Objective: To investigate the association of multi-modality neuroimaging features and cognitive function in mild cognitive impairment (MCI) and Alzheimer's disease (AD).
Methods: Nine individuals with amnestic MCI (aMCI), fifteen patients with mild probable AD, and eleven age-controlled cognitively normal controls (NC) were recruited. All participants were administered with mini-mental status examination (MMSE) and Cognitive assessment screening instrument (CASI) to assess general cognitive function. Optimized voxel-based morphometry (VBM) was used for the analysis with 3-D high resolution anatomical images. Values of fractional anisotropy (FA) and mean apparent diffusivity coefficient (ADC) were measured from different brain regions on diffusion-tensor images (DTI). The relationship between structural atrophy and DTI-based measurements in the selected brain regions was examined.
Results: The scores of MMSE and CASI were correlated with the volumetric changes in such areas as temporal, frontal and parietal lobes, and cingulate gyrus and hippocampal gyrus (P<0.001). The scores of MMSE and CASI were positively correlated with FA values, and negatively with ADC values in the white-matter-affected regions including temporal, frontal, parietal lobes, cingulate gyrus, and parahippocampal gyrus (P<0.05).
Conclusions: Cognitive decline was associated with atrophy and white matter microstructural alterations in temporal, frontal, parietal lobes, cingulate gyrus, and parahippocampal gyrus in MCI and AD. Multi-modality imaging technique may be important in elucidating the brain mechanism of cognitive impairment.