VIRTUAL HISTOLOGY OF BRAIN ATROPHY PROGRESSION IN DE NOVO PARKINSON’S DISEASE
- Christina Tremblay, Canada
Abstract
Aims
The relationship between brain atrophy in Parkinson’s disease (PD) and specific CNS cell type distribution is unclear. This study aims to determine whether specific cell type distributions are related to atrophy progression after two and four years in patients enrolled with de novo PD.
Methods
Deformation-based morphometry (DBM) maps computed from 74 PD patients (50 men) T1-weighted MRI at baseline, two and four years, and 157 healthy control (115 men) at baseline in the PPMI database were used as atrophy maps. Then, W-score maps were computed to regress out the expected effect of age and sex. Atrophy differences between time points were compared with rANOVA and the pTFCE approach (pFWE<.05). To investigate the relationship between regional cell density and atrophy progression, a virtual histology approach with seven cell-class gene expression maps from Seidlitz et al. (2019) were used.
Results
Small clusters of atrophy progression were found after two years in the bilateral temporal gyrus, white matter (WM), left precuneus and right caudate. The progression was more widespread after four years and overlapped with the bilateral WM, temporal, parietal and occipital cortex in addition to the caudate and putamen. Significant correlations were found between the density of endothelial cells and the regional atrophy progression after two (r=-.15, pspin=.04) and four years (r=-.19, pspin=.01). The atrophy progression was also significantly correlated with oligodendrocyte density after two (r=-.11, pspin=.04) and four years (r=-.11, pspin=.049).
Conclusions
The atrophy in brain regions with higher density of endothelial cells or oligodendrocytes progresses more slowly in de novo Parkinson’s disease.