title: Regional apparent metabolite concentrations in young adult brain measured by (1)H MR spectroscopy at 3 Tesla.
abstract: OBJECTIVE
  To quantify and examine the distribution of brain metabolites in normal young adults using single voxel MR spectroscopy at 3 Tesla (T).
  
  
  METHODS
  Short-echo time single-voxel PRESS technique was used to measure the apparent concentration of five metabolites at nine locations in the brains of young adults. Concentrations were estimated by means of an automated fitting method (LCModel) with reference to an unsuppressed water signal and were corrected for T(1) relaxation, T(2) relaxation, and cerebrospinal fluid partial volume. Analysis of variance with Tukey post hoc test was used to evaluate regional variations.
  
  
  RESULTS
  Statistically significant differences in regional concentrations were detected for each of the metabolites. The number of significant differences was greatest for total choline, whereas myo-inositol and the sum of glutamine and glutamate had the fewest. Magnitude of variation was greatest for total choline and least for the sum of N-acetyl aspartate and N-acetylaspartylglutamate.
  
  
  CONCLUSIONS
  In agreement with previous studies at other field strengths, we found heterogeneous distribution of the major spectroscopically measurable brain metabolites. Although the most distinct differences are between tissue types, there is appreciable variation within a tissue type at different locations. The spectra and metabolite concentrations presented should provide a useful reference for both clinical and research MR spectroscopy studies performed at 3T.
authors.affiliation: Diagnostic Radiology Department, Clinical Center, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Eva H
authors.initials: EH
authors.lastname: Baker
authors.forename: Gianpaolo
authors.initials: G
authors.lastname: Basso
authors.forename: Peter B
authors.initials: PB
authors.lastname: Barker
authors.forename: Mari A
authors.initials: MA
authors.lastname: Smith
authors.forename: David
authors.initials: D
authors.lastname: Bonekamp
authors.forename: Alena
authors.initials: A
authors.lastname: Horská
mesh_terms: D000328:Adult; D000367:Age Factors; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000032:analysis; D001923:Brain Chemistry; D002794:Choline / Q000032:analysis; D004151:Dipeptides / Q000032:analysis; D005260:Female; D018698:Glutamic Acid / Q000032:analysis; D005973:Glutamine / Q000032:analysis; D006801:Humans; D007294:Inositol / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male
chemical_list: D004151:Dipeptides; D005973:Glutamine; C027172:isospaglumic acid; D001224:Aspartic Acid; D018698:Glutamic Acid; D007294:Inositol; C000179:N-acetylaspartate; D002794:Choline