Computed tomographic diagnosis of obstructive jaundice in the absence of intrahepatic ductal dilatation

Six patients with obstructive jaundice had computed tomography (CT) scans showing a dilated extrahepatic biliary tree in the absence of intrahepatic ductal dilatation. Dilated extrahepatic bile ducts were most easily identified by means of intravenous injection of urographic contrast material, which permitted them to be seen as low density structures. Findings in these patients emphasize that (1) demonstration of dilated intrahepatic bile ducts is not a prerequisite for the CT diagnosis of obstructive jaundice and (2) careful CT evaluation of the extrahepatic biliary tree is necessary to identify patients with isolated dilatation of the common hepatic or common bile duct.