Our treatment strategy of cerebral arteriovenous malformation: safer radiosurgery combined endovascular surgeryOsamu Nagano1, Toru Serizawa2, Shushi Kominami3, Yoshinori Higuchi1, Shinji Matsuda4, Kyoko Aoyagi4, Toshio Machida5, Shiro Kobayashi3, Junichi Ono5, Naokatsu Saeki61Chiba, Japan 2Tokyo, Japan 3Department of Neurosurgery, Chiba-Hokuso Hospital, Nippon Medical School, Chiba, 4Gamma Knife House, Chiba Cardiovascular Center, Ichihara, Japan 5Department of Neurosurgery, Chiba Cardiovascular Center, Ichihara, Japan 6Department of Neurological Surgery, Chiba University, Chiba, Japan Keywords: arteriovenous malformation, embolization, gamma knife, outcome, radiosurgery
Multi-modality approaches can benefit patients with arteriovenous malformations of the brain.
We analyzed to define the benefits and risks of gamma knife radiosurgery (GKS) for arteriovenous malformation (AVMs) patients who underwent prior embolization.
In this study, 126 patients (63%) had at least one prior hemorrhage in group A and 63 patients (63%) included in group B.
Between 1999 and 2011, we performed GKS on 300 patients with cerebral AVMs (nidus volume less than 10.0 cm3); 100 patients underwent embolization prior to GKS (group A), 200 patients without embolization (group B). We evaluated obliteration rate, latency interval hemorrhage and symptomatic delayed radiation injury (DRI) compared between 2 groups using Kaplan-Meier method. Our treatment policy is that embolization prior to GKS is necessary for large volume AVM (more than 10.0 cm3), high-flow AVM and intranidul aneurysm in order to reduce the risk of AVM bleeding during latency period and DRI.
The median target volume was 3.1 cm3 (range 0.05 to 9.2) in group A and 1.7 cm3 (range 0.08 to 9.6) in group B. The median peripheral dose was 19 Gy in group A and 20 Gy in group B. The actuarial obliteration rates on angiography at 4 years were 90% in group A and 87% in group B (p=0.37). Latency interval hemorrhage developed in 1 case at group A (cumulative risk was 1.1% at 10 years) and 8 cases at group B (6.9% at 10 years) (p=0.24). Symptomatic DRI was observed 2 cases in group A (cumulative risk was 7.0% at 10 years), 7 cases in group B (4.2% at 10 years) (p=0.89).
This was a retrospective study.
Our study demonstrated that prior embolization did not change the obliteration rate while it may reduce the risk of AVM bleeding and DRI after GKS.
Combined AVM strategies require further evaluation of hemorrhage, safety, and obliteration outcomes. Project Roles:
O. Nagano (), T. Serizawa (), S. Kominami (), Y. Higuchi (), S. Matsuda (), K. Aoyagi (), T. Machida (), S. Kobayashi (), J. Ono (), N. Saeki ()