Magnetic resonance imaging of the small bowel in Crohn's disease

There may be advantages in using magnetic resonance imaging (MRI) in small-bowel disease. The aims of this study were to optimize the MRI examination technique and to evaluate the capabilities of MRI compared with those of conventional enteroclysis (CE).

MRI and CE were performed in 36 patients suspected of Crohn's disease. Based on 26 pilot studies optimal oral administration of plum juice and bulk fibre laxative was found. T2-weighted and gadolinium enhanced T1-weighted images were obtained using a breath-holding technique and butylscopolamine. Virtual endoscopy was performed. Conventional enteroclysis entailed duodenal intubation and administration of barium and air. Two radiologists evaluated the examinations independently. Finally, each patient scored the degree of discomfort, and preference for either MRI or CE was found.

The MRI technique ensured sufficient distension of the small bowel and small-bowel changes were found in 12 patients. In 3 patients this was not seen on conventional enteroclysis, which did not reveal any pathology that was not already seen on MRI. Pathological abdominal changes were found in 70% more patients during MRI than during conventional enteroclysis (p < 0.001). Endoscopic examination corresponded with the MRI findings. The examination quality decreased with increasing age (p = 0.002) and the interobserver agreement of the pathological changes was high (p < 0.001). Virtual endoscopy resulted in excellent demonstration of the mucosal surface. The examination discomfort scores obtained during the MRI were lower than those during conventional enteroclysis (p < 0.001).

MRI using the current technique is preferable to conventional enteroclysis because of superior demonstration of the entire small-bowel pathology, low level of patient discomfort and absence of radiation exposure.