[Management of aneurysmal subarachnoid hemorrhage]

The annual incidence of aneurysmal subarachnoid hemorrhage (SAH) is approximately 20 per 100,000/ year in Japan, and it is suggested that approximately 40% of SAH patients have poor outcome. Rebleeding after SAH and delayed cerebral vasospasm are the most important causes of poor outcomes. Particularly, rebleeding significantly worsened the outcome, therefore, its prevention is of utmost importance. Preventive measures against rebleeding include open surgery and endovascular treatment without craniotomy. Selection of the measures to prevent rebleeding should be based on neurological assessment, location and shape of cerebral aneurysm, anticipated difficulties in the treatment, presence of complications, etc. At present, surgical clipping remains the method of choice in Japan. However, there has been growing acceptance that the efficacy of endovascular treatment is comparable to that of surgical treatment, suggesting endovascular treatment should be considered in suitable patients with ruptured cerebral aneurysms. In this report, we describe the proceedures for the standard management of SAH, in particular, treatment of ruptured cerebral aneurysm and selection of treatment measures, according to the Japanese guidelines for the management of aneurysmal subarachnoid hemorrhage.