title: Quantification of the neurochemical profile using simulated macromolecule resonances at 3 T.
abstract: The broad resonances underlying the entire (1) H NMR spectrum of the brain, ascribed to macromolecules, can influence metabolite quantification. At the intermediate field strength of 3 T, distinct approaches for the determination of the macromolecule signal, previously used at either 1.5 or 7 T and higher, may become equivalent. The aim of this study was to evaluate, at 3 T for healthy subjects using LCModel, the impact on the metabolite quantification of two different macromolecule approaches: (i) experimentally measured macromolecules; and (ii) mathematically estimated macromolecules. Although small, but significant, differences in metabolite quantification (up to 23% for glutamate) were noted for some metabolites, 10 metabolites were quantified reproducibly with both approaches with a Cramer-Rao lower bound below 20%, and the neurochemical profiles were therefore similar. We conclude that the mathematical approximation can provide sufficiently accurate and reproducible estimation of the macromolecule contribution to the (1) H spectrum at 3 T.
authors: Laboratory of Functional and Metabolic Imaging, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland.
authors: Benoît
authors: B
authors: Schaller
authors: Lijing
authors: L
authors: Xin
authors: Cristina
authors: C
authors: Cudalbu
authors: Rolf
authors: R
authors: Gruetter
mesh_terms: D001921:Brain / Q000378:metabolism*; D018698:Glutamic Acid / Q000032:analysis; D005973:Glutamine / Q000032:analysis; D006801:Humans; D046911:Macromolecular Substances / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008433:Mathematics; D005680:gamma-Aminobutyric Acid / Q000032:analysis
chemical_list: D046911:Macromolecular Substances; D005973:Glutamine; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid