Abstract WP248: Cortical Microinfarcts on 3T MRI in Patients With Carotid Artery Stenosis

Abstract

Background and Purpose: There is still uncertainty about the underlying mechanism of cortical microinfarcts in patients with carotid artery stenosis. We assessed the association between cortical microinfarcts (CMIs) on 3T MRI and imaging features of carotid and brain MRI. Methods: Eighty-nine patients with >50% carotid artery stenosis on carotid ultrasound were prospectively included, and underwent both carotid and brain MRI. CMIs were rated according to pre-determined criteria based on double inversion recovery and 3D FLAIR images. Results: We identified 69 CMIs in 26 (29%) patients. Multivariate-adjusted models showed CMIs were associated with intraplaque hemorrhage, and cortical infarct but not with severe stenosis (>70%) or markers of small vessel disease (SVD) such as white matter hyperintensities and cerebral microbleeds. Among 81 patients with unilateral carotid artery stenosis, 18 patients (22%) had 52 CMIs in ipsilateral hemisphere, while 6 patients (6%) had 9 CMIs in contralateral hemisphere. The number of CMIs were significantly higher in the ipsilateral side than in the contralateral side ( P = 0.005). Conclusions: CMIs were associated with intraplaque hemorrhage, cortical infarct, and carotid artery stenosis. These findings suggest artery-to-artery emboli might be the underlying cause of CMIs in patients with carotid artery stenosis.