Mirizzi's syndrome. An uncommon cause of biliary obstruction.

An uncommon cystic-duct anomaly characterized by a course parallel to the common hepatic duct or contained in a sheath with the common hepatic duct over a significant distance can allow cystic-duct stones to occlude the common hepatic duct by extrinsic pressure. This condition is appropriately referred to as Mirizzi's syndrome. One such case is described in the present study. Recognition of this and other biliary anomalies is critical to safe operative management of calculous biliary disease.