Acute mesenteric ischemia

Arterial embolism or thrombosis, venous occlusion or low-flow states
Severe abdominal pain at presentation
MDCT crucial for diagnosis. Oral water with i.v. contrast and dual phase imaging. Sensitivity 93%. Specificity 96%

Acute transmural infarction: mural thinning, small intestine dilatation, reduced or absent mural enhancement
Non-occlusive mesenteric ischemia: mural thickening, mucosal hyper enhancement.
Mesenteric venous thrombosis: marked mural thickening, mucosal hyper enhancement, mesenteric stranding, vascular engorgement
Ascites in 2/3 of patients, mainly in venous thrombosis
Cardioembolic: signs of solid visceral infarcts. Segmental bowel involvement.
Pneumatosis intestinalis and portal venous gas – earlier considered to be specific for ischemia but no longer the case. Differentials: infection, inflammation, neoplasia, asthma, bowel dissension, raised intraluminal pressure