Inclusion Criteria:

• Age ≥18 years.

• Presentation with acute ischemic stroke within 14 days of symptom onset.

• Ipsilateral extracranial carotid plaque with ≤50% stenosis by NASCET-based assessment, anatomically concordant with the index ischemic event or considered a plausible embolic source after standard etiologic evaluation.

• Ability to undergo neck MRA-VWI and brain MRI.

• Ability to provide informed consent personally or through a legally authorized representative.

• Ability to complete 30-day telephone follow-up and 90-day clinical follow-up.

Exclusion Criteria: 

• Ipsilateral carotid stenosis >50%.

• Absence of ipsilateral carotid plaque.

• Clearly established non-carotid stroke mechanisms, including atrial fibrillation or flutter requiring anticoagulation, intracardiac thrombus, mechanical heart valve, recent myocardial infarction with embolic source, lacunar small-vessel stroke pattern, intracranial stenosis explaining the infarct, cervical artery dissection, vasculitis, hypercoagulable condition judged to be the primary mechanism, or another definite stroke etiology.

• Contraindication to MRI or MRA-VWI.

• Severe baseline disability (modified Rankin Scale >3).

• Large territorial infarction involving more than one-third of the middle cerebral artery territory.

• Crescendo TIA or worsening neurologic syndrome requiring urgent non-study intervention.

• Pregnancy when MRI is not clinically appropriate per local policy.

• Any clinical condition that, in the opinion of the investigators, would make study participation unsafe or prevent reliable outcome assessment.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 06/10/2026. Questions regarding updates should be directed to the study team contact.