CAPTURE Registration Trial of the Thrombectomy System for the Treatment of Acute Ischemic Stroke.

• Subject must demonstrate clinical signs and symptoms that are attributable to the targeted lesion and are consistent with the diagnosis of acute ischemic stroke (AIS), as confirmed by a neuroradiologist (or equivalent expert), using appropriate imaging. Arterial occlusion of ICA, MCA-M1 or MCA-M2.
• Female or male subject, who, at the time of consenting, is aged between 18 and 80 years, inclusive.
• Within 6 hours of stroke symptom onset, subject must have undergone treatment initiation (vascular access through puncture or cut down).
• Signed Informed Consent Form (ICF) completed by subject or subject's legal representative.

Exclusion Criteria:

• 1. Functional dependence prior to stroke onset, defined as a pre-stroke modified Rankin Scale (mRS) score of ≥2.
• 2. Subject's baseline NIHSS score \<2 or >25.
• 3. History of severe head injury within past 90 days with residual neurological deficit, as determined by medical history.
• 4. Pre-existing neurological or psychiatric disease that would confound the neurological or functional evaluations, e.g. dementia with prescribed anti-cholinesterase inhibitor.
• 5. Seizures at stroke onset if it makes the diagnosis of stroke doubtful and precludes obtaining an accurate baseline NIHSS assessment.
• 6. Subject has a known hemorrhagic diathesis, coagulation factor deficiency; or, is on oral anticoagulant therapy and has an International Normalized Ratio (INR) >3.
• 7. Subject's baseline platelet count is \<30*10\^9/L.
• 8. Subject's baseline glucose is \<50 mg/dL (2.78 mmol/L) or >400 mg/dL (22.2 mmol/L).
• 9. Renal failure, as defined by a serum creatinine >3.0 mg/dL (264 µmol/L) [NOTE: subjects on renal dialysis may be treated regardless of serum creatinine levels].
• 10. Severe, sustained hypertension (SBP > 185 mm Hg or DBP > 110 mmHg) [if the blood pressure can be successfully reduced and maintained at the acceptable level, using medication, the patient can be enrolled].
• 11. Subject has known allergy or contraindication to one or more of the following: anti-platelet drugs; contrast dye; and/or, local or general anesthesia.
• 12. Subject has known allergy to nickel, cobalt chromium, tungsten, platinum or other metal that may be a component of a required medical device needed for treatment.
• 13. Subject is generally unsuitable for endovascular intervention or anesthesia.
• 14. Subject has had major surgery within the previous 30 days
• 15. Subject is an active participant in another drug or device treatment trial for any disease state; or, subject is expected to start participation in another drug or device trial while enrolled in this protocol.
• 16. Subject currently has infective endocarditis or other severe, active bacterial infection.
• 17. Subject's life expectancy is less than 6 months.
• 18. Female of childbearing potential who is known to be pregnant and/or lactating or who has a positive pregnancy test on admission.

Imaging Exclusion Criteria:

• 19. Subject has CT scan or MRI evidence of the following:

      • Significant mass effect with midline shift.
      • Evidence of intracranial tumor, except small meningioma.
      • Evidence of intracranial hemorrhage.
      • Evidence of internal carotid artery flow limiting dissection.
      • Suspected cerebral vasculitis.
      • Suspected aortic dissection.
      • Occlusions in multiple vascular territories (e.g., bilateral anterior circulation, or anterior/posterior circulation) or clinical evidence of bilateral strokes or strokes in multiple territories.
• 20. The presence of a large completed territorial infarction by non-contrast CT (NCCT), defined as an Alberta Stroke Program Early CT Score (ASPECTS) ≤5.

• 21. Other unusual morphology or lesion that might interfere with device use, including but not limited to the following:

      • Carotid dissection
      • Vasculitis
      • Aortic dissection
      • Aneurysm

      • No transfemoral or alternative access, such as:

        1. Severe intracranial tortuosity
        2. Severe intracranial vasospasm, unresponsive to pharmacotherapy.
        3. Other anatomical or clinical conditions contraindicated for access.
• 22. Anterior circulation strokes involving > 1/3 of the MCA territory, as determined by hypo-density on the baseline non-contrast CT, or low CBV on CT Perfusion imaging, or restricted diffusion on DWI images.
• 23. Thrombotic occlusion in the posterior circulation arteries (vertebral, basilar, etc.)
• 24. Intracranial stent implanted in the same vascular territory that would preclude the safe deployment/removal of the thrombectomy device.