title: Diffusion tensor spectroscopic imaging of the human brain in children and adults.
abstract: We developed diffusion tensor spectroscopic imaging (DTSI), based on proton-echo-planar-spectroscopic imaging (PEPSI), and evaluated the feasibility of mapping brain metabolite diffusion in adults and children.
  
  
  
  PRESS prelocalized DTSI at 3 Tesla (T) was performed using navigator-based correction of movement-related phase errors and cardiac gating with compensation for repetition time (TR) related variability in T1saturation. Mean diffusivity (MD) and fractional anisotropy (FA) of total N-acetyl-aspartate (tNAA), total creatine (tCr), and total choline (tCho) were measured in eight adults (17-60 years) and 10 children (3-24 months) using bmax= 1734 s/mm2, 1 cc and 4.5 cc voxel sizes, with nominal scan times of 17 min and 8:24 min. Residual movement-related phase encoding ghosting (PEG) was used as a regressor across scans to correct overestimation of MD.
  
  
  
  After correction for PEG, metabolite slice-averaged MD estimated at 20% PEG were lower (P < 0.042) for adults (0.17/0.20/0.18 × 10-3mm2/s) than for children (0.26/0.27/0.24 × 10-3mm2/s). Extrapolated to 0% PEG, the MD estimates decreased further (0.09/0.11/0.11 × 10-3mm2/s versus 0.15/0.16/0.15 × 10-3mm2/s). Slice-averaged FA of tNAA (P = 0.049), tCr (P = 0.067), and tCho (P = 0.003) were higher in children.
  
  
  
  This high-speed DTSI approach with PEG regression allows for estimation of metabolite MD and FA with improved tolerance to movement. Our preliminary data suggesting age-related changes support DTSI as a sensitive technique for investigating intracellular markers of biological processes. Magn Reson Med 78:1246-1256, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
authors: Department of Neurology, University of New Mexico, Albuquerque, New Mexico, USA.|Department of Biomedical Engineering, University of New Mexico, Albuquerque, New Mexico, USA.
authors: Kevin
authors: K
authors: Fotso
authors: Department of Radiology, University of Washington, Seattle, Washington, USA.
authors: Stephen R
authors: SR
authors: Dager
authors: Department of Neurology, University of New Mexico, Albuquerque, New Mexico, USA.|Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico, USA.
authors: Alec
authors: A
authors: Landow
authors: Department of Neurology, University of New Mexico, Albuquerque, New Mexico, USA.
authors: Elena
authors: E
authors: Ackley
authors: Department of Internal Medicine, University of New Mexico, Albuquerque, New Mexico, USA.
authors: Orrin
authors: O
authors: Myers
authors: Seattle Children's Hospital, Seattle, Washington, USA.
authors: Mindy
authors: M
authors: Dixon
authors: Department of Radiology, University of Washington, Seattle, Washington, USA.|Seattle Children's Hospital, Seattle, Washington, USA.
authors: Dennis
authors: D
authors: Shaw
authors: Department of Radiology, University of Washington, Seattle, Washington, USA.
authors: Neva M
authors: NM
authors: Corrigan
authors: Department of Neurology, University of New Mexico, Albuquerque, New Mexico, USA.|Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico, USA.|Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, New Mexico, USA.
authors: Stefan
authors: S
authors: Posse
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging*; D002675:Child, Preschool; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D055815:Young Adult
keywords: age dependence; diffusion tensor; human brain; magnetic resonance spectroscopic imaging; magnetic resonance spectroscopy