Porta hepatis: duplex Doppler US with angiographic correlation.

Duplex Doppler ultrasonography (US) and panhepatic angiography were performed and interpreted independently in 20 patients with suspected portal hypertension to assess the accuracy of duplex US in the porta hepatis. Hepatic arterial resistive indexes were correlated with corrected sinusoidal pressures. The results of duplex US agreed with those of angiography in 16 patients with a normal portal vein (including three with hepatofugal flow) and two with total thrombosis. One angiographically normal portal vein appeared thrombosed on an initial sonogram, but a second scan was normal. One case of partial thrombosis was not diagnosed with duplex US. Sensitivity and specificity for main portal vein disorders were 83% and 93%, respectively. Two patients had portal vein branch occlusions that were found by angiography but not by US. Portal vein echogenicity was neither sensitive nor specific for thrombosis. The resistive index of the hepatic artery was specific for portal hypertension when above .78, but it was not sensitive. Duplex US is accurate in prospectively assessing the direction of flow and the presence of total thrombosis in the portal vein, but partial thrombosis may not be detected on sonograms.