Significance of the potential role of pharmacological MRI (phMRI) in diagnosis of Parkinson's disease

The initial diagnosis of Parkinson's disease (PD) is currently based on a clinical assessment. Many patients who receive an initial diagnosis of PD have parkinsonian features related to other diseases such as essential tremor, vascular parkinsonism and atypical parkinsonian disorder. It has been challenging to differentiate PD from those disorders, especially in the early disease stages, due to an overlap of clinical signs and symptoms. Therefore, there is a great need for development of noninvasive, highly sensitive, and widely available imaging methods that can potentially be used to assistant physicians to make more accurate diagnosis of the disease; and to longitudinally monitor treatment of PD. Recent advance of pharmacological MRI (phMRI) technology allows non-invasively mapping functional stages for nigrostriatal dopamine (DA) system. This article aims to review research findings primarily from our group in nonhuman primates modeling the neurodegenerative disease on the value of phMRI techniques in the diagnosis of PD.