Reproducibility of Glutamate Measurement in the Human Brain with 1H-MRS at 7T: Evaluation of the SLASER Sequence

Anouk Marsman¹, Vincent Boer², Martijn Van den Heuvel³, Peter Luijten², Hilleke Hulshoff Pol³, Dennis Klomp², Ren Mandl³

1H-MRS at 7T can be used to accurately determine glutamate in the human brain. A sLASER sequence has been developed, using field focusing at short TE resulting in twice as much signal as can be obtained by using STEAM. To assess reliability and reproducibility of sLASER compared to STEAM, eight subjects were scanned twice with both sequences, in the frontal and occipital lobe. sLASER has significant intraclass correlations for glutamate in both locations, STEAM did not show any significant correlations. Thus, sLASER is a reliable method to obtain glutamate in the human brain at higher accuracy than physiological variability.