The efficacy of particulate embolization combined with stereotactic radiosurgery for treatment of large arteriovenous malformations of the brain.

PURPOSE To evaluate the efficacy of combined particulate embolization and single-stage stereotactic radiosurgery in the treatment of large arteriovenous malformations (AVMs) of the brain. METHODS Twenty-four patients with large brain AVMs (diameter > 3.0 cm; volume > 14 cm3), who had previously undergone particulate embolization and stereotactic radiosurgery, were retrospectively evaluated 2 or more years after radiosurgery. RESULTS In 12 (50%) of these patients there was complete AVM obliteration, comparing favorably with a 58% obliteration rate in a group of AVMs having a 4- to 10-cm3 volume, treated by radiosurgery alone. Recanalization of embolized, but not radiated, AVM segments was identified in 3 (12%) patients. However, long-term occlusion was demonstrated in the embolized portions of most AVMs subsequently treated by radiosurgery. Complications included 1 (4%) patient with a mild upper extremity paresis after radiosurgery and 2 (8%) patients with transient neurologic deficits after embolization. CONCLUSION Combined embolization and stereotactic radiosurgery was more efficacious than radiosurgery alone for large brain AVMs. Recanalization after embolization did occur but was a relatively minor cause of treatment failure.