Abstract T P48: Neuroimaging Markers of Swelling Predict Outcome After Acute Ischemic Stroke

Introduction: In malignant infarction, brain edema leads to secondary neurological deterioration and poor outcome. We investigated whether swelling is associated with outcome in a broader range of stroke severity. Methods: Two research cohorts (NBO and EPITHET) comprising 98 acute stroke subjects with prospective serial brain magnetic resonance imaging (MRI) were analyzed. The categorical presence of swelling and/or infarct growth (IG) was assessed on diffusion weighted MRI (DWI) by comparing baseline and 3-5 day follow-up scans. IG was defined using the ASPECTS system (small IG = decrease in ASPECTS ≥ 1; large IG = decrease in ASPECTS ≥ 2). The increase in lesion volume (ΔDWI) was then subdivided into swelling and IG volumes using region-of-interest analysis. The relationship of these imaging markers with outcome was evaluated using univariate and multivariate regression, with poor outcome defined as a 90 day modified Rankin Scale score of 3-6. Receiver operating characteristic (ROC) curve analysis was u...