Structural MRI discriminates individuals with Mild Cognitive Impairment from age-matched controls: a combined neuropsychological and voxel based morphometry study.

BACKGROUND: Several previous studies have reported that amnestic mild cognitive impairment (aMCI), a significant risk factor for Alzheimer's disease (AD), is associated with greater atrophy in the medial temporal lobe (MTL) and posterior cingulate gyrus (PCG).
METHOD: In the present study, we examined the cross-sectional accuracy (i.e., the sensitivity and specificity) of voxel-based morphometry (VBM) in discriminating individuals with MCI (n =15) from healthy age-matched controls (n =15). In addition, we also sought to determine whether baseline GM volume predicted aMCI patients that converted to AD from those that did not approximately 2 years after the baseline visit.
RESULTS: MCI patients were found to display significantly less GM volume in several hypothesized regions including the MTL and PCG relative to the age-matched controls (p < 0.01). Logistic regression analysis and receiver operating characteristic (ROC) curves for GM volume in the anterior MTL and PCG revealed high discriminative accuracy of 87%. By contrast, baseline GM volume in anterior MTL and PCG did not appear to be sensitive to changes in clinical status at the follow-up visit.
CONCLUSION: These results suggest that VBM might be useful at characterizing GM volume reductions associated with the diagnosis of aMCI.