Fast 19F-NMR imaging in vivo using FLASH-MRI.

The goal of this study was the development of a method that allows the acquisition of chemical shift selective 19F NMR images within a short measuring time. A train of small tip angle frequency selective pulses, each followed by a dephasing gradient of random strength, was used as a presaturation experiment for the suppression of the unwanted chemical shift components. Imaging was performed after presaturation using a SNAPSHOT-FLASH experiment. The acquisition time for a 64 x 128 image including the presaturation experiment amounted to only 470 ms. The sequence was applied in a 4.7 Tesla magnet to perform a longitudinal pharmacological study on the clearance of perfluoroocytlbromide (PFOB) in the liver and spleen of rats.