Ultrasonographic evaluation of ascaris in the biliary tract.

Ascaris in the biliary tract may cause cholecystitis and obstruction of the common bile ducts. Two cases are presented where worms that were identified in the common bile duct caused obstructive jaundice. The image of the ascaris is typical in its morphology and movement. Ultrasonography is useful in the identification of this parasite in the biliary tract where other conventional radiological methods are frequently unsatisfactory.