Echo acquisition during frequency-selective pulse trains for proton spectroscopy of metabolites in vivo.

Suppression of water and fat in proton spectra of rat skeletal muscle was achieved by acquisition of the spin echoes formed in the steady state after a series of frequency-selective composite pulses of constant amplitude, phase, and interpulse interval. The method enables observation of lactate in the presence of fat without resorting to difference spectroscopy, and on spectrometers which permit data acquisition immediately prior to a pulse, enables much faster data accumulation compared to standard echo sequences.