Endoscopic injection with polydimethylsiloxane for the treatment of pediatric urinary incontinence in the neurogenic bladder: Long-term results

Purpose: We report the long-term results of endoscopic injection of PDMS in correcting urinary incontinence in children with neurogenic bladder. Materials and Methods: We performed a single center, retrospective study of patients receiving endoscopic injections of PDMS. All procedures were performed as outpatient surgery using endoscopic guidance. Procedure tolerance was assessed at 15 days, and efficacy was evaluated at 3 months, 6 months and annually thereafter. Success was defined as periods of dryness between bladder voiding of more than 4 hours during the daytime without the need to wear pads.. Improvement was defined as periods of dryness greater than 2 and less than 4 hours with occasional protection. Results: A total of 49 children (21 boys and 28 girls) have received 1 or more injections of PDMS since 1995. Etiology was spina bifida in 41 patients (84%), with surgery (enterocystoplasty and/or bladder neck reconstruction) performed previously in 27 patients. Mean patient age was 14 years (standard deviation 4.8). Mean volume of PDMS per treatment was 3.6 ml. At the end of the 6-year mean followup 16 patients (33%) were continent and 7 (14%) were improved. Continence was unchanged in the remaining 26 patients (53%). After a significant deterioration of the results the outcome remained almost unchanged from 18 months of followup. Bladder neck surgery, bladder hyperactivity if medically controlled and gender have no influence statistically on the long-term results. Conclusions: Injection of PDMS for incontinence of neurogenic origin is a reliable technique that achieves long-term continence in almost a third of the patients. This procedure can be used either as first line treatment or in addition to other surgical techniques. The initial success of the procedure seems predictive of success in the long term, and results are stable after 18 months of followup.