This is a prospective, randomized, single blind, concurrent controlled, multi-center study. Patients presenting with symptoms of acute ischemic stroke who have evidence of a large vessel occlusion in the cerebral circulation.

This is a prospective, randomized, single blind, concurrent controlled, multi-center study. Patients presenting with symptoms of acute ischemic stroke who have evidence of a large vessel occlusion in the cerebral circulation will be assigned to either the Tianyi Revascularization Device or Solitaire FR Revascularization Device. Each treated patient will be followed and assessed for 3 months after randomization. Up to 238 evaluable patients at up to 18 centers presenting with acute ischemic stroke in vessels accessible to the Revascularization Device for revascularization within 8 hours of symptom onset. The hypothesis to be tested is that the safety and effectiveness of the Tianyi Revascularization Device for the revascularization of large vessel occlusion is not inferior to the Solitaire FR Revascularization Device.

Inclusion Criteria:

1. aged 18-85 years
2. within 8 hours after symptom onset
3. The results showed that the scores of ASPECTS ≥6, 0<NIHSS<30 , and mRS <2 ;
4. caused by a large vessel occlusion of the anterior circulation (internal carotid artery or the M1 and M2 segments of MCA and the A1 and A2 segments) cerebral artery confirmed by DSA;
5. Signed informed consent.

Exclusion Criteria:

Clinical exclusion criteria:

1. Patients with epileptic seizure during stroke;
2. Patients with life expectancy less than 90 days;
3. Patients with intracranial hemorrhage or subarachnoid hemorrhage on the same side in recent 3 months;
4. Previous history of intracranial tumor, cerebral arteriovenous malformation or aneurysm without surgical treatment
5. Patients with a history of cerebral infarction or myocardial infarction or uncontrolled serious infectious diseases (such as endocarditis or septicemia) in recent 3 months;
6. Patients with gastrointestinal or urinary tract bleeding in the past three weeks;
7. Patients who have participated in clinical trials of other drugs or devices and have not been withdrawn from the group within the first one months of the screening period of this trial;
8. Patients with serious mental history, heart, liver, lung and kidney failure or other serious diseases;
9. Patients with active bleeding or known bleeding tendency (INR>3.0 or platelet count<40*10^9/L or APTT>50 seconds);
10. The blood glucose which could not be controlled by drugs was less than 2.7 mmol/L or more than 22.2 mmol/L;
11. Patients with hypertension beyond the control of drugs (systolic blood pressure >180 mmHg, or diastolic blood pressure >105 mmHg);
12. Females who are pregnant or in lactation;
13. Patients who are known to be allergic or resistant to contrast agents, anesthetics, anticoagulants, antiplatelet drugs and nickel-titanium;
14. Patients who have undergone major surgical operations in the past month;
15. Other cases with unknown onset time or unsuitable for inclusion in the group judged by researchers;other conditions not suitable for inclusion judged by the researcher;

Imaging exclusion criteria

1. Patients with intracerebral hemorrhage confirmed by CT (except for microbleeds. At the discretion of each Investigator);
2. ASPECTS <6 points on head CT;
3. Patients with common carotid artery occlusion who are known or suspected to be chronic occlusion;
4. DSA showed that bilateral carotid system was occluded at the same time;
5. DSA showed (or highly suspected) carotid dissection or arteritis;
6. DSA showed that the vascular route was tortuous, and the device was difficult to reach the target position or recover;
7. Subjects who are not eligible for inclusion after imaging review in the group judged by researchers.