Citadel Embolization Device Study

The purpose of this study is to gather safety and effectiveness data on Stryker Neurovascular's Next Generation Target Detachable Coil (hereafter referred to as the Citadel Embolization Device), when used with Target Detachable Coils, in the treatment of wide-neck intracranial aneurysms.

In this study, use of the Citadel Embolization Device will be limited to a population of patients with unruptured or ruptured wide-neck aneurysms who meet all study eligibility criteria. The Citadel Embolization Device is intended to endovascularly obstruct or occlude blood flow in intracranial aneurysms.

The Citadel Embolization Device is intended to endovascularly obstruct or occlude blood flow in intracranial aneurysms.

The Citadel Embolization Device is intended to endovascularly obstruct or occlude blood flow in intracranial aneurysms.

Primary Safety Endpoint is stroke-related neurologic death, or major ipsilateral or disabling stroke in the territory supplied by the treated artery

Occurring within 12 months post-procedure as adjudicated by an independent Clinical Events Committee (CEC) With major ipsilateral stroke defined as a stroke associated with an increase in NIHSS score ≥ 4 points persisting ≥ 24 hours, and; With disabling stroke defined as a stroke that results in a modified Rankin Scale (mRS) score ≥ 3 assessed at a minimum of 90 days post-stroke event.

Primary Effectiveness Endpoint of this study is adequate aneurysm occlusion without retreatment or significant parent artery stenosis (>50% stenosis).

The determination of adequate aneurysm occlusion using Raymond-Roy classification will be made if either of the following criteria in the description are met: -100% occlusion (Raymond Class I) demonstrated by Digital Subtraction Angiography (DSA) measurement at 12 months (± 3 months) post-procedure, or -Stable Raymond class II demonstrated on 2 serial imaging measurements using Contrast-Enhanced Magnetic Resonance Angiography (CE-MRA) and/or DSA obtained a minimum of 6 months (± 1 month) apart. Post-procedure and 12-month imaging must be completed with DSA.

Secondary Safety Endpoint of this study is any stroke event occurring through 12 months post-procedure, where a stroke event is defined as per what is noted in the description.

-Rapidly developing clinical signs of focal (or global) disturbance of cerebral function lasting more than 24 hours with no apparent cause other than of vascular origin, including ischemic stroke and/or hemorrhagic stroke (i.e., intraparenchymal hemorrhage [IPH], subarachnoid hemorrhage [SAH], subdural hemorrhage [SDH], epidural hemorrhage [EDH]) accompanied with radiological evidence.

Inclusion Criteria: Age is ≥18 and ≤80 years Has a single, unruptured or ruptured target intracranial aneurysm that is suitable for endovascular treatment Definition: For the purposes of this study, a ruptured intracranial aneurysm is defined as one with CT/MRI/LP evidence of subarachnoid hemorrhage attributed to the index aneurysm within the last 60 days. Aneurysm morphology is saccular Aneurysm size is between 6-12 mm Has a wide-neck, saccular aneurysm, either bifurcation or sidewall, with a dome to neck ratio <2 or neck ≥4 mm If the target intracranial aneurysm is classified as ruptured, patient must be neurologically stable with a Hunt & Hess Score of 1 or 2. Must be willing to comply with protocol required procedures and follow up Subject or LAR must be willing to sign and date an IRB approved written informed consent prior to initiation of any screening or study procedures Exclusion Criteria: Target aneurysm has been previously treated Target aneurysm is in any extradural location, including the extradural cavernous segment Has vessel characteristics, tortuosity or morphology or unfavorable aneurysm morphology (e.g., determined from baseline or preprocedure imaging, or which may be evidenced by excessive resistance felt during the procedure) that would preclude safe endovascular access to the target aneurysm necessary for treatment with the study device Has significant intracranial atherosclerotic disease or stenosis determined from baseline or pre-procedure imaging If the target intracranial aneurysm is classified as ruptured, patient is neurologically unstable or has a Hunt & Hess Score of ≥ 3 Has a history of intracranial vasospasm not responsive to medical therapy Has undergone coiling or stenting of a non-target intracranial aneurysm within 30 days prior to study treatment or has a non-target intracranial aneurysm that is expected to be treated within 12 months following the treatment of the target aneurysm Treatment with flow diverting stent implant is anticipated A planned, staged procedure is anticipated Has Moya-Moya disease, arteriovenous malformation(s), arteriovenous fistula(e), intracranial tumor(s), intracranial hematoma(s), any other intracranial vascular malformation, or any previous major intracranial surgery Has had a recent (within 90 days) ischemic stroke, TIA, or intracranial hemorrhage Has a baseline mRS score ≥2 Has a known coagulopathy or is on chronic anticoagulant therapy Is pregnant or intends to become pregnant during the study or is breastfeeding Is concurrently involved in another study that could affect outcomes of IA treatment Has evidence of active cancer, terminal illness, high risk of embolic stroke, atrial fibrillation, significant co-morbidities, major surgery ≤ 30 days pre-procedure, psychiatric disorders, substance abuse, or a life expectancy of less than 5 years Has a contraindication to angiography, radiographic contrast agents, or any medications that are typically used during the procedure, and any other contraindications listed in the Investigational DFU