Business decision to focus on other studies. No safety concern.

The primary objective of this study is to gather data on the radiation exposure in patients treated with the Penumbra Coil 400™ System (PC 400) or conventional coils per their respective indications for use.This is a multicenter case review study of patients presenting with intracranial aneurysms who are treated with coil embolization therapy using the PC 400 or conventional coils. Data for each patient are collected acutely.Up to 90 patients treated with the PC 400 or conventional coils (2:1) at up to 15 centers in the USA will be enrolled.

Inclusion Criteria:

• Patients enrolled in the PC 400 arm must be those treated according to the cleared indication for the PC 400 System, which includes endovascular embolization of intracranial aneurysms.
• Patients treated with conventional coils should be treated per their IFU.
• Adjunctive use of stents, balloons or liquid embolics, if considered appropriate by investigators, is allowed.

Exclusion Criteria:

• Pre-planned use of multiple coil systems and/or flow diverters.

Up to 90 patients treated with the PC 400 or conventional coils (2:1) at up to 15 centers in the USA will be enrolled.