EVALUATION OF THE COLORECTAL WALL IN NORMAL SUBJECTS AND PATIENTS WITH ULCERATIVE-COLITIS USING AN ULTRASONIC CATHETER PROBE

Background: Ulcerative colitis is usually evaluated by barium enema an d colonoscopy, methods of imaging that are limited to the mucosal surf ace. Endoscopic ultrasonography (EUS) is the best modality for the eva luation of transmural changes in the bowel wall. We therefore evaluate d the colorectal wall in normal control subjects and patients with ulc erative colitis using an ultrasonic catheter probe. Methods: Endoscopi c ultrasound with a catheter probe was performed on 36 normal control subjects (36 examinations) and 72 patients (111 examinations) with doc umented ulcerative colitis. Results: In normal control subjects, the t otal wall, mucosa, submucosa, and muscularis propria were significantl y thicker in the rectum than in the colon. There was no significant di fference in the thickness of the colon and rectum among different age groups or between men and women. In ulcerative colitis, we classified the boundary of each layer into three patterns (smooth, irregular, and blurred) and then classified the wall into six types. In Matts grade 2 and 3 ulcerative colitis lesions, the total wall and each layer were significantly thicker than lower grade lesions and normal control sub jects. For grade 1 and most of the grade 2 lesions, the boundary of ea ch layer was smooth. In some of the grade 3 lesions, the mucosa-submuc osa and submucosa-muscularis propria layer borders were abnormal. In a ll grade 4 cases, the mucosa-submucosa boundary was blurred. There was some correlation between the Matts grade and EUS findings except for Matts grade 3 lesions which had various EUS patterns. Conclusion: Endo scopic ultrasound with a catheter probe is a useful modality for the t ransmural assessment of the colorectal wall and, when used in conjunct ion with the many clinical and endoscopic parameters currently availab le, may contribute to the diagnosis and treatment of ulcerative coliti s.