Functional Hepatography

Abstract

The study of the outflow tracts of the liver has remained, for the most part, in the realm of anatomical investigations. Plastic casts obtained by injection-corrosion technics have provided information on the configuration and structural changes of the hepatic vein system in health and disease (5, 13). Postmortem perfusion experiments have added some insight into the complex nature of the phenomena that, in life, may regulate the flow of blood through the liver (8, 14). In the living subject, hepatic vein manometries have been used in an effort to obtain data concerning the physiological and physiopathological behavior of hepatic outflow tracts (10–12, 22). From the radiologic point of view, two primary approaches to the visualization of the hepatic vein system have been explored, both consisting in the intraluminal injection of contrast medium into an hepatic vein branch. By the first approach, where a catheter is advanced into an hepatic vein, the contrast material is injected in a retrograde manner against the normal direction of the flow of blood (3, 19, 24, 25). With the second approach, which uses the percutaneous trans-hepatic route, an hepatic vein branch is directly injected (2, 20). In an attempt to find a more physiological approach to the study of the hepatic outflow tracts, the method of intraparenchymal deposition of contrast medium was developed by this group. Its use in small (15) and large (16, 17) laboratory animals has been previously reported. In essence, the procedure consists of the radiologic study of the vascular structures that remove an intraparenchymal deposit of medium. It is presumed that by observation of these vascular structures as they perform their intended role of draining the liver tissue, a better understanding of the function of the normal and pathologic hepatic outflow tracts may be gained. The purpose of this paper is to present the results derived from the intraparenchymal deposition of contrast medium in normal human subjects as well as in patients with hepatic and cardiac disorders. These results also include what is believed to be the first direct visual demonstration of two unusual phenomena: the role of the portal vein as an accessory outflow tract following side-to-side portacaval anastomosis and the increased transport of lymph in the efferent lymphatic system of the cirrhotic liver. An Addendum incorporates findings in the experimental animal related to a new working hypothesis concerning the etiopathogenesis of cirrhotic and cardiac ascites. Materials and Methods The method of intraparenchymal deposition of contrast medium was used in 87 instances in 62 patients. Sixteen of the 62 patients had normal liver function and served as controls. The remaining 46 had either cirrhosis of the liver or congestive heart failure. Thirty cirrhotic patients had associated ascites. Eleven patients were studied at varying intervals after the establishment of a portacaval anastomosis.