Amplitude- and frequency-modulated pulses, known as adiabatic pulses, can induce uniform flip angles in the presence of extremeB1inhomogeneity, which makes them advantageous forin vivosurface-coil studies. This paper describes the conversion of conventional (square pulse-based) spectral-editing sequences into their adiabatic counterparts. Eight adiabatic homo- and heteronuclear sequences are experimentally evaluated for lactate editing. For homonuclear lactate editing, gradient-enhanced multiple-quantum-coherence filtering provides the best overall performance (100% signal recovery with excellent water and lipid suppression in a single acquisition). For heteronuclear [3-13C]lactate editing, gradient-enhanced heteronuclear multiple-quantum-coherence filtering provides the best suppression of unwanted signals in a single acquisition, whereas J-modulated spin-echo sequences yield maximum sensitivity.
Bibliographical noteFunding Information:
This research was supported by NIH Grants RR08079, CA50703, and HL32427.