Which SPM method should be used to extract hippocampal measures in early Alzheimer's disease?

BACKGROUND AND PURPOSE

To provide guidance regarding the most appropriate voxel-based morphometry (VBM)-derived method for assessing hippocampal atrophy in early Alzheimer's disease (AD).

METHODS

T1-MRI volume data were collected in 23 patients with amnestic mild cognitive impairment (aMCI) and 18 controls. Three types of data (unmodulated and 2 types of modulated MRI) and 2 extraction methods (with reference to the hippocampal peak of atrophy identified from a preliminary whole-brain analysis, or using a template region of interest-ROI-approach) were compared to the gold-standard individual ROI (ROI-i) method through 2 statistical approaches (ANOVA and Pearson's R).

RESULTS

First, whole-brain analyses performed on modulated data are as sensitive as the ROI-i approach in detecting aMCI patients' hippocampal atrophy. Second, values extracted from the ROI-template applied to modulated data provide measures of hippocampal volume comparable to those obtained using the ROI-i approach.

CONCLUSIONS

This study provides guidance on how to extract accurate hippocampal measures from VBM-derived data in early AD, as a time-saving and easy alternative to the reference ROI-i method.