Please select the eligibility criteria that correspond to the clinical trial below.
Title: Combined Use of Contact Aspiration and the Stent Retriever Technique Versus Stent Retriever Alone for Recanalisation in Acute Cerebral Infarction: the Randomized ASTER2 Study
Brief Summary: Mechanical thrombectomy (MT) with a stent retriever (SR) device is now the standard intervention in ischemic stroke with large vessel occlusion. Favorable outcome is strongly associated with the successful reperfusion status. New device of MT such as contact aspiration seems promising to increase reperfusion status and clinical outcome.

The main hypothesis is to show the superiority of combining the use of contact aspiration with a stent retriever compared to a stent retriever alone in treatment of acute stroke due to proximal arterial occlusion.

The primary endpoint is the rate of perfect reperfusion score at the end of the endovascular procedure.


Options:
A: Inclusion Criteria:

1. Age 18 - 80
2. Clinical signs consistent with acute ischemic stroke
3. Prestroke Modified Rankin Score ≤ 1
4. NIHSS ≥ 8 and \< 30 at the time of randomization
5. Initiation of IV t-PA within 4.5 hours of onset of stroke symptoms (onset time is defined as the last time when the patient was witnessed to be at baseline), with investigator verification that the subject has received / is receiving the correct IV t-PA dose for the estimated weight prior to randomization.
6. Thrombolysis in Cerebral Infarction (TICI) 0-1 flow in the intracranial internal carotid artery, M1 segment of the MCA, or carotid terminus confirmed by CT or MR angiography that is accessible to the Solitaire™ FR Device.
7. Subject is able to be treated within 6 hours of onset of stroke symptoms and within 1.5 hours (90 minutes) from CTA or MRA to groin puncture.
8. Subject is willing to conduct protocol-required follow-up visits.
9. An appropriate signed and dated Informed Consent Form (as allowed according to country regulations and approved by ethics committee and/or IRB) has been obtained
10. Subject is affiliated with a social security system (if required by individual country regulations).
11. Subject meets national regulatory criteria for clinical trial participation.

Exclusion Criteria:

1. Subject who is contraindicated to IV t-PA as per local national guidelines.
2. Female who is pregnant or lactating or has a positive pregnancy test at time of admission.
3. As applicable by French law, subject who is a protected individual such as an incompetent adult or incarcerated person.
4. Rapid neurological improvement prior to study randomization suggesting resolution of signs/symptoms of stroke.
5. Known serious sensitivity to radiographic contrast agents.
6. Known sensitivity to Nickel, Titanium metals or their alloys.
7. Current participation in another investigational drug or device treatment study.
8. Known hereditary or acquired hemorrhagic diathesis, coagulation factor deficiency. (A subject without history or suspicion of coagulopathy does not require INR or prothrombin time lab results to be available prior to enrollment.)
9. Renal Failure as defined by a serum creatinine \> 2.0 mg/dl (or 176.8 μmol/l) or Glomerular Filtration Rate \[GFR\] \< 30Warfarin therapy with INR greater than 1.7.
10. Subject who requires hemodialysis or peritoneal dialysis, or who have a contraindication to an angiogram for whatever reason
11. Life expectancy of less than 90 days.
12. Clinical presentation suggests a subarachnoid hemorrhage, even if initial CT or MRI scan is normal.
13. Suspicion of aortic dissection.
14. Subject with a co-morbid disease or condition that would confound the neurological and functional evaluations or compromise survival or ability to complete follow-up assessments.
15. Subject currently uses or has a recent history of illicit drug(s) or abuses alcohol (defined as regular or daily consumption of more than 4 alcoholic drinks per day).
16. Known history of arterial tortuosity, pre-existing stent, and/or other arterial disease which would prevent the device from reaching the target vessel and/or preclude safe recovery of the device.

