Injection therapy for the treatment of stress urinary incontinence in women

The purpose of this review is to summarize the results of reports on injectable agents in the treatment of female stress urinary incontinence. Six agents were reviewed: Teflon; autologous fat; collagen; silicone microparticles; silicone microballoons, and pyrolytic carbon. Collagen was the most frequently reported agent and yielded a 1-year cure/improvement rate of 60-80%, but results worsened significantly with longer follow-up. Teflon has been used longer in the treatment of stress incontinence, but low long- and short-term success rates and reported complications such as particle migration have prevented its widespread acceptance. Autologous fat has been suggested as a natural injectable but its success rate has been disappointing. The injection of silicone microparticles is associated with a long-term success rate of about 70% in patients with intrinsic sphincter deficiency, and it can now be injected more easily without the need of urethroscopy. Silicone microballoons and pyrolytic carbon has recently been introduced into clinical practice with a short-term success rate of about 70%, but longer follow-up is needed. In conclusion, the long-term durability, cost-effectiveness, and some safety issues still have to be addressed by further clinical trials.