Broadband decoupled, 1H-localized 13C MRS of the human brain at 4 Tesla.
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.
Clinical Research Center and Center for MR Research, Department of Radiology, Minneapolis, MN 55455, USA.
R
R
Gruetter
G
G
Adriany
H
H
Merkle
P M
PM
Andersen
D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000032:analysis; D001923:Brain Chemistry; D018698:Glutamic Acid / Q000032:analysis; D005973:Glutamine / Q000032:analysis; D006801:Humans; D007294:Inositol / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*
D005973:Glutamine; D001224:Aspartic Acid; D018698:Glutamic Acid; D007294:Inositol; C000179:N-acetylaspartate