Role of endovascular embolization in treatment of cerebral arteriovenous malformations

AIM To evaluate the significance of endovascular embolization in treatment of cerebral arteriovenous malformations. METHODS From March 1997 to March 2001, 148 patients with AVM were treated by endovascular embolization. Of all the patients, microsurgical resection was performed in 87 patients after endovascular embolization. 9 patients were suggested to undergo radiation of radiosurgery. According to Spetzler and Martin grading scale, 18 patients were Grade Ⅰ, 20 as Grade Ⅱ, 21 as Grade Ⅲ, 50 as Grade Ⅳ, 35 as Grade Ⅴ, and 4 as Grade Ⅵ. Therapeutic methods included endovascular embolization, post embolization surgery and post embolization radiation of г knife or X knife. RESULTS Endovascular embolization were performed in all 148 patients with AVM. After embolization, 100% occlusion were obtained in 33 patients (22.3%), obliteration rate more than 75% of AVM nidus in 66 (44.6%), 50~70% of AVM nidus were obliterated in 26 (17.6%), obliteration rate less than 50% of AVM nidus in 23 (15.5%). 4 patients exhibited a new persistent neurological deficit after embolization (2.7%). Microsurgery was performed in 87 patients following embolization. Lesion were totally removed in 82 patients (94%). Subtotal or incomplete removal were achieved in 5(6%). Post operative complication rate was 4.6% (4 cases). Follow up angiogram was taken in 3 of 9 patients who underwent radiosurgery 2 years after radiation. The results showed that the lesion had been completely occluded. No radiation related complication occurred. CONCLUSION Multimodal treatment including microsurgery, endovascular embolization and radiosurgery is a safe and effective method for cerebral AVM. Part of AVM patients can be cured by embolization alone, furthermore most of the AVM nidus can be reduced to a size suitable for surgical resection and radiosurgery with high success rate and low complication.