Head Position After Endovascular Therapy

Inclusion Criteria:

1. Clinical signs consistent with acute ischemic stroke;

2. Age ≥ 18 years old;

3. Proved anterior circulation large vessel occlusion on digital subtractionangiography (ICA, M1, M2) with/without cervical lesion (tandem);

4. NIHSS score ≥ 8 points before endovascular treatment;

5. ASPECTS score ≤ 7 points before endovascular treatment;

6. Successful vessel recanalization after endovascular treatment (defined as an eTICIscore of 2b, 2c, or 3) ；

7. The time from onset to randomization ≤ 24 hours (the onset time is defined as thelast normal time);

8. Written informed consent is obtained from patients and/or their legalrepresentatives.

Exclusion Criteria:

1. Pre-stroke mRS score>1 point;

2. Patients with acute occlusions in multiple vascular territories (e.g. bilateralanterior circulation, or anterior/posterior circulation);

3. Currently in pregnant or lactating or serum beta HCG test is positive on admission;

4. Contraindications to a flat head position;

5. Any terminal illness with life expectancy less than 6 months;

6. Participating in other clinical trials;

7. Patients with a preexisting neurological or psychiatric disease that would confoundthe neurological functional evaluations;

8. Unlikely to be available for 90-day follow-up.