MR-based Stroke Mechanism and Future Risk Score

Inclusion Criteria: * age≥18 * Cerebral ischemic sympton with onset in 24 hours * pre mRS\<2 * All MR examination performed according to study protocol * Signed informed consent obtained from the patient or patient's legally authorized representative * Having complete medical history and clinical follow up * Imaging data can be processed Exclusion Criteria: * Intracranial hemorrhage * Pregnancy and other contraindication to MRI scan * Informed consent not obtained * Pre-existing medical, neurological or psychiatric disease that would confound the neurological, functional, or imaging evaluations * Known allergy to iodine previously refractory to pretreatment medications * Renal Failure (serum creatinine \> 2.0 or Glomerular Filtration Rate \[GFR\] \< 30) * History of sever kidney disease as an adult, including tumor or transplant surgery, or family history of kidney failure * Severe cardiac insufficiency