Stereotactic Radiosurgery for Pediatric High-Grade Brain Arteriovenous Malformations: Our Experience and Review of Literature.

Abstract

Although high-grade AVMs pose a particularly high lifetime hemorrhage risk to pediatric patients (age <18 years), little is known about the treatment outcomes. Therefore, the aim of this retrospective cohort study was to evaluate the outcomes after single-session stereotactic radiosurgery (SRS) for pediatric high-grade AVMs. We reviewed baseline and treatment outcomes data from pediatric patients aged less than 18 years with Spetzler-Martin grade IV AVMs treated with SRS in a single session at our institution. The study cohort comprised 28 pediatric patients with Spetzler-Martin grade IV AVMs, with a mean age of 12.1 years. Statistical analyses were performed to determine predictors of obliteration and compare the outcomes of patients with versus without previous AVM hemorrhage. The mean nidus volume, radiosurgical margin dose, and follow-up duration were 5.9 cm3, 19.4 Gy, and 116 months, respectively. The actuarial obliteration rates at 3, 5, 7, and 10 years were 11%, 19%, 29%, and 35%, respectively. Older age was significantly associated with obliteration in the univariate Cox proportional regression analysis (P= 0.01). During the latency period before obliteration, the annual post-SRS hemorrhage rate was 3.2%. Symptomatic and permanent radiation-induced changes were detected in 7.1% and 3.5%, respectively. Afavorable outcome was achieved in 35.7%, and it was more frequently achieved for those with ruptured AVMs (P= 0.0484). The efficacy of single-session SRS for the treatment of high-grade AVMs in the pediatric population is limited, particularly for those with unruptured nidi. Multimodal therapies should be considered in the management of selected pediatric high-grade AVMs. However, further prospective analyses are warranted to define the optimal management strategy for these challenging vascular malformations.