Abstract
Imaging dopaminergic function with positron emission tomography (PET) and single photon emission computed tomography (SPECT) helps to confirm the presence of parkinsonian disorders and provides a biomarker for monitoring the efficacy of novel neuroprotective and restorative agents. PET and SPECT can reveal how brain dopamine levels are influenced by therapies and also detect loss of serotonergic and cholinergic function. Parkinson‘s disease is associated with microglial activation, and PET can potentially determine whether this is influenced by anti-inflammatory approaches. Finally, PET can prove whether novel therapeutics reach their intended targets and generate dose–brain receptor occupancy profiles.