title: Whole-brain proton MR spectroscopic imaging in Parkinson's disease.
abstract: OBJECTIVE
  To examine the distributions of proton magnetic resonance spectroscopy (MRS) observed metabolites in Parkinson's disease (PD) throughout the whole brain.
  
  
  METHODS
  Twelve PD patients and 18 age-matched controls were studied using neuropsychological testing, MRI and volumetric MR spectroscopic imaging. Average values of signal normalized metabolite values for N-acetyl-aspartate, total-creatine, and total-choline (NAA, total-Cre, total-Cho, respectively) and their ratios were calculated for gray matter (GM) and white matter (WM) in each lobar brain region.
  
  
  RESULTS
  Analyses revealed altered metabolite values in PD subjects relative to controls within the GM of the temporal lobe (right: elevated Cre, P = .027; decreased NAA/Cre, P = .019; decreased Cho/Cre, P = .001 and left: decreased NAA/Cre; P = .001, decreased Cho/Cre, P = .007); the right occipital lobe (decreased NAA, P = .032 and NAA/Cre, P = .016); and the total cerebrum GM (decreased NAA/Cre, P = .029). No meaningful correlations were obtained between abnormal metabolite values and the neuropsychological measures.
  
  
  CONCLUSIONS
  PD is associated with widespread alterations of brain metabolite concentrations, with a primary finding of increased creatine. Higher creatine values in our PD sample may reflect greater neuronal energy expenditure early in the disease process that is compensatory. This is the first whole brain MRS study of PD that has examined metabolite changes across a large fraction of the brain volume, including the cortical mantle.
authors.affiliation: Department of Neurology, University of Miami Miller School of Medicine, Miami, FL; Department of Psychology, University of Miami, Coral Gables, FL.
authors.forename: Bonnie E
authors.initials: BE
authors.lastname: Levin
authors.forename: Heather L
authors.initials: HL
authors.lastname: Katzen
authors.forename: Andrew
authors.initials: A
authors.lastname: Maudsley
authors.forename: Judith
authors.initials: J
authors.lastname: Post
authors.forename: Connie
authors.initials: C
authors.lastname: Myerson
authors.forename: Varan
authors.initials: V
authors.lastname: Govind
authors.forename: Fatta
authors.initials: F
authors.lastname: Nahab
authors.forename: Blake
authors.initials: B
authors.lastname: Scanlon
authors.forename: Aaron
authors.initials: A
authors.lastname: Mittel
mesh_terms: D000328:Adult; D000368:Aged; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D002794:Choline / Q000378:metabolism*; D003401:Creatine / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D057054:Molecular Imaging / Q000379:methods*; D010300:Parkinson Disease / Q000378:metabolism* / Q000473:pathology*; D066244:Proton Magnetic Resonance Spectroscopy; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014018:Tissue Distribution
chemical_list: D015415:Biomarkers; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline