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.