Nidal embolization of brain arteriovenous malformations using Onyx in 94 patients.

BACKGROUND AND PURPOSE To report our experience in the treatment of brain arteriovenous malformations (BAVMs) using Onyx (ev3, Irvine, Calif). PATIENTS AND METHODS From January 1999 to October 2004, 94 patients with BAVMs were treated endovascularly in our department. They were 51 (54%) men and 43 (46%) women with a mean age of 32 years. A total of 210 endovascular procedures were performed with Onyx as the sole embolic agent in 88 procedures; Onyx and n-butyl cyanoacrylate (n-BCA) were used in combination in 50 procedures, and n-BCA alone was used in 72 procedures. RESULTS The course of endovascular treatment was completed in 53 patients. In 26 patients (49%, 26/53) an angiographic cure was achieved using embolization as the sole therapeutic technique. Seven (13%, 7/53) patients underwent a surgical resection of the residual BAVM nidus, 20 (38%, 20/53) patients underwent radiosurgical treatment after nidal size reduction <2 cm was accomplished by endovascular treatment. Further endovascular treatment was planned in 33 patients, whereas in 5 patients, the continuation of embolization was aborted due to difficult nidus catheterization. Procedure-related permanent neurologic deficits were observed in 8 (8.5%, 8/94) patients. There were 3 procedure-related deaths. CONCLUSION Onyx is suitable for brain BAVM embolizations and allows obtaining higher rates of anatomic cures compared with those obtained previously with other embolic agents.