title: Changes of axial and radial diffusivities in cerebral white matter led by normal aging.
abstract: OBJECTIVE
  Purpose of the study is to reveal the changes of directional diffusion in cerebral white matter (WM) by normal aging.
  
  
  METHODS
  Thirty-nine volunteers were recruited to examine the changes in the directional diffusion of cerebral white matter (WM) due to normal aging.
  
  
  RESULTS
  No significant difference between the older and younger group (P>.05) was detected in the axial diffusivity (λ(ll)) of any of the regions of interest (ROI), while radial diffusivity (λ(perpendicular)) was significantly higher in the older group (P<.05) except for occipital lobe WM.
  
  
  CONCLUSIONS
  λ(ll) and λ(perpendicular) may be used as in vivo markers that differentially and specifically reflect the WM changes of normal aging.
authors.affiliation: Department of Radiology, the Second Affiliated Hospital, Chongqing Medical University, Chongqing, PR China.
authors.forename: W-J
authors.initials: WJ
authors.lastname: Zhong
authors.forename: D-J
authors.initials: DJ
authors.lastname: Guo
authors.forename: J-N
authors.initials: JN
authors.lastname: Zhao
authors.forename: W-B
authors.initials: WB
authors.lastname: Xie
authors.forename: W-J
authors.initials: WJ
authors.lastname: Chen
authors.forename: W
authors.initials: W
authors.lastname: Wu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult