Use of Onyx (a patented ethylene-vinyl alcohol copolymer formulation) embolisation of cerebral arteriovenous malformations in Hong Kong: initial experience.

OBJECTIVE To review the experience with Onyx embolisation of cerebral arteriovenous malformation. DESIGN Prospective study. SETTING A regional neurosurgical centre in Hong Kong. PATIENTS Data of patients with cerebral arteriovenous malformation who underwent Onyx embolisation over a 14-month period were prospectively collected. RESULTS Eleven sessions of Onyx embolisation were performed in nine patients with cerebral arteriovenous malformations, seven of which had ruptured. Total occlusion was achieved in three (33%) of the patients, and subtotal occlusion (over 80% occlusion) in three out of four with Spetzler-Martin grade-III/IV malformations. One patient developed mild permanent neurological deficit. CONCLUSION Onyx embolisation of cerebral arteriovenous malformations is feasible in Hong Kong. Careful patient and target selection are important.