Media type: E-Article Title: Diffusion tensor spectroscopic imaging of the human brain in children and adults Contributor: Fotso, Kevin; Dager, Stephen R.; Landow, Alec; Ackley, Elena; Myers, Orrin; Dixon, Mindy; Shaw, Dennis; Corrigan, Neva M.; Posse, Stefan imprint: Wiley, 2017 Published in: Magnetic Resonance in Medicine Language: English DOI: 10.1002/mrm.26518 ISSN: 0740-3194; 1522-2594 Keywords: Radiology, Nuclear Medicine and imaging Origination: Footnote: Description: <jats:sec><jats:title>Purpose</jats:title><jats:p>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.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>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 T<jats:sub>1</jats:sub> saturation. 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 b<jats:sub>max</jats:sub> = 1734 s/mm<jats:sup>2</jats:sup>, 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.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>After correction for PEG, metabolite slice‐averaged MD estimated at 20% PEG were lower (<jats:italic>P</jats:italic> < 0.042) for adults (0.17/0.20/0.18 × 10<jats:sup>−3</jats:sup> mm<jats:sup>2</jats:sup>/s) than for children (0.26/0.27/0.24 × 10<jats:sup>−3</jats:sup> mm<jats:sup>2</jats:sup>/s). Extrapolated to 0% PEG, the MD estimates decreased further (0.09/0.11/0.11 × 10<jats:sup>−3</jats:sup> mm<jats:sup>2</jats:sup>/s versus 0.15/0.16/0.15 × 10<jats:sup>−3</jats:sup> mm<jats:sup>2</jats:sup>/s). Slice‐averaged FA of tNAA (<jats:italic>P</jats:italic> = 0.049), tCr (<jats:italic>P</jats:italic> = 0.067), and tCho (<jats:italic>P</jats:italic> = 0.003) were higher in children.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>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.</jats:p></jats:sec>