Related Experiment Video
Updated: May 7, 2026
12:21
Probing the Brain in Autism Using fMRI and Diffusion Tensor Imaging
Published on: September 12, 2011
Analysis of corpus callosum diffusion tensor imaging parameters in infants
J M Provenzale1, J Isaacson, S Stinnett
1Department of Radiology, Duke University and Emory University; Durham, NC, USA - prove001@mc.duke.edu.
The Neuroradiology Journal
|September 14, 2013
Summary
Radial diffusivity, a key indicator of myelination, decreases significantly more than axial diffusivity or fractional anisotropy increases in infants. This highlights radial diffusivity
Area of Science:
- Neuroimaging
- Developmental Neuroscience
- Biomedical Engineering
Background:
- Fractional anisotropy (FA) is a common diffusion tensor imaging (DTI) metric for white matter development.
- Radial diffusivity may offer a more direct measure of myelination compared to FA.
Purpose of the Study:
- To compare the rate of radial diffusivity decrease with fractional anisotropy (FA) increase and axial diffusivity decrease in the infant corpus callosum during the first year of life.
Main Methods:
- Fifty-three normal infants (0-52 weeks) underwent six-direction DTI scans.
- Regions of interest were placed on the genu and splenium of the corpus callosum.
- Mean and median values for FA, radial diffusivity, axial diffusivity, and ADC were calculated and percent change over the first year was measured.
Main Results:
- Radial diffusivity decreased by 36% in the genu and 53% in the splenium.
- Fractional anisotropy (FA) increased by 25% (genu) and 43% (splenium).
- Decreases in radial diffusivity were 2-3 times greater than axial diffusivity decreases and exceeded FA increases.
Conclusions:
- The rapid decrease in radial diffusivity supports its role in reflecting myelination during early development.
- Radial diffusivity and FA changes represent distinct microstructural alterations in developing white matter.
