What is the best fruit juice to use as a negative oral contrast agent in magnetic resonance cholangiopancreatography?. Issue 3 (March 2019)

• Record Type: Journal Article
• Authors: Renzulli, M.; Biselli, M.; Fabbri, E.; Caretti, D.; Sergenti, A.; Modestino, F.; Giannone, F.A.; Storchi, M.; Pierotti, L.; Golfieri, R.
• Is Part Of: Clinical radiology. Volume 74:Issue 3(2019)
• Page Start: 220
• Page End: 227
• Publication Date: 2019-03
• Subjects: Medical radiology -- Periodicals; Radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiology -- Periodicals; Societies, Medical -- Periodicals; Medical radiology; Radiotherapy; Electronic journals; Periodicals; 616.0757
• DOI: 10.1016/j.crad.2018.11.005
• Languages: English
• ISSNs: 0009-9260

Abstract

Abstract : Aim: 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 . Materials and methods: The in vitro evaluations consisted of measuring the T2 values of a pure solution of manganese (Mn) and iron (Fe) at different concentrations, measuring the content of Mn and Fe in five commercial juices and their T2 relaxation times, and identifying the optimal juice dilution for suppressing the gastrointestinal fluid signal. The new parameters of MRCP sequences were tested in vivo . Results: Manganese alone strongly influenced the shortening of the T2 values ( p= 0.004). The T2 value with an echo time (TE) of ≥1, 000 ms enabled sufficient intestinal fluid suppression in the case of high juice dilution. A flip angle of 90° maximised the differences between the high signal from static fluids, such as the bile and the fluid in the gastrointestinal tract, using fast imaging employing steady-state acquisition (FIESTA) sequences ( p< 0.001). Conclusion: The shortening of the T2 relaxation time depended only on the Mn concentration. All the commercial juices had an Mn concentration sufficient to suppress the gastrointestinal fluid signal using long TE sequences. The oral ingestion of commercial juice before MRCP was enough to suppress the signal from the gastrointestinal fluids, regardless of its dilution after ingestion. When using FIESTA sequences, a flip angle of 90° allowed the best suppression of gastrointestinal fluid signals. 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.