Zero-quantum filter offering single-shot lipid suppression and simultaneous detection of lactate, choline, and creatine resonances

A zero-quantum (ZQ) filter offering single-shot lipid suppression and provi ding for simultaneous detection of the lactate methyl doublet (1.3 ppm) and nonoverlapping singlets including choline (Cho, 3.2 ppm) and creatine (Cr, 3.0 ppm) is described. Filtering is provided by soft mixing and reading pu lses (RFmix, RFrd) that are selective for the lactate methine quartet (4.1 ppm), Cho, and Cr resonances but exclude the 1.3 ppm lactate component and overlapping lipids. Surrounding RFmix and RFrd are magnetic field gradient pulses of equal magnitude but opposite signs to enable the rephasing of the zero-quantum lactate coherence and the creation of a stimulated echo for s inglets within the pulse passbands. The sequence is designed to retain half the original lactate and singlet signal intensities. Theoretical predictio ns were confirmed experimentally at 1.5T using phantom acquisitions. The li pid suppression factor was measured to be over 10(3). (C) 2001 Wiley-Liss, Inc.