Pilot Study of the Contour Neurovascular SystemTM

Inclusion Criteria: 1. Age 18-80 years at screening 2. Unruptured saccular IA in the anterior or posterior circulation with dimensions consistent with Table 2 3. IA appears suitable for Contour Neurovascular SystemTM device Patient has the necessary mental capacity to participate and is willing and able to participate in the study for the duration of the study follow-up and is able to comply with study requirements Patient able to understand and sign a study-specific informed consent form Exclusion Criteria: 1. Ruptured IA 2. Any other IA that requires treatment in the next year 3. IA width \>8.5 or \<2 mm 4. IA neck \>8 or \<2 mm 5. IA minimum height \<4mm 6. IA embolisation would most likely cause stroke 7. Target IA contains other devices/implants (e.g., coils) 8. Inability to access the target IA with the microcatheter 9. Any congenital or iatrogenic coagulopathy 10. Platelet count \<50,000/microliter 11. Known allergy to platinum, nickel or titanium 12. Known allergy to contrast agents 13. Stenosis of the target IA's parent vessel \>50% 14. Taking daily aspirin or other platelet inhibitor (clopidogrel or equivalent) other than for the target aneurysm 15. Taking any anticoagulants (e.g., warfarin) 16. Abnormal clotting parameters 17. Pregnant, breastfeeding or planning pregnancy in the next 2 years 18. Other medical conditions that could increase the risk of neurovascular procedures (e.g., liver failure, cancer, etc.) or ability to comply with study requirements Participating in another study with investigational devices or drugs