The use of polydimethylsiloxane in the treatment of incontinence after radical prostatectomy

Objective. To report the results of transurethral submucosal injection therapy of polydimethylsiloxane (PDS) to treat incontinence after radical prostatectomy (RP). Patients and methods. Since 1993, about 80 retropubic RPs have been carried out at our institution each year. Severe post-operative incontinence occurred in six patients, with a mean duration of incontinence after RP of 28 months. The pre-operative evaluation consisted of cysto-urethroscopy and urodynamics. Because we have no experience with artificial sphincter implantation, transurethral injection therapy was used to treat the post-operative incontinence, using PDS (vulcanized silicone rubber particles). This material has a mean particle size of 188 μm, providing stability of the material at the injection site. The six patients with severe post-operative incontinence were treated using injection therapy with PDS. Results. After a mean follow-up of 15.5 months, five patients, who suffered from day and night incontinence and required at least five pads per day, were dry after injection therapy. One patient improved significantly but still required two pads during the day, but was continent during the night; three patients required a second injection. A mean of 7.5 mL of PDS was used per patient and the side-effects of therapy (dysuria and urinary retention) were minimal. Conclusion. Because PDS has excellent biocompatibility, few side-effects or complications, transurethral injection therapy using silicone particles is a justifiable procedure for treating incontinence after RP.