P258. Comparing MR enterocolonography to enteroscopy in Crohn's disease, especially focusing on small intestinal findings
K. Takenaka1, K. Ohtsuka1, Y. Kitazume2, M. Nagahori1, T. Fujii1, E. Saito1, M. Watanabe1, 1Tokyo Medical and Dental University, Gastroenterology and Hepatology, Tokyo, Japan, 2Tokyo Medical and Dental University, Radiology, Tokyo, Japan
To assess both active lesions and intestinal damage is important in Crohn's disease (CD). MR enterography is recommended as one of imaging techniques for detection of intestinal involvement of CD, but its findings in the deep small intestine have not been well compared to the endoscopic findings. We developed MR enterocolonography (MREC) to assess CD lesions in small intestine and colon simultaneously. On the other hand, device-assisted enteroscopy is able to assess the mucosa in detail, as well as to take histopathological specimen. Additionally, endoscopic therapeutic procedures such as balloon dilatation for stenoses are available. The aim of this study was to evaluate the efficacy of MREC by comparing its findings to those of enteroscopy.
MREC and enteroscopy were performed in the same day in eighty patients. The segmentation and assessment of the endoscopic findings were defined based on modified SES-CD. The terminal ileum was defined up to 10 cm from the ileocecal valve; the proximal ileum was defined as part of bowel extending between the proximal end of the terminal ileum up to 300 cm from the valve; the jejunum was defined as proximal part of small bowel. We summed the three scores of ‘size of ulcers’, ‘ulcerated surface’ and ‘affected surface’, and the active lesions were defined in the following manner; major mucosal lesions (MML: sum ≥5), all mucosal lesions (AML: sum ≥1). Major stenoses were defined as the lesions that the scope could not pass through. MREC sensitivity and specificity were studied.
The scope was passed in retrograde fashion and reached the proximal ileum in 78 patients (97.1%), the jejunum in 34 patients (42.5%), and the entire intestine in 9 patients (11.3%). In the assessment of active lesions, MREC sensitivities in the colon for MML and AML were 75.0% and 51.0%, while specificities were 91.3% and 94.3%, respectively. MREC sensitivities in the small intestine for MML and AML were 79.2% and 66.0%, while specificities were 89.2% and 95.7%, respectively. As for intestinal damage in the small intestine, MREC sensitivity and specificity for major stenoses were 57.1% and 91.0%, while those for all stenoses were 37.8% and 93.5%, respectively.
Our protocol of MREC technique is useful in detecting active lesions in both the small intestine and the colon. However, MR imaging is not sensitive enough in detecting stenosis. Evaluation of active lesions is important to determine medical treatment, while that of intestinal damage is important to determine the indication of surgical or endoscopic treatment. Adequate choice of modalities is required for assessing CD lesions.