Parameter optimization and calibration of 19F magnetic resonance imaging at 1.5 Tesla.

Fluorine-19 magnetic resonance imaging is limited by the fact that acquisition times are long and that high concentrations must be used in order to obtain good signal to noise. A significant improvement in signal to noise ratio may be brought about by the addition of Gd-DTPA, a paramagnetic agent which shortens T1. Images of phantoms containing trifluoroacetic acid (TFA) doped with Gd-DTPA were obtained using a standard spin echo sequence in a 1.5 T field. Interpulse times (TR and TE) and Gd-DTPA concentrations were optimized to yield maximum signal to noise ratios. The use of fast-field-echo scans to image fluorine is also demonstrated. Signal averaging successive FFE scans yields good signal to noise and resolution and may find clinical applicability in imaging areas subject to motion.