Embolization of Cerebral Arteriovenous Malformations with A New Liquid Embolic Agent (Onyx): Clinical Experience in 28 cases

Objective To report the embolization techniques and efficacy of cerebral arteriovenous malformations(AVMs) using a new liquid embolic agent (Onyx). Methods 18 cases of cerebral AVMs were located in functional area, 8 cases in deep cerebral area, and 2 cases in cerebellar hemisphere. The diameter of AVMs was about 3 cm in 11 cases, 3～6 cm in 12 cases, and larger than 6cm in 5 cases. 6F sheath was inserted into femoral artery first, after 6F guiding catheter was introduced into the intracarotid artery or vertebral artery, Ultraflow microcatheter could be navigated into the nidus of AVMs, then the long time and slow injection of Onyx-18 was taken to treat the cerebral AVM using the “plug and push technique”. Results 20%～100% embolization was achieved in all cases, 40% on average in early stage, and nearly 80% at present. 4 AVMs were considered to be totally occluded with Onyx in this group. Mild to severe hemiparalysis happened in 3 cases and visual field defect in one case after embolization, no severe complications in other 24 patients. Conclusions Onyx has unique and distinctive superiority in treating cerebral AVMs. However, the embolization techniques should be learned to get good results and to avoid complications. The long-term efficacy of Onyx embolization needs to be followed up.