Implications of habitat analysis for substantia nigra based on diffusion kurtosis imaging in Parkinson's disease

Motivation: Substantia nigra (SN), a core pathological nucleus of Parkinson's disease (PD), exhibits microstructural heterogeneity that remains poorly characterized. Goal(s): Evaluate the heterogeneity of microstructural changes in the SN using diffusion kurtosis imaging (DKI)-based habitat analysis and assess the diagnostic utility of habitat-derived features in PD. Approach: 113 PD patients and 110 healthy controls with DKI were analyzed. Habitat fractions and their diagnostic performance were assessed using machine learning models. Results: PD patients demonstrated heterogeneous changes in SN microstructure reflected by the difference in the fraction of habitats and the robust diagnostic efficacy. Impact: This study verified habitat analysis based on DKI can subdivide the SN from the aspect of microstructure to further analyze the heterogenetic pathology.