Gruetter R, Adriany G, Merkle H, Andersen P M
Clinical Research Center and Center for MR Research, Department of Radiology, Minneapolis, MN 55455, USA.
Magn Reson Med. 1996 Nov;36(5):659-64. doi: 10.1002/mrm.1910360503.
Broadband proton decoupling of the entire 13C spectrum was possible within power absorption guidelines and resulted in the detection of narrow (as low as 2-3 Hz), natural abundance signals from metabolites such as myo-inositol, glutamate, N-acetyl-aspartate, and glutamine from 72 cm3 volumes in the human brain. To overcome the chemical shift displacement error, three-dimensional localization on the 1H z magnetization was combined with polarization transfer. Efficiency of the heteronuclear localization method was demonstrated by the elimination of all scalp lipid resonances. A signal-to-noise ratio of 5:1 for 0.07 mM [13C] was achieved in 12 min, which is approximately a fivefold improvement over the sensitivity reported at 2.1 Tesla.
