Changes in brain water diffusion during childhood

We studied the changes in brain water diffusion in childhood as seen on dif fusion-weighted MRI in 30 children from 1 day of life to 17 years to provid e a data base and to investigate the correlation of diffusion changes with known patterns of white matter maturation. The apparent diffusion coefficie nt (ADC) and apparent anisotropy (AA) were calculated in numerous regions o f the brain to include major white matter tracts and gray matter. ADC and A A values were directly related to the structural maturity and compactness o f the white matter tracts and changed with aging in a way that predated ear ly myelination markers such as signal change on T1- or T2-weighted images. Diffusion of water is sensitive to structural changes in the brain such as white matter maturation and may be useful in investigating white matter dis orders.