Objective: : To evaluate the effect of voiding mechanism on cure rate of stress urinary incontinence in patients undergoing midurethral sling procedures.
Methods: : Retrospective study of 121 patients who underwent midurethral sling procedures (retropubic or transobturator [TO]) between January 2006 and October 2007. Voiding mechanism was determined by preoperative pressure flow studies. Subjects were dichotomized to either "detrusor voiders" (N = 61) or "Valsalva voiders" (N = 60). Primary outcome was cure of stress urinary incontinence.
Results: : At a mean follow-up of 6.74 months, the overall success rate was 87.6% (85.7% for retropubic and 89.4% for TO). "Valsalva voiders" had a higher risk of failure compared with "detrusor voiders" (20% vs. 4.9%, respectively; OR = 4.83, 95% CI: 1.29, 18.12, P = 0.012). This effect was significant for TO slings (P = 0.025); however, sling type was not an independent predictor of failure.
Conclusions: : Valsalva voiding mechanism is associated with an increased risk of failure of synthetic midurethral slings.