99m Technetium-Ethyl-Cysteinate-Dimer Single-Photon Emission CT Can Predict Fatal Ischemic Brain Edema

Abstract

Background and Purpose —We sought to study the prognostic value of early 99m technetium–ethyl-cysteinate-dimer single-photon emission CT ( 99m Tc-ECD SPECT) for fatal ischemic brain edema in patients with middle cerebral artery (MCA) stroke compared with the prognostic value of CT and of clinical findings. Methods —We prospectively studied 108 patients clinically, with 99m Tc-ECD SPECT, and with CT within 6 hours of symptom onset (Scandinavian Stroke Scale <40 points) appropriate to MCA ischemia. The follow-up consisted of Scandinavian Stroke Scale and CT on days 1 and 7, Barthel Index, and Modified Rankin Scale after 3 months. An activity deficit of the complete MCA territory on the SPECT scans and a parenchymal hypoattenuation of the complete MCA territory on CT scans were considered as predictors for a fatal MCA infarction due to mass effect and midbrain herniation. Results —In 11 of 108 patients (10%), the MCA infarction was the cause of death. The sensitivity of SPECT for fatal outcome was 82% in both visual and semiquantitative analyses, while specificity was 98% and 99%, respectively. The sensitivity and specificity of baseline CT were 36% and 100%, respectively; the sensitivity and specificity of clinical findings (Scandinavian Stroke Scale, depressed level of consciousness, gaze deviation) varied from 36% to 73% and from 45% to 88%, respectively. In a multivariate logistic regression model, only SPECT findings were found to be independent predictors of malignant MCA infarction/death. Conclusions —We were able to identify patients with fatal MCA infarction with high accuracy by using 99m Tc-ECD SPECT within 6 hours of stroke onset. This technique offers great potential to select stroke patients for specific therapies, eg, decompressive hemicraniectomy, soon after onset of symptoms.