The purpose of this study is to evaluate the safety and short-term effectiveness of implantation of 'Flowise Cerebral Flow Diverter' for the treatment of unruptured wide-necked cerebral aneurysm in the internal carotid artery.

Flowise is indicated for use in patients with unruptured wide-necked aneurysm in the internal carotid artery. Consecutive subject data should be collected at discharge, 1, 3, and 6 month post Flowise implantation.

Inclusion Criteria:

• Functional neurological state ≤2 mRS
• Unruptured wide-neck aneurysm in the internal carotid artery has a size >8mm, a neck ≥4mm, or dome/neck ratio <2
• Parent artery with diameter ≥3.25mm and ≤4.5mm
• Patient willing to provide written informed consent and comply with follow-up requirements

Exclusion Criteria:

• Intracranial hemorrhage within 30 days
• Untreated ruptured intracranial aneurysm
• ≥1 intracranial aneurysm except the target one requires treatment within 6 months
• Immunosuppressive disease
• Active infectious disease (e.g. endocarditis, meningitis)
• Platelet count < 100 x 103 cells/mm3
• Female of child-bearing potential who are unable to take adequate contraceptive precautions, are known to be pregnant, or are currently breastfeeding an infant.