Ischemia and infarction of the small bowel and colon: spectrum of imaging findings

Excerpt

Mesenteric ischemia presents as an abdominal emergency due to decreased intestinal blood flow secondary to mesenteric arterial vascular hypoperfusion, occlusion, or impaired venous drainage [1]. The small bowel or colon may be involved. Distinction between intestinal ischemia and infarction sometimes is not considered adequately in the interpretative process: the ischemia may be a transient and a totally reversible event, whereas infarction may be one of the possible consequences that requires surgical or interventional management. Despite continuing advances in imaging and surgical techniques, early detection of intestinal ischemia before infarction develops remains difficult [2]. Early diagnosis is important to improve survival rates [2, 3]; in most cases of late or missed diagnosis, mortality rate from intestinal infarction is very high, from 60% to 90% [4‐6]. Prognosis of an ischemic intestinal insult depends upon clinical factors, such as its acuteness, duration and severity, the presence of collateral vascular circulation, the response of the mesenteric vascular branches and intestinal wall to the injury [7], extent of intestinal involvement, and the timeliness of diagnosis and intervention. From a phase in which the intestinal vascular injury may be suspected and the imaging findings of ischemia noted, the severity of mural damage may proceed rapidly to infarction with dire consequences. Differences in bowel wall findings may be appreciable between small bowel arterial and venous infarctions [8‐10]. …