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

High‐resolution MR imaging and spectroscopic imaging were used to study differences in proton spectra between cortical gray matter and subcortical white matter in 23 normal volunteers using a 1.5 T scanner and surface coil receivers. A point‐resolved spectroscopy (PRESS) volume with an 8 × 8 × 8 phase‐encoding matrix was used to acquire over 1900 0.09–0.2 cc spectral voxels. The high‐resolution (0.7 × 0.7 × 0.8 mm3 or 0.8 × 0.8 × 1 mm3) images were corrected for the surface coil reception profile and segmented into cerebrospinal fluid (CSF) and gray and white matter to correlate with the spectra. The data showed that N‐acetyl aspartate (NAA) and creatine (Cr) were higher in the gray matter than in the white matter (NAAg/w = 1.4 ± 0.36, Crg/w = 1.4 ± 0.41). Choline was significantly lower in the gray matter 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 significantly higher in the occipital lobe than in the left frontal or vertex regions. Magn Reson Med 41:21‐29, 1999. © 1999 Wiley‐Liss, Inc.