CHANGES IN THE CEREBRAL AND CEREBELLAR BLOOD-FLOW IN CEREBRAL EMBOLISM

The present study was performed to elucidate the time course of the ce rebral and cerebellar blood flows and the significance of SPECT for pr edicting the outcome in cerebral embolism. Tc-99m-hexamethylpropylenea mine oxime (Tc-99m-HMPAO) SPECT was repeatedly performed in 60 patient s with unilateral cerebral embolism. The distribution of Tc-99m-HMPAO in the infarct area decreased in the acute phase, increased from 3 h t o 22 days after the stroke and then gradually and eventually decreased in the chronic stage. This tendency was observed irrespective of the thrombolytic therapy. The asymmetry index (AI) in the cerebral hemisph ere in the first 6 h and later than 30 days correlated significantly w ith activities of daily living in the chronic stage (p < 0.05). The ce rebellar AI after, but not up to 14 days also correlated with the long term outcome (p < 0.05). In conclusion, a high distribution of Tc-99m- HMPAO frequently and transiently occurs in the subacute stage of cereb ral embolism. The cerebral and cerebellar asymmetry of the Tc-99m-HMPA O distribution is an important predictive value for the outcome; howev er, the timing of SPECT is critically important.