Stereotactic Radiosurgery for Intracranial Arteriovenous Malformations

Arteriovenous malformations (AVMs) in the brain, characterized by abnormal connections between arteries and veins without an intermediate capillary network, pose a significant risk of hemorrhagic stroke and neurological morbidity in young patients due to their congenital instability. Current treatment approaches for AVMs, including microsurgery, stereotactic radiosurgery (SRS), and embolization, aim to eliminate the risk of hemorrhage by eradicating the AVM nidus. SRS, a minimally invasive and effective treatment option, is well-suited for small- to medium-sized AVMs in deep or critical brain regions. Nidus obliteration is achieved in 70–80% of cases after an average latency period of 1–3 years post-treatment. However, SRS carries a unique set of complications, including a sustained risk of hemorrhage during the latency period and radiation-related adverse effects leading to neurological deficits. The suitability of AVMs for SRS varies based on their size, location, and rupture status, necessitating additional techniques such as endovascular embolization or volume and dose staging for larger AVMs to become appropriate targets for SRS. For unruptured AVMs, initial findings from recent prospective trials indicate that conservative medical management may yield better short-term outcomes compared to interventional treatments. Therefore, careful consideration must be given to the risks and complications associated with SRS therapy for individual AVMs, weighed against the morbidities associated with the natural progression of the disease. In this chapter, we comprehensively analyze the clinical and pathophysiological indications for SRS utilization, review data on treatment efficacy and outcomes, and profile the possible complications associated with this therapeutic approach.