Prospective diagnosis of choledocholithiasis.

Choledocholithiasis was detected by ultrasound in 11 of 87 patients (13%) overall, including 11 of 56 patients (20%) who had dilated ducts. Choledocholithiasis occurred with a normal caliber common bile duct in 31 of 87 patients (36%), and choledocholithiasis occurred without stones in the gallbladder in seven of 66 patients (11%). Biliary ultrasound plays a limited role in the exclusion of choledocholithiasis.