Gamma Knife Radiosurgery of Brainstem Cavernous Malformations

Abstract

Background/aims: Our study aimed to evaluate the efficiency and morbidity of Gamma Knife radiosurgery (GKS) in the treatment of hemorrhagic brainstem cavernous malformations (CMs).

Methods: We included in this study all patients who underwent GKS for the treatment of a hemorrhagic brainstem CM(s) in our institution between January 2007 and December 2012. The GKS was privileged when the surgical procedure was evaluated as very risky. The mean dose of radiation was 14.8 Gy, and the mean target volume was 0.282 cm3. All patients participated in a scheduled clinical follow-up. The posttreatment MRI was performed after 6 months and after 1 year, and then all patients had an annual MRI follow-up.

Results: There were 19 patients with a mean age of 36.7 years. The mean follow-up period was 51.2 months. The annual hemorrhage rate (AHR) was 27.31% before GKS, 2.46% during the first 2 years following the GKS, and 2.46% after the first 2 years following the GKS. The decrease in AHR after GKS was significant (p < 0.001).

Conclusion: GKS should be suggested when the surgical procedure harbors a high risk of neurological morbidity in patients with brainstem CM. Compared to prior literature results, a lower dose than applied in this study could be discussed.