Left lobe hypoplasia of the human liver: a report of two cases.

Two cases of left lobe hypoplasia of the human liver were dissected minutely to show the intrahepatic vessels and ducts. In the left side of the round ligament, one case had a large cyst-like mass containing dilated vessels and ducts, while the other was accompanied by three rugby-ball-like parenchymal masses, each of which was covered by the peritoneum. The former specimen carried the usual Spiegel's lobe, while the latter was very small. Fascial and peritoneal fusion was evident at and around these two left lobes. In both cases the left hepatic vein showed the usual course and terminal end, segment IV was present to a greater or lesser degree. Thus, we hypothesized that, due to fascial and peritoneal fusion, membranous stricture occurred at the peripheral portions of the left portal trunk and left hepatic duct. The discussion focuses on a comparison of intrahepatic vascular configurations in four recently reported cases, including the present two livers.