sICASBLM is a prospective controlled trial, to asses the impact of improving blood lipid management on clinical outcome of moderate to severe symptomatic intracranial atherosclerotic stenosis patients (LDL-C>1.8mmol/L) without endovascular therapy.

sICASBLM aims to determine the effectiveness of conventional lipid management combined with PCSK9 inhibitors compared to conventional lipid management (atorvastatin 20-40mg or rosuvastatin 10-20mg or simvastatin 20-40mg) in reducing the incidence of recurrent stroke in patients with moderate to severe symptomatic intracranial atherosclerotic stenosis (LDL-C>1.8mmol/L) without endovascular therapy.

Inclusion Criteria:

1. Age ≥18 years
2. Symptomatic intracranial atherosclerotic stenosis of moderate to severe, did not receive intravenous thrombolysis, thrombectomy, stent implantation and other intravascular treatment
3. low density lipoprotein cholesterol > 70mg/dl (1.8mmol/L)
4. Receive 3T magnetic resonance angiography or multi-mode MR (high resolution is required), angiography can be included, and images for analysis can be obtained.
5. Lipid-lowering indications of statins
6. Signed an approved informed consents

Exclusion Criteria:

1. Contraindications to statins
2. There are contraindications to MRI examination or cannot accept MRI examination
3. Stenosis caused by vasculitis, arterial dissection and moyamoya disease
4. Patients with active bleeding or obvious bleeding tendency
5. Severe heart, lung, renal insufficiency, malignant tumor or other malignant diseases, and death is highly likely within 7 days; pregnancy or women who are lactating
6. Uncontrolled severe diabetes and hypertension
7. Other conditions inappropriate for inclusion judged by investigators