A New Paradigm for High-Sensitivity 19F Magnetic Resonance Imaging of Perfluorooctylbromide

In the present work, the NMR properties of perfluorooctylbromide are revisited to derive a high-sensitivity fluorine MRI strategy. It is shown that the harmful effects of J-coupling can be eliminated by carefully choosing the bandwidth of the 180 degrees pulses in a spin-echo sequence. The T-2 of the CF3 resonance of the molecule is measured using a multispin-echo sequence and shown to dramatically depend on the interpulse delay. Following these observations, an optimized multispin-echo imaging sequence is derived and compared with short TE/pulse repetition time gradient echo and chemical shift imaging sequences. The unparalleled sensitivity yielded by the multispin-echo sequence is promising for future applications, in particular for targeted contrast agents such as perfluorooctylbromide nanoparticles. Magn Reson Med 63: 1119-1124,2010. (C) 2010 Wiley-Liss, Inc.