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Abstract #1774

Influence of Tissue Specific Macromolecule Baseline on the Metabolite Quantification in Human Brain at 7 Tesla

Benoit Schaller1, Lijing Xin2, Rolf Gruetter3

1Laboratory of Functional and Metabolic Imaging, Ecole Polytechnique Federale de Lausanne, Lausanne, Vaud, Switzerland; 2Department of Radiology, University of Lausanne, Lausanne, Switzerland; 3Laboratory of Functional and Metabolic Imaging, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland

The accuracy of the metabolite quantification of short echo time is challenged by the broad baseline resonances underlying the whole 1H spectrum, identified as macromolecules (MM) and characterized by short T1 and T2. Macromolecule signal was acquired with a semi adiabatic IR SPECIAL sequence in two different tissues (white matter and grey matter, n=5 for each). Small but significant changes were found in the quantification Gln, Glu and NAA which are directly link the macromolecules signal differences in the region around 2.3-2.6ppm. A general in vivo measured MM baseline seems sufficient to ensure a reliable quantification of the metabolites.

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