Purpose: To qualitatively and quantitatively compare gadoxate-enhanced T 1-weighted MR cholangiography at magnetic field strengths of 1.5 T and 3.0 T.
Materials and methods: A total of 40 patients with a non-dilated biliary system were retrospectively included in the study. T 1-weighted MR cholangiography 20 min after IV administration of 0.025 mmol/kg gadoxate (Primovist) was performed in 20 patients at 1.5 T and in another 20 patients at 3.0 T. Contrast-to-noise ratios (CNR) of the biliary system (common bile duct - CBD, right hepatic duct - RHD, left hepatic duct - LHD) compared to the periductal tissue were measured. Two radiologists also qualitatively assessed the visibility of the intrahepatic and extrahepatic biliary system using a six-point rating scale. The Mann-Whitney U-test and Pearson's correlation coefficient were used for statistical analysis.
Results: The CNRs of the intrahepatic and extrahepatic hepatic bile ducts were significantly higher at 3.0 T. Qualitative analysis showed a significant superiority for 3.0 T in the delineation of the intrahepatic biliary system (RHD, LHD, segmental ducts).
Conclusion: Gadoxate-enhanced T 1-w MR cholangiography at 3.0 T offers better delineation of the intrahepatic biliary system in comparison to imaging at 1.5 T.