Acute thrombosis of the inferior vena cava and hepatic veins in patients with Budd-Chiari syndrome: CT demonstration

Abstract
We reviewed the CT findings in 17 patients with angiographically proved Budd-Chiari syndrome to determine the ability of CT to show acute thrombosis of the inferior vena cava (IVC) and hepatic veins. In eight patients with membranes (web or band) in the IVC, no thrombus was detected with CT or angiography. In the other nine patients, thrombi in the IVC and/or hepatic veins were seen as intraluminal filling defects that did not change in appearance on precontrast and postcontrast CT scans. Attenuation values of intraluminal filling defects of the IVC ranged from 38 to 42 H in four patients. High-attenuation intraluminal filling defects (60-70 H) of the IVC (five patients) and hepatic veins (one of five patients) were detected. Of these five patients, four had acute symptoms and one had chronic vague symptoms. The underlying disease was a web or band in the IVC and hepatic veins in three patients, invasive hepatocellular carcinoma in one, and injury to the IVC wall during hepatectomy in one. Inferior venacavography showed occlusion of the hepatic segment of the IVC in all five patients. Additional angiograms obtained by injection of contrast medium after a catheter tip was placed in the occluded hepatic IVC showed numerous filling defects suggestive of thrombi of recent onset, which correlated with the high-attenuation thrombi seen on CT scans in two patients. In the remaining three patients, high-attenuation areas in the IVC and hepatic veins also were considered to represent thrombi of recent onset because the attenuation values later decreased to 33-42 H. Spontaneous reduction in diameter of the thrombosed segment of the IVC was observed in four of the five patients. Knowledge of the CT features of acute thrombosis of the IVC and hepatic veins is useful in the early diagnosis of Budd-Chiari syndrome.