consisting of a valve and a pump inside a short self-retaining silicone device, which was activated by a magnetic remote control unit. The evaluation before implantation comprised a medical history, a neurological evaluation, urodynamic recordings and urine cultures. The follow-up after implantation included a monthly clinical assessment, a symptom questionnaire, urine culture, ultrasonographic examinations and replacement of the device if necessary. Urine samples were also cultured if there was any discomfort or fever.

At 16 months of follow-up, only six of 18 patients continued to use the implant (mean follow-up 9.6 months) and were satisfied. In 10 patients major incontinence around the catheter, or irritation, led to removal of the device. Two patients were unable to learn how to transfer to the toilet to empty their bladder; therefore, their implant was removed and they were treated with a suprapubic catheter. Two patients died from unrelated causes. Twelve patients had positive bacteriuria while fitted with the device; six of them became symptomatic. Usually, only symptomatic lower urinary tract infections were treated. Technical problems occurred often; 14 catheters showed technical dysfunction and had to be replaced early and three external remote control units broke for no reason. Despite normal short-term cystoscopic findings (three patients), long-term urethral damage cannot be excluded. Indeed, the six patients who remain fitted with the device already show some widening of their urethra.

This experience with the new device was disappointing; in eight of the 18 patients incontinence appeared or worsened and led to removal of the device. Technical problems were common. The other concern is that significant long-term urethral damage could be expected, as observed with indwelling catheters over time. Thus, although this device may function for a short period, it is unsuitable for long-term use.