Courvoisier's law is related to:

Courvoisier's Law In Obstruction of the common bile duct due to a stone, distention of gall bladder seldom occurs; the organ usually is shriveled. If there is no disease in the gall bladder and the obstruction is due to cancer of ampulla, pancreas or bile duct, then gall bladder will be distended. Exceptions to courvoisier's Law Double impaction of stones i.e. one in the cystic duct and other in CBD. Oriental cholangiohepatitis Pancreatic calculus obstructing the ampulla of Vater Mucocele due to stone in the cystic duct