title: T(2) relaxometry of normal pediatric brain development.
abstract: OBJECTIVE
  To establish normal age-related changes in the magnetic resonance (MR) T(2) relaxation time constants of brain using data collected as part of the National Institutes of Health (NIH) MRI Study of Normal Brain Development.
  
  
  METHODS
  This multicenter study of normal brain and behavior development provides both longitudinal and cross-sectional data, and has enabled us to investigate T(2) evolution in several brain regions in healthy children within the age range of birth through 4 years 5 months. Due to the multicenter nature of the study and the extended period of data collection, periodically scanned inanimate and human phantoms were used to assess intra- and intersite variability.
  
  
  RESULTS
  The main finding of this work, based on over 340 scans, is the identification and parameterization of the monoexponential evolution of T(2) from birth through 4 years 5 months of age in various brain structures.
  
  
  CONCLUSIONS
  The exponentially decaying T(2) behavior is believed to reflect the rapid changes in water content as well as myelination during brain development. The data will become publicly available as part of a normative pediatric MRI and clinical/behavioral database, thereby providing a basis for comparison in studies assessing normal brain development, and studies of deviations due to various neurological, neuropsychiatric, and developmental disorders.
authors.affiliation: Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada. ilana@bic.mni.mcgill.ca
authors.forename: Ilana R
authors.initials: IR
authors.lastname: Leppert
authors.forename: C Robert
authors.initials: CR
authors.lastname: Almli
authors.forename: Robert C
authors.initials: RC
authors.lastname: McKinstry
authors.forename: Robert V
authors.initials: RV
authors.lastname: Mulkern
authors.forename: Carlo
authors.initials: C
authors.lastname: Pierpaoli
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Rivkin
authors.forename: G Bruce
authors.initials: GB
authors.lastname: Pike
mesh_terms: D000375:Aging / Q000502:physiology; D001921:Brain / Q000254:growth & development*; D001931:Brain Mapping / Q000379:methods*; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016014:Linear Models; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D019047:Phantoms, Imaging; D015203:Reproducibility of Results