PURPOSE: To find out clinical implications of sonographic findings in cases of ischemic colitis. MATERIALS AND METHODS: Sonographic images were retrospectively reviewed in 39 patients who were diagnosed of ischemic colitis either by endoscopic biopsy(n=36) or by surgery(n=3). Each patients, were described in one of the three segments(ascending colon, transverse colon, or descending including sigmoid colon) were involved. Morphologic patterns in cross section images were described in terms of which layer in the bowel wall was thickened and whether there was a distinction among layers. Degree of wall thickening and presence or absence of ascites were described in each patient and were correlated with longevity of hospitalization. Follow-up sonography was performed in six patients. RESULTS: Most commonly involved segment was descending including sigmoid colon(n=24), followed by the en-tire colon(n=6), ascending plus transvers colon(n=6), and in ascending colon only(n=3). The most common morphologic pattern was thickening of echogenic middle layer(n=25), followed by thickening of echolucent in-ner layer(n=12), panmural thickening with loss of distinction among layers(n=2). Nine patients with ascites were hospitalized for average period 13.3 days whereas 30 other patients without ascites were hospitalized for average 9.5 days. Nine patients with ascites showed more severe wall thickening(mean 15.3 mm) than patients without ascites(mean 10.3mm). When follow-up sonography was done, wall thickening was not seen in any of six patients, and their symptoms had been improved as well. CONCLUSION: In cases of ischemic colitis, severe wall thickenig and/or presence of ascites are associated with longer hospitalization(or necessity of surgery).