 Endovascular treatment with platinum coils is safe and effective in preventing rebleeding of intracranial aneurysms. Unfortunately, endovascular treatment of aneurysms with coils has been associated with incomplete occlusion at initial treatment remnant or at follow-up recurrence. This in some studies has been as high as 20. While many such aneurysm remnants or recurrences exhibit benign behavior, many require retreatment to prevent future hemorrhage. 