Early Prediction of Malignant Edema After Successful Recanalization in Patients with Acute Ischemic Stroke.

BACKGROUND Postinterventional cerebral hyperdensities are common on non-contrast-enhanced computed tomography (CT) after endovascular thrombectomy in patients with acute ischemic stroke, which may reflect blood-brain barrier damage. The disruption of the blood-brain barrier may lead to malignant brain edema. The relationship between the extent of postinterventional cerebral hyperdensities and malignant brain edema is unclear. METHODS Patients with middle cerebral artery territory infarction and successful recanalization were consecutively enrolled. Postinterventional non-contrast-enhanced CT was performed to evaluate postinterventional cerebral hyperdensities within 24 h after endovascular thrombectomy. On the basis of the areas of the Alberta Stroke Program Early CT Score, we devised the Hyperdensity on CT Score to evaluate the extent of postinterventional cerebral hyperdensities. The primary outcome was malignant brain edema, defined as the development of clinical signs of herniation (including a decrease in consciousness and/or anisocoria), accompanied by imaging evidence of brain swelling. The component of postinterventional cerebral hyperdensities was divided into contrast staining and hemorrhage on the basis of persistency. RESULTS Three hundred sixty patients were included (50.6% male, mean age 67.9 years), of whom 247 (68.6%) developed postinterventional cerebral hyperdensities and 66 (18.3%) developed malignant brain edema. After adjustment for confounders, including the component of postinterventional cerebral hyperdensities, the extent of postinterventional cerebral hyperdensities assessed by the Hyperdensity on CT Score was significantly associated with malignant brain edema (odds ratio 1.46, 95% confidence interval 1.20-1.77, p < 0.001). A Hyperdensity on CT Score greater than 3 had a sensitivity of 0.73 and a specificity of 0.87 for predicting malignant brain edema. CONCLUSIONS The extent of postinterventional cerebral hyperdensities on postinterventional non-contrast-enhanced CT was associated with malignant brain edema. The Hyperdensity on CT Score could be used to predict malignant brain edema regardless of the component of postinterventional cerebral hyperdensities.