Anastomosis between the hepatic artery and the extrahepatic collateral or between extrahepatic collaterals: observation on angiography.

Transcatheter arterial chemoembolisation for hepatocellular carcinoma is widely carried out not only through the hepatic artery but also through the extrahepatic collateral pathways. Anatomically, there are many anastomoses between the hepatic artery and the extrahepatic collateral as well as among the extrahepatic collaterals. However, these anastomoses may not be shown on angiography because the anastomosing branches are too small. These anastomoses may not only interfere with effective control of hepatocellular carcinoma by transcatheter arterial chemoembolisation but also cause unexpected procedure-related complications. Therefore, radiologists should have sufficient knowledge of these underlying anastomoses. In this report, we present our angiographic images.