Intravenous arachnoid granulation volume changes in patients with Parkinson disease

Abstract

We apply novel deep learning algorithms to T2-weighted MRI to test hypotheses regarding arachnoid granulation (AG) hypertrophy in patients with Parkinson’s disease (PD). Using this method, we identify AG protruding into the superior sagittal sinus, which may serve as a site of CSF egress. Results from statistical analyses suggest a significant increase in total AG volume in patients with PD compared to age-matched healthy controls, potentially indicating reduced neurofluid clearance efficiency. Further correlational analyses revealed revealed significant relationships between total AG volume and MiniBEST, as well as significant relationships for AG number with MiniBEST and SDMT. Actigraphy data indicate a negative relationship between total AG volume and sleep efficiency and a positive relationship between AG volume and number of awakenings, but no significant relationships with other actigraphy sleep measures. Finally, sleep efficiency was strongly negatively correlated with AG number before correcting for false discovery rate. Chronic sleep disturbance may contribute to AG hypertrophy as a compensatory mechanism for a dysregulated glymphatic system in patients with PD to clear waste.