Abstract WP67: Factors Associated with Reversed Discrepancy between CT and Diffusion-Weighted Imaging in Hyperacute Ischemic Stroke Patients
INTRODUCTION: In patients with hyperacute ischemic stroke, diffusion-weighted imaging (DWI) sometimes fails to detect early CT ischemic lesions showing parenchymal hypoattenuation, which is termed Reversed Discrepancy (RD). The aim of the present study was to elucidate the factors associated to the development of RD.
Method: One hundred sixty four consecutive patients with hyperacute anterior circulation ischemic stroke were enrolled. All patients underwent both MRI and CT within 3 hours of onset and before treatment. Three stroke neurologists independently and retrospectively evaluated presence of early ischemic changes in each the Alberta Stroke Programme Early CT Score (ASPECTS) region. Presence of RD was defined when the early ischemic change detected on CT was not detected on DWI. Patients’ baseline characteristics, ASPECTS on CT, ASPECTS on DWI, and modified Rankin Scale (mRS) 3 months after onset were compared between patients with RD (RD group) and without RD regions (non-RD group).
Results: RD was found in 40 (32%) patients (mean age 78.7 years; 50 % men); it was located in the basal ganglia (n=23), the cortex (n=27), and the basal ganglia plus the cortex (n=10). RD group was older (78.7±9.6 vs. 74.1±12.1 years, p=0.03), had a higher NIHSS score on admission (median, 22 vs. 11, p<0.01), a higher rate of atrial fibrillation (75% vs. 42%, p<0.01), a higher rate of ICA/MCA proximal occlusion (55% vs. 28%, p<0.01), had lower grade of ASPECTS either on CT (median 5 vs. 10, p<0.01) or on DWI (7 vs. 9, p<0.01) than non-RD group. Multivariate logistic regression analysis demonstrated that atrial fibrillation was an independent predictor of the presence of RD (odds ratio 2.47; 95% C.I. 1.05-6.12). RD group had less frequently good outcome (mRS 0-1 after 3 months) than non-RD group (15% vs. 34%, p=0.03).
Conclusions: Atrial fibrillation was related to the presence of RD. Patients with RD had unfavorable outcome.
- © 2012 by American Heart Association, Inc.