• Age ≥18.

• Clinical signs consistent with an acute ischemic stroke and randomization no later than 23 hours after the time last known to be well.

• CTP, CTA or enhanced MRA within 1 hour before randomization showed that the offending vessel was isolated internal carotid artery occlusion, namely occlusion of C1-C6 segments (according to Bouthillier's segmentation) at any location. There was no ipsilateral intracranial branch occlusion (T or L shape of internal carotid artery, M1 or M2 segment of middle cerebral artery, A1 or A2 segment of anterior cerebral artery, P1 or P2 segment of posterior cerebral artery).

• Neurological deficit with a NIHSS of \>5, or ≤5 points with disabling symptoms (complete hemianopsia, severe aphasia, neglect, any limb weakness that cannot sustain resistance to gravity, and functional loss that is considered by doctors and patients to be potentially disabling by clinical evaluation).

• Mismatch: target Mismatch Profile on CT perfusion or MRI (ischemic core volume is \< 70 ml, mismatch ratio is ≥1.8 and mismatch volume is ≥15 ml); clinical-imaging mismatch defined as an ASPECTS score of more than 5, was present if perfusion data were not available or imaging quality was poor enough to be interpreted.

• mRS Score before stroke ≤2.

• Patient/Legally Authorized Representative has signed the Informed Consent form.