The primary objective of the study is to gather safety and effectiveness data in support of the Citadel Embolization Device for the treatment of intracranial aneurysms. Secondary objectives are to gain physician experience and expert clinical feedback on the design features of the Citadel Embolization Device to inform possible iterative design changes. The primary safety endpoint of this study 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.

The 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 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. The secondary safety endpoint of this study is any stroke event occurring through 12 months post-procedure, where a stroke event is defined as: 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.

Procedural
Data will be collected on the following variables at the time of index procedure: Procedural success (per subject) at the target site during index procedure Device success (per device) at the target site during index procedure Post procedure aneurysm occlusion (Raymond 1, 2, 3a, or 3b) Use of coils
Use of stents and other adjunctive neurovascular devices or implants Procedure duration
Fluoroscopic duration
Procedural complications

Clinical and Angiographic
Data will be collected on the following post-index procedure outcomes through 12 months per the Study Visit and Assessment Schedule: Recanalization
Parent artery stenosis at the target aneurysm location (50% stenosis) Raymond Class 1, 2, 3a, or 3b
Progressive occlusion at the target aneurysm location Target aneurysm retreatment
Quality of Life (EQ-5D-5L)
Barthel Index

You may be eligible for this study if you meet the following criteria:

• Conditions: Medical Research
• Age: - 99 Years
• Gender: All