Ding Dale, Xu Zhiyuan, Yen Chun-Po, Starke Robert M, Sheehan Jason P
Department of Neurosurgery, University of Virginia, P.O. Box 800212, Charlottesville, VA, 22908, USA.
Acta Neurochir (Wien). 2015 Feb;157(2):281-91. doi: 10.1007/s00701-014-2305-4. Epub 2014 Dec 17.
Unruptured cerebral arteriovenous malformations (AVMs) in pediatric patients (age <18 years) were excluded from A Randomized Trial of Unruptured AVMs (ARUBA). Therefore, the efficacy of radiosurgery for unruptured pediatric AVMs is poorly understood. The goal of this study is to determine the outcomes and define the predictors of obliteration following radiosurgery for unruptured AVMs in pediatric patients.
We evaluated a prospective database, from 1989 to 2013, of AVM patients treated with radiosurgery at our institution. Patients with age less than 18 years at the time of radiosurgery, unruptured nidi, and at least 2 years of radiologic follow-up or AVM obliteration were selected for analysis. Statistical analyses were performed to determine actuarial obliteration rates and identify factors associated with obliteration.
In the 51 unruptured pediatric AVM patients included for analysis, the median age was 13 years, and the most common presentation was seizure in 53 %. The median nidus volume and radiosurgical margin dose were 3.2 cm(3) and 21.5 Gy, respectively. The median radiologic follow-up was 45 months. The actuarial AVM obliteration rates at 3, 5, and 10 years were 29 %, 54 %, and 72 %, respectively. In the multivariate Cox proportional hazards regression analysis, higher margin dose (P = 0.002), fewer draining veins (P = 0.038), and lower Virginia Radiosurgery AVM Scale (P = 0.003) were independent predictors of obliteration. Obliteration rates were significantly higher with a margin dose of at least 22 Gy (P = 0.003) and for nidi with 2 or fewer draining veins (P = 0.001). The incidences of radiologically evident, symptomatic, and permanent radiation-induced changes were 55 %, 16 %, and 2 %, respectively. The annual post-radiosurgery hemorrhage rate was 1.3 %, and the incidence of post-radiosurgery cyst formation was 2 %.
Radiosurgery affords a favorable risk to benefit profile for unruptured pediatric AVMs. Pediatric patients with unruptured AVMs merit further study to define an optimal management approach.
小儿患者（年龄<18岁）的未破裂脑动静脉畸形（AVM）被排除在未破裂AVM随机试验（ARUBA）之外。因此，对于小儿未破裂AVM的放射外科治疗效果了解甚少。本研究的目的是确定小儿未破裂AVM放射外科治疗后的结果，并确定闭塞的预测因素。
我们评估了1989年至2013年在我院接受放射外科治疗的AVM患者的前瞻性数据库。选择放射外科治疗时年龄小于18岁、巢未破裂且有至少2年影像学随访或AVM闭塞的患者进行分析。进行统计分析以确定精算闭塞率并识别与闭塞相关的因素。
纳入分析的51例小儿未破裂AVM患者中，中位年龄为13岁，最常见的表现为癫痫发作，占53%。巢的中位体积和放射外科边缘剂量分别为3.2 cm³和21.5 Gy。影像学随访的中位时间为45个月。3年、5年和10年的精算AVM闭塞率分别为29%、54%和72%。在多变量Cox比例风险回归分析中，较高的边缘剂量（P = 0.002）、较少的引流静脉（P = 0.038）和较低的弗吉尼亚放射外科AVM量表评分（P = 0.003）是闭塞的独立预测因素。边缘剂量至少为22 Gy时闭塞率显著更高（P = 0.003），引流静脉为2条或更少的巢闭塞率也显著更高（P = 0.001）。影像学明显改变、有症状改变和永久性放射诱发改变的发生率分别为55%、16%和2%。放射外科治疗后每年的出血率为1.3%，放射外科治疗后囊肿形成的发生率为2%。
放射外科治疗为小儿未破裂AVM提供了良好的风险效益比。小儿未破裂AVM患者值得进一步研究以确定最佳治疗方法。
