Biliary necrosis
Biliary necrosis refers to the death of the intra-hepatic bile ducts epithelium commonly seen as a complication of hepatic artery thrombosis.
Pathology
Different from the liver parenchyma that has dual supply, portal vein and hepatic artery, the intrahepatic biliary ducts are exclusively supplied by peribiliary plexus, which branches from the hepatic artery . The extra-hepatic ducts have multiple extra-hepatic blood supplies making them less vulnerable to develop necrosis .
Therefore, any cause leading to occlusion of the hepatic artery may lead to biliary necrosis:
- hypercoagulable states
- vasculitis
- embolic disease (e.g. atrial fibrillation)
- traumatic laceration/dissection of the hepatic artery
- liver transplant complication
- iatrogenic causes
- after transarterial chemoembolization (TACE)
- incidental ligation of the hepatic artery while other hepatobiliary surgeries
Radiographic features
Fluoroscopy
ERCP may show dilated bile ducts with diffuse wall irregularities with some contrast penetration/cavitation towards the parenchyma .
CT
Biliary infarct will manifest as wall irregularities and beading dilatation appearances of the intrahepatic bile ducts associated with marked surrounded hypoattenuation. Multiple cavitations/bile lakes are also characteristic in advanced necrosis, the presence of gas is frequent and not necessarily represents infection .
Differential diagnosis