In the auxiliary examinations for Parkinson's disease, routine laboratory tests as well as CT and MRI scans of the head generally show no specific changes. However, in molecular imaging, PET CT can reveal a significant decrease in striatal dopamine transporter. For olfactory tests, over 80% of Parkinson's patients exhibit olfactory dysfunction. Doppler ultrasound can also detect a significant enhancement of the substantia nigra signal. Despite these advancements in auxiliary examinations, diagnosis in patients with Parkinson's disease still primarily relies on clinical evaluation. According to the 2015 criteria, the diagnostic standards are still based on clinical diagnosis, which includes two main points: first, bradykinesia, where voluntary movements are slow and the speed and amplitude of repetitive movements progressively decrease; second, at least one of the following two manifestations must be present: muscular rigidity or resting tremor.