Detection of γ-aminobutyric acid level in vivo with MEGA-PRESS sequence at 1.5 Tesla

γ-aminobutyric acid (GABA) is well-known for its low signal-to-noise ratio in vivo measurement with magnetic resonance spectrum (MRS) technique, especially detecting it at 1.5 Tesla scanners. The objective of this study is to achieve γ-aminobutyric acid concentration of cerebral regions with MEGA-PRESS sequence using a 1.5 T clinical MR scanner. MEAG-editing inserted into the point resolved spectroscopy sequence (PRESS) methods is a J-difference editing. It can detect weakly-coupled signals in GABA and make it visible by subtracting spectrums. In vivo experiments, a single voxel was located in the right Semiovale center of all four participates (two males, two females). MEGA-editing and nonrefocused spectrums were acquired separately by Edit-On/Off technique. The GABA peaks at 3.0 ppm were quite obviously seen, proving the favorable editing efficiency. jMRUI software 4.0 was applied to process the MR data and quantify the subtracted spectrum in the time domain. The vitro experiment was conducted as a standard to calculate the absolute concentration of GABA. The results indicated the feasibility of MEGA-PRESS sequence operating using 1.5 T scanners.