%0 Generic
%A G., Aghakhanyan
%A A., Vergallo
%A M., Gennaro
%A S., Mazzarri
%A F., Guidoccio
%A C., Radicchi
%A R., Ceravolo
%A G., Tognoni
%A U., Bonuccelli
%A D., Volterrani
%D 2019
%T Supplementary Material for: The Precuneus – A Witness for Excessive Aβ Gathering in Alzheimer’s Disease Pathology
%U https://karger.figshare.com/articles/dataset/Supplementary_Material_for_The_Precuneus_A_Witness_for_Excessive_A_Gathering_in_Alzheimer_s_Disease_Pathology/7775927
%R 10.6084/m9.figshare.7775927.v1
%2 https://karger.figshare.com/ndownloader/files/14478494
%K Alzheimer’s disease
%K Amyloid deposits
%K Beta-amyloid protein
%K Mild cognitive impairment
%K Positron emission tomography scan
%K Precuneus
%K Standardized uptake value ratio
%X Evidence of cortical beta-amyloid (Aβ) load, assessed by Aβ positron emission tomography (Aβ-PET), is an established in vivo biomarker of Alzheimer’s disease (AD)-related pathophysiology. Qualitative assessment of Aβ-PET provides binary information; meanwhile semiquantitative approaches require a parcellation of PET image either manually or by placement of atlas-based volumes of interest. We supposed that a whole-brain approach with voxel-by-voxel standardized uptake value ratio (SUVr) parametric images may better elucidate the spatial trajectories of Aβ burden along the continuum of AD. Methods: We recruited 32 subjects with a diagnosis of probable AD dementia (ADD, n = 20) and mild cognitive impairment due to AD (MCI-AD, n = 12) according to the NIA-AA 2011 criteria. We also enrolled a control group of 6 cognitively healthy individuals (HCs) with preserved cognitive functions and negative Aβ-PET scan. The PET images were spatially normalized using the AV45 PET template in the MNI brain space. Subsequently, parametric SUVr images were calculated using the whole cerebellum as a reference region. A voxel-wise analysis of covariance was used to compare (between groups) the Αβ distribution pattern considering age as a nuisance covariate. Results: Both ADD and MCI-AD subjects showed a widespread increase in radiotracer uptake when compared with HC participants (p < 0.001, uncorrected). After applying a multiple comparison correction (p < 0.05, corrected), a relative large cluster of increased [18F]-florbetapir uptake was observed in the precuneus in the ADD and MCI-AD groups compared to HCs. Voxel-wise regression analysis showed a significant positive linear association between the voxel-wise SUVr values and the disease duration. Conclusions: The voxel-wise semiquantitative analysis shows that the precuneus is a region with higher vulnerability to Aβ depositions when compared to other cortical regions in both MCI-AD and ADD subjects. We think that the precuneus is a promising PET-based outcome measure for clinical trials of drugs targeting brain Aβ. We found a positive association between the overall Aβ-PET SUVr and the disease duration suggesting that the region-specific slow saturation of Aβ deposition continuously takes place as the disease progresses.
%I Karger Publishers