Imaging Exclusion Criteria:

1. Computed tomography (CT) or Magnetic Resonance Imaging (MRI) evidence of hemorrhage on presentation.
2. CT or MRI evidence of mass effect or intra-cranial tumor (except small meningioma).
3. CT or MRI evidence of cerebral vasculitis.
4. CT showing hypodensity or MRI showing hyperintensity involving greater than 1/3 of the middle cerebral artery (MCA) territory (or in other territories, \>100 cc of tissue) on presentation.
5. Baseline non-contrast CT or DWI MRI evidence of a moderate/large core defined as extensive early ischemic changes of Alberta Stroke Program Early CT score (ASPECTS) \< 6.
6. CT or MRI evidence of a basilar artery (BA) occlusion or posterior cerebral artery (PCA) occlusion.
7. CTA or MRA evidence of carotid dissection or complete cervical carotid occlusion requiring stenting at the time of the index procedure (i.e., mechanical thrombectomy)
8. Imaging evidence that suggests, in the opinion of the investigator, the subject is not appropriate for mechanical thrombectomy intervention (e.g., inability to navigate to target lesion, moderate/large infarct with poor collateral circulation, etc).
B: Inclusion Criteria:

* Age 18 and older (i.e., candidates must have had their 18th birthday)
* Groin puncture carried out within 8 hours of first symptoms
* Neuroimaging demonstrates large vessel proximal occlusion (distal ICA through MCA bifurcation, M1 or M2)
* Consenting requirements met according to French laws.
* With or without intravenous thrombolysis

Exclusion Criteria:

* Absence of large vessel occlusion on non-invasive imaging
* Known or suspected pre-existing (chronic) large vessel occlusion in the symptomatic territory
* Suspected pregnancy; if, a woman is of childbearing potential, a urine or serum beta human chorionic gonadotropin (betaHCG) test is positive.
* Severe contrast medium allergy or absolute contraindication to iodinated agents.
* Patient has severe or fatal comorbidities that will likely prevent improvement or follow-up or that will render the procedure unlikely to benefit the patient.
* Acute ischemic stroke involving posterior circulation (vertebrobasilar occlusion)
* Angiographic evidence of carotid dissection or tandem cervical occlusion or stenosis requiring treatment.
* Patients benefiting from a legal protection
* Non-membership of a national insurance scheme
* Opposition of the patient or (in case of inclusion as a matter of urgency) of the trustworthy person
C: Inclusion Criteria:

* Age \> 18 years with no upper age limit.
* Cerebral infarction in the anterior circulation
* Occlusion of the anterior circulation proven by CT angiography or MR angiography
* With or without previous Intravenous thrombolysis
* Start of thrombectomy procedure within 6 hours of symptoms onset.
* Patient expresses verbally his non-opposition to be enrolled in the study ; in case patient cannot communicate, verbal non-opposition is obtained from his close / trusted person

Exclusion Criteria:

* Absence of indication for thrombectomy
* Cons-indication for thrombectomy
* Presence of cerebral infarction of the posterior circulation
* Occlusion of the cervical carotid artery
* Allergy to x-ray contrast products
* Patient was bedridden or using a wheelchair most of the day (pre-event modified Rankin Scale score \> 3) prior to stroke
* Pregnancy or breastfeeding
* Patient under legal protection
* No affiliation to health insurance

Secondary exclusion criteria

- Lack of access route for catheterization
D: Inclusion Criteria

1. Age 18 and older
2. Clinical diagnosis of ischemic stroke and an associated score on the NIHSS of 5 or more points
3. Planned to undergo (or has undergone) intra-arterial (IA) thrombectomy and/or thrombolysis for acute hemispheric stroke. (Either as primary therapy or as adjuvant therapy following intravenous tPA treatment)
4. Planned to undergo or has undergone an MR brain scan including MR perfusion imaging (ASL \& bolus PWI) and MR angiography of the circle of Willis prior to IA therapy
5. Intra-arterial thrombectomy can be started within 90 minutes of completion of the MR perfusion scan and within 24 hours of symptom onset (Start of IA therapy is defined as the time of insertion of the femoral artery sheath; Time of brain scan is defined as the time that the scan is completed)
6. Able to obtain informed consent

Exclusion Criteria

1. Any pre-existing illness resulting in a modified Rankin Scale Score of 2 or higher prior to the qualifying stroke
2. Creatinine clearance \< 40 ml/min based on the NIDDK four-variable MDRD method (non-weight based)
3. Documented allergy to MR contrast agent
4. MRI contraindications (pacemaker, etc.)
5. Pregnancy

Answer: B