The cause of nontumorous defects of portal perfusion in the hepatic hilum revealed by CT during arterial portography.

Abstract

We investigated the cause of nontumorous defects of portal perfusion in the hepatic hilum revealed by CT during arterial portography (CTAP). One hundred sixty patients who simultaneously underwent CTAP and CT during hepatic arteriography of the common hepatic artery formed the basis of our study. The frequency, site, and shape of nontumorous defects of portal perfusion in the hepatic hilum on CTAP and the findings on CT during hepatic arteriography were determined. In 13 patients in whom nontumorous portal perfusion defects were observed on CTAP, CT was performed during selective angiography via the gastric artery, pancreaticoduodenal artery, or both. Nontumorous defects of portal perfusion were detected in 49 regions in 33 of the 160 patients (dorsum of segment IV, n = 30; dorsum of the lateral segment, n = 11; segment I, n = 8). Of the 33 patients, 16 had two defects each. Of the 49 nontumorous defects of portal perfusion, 38 showed enhancement on CT during hepatic arteriography. In the 13 patients who underwent CT during selective arteriography, enhancement due to nonportal venous inflow was seen in 16 of the 19 areas of decreased nontumorous portal perfusion (dorsum of segment IV, nine of 11; dorsum of the lateral segment, four of five; segment I, three of three). The main cause of nontumorous defects of portal perfusion in the hepatic hilum revealed by CTAP is decreased portal inflow due to nonportal supply via the parabiliary venous system. Thus, such lesions were also enhanced at a high frequency on CT during hepatic arteriography.