The study is a prospective multicentre registry study. Patients admitted to 10 stroke centres nationwide from September 2022 to September 2025 with acute ischaemic stroke due to large vessel occlusion considering underlying ICAS and treated with emergency endovascular thrombolysis were included for analysis. Patients who met the general inclusion criteria underwent thrombectomy and the necessary remedial treatment.

The focus of this trial is to investigate the neuroprotective effects of endovascular hypothermia on the refractory disease of large vessel occlusion with underlying ICAS by performing different modes of endovascular interventions including stenting, balloon dilationand balloon dilation combined with stenting in patients who meet clinical and imaging criteria. The clinical prognosis of patients with different treatment modalities will be followed up to provide high quality clinical evidence to guide the interventional treatment of potential large vessel occlusions in ICAS. The main objectives of the study were to establish a prospective cohort of acute large vessel occlusions with potential ICAS treated with endovascular therapy based on the specific etiology of stroke with a high prevalence of intracranial atherosclerotic stenosis in the Chinese population; to explore the efficacy and safety of endovascular therapy for acute ischaemic stroke with potential ICAS; to investigate the use of different endovascular treatment modalities for acute ischaemic stroke with potential ICAS in the Chinese population; and to explore the neuroprotective effects of selective endovascular hypothermia on large vessel occlusions with potential ICAS. To explore the neuroprotective effect of selective endovascular hypothermia on large vessel occlusion in potential ICAS. To provide objective data and theoretical support for the choice of treatment for large vessel occlusion in underlying ICAS

Inclusion Criteria:

• CT scan to exclude intracranial haemorrhage；CT angiography (CTA), magnetic resonance angiography (MRA) or digital subtraction angiography showing occlusion of the distal intracranial carotid artery or the first segment of the middle cerebral artery；ELVO with a base ICAS of > 70%；Mechanical thrombectomy within 6h after symptom onset in ischemic stroke；NIHSS≥6；receiving endovascular treatments；informed consent form signed by the patient or their legal representatives.

Exclusion Criteria:

• Hemorrhagic body, coagulation factor deficiency or oral anticoagulant therapy(INR > 3.0)；Baseline platelet count <50,000/µL；Baseline blood glucose <50mg/dL or >400mg/dL；Intractable hypertension(systolic blood pressure >220 mmHg or diastolic blood pressure >110 mmHg) that cannot be controlled by medication；Patients intubated without a NIHSS score assessed by a neurologist or emergency physician prior to intubation；Stroke attack with epilepsy affecting baseline NIHSS score；End-stage diseases leading to less than one year of expected survival for patients；Severe allergy to contrast media；Patients with renal insufficiency (blood creatinine ≥ 3 mg/dL)；Female patients who are pregnant or breastfeeding；The patient is participating in other drugs or device studies that may affect this study；Patient with cerebral vasculitis

Patients with acute cerebral infarction with underlying intracranial artery stenosis receiving endovascular treatment