Comparison of Spectral Fitting Methods for Overlapping J-Coupled Metabolite Resonances

摘要

There is increasing interest in the use of two dimensional J-resolved spectroscopic acquisition (multi-echo) methods for in vivo proton MR spectroscopy due to the improved discrimination of overlapping J-coupled multiplet resonances that is provided. Of particular interest is the potential for discrimination of the overlapping resonances of glutamate and glutamine. In this study, a new time-domain parametric spectral model that makes use of all available data is described for fitting the complete two-dimensional multi-echo data, and the performance of this method was compared with fitting of one-dimensional spectra obtained following averaging multi-echo data (TE-averaged) and single-TE PRESS acquired spectra. These methods were compared using data obtained from a phantom containing typical brain metabolites and a human brain. Results indicate that improved performance and accuracy is obtained for the two-dimensional acquisition and spectral fitting model.