Open AccessHippocampal subfield imaging and fractional anisotropy show parallel changes in Alzheimer's disease tau progression using simultaneous tau‐PET/MRI at 3T
Author(s) -
Carlson Mackenzie L.,
Toueg Tyler N.,
Khalighi M. Mehdi,
Castillo Jessa,
Shen Bin,
Azevedo Emily C.,
DiGiacomo Phillip,
Mouchawar Nicole,
Chau Gustavo,
Zaharchuk Greg,
James Michelle L.,
Mormino Elizabeth C.,
Zeineh Michael M.
Publication year - 2021
Publication title -
alzheimer's and dementia: diagnosis, assessment and disease monitoring
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.497
H-Index - 37
ISSN - 2352-8729
DOI - 10.1002/dad2.12218
Subject(s) - perirhinal cortex , subiculum , fractional anisotropy , parahippocampal gyrus , entorhinal cortex , hippocampal formation , neuroscience , hippocampus , diffusion mri , dentate gyrus , tauopathy , magnetic resonance imaging , white matter , temporal lobe , alzheimer's disease , positron emission tomography , psychology , nuclear magnetic resonance , chemistry , pathology , medicine , physics , disease , neurodegeneration , radiology , epilepsy
Alzheimer's disease (AD) is the most common form of dementia, characterized primarily by abnormal aggregation of two proteins, tau and amyloid beta. We assessed tau pathology and white matter connectivity changes in subfields of the hippocampus simultaneously in vivo in AD. Methods Twenty‐four subjects were scanned using simultaneous time‐of‐flight 18 F‐PI‐2620 tau positron emission tomography/3‐Tesla magnetic resonance imaging and automated segmentation. Results We observed extensive tau elevation in the entorhinal/perirhinal regions, intermediate tau elevation in cornu ammonis 1/subiculum, and an absence of tau elevation in the dentate gyrus, relative to controls. Diffusion tensor imaging showed parahippocampal gyral fractional anisotropy was lower in AD and mild cognitive impairment compared to controls and strongly correlated with early tau accumulation in the entorhinal and perirhinal cortices. Discussion This study demonstrates the potential for quantifiable patterns of 18 F‐PI2620 binding in hippocampus subfields, accompanied by diffusion and volume metrics, to be valuable markers of AD.