High spatial resolution MRI and proton MRS of human frontal cortex.

High-resolution MR imaging (312 microns in plane resolution) and MR spectroscopy (0.36 cm3 nominal voxel) have been performed on human frontal cortex using a 3 in surface coil. Localized proton spectra have been obtained from contiguous 6 x 6 x 10 mm voxels using one-dimensional phase encoding, TR 2000 ms and TE 31 ms. Seven healthy subjects were studied using this approach. The spectra from frontal gray matter showed a reproducible pattern characterized by a choline to creatine and N-acetylaspartate to creatine ratio significantly lower than those from cortical white matter. These metabolite ratio differences reflect the lower choline and higher creatine content in gray matter. These preliminary results show the potential of this high spatial-resolution approach for studying brain cortex.