Bile duct calculi in patients with primary sclerosing cholangitis

PURPOSE: To determine the imaging appearance and frequency of detection of bile duct calculi in patients with primary sclerosing cholangitis. MATERIALS AND METHODS: Images (169 computed tomographic [CT] scans, 155 sonograms, and 109 cholangiograms) of 189 patients with primary sclerosing cholangitis, five of whom were prospectively included, were reviewed. Pathologic records were reviewed for proof of the presence of calculi. RESULTS: Bile duct calculi were visualized on images in 14 (7.6%) of the 184 retrospective patients and in all five of the prospective patients. The presence of calculi was confirmed with pathologic or imaging findings in 19 patients, in whom calculi were visible on 16 of 18 CT scans, 15 of 19 sonograms, and 14 of 17 cholangiograms. Calculi were in the intrahepatic ducts in 11 patients and in the intra- and extrahepatic bile ducts in eight patients. At CT, calculi appeared as foci of faint high attenuation or as coarse calcifications in nondilated or variably dilated ducts. At sonography, they appeared as unique echogenic casts with variable posterior acoustic shadowing or as discrete, echogenic, variably shadowing foci in variably dilated ducts. Calculi were depicted at cholangiography as rounded filling defects. CONCLUSION: Intrahepatic bile duct calculi are present in approximately 8% of patients and can have a unique imaging appearance.