Intersegmental attenuation difference on CT caused by partial Budd-Chiari syndrome secondary to hepatocellular carcinoma: report of two cases.

For two patients with partial Budd-Chiari syndrome secondary to hepatocellular carcinoma, dynamic CT was evaluated. The obstructed hepatic veins were both the middle and left hepatic veins in Case 1 and the right hepatic vein in Case 2. The area affected by obstructed hepatic vein(s) was seen as low density on both unenhanced and contrast enhanced CT in Case 1 and as high density on enhanced CT in Case 2. The border of attenuation differences caused by the obstruction of the middle (Case 1) or right (Case 2) hepatic vein was intersegmental planes of the anterior segment of the right lobe, and that caused by the obstruction of the left hepatic vein was the intersegmental plane of the medial third of the left lateral segment. Once intersegmental attenuation difference is recognized on CT, partial Budd-Chiari syndrome should be considered.