Gamma Knife treatment strategies for paediatric AVMs: approaches to refractory cases

Introduction:While paediatric arteriovenous malformations (AVMs) often require aggressive therapeutic intervention due to their high bleeding incidence, choosing a course of treatment for deep and eloquent areas and asymptomatic cases is difficult. Sequelae are a concern in children, as they survive for longer after treatment. The authors have long recommended and implemented staged Gamma Knife radiosurgery (GKRS) in their treatment guidelines to maximise therapeutic effects.Methods:Fifty-eight paediatric patients with AVM and <= 15 years old who underwent GKRS under general anesthesia from 2002 to 2020 were followed up for an average of 81 center dot 5 months. Obliteration dynamics and clinical outcomes were analysed.Results:The mean patient age was 10 center dot 5 years. The mean nidus volume was 6 center dot 6 cm3, the complete occlusion rate was 69%, the annual post-irradiation bleeding rate was 2 center dot 19% and nine (16%) cases had transient radiation-induced changes. One (1 center dot 7%) patient had sequela, and three (5 center dot 1%) developed encapsulated hematomas and cysts. Additionally, the 3- and 5-year cumulative occlusion rates were 39 center dot 0% and 53 center dot 3%, respectively. Multivariate analysis showed significantly higher occlusion rates in patients <= 12 years old and with a nidus volume of <= 4 cm3.Conclusions:GKRS is a useful treatment for paediatric AVM; however, its use poses some challenges.