Inclusion Criteria- Symptomatic status: as evidenced by TIA or non-severe stroke within the past 12 months attributed to 70% to 99% stenosis of a major intracranial artery (carotid artery, MCA stem [M1], vertebral artery, or basilar artery).
- Degree of stenosis: 70%-99%; (Stenosis must be confirmed by catheter angiography for enrollment in the trial,WASID method)
- Age:30-80 years;
- No fresh infarctions identified on MRI (indicated as high signals on DWI series) upon enrollment
- No massive cerebral infarction (>1/2 MCA territory), intracranial hemorrhage, epidural or sub-dural hemorrhage, and intracranial brain tumor on CT or MRI scan
- mRS scale score of <=2
- Target vessel reference diameter must be measure d to be 2.00 mm to 4.50 mm; target area of stenosis is <=14 mm in length
- Patient is willing and able to return for all follow-up visits required by the protocol
- Patient understands the purpose and requirements of the study, can make him/herself understood, and has signed informed consent.
Exclusion Criteria- Untoward reaction to anesthesia.
- Any condition that precludes proper angiographic assessment or makes percutaneous arterial access unsafe.
- Tandem extracranial or intracranial stenosis that is proximal or distal to the target intracranial lesion
- Previous treatment of target lesion with a stent, angioplasty, or other mechanical device.
- Any aneurysm proximal to or distal to stenotic intracranial artery. Intracranial tumor (except meningioma) or any intracranial vascular malformation
- Computed tomographic or angiographic evidence of severe calcification at target lesion
- Stroke of sufficient size (>5cm on CT or MRI) to place patient at risk of hemorrhagic conversion during the procedure.Hemorrhagic transformation of an ischemic stroke within the past 15 days.
- Previous spontaneous intracerebral (parenchymal) or other intracranial (subarachnoid, subdural, or epidural) hemorrhage within 30 days
- Untreated chronic subdural hematoma >5 mm in thickness
- Intracranial arterial stenosis related to arterial dissection, moya-moya disease or any known vasculitic disease;
- MI within previous 30 days
- Any episode of paroxysmal atrial fibrillation within the past 6 months, or history of paroxysmal atrial fibrillation requiring chronic anticoagulation
- Intolerance or allergic reaction to any of the study medications, including aspirin, clopidogrel, heparin, nitinol, and local or general anaesthesia History of life-threatening allergy to contrast dye. If not life-threatening and can be effectively pretreated, patient can be enrolled at physicians discretion
- Recent GI bleed that would interfere with antiplatelet therapy. Active bleeding diathesis or coagulopathy; active peptic ulcer disease, major systemic hemorrhage within 30 days, active bleeding diathesis, platelets count <125,000, hematocrit <30, Hgb <10 g/dl, uncorrected INR >1.5, bleeding time >1 minute beyond upper limit normal, or heparin-associated thrombocytopenia that increases the risk of bleeding, uncontrolled severe hypertension (systolic BP>180 mm hg or diastolic BP>115 mm hg), severe liver impairment (AST or ALT >3 times normal, cirrhosis), creatinine >265.2μmol/l (unless on dialysis)
- Major surgery (including open femoral, aortic, or carotid surgery) within previous 30 days or planned in the next 90 days after enrollment
- Severe dementia or psychiatric problem that prevents the patient from following an outpatient program reliably
- Pregnancy or of childbearing potential and unwilling to use contraception for the duration of this study