Modified Distal Urethral Polypropylene Sling (Canal Transobturator Tape) Procedure: Efficacy for Persistent Stress Urinary Incontinence After a Conventional Midurethral Sling Procedure

PURPOSE: Despite reports of persistent stress urinary incontinence (SUI) in patients after the midurethral sling (MUS) procedure, there is no widely accepted definition or cause of the condition. In many cases, the mesh implanted in the previous MUS procedure has been found to have migrated proximally. The aim of this study was to evaluate the efficacy of the modified distal urethral polypropylene sling, or canal transobturator tape (TOT), procedure for persistent SUI after a conventional MUS procedure on the assumption that persistent SUI after MUS is due to the location of the sling. METHODS: From January 2008 to April 2012, 31 female patients who underwent the canal TOT procedure presented with incontinence or lower urinary tract symptoms (LUTS) were included in this study. We identified patients who had been operated on by use of the conventional MUS procedure at other medical facilities, whose Valsalva leak pressure point was less than 120 cm-H(2)O by urodynamic study, and who were also diagnosed with persistent SUI. If vaginal or urethral mesh exposure was concomitant with persistent SUI, the mesh was removed completely or in part. Surgical procedures for canal TOT were identical to the original TOT procedures, except in the number and location of the vaginal incisions. Incontinence Impact Questionnaire-Short Form (IIQ-7) and Urogenital Distress Inventory-Short Form (UDI-6) scores were assessed preoperatively and at 3 months postoperatively. RESULTS: There were no intraoperative or postoperative complications. Twenty-eight patients (90.3%) showed improvement in incontinence or other LUTS. Postoperative scores of the IIQ-7 (0.65±0.48) and UDI-6 (3.48±2.28) were significantly improved compared with preoperative scores (1.26±0.58 and 7.52±4.30, respectively; P<0.05). CONCLUSIONS: Improper sling location is one of the major causes of persistent SUI after the conventional MUS procedure. Our results demonstrate that canal TOT may be an alternative method in the treatment of persistent SUI after the conventional MUS procedure.