Cholestasis refers to any condition that impairs the normal flow of bile from the liver to the duodenum. It can be caused by problems within the liver itself, called intrahepatic cholestasis, or by physical obstruction of the bile ducts outside the liver, called extrahepatic cholestasis. On ultrasound, the most important task is distinguishing between these two types, as extrahepatic obstruction typically shows dilated bile ducts while intrahepatic cholestasis usually does not. Common causes of extrahepatic cholestasis include gallstones, pancreatic tumors, and bile duct strictures, while intrahepatic cholestasis can result from hepatitis, drug reactions, and pregnancy-related conditions.
Sonography Term