Imaging Inflammation in Patients With Parkinson's Disease Dementia or Dementia With Lewy Bodies

This study uses a special type of scan called a positron emission tomography (PET) scan to take pictures of the brain. During the PET scan, a special dye called 11C-PBR28 is injected into the body. 11C-PBR28 sticks to parts of the brain where there is inflammation. The purpose of this study is to see if 11C-PBR28 can detect inflammation in patients with Parkinson's disease dementia or dementia with Lewy bodies. 11C-PBR28 is considered a drug by the Food and Drug Administration. 11C-PBR28 is not a treatment for any disease. Rather, 11C-PBR28 can be used to measure inflammation in the brain.