Dynamic CT features of arterioportal shunts in hepatocellular carcinoma.

Dynamic computed tomographic (CT) findings of 42 patients with hepatocellular carcinoma having angiographically proven arterioportal shunt were reviewed. CT findings related to arterioportal shunt were as follows: early enhancement of the portal vein, which showed a time-density curve similar to that of the aorta, markedly prolonged enhancement of the portal vein, dilated, abnormal intrahepatic vessels often accompanied by irregular, transiently enhanced areas, transient high attenuation of lobar or segmental distribution in the lobe contralateral to the main tumor, and transient wedge-shaped enhancement peripheral to the tumor. Dynamic CT usually detected arterioportal shunts involving larger portal veins as represented by any of the first four findings (14 of 17), whereas detection of arterioportal shunts involving smaller portal veins was lower in frequency (8 of 25), but such a shunt could be demonstrated as transient wedge-shaped enhancement peripheral to the tumor.