Standard practice in neurology uses imaging, such as magnetic resonance imaging, or MRI, of brain structures to make a diagnosis. But in Parkinson’s disease (PD), additional imaging technologies are needed since MRI is not particularly helpful to make the diagnosis. Recent studies have turned to brain imaging using new technological tools, looking for ways to better assess the disease, predict its progression, and evaluate potential drugs to treat it or slow its progression. Biomarkers  that can be seen in this type of brain imaging can be physical structures or biochemical signals, and researchers believe some correlate with the motor abilities of people with PD. Dr. Jon Stoessl of the University of British Columbia in Canada uses positron emission tomography, or PET scans, to research chemical biomarkers in the brain, such as dopamine, for these purposes.