Minor variations in the external lobation of the liver are common but clinically insignificant.
Accessory hepatic ducts are sometimes seen. An awareness of their possible presence is important for the surgeons operating in this area. Usually these accessory ducts are narrow channels passing from the right lobe of the liver directly into the gallbladder.
The gallbladder is also subject to certain congenital malformations which has little clinical importance. These malformations include absence, complete duplication or partial subdivision of the gallbladder.
The most serious anomaly of the extrahepatic biliary apparatus is extra-hepatic biliary atresia. This anomaly has been reported to occur in 1/15,000 live births. The atresia occurs due to failure of recanalization, resulting in persistence of the solid stage of duct development. In 80 to 85 % of the cases, the atresia is extensive and involves most of the common bile duct and cystic duct, and sometimes the gallbladder as well. However, in 15 to 20 % of the cases the atresia may be limited to only a small part of the common bile duct. The infants with congenital biliary atresia develop a steadily increasing jaundice after birth. The infants suffering from extensive
biliary atresia usually die unless a liver transplant is performed. However, cases of congenital atresia of a limited part of the common bile duct can be saved by surgical procedures