RecruitingEarly Phase 1Drug trialEvaluation of [¹⁸F]MODAG-009 PET Imaging in SynucleinopathiesThis is a single-center, open-label clinical study designed to evaluate the imaging characteristics and safety of \[¹⁸F\]MODAG-009 in participants with Parkinson's disease (PD), Multiple system atrophy (MSA), and Healthy controls (HC). Approximately 13 participants will be enrolled in this study. Each participant will receive a single intravenous injection of \[¹⁸F\]MODAG-009, followed by PET imaging using the investigational United Imaging NeuroEXPLORER (NX) camera.