Comparison of single voxel brain MRS AT 3T and 7T using 32-channel head coils.

Purpose: The purpose of this study was to compare magnetic resonance spectroscopy (MRS) of three different regions of the human brain between 3 and 7 Tesla, using the same subjects and closely matched methodology at both field strengths.

Methods: A semi-LASER (sLASER) pulse sequence with TE 32ms was used to acquire metabolite spectrum along with the water reference at 3T and 7T using similar experimental parameters and hardware at both field strengths (n=4 per region and field). Spectra were analyzed in LCModel using a simulated basis set.

Results: Signal-to-noise ratio (SNR) at 7T was higher compared to 3T, and linewidths (in ppm) at both field strengths were comparable in ppm scale. Of the 13 metabolites reported in the paper, most metabolites were measured with higher precision at 7T in all three regions.

Conclusion: The study confirms gains in SNR and measurement precision at 7T in all three representative brain regions using the sLASER pulse sequence coupled with a 32-channel phased-array head coil.