Fractional anisotropy in white matter tracts of very-low-birth-weight infants

Pediatr Radiol. 2007 Dec;37(12):1216-23. doi: 10.1007/s00247-007-0626-7. Epub 2007 Oct 2.


Background: Advances in neonatal intensive care have not yet reduced the high incidence of neurodevelopmental disability among very-low-birth-weight (VLBW) infants. As neurological deficits are related to white-matter injury, early detection is important. Diffusion tensor imaging (DTI) could be an excellent tool for assessment of white-matter injury.

Objective: To provide DTI fractional anisotropy (FA) reference values for white-matter tracts of VLBW infants for clinical use.

Materials and methods: We retrospectively analysed DTI images of 28 VLBW infants (26-32 weeks gestational age) without evidence of white-matter abnormalities on conventional MRI sequences, and normal developmental outcome (assessed at age 1-3 years). For DTI an echoplanar sequence with diffusion gradient (b = 1,000 s/mm(2)) applied in 25 non-collinear directions was used. We measured FA and apparent diffusion coefficient (ADC) of different white-matter tracts in the first 4 days of life.

Results: A statistically significant correlation was found between gestational age and FA of the posterior limb of the internal capsule in VLBW infants (r = 0.495, P<0.01).

Conclusion: Values of FA and ADC were measured in white-matter tracts of VLBW infants. FA of the pyramidal tracts measured in the first few days after birth is related to gestational age.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Anisotropy
  • Brain / embryology*
  • Brain Mapping / methods*
  • Diffusion Magnetic Resonance Imaging*
  • Female
  • Gestational Age
  • Humans
  • Infant, Newborn
  • Infant, Premature
  • Infant, Very Low Birth Weight*
  • Male
  • Nerve Fibers, Myelinated / ultrastructure*
  • Reference Values
  • Retrospective Studies