A 44-year-old man with seizures and a left parietal AVM. A, A 3 A 44-year-old man with seizures and a left parietal AVM.A, A 3.5-cm left parietal AVM with superficial and deep venous drainage (Spetzler and Martin grade IV).B, The AVM shows 80% obliteration with a single Onyx injection of 4.8 mL in 64 minutes.C, Onyx cas... A 44-year-old man with seizures and a left parietal AVM.A, A 3.5-cm left parietal AVM with superficial and deep venous drainage (Spetzler and Martin grade IV).B, The AVM shows 80% obliteration with a single Onyx injection of 4.8 mL in 64 minutes.C, Onyx cast after embolization.D, Complete obliteration of the AVM 2 years after gamma knife radiosurgery. W.J. van Rooij et al. AJNR Am J Neuroradiol 2007;28:172-177 ©2007 by American Society of Neuroradiology