Importance Major neurological complications from the embolization of vein of Galen malformations (VOGMs) are poorly understood. We provide a detailed analysis of contributors to periprocedural neurological complications and lessons learned.

Objective To assess the rate of major periprocedural neurological complications following VOGM embolization with major procedural and strategic contributors.

Design, Setting, and Participants This retrospective cohort study was conducted at a quarternary referral pediatric hospital (Hospital for Sick Children; Toronto, Ontario, Canada) from January 1999 to December 2018 with a mean clinical follow-up of 44.7 months; all children with VOGM diagnosed and/or treated were eligible (n = 48). Thirty-three patients who underwent endovascular treatment were included.

Interventions Endovascular staged transarterial embolization performed in 33 patients over 91 sessions.

Main Outcomes and Measures The primary outcome was the rate of periprocedural neurological complications (occurring within 1 week of embolization). The secondary outcomes were mortality, long-term neurological outcomes, and contributing anatomical and management factors to neurological complications.

Results Of 33 patients who underwent embolization (31 boys [64.6%]; 17 girls [35.4%]; median age at first embolization, 4 months [range, 0-29 months]), 10 patients (30.3%) developed major periprocedural neurological complications. Five of these patients died. Univariate logistic regression analyses identified internal cerebral vein drainage to the main venous sac of the VOGM and use of a microcatheter with a distal outer diameter of more than 2.0F as significant predictors of poor neurological outcomes. Lessons learned from our experience include the need to assess the internal cerebral vein drainage pattern on preprocedural magnetic resonance venography, avoidance of excessive embolization into the venous sac, treatment of more distal fistulae before proximal fistulae to avoid a sump effect, and preferably use of smaller (<2.0F outer diameter) microcatheters in neonatal embolization procedures.

Conclusions and Relevance In this cohort, 10 patients with VOGM treated with embolization (30.3%) experienced major periprocedural neurological complications, half of whom died. While these outcomes are superior to historic conservative and surgical treatment results, ongoing improvements in treatment and pretreatment diagnostic approaches are needed. Awareness of the lessons learned from our experience can help to avoid similar complications in the future for this vulnerable population.

重要性 对Galen畸形（VOGM）静脉栓塞形成的主要神经系统并发症知之甚少。我们提供了围手术期神经系统并发症的贡献者的详细分析和经验教训。

目的 评估VOGM栓塞后主要的过程和策略贡献者的主要围手术期神经系统并发症的发生率。

设计，背景和参与者 这项回顾性队列研究于1999年1月至2018年12月在四分之一转诊儿科医院（病童医院；加拿大安大略省多伦多市）进行，平均临床随访时间为44.7个月。所有诊断和/或治疗过VOGM的儿童均符合条件（n = 48）。包括接受血管内治疗的33例患者。

干预 在91次疗程中对33例患者进行了血管内分期经动脉栓塞治疗。

主要结果和措施 主要结果是围手术期神经系统并发症的发生率（栓塞后1周内发生）。次要结局为死亡率，长期神经系统结局以及神经系统并发症的解剖学和管理因素。

结果 在33例接受栓塞术的患者中（31例男孩[64.6％]； 17例女孩[35.4％]；初次栓塞术的中位年龄为4个月[范围，0-29个月]），其中10例患者（30.3％）发生了严重的围手术期神经系统并发症。这些患者中有五人死亡。单因素逻辑回归分析确定了大脑内静脉向VOGM的主要静脉囊引流，并使用了远端外径大于2.0F的微导管作为不良神经系统预后的重要预测指标。从我们的经验中学到的经验教训包括需要评估术前磁共振静脉造影的脑内静脉引流方式，避免过多的栓塞入静脉囊，在近端瘘管之前治疗更多的远端瘘管以避免积液，最好使用较小的（<2。

结论与相关性 在该队列中，有10例经栓塞治疗的VOGM患者（30.3％）经历了严重的围手术期神经系统并发症，其中一半死亡。尽管这些结果优于历史上的保守和外科治疗结果，但仍需要不断改进治疗和治疗前诊断方法。意识到从我们的经验中学到的经验教训，可以帮助避免这种弱势群体今后发生类似的麻烦。