Embolization of cerebral arteriovenous malformations with Onyx: clinical experience in 44 cases

Objective:To evaluate the efficacy of Onyx(a new nonadhesive liquid embolic agent) embolotherapy for cerebral arteriovenous malformations(AVMs).Methods:15 cases of AVMs in frontoparitetal lobes,11 cases in parietooccipital lobes,9 cases in basal ganglia areas,5 cases in cerebellar hemispheres.The diameter of AVM masses in 14 cases were less than 3cm,3～6cm in 21 cases,larger than 6cm in 9 cases.6F sheath was inserted into femoral artery first,after 6F guiding catheter was introduced into the intracarotid artery or vertebral artery.Marathon microcatheter could be navigated into the nidus of AVMs,then the long time and slow injection of Onyx was taken to treat the AVM using the plug and push technique .Results:Effective embolization was achieved in all 44 cases,with complete embolization in 4cases,more than 80% embolization in 7 cases,50%～80% emboliazation in 21 cases,less than 50% embolization in 12 cases.Adhesion to the catheter happened in 1 cases,mild hemiparalysis happened in 2 cases,in which the hemiparalysis was markedly improved after administration of vasoactive medicine to enhance the microcirculation.Intracranial hemorrhage happened in 1 case,in which mild hemiparalysis remained after immediate hematoma removement by performance of craniotomy.No severe complications happened in other cases.Conclusion:Onyx has distinctive superiority in treating AVMs with its good adhesiveness and convenience control of the volume.However,the elaborative embolization techniques are involved to get better results and to avoid complications.