Sonography of the distal cystic duct.

This prospective study of 139 patients was performed for evaluation of the normal and abnormal distal cystic duct and cystic duct remnant after cholecystectomy. The normal distal cystic duct could be demonstrated in 51% of the patients with normal common bile duct and normal gallbladder. The average diameter of the normal distal cystic duct was 1.8 mm. In 95% of the patients, the distal cystic duct was located posterior to the common bile duct and, in 5% of the patients, anterior to the common duct. Echoes produced by cystic duct insertion into the common bile duct occasionally can be mistaken for stones in the common bile duct. These echoes, however, are not associated with acoustic shadowing. Sludge and stones could be demonstrated in the distal cystic duct as well as in the cystic duct remnant after cholecystectomy.