Outcomes of Gamma Knife radiosurgery in pediatric arteriovenous malformations: the role of age and lesion characteristics

초록

Purpose The influence of age on radiosurgical outcomes in pediatric arteriovenous malformations (AVMs) remains unclear. This study evaluated the efficacy and safety of Gamma Knife radiosurgery (GKRS) across pediatric age subgroups. Methods We retrospectively analyzed pediatric patients (<= 18 years) who underwent GKRS for intracranial AVMs between 2000 and 2025. Patients were stratified into preadolescent (<= 12 years) and older pediatric (> 12 years) groups. Clinical, radiological, and treatment-related parameters were compared. Time-to-event analyses were performed to evaluate nidus obliteration and post-GKRS hemorrhage. Results The study included 136 patients who underwent 194 GKRS sessions. Fifty-seven patients (41.9%) were aged <= 12 years at the time of first GKRS. Baseline characteristics and treatment parameters were comparable between the age groups. During follow-up, complete nidus obliteration was achieved in 52 patients (38.2%), and post-GKRS hemorrhage occurred in 5 patients (3.7%). The estimated cumulative obliteration rates were 35.0% at 3 years and 41.8% at 5 years after GKRS. Age was not associated with nidus obliteration or post-GKRS hemorrhage in univariable or multivariable analyses. Higher prescription dose demonstrated a marginal independent association with nidus obliteration, whereas higher Spetzler-Martin grade showed a trend toward increased hemorrhage risk. Adverse radiation effects were rare and asymptomatic (2.9%). Repeat GKRS was performed in 31.6% of patients, primarily for persistent or residual AVMs identified during follow-up after the initial treatment. Conclusion Within the pediatric population, younger age was not associated with inferior radiosurgical outcomes. AVM complexity and treatment-related factors were the primary determinants of treatment outcome. GKRS can be applied safely and effectively across most pediatric age groups, and repeat radiosurgery represents a reasonable treatment strategy for selected complex lesions.

키워드