The objective of this study is to investgiate the safety and clinical performance of the World Diverter Emoblization Device for the endovascular treatment of wide-neck (neck width ≥ 4 mm or dome-to-neck ratio <2) or fusiform intracranial aneurysms in the internal carotid artery (ICA) from the petrous segment to the terminus arising from a parent vessel with a diameter ≥ 2.5 mm and ≤ 5.5 mm.

Inclusion Criteria:

• Age 18 22 to 80 years
• Subject, or subject's legal representative provided informed consent
• Subject agrees to the requirements of the study, including returning for required follow-up visits
• Parent artery diameter of 2.0-5.5 mm distal and proximal to the target IA
• Subject has a single target IA in the index procedure with the following characteristics: (1) Unruptured; (2) Located in the ICA from the petrous through the superior hypophyseal segments; and (3) Is a fusiform or saccular wide-necked IA with one of the following characteristics: (a) Small (< 5 mm) or medium (>5-10 mm) size with a neck width ≥ 4.0 mm or a dome-to-neck ratio of < 2; OR (b) Large (>10-25 mm) or giant (>25 mm) size

Exclusion Criteria:

• A subarachnoid or intracerebral hemorrhage in the 60 days preceding the index procedure
• A bleeding disorder or a platelet count of less than 100x103/mm3 or INR >1.5
• A contraindication to or inability to tolerate antiplatelet therapy
• An allergy to radiographic contrast agents
• An allergy to  nickel, titanium, platinum, tungsten, or stainless steel
• An allergy to local or general anesthesia
• A history of untreated atrial fibrillation, untreated/uncontrollable hypertension, or other stroke risk factors
• A history of deep vein thrombosis or pulmonary embolism
• A history of heart failure, dilated cardiomyopathy, or congenital heart conditions
• Hypercoagulopathy or a hemorrhagic or coagulation deficiency refractory to medical therapy or subject refuses treatment with blood products
• Suffered a stroke within 180 days preceding the index procedure
• Had major surgery within the 30 days preceding or planned for the 180 days following the index procedure, including but not limited to intracranial stenting or coiling
• Target aneurysm has been previously treated with clipping, coiling, or flow diversion
• Had previous stenting of or implant in parent artery proximal to the target aneurysm that could interfere with delivery or performance of study device
• Asymptomatic extradural aneurysms requiring treatment
• Contraindication to computed tomography (CT) or magnetic resonance (MR)
• An unstable neurological deficit (i.e., worsening of a clinical condition within the 30 days preceding the index procedure)
• Evidence of an active systemic infection (including COVID-19) at index procedure
• Dementia or other cognitive condition limiting their ability to participate in the study
• A condition that may limit survival to less than 12 months post-index procedure
• Serum creatinine ≥2.5 mg/dL
• Had radiation or chemotherapy treatment either currently or within the 60 days preceding the index procedure
• Current enrollment in a separate clinical trial
• Another condition(s) that, in the opinion of the Investigator, could interfere with the ability to perform a safe or effective procedure
• Current pregnancy or plan to become pregnant within the 12 months following the index procedure, or be currently breastfeeding

Angiographic Exclusion Criteria:

• Anatomy not amenable to endovascular treatment, including but not limited to severe vessel tortuosity or stenosis
• Parent vessel stenosis is >50% in the target area
• Extracranial stenosis of the carotid artery >50%
• An intracranial mass
• More than one vessel segment requiring IA treatment in the 12 months following the index procedure
• Target aneurysm is mycotic or dissecting
• Target aneurysm is at bifurcation
• Target aneurysm will require coiling in addition to flow diversion, in Investigator's opinion

Individual participant data are protected by data privacy laws and are only provided for the purposes of this study following provision of participant informed consent.