Open AccessSubcortical amyloid load is associated with shape and volume in cognitively normal individuals
Author(s) -
Rahayel Shady,
Bocti Christian,
Sévigny Dupont Pénélope,
Joannette Maude,
Lavallée Marie Maxime,
Nikelski Jim,
Chertkow Howard,
Joubert Sven
Publication year - 2019
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.24680
Subject(s) - putamen , psychology , hippocampus , neuroscience , pittsburgh compound b , subiculum , hippocampal formation , thalamus , brain morphometry , neuroimaging , magnetic resonance imaging , caudate nucleus , temporal lobe , brain size , cognition , medicine , cognitive impairment , radiology , dentate gyrus , epilepsy
Amyloid‐beta (Aβ) deposition is one of the main hallmarks of Alzheimer's disease. The study assessed the associations between cortical and subcortical 11 C‐Pittsburgh Compound B (PiB) retention, namely, in the hippocampus, amygdala, putamen, caudate, pallidum, and thalamus, and subcortical morphology in cognitively normal individuals. We recruited 104 cognitive normal individuals who underwent extensive neuropsychological assessment, PiB–positron emission tomography (PET) scan, and 3‐T magnetic resonance imaging (MRI) acquisition of T1‐weighted images. Global, cortical, and subcortical regional PiB retention values were derived from each scan and subcortical morphology analyses were performed to investigate vertex‐wise local surface and global volumes, including the hippocampal subfields volumes. We found that subcortical regional Aβ was associated with the surface of the hippocampus, thalamus, and pallidum, with changes being due to volume and shape. Hippocampal Aβ was marginally associated with volume of the whole hippocampus as well as with the CA1 subfield, subiculum, and molecular layer. Participants showing higher subcortical Aβ also showed worse cognitive performance and smaller hippocampal volumes. In contrast, global and cortical PiB uptake did not associate with any subcortical metrics. This study shows that subcortical Aβ is associated with subcortical surface morphology in cognitively normal individuals. This study highlights the importance of quantifying subcortical regional PiB retention values in these individuals.