Intrabiliary rupture of hepatic hydatid cyst--imaging features.

Intrabiliary rupture leading to biliary obstruction is a rare but serious presentation of hepatic echinococcosis. Four such cases are presented. Imaging studies including sonography, computed tomography and/or cholangiography, done in all patients led to a definite preoperative diagnosis which was later confirmed at surgery. Biliary tree dilatation was detected in three out of four patients, hydatid contents were seen in three patients and definite cysto-biliary communication was documented in two.