Hepatology

Question 1

What are the imaging characteristics of a cholangiocarcinoma?

Answer 1

Hypovascularity with scarring and calcification

CT contrast is delivered in early (hepatic arterial) phase and delayed (portal venous) phase. Eighty percent of normal liver tissue derives its blood supply from the portal vein, but tumours generally derive their blood supply from the hepatic artery and are therefore hypervascular.

Cholangiocarcinomas are an exception as hypovascular lesions. All of the other options are hypervascular lesions (most prominent on arterial phase imaging).

Focal nodular hyperplasia will also often have a central scar and HCC will often be capsulated but may also be hypovascular in 10% of cases.

Question 2

Guidelines for referral to a liver unit following paracetamol overdose include what?

Answer 2

An arterial pH <7.3
INR >3 (or prothrombin time >50 seconds)
Oliguria
Creatinine >200 µmol/L, or
Hypoglycaemia.
Any degree of encephalopathy 48 hours after ingestion is also an indication

Question 3

Criteria for liver transplant in fulminant failure in cases of paracetamol overdose include arterial pH lower than 7.3 or all of the following:

Answer 3

Prothrombin time greater than 100 seconds
Creatinine greater than 300 µmol/L, and
Grade 3-4 encephalopathy.

Question 4

Criteria for liver transplant in fulminant failure in non-paracetamol cases include INR greater than 6.7 or prothrombin time greater than 100 seconds, or any three of the following:

Answer 4

Aetiology that is not due to hepatitis A, hepatitis B or a drug reaction
Age less than 10 years or more than 40 years
Jaundice more than seven days before encephalopathy
INR greater than 4 or prothrombin time greater than 50 seconds, and
Bilirubin greater than 300 µmol/L.