[MR Imaging Diagnostics in Proctology].

MR Imaging Diagnostics in Proctology Abstract. MR imaging is excellent for 1) the staging of rectal cancer 2) the assessment of chronic inflammatory bowel disease and 3) the performance of defecography. 1) MRI accuracy for the classification of the T- and N-stage is 75 - 95 % and 71 - 85 %, respectively. An infiltration of the mesorectal fat is easily detectable. 2) Due to the high soft-tissue contrast MRI depicts perirectal and perianal abscesses and fistulas, demonstrates the anatomical correlation to the anal sphincters and monitors the therapeutic response and the activity of the underlying disease. 3) MRI-movie-sequences allow for the demonstration of the dynamic processes during the defecography. With that technique it is possible to detect a paradox contraction of the puborectalis muscle in patients with anismus (dyskinesia) and to demonstrate a descensus of the pelvic floor, an incontinence, a rectocele or enterocele.