Beyond established criteria for carotid endarterectomy (CEA), additional plaque histologic features such as a large lipid core, fibrous cap rupture, surface ulceration, and intraplaque hemorrhage have been associated with atheroembolic stroke.(1,2) It has become of great interest to identify which plaques are "vulnerable," even though not yet ruptured (ie, at risk of becoming symptomatic or at a vulnerable stage).(3) The 2-year risk of ipsilateral stroke for medically treated patients with ulcerated plaques was 73% for higher degrees of stenosis compared with 21% for all degrees.(4) We report the imaging findings of high-grade symptomatic carotid stenosis. On admission, the ultrasound study did not show any feature suggestive of a vulnerable plaque except for the degree of stenosis. However, an ultrasound examination performed 24 hours later revealed acute changes in the plaque surface, leading to urgent CEA.