Embolization with detachable coils is a safe and effective treatment of brain aneurysms. The 1-year results of the ISAT Study [29] of endovascular coiling of aneurysms (considered suitable for both neurosurgical clipping and endovascular coiling) yielded a significant advantage over neurosurgical clipping in terms of death and severe disability. Of patients allocated to endovascular treatment, 250 of 1063 (23.5%) were dead or dependent at 1 year compared with 326 of 1055 (30.9%) patients allocated to neurosurgical clipping. As such, the absolute risk reduction was calculated as 7.4% (95% CI: 3.6-11.2; P = .0001) in favor of endovascular treatment. Because of this significant difference between coiling and clipping, treatment of patients with a ruptured intracranial aneurysm changed significantly over the past years, particularly in Europe. In many centers, coiling has become the method of choice when both coiling and clipping are considered suitable in the individual patient.