[Management of a biliary cyst disclosed prenatally. Apropos of 2 cases].

Two cases of prenatal detection of congenital biliary cysts are reported. Prenatal and postnatal ultrasonography demonstrate a solitary sonolucent cystic lesion. The differential diagnosis in fetus and infant includes any abdominal cystic lesions: ovarian cyst, duplication cyst, cystic lymphangioma, choledochal cyst and other congenital cysts of the liver. In opposite to the difficulty of diagnosis, the choice for treatment is easy: surgery is the only way to allow histologic diagnosis and to avoid any relapse or complications.