RADIOLOGY: SPLEEN: Case# 32871: SPLENORENAL SHUNT, PORTAL VEIN THROMBUS. This is a 66 year old female with delirium, UTI, and hepatic dysfunction. Abdominal ultrasound reveals portal vein thrombosis. The liver has a cirrhotic configuration. Within the right hepatic lobe, there is a 2 x 3 cm lesion that is slightly hypodense to hepatic parenchyma during the arterial phase of enhancement and is nearly isodense during the venous phase of enhancement. No other focal hepatic lesions were identified. Ascites is present. The spleen is enlarged. Multiple varices are seen at the gastroesophageal junction, the gastrohepatic ligament, and the splenic hilum. The portal vein is thrombosed. Thrombus extends approximately 6 cm into the superior mesenteric vein and partially occludes this vessel. The splenic vein is patent to very near the confluence. A large collateral extends from the splenic vein to the left renal vein. Portal vein thrombosis may be caused by hypercoagulable states, trauma, malignancy, cirrhosis, and infection. It may be accompanied by portal hypertension and its manifestations such as formation of collaterals, splenomegaly, and ascites. Portal vein thrombosis is readily diagnosed by CT and is best visualized with the incremental dynamic imaging technique. Acutely, the involved vessel enlarges, and the vessel wall may appear thickened and enhanced. There may be a small amount of contrast passing around the thrombus. The vessel itself has a relatively low central density. Serial examinations may show a change in the location or extent of thrombus, recanalization of the vessel, or retraction of the thrombus with collateral vein enlargement. Evidence of cavernous transformation of the portal vein may be seen.