Premium
Improved quantification of in vivo 1 H NMR spectra by optimization of signal acquisition and processing and by incorporation of prior knowledge into the spectral fitting
Author(s) -
De Graaf A. A.,
Bovée W. M. M. J.
Publication year - 1990
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.1910150212
Subject(s) - spectral line , pulse sequence , nuclear magnetic resonance , pulse (music) , spins , in vivo , chemistry , nmr spectra database , signal (programming language) , metabolite , biological system , analytical chemistry (journal) , physics , computer science , optics , chromatography , astronomy , detector , biology , programming language , condensed matter physics , biochemistry , microbiology and biotechnology
Quantification of localized in vivo brain 1 H spectra is in general very difficult due to excessive spectral overlap. In addition, intensity distortions may result from the effects of the NMR pulse sequence on the spins. This paper describes an approach to solving these problems. It comprises optimization of the pulse sequence; correction of the experimental lineshape; determination of intensity distortions, of relative line positions, and of linewidths using model solutions; and incorporation of the thus obtained prior knowledge into a nonlinear least‐squares spectral fitting procedure. This approach resulted in greatly improved accuracy, precision, and reliability of the quantitation of our in vivo spectra of rat brain, and enabled us to estimate absolute metabolite concentrations. © 1990 Academic Press, Inc.