title: Assessing White Matter Microstructure in Brain Regions with Different Myelin Architecture Using MRI.
abstract: OBJECTIVE
  We investigate how known differences in myelin architecture between regions along the cortico-spinal tract and frontal white matter (WM) in 19 healthy adolescents are reflected in several quantitative MRI parameters that have been proposed to non-invasively probe WM microstructure. In a clinically feasible scan time, both conventional imaging sequences as well as microstructural MRI parameters were assessed in order to quantitatively characterise WM regions that are known to differ in the thickness of their myelin sheaths, and in the presence of crossing or parallel fibre organisation.
  
  
  RESULTS
  We found that diffusion imaging, MR spectroscopy (MRS), myelin water fraction (MWF), Magnetization Transfer Imaging, and Quantitative Susceptibility Mapping were myelin-sensitive in different ways, giving complementary information for characterising WM microstructure with different underlying fibre architecture. From the diffusion parameters, neurite density (NODDI) was found to be more sensitive than fractional anisotropy (FA), underlining the limitation of FA in WM crossing fibre regions. In terms of sensitivity to different myelin content, we found that MWF, the mean diffusivity and chemical-shift imaging based MRS yielded the best discrimination between areas.
  
  
  CONCLUSIONS
  Multimodal assessment of WM microstructure was possible within clinically feasible scan times using a broad combination of quantitative microstructural MRI sequences. By assessing new microstructural WM parameters we were able to provide normative data and discuss their interpretation in regions with different myelin architecture, as well as their possible application as biomarker for WM disorders.
authors.affiliation: University Children's Hospital Tübingen, Germany.
authors.forename: Samuel
authors.initials: S
authors.lastname: Groeschel
authors.affiliation: High Field Magnetic Resonance, Max-Planck Institute for Biological Cybernetics, Tübingen, Germany.|Biomedical Magnetic Resonance, University Hospital Tübingen, Germany.
authors.forename: Gisela E
authors.initials: GE
authors.lastname: Hagberg
authors.affiliation: Institute of Computer Science, University of Bonn, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schultz
authors.affiliation: Department Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.
authors.forename: Dávid Z
authors.initials: DZ
authors.lastname: Balla
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Hospital, Tübingen, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Klose
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Hospital, Tübingen, Germany.
authors.forename: Till-Karsten
authors.initials: TK
authors.lastname: Hauser
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Hospital, Tübingen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Nägele
authors.affiliation: Radiological Physics, University of Basel, Basel, Switzerland.
authors.forename: Oliver
authors.initials: O
authors.lastname: Bieri
authors.affiliation: University of British Columbia, Vancouver, Canada.
authors.forename: Thomas
authors.initials: T
authors.lastname: Prasloski
authors.affiliation: University of British Columbia, Vancouver, Canada.
authors.forename: Alex L
authors.initials: AL
authors.lastname: MacKay
authors.affiliation: University Children's Hospital Tübingen, Germany.
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Krägeloh-Mann
authors.affiliation: High Field Magnetic Resonance, Max-Planck Institute for Biological Cybernetics, Tübingen, Germany.|Biomedical Magnetic Resonance, University Hospital Tübingen, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Scheffler
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D001931:Brain Mapping; D002648:Child; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009186:Myelin Sheath / Q000737:chemistry* / Q000378:metabolism; D066127:White Matter / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D055815:Young Adult