Dopaminergic function and dopamine transporter binding assessed with positron emission tomography in Parkinson disease.

Background: Measuring progression of Parkinson disease (PD) using positron emission tomography may help demonstrate the efficacy of neuroprotective treatments. To date, (18)F-dopa has been the gold standard to measure presynaptic dopaminergic function in PD, but this tracer might overestimate the rate of neuronal death in PD because its uptake also depends on dopamine turnover rather than exclusively on the density of dopaminergic terminals in the striatum. The latter might be assessed using newly developed ligands of the membrane dopamine transporter.