The role of imaging in the diagnosis of vascular parkinsonism.

Parkinsonism is a syndrome that features bradykinesia (slowness of the initiation of voluntary movement) and at least 1 of the following conditions: rest tremor, muscular rigidity, or postural instability. Criteria for the clinical diagnosis of vascular parkinsonism (VP) have been proposed, which are derived from a postmortem examination study. Computed tomography and magnetic resonance imaging can support this clinical diagnosis with positive imaging findings. Dopamine transporter single-photon emission computed tomography may also be of help to distinguish VP from Parkinson disease and other parkinsonisms.