Abstract WP91: Influence of Patient Age on Appearance and Enlargement of DWI Abnormal Lesion After Successful Recanalization by Mechanical Thrombectomy for Acute Ischemic Stroke

Abstract

Introduction: We have often experienced that young patients tend to have good outcome even with low DWI ASPECTS after mechanical thrombectomy for acute ischemic stroke. As a cause of this phenomenon, we made hypothesis that the appearance of DWI abnormal lesion was influenced by patient age. In this study we aimed to examine the influences of age on appearance of DWI abnormal lesion, and on its enlargement after successful recanalization by mechanical thrombectomy for large-vessel occlusion. Methods: This study included 94 acute cardioembolic stroke patients who successful recanalization (TICI2b or 3) was obtained with mechanical thrombectomy for large-vessel occlusion in our hospital from 2010 to 2018. Patients were classified into 3 groups depending on age, under 69 years old (Young group, n=20), 70 to 84 (Intermediate group, n=50), and over 85(Elderly group, n=24). DWI abnormal lesion volume was assessed before and within24hours after treatment for each group. Results: There was no difference in time from onset to recanalization between three groups. Initial DWI abnormal lesion volume in Young group was larger than that in Elderly group (51.0ml vs 10.8ml P<0.05). A similar tendency was observed regardless of the occluded blood vessel site and MRI imaging time and baseline NIHSS. The proportion of patients with the volume of DWI abnormal lesion enlarged 1.5 times or more in 24 hours after treatment in the elderly group was higher than in young group (45% VS 70.8%). In multivariate analysis, the elderly age and the time to reperfusion were related to expansion of DWI abnormal lesion, and this tendency was remarkable in ICA, MCA occlusion. Conclusions: Young age was associated with the appearance of larger initial DWI abnormal lesions.And old age was associated with the expansion of DWI abnormal lesions after successful recanalization by mechanical thrombectomy of large vessel occlusion.