Cerebral arteriovenous malformations: Issues of the interplay between stereotactic radiosurgery and endovascular surgical therapy

Intracranial arteriovenous malformations (AVMs) are congenital lesions frequently diagnosed as a result of hemorrhage or other neurological symptoms. Prevention of such devastating neurological injury has promoted a variety of treatment strategies. The rich history of multimodal therapy in the treatment of AVMs includes microsurgery, endovascular embolization, and stereotactic radiosurgery (SRS). This article reviews the biology and natural history of AVMs, as well as their treatment with both SRS and endovascular neurosurgery. It considers various paradigms and goals of endovascular treatment, along with relevant issues such as the features of an AVM to be targeted. Issues of the interplay between SRS and endovascular neurosurgery include the compartments of an embolized AVM to contain within the radiosurgery plan, the radioprotective and radiosensitizing effects of the embolic agent, the durability of embolization, and the sequencing of embolization with respect to the radiosurgical treatment. Published literature on these topics is sparse, and the flimsiness of the data offers limited guidance.