Lee Cheng-Chia, Chen Ching-Jen, Ball Benjamin, Schlesinger David, Xu Zhiyuan, Yen Chun-Po, Sheehan Jason
Departments of 1 Neurological Surgery, and.
Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital; and.
J Neurosurg. 2015 Jul;123(1):126-35. doi: 10.3171/2014.12.JNS141437. Epub 2015 Feb 6.
Onyx, an ethylene-vinyl alcohol copolymer mixed in a dimethyl sulfoxide solvent, is currently one of the most widely used liquid materials for embolization of intracranial arteriovenous malformations (AVMs). The goal of this study was to define the risks and benefits of stereotactic radiosurgery (SRS) for patients who have previously undergone partial AVM embolization with Onyx.
Among a consecutive series of 199 patients who underwent SRS between January 2007 and December 2012 at the University of Virginia, 25 patients had Onyx embolization prior to SRS (the embolization group). To analyze the obliteration rates and complications, 50 patients who underwent SRS without prior embolization (the no-embolization group) were matched by propensity score method. The matched variables included age, sex, nidus volume before SRS, margin dose, Spetzler-Martin grade, Virginia Radiosurgery AVM Scale score, and median imaging follow-up period.
After Onyx embolization, 18 AVMs were reduced in size. Total obliteration was achieved in 6 cases (24%) at a median of 27.5 months after SRS. In the no-embolization group, total obliteration was achieved in 20 patients (40%) at a median of 22.4 months after SRS. Kaplan-Meier analysis demonstrated obliteration rates of 17.7% and 34.1% in the embolization group at 2 and 4 years, respectively. In the no-embolization group, the corresponding obliteration rates were 27.0% and 55.9%. The between-groups difference in obliteration rates after SRS did not achieve statistical significance. The difference in complications, including adverse radiation effects, hemorrhage episodes, seizure control, and patient mortality also did not reach statistical significance.
Onyx embolization can effectively reduce the size of many AVMs. This case-control study did not show any statistically significant difference in the rates of embolization or complications after SRS in patients who had previously undergone Onyx embolization and those who had not.
Onyx是一种混合于二甲基亚砜溶剂中的乙烯-乙烯醇共聚物，目前是颅内动静脉畸形（AVM）栓塞治疗中应用最广泛的液体材料之一。本研究的目的是明确对于先前接受过Onyx部分AVM栓塞治疗的患者，立体定向放射外科治疗（SRS）的风险和益处。
在弗吉尼亚大学2007年1月至2012年12月期间连续接受SRS治疗的199例患者中，25例在SRS之前接受过Onyx栓塞治疗（栓塞组）。为分析闭塞率和并发症，采用倾向评分法匹配50例未接受过栓塞治疗而接受SRS的患者（非栓塞组）。匹配变量包括年龄、性别、SRS前的病灶体积、边缘剂量、Spetzler-Martin分级、弗吉尼亚放射外科AVM量表评分以及影像学随访中位时间。
Onyx栓塞后，18个AVM体积缩小。SRS后中位27.5个月时，6例（24%）实现完全闭塞。在非栓塞组，SRS后中位22.4个月时，20例（40%）实现完全闭塞。Kaplan-Meier分析显示，栓塞组在2年和4年时的闭塞率分别为17.7%和34.1%。在非栓塞组，相应的闭塞率分别为27.0%和55.9%。SRS后两组间闭塞率差异无统计学意义。包括放疗不良反应、出血事件、癫痫控制和患者死亡率在内的并发症差异也未达到统计学意义。
Onyx栓塞可有效缩小许多AVM的体积。本病例对照研究未显示先前接受过Onyx栓塞治疗的患者与未接受过该治疗的患者在SRS后的栓塞率或并发症发生率上有任何统计学显著差异。
