Upright 0.5T MR Proctography : an investigation into the repeatability and reproducibility of pelvic floor measures during seated defaecation

Motivation: Upright-MR Defaecating Proctography (uMRDP) enables studying physiological changes of pelvic floor (PF) organs during seated-defaecation and in our previous work showed promise in extracting conventional PF measures. In this study, we explore the optimum pulse sequence for dynamic imaging and whether Radiologists can use uMRDP to produce consistent PF metrices. Goal(s): To quantify the repeatability and reproducibility of PF metrices extracted from two expert Radiologists. Approach: Two Radiologists extracted multiple PF metrices from eight participants. We reported inter-observer agreement and intra-observer variability using relative absolute difference, correlation, and Bland-Altman plot. Results: Satisfactory agreement between the Radiologists show that uMRDP can provide consistent measurements. Impact: Upright MR defaecating proctography (uMRDP) facilitates capturing consistent pelvic floor (PF) metrices during seated defaecation. Thus, uMRDP can substitute supine MRDP. The non-ionising nature and complete PF coverage make it a feasible PF disorder assessment tool, complementary to fluoroscopic proctography