- Symptomatic patients (TIA or stroke) in the vertebrobasilar territory.
- Conventional or CT angiographic demonstration of50% stenosis or occlusion of extracranial or intracranial vertebral, or basilar, arteries.
- Symptoms within 60 days of enrollment.
- Age 18 and above.
- Able to provide informed consent.
1. Neurologic criteria:
- Major disabling stroke prohibiting the ability to return for follow-up assessment.
- Any neurological disease which would confound follow-up assessment.
2. Medical criteria
- Any severe co-morbidity condition with less than 12 month life expectancy.
- Known cardiac disease associated with cardioembolic risk specifically atrial fibrillation, prosthetic valves, endocarditis, left atrial/ventricular thrombus, cardiomyopathy with EF < 25%, cardiac myxoma.
- Blood dyscrasias, specifically polycythemia vera, essential thrombocytosis, sickle cell disease.
3. Disease criteria
- Non-atherosclerotic disease vertebrobasilar disease including dissection, fibromuscular dysplasia, vasculitis, radiation induced vasculopathy.
- Unilateral vertebral stenosis or occlusion.
4. Patient criteria
- Unable or unwilling to undergo MRI.
- Unable to undergo cerebral angiography.
- Concurrent participation in an interventional trial for treatment of vertebrobasilar disease.