title: In vivo 1H NMR spectroscopy of the human brain at 7 T.
abstract: In vivo 1H NMR spectra from the human brain were measured at 7 T. Ultrashort echo-time STEAM was used to minimize J-modulation and signal attenuation caused by the shorter T2 of metabolites. Precise adjustment of higher-order shims, which was achieved with FASTMAP, was crucial to benefit from this high magnetic field. Sensitivity improvements were evident from single-shot spectra and from the direct detection of glucose at 5.23 ppm in 8-ml volumes. The linewidth of the creatine methyl resonance was at best 9 Hz. In spite of the increased linewidth of singlet resonances at 7 T, the ability to resolve overlapping multiplets of J-coupled spin systems, such as glutamine and glutamate, was substantially increased. Characteristic spectral patterns of metabolites, e.g., myo-inositol and taurine, were discernible in the in vivo spectra, which facilitated an unambiguous signal assignment.
authors.affiliation: Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota 55455, USA. ivan@cmrr.umn.edu
authors.forename: I
authors.initials: I
authors.lastname: Tkác
authors.forename: P
authors.initials: P
authors.lastname: Andersen
authors.forename: G
authors.initials: G
authors.lastname: Adriany
authors.forename: H
authors.initials: H
authors.lastname: Merkle
authors.forename: K
authors.initials: K
authors.lastname: Ugurbil
authors.forename: R
authors.initials: R
authors.lastname: Gruetter
mesh_terms: D000328:Adult; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology*; D001931:Brain Mapping; D004734:Energy Metabolism / Q000502:physiology*; D006801:Humans; D007089:Image Enhancement; D009682:Magnetic Resonance Spectroscopy; D018377:Neurotransmitter Agents / Q000378:metabolism*; D012016:Reference Values
chemical_list: D018377:Neurotransmitter Agents