The impact of amyloid-β and ferritin on ultra-high-field R2* and quantitative susceptibility mapping

Amyloid plaques, an established hallmark of Alzheimer's disease, are often demonstrably associated with iron deposits post-mortem. Previous T2*-weighted and phase information from ultra-high-field MR microscopy and clinical MRI has shown the potential to detect amyloid deposits in vivo and ex vivo. We investigated the relative contributions to contrast from amyloid-β (Aβ) aggregates with and without ferritin-bound iron in vitro, for R2* and quantitative susceptibility maps (QSM) with 86 μm isotropic resolution at 9.4T. We also demonstrated the quantitative signal evolution with the formation of amyloid aggregates, and the correlation of the signals with the Aβ and ferritin content.