High Resolution Diffusion Tensor MRI Imaging as a Biomarker of Parkinson's Disease Diagnosis and Disease Progression

Objective/Rationale: 
As Parkinson’s disease (PD) is moving into the era of neuroprotective interventions one of the major objectives is the development of a biomarker of PD diagnosis.  This study will test the utility of high resolution 3 Tesla diffusion tensor imaging (DTI) MRI for the diagnosis of early PD.
Project Description: 
This is a two year project. The study will recruit the following groups of subjects: 15 subjects with newly diagnosed untreated PD, 15 age matched controls and 15 subjects with advanced PD.  All subjects will have a detailed neurological examination and will undergo MRI imaging that will include structural and DTI sequences. MRI results will be compared between the groups to establish the accuracy of DTI MRI as compared to the clinical diagnosis. MRI data also will be compared between subjects with early and advanced PD to establish if there is a relationship between the degree of DTI MRI change and severity of parkinsonism. Subjects with early PD will be rescanned a year later to explore the role of DTI MRI as a biomarker of PD progression. A subset of PD subjects will be scanned on and off medications to establish the impact of dopaminergic therapy on results of DTI MRI imaging. 
Relevance to Diagnosis/Treatment of Parkinson’s Disease:  
If confirmed, high resolution DTI MRI imaging could serve as a widely available and reliable tool for confirmation of an early diagnosis of PD and potentially for screening subjects at risk.
Anticipated Outcome: 
This study will confirm recent data on the utility of high resolution DTI MRI imaging for the early diagnosis of PD as well as examining the role of this imaging modality in monitoring progression of PD and measuring disease severity.