Reggie Taylor1,2, Jean Thberge1,2, Peter Williamson, 1,3
1Medical Biophysics, University of Western Ontario, London, ON, Canada; 2Lawson Health Research Institute, London, ON, Canada; 3Department of Psychiatry, University of Western Ontario, London, ON, Canada
Human brain glutamate fMRS has the potential to provide dynamic information regarding normal and abnormal glutamate metabolism. With ultra-high field magnets (≤7T) increased spectral dispersion and SNR should result in more precise fMRS but how much SNR is required is not known. Using simulations of an in vivo spectrum acquired with a STEAM sequence (TE/TM 6/32ms) at 7T minimum numbers of spectra required to detect a 3% concentration change in glutamate between rest and activation were determined for various SNRs. A minimum SNR of 212 was needed to detect the 3% change when comparing only one spectrum from each state.