Predictive factors of epilepsy in arteriovenous malformation.

OBJECTIVE: Structural epilepsy related to cerebral arteriovenous malformation (AVM) suggests different epileptogenic mechanisms. The aim of our study was to determine factors associated with epilepsy into a retrospective cohort of AVM patients. PATIENTS AND METHODS: Ruptured and unruptured AVM data retrieved from a prospective single center registry (2009-2016) were retrospectively assessed. Demographic, clinical and radiological features were identified in AVM patients with or without epilepsy according to the International League Against Epilepsy classification. RESULTS: Epilepsy concerned 22 out of 80 consecutive patients with AVM (27.5%). Univariate analysis comparing both groups revealed a significant association of different variables with the structural epilepsy: young age (P=0.02), large nidus size (P=0.02), venous dilation (P=0.02), posterior cerebral artery (PCA) feeder (P<0.001) and Spetzler-Martin grade (P=0.02). Based on multivariate analysis, only the PCA feeder was identified (OR=5.2 [95% CI 1.1-24,5], P=0.04). CONCLUSION: PCA feeder for cerebral AVM was significantly associated with structural epilepsy. The hypothesis of a vascular steal phenomenon to the detriment of internal temporal lobe vascularization could be related to the development of epilepsy.