Unexpected Findings in Magnetic Resonance Enterography and Their Clinical Significance

Aims. To identify the prevalence of colonic and extraenteric incidental findings in magnetic resonance enterography (MRE) and their clinical significance. Methods. We retrospectively analysed 470 MRE studies carried out between March 2012 and 2014. Incidental findings were defined as those not expected from or made apparent on the referral. MRE reports were reviewed for colonic and extraenteric findings, subcategorised into "clinically significant" and "insignificant." Follow-up was identified from the electronic patient record. Results. The majority of MRE requests were made for inflammatory bowel disease (97%). In total, 114 incidental findings were noted in 94 (20%) scans performed. There were 29 "colonic" findings (25%) with 55% having a diagnosis of colitis. Out of 85 extraenteric findings, ovarian cysts (25%), renal cysts (10%), and abdominal lymphadenopathy (9%) were the commonest. Cumulatively, 59 cases were clinically significant (52%); of these, 30 findings were not previously diagnosed, amounting to 26% of all incidental findings. This led to intervention in seven patients. Conclusions. Incidental findings are common in MRE and there is a substantial proportion that is clinically significant and requires further investigation. There need to be stratification of risk and employment of local guidelines in order to achieve this.