Metabolic and circulatory evaluation of cerebral ischemic accident in humans by positron emission tomography: a pilot study with almitrine-raubasine.

Positron emission tomography and oxygen-15 were used to evaluate the effect of almitrine-raubasine combination on cerebral blood flow and oxidative metabolism in patients with cerebral ischemia. In five patients aged between 58 and 74 years, with a cerebral ischemic accident in the territory of the middle cerebral artery, blood flow rate, oxygen metabolic rate, and cerebral oxygen extraction were measured before and after a 90-min intravenous perfusion of almitrine bismesilate 15 mg and raubasine 5 mg. Investigations were performed from day 2 to day 7 after stroke occurred. One patient showed evidence of initial relative luxury perfusion, the degree of which was reduced by such combined treatment. The other four patients had a focal reduction in cerebral blood flow and oxygen consumption prior to treatment. The statistical analysis of three cerebral areas (epicenter of lesion, anterior and posterior juxtalesional areas, and homologous heterolateral areas) showed a 3.6% increase in oxygen metabolic rate at the epicenter, when both hemispheres were taken together, and a significant increase in cerebral blood flow in all three areas (3% on the healthy hemisphere, 13% on the injured hemisphere). These changes were greater in some patients than in others. This suggests that heterogeneity of drug responses may correspond to the heterogeneity of the initial status.