[18F] - FD17 PET Imaging of α-synuclein: A Clinical Study in α-synucleinopathy Patients

Inclusion Criteria: * 1: Normal cognitive function, CDR score=0（for healthy subjects） 2: Without neurological disorders, major chronic diseases, malignant tumors, or acute infectious diseases (for healthy subjects） 3: Without the family history of neurological disorders related to motor or cognitive impairments(for healthy subjects） 4: Clinical diagnosis of idiopathic PD (for PD patients) 5: Clinical diagnosis of MSA (for MSA patients) 6: Clinical diagnosis of idiopathic RBD (for RBD patients) 7: An informed consent form signed in writing by the subject or their legal guardian or caregiver. 8: Must be abled to be accompanied by nursing staff 9: Must be able to understand and sign a informed consent form before any evaluation and examination 10: Must have medical records to prove that they have undergone surgical sterilization (such as hysterectomy, bilateral oophorectomy, or tubal ligation) or menopause for more than one year.(for female subjects) 11: Must adopt isolation contraception measures within 3 months after the start of this study.(for female subjects) 12: Willing and capable to cooperate with all projects of this study. Exclusion Criteria: * 1: Other severe neurological disorders. Gastrointestinal, cardiovascular, liver, kidney, hematological, tumor, endocrine, respiratory, immunodeficiency, and other serious diseases. 2: Received ionizing radiation outside the scope of this experiment, resulting in an annual radiation exposure dose exceeding 50 mSv in the past year, 3: History of drug abuse or alcoholism 4: Pregnant or lactating women 5: Poor venous conditions, unable to tolerate repeated venipuncture 6: Received experimental drug or device treatment with unclear efficacy or safety in last 1 month. 7: Any situation that the investigators believe may cause harm or potential harm in any aspect related to this study