Object: The authors evaluated whether gamma knife radiosurgery (GKS) could be a causative factor in intratumoral bleeding in meningiomas.
Methods: Gamma knife radiosurgery was used in the treatment of 173 meningiomas during a 10-year period. Four patients suffered post-GKS intratumoral hemorrhage. The course in these patients was reviewed. Four of 173 patients suffered an intratumoral hemorrhage during a follow-up period of 1 to 8 years. The risk of intratumoral bleeding after GKS for meningioma was 2.3%. Intracystic hemorrhage occurred in two patients 1 and 5 years, respectively, after radiosurgery. In the other two cases intratumoral bleeding occurred 2 and 8 years, respectively, after radiosurgery. Histological examination in three cases found no specific findings related to the postradiosurgical changes.
Conclusions: Because the reported risk of spontaneous intratumoral bleeding in meningiomas is 1.3 to 2.7%, the incidence in this series was not unduly high. Radiosurgery itself could not be shown to be a significant factor in the development of the intratumoral bleeding.