Axonal abnormalities in deep brain nuclear pathways across multiple neurotransmitter systems in de novo Parkinson’s disease patients

The present study systematically and comprehensively reviewed the axonal pathways projecting from the deep brain nuclei that are emerging targets for treating Parkinson’s disease (PD). We tracked 124 deep brain nuclear pathways across different neurotransmitters systems in the high angular HCP-1065 diffusion MRI template using diffusion MRI tractography. With the trajectories of these pathways, we successfully used Parkinson's Progression Markers Initiative (PPMI) diffusion tensor imaging (DTI) data to characterize abnormal DTI changes in noradrenergic and serotoninergic pathways in relation to the severity of non-motor symptoms in de novo PD patients, suggesting a wide neural involvement of clinical PD manifestations.