roentgenographic examination of the gallbladder and bile ducts after the introduction (orally or intravenously) of an iodine-containing contrast agent that is excreted with bile. The procedure is not applied in the case of pronounced jaundice. Cholangiography yields a clear picture of the anatomical structure and functioning of the gallbladder and bile ducts; it reveals the presence of calculi, or gallstones (cholelithiasis), inflammatory changes (cholecystitis or cholangitis), and disruption of the emptying mechanism of the bladder (dyskinesia).