Inclusion Criteria:  Age ≥ 18 years old Diagnosis of acute ischemic stroke Imaging confirmed intracranial large artery occlusion (LVO): intracranial internal carotid artery (ICA T/L), middle cerebral artery (MCA M1/M2), anterior cerebral artery (ACA A1/A2), basilar artery (BA), vertebral artery (VA V4), and posterior cerebral artery (PCA P1);ASPECT or PC-ASPECT ≥ 6 Initiation of any type of endovascular treatment (EVT), including intra-arterial thrombolysis, mechanical thrombectomy, angioplasty, and stenting The patient or the patient's legal representative is able and willing to sign the informed consent  Exclusion Criteria:  Isolated cervical ICA or VA occlusion; No evidence of LVO on DSA.