未破裂脳動静脈奇形に対するradiosurgeryの適応決定に関する諸問題(<特集>未破裂脳動静脈奇形)  [in Japanese] Issues in Considering Indication of Radiosurgery for Unruptured Cerebral Arteriovenous Malformations(<Topics>Unruptured Arteriovenous Malformations)  [in Japanese]

We discuss several issues in considering indication of radiosurgery for unruptured cerebral arteriovenous malformations. The risk of hemorrhage until obliteration was reduced by 54% compared to that before radiosurgery. Hemorrhage risk was further reduced after obliteration, but a small risk of hemorrhage (12% of that before radiosurgery) remained, although the outcome of these patients was favorable. The risk of radiation-induced complications could be reduced with addition of MRI or CT in treatment planning. Further safety can be achieved by integrating tractography into treatment planning. The surgical resection of the nidus becomes easier after radiosurgery. The frequency of radiosurgery-induced malignancy may be comparable to that of surgical mortality. Patients generally tend to select less-invasive treatment. Nevertheless, long-term complications must be considered in treating patients with unruptured cerebral arteriovenous malformations.