Abstract 127: Anatomical Predictors Of Malignant Cerebral Edema Using Voxel-based Lesion Symptom Mapping

Abstract

Introduction: Prior publications indicate an increased risk of developing malignant cerebral edema in acute ischemic stroke patients with temporal lobe involvement. We examined on a voxel-by-voxel basis whether topographic locations of baseline diffusion and perfusion weighted MRI lesions could predict subsequent need for treatment of malignant cerebral edema with either decompressive hemicraniectomy (DHC) or hyperosmolar therapy (HT). Methods: We used a registry of 898 patients evaluated for acute treatment for suspected large vessel occlusion (LVO) stroke. Fifty-nine cases, receiving either DHC and/or HT and having sufficient data for evaluation, were manually matched with 59 controls for age, lesion size, and Thrombolysis in Cerebral Infarction (TICI) score. Binary masks of ADC + Tmax >6s lesions generated from automated RAPID software output were created. Lesions were co-registered to standard MNI atlas space. Voxel-based lesion symptom mapping (Version 2.55) was used to generate statistical maps of lesion contribution to malignant cerebral edema formation. Maps were thresholded to P<0.01 on basis of cluster size and permutation method. Hemispheres were combined to increase statistical power. Results and Conclusions: 118 patients were analyzed. After controlling for age, TICI score, and lesion volume, only punctate regions of the parieto-occipital lobe were found to be mildly predictive of the need for either DHC or HT (T-scores 2.5-3, p<0.01). There does not appear to be any significant topographic region of the brain involved on baseline diffusion-perfusion MRI that predicts subsequent need for treatment of malignant cerebral edema in patients with LVO stroke.