Diffusion tensor imaging of normal appearing white matter and its correlation with cognitive functioning in mild cognitive impairment and Alzheimer's disease.

Diffusion tensor imaging (DTI) was used to examine the microstructural integrity of normal appearing white matter (NAWM) in subjects with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Significant frontal, temporal, and parietal white matter diffusion tensor changes were demonstrated in MCI and AD compared with normal controls. These changes were correlated with cognitive functioning, and are consistent with a hypothesized loss of axonal processes in affected regions.