Stroke is one of the most important diseases endangering the health and quality of life of Chinese people. Acute ischemic stroke (AIS) is commonly caused by cerebrovascular stenosis or occlusion. The most effective treatment for AIS is timely and successful angiographic reperfusion.

Due to the large diameter and obvious positioning of bilateral femoral arteries, the transfemoral artery (TFA) using Seldinger's technique has been the most commonly used approach for endovascular treatment. However, recent studies have suggested that the radial artery is an ideal puncture site for cerebrovascular intervention. Small sample studies have confirmed that endovascular recanalization for acute anterior circulation large vessel occlusion via TRA has been safe and effective. Still, there are some complex approaches needed to be converted to TFA. There has been no difference in total operation duration and fluoroscopy time between TRA and TFA, but the TRA group had higher radiation dose and shorter hospital stays than the TFA group. In addition, TRA tends to be more convenient than TFA, especially for posterior circulation lesions.

However, the current studies are based on a single center with a small sample size, and there has been still a lack of large-sample randomized controlled experiments to verify the safety and effectiveness of posterior endovascular recanalization via TRA.

In this trial, acute ischemic stroke patients with large vessel occlusion in the posterior circulation within 24 hours of symptom onset or last known well will be included. After screening and baseline evaluation, eligible subjects will be randomly assigned to one of the following 2 groups in a 1:1 ratio: The experimental group will undergo basilar artery recanalization via the radial artery approach, while the control group will through the femoral artery approach. The primary endpoint of this study is the favorable functional outcome at 90 days after the endovascular recanalization (defined as mRS ≤ 3). Subgroup analyses were prespecified for the primary outcome according to sex (male or female), age (<70 years or ≥70 years and <80 years or ≥80 years), baseline stroke severity (NIHSS score 10 to 19 or ≥20), time from the estimated time of basilar-artery occlusion to randomization (<6 hours or ≥6 hours), intravenous thrombolysis (no or yes), location of basilar-artery occlusion (proximal, middle, or distal), the presumed cause of the basilar-artery occlusion (large-artery atherosclerosis, cardioembolism, or undetermined and other determined cause), intracranial atherosclerotic disease as cause of stroke (yes or no), and PC-ASPECTS at baseline (<8 or ≥8).

Inclusion Criteria:

1. Acute ischemic stroke in the posterior circulation confirmed by symptoms and imaging examinations.
2. Basilar artery occlusion confirmed by computed tomographic angiography (CTA), magnetic resonance angiography (MRA), or digital subtraction angiography (DSA).
3. Age ≥ 18 years.
4. Time from symptom onset to randomization within 24 hours of the estimated time of basilar artery occlusion.
5. Baseline NIHSS score ≥ 10 before randomization.
6. Intact dual circulation of the hand assessed by the modified Allen's test.
7. Written informed consent from patients or their legally authorized representatives.

Exclusion Criteria:

1. Pre-stroke disability with mRS score ≥ 3.
2. Pregnant or lactating women.
3. Allergic to contrast agents or nitinol devices.
4. Participation in other clinical trials.
5. Systolic blood pressure > 185 mmHg or diastolic blood pressure > 110mmHg, and can not be controlled by antihypertensive drugs.
6. Known genetic or acquired bleeding diathesis, lack of coagulation factors; or oral anticoagulant therapy with INR > 1.7.
7. Baseline lab values: blood glucose < 50mg/dL (2.8mmol/L) or > 400mg/dL (22.2 mmol/L), platelet count < 50*109 /L, or hematocrit < 25%.
8. Life expectancy less than 1 year.
9. Lost to follow-up within 90 days (e.g. no fixed residence, overseas patients, etc.).
10. Acute ischemic stroke within 48 hours after percutaneous coronary intervention, cerebrovascular intervention, or major surgery (patients can be included if more than 48 hours).
11. Clinical manifestations of central nervous system vasculitis.
12. Premorbid nervous system diseases or mental disorders hindering the assessment of the disease.
13. Diseases or anatomical abnormalities that make it difficult for radial or femoral artery puncture, sheath insertion or instrument delivery, such as local infection, anatomical abnormalities confirmed by ultrasound or other imaging examinations, previous interventional or open surgery.