Fixel based analysis to investigate white matter alterations in individuals with Mild cognitive impairment and Alzheimer’s disease

We investigated fibre tract-specific changes in the whole-brain white matter in individuals with Mild Cognitive Impairment (MCI) and Alzheimer’s Disease (AD) using Fixel Based Analysis (FBA). The results show significant reduction in microstructural fibre bundles in AD, in regions including splenium of the corpus callosum, fornix, and the uncinate fasciculus. FBA-derived measures, including fibre density (FD), and combination of fibre density and cross-section (FDC) demonstrated sensitivity in detecting microstructural white matter alterations in AD. These findings highlight the utility of FBA as a potential biological marker for providing valuable insights into pathophysiologic changes in AD.