Reliabilität der Introitussonografie nach Einlage eines spannungsfreien Vaginalbands nach dem TVT-Verfahren

Abstract

To date, the evaluation of TVT by ultrasound has not been standardized. The aim of this observational study was to evaluate the intraobserver and interobserver variability of introital ultrasound. Follow-up was performed for 202 patients after TVT procedure. The tape was characterized by the position in relation to urethral length (%) and the distance to the hypoechoic center of the urethra (mm). Furthermore, we assessed the shape of the tape (straight, curved or folded). All evaluations were performed by two experienced examiners (A, B) at rest and during Valsalva maneuver. All sonograms were archived digitally without measurement results. After 6 to 12 months, the sonograms were re-evaluated by one investigator (A). Depending on the first investigator, the results were compared as intraobserver (A-A) or interobserver (B-A) agreement. The first results were blinded for the second measurement. Agreement concerning the distances was assessed using the intraclass correlation coefficient (ICC). The concordance of the descriptive evaluation of the shape of the tape was characterized by the kappa coefficient (KC). The tape was regularly identified as an echogenic structure dorsal to the urethra. The intraobserver reliability concerning the position of the tape in relation to urethral length showed good reproducibility (at rest ICC 0.90, Valsalva maneuver: ICC 0.96). For the distance between the tape and the urethra at rest (ICC 0.83), there was also good reproducibility, but not during Valsalva maneuver (ICC 0.74). The shape of the tape showed only moderate reproducibility with accordance of 81% at rest (KC 0.68) and of 79% during Valsalva maneuver (KC 0.6). The interobserver comparisons showed good concordance in measuring the POS at rest (ICC 0.93), and during Valsalva maneuver (ICC 0.89), and the DIS at rest (ICC 0.89), and during Valsalva maneuver (ICC 0.87). The congruence of the estimation of the shape was 71% at rest (KC 0.44) and 72% during Valsalva maneuver (KC 0.49). The characterization of the TVT in the sagittal view by introital ultrasound shows good reproducibility with respect to position and distance, but not shape.