A Comprehensive Review of Radiosurgery for Cerebral Arteriovenous Malformations: Outcomes, Predictive Factors, and Grading Scales

Abstract

The management of cerebral arteriovenous malformations (AVMs) continues to present a challenge to neurosurgeons. The natural history of this condition, as well as the morbidity and mortality of therapeutic interventions, remains incompletely elucidated. Predictive factors and grading scales in AVM management allow risk-benefit analysis of treatment options and comparison of outcomes. Stereotactic radiosurgery is one of the established treatment modalities for AVMs and is generally used to treat lesions that are high risk for surgical resection. Radiosurgery aims to obliterate AVMs and thus prevent hemorrhage or seizure without any new or worsening of existing symptoms. Lesion characteristics and postsurgical complications differ markedly in patientstreated by radiosurgery versus microsurgery. Radiosurgery-based grading systems account for factors that have been associated with various aspects of radiosurgical outcomes including obliteration, hemorrhage, and postoperative complications, particularly those induced by radiation. The purpose of this paper is to describe the most current predictive factors and grading systems for radiosurgical treatment of cerebral AVMs.

Editorial. Management of incidental cerebral AVMs in the post-ARUBA era

“…Surgery in low-grade AVMs is very safe and offers the patient an immediate cure. 9,15,19,20 However, as demonstrated by the results of the current study, radiosurgery for unruptured AVMs can provide a relatively high chance of nidal obliteration with an acceptably low risk of symptomatic radiation adverse effects or postradiosurgical hemorrhage and may be a reasonable alternative, particularly in older patients or in patients with significant surgical comorbidities. Although a high rate of curative embolization with acceptable morbidity for Grade I and II has been reported, 18 in our opinion, embolization with an intention to cure should be reserved for select cases and performed only at institutions with significant experience in the technique.…”

“…4 In this study, the primary outcomes in those receiving treatment for SpetzlerMartin Grade I (14.3%), Grade II (43.3%), and Grade III (57.1%) lesions were unacceptably high. 8,9 Of the AVMs receiving a single treatment, 30 (46%) of 66 underwent embolization despite the relatively higher risks of embolization with a low potential for curative occlusion. The majority of hemorrhages occurred in patients who were initially treated with embolization and had incompletely obliterated AVMs.…”

A quantitative analysis of adverse radiation effects following Gamma Knife radiosurgery for arteriovenous malformations

“…Incidences are similar to those reported in the literature. 37 Through extensive follow-up, we have found that a significant number of patients with symptomatic radiation-induced changes will recover over time. 43 An appreciable ARE index value defined after univariate and multivariate analysis (Table 4) was defined as a minimum ARE index > 8.…”

Central Nervous System Vascular Malformations

“…The efficacy of AVM radiosurgery is much lower than with surgery (obliteration rates range from 36% to 92%, depending on the size of the lesion treated) [83,84]. Unlike surgery, obliteration is delayed by up to 3 years, and during this time the AVM is still at risk of rupture [85].…”