In the presence of obstructive jaundice, irregular strictures high in the common hepatic duct are usually due to bile duct cancer or to metastatic infiltration from other malignant tumours. Postoperative strictures and a variety of benign tumours also occur in this region but usually have a distinctive appearance on retrograde cholangiography. Obstruction of the bile duct due to an impacted calculus in Hartmann's pouch (Mirizzi syndrome) and sclerosing cholangitis also have characteristic radiological appearances and are supported by the coexistence of gallstones and inflammatory bowel disease respectively.
