CHOLANGIOGRAPHY BEFORE BILIARY SURGERY - SINGLE-SHOT MR CHOLANGIOGRAPHY VERSUS INTRAVENOUS CHOLANGIOGRAPHY

PURPOSE: To compare depiction of the biliary tract with magnetic reson ance (MR) and intravenous cholangiography before biliary surgery. MATE RIALS AND METHODS: Intravenous cholangiograms and heavily T2-weighted single-shot MR images in 60 patients with biliary calculi were compare d prospectively. Images obtained with each technique were independentl y assessed for depiction of anatomy and calculi. RESULTS: The gallblad der was adequately visualized with intravenous cholangiography in 77% of patients and with MR cholangiography in 88%. Rates for visualizatio n of the common bile duct were 97% and 100%, respectively; for the cys tic duct, 27% and 75%; and intrahepatic ducts, 28% and 77%. With eithe r technique, calculi in the gallbladder were correctly predicted as so litary or multiple in approximately 80% of patients. Five cases of com mon bile duct calculi were correctly predicted with this technique, tw o cases with cystic duct calculi were depicted with only MR cholangiog raphy. CONCLUSION: Single-shot MR cholangiography may replace intraven ous cholangiography for visualization of the biliary tract. However, t he delineation of tiny gallbladder calculi and shrunken gallbladders w ith thickened bile is limited.