Dynamic study of iodized oil in the liver and blood supply to hepatic tumors. An experimental investigation in several animal species.

A better understanding of the biologic behavior of embolic agents in the liver and the blood supply to hepatic tumors is of utmost importance in embolization and chemoembolization. In vivo microscopy, which allows observation of live hepatic circulation, was used in this study along with angiography, vascular cast technique, and light and electron microscopy. Iodized oil injected into the hepatic artery passed through the peribiliary plexus to enter the portal vein, and subsequently traversed the hepatic sinusoids. The time required for clearance of the oil from the liver and recovery of the microcirculation depended largely on the patency of the hepatic artery. Kupffer cells actively captured and phagocytosed iodized oil droplets in hepatic sinusoids. The hepatic tumors were confirmed to have a dual blood supply from the hepatic artery and the portal vein. Embolization of either the hepatic artery or the portal vein alone did not completely stop the blood circulation in the tumors. A reciprocal relationship between the hepatic artery and the portal vein in the blood supply to hepatic tumors was demonstrated dynamically and intrahepatic arterioloportal communications, especially the peribiliary plexus, play an important role in the tumor circulation. The current trans-catheter intraarterial management of hepatic tumors is insufficient in that it deals only with the hepatic arterial blood supply and ignores that from the portal vein. Iodized oil creates the potential for dual embolization of the hepatic tumor through a single hepatic arterial catheterization.