Study Rationale:
Substantia nigra pars compacta (SNpc) and locus coeruleus (LC) are key brain areas involved in Parkinson’s disease. The loss of important chemicals (dopamine and norepinephrine) made by cells in these areas leads to many of the symptoms of Parkinson’s disease. Our group develops and uses magnetic resonance imaging (MRI) techniques that can measure changes in these brain areas. By studying SNpc and LC with MRI over time, we will attempt to identify changes that occur as Parkinson’s disease (PD) progresses.
Hypothesis:
Using MRI techniques specially designed to measure changes in SNpc and LC, we can identify and quantify changes that occur in these key areas as PD progresses.
Study Design:
Groups of 40 individuals with and without Parkinson’s disease will have MRI scans and detailed clinical evaluations at baseline and again 16 months later. The MRI scans will include multiple “pulse sequences” or programs that acquire images with different types of information about SNpc and LC. The MRI data will be analyzed to assess for changes over time in SNpc and LC that occur with progression of Parkinson’s disease.
Impact on Diagnosis/Treatment of Parkinson’s Disease:
The outputs of this study, MRI biomarkers of Parkinson’s disease progression, may be developed as tools to more efficiently develop therapies for Parkinson’s disease. MRI measurements of the brain changes caused by PD may be used to determine whether or not a drug can slow progression of the disease process.
Next Steps for Development:
The biomarker candidates identified in this study can be further developed through validation in a larger, multi-site study. Assessment for correlations between MRI biomarkers and molecular biomarkers, such those measured from blood samples, will also be needed to help develop screening approaches for early and asymptomatic Parkinson’s disease.