This article presents the differential diagnosis for small bowel ischemia. Clinical presentation of small bowel ischemia is variable, presenting with a myriad of specific or nonspecific clinical and laboratory findings. The imaging findings associated with small bowel ischemia are variable and combinations of findings may be necessary for definitive diagnosis. More specific imaging findings in patients with acute small intestine ischemia include bowel wall gas, mesenteric vessel occlusion, mesenteric venous gas, portal venous gas, or absence of bowel wall enhancement. Less specific imaging findings include small bowel wall thickening, mesenteric stranding, and mesenteric fluid. Further complicating the issue, several small intestinal disease processes may mimic ischemia both clinically and radiographically. These alternate diagnoses include infectious, inflammatory, and infiltrative processes. © 2008 Elsevier Inc. All rights reserved.