[Intrahepatic anatomy. Application to liver transplantation]

In transplantation of the whole liver, the variable shape of the organ can exceptionally be the source of difficulties, as in the rare cases of situs inversus. Arterial variants may be the source of great difficulties. Among the biliary variants, the low junction of the right and left hepatic ducts in the main portal pedicle, and especially the cysto-hepatic ducts (entrance of a right duct into the gallbladder or the cystic duct) are particularly important, with a frequency ranging from 2 to 15% of the cases. Right liver--left liver, or right liver--left lobe bipartition is now a well controlled technique. Right lobe, left lobe bipartition should never be performed. The left hepatic vein is attributed to the left transplant (left liver or left lobe). In case of duplication of the left vein, the terminal portion of the middle vein is attributed to the left transplant, and the continuity of the middle vein with the inferior vena cava must be reconstructed. The middle vein is always attributed to the right transplant. When the portal bifurcation is missing, usually bipartition is impossible. When the right portal vein is duplicated, the portal stem is attributed to the right liver. Duplications of right and left arteries and ducts make difficulties. A thorough preoperative investigation is necessary in case of a living donor. Cholangiography and arteriography on the back table are essential to achieve an ex vivo bipartition. The surgeon then disposes of three manoeuvres: resection of segment IV, attribution of a short segment of the main duct on the side of a biliary duplication, attribution of the main hepatic artery (or the celiac axis) on the side of a left transplant (left liver or left lobe) is possible in 86% of cases, ex vivo is possible in 95. 70% of cases. Tripartition of the liver is not yet a controlled technique.