A new simple technique for 3D ultrasound assessment of the pelvic floor muscles

Aly Youssef*, Elisa Montaguti*, Luisa Cariello*, Tullio Ghi*, Olimpia Sanlorenzo*, Gianluigi Pilu*, Nicola Rizzo*
* Department of Obstetrics and Gynecology, Sant’Orsola-Malpighi Hospital, University of Bologna, Italy

Objectives: To assess the reproducibility of a new technique: the 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. In addition, we aimed to study the intermethod agreement between the new technique and the 3D rendering method.
Methods: We acquired a static 3DUS transperineal volume from 124 nulliparous asymptomatic and 118 women with symptoms of pelvic floor dysfunction. 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 both in asymptomatic and symptomatic women. In addition, a high agreement was demonstrated between the new technique and 3D rendering in both groups. No systematic difference was noted in any of the reliability studies performed. Moreover, the time needed for hiatal area measurement by Omniview-VCI was significantly shorter than the 3D rendering method (45±7 vs 72±13 seconds, P value <0.001).
Conclusions: Omniview-VCI is a reliable method for pelvic hiatal area measurement in women with and without symptoms of pelvic floor dysfunction.

Figure: The Omniview-Volume Contrast Imaging (VCI) technique. The line of the Omniview-VCI is drawn along the plane of least pelvic hiatal dimensions, between the posterior margin of the symphysis pubis and the anterior margin of the puborectalis muscle where it defines the anorectal angle, including a thickness of 10 to 20 mm. The plane of hiatal dimensions is automatically displayed on the right hand side (B). The trace method is then used to measure the pelvic hiatal area.


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