Early electroencephalography in acute ischemic stroke: Prediction of a malignant course?

ObjectiveIn patients with large middle cerebral artery (MCA) infarction space occupying brain edema may lead to a malignant course with up to 80% mortality under conservative treatment. As interventional treatment strategies must be started before the deterioration occurs predictors of a malignant course are necessary.Patients and methodsThis study reports on the results of early electroencephalography (EEG) within 24 h after onset of stroke in 25 patients suffering a large MCA infarct (12 patients with a malignant and 13 with a non-malignant course). EEG analysis was performed according well-established indicators for focal as well as global changes.ResultsOur findings indicate that the absence of delta activity and the presence of theta and fast beta frequencies within the focus predict a benign course (p < 0.05), whereas diffuse generalized slowing and slow delta activity in the ischemic hemisphere may point to a malignant course.ConclusionThis study shows that in patients suffering from large MCA infarction early EEG delivers useful information to select those patients who develop malignant edema.