Patterns of cerebellar cortex hypermetabolism on motor and cognitive functions in PD.

Previous studies suggest the cerebellum may play a role in both motor and non-motor symptoms of Parkinson's disease (PD), though molecular evidence remains insufficient. We enrolled 104 PD patients to analyze the correlation between cerebellar glucose metabolism and motor and cognitive functions. Metabolic differences across motor subtypes and cognitive stages were examined, along with their relationship to supratentorial structures. Results showed that glucose metabolism in left cerebellar lobules IV and V was negatively correlated with motor function, with no significant differences between tremor-dominant (TD) and postural instability gait difficulty (PIGD) groups. Metabolism in lobules VI, VIII, and the dentate nucleus negatively correlated with cognitive function, with significant differences across cognitive stages. Cerebellar metabolism was closely linked to the cerebral cortex, and a correlation with the thalamus was observed in the TD group. These findings suggest cerebellar glucose metabolism may reflect compensatory mechanisms, highlighting the cerebellum as a potential therapeutic target.