MR image segmentation and tissue metabolite contrast in H-1 spectroscopic imaging of normal and aging brain

The impact of image segmentation on 0.84-ml nominal voxel volume proton spe ctroscopic imaging in normal brain and in age-related cortical atrophy was investigated. Segmentation improved the gray matter-white matter (GM-WM) co ntrast for N-acetyl aspartate (NAA)/creatine (Cr) and choline (Cho)/Cr in n ormal brain, and for NAA/Cho and NAA/Cr in atrophic brain, NAA(GM/WM) (simi lar to 0.7), Cho(GM/WM) (similar to 0.8), and Cr-GM/WM (similar to 1.3) in normal brain obtained with segmentation agreed with values obtained with qu antitative magnetic resonance spectroscopy. Age-related cortical atrophy le d to decreased cortical GM NAA/Cho and NAA/Cr; no changes were evident in W M or in NAA(GM/WM) Cho(GM/WM) or Cr-GM/WM GM/WM metabolite analysis may be of limited use in conditions in which parallel metabolite changes occur in WM and GM. Published 1999 Wiley-Liss, Inc.dagger.