Postmortem imaging reveals patterns of medial temporal lobe vulnerability to tau pathology in Alzheimer's disease.
Sadhana RavikumarAmanda E DenningSydney LimEunice ChungNiyousha SadeghpourRanjit IttyerahLaura E M WisseSandhitsu R DasLong XieJohn L RobinsonTheresa SchuckEdward B LeeJohn A DetreM Dylan TisdallKarthik PrabhakaranGabor MizseiMaria Mercedes Iñiguez de Onzono MartinMarı'a Del Mar Arroyo JiménezMonica MũnozMaria Del Pilar Marcos RabalSandra Cebada-SánchezJosé Carlos Delgado GonzálezCarlos de la Rosa PrietoDavid J IrwinDavid A WolkRicardo InsaustiPaul A YushkevichPublished in: Nature communications (2024)
Our current understanding of the spread and neurodegenerative effects of tau neurofibrillary tangles (NFTs) within the medial temporal lobe (MTL) during the early stages of Alzheimer's Disease (AD) is limited by the presence of confounding non-AD pathologies and the two-dimensional (2-D) nature of conventional histology studies. Here, we combine ex vivo MRI and serial histological imaging from 25 human MTL specimens to present a detailed, 3-D characterization of quantitative NFT burden measures in the space of a high-resolution, ex vivo atlas with cytoarchitecturally-defined subregion labels, that can be used to inform future in vivo neuroimaging studies. Average maps show a clear anterior to poster gradient in NFT distribution and a precise, spatial pattern with highest levels of NFTs found not just within the transentorhinal region but also the cornu ammonis (CA1) subfield. Additionally, we identify granular MTL regions where measures of neurodegeneration are likely to be linked to NFTs specifically, and thus potentially more sensitive as early AD biomarkers.