title: Regional blood flow in hemiparkinsonism.
abstract: Positron emission tomography was used to measure global and local blood flow in 11 patients with hemiparkinsonism (before and after an acute oral dose of L-dopa) and in 26 normal subjects. Global hemispheric blood flow was not significantly different between the patients [45 +/- 11 ml/(min X 100 g)] and the controls [49 +/- 8 ml/(min X 100 g)]. After L-dopa, the patients' mean global hemispheric flow did not change. Measurements of local blood flow from specific, anatomically defined cortical and basal ganglia regions were performed using a newly developed stereotactic localization technique. Before L-dopa, mesocortical blood flow contralateral to the patients' symptoms was significantly less than controls (p less than 0.003), suggesting a specific abnormality in the cortical dopaminergic projection from the ventral tegmental area. In addition, right and left pallidal blood flow were significantly less tightly coupled in patients than controls (p = 0.0312). After L-dopa, the mesocortical blood flow remained below normal, whereas pallidal blood flow was no longer significantly different from controls (p greater than 0.05).
mesh_terms: D000328:Adult; D000368:Aged; D001345:Autoradiography; D002421:Caudate Nucleus / Q000098:blood supply; D002540:Cerebral Cortex / Q000098:blood supply; D002560:Cerebrovascular Circulation / Q000187:drug effects; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology; D011699:Putamen / Q000098:blood supply; D013788:Thalamus / Q000098:blood supply; D014055:Tomography, Emission-Computed
chemical_list: D007980:Levodopa