Biliary malformation

Antenatally, US is a useful tool for detection of biliary malformations. The presence of a cystic structure localized at the hepatic hilum can occur in BA or may present as a choledochal cyst. However, if this cyst is small and anechoic it will be more suggestive of an atresia of the biliary canals, while the presence of an echoic cyst that gradually increases in size supports a choledochal cyst. The specificity of these US findings with BA, however, is not well known (Kim et al. 2000). 

Lobar agenesis In most cases, agenesis affects the right lobe. This very rare abnormality is mostly associated with other congenital malformations, especially of the biliary system. The unaffected liver lobe will generally develop compensatory hypertrophy. (22, 40, 49)... 

Benign biliary microhamartomas (= Meyenburg s complex) were described by H. von Meyenburg in 1918. They consist of small cysts developing from dilatations of the small (interlobular) bile ducts and are surrounded by fibrous stroma. The cysts are remnants of ductal plate malformations. Occasionally, typical ductal plates can also be detected. The hamartomas can reach a diameter of up to 0.5 (-1.0) cm. (s. fig. 32.18) Macroscopically,... 

Hepatic cysts can also be part of polycystic liver disease, an autosomal dominant disorder often found in association with renal polycystic disease (van Sonnenberg et al. 1994). It is due to a ductal plate malformation of the small intrahepatic bile ducts, which loses communication with the biliary tree. It is characterized by the presence of multiple, sometimes innumerable cysts ranging in size from less than 1 cm to more than 12 cm spontaneous intracystic hemorrhage, infection, and rupture may occur. Usually, patients with autosomal dominant polycystic liver disease are asymptomatic and liver dysfunction occurs rarely... 

A choledochal cyst is a rare congenital dilation of the hepatic duct of the liver and is due to a ductal plate malformation of the large hile ducts. They maintain continuity with the biliary tree. These cysts can he intrahepatic and/or extrahepatic (Kim et al. 1995). 

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