SINGLE-PHOTON EMISSION COMPUTED-TOMOGRAPHY USING HEXAMETHYLPROPYLENEAMINE OXIME IN THE PROGNOSIS OF ACUTE CEREBRAL INFARCTION

Background and Purpose The role of single-photon emission CT (SPECT) i n the prognosis of cerebral infarction is controversial, but most stud ies report that SPECT using a variety of radiopharmaceutical agents gi ves useful prognostic information. Only one study has questioned wheth er acute perfusion deficits independently add to a valid clinical prog nostic score. This study was limited to middle cerebral artery territo ry infarcts and was negative. We present data on the prognostic utilit y of SPECT using Tc-99m-hexamethylpropyleneamine oxime (HMPAO) in cere bral infarction, unselected by site. Methods Fifty consecutive unselec ted patients admitted to the hospital with acute cerebral infarction, of whom 10 died and 7 withdrew, had SPECT performed serially at onset and at 1 week and 3 months after stroke onset using Tc-99m-HMPAO and t he NOVO 810 dedicated high-resolution head tomograph. Clinical severit y at presentation and outcome was measured with the Canadian Neurologi cal Scale and the Barthel Index. Infarct volumes were measured from bo th the SPECT and CT scans. The data for the 43 subjects who completed the study or died were evaluated to determine the most powerful progno stic measures. Predictors were the Canadian Neurological Scale score a t onset and 1 week, the Barthel Index at 1 week. the CT infarct volume typically done between 3 and 7 days after stroke onset, and the infar ct volumes at the first and second SPECT, Outcome measures were the Ca nadian Neurological Scale score and Barthel Index score at 3 months, s cored as zero for those patients who died. Results The clinical progno stic indicators correlated with the outcome measures. with coefficient s between .617 and .821 (P<.0006 in all cases). The Canadian Neurologi cal Scale score measured at 1 week was the best of these. Infarct volu mes measured from SPECT correlated less well (coefficients between -.5 18 and -.683. P<.0019 in all cases). CT infarct volume was the poorest predictor. Although SPECT infarct volumes predicted outcome, they did so less well than clinical examination. Spontaneous infarct reperfusi on did not affect outcome. Conclusions Although the measurement of inf arct volume on SPECT using Tc-99m-HMPAO provides a predictor of stroke outcome, it is not a better predictor than the Canadian Neurological Scale score.