mirizzi syndrome
Mirizzi syndrome refers to an uncommon phenomenon that results in extrinsic compression of an extrahepatic biliary duct from one or more calculi within the cystic duct or gallbladder. It is a functional hepatic syndrome but can often present with biliary duct dilatation and can mimic other hepatobiliary pathologies such as cholangiocarcinoma .
Clinical presentation
Patients may present with recurrent episodes of jaundice and cholangitis. It can be associated with acute cholecystitis.
Fistulae can develop between the gallbladder and the common duct, and the stone may pass into the common duct.
Pathology
Risk factors
A low insertion of the cystic duct into the common bile duct as well as a tortuous cystic duct are thought to be risk factors.
Classification
Csendes classification
Management decisions are dependent on the type of Mirizzi syndrome.
- type I: extrinsic compression of the common hepatic duct (CHD)
- type Ia: by impacted gallstone in the gallbladder neck or cystic duct
- type Ib: if cystic duct is absent
- type II: erosion of CHD wall and formation of cholecystocholedochal fistula (up to one-third CHD wall circumference is involved)
- type III: up to two-thirds of CHD wall circumference is involved in a cholecystocholedochal fistula
- type IV: entire CHD wall is involved in a cholecystocholedochal fistula
- type V: any of the above with cholecysto-enteric fistula
Radiographic features
ERCP
The stricture is smooth and often concave to the right.
CT
The gallbladder wall may be diffusely thickened and may enhance with contrast.
MRI
MRCP classically shows a large impacted gallstone in the gallbladder neck or cystic duct, or signs of inflammed gallbladder causing proximal dilatation of the extra and intrahepatic biliary tree, with distal gradual tapering of the extrahepatic biliary duct caliber to the site of obstruction.
History and etymology
It was first described by Pablo Luis Mirizzi (1893-1964), an Argentinian surgeon in a paper from 1940, although 1948 is often quoted, as in this year he published a paper in which it became widely-known . Mirizzi performed the first operative cholangiogram in 1931. He was named a Master Surgeon (Cirujano Maestro) in 1956 by the Argentinian Surgeons Society (Sociedad Argentina de Cirugía) .