VALUE OF SINGLE-PHOTON EMISSION-COMPUTED TOMOGRAPHY IN ACUTE STROKE THERAPEUTIC TRIALS

Background and Purpose: New therapeutic interventions for acute ischem ic stroke are aimed at improving cerebral blood flow in the first 3 to 6 hours after symptom onset. Single-photon emission-computed tomograp hy (SPECT) performed in the setting of clinical therapeutic trials may give us a better understanding of the physiological response to new f orms of treatment and could impact acute management decisions. Methods : We prospectively studied 15 patients with hemispheric ischemic strok e with SPECT within 6 hours of symptom onset and again at 24 hours. Th e ischemic defect was assessed in a semiquantitative manner that used computer-generated regions of interest (SPECT graded scale). This meas ure was correlated with clinical presentation (National Institutes of Health [NIH] Stroke Scale), initial clinical course (change in NIH Str oke Scale), long-term outcome (Barthel Index at 3 months), and complic ations of cerebral hemorrhage and edema. Results: The severity of the SPECT graded scale on the admission scan correlated with the severity of neurological deficit (admission NIH Stroke Scale) (P<.05) and was p ositively associated with poor long-term outcome as measured with the Barthel Index (P<.001) and the complications of cerebral hemorrhage an d massive cerebral edema (P<.005). In fact, there was a threshold valu e for the SPECT graded scale above which all patients suffered poor lo ng-term outcome and the complications of cerebral hemorrhage and edema . Conclusions: The measurement of an ischemic defect using SPECT is a valid assessment of hemispheric stroke severity in the hyperacute sett ing and may be useful for selecting or stratifying patients in clinica l therapeutic trials.