Mirizzi Syndrome

Mirizzi syndrome is obstruction of the common hepatic duct or common bile duct caused by an impacted gallstone in the gallbladder neck, Hartmann pouch or cystic duct.

Chronic inflammation can erode into the bile duct and create a cholecystobiliary fistula.

The major operative danger is severe distortion of Calot triangle with a markedly increased risk of common bile duct injury.

Clinically useful progression is:

• External bile duct compression without fistula
• Partial cholecystobiliary fistula
• Increasing destruction of the bile duct wall
• Complete or near complete bile duct wall loss

Presentation includes:

• Obstructive jaundice
• Right upper quadrant pain
• Fever if cholangitis develops
• Nausea or vomiting

The syndrome can mimic hilar cholangiocarcinoma because both produce proximal biliary obstruction.

MRCP: define the impacted stone and proximal biliary obstruction while determining whether bile duct distortion or fistulation is likely.

ERCP is useful when therapeutic decompression, stone management or stent placement is required.

Treat acute cholangitis first when present.

ERCP can decompress the bile duct with a stent and may facilitate removal of accessible ductal stones before surgery.

Definitive treatment requires gallbladder surgery.

External compression without major bile duct destruction

Avoid aggressive dissection around the cystic duct and common hepatic duct.

Open the gallbladder, remove the impacted stone and perform subtotal cholecystectomy when the hepatocystic triangle cannot be safely defined.

Do not pursue a conventional critical view through dense inflammatory fusion when doing so risks bile duct transection.

Cholecystobiliary fistula

Small defects with viable duct wall can sometimes be reconstructed using a cuff of gallbladder tissue or another carefully selected local repair.

Extensive bile duct wall destruction is better treated with Roux en Y hepaticojejunostomy rather than attempting a tenuous primary bile duct closure.

When preoperative anatomy is uncertain, cholangiography or direct biliary imaging during surgery can prevent misidentification.

Unexpected dense fusion of the gallbladder neck to the common hepatic duct should make the surgeon consider Mirizzi syndrome before clipping or dividing any apparent cystic duct.