MR and MRCP in the evaluation of primary sclerosing cholangitis: current applications and imaging findings.

Primary sclerosing cholangitis is a progressive cholestatic disease of unknown etiology leading to cirrhosis and liver failure. Several imaging modalities have been used to study this disease, including ultrasonography, computed tomography and hepatobiliary scintigraphy, but accurate diagnosis was found to be best made with endoscopic retrograde cholangiopancreatography or direct cholangiography. However, these 2 methods are invasive and may produce serious complications. Magnetic resonance cholangiopancreatography is a noninvasive imaging technique that has become very useful for diagnosing primary sclerosing cholangitis. Contrast enhanced magnetic resonance imaging provides pertinent information of extraductal abnormalities in addition to biliary ductal changes.