Carotid artery stenting (CAS) prevents stroke but carries risks of perioperative cerebral embolism. Transcranial Doppler (TCD) ultrasound can detect microemboli during CAS and may offer therapeutic benefits through ultrasound-enhanced thrombolysis. Trials like SONOBUSTER and SONOBIRDIE suggest TCD reduces new brain infarctions during carotid procedures. The TCD-ICAS trial will investigate whether TCD application during and after CAS reduces perioperative cerebral emboli and improves outcomes.

Inclusion Criteria:

• Age ≥ 40 years old;
• Patients with severe stenosis of the internal carotid artery;
• Planned for carotid artery stent;
• Modified Rankin Scale score ≤ 2;
• The subject has adequate temporal bone windows to undergo TCD, and the blood flow signal of the middle cerebral artery is detectable.;
• Signed informed consent by patient or their legally authorized representative.

Exclusion Criteria:

• Comorbid conditions with severe infections or severe diseases of the liver, kidney, hematopoietic system, endocrine system, etc.;
• Occurrence of intracranial hemorrhage (cerebral parenchymal hemorrhage, subarachnoid hemorrhage, subdural/epidural hemorrhage) within 90 days prior to enrollment;
• Severe hematological disorders or significant coagulation abnormalities;
• Pregnant or breastfeeding women;
• Participation in another clinical trial within the past 3 months or ongoing participation;
• Any other circumstances deemed by the investigator as unsuitable for participation in this clinical study.