Roles of molecular neuroimaging techniques in Parkinsonism

Parkinson's disease affects millions worldwide and is characterized by alpha-synuclein accumulation and loss of dopaminergic neurons in the brain. Until now, there is no cure for Parkinson's disease, and the existing treatments aim to alleviate symptoms. Parkinson's disease diagnosis is primarily based on clinical observation of bradykinesia, mood, and cognition symptoms. Nonetheless, clinical diagnosis has its drawbacks since symptoms of parkinson's disease only manifest in later stages and can be similar to those of other conditions, such as essential tremors or atypical Parkinsonian syndromes. Molecular imaging techniques, including magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT), and positron emission tomography (PET), can objectively detect changes in the brain's neurochemical processes and help diagnose and study neurodegenerative diseases. The paper discusses functional imaging objectives, the tracers employed for imaging, and the condition of each target in Parkinson's disease. Functional imaging can bestow invaluable revelations concerning the intricate mechanisms underlying both motor and nonmotor impairments in Parkinson's disease while concurrently illuminating the involvement of striatal dopamine in behavioral phenomena extending beyond mere motor regulation. Furthermore, this cutting-edge technology exhibits great potential in investigating the preclinical stage of the ailment, thereby enhancing our comprehension of the merits and limitations associated with surgical interventions and the efficacy of neuroprotective approaches.