Outcome and Complications of Retropubic and Transobturator Midurethral Slings Translated into Surgical Therapeutic Indices

Abstract

A number of studies have demonstrated that retropubic and obturator tape procedures are equally effective for cure of female stress urinary incontinence at 1 year after surgery. The use of the concept of risk/benefit in incontinence surgery is similar to pharmacology where the therapeutic index represents the ratio of desired effect to toxic effect. The surgical therapeutic index (STI) is the ratio between the cure and complication rate, with a high STI indicating greater safety. The aim of this retrospective cohort study was to determine and compare STIs of the retropubic tension-free vaginal tape (TVT) and 2 transobturator tape (TOT) procedures (Monarc and tension-free vaginal tape obturator [TVT-O]). Between 1998 and 2006, data was collected and analyzed for 237 patients with predominately female stress urinary incontinence, who underwent TVT (n = 257), Monarc (n = 95), or TVT-O (n = 85) procedures in a teaching hospital in the Netherlands. STIs were calculated for both groups by dividing cure by complication rate. The STI data for Monarc and TVT-O were presented as one combined group (TOT). Patients were followed for 2 and 12 months after surgery. At the 2-month follow-up, the STI in the TOT group was significantly higher than the TOT group (P < 0.05). After 12 months, however, no significant differences between the STIs in these groups were found. The similarity of STIs at 12 months was apparently due to longer lasting cure rates in the TVT group (P = 0.029) and an increased complication rate in the TOT group. These findings show that the benefit/risk of TVT and TOT based on the STI favors TOT in the short-time, but long-term results are similar among both groups. Both surgical procedures appear to have their own benefits and patients can choose between these two approaches.