Published in NeuroImage: Clinical (2025).

Work by Christoffer Olsson, Mikael Skorpil, Per Svenningsson, and Rodrigo Moreno.

Abstract

This study combines two advanced MRI-based techniques to characterise how Parkinson’s disease (PD) affects brain tissue. Magnetic Resonance Elastography (MRE) is a novel technique that measures the mechanical properties of the brain — such as stiffness and viscosity. The study also employs multidimensional diffusion MRI (MD-dMRI) to extract microstructural parameters including microscopic fractional anisotropy (μFA), complementing the mechanical measures with microstructural ones.

Main results. There are significant softening effects in the temporal and occipital lobes due to PD, associated with an increase in the mean diffusivity in those regions, whereas other microstructural properties remain largely unchanged. The mesencephalon does not soften due to PD but shows signs of neuronal atrophy. The authors hypothesise that age effects can mostly explain neuronal atrophy, whereas softening due to PD involves additional mechanisms.