PET Scanning in Parkinson s Disease

This is an in vivo positron emission tomography (PET) study of regional cerebral dopamine and blood flow in normal volunteers, persons with Parkinson s disease (both familial and sporadic), and those with schizophrenia spectrum disorders. The latter also sign consent for NIH approved protocol 89-M-0160, "Inpatient Evaluation of Neuropsychiatric Patients," PI: Daniel Eisenberg, M.D. Using PET with 6-\[F-18\] Fluoro-L-dopa (FDOPA) and (15)0-H2O in a single scan session, both presynaptic dopaminergic function and regional cerebral blood flow (rCBF) are assessed. The kinetic rate constant (Ki) for presynaptic dopaminergic uptake in striatum and other regions is calculated. We compare Ki across subject groups and relate the findings to rCBF. Findings are also related to allelic variation in genes of interest, for determination of which participants sign separate consent for NIH approved protocol 95-M-0150 Neurobiological Investigation of Patients with Schizophrenia Spectrum Disorders and Their Siblings, PI: Karen F. Berman, MD. We also draw comparisons between subjects with inherited vs. sporadic Parkinson s disease to determine whether the PET phenotype is the same in both groups, and we compare system-level, circuit-based pathophysiology across PD and schizophrenia groups. Each subject is further screened with an MRI to rule out structural abnormalities and also to further delineate areas of interest in the PET scans.