By instilling fluid into the large intestine, it is possible to demonstrate the entire colon starting at the recto-sigmoidal boundary and ending at the cecum. Aside from demonstrating the intestinal lumen, a high resolving transducer will also allow detailed evaluation of the intestinal wall and its surrounding tissue. Examination of 61 patients with colonoscopic-verified diagnoses showed that polyps as well as colon cancer can be diagnosed by colonic sonography. Aside from such localized changes, colonic sonography can also demonstrate typical changes of Crohn's disease as well as the extent of colonic inflammatory involvement. Colonic sonography is a diagnostic procedure that permits specific statements regarding diseases involving the large intestine.