Intrabiliary rupture of hepatic hydatid cyst: sonographic and cholangiographic appearances.

Sonographic and cholangiographic appearances of confirmed intrabiliary rupture of a hepatic hydatid cyst were studied in 15 cases. Sonographic findings included liver cyst in all cases; nonshadowing echogenic structures in the dilated biliary tree representing hydatid material, such as fragmented membranes, sand, matrix, and daughter vesicles, in eight cases; and loss of continuity of the cyst wall adjacent to the bile duct representing the site of communication in seven cases. Cholangiographic findings were as follows: filling defects of varying size and shapes in the dilated biliary tree in 13 cases, and changing shape and position of these filling defects in three of them; and leakage of contrast medium into the cyst cavity in 12 cases. Intrabiliary rupture of hepatic hydatid cyst was suggested by sonography in 10 cases (66.7%) and at cholangiography in 13 cases (86.6%). We conclude that a joint application of sonography and endoscopic cholangiography is mandatory for proper preoperative evaluation of this disorder.