On the CT the liver looks quite normal.

However if you look at the common bile duct in the pancreatic head you will notice the soft tissue density.

The differential diagnosis would include an impacted stone or cholangiocarcinoma, but since this patient had no obstruction, it was thought to be the result of bile wall thickening.

The gallbladder wall is also thickened.

http://www.radiologyassistant.nl/en/49e17de25294d#a49e4e5125f1b4

arrow=irregular thickening of common bile

duct walls

http://www.radiologyassistant.nl/en/49e17de25294d#a49e4e5125f1b4

CT signs:

ERCP showed irregular borders of bile ducts(arrow head)and the band like structures(straight arrows) of the intra hepatic ducts with the paucity of side branches corresponding to apperance
seen in A.

thickening of right and left hepatic ducts(arrows).

heterogenous enhancement of both lobes of the liver caused by cirrhosis or peri portal fibrosis.

(A)

open arrow=long segment of dilated duct without a normal branching pattern,this appearance of

cholangiographic pruned tree pattern. 1-In the evaluation of patients with PSC, CT has a role complementary to that of cholangiography. Computed tomography is not as sensitive as cholangiography for detecting the subtle mucosal abnormalities of the bile ducts, and therefore it should not be used as a screening examination in patients suspected of having PSC. However, the multiple, tight bile duct strictures in PSC can preclude adequate evaluation of the intrahepatic bile ducts with cholangiography; it is in this group of patients that CT can be helpful in evaluating the extent of disease.

2-The CT appearance characterised by presence of multiple areas of intra hepatic biliary dilatation in both lobes without any apparent connection to central ducts(skip dilatation).

Reference:BiblioMed Textbook-Computed Body Tomography

multiple,small cystic peripheral structures(arrows)

open arrow=focal area of dilatation.
Reference:BiblioMed Textbook-Computed Body Tomography