There is no participant enrolled in this study since developing this trial and other cholangiographic techniques are more available in our institute.

The reason for this study is to see if a new radiologic technique called computerized tomographic cholangiography (CT cholangiography) could be helpful to demonstrate the bile ducts features and measure the amount of space of bile duct canals that should be filled with bile fluid. It may be useful to find out how well these findings correlate with the previously known clinical predictors in term of the clinical outcomes that will happen in the future for patients with primary sclerosing cholangitis (PSC).

Prognostic models, which have been produced based on clinical, histological and biochemical feature, are useful in predicting survival and determining timing for liver transplantation. Preliminary feasibility studies in patients with PSC using high resolution CT with a contrast agent (CT cholangiography), has shown excellent depiction of bile ducts. CT cholangiography also has the potential to allow quantification of intraductal volume by using sophisticated computer programs. This assessment may be an important clinical feature to assess disease severity and progression.The information about cholangiographic features could be important for therapeutic decisions (e.g., in determining the usefulness of balloon dilatation or stenting for a dominant extrahepatic duct stricture), for counseling patients, and for therapeutic trials in stratifying patients and assessing efficacy of treatment.

Inclusion Criteria:

• Adult males or females, age 18-70 (inclusive) with suspected PSC.
• Serum carbohydrate antigen 19-9 (CA19-9) level in normal range (obtained within the previous year), or if greater than normal, the patient requires a negative cytologic or histologic evidence for cholangiocarcinoma within prior 3 months.
• Sexually active female patients of childbearing potential must be evaluated for pregnancy. A pregnancy test obtained at entry prior to the initiation of treatment must by negative. Female patient must not be breast-feeding.
• Renal function: a creatinine less than 2.0 mg/dL or a diabetic patient with a creatinine less than 1.5 mg/dL.

Exclusion Criteria:

• Evidence of cholangiocarcinoma
• Pregnancy or breast feeding
• History of allergy to iodinated contrast agents or morphine
• Renal impairment as defined as known renal disease, a creatinine higher than 2.0 mg/dL or a diabetic patient with a creatinine higher than 1.5 mg/dL.
• Any known pre-existing medical condition that could interfere with the patient's participation in and completion of the study such as significant cardiovascular dysfunction or chronic obstructive pulmonary disease requiring specific therapy.