[Characteristics of regional cerebral circulation in parkinsonism patients according the 133Xe clearance findings].

As a rule, in patients with idiopathic parkinsonism the cerebral volume blood flow is decreased in the parietal lobes. Patients with vascular parkinsonism display a decreased blood flow in the frontal and occiptial lobes, more so in the parietal. An inhalation of pure oxygen in the control group of normals decreased the general cerebral blood flow, while in parkinsonic patients it increased it only in the parietal lobes. Treatment with l-dopa regularly and significantly increased the general and regional cerebral blood flow.