Anatomical features of liver in situs inversus.

The hepatic veins and the intrahepatic branches of both the portal vein and the hepatic artery have been dissected and studied in three specimens of liver obtained from bodies in situs inversus. The position of the hepatic veins was found generally to correspond to the intersegmental scissure planes of the liver. The intrahepatic branches of the portal vein were found to delineate the subdivision of the liver into lobes, segments and subsegments which correspond to the 'mirror image' of the normal liver. The arterial irrigation derives from the mirror image constituting peculiar patterns in each of the specimens. In the first specimen, the left hepatic artery irrigates the superior subsegments of the right lobe, which depends on the right branch of the portal vein. In the second specimen, a voluminous anastomotic intrahepatic channel was noted between the right hepatic artery and the subsegmental posterior inferior branch of the left hepatic artery. In the third specimen, the arterial branch which irrigated the inferior subsegments of the right lobe also contributed to the irrigation of the superior lateral subsegment.