The patient presented with abdominal pain and no characteristic certain differential and so, triphasic CT abdomen with entero-colonography preparation was done. The portal venous phase series (shown) shows occlusion of the superior mesenteric vein (SMV) with no signs of bowel ischemia.

Acute superior mesenteric vein thrombosis is one of the less common causes of acute mesenteric ischemia. Despite thrombosis of the SMV, small bowel necrosis is less likely to occur, presumably due to persistent arterial supply and some venous drainage via collaterals. Acute thrombosis may be difficult to detect in non-contrast studies or at the arterial phase as the thrombus may be iso- or hypodense and not usually hyperdense. The diagnosis is made on portal venous phase contrast-enhanced studies.