Radiological-pathological correlation of mass lesions in the liver.

Thirty two human livers were removed at autopsy. These included 7 with space-occupying or tumour-like lesions, namely one with multiple cysts, three with haemangiomas, a lobated liver with multiple nodules of focal nodular hyperplasia, one with a metastasis which also had a small haemangioma and one with a hepatocellular carcinoma. Fine particle barium diluted 2:1 with water was injected by hand to fill the arterial system. In the lobated liver, the portal system was also filled. High definition radiographs of liver slices showed arteriographic detail not visible on angiography. The arteriographic appearances were correlated with the macroscopic and microscopic pathology. Liver cysts compress the arteries and arterioles but an apparent halo on the whole liver radiograph was shown to be spurious on a 1 cm thick high definition film. The small vessel pattern of haemangiomas is well demonstrated accounting for the hyperechoic sonograms but hypoechoic areas may also occur due to involution of or haemorrhage into tumours. The small lesions of focal nodular hyperplasia had a poor arterial supply but filled from a portal venous injection. Metastases had a peripheral network of small vessels, central necrosis and normal sized peripheral arteries with no large artery entering the tumour. In hepatocellular carcinoma, a large artery was demonstrated entering the tumour which was considerably more vascular than the metastases. These features should aid in distinguishing these lesions on sonography.