RESCUE-M2O trial is a prospective, open label, blinded endpoint (PROBE), two-arm, randomized, controlled, post-market study to assess the efficacy and safety of endovascular therapy for acute ischemic stroke with occlusion of the M2 segment of the middle cerebral artery.

Inclusion Criteria:

1. Acute cerebral infarction
2. Aged 18-84 years
3. NIHSS score at admission ≥ 8
4. Prestroke mRS scores of 0-1 (able to carry out all usual activities)
5. Occlusion of the M2 segment of MCA on digital subtraction angiography
6. ASPECTS ≥ 8 or DWI-ASPECTS ≥ 8
7. Ineligible or failed intravenous tPA (no recanalization within 30 min after injection)
8. Randomization can be completed within 24 h from the last known well time
9. EVT can be initiated within 30 min from randomization.
10. The patient or their legally authorized representative has signed the informed consent form.

Exclusion Criteria:

1. Occlusion of the anterior temporal artery, duplicate M1, or accessory M1
2. Occlusion of multiple major intracranial arteries
3. Difficulty in endovascular access due to tortuous vascular anatomy
4. Significant mass effect with midline shift on CT (or MRI)
5. Known allergy (more severe than skin rash) to contrast agents
6. Evidence of acute intracranial hemorrhage on CT (or MRI)
7. Pregnant or potentially pregnant
8. Clinical evidence of chronic occlusion
9. High risk of hemorrhage (platelet < 40,000/ul, APTT > 50 sec or PT-INR > 3.0)
10. Participating in any other therapeutic investigational trial
11. Judgment of the investigator to be non-compliant or uncooperative during the study