Focal attenuation differences in pericystic liver tissue as seen on CT hepatic arteriography and CT arterial portography: observation using a unified helical CT and angiography system.

Abstract

To investigate nontumorous focal enhancement (FE) with computed tomographic hepatic arteriography (CTHA) and perfusion defect (PD) with computed tomographic arterial portography (CTAP) in pericystic liver tissue. Incidence, shape, and size of nontumorous FE on CTHA and PD on CTAP were examined in 100 consecutive noncirrhotic and 100 consecutive cirrhotic patients. FE was observed on CTHA in 77 noncirrhotic and 61 cirrhotic patients, whereas PD was observed on CTAP in 50 noncirrhotic and 51 cirrhotic patients. When both findings were visualized in both CT studies, the shape of the FE on CTHA was similar to the overlapping PD on CTAP in 81% of patients but was larger in 92% of patients. FE on CTHA and PD on CTAP are frequently noted in pericystic liver tissue. The size of FE on CTHA is often larger than PD on CTAP, although the shapes are generally the same. Size discrepancy suggests the presence of both portal supply and splanchnic venous drainage.