Voiding function after tension-free vaginal tape: a longitudinal study.

BACKGROUND The tension-free vaginal tape (TVT) has become popular for the surgical treatment of urodynamic stress incontinence. It seems to function via an intermittent obstructive effect that is easily demonstrated on imaging, although there is no agreement regarding its effect on voiding. AIMS The present study was designed to longitudinally evaluate flowmetry indices and voiding symptoms after TVT placement. METHODS A total of 145 consecutive patients were seen at yearly intervals after TVT placement, and 108 have now attended at least twice. A standardised questionnaire was filled in and a clinical stress test performed. The patients were asked to void for flowmetry; ultrasound was performed translabially for residual urine, tape position and mobility. RESULTS After TVT placement, maximum flow rate (MFR) centiles dropped from 49.66 (SD 32.45) to 22.86 (SD 23.56), P < 0.001. However, when first and last postoperative visits were compared, there was a significant increase in MFR centiles (20.07 (SD 20.83) to 24.92 (SD 23.94), P = 0.021). This effect appeared to be almost linear over time when analysed on anova. The residuals decreased highly significantly (P < 0.001). This was accompanied by a reduction in symptoms of voiding dysfunction such as 'poor stream' (P = 0.024), 'straining to void' (P = 0.038) and 'incomplete emptying' (P = 0.019). CONCLUSIONS The tension-free vaginal tape reduces MFR and flow rate centiles. It can have an obstructive effect on voiding, although this does not appear to be a major clinical problem. Voiding seems to improve over time, and this is accompanied by a reduction in the prevalence of symptoms of voiding dysfunction.