1, CT and MRI examination can show ischemic infarction or hemorrhagic infarction changes combined with hemorrhagic infarction highly support cerebral embolism many patients secondary to hemorrhagic infarction clinical symptoms and aggravation within 3-5 days of onset reexamination CT can be found early to stimulate post-infarction hemorrhage timely adjustment of treatment plan MRA can find the degree of carotid artery stenosis or occlusion. 2.Lumbar puncture cerebral pressure normal cerebral pressure increase indicates large cerebral infarction hemorrhagic infarction cerebrospinal fluid can show blood or microscopic red blood cells; infected cerebral embolism cerebrospinal fluid cell count increased (early granulocytes mainly, late lymphocytes mainly); fat embolism cerebrospinal fluid can be seen fat globules. 3, electrocardiogram should be a routine examination to determine the evidence of myocardial infarction wind heart disease arrhythmia, etc. Cerebral embolism can be the first symptom of myocardial infarction is not uncommon carotid ultrasound can evaluate the degree of luminal stenosis and atherosclerotic plaque to confirm the significance of carotid origin embolism.