Aneurysmal subarachnoid haemorrhage (SAH) is a very serious neurosurgical problem, associated with high rates of morbidity and mortality. After the initial haemorrhage, up to 50% of the patients die, and 30-40% of the patients suffer a new bleeding during the first month. The percentage of deaths due to a new bleeding is between 60% and 75%. Both endovascular embolization and surgery treatments reduce the mortality rate and improve the quality of life of the survivors. In recent years, endovascular embolization has become the method of choice to prevent new bleeding, especially in Europe,...