Dynamic magnetic resonance imaging: reliability of anatomical landmarks and reference lines used to assess pelvic organ prolapse

The aim of this study was to determine the intra- and interobserver reliability of dynamic magnetic resonance (MR) staging in pelvic organ prolapse patients. In 30 patients with pelvic organ prolapse, dynamic MR images were assessed independently by two observers. Various anatomical landmarks to asses pelvic organ prolapse were used in relation to the pubococcygeal line, H-line, and mid-pubic line. Clinical measurement points were assessed in relation to the mid-pubic line. The intraclass correlation coefficients (ICC) were calculated to describe the intra- and interobserver reliability. Overall, the intra- and interobserver reliability of MR imaging measurements was excellent to good. The pubococcygeal line showed superior reliability (ICC range 0.70-0.99). The reliability of clinical measurement points, however, were only moderate (ICC range 0.20-0.96). The intra- and interobserver reliability of quantitative prolapse staging on dynamic MR imaging were good to excellent. The pubococcygeal line appears the most reliable to use.