Mesenteric vein thrombosis: CT identification.

Superior mesenteric vein thrombosis was identified on computed tomographic scans in six patients. In each case, contrast-enhanced scans showed a high-density superior mesenteric vein wall surrounding a central filing defect. Four of the six patients had isolated superior mesenteric vein thrombosis. A fifth patient had associated portal vein and splenic vein thrombosis, and the sixth patient had associated portal vein and inferior vena cava thrombosis. The diagnosis of superior mesenteric vein thrombosis was confirmed by angiography in two patients and by surgery in a third. One of the six patients had acute ischemic bowel disease. The other five patients did not have acute ischemic bowel symptoms associated with their venous occlusion. This study defines the computed tomographic appearance of mesenteric vein thrombosis. A dense venous wall surrounding a central lucency representing blood clot was present in all six cases.