Positron Emission Tomography and Single-Photon Emission Tomography in the Diagnosis of Parkinson’s Disease Differential Diagnosis From Parkinson-Like Degenerative Diseases

Parkinsonian symptoms are associated with a number of neurodegenerative disorders, such as Parkinson’s disease, multiple system atrophy, and progressive supranuclear palsy. Positron emission tomography (PET) and single-photon emission tomography (SPECT) now are able to visualize and quantify changes in cerebral blood flow, glucose metabolism, and neurotransmitter function produced by parkinsonian disorders. Both PET and SPECT have become important tools in the differential diagnosis of these diseases and may have sufficient sensitivity to detect neuronal changes before the onset of clinical symptoms. Imaging is now being used to elucidate the genetic contribution to Parkinson’s disease and in longitudinal studies to assess the efficacy and mode of action of neuroprotective drug and surgical treatments.