A new simple technique for 3-dimensional sonographic assessment of the pelvic floor muscles

The purpose of this study was to assess the reproducibility of a new technique for 3-dimensional (3D) pelvic floor sonography: OmniView combined with Volume Contrast Imaging (VCI; GE Healthcare, Kretz Ultrasound, Zipf, Austria) for pelvic hiatal area measurement. In addition, we aimed to study the intermethod agreement between the new technique and the standard 3D rendering method.

We acquired a static 3D sonographic transperineal volume from 124 nulliparous asymptomatic women and 118 women with symptoms of pelvic floor dysfunction. Each 3D data set was analyzed by the OmniView-VCI technique to measure the pelvic hiatal area twice by one operator and once by another to assess intraobserver and interobserver reproducibility. The first operator later measured the hiatal area using the 3D rendering method to evaluate intermethod agreement. Reproducibility and intermethod agreement were studied by the intraclass correlation coefficient and Bland-Altman method.

Hiatal area measurements by the OmniView-VCI technique showed high intraobserver and interobserver reproducibility in both asymptomatic and symptomatic women. In addition, high agreement was shown between the new technique and 3D rendering in both groups. No systematic differences were noted in any of the reliability studies performed. The new technique took slightly less time to calculate the hiatal area than the standard rendering method in both asymptomatic and symptomatic women.

OmniView-VCI is a reliable method for pelvic hiatal area measurement. Further studies are needed to assess its reliability under contraction and the Valsalva maneuver and to evaluate its usefulness and reproducibility for diagnosis of levator ani lesions.