The Efficacy of Gamma Knife Radiosurgery for Cavernous Malformations: A Meta-Analysis and Review

OBJECTIVE: This meta-analysis is to evaluate the clinical efficacy of gamma knife radiosurgery (GKRS) for treating cavernous malformations. METHODS: PubMed, Ovid Embase, and Ovid Medline electronic databases were searched. The primary outcome is hemorrhage rate and this meta-analysis is performed. RESULTS: Nine studies are included in this meta-analysis. The overall risk ratio (RR) of hemorrhage rate of pre-GKRS and post-GKRS is 6.08 (95% confidence interval [CI], 5.04-7.35). The overall RR is 3.03 (95% CI, 2.65-4.11) between the hemorrhage rate of pre-GKRS and the first 2 years postradiosurgery, and the overall RR is 12.13 (95% CI, 1.73-85.07) comparing pre-GKRS with 2 years after GKRS. There is no significant difference of the hemorrhage rate between the first 2 years postradiosurgery and 2 years after GKRS (RR [2.81; 95% CI, 0.20-13.42). The neurologic deficiency is the most common radiosurgery-related complication. CONCLUSIONS: Patients with cerebral cavernous malformations, especially ones that were deep seated and surgically inaccessible, seem to benefit from GKRS owing to a reduction of annual hemorrhage rate in the first 2 years and 2 years after, despite several cases that suffer from negative side effects of radiation.