Analysis on the effect and prognostic factors of cerebral arteriovenous malformations (AVM) after endovascular embolization combined gamma knife surgery

Background: Brain Arteriovenous Malformation (BAVM) was induced by the congenital development abnormality of partial vascular anomaly differentiation. Better prognostic factors should be developed by our researchers. Objective: To analyse the clinical and follow-up materials about Arteriovenous Malformation (AVM) treated by endovascular embolization combined with radiosurgery (Gamma Knife Surgery, GKS), and discuss the efficacy and influencing factors of AVM treatment, thus providing a reference for the clinical treatment of AVM. Methods: A summary for 55 cases of AVM patients having received the endovascular embolization combined with GKS in the Department of Interventional Neuroradiology, Beijing Tiantan Hospital from April 2004 to September 2011 and having rather complete follow-up materials is carried out, and a statistical analysis is conducted for the focus volume size, Spetzler Martin grade, impact characteristics of malformation vascular mass, and the influence of radiation dose and other variables on patients’ treatment efficacy. Results: The complete cure rate of patients after combined treatment in this research is 31.25%. The mean volume before embolism is 16.68 ± 16.22 cm3 (range: 0.75-75 cm3). Among 17 AVM patients whose initial symptom is epilepsy, 8 have clearly reduced the epileptic seizure frequency or become completely recovered after GKS. Among the 37 patients with image follow-up, the overall cure rate is 31.25%. The risk factor prediction of bleeding complications after endovascular embolization combined with GKS is of statistical significance: The AVM volume (P=0.039), the number of supply artery (P=0.048), and the draining vein phlebostenosis (P=0.01). The long-term prognosis influencing factors of endovascular embolization combined with GKS were: mRS prior to admission (p=0.011), follow-up time (p=0.013). Conclusion: Endovascular embolization combined with GKS is a safe and effective method for AVM, but it cannot completely eliminate embolism malformation mass, so the risk of rupture haemorrhage still exists.