title: Age-related changes of normal adult brain structure: analysed with diffusion tensor imaging.
abstract: BACKGROUND
  It is known that the brain structure changes with normal aging. The objective of this study was to quantify the anisotropy and average diffusion coefficient (DCavg) of the brain in normal adults to demonstrate the microstructure changes of brain with aging.
  
  
  METHODS
  One hundred and six normal adults were examined with diffusion tensor imaging (DTI). The fractional anisotropy (FA), 1-volume ratio (1-VR), relative anisotropy (RA) and average diffusion coefficient (DCavg) of different anatomic sites of brain were measured, correlated with age and compared among three broad age groups.
  
  
  RESULTS
  Except in lentiform nucleus, the anisotropy increased and DCavg decreased with aging. Both anisotropy and DCavg of lentiform nucleus increased with aging. The normal reference values of DTI parameters of normal Chinese adult in major anatomic sites were acquired.
  
  
  CONCLUSIONS
  DTI data obtained noninvasively can reflect the microstructural changes with aging. The normal reference values acquired can serve as reference standards in differentiation of brain white matter diseases.
authors.affiliation: Department of Radiology, General Hospital, Tianjin Medical University, Tianjin 300052, China. cjr.zhangyunting@vip.163.com
authors.forename: Yun-ting
authors.initials: YT
authors.lastname: Zhang
authors.forename: Chun-yan
authors.initials: CY
authors.lastname: Zhang
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000473:pathology*; D016880:Anisotropy; D001921:Brain / Q000473:pathology*; D004058:Diffusion; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged