Multimodal assessment of nigrostriatal degeneration in de novo Parkinson’s disease

FDOPA uptake rate, fractional volume of free-water and R2* relaxometry are imaging biomarkers sensitive to dopaminergic decline, microstructural degeneration, and iron disruption respectively, three pathological processes developed within the nigrostriatal system in Parkinson’s disease (PD). A multimodal comprehensive characterization of these biomarkers in early PD was performed, assessing them within striatum and substantia nigra pars compacta in a de novo PD cohort. While iron disruption was not observed, PD subjects revealed dopaminergic and microstructural alterations within the nigrostriatal system, following both similar spatial patterns. These results serve to improve our understanding of nigrostriatal vulnerability and degeneration in early PD.