Does MR enterography offer added value after a recent CT in the evaluation of abdominal pain in Crohn's disease patients?

Purpose: To determine if there is added value in performing MR enterography shortly after a contrast-enhanced CT of the abdomen and pelvis in patients with Crohn's disease presenting with acute abdominal pain. Materials and methods: A total of 45 consecutive patients who underwent MRE examination < 7 days after a CT met our strict inclusion criteria. Independent and blinded review of both MRE and CT exams was performed by two abdominal radiologists. Results: There were no significant differences in detection of various findings associated with Crohn's disease between modalities. These findings included abscess, fistula, bowel wall thickening, free fluid, stricture, and bowel obstruction. There was moderate interobserver agreement with CT (Kappa: 0.52, 95% CI: [0.4-0.6]) and fair with MRE (Kappa: 0.36, 95% CI:[0.3 = 0.5]). Conclusion: The routine use of MRE after a diagnostic CT should be avoided, as it provides no additional valuable information, at the expense of extra patient risks, discomfort, and higher health care costs.