The role of computed tomography in acute bowel ischemia.

Acute mesenteric ischemia representbi 0.1% to 0.01 % of al1 hospitalized patients. Its peak incidence is found bcîween the sixth and seventh decade and it is associated with a high mortality rate (estimated between 60 and 80% according to the litterature). The obsemed clinical presentations are not often clearly suggestive of mesenteric kchemia therefore its possibility must always bc kept in mind when confronted with an acute abdomen in a patient over the tige of sixty [q. We must at once make a distinction between two different c l i n d presentations [7] : acute mesenteric ischemiq whether it be from an occlusive (embolic or thrombotic) or non-occlusive (low flow state) angin, is characterized by a drarnatic clinical presentation (which is usually of sudden onset) and a dismal prognosis (60 to 90% mortality rate) which k, in large part, related to a much delayed diagnosis -... (which cxplains the extension and severity of intestinal lesions). acute venow ischemia from portomesenteric thrombosis, its frequency varying from 5 to 50% of cases according ta the series studied in the litterature, is actually better recoguized by the various imaging techniques, panicularly corn puted tomography . I ts clinical presentation is generally l m dramatic with a more gradua1 evolution and a less unfavorable outcome (spontaneously as weli as medicaily treated). Swere and extensive cases, homer, may require extensive resections of the small bowel. It is in these "venous" ischemia cases where computed tomography will pmvide the most useful elements for the definite diagnosis as ive11 sis for following the evolution of patients under medical treatment.