In order to investigate the lower urinary tract several imaging techniques may be used.
Transperineal ultrasound (TP-US) represents an attractive and alternative tool able to document vesico-urethral morphology at rest and during provocative manoeuvres, having a role also in the management and follow-up of female stress urinary incontinence (FSUI). The aim of the present study was to evaluate postoperative ultrasound parameters in female patients (pts) with FSIU and intrinsic sphincter deficiency (ISD), who underwent either a retropubic tension-free vaginal tape (TVT) or a transobturator suburethral sling (TVT-O).
Materials and Methods
Sixty-two pts with FSUI and ISD were treated with a tension-free suburethral sling: 18 cases using a TVT and 44 a TVT-O. A 3-month postoperative TP-US was performed in all cases with pt in gynaecologic position, under Valsalva manoeuvre and during maximal pelvic floor muscle contraction (Kegel). For each patient a Q-tip test was performed and the following parameters were evaluated: a angle (pubourethral angle), b angle (urethra-vesical angle), g angle (pubourethral angle) and the distance between the bladder neck and the tape.
In all cases postoperative TP-US showed the tape as a hypoechoic area beneath the urethra. Univariate analysis showed a statistically greater distance between the bladder neck and the tape in pts undergone TVT-O (mean 17 mm, range 12-28, p=0.01) than in those who underwent TVT (mean 21 mm, range 15-29); moreover during Kegel in the TVT-O group a angle was higher (mean 20°, range 11°-47°, p=0.02) and b angle lower (mean 135°, range 92°-165°, p=0.019) than the TVT group (mean 16°, range 5°-53° and mean 150°, range 116°- 198°, respectively). In multivariate analysis the distance between the bladder neck and the tape was the sole statistically significant parameter.
Our preliminary data might suggest a different pathophysiological mechanism underlying the two employed tension free procedures which could justify different success rates and complication rates in pts with FSUI and ISD undergone these surgical interventions.
TPUS represent a valid tool able to give important and useful information on tension-free suburethral slings used in the treatment of FSUI in order to better understand slings pathophysiological mechanisms, opening new paths to the improvement of FSUI research outcomes.