Atherosclerosis of craniocervical arteries are one of most important causes of stroke. Carotid artery is the most frequent site of atherosclerosis. Recent research in carotid artery covers not only morphology of lumen but also direct visualization of carotid plaque or vessel wall. Vulnerable carotid plaques share pathologic features of intra-plaque inflammation and hemorrhage. There have been reports about post-contrast SWI in the field of vascular imaging. We hypothesized SWI is so sensitive to gadolinium based contrast agent and hemorrhage that contrast-enhanced SWI can visualize vulnerable carotid plaque. The purpose of this study is to investigate gadolinium-enhanced SWI in detection of vulnerable carotid plaque and compare it with MP-RAGE and DANTE T1-SPACE. This can be used to guide proper treatment for stroke.