Longitudinal Diffusion Tensor Imaging of Healthy Brain Development in Children

Catherine Lebel¹, Christian Beaulieu¹

Cross-sectional DTI studies demonstrate fractional anisotropy (FA) increases during childhood and adolescence, but longitudinal DTI studies are lacking. We examined longitudinal brain development in 45 healthy children initially aged 5-12 years. Each had 2-4 MRI scans at 1-6 year intervals. Tractography was used to assess eleven major white matter tracts. The genu and splenium of the corpus callosum, and right inferior fronto-occipital fasciculus showed non-linear FA changes; all other tracts showed linear FA increases. Males had significantly greater FA in several tracts. This study provides insight into white matter maturation during childhood and adolescence, including timing and sex differences.