（2）Pregnant or lactating women. （3）Patients with severe cardiovascular disease and poorly controlled diabetes. （4）Mental disorder. （5）Severe infection. （6）Patients who can't finish MRI examination. （7）Patients were treated with thrombolytic therapy and anticoagulant therapy, either with bleeding diathesis or coagulopathy, or aneurysm, stroke, transient ischemic attack, arteriovenous malformation in the past year.