MR image segmentation and tissue metabolite contrast in 1H spectroscopic imaging of normal and aging brain.
The impact of image segmentation on 0.84-ml nominal voxel volume proton spectroscopic imaging in normal brain and in age-related cortical atrophy was investigated. Segmentation improved the gray matter-white matter (GM-WM) contrast for N-acetyl aspartate (NAA)/creatine (Cr) and choline (Cho)/Cr in normal brain, and for NAA/Cho and NAA/Cr in atrophic brain. NAA(GM/WM) (approximately 0.7), Cho(GM/WM) (approximately 0.8), and Cr(GM/WM) (approximately 1.3) in normal brain obtained with segmentation agreed with values obtained with quantitative magnetic resonance spectroscopy. Age-related cortical atrophy led to decreased cortical GM NAA/Cho and NAA/Cr; no changes were evident in WM 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.
Lundbom
N
N
Neuroimaging Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA. ninalundbom@huch.fi
Barnett
A
A
Bonavita
S
S
Patronas
N
N
Rajapakse
J
J
Tedeschi
Di Chiro
G
G
D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000473:pathology*; D001224:Aspartic Acid / Q000032:analysis; D001284:Atrophy; D001921:Brain / Q000473:pathology*; D001923:Brain Chemistry; D002794:Choline / Q000032:analysis; D003401:Creatine / Q000032:analysis; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D008297:Male
D001224:Aspartic Acid; D003401:Creatine; D002794:Choline