DYNAMIC MR-IMAGING COMPARED WITH EVACUATION PROCTOGRAPHY WHEN EVALUATING ANORECTAL CONFIGURATION AND PELVIC FLOOR MOVEMENT

OBJECTIVE. The aim of this study was to determine the agreement betwee n measurements of the anorectal configuration made with dynamic MR ima ging and with evacuation proctography. SUBJECTS AND METHODS. Ten women with constipation were examined sequentially using both standard evac uation proctography and dynamic MR imaging. Correlation and agreement between standard measurements of anorectal configuration at rest and d uring straining or evacuation of the rectum were evaluated. RESULTS. S ignificant correlation existed for anorectal junction descent (r = .7: p = .023), change in the anorectal angle (r = .78, p = .008), the pos ition of the rectal axis on straining (r = .62, p = .032), and rectoce le depth (r = .82, p = .004). The mean of the measurement differences for anorectal junction descent as measured using the two techniques wa s -0.23 cm (SD, 1.40 cm), The mean of the measurement differences for change of the anorectal angle was +15.3 degrees (SD, 27.92 degrees). C ONCLUSION. Standard measurements of anorectal configuration made using evacuation proctography and dynamic MR imaging show significant corre lation. However, in our study statistical agreement was poor for measu rement of anorectal junction descent and anorectal angle change, as se en on imaging obtained with the two techniques.