Inclusion Criteria:

Clinical

• Signs and symptoms consistent with an acute posterior circulation ischemic stroke.
• Baseline modified Rankin Scale (mRS) score ≤ 2 prior to qualifying stroke.
• Subjects age is 18-89 years.
• Baseline National Institutes of Health Stroke Scale Score > 4 and remains > 4 immediately prior to thrombectomy treatment.
• Stroke symptoms began within 48 hours of thrombectomy treatment. Stroke onset is defined as the time the patient was last known to be at his/her neurologic baseline. Wake-up strokes are eligible if they meet the above time limits.
• Endovascular thrombectomy for PCLVO planned as standard-of-care therapy.
• Time of arterial puncture (femoral or radial artery) occurred (or expected to occur) within 90 minutes of CT or MR imaging study completion.
• Patient or Legally Authorized Representative has signed the study Informed Consent form.

Imaging

• Planned to undergo standard neuroimaging evaluation by computed tomography (CT) or magnetic resonance (MR) imaging that includes CT or MR angiography or the intracranial circulation and cerebral perfusion imaging prior to thrombectomy.
• .Vertebral artery or basilar artery occlusion on CTA or MRA. (Alternative assessment (if MRA/CTA technically inadequate or > 90 minutes old): Tmax>6s perfusion deficit consistent with a vertebral or basilar artery occlusion).

Exclusion Criteria: 

Clinical

• Other serious, advanced, or terminal illness (investigator judgment) or life expectancy is less than 6 months.
• Pre-existing medical, neurological, or psychiatric disease that would confound the neurological or functional outcomes evaluation.
• Endovascular treatment that primarily involves angioplasty or stent placementt.
• Any condition that, in the opinion of the investigator, precludes an endovascular procedure or poses a significant hazard to the subject if an endovascular procedure was performed.

Imaging

• Acute symptomatic arterial occlusions in more than one vascular territory on CTA (ie – associated anterior circulation LVO of the internal, middle, or anterior cerebral artery.
• Evidence of intracranial tumor (except small meningioma), acute intracranial hemorrhage, neoplasm or arteriovenous malformation.
• Mass effect with significant herniation above the cerebral tentorium or below the foramen magnum.
• Intracranial stent implanted in the same vascular territory that precludes safe deployment/removal of neurothrombectomy device.

Eligibility last updated 8/1/22. Questions regarding updates should be directed to the study team contact.