Computerized tomography features of intestinal infarction: 56 surgically treated patients of which 5 with reversible mesenteric ischemia]

PURPOSE: Bowel infarction is a rare and typical condition of the elderly; despite improvements in diagnostic imaging and vascular surgery, bowel infarction remains a major cause of acute abdomen, with mortality rates ranging 70-80%. Diagnosis is often late because clinical signs, laboratory data and radiologic findings are aspecific. We investigated radiographic and particularly CT patterns of intestinal infarction in 56 patients submitted to surgery within 12 hours of admission. We also report the CT findings of 5 of these patients who had reversible mesenteric ischemia. MATERIAL AND METHODS: We retrospectively reviewed 56 cases of bowel infarction. The patients were 29 men and 27 women ranging in age 46-84 years (mean: 63). All the patients were submitted to plain radiography of the abdomen in different projections; emergency CT was carried out with i.v. contrast agent injection. We considered the following CT patterns: dilatation of intestinal loops > 2.5-3 mm, wall thickening > 3-4 mm, intraperitoneal effusion, stuffing of mesenteric vessels with diameter > 3 mm, air-fluid levels. RESULTS: Patients in the 7th decade of life were most frequently affected (38 cases), with an overall mortality rate of 59% (33 deaths). Plain radiography showed distention of bowel loops with air-fluid levels in 91% of cases. CT proved to be an accurate technique with higher sensitivity than radiography in detecting mesenteric edema and hemorrhage (68%), abdominal and pelvic effusion (88%), parietal pneumatosis (9%), wall thickening (29%), intraportal gas (7%), and thrombosis of superior mesenteric artery (3.5%). CT patterns in the 5 patients with reversible intestinal ischemia were wall thickening (80%), peritoneal effusion (80%), meteoric dilatatation (40%), a blurred appearance of mesenteric fat (40%). CONCLUSIONS: Angiography is a valuable imaging and treatment technique permitting the diagnosis of vascular occlusion and the intraarterial infusion of vasodilators, but it can be carried out in emergency in few centers only. This makes conventional radiology, and particularly CT, the only tool providing useful information for early diagnosis and treatment of bowel infarction. CT is more sensitive than radiography and does not exhibit the limitations of angiography--i.e., invasiveness, radiation exposure and complex organization. Therefore CT can presently be considered the method of choice in patients with suspected bowel infarction.