High spatial resolution H-1-MRSI and segmented MRI of cortical gray matterand subcortical white matter in three regions of the human brain

High-resolution MR imaging and spectroscopic imaging were used to study dif ferences in proton spectra between cortical gray matter and subcortical whi te matter in 23 normal volunteers using a 1.5 T scanner and surface coil re ceivers. A point-resolved spectroscopy (PRESS) volume with an 8 x 8 x 8 pha se-encoding matrix was used to acquire over 1900 0.09-0.2 cc spectral voxel s. The high-resolution (0.7 x 0.7 x 0.8 mm(3) or 0.8 x 0.8 x 1 mm(3)) image s were corrected for the surface coil reception profile and segmented into cerebrospinal fluid (CSF) and gray and white matter to correlate with the s pectra, The data showed that N-acetyl aspartate (NAA) and creatine (Cr) wer e higher in the gray matter than in the white matter (NAA(g/w) = 1.4 +/- 0. 36, Cr-g/w = 1.4 +/- 0.41), Choline was significantly lower in the gray mat ter of the occipital lobe than in the white matter (0.73 +/- 0.19), but not significantly different in the other regions, NAA/Cho was found to be sign ificantly higher in the occipital lobe than in the left frontal or vertex r egions. Magn Reson Med 41:21-29, 1999, (C) 1999 Wiley-Liss, Inc.