Fig. 3

Changes in the intrahepatic arterial flow with and without balloon occlusion. Without balloon occlusion, the feeding artery flows into the tumor and drains out to the hepatic parenchyma, forming corona enhancement. In Group A, the feeding artery is reconstructed by the peribiliary plexus and communicating arcade distal to the balloon occlusion. The arterial inflow was kept in the tumor, and the intra-arterial pressure around the tumor was preserved. Corona enhancement was thus observed. In Group B, the collateral arteries such as the peribiliary plexus and communication arcade do not develop enough to maintain the intratumoral arterial pressure. Corona enhancement is not present in this group. In Group C, collateral arteries including the isolated artery, peribiliary artery and communicating arcade feed the tumor entirely or partially. These flows do not contain contrast material, and thus CTHA shows decreased perfusion or perfusion defect. CA catheter, FA feeding artery, N the area of contrast distribution in noncancerous liver parenchyma, T tumor, C coronal enhancement, BA balloon (inflated), PP peribiliary plexus, CoA communicating arcade, IA isolated artery