Magnetic Resonance Imaging Features Indicative of Permanent Colon Damage in Ulcerative Colitis: An Exploratory Study.

Background and aims: It is uncertain whether ulcerative colitis leads to accumulated bowel damage on cross-sectional image. We aimed to characterise bowel damage in patients with ulcerative colitis using magnetic resonance imaging [MRI], and to determine its relation with duration of disease and the impact on patients' quality of life.

Methods: In this prospective study, patients with ulcerative colitis [UC] in endoscopic remission underwent MRI without bowel cleansing, and completed quality-of-life questionnaires. Participants' magnetic resonance findings were analysed considering normal values and thresholds determined in controls with no history of inflammatory bowel disease [n=40], and in patients with Crohn's disease with no history of colonic involvement [n = 12]. Subjects with UC were stratified according to disease duration [< 7 years vs 7‒14 years vs > 14 years].

Results: We analysed 41 subjects with ulcerative colitis [20 women; Mayo endoscopic subscore 0 in 38 [92.7%] and 1 in three [7.3%]]. Paired segment-by-segment comparison of magnetic resonance findings in colonic segments documented as being affected by ulcerative colitis versus controls showed that patients with ulcerative colitis had decreased cross-sectional area [p ≤ 0.0034] and perimeter [p ≤ 0.0005] and increased wall thickness [p = 0.026] in all segments. Colon damage, defined as wall thickness ≥ 3 mm, was seen in 22 [53.7%] patients. Colon damage was not associated with disease duration or quality of life.

Conclusions: Morphological abnormalities in the colon were highly prevalent in patients with ulcerative colitis in the absence of inflammation. Structural bowel damage was not associated with disease duration or quality of life.