What is the best fruit juice to use as a negative oral contrast agent in magnetic resonance cholangiopancreatography?

Highlights: • The Fe content does not influence the shortening of the T2 relaxation time. • The shortening of T2 relaxation time is dependent on the juice Mn concentration. • The minimum concentration of Mn to suppress the gastrointestinal signal is 1 mg/dl. • All commercially available juices can reach this concentration. • Using FIESTA sequence a Flip Angle of 90° is recommended for biliary tree study. -- Abstract: To identify, in vitro, the best fruit juice to use as oral contrast agent in magnetic resonance cholangiopancreatography (MRCP) and to test, in vivo, the best natural juice and the new parameters in MRCP sequences identified in vitro.