To explore the safety and feasibility of intra-arterial neuroprotective strategy in acute ischemic stroke patients who missed recanalization operation.

Inclusion Criteria:

1. Age ≥18 years;
2. Major neurologic deficits: 6≤NIHSS≤20;
3. Missing recanalization therapy (IVT or EVT) or progressive stroke, which was defined as symptoms worsen in 48 hours (an increase in NIHSS more than 4);
4. Premorbid mRS 0 or 1;
5. Signed informed consent.

Exclusion Criteria:

1. Modified Rankin Score >2 caused by a history of prior stroke;
2. Patients who underwent intravenous thrombolysis or Endovascular treatment;
3. Coagulation disorders, systematic hemorrhagic tendency, thrombocytopenia （ <80000/mm3;
4. Severe hepatic or renal dysfunction, increase in ALT or AST (more than 2 times of upper limit of normal value), increase in serum creatinine (more than 1.5 times of upper limit of normal value) or requiring dialysis;
5. Severe hypertension (systolic blood pressure over 200mmHg or diastolic blood pressure over 110 mmHg);
6. Unsuitable for this clinical studies assessed by researcher.