Normal Brain Maturation during Childhood: Developmental Trends Characterized with Diffusion-Tensor MR Imaging

Abstract

PURPOSE: To characterize the maturational changes in water diffusion within central gray matter nuclei and central white matter pathways of the human brain by using diffusion-tensor magnetic resonance (MR) imaging. MATERIALS AND METHODS: Retrospective analysis of normal MR examination findings in 153 subjects (age range, 1 day to 11 years) referred for clinical neuroimaging was performed. All studies included diffusion tensor-encoded echo-planar MR imaging. Isotropic diffusion coefficient (D̄) and diffusion anisotropy (Aσ) were measured in the corpus callosum, internal capsule, caudate nucleus, lentiform nucleus, and thalamus. RESULTS: D̄ exhibited biexponential decay with age in gray and white matter regions, except for monoexponential decay in the genu of the corpus callosum. There was a steep nonlinear increase of Aσ in white matter tracts that paralleled the time course of the decline in D̄. In basal ganglia, only a small linear increase in Aσ was observed in patients. Aσ changes in the thalamus were ...