Julio Acosta-Cabronero1,
Dina Kronhaus2, Robert J. Arnold1, Guy B. Williams3,
Peter J. Nestor4
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; 4Plasticity
and Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE),
Magdeburg, Saxony-Anhalt, Germany
This study explored the hypothesis that diffusion tensor imaging (DTI) abnormalities in Alzheimers disease (AD) should capture axonal damage or cell death. This was done by testing the linear dependence of DTI-derived metrics on hippocampal atrophy using whole-brain and region of interest approaches. The results revealed that in the same white matter areas where axial diffusivity (&[lambda]1) is abnormal early, progressive change in radial diffusivity (RD) and fractional anisotropy (FA) but not in &[lambda]1 predict atrophy in the hippocampus. What is then &[lambda]1 sensitive to in very early disease stages?&[prime]