Injectable polydimethylsiloxane for treating incontinence in children with the exstrophy-epispadias complex: long-term results

OBJECTIVE To present our experience with the use of injectable polydimethylsiloxane (Macroplastique (TM), Uroplasty, Minneapolis, MI, USA) for treating incontinence in children with the exstrophy-epispadias complex (EEC), as incontinence continues to be a challenging problem in such children, and although the primary management of EEC has developed over the last few decades, with early closure and reconstruction of the penis, achieving satisfactory continence status remains elusive. PATIENTS AND METHODS We retrospectively reviewed the hospital records of 52 patients (41 boys and 11 girls, mean age at first injection 6.6 years, range 3.6-16.7) with EEC who had injections with Macroplastique between January 1991 and February 2004; 34 had bladder exstrophy and 18 primary epispadias. For this study we defined success as complete dryness with no use of pads or nappies. Improvement was defined as being occasionally wet but with dry intervals lasting >= 4 h. RESULTS The mean (range) follow-up was 4.6 (0.5-9) years. Twenty patients had one injection, 10 had two, 13 had three, six had four, two had six and one had seven injections. In most patients a maximum of three injections predicted the outcome. The injection of Macroplastique was successful in nine patients (17%; with an annual follow-up, two at 1-2 years, three at 2-5 years and four at > 5 years), whilst 17 (33%) improved significantly (one at < 1 year, two at 1-2 years, eight at 2-5 years and six at > 5 years). Those patients comprised five of 18 (27%) with epispadias and four of 34 (12%) with exstrophy. A history of previous surgery and gender had no significant effect on the outcome. Overall half the patients benefited from the procedure. CONCLUSIONS This series confirms that injection with Macroplastique is minimally invasive, durable in significantly many patients and has a reasonable success rate. A history of previous surgery and gender had no significant effect on the outcome. Patients with epispadias are more likely to benefit from an injection with Macroplastique than those with bladder exstrophy. A maximum of three injections is predictive with reasonable certainty of any benefit from the procedure.