Reliability of Omniview-VCI for pelvic hiatal area measurement under contraction and Valsalva’s maneuver in women with and without symptoms of pelvic floor dysfunction

Elisa Montaguti*, Giuseppina Pacella*, Ginevra Salsi *, Olimpia Sanlorenzo*, Gianluigi Pilu*, Nicola Rizzo*, Aly Youssef*
* Department of Obstetrics and Gynecology, Sant’Orsola-Malpighi Hospital, University of Bologna, Italy

Objectives: To assess the reproducibility of the technique “Omniview-Volume contrast imaging (Omniview-VCI, GE Healthcare)” for the measurement of pelvic hiatal area in women with and without symptoms of pelvic floor dysfunction under contraction and during Valsalva’s maneuver. In addition, we aimed to study the intermethod agreement with 3D rendering method.
Methods: We enrolled 34 women with symptoms of pelvic floor dysfunction and 34 women without any symptoms as control. For each women we acquired a static 3D ultrasound transperineal volume and two dynamic volumes under contraction and during Valsalva’s maneuver. Each 3D dataset was analyzed by means of the Omniview-VCI technique to measure the pelvic hiatal area, twice by an operator and once by another in order to assess intra- and interobserver reproducibility. We then measured hiatal area using 3D rendering method to evaluate inter-method agreement. Reproducibility and inter-method agreement were studied by means of intraclass correlation coefficient (ICC) and Bland-Altman method.
Results: Hiatal area measurements by Omniview-VCI technique showed high intraobserver and interobserver reproducibility not only as regarding static measurement, as previously demonstrated, but also in dynamic acquisitions. In addition, a high agreement was demonstrated between the new technique and 3D rendering in both contraction and Valsalva’s maneuver.
Conclusions: Omniview-VCI is a reliable method for pelvic hiatal area measurement even during contraction and Valsalva’s maneuver.


Figure: Omniview-Volume Contrast Imaging (VCI) technique visualizing pelvic hiatal area at rest, during contraction and during Valsalva’s maneuver in a nulliparous asymptomatic woman.


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