Distribution of iodized oil within the liver after hepatic arterial injection.

Radiography and microscopy were used to investigate the hepatic distribution of iodized oil injected into the hepatic artery in a rabbit VX2 tumor model. Iodized oil accumulates within hepatic metastases and in a ringlike fashion around them. Radiographic and histologic appearances were correlated, and it was concluded that ringlike deposition occurs in peritumoral sinusoids. There was no evidence that iodized oil is cleared by hepatic lymphatics. Early clearance of iodized oil into bile may possibly be caused by localized hepatic ischemia from oil microemboli or by direct phagocytosis by Kupffer cells. The remaining oil is washed through hepatic vasculature, circulates systemically, and is cleared by reticuloendothelial cells in lung, spleen, liver, and bone marrow. This mode of clearance, which has not been considered previously, may be important in the prediction of toxic effects caused by lipid and lipophilic antitumor agents administered via the hepatic artery.