Quantification of in vivo 31P NMR brain spectra using LCModel

Quantification of 31P NMR spectra is commonly performed using line‐fitting techniques with prior knowledge. Currently available time‐ and frequency‐domain analysis software includes AMARES (in jMRUI) and CFIT respectively. Another popular frequency‐domain approach is LCModel, which has been successfully used to fit both 1H and 13C in vivo NMR spectra. To the best of our knowledge LCModel has not been used to fit 31P spectra. This study demonstrates the feasibility of using LCModel to quantify in vivo 31P MR spectra, provided that adequate prior knowledge and LCModel control parameters are used. Both single‐voxel and MRSI data are presented, and similar results are obtained with LCModel and with AMARES. This provides a new method for automated, operator‐independent analysis of 31P NMR spectra. Copyright © 2015 John Wiley & Sons, Ltd. LCModel can successfully fit in vivo 31P spectra (both single‐voxel and MRSI data) when the appropriate basis set and the differences in the apparent linewidths for each metabolite are taken into account. An example of an LCModel‐fitted 31P spectrum (acquired from the human brain at 3 T) is shown here.