Pet Studies of Movement Disorders

This chapter reviews the current information on the use of Positron emission tomography (PET) and movement disorders. Parkinson’s disease is a degenerative neurological disorder characterized by tremor, rigidity, bradykinesia, and postural instability. Therapy is aimed at replacing the neurochemical defect in this condition. L-dopa, the precursor of dopamine, has been used successfully in the treatment of patients with parkinsonism. Dopamine does not cross the blood brain barrier and cannot be used as a therapeutic agent. Parkinsonism may be present in conditions other than Parkinson’s disease. Disease processes that affect the substantia nigra or caudate nucleus and putamen may present with similar symptoms. Cerebral metabolism studies with fluorodeoxyglucose (FDG) have been performed in patients with unilateral and bilateral parkinsonism. PET may be employed to study the nigrostriatal dopamine pathway during life. PET studies of dopamine receptors in Parkinson’s disease have been very preliminary.