Fifty patients affected with Crohn's disease were examined with CT in a 12-month period; 39 of them underwent an intestinal enema and 24 a colon enema. Our goal was to assess the comparative contribution of CT and conventional radiology to the diagnosis of this disease. CT proved to be the method of choice to diagnose wall diseases with colon or small bowel wall thickening, which is usually homogeneous as demonstrated in 94% of the patients, intraabdominal abscesses in 3 patients (6%), perianal (4%), enterocutaneous (2%) and enteromuscle (2%) fistulas. CT was comparable to barium studies for rectovaginal (2%) and enterocolic (4%) fistulas. Conventional radiology was better than CT to assess mucosal diseases and ileum-ileal fistulas which were demonstrated with small bowel enema in 4 patients and in one patient only with CT. Therefore, we believe CT to be a complementary method to barium studies and a necessary tool for the correct staging of this disease, especially relative to the diagnosis of extramural lesions.