In vivo detection of gray and white matter differences in GABA concentration in the human brain

Abstract

A novel selective multiple quantum filtering-based chemical shift imaging method was developed for acquiring GABA images in the human brain at 3 T. This method allows a concomitant acquisition of an interleaved total creatine image with the same spatial resolution. Using T 1-based image segmentation and a nonlinear least square regression analysis of GABA-to-total creatine concentration ratios in frontal and parietal lobes of healthy adult volunteers as a function of the tissue gray matter fraction, the mean GABA concentration in gray and white matter was determined to be 1.30 ± 0.36 μmol/g and 0.16 ± 0.16 μmol/g (mean ± SD, n = 13), respectively. It is expected that this method will become a useful tool for studying GABAergic function in the human brain in vivo.