Hepatic perfusion: new perspectives at computed tomography

The dual blood supply to the liver, that of hepatic arterial supply and portal venous blood supply represents both opportunity and trouble for radiologists in using contrast material to detect liver neoplasms. It is this unique feature that allows one to optimize tumor detection by optimizing contrast flow to either the liver parenchyma or to tumors. Conversely, however, if one does not optimize contrast administration to take advantage of differences in blood flow between liver parenchyma and liver neoplasms, potentially tumors can be obscured at imaging. The focus of this article will be to review the physiology of liver blood flow and how various methods of contrast material administration can be used to optimize CT liver tumor detection and characterization.