LOTUS: Global Acute Stroke Study Utilizing Penumbra System

Inclusion Criteria: * Patient age ≥ 18 and ≤ 85 * Patient experiencing acute ischemic stroke secondary to intracranial large vessel occlusion who are eligible for mechanical thrombectomy using the Penumbra System * Planned frontline treatment with aspiration utilizing Penumbra System * Present with symptoms consistent with an acute ischemic stroke within 8 hours of stroke symptom onset * National Institute of Health Stroke Scale (NIHSS) ≥ 6 * Signed informed consent per Institution Review Board/Ethics Committee * CT ASPECT score from 6 to 10 (≥ 6) or according to MR DWI ASPECT score from 5 to 10 (≥ 5) * Pre-stroke mRS 0-1 Exclusion Criteria: * Any comorbid disease or condition expected to compromise survival or ability to complete follow-up assessments through 90 days * Associated myocardial infarction or severe infection (endocarditis or sepsis) * Laboratory evidence of coagulation abnormalities, with an International Normalized Ratio (INR) or \> 3.0 or platelets count \< 40 x 10\^9/L or PTT/APTT \> 50 sec * Uncontrolled hypertension (defined as systolic blood pressure \> 185 mmHg or diastolic blood pressure \> 110 mmHg) * Baseline glucose \< 2.7 or \> 22.2 mmol/L * Seizure at the onset of stroke * Time of stroke symptom onset unknown * Females who are pregnant * Known serious sensitivity to radiographic contrast media that cannot be pre-treated * Renal failure as defined by serum creatinine \> 3.0mg/dl (264 µmol/L) * Currently participating in an investigational (drug, device, etc.) clinical trial that will confound study endpoints. Patients in observational, natural history, and/or epidemiological studies not involving intervention are eligible * CT/MRI evidence of the following conditions at screening: significant mass effect with midline shift, evidence of intracranial hemorrhage (ICH), aneurysm, or arteriovenous malformation (AVM), or intracranial tumor * . Angiographic evidence of preexisting arterial injury, such as carotid dissection, complete cervical carotid occlusion, or vasculitis. * Angiographic evidence of occlusions in multiple vascular territories (e.g., bilateral anterior circulation, or anterior circulation/vertebrobasilar system) as confirmed on CTA/MRA, or clinical evidence of bilateral strokes or strokes in multiple territories * Excessive arterial tortuosity that would prevent the device from reaching the target vessel