Intracraial aneurysm is the most common cause of subarachnoid hemorrhage.Its incidence varies in different areas,and overall,there is a growing tendency.The incidences and mortalities of ruptured and reruptured intracranial aneurysms remain high,and are influenced by various factors.With the development of diagnostic techniques,the prognosis of intracranial aneurysms is improving increasingly,and the mortality and morbidity have been gradually decreased.