VISSIT Intracranial Stent Study for Ischemic Therapy

Inclusion Criteria: 1. Subject has at least one neurovascular lesion (70-99%) stenosis \[internal carotid, middle cerebral, vertebral artery (C4-BA), and/or basilar artery\] symptomatic with a hard TIA or stroke attributable to the territory of the lesion within the past 30 days. An intracranial tandem lesion (50-99%) stenosis may be treated if normal artery segment is sufficient length to avoid overlapping stents. 2. Target vessel diameter / lesion length measurements are within one of the below per angiogram: * Vessel diameter is ≥ 2.0 mm and \< 2.5 mm / lesion length is ≤ 16 mm, or * Vessel diameter is ≥ 2.5 mm and \< 3.0 mm / lesion length is ≤ 18 mm, or * Vessel diameter is ≥ 3.0 mm and \< 4.5 mm / lesion length is ≤ 26 mm, or * Vessel diameter is ≥ 4.5 mm and ≤ 5.0 mm / lesion length is ≤ 31 mm 3. Subject has normal artery adjacent to each stenosis; diameter 2.0 mm - 5.0 mm 4. Subject age is 18-85 years 5. Life expectancy is at least 2 years 6. Subject 's mRS score is ≤ 3 7. Subject is available for study follow-up visits (e.g., lives within 3 hours of research center) 8. Subject is willing and cognitively able to provide Informed Consent (consent may be indicated verbally and signed by neutral witness if stroke has impaired hand or visual function) Exclusion Criteria: 1. Subject has contraindications for balloon expandable stent, e.g. * Extreme tortuosity at, or proximal to, target lesion, * More than 2 lesions with \> 50% stenosis (including vertebral ostia and common carotid disease), * Carotid or vertebral dissection 2. CT scan or MRI evidence of any of the following: * Intracranial hemorrhage of type PH1 or PH2 * Subdural or epidural hemorrhage * Mass effect, or * Intracranial tumor (except small meningioma) 3. Subject has a previous stent in the territory of the target lesion(s) 4. Subject has a previous coil or clip placed in the territory of the target lesion within 6 months 5. Subject has a potential source of cardiac embolism requiring anticoagulation therapy (e.g., atrial fibrillation, intracardiac thrombus or vegetation, significant mitral stenosis, mechanical heart valve, congestive heart failure with EF \<30%, or endocarditis) 6. Subject has concurrent intracranial pathology, e.g. * Moyamoya * Vasculitis documented by biopsy results * Ruptured Aneurysm * Unruptured aneurysm \> 7mm 7. Subject has uncontrolled hypertension (systolic \>185 mmHg or diastolic \>110 mmHg) 8. Hemoglobin \< 10 g/dL; platelet count \< 100,000; or INR \> 1.5 (e.g., use of warfarin) 9. Subject has an uncorrectable bleeding diathesis 10. Subject's neurological status is unstable and rapidly declining (NIHSS score increased \> 4 points within 48 hours prior to randomization) 11. Subject has a contraindication for combination antithrombotic treatment (e.g., clopidogrel and aspirin) such as peptic ulcer disease 12. Subject history indicates high risk of non-compliance (e.g., substance abuse, psychosocial issues, etc.) 13. Subject has a known history contraindicating contrast dye or iodine (vs. sensitivity which can be safely controlled by antihistamine, steroid, etc.) 14. Subject is pregnant or plans to become pregnant in the next 12 months 15. Myocardial infarction within past 3 months 16. Treatment with tPA or other thrombolytic agent within 48 hours prior to randomization 17. Major surgery or trauma within 2 weeks prior to randomization 18. Enrollment in another investigational device or drug study that may confound the results