Objective: We investigated whether CT signs can be used to predict hepatofugal flow in the main portal vein in patients with cirrhosis.
Materials and methods: We retrospectively identified 36 patients with cirrhosis, 18 with hepatopetal and 18 with hepatofugal flow in the main portal vein, who underwent contemporaneous abdominal sonography and CT. Two independent observers evaluated the following features on the randomized CT studies: diameter of the portal, splenic, and superior mesenteric veins; spleen size; and the presence of ascites, varices, or arterial phase portal venous enhancement. These data were correlated with the flow direction seen on sonography.
Results: A small main portal vein was the only sign significantly (p </= 0.05) predictive of hepatofugal flow by univariate and multivariate analyses. Observers 1 and 2 recorded a portal vein diameter of less than 1 cm in eight (44%) and seven (39%) of the 18 patients with hepatofugal flow compared with one (6%) and none of the 18 patients with hepatopetal flow, respectively (p < 0.02). Receiver operating characteristic analysis using the size of the portal vein to predict flow direction revealed an area under the curve of 0.83 for observer 1 and 0.74 for observer 2.
Conclusion: A diameter of less than 1 cm for the main portal vein is highly specific, although not sensitive, for hepatofugal portal venous flow in patients with cirrhosis. This sign may be useful when sonography is limited, or this sign may prompt sonographic assessment in patients not known to have hepatofugal flow.