Lack of visualization of the portal venous tree in cirrhosis of the liver: a computed tomography finding with possible diagnostic significance.

During computed tomography (CT) scanning of the liver, the inferior vena cava can be identified as a separate structure of lesser density adjacent to the caudate lobe in two-thirds of patients without known hepatocellular disease. In patients with alcoholic (portal) cirrhosis of moderate to severe degree, intrahepatic portal veins may not be identified on CT scans, even though their inferior vena cavas can be definitely distinguished from the caudate lobe. Portal cirrhosis causes distortion and obliteration of the portal triads, which is presumably reflected by lack of visualization of intrahepatic portal veins during CT scanning.