Magnetic resonance cholangiography offers a noninvasive method of obta
ining images of the biliary system without the use of a contrast agent
. The diagnostic accuracy of MR cholangiography approaches that of dir
ect cholangiography, suggesting that in some patients MR cholangiograp
hy might be used either instead of endoscopic retrograde cholangiograp
hy or percutaneous transhepatic cholangiography or to direct therapeut
ic techniques. When combined with conventional MR imaging, MR angiogra
phy, MR spectroscopy, and perhaps MR-guided biopsy, a comprehensive wo
rkup of the patient with hepatobiliary disease is possible in approxim
ately 1 hour.