Peter J. Nestor1, Stephanie Alley2, Guy B. Williams3, Dina Kronhaus2, Julio Acosta-Cabronero1
1Department of Clinical Neurosciences, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom; 2Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom; 3Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, Cambridgeshire, United Kingdom
Various, sometimes inconsistent, results have been reported in Alzheimers disease (AD) using DTI. This study explored the hypothesis that this may, in part, relate to different tensor behaviors at different disease stages. Region of interest and whole brain approaches were used to study changes in DTI metrics in (i) two AD cohorts of differing severity and (ii) a cohort that had been scanned longitudinally. The results indicated that axial diffusion became abnormal early but then remained relatively static with advancing disease. Radial diffusion, and therefore fractional anisotropy, were relatively preserved early but became increasingly abnormal with disease progression.