Newer angiographic observations in cholangiocarcinoma.

Three new angiographic features of cholangiocarcinoma are bile duct dilatation, venous obstruction and arterio-arterial collaterals. Differentiation of the lucencies of dilated bile ducts (cylindrical in shape) from those due to metastases (spherical) is discussed. Because of its high reliability and the difficulties of operative diagnosis, angiography can play an important diagnostic role in patients with suspected cholangiocarcinoma.