Stroke Imaging Package Study of Intracranial Atherosclerosis ( SIPS-ICAS )

1. First-ever stroke patients attributed to intracranial artery stenosis (\> 50% or occlusion) within 7 days after onset will be prospectively enrolled in our study and undergo new imaging technique package assessment at baseline. 2. The imaging technique package includes conventional cranial MRI （T1,T2,T2 FLAIR,DWI), cranial magnetic resonance angiography (MRA),high-resolution magnetic resonance (HR-MRI) and susceptibility weighted imaging (SWI) or T2\*-weighted imaging. 3. Enrolled patients are recommended to receive aggressive medical management consisted of Aspirin (100 mg daily) and Clopidogrel (75 mg daily) for 3 months and Rosuvastatin (20mg daily) for at least 6 months as well as traditional risk factors management. 4. Patients were followed up for mRS score, stroke recurrence, medication compliance and laboratory examination including blood routine tests, liver functions and creatine kinase et al at 3 months, 6 months and 12 months after stroke onset. Additionally, patients are required to retake new HRMRI imaging of brain at 6 months.Remote patient education by We-Chat will be performed. 5. Our study aims to explore the stroke mechanisms of symptomatic intracranial atherosclerosis, the dynamic changes under aggressive medical treatment and their associations with clinical events using conventional MRI sequences plus HR-MRI.