SPONTANEOUS REPERFUSION AFTER ISCHEMIC STROKE IS ASSOCIATED WITH IMPROVED OUTCOME

Background and Purpose-The rationale behind thrombolytic therapy in ac ute ischemic stroke is penumbral salvage by rapid restoration of cereb ral blood Row. The relationship, however, between early reperfusion (p otentially composed of both nutritional and nonnutritional components) and outcome remains unclear. Methods-To establish the relationship be tween reperfusion parameters and outcome variables (Canadian Neurologi cal Scale, Barthel Index, outcome CT scans), we used Tc-99-hexamelhylp ropyleneamine oxime (Tc-99-HMPAO) single-photon emission CT (SPECT) to examine 41 acute ischemic stroke patients. All patients had at least 2 SPECT studies (24 with 3 studies), and none had been treated with th rombolytic or other acute investigational drugs. Results-A total of 10 6 studies were performed. Mean time to acute study was 9.2 hours; that for subacute study was 42 hours and for outcome study was 150 days. H ypoperfusion (HP) volumes at each of the 3 time points correlated with outcome clinical state and final infarct size. Both early reperfusion (61% of patients) and nutritional reperfusion alone (56%), which is e arly reperfusion maintained at outcome, were associated with improveme nt in clinical state and better functional outcome. Early HP volume ch ange (acute minus subacute HP volume)and total E-TP volume change (acu te minus outcome HP volume) also correlated with clinical improvement and better outcome. Conclusions-This study establishes the benefit of spontaneous reperfusion after ischemic stroke and emphasizes the progn ostic value of HP deficit volumes. Tc-99-HMPAO SPECT may be used to sc reen patients and group them according to perfusion deficit in acute s troke trials, thereby decreasing patient numbers required to show drug effect.