Mason J R, Dodge C, Benndorf G
1 Department of Radiology, Baylor College of Medicine, Houston, USA.
2 Texas Children's Hospital, Houston, USA.
Interv Neuroradiol. 2018 Oct;24(5):574-579. doi: 10.1177/1591019918773443. Epub 2018 May 19.
Background Endovascular treatment (EVT) of brain arteriovenous malformations has evolved from cyanoacrylate derivatives such as N-butyl cyanoacrylate, an adhesive glue, to ethylene vinyl copolymer-based liquid embolics such as Onyx® and SQUID® dissolved in dimethyl sulfoxide. Although these agents offer several advantages, their rapidly decreasing radiopacity, as a result of the sedimentation of tantalum powder, compromises visual control during EVT. This study aims to quantify and compare tantalum sedimentation rates of several liquid embolic agents, and determine their effects on radiopacity. Methods The rate of sedimentation of liquid embolics Onyx 18®, SQUID 12®, and SQUID 18® was measured after preparation by single x-ray exposures for a period of 30 minutes. The signal-to-noise ratios (SNRs) of the suspension of each liquid embolic was calculated at various time points as tantalum settled out of the suspension. Precipitating Hydrophobic Injectable Liquid (PHIL®) was imaged as a control. Results Onyx 18® demonstrated the fastest sedimentation rate of the liquid embolics analyzed and demonstrated a threefold faster drop in SNR compared to SQUID 18® over 30 minutes. Onyx 18® demonstrated a one and a half times faster drop in SNR compared to SQUID 12®. Although PHIL 25® maintained constant SNR over the same time, it was lower at baseline immediately after preparation compared to tantalum-based liquids. Conclusion Caution during long injections using tantalum-based agents is advised. Onyx 18® has a significantly faster drop in radiopacity compared to SQUID 12® and SQUID 18®. Covalently bonded iodine-based embolics like PHIL® demonstrate constant radiopacity over time.
背景 脑动静脉畸形的血管内治疗已从氰基丙烯酸酯衍生物（如作为粘合剂的N-丁基氰基丙烯酸酯）发展到基于乙烯-乙烯共聚物的液体栓塞剂，如溶解在二甲基亚砜中的Onyx®和SQUID®。尽管这些药物具有多种优势，但由于钽粉沉淀，它们的射线不透性迅速降低，这会影响血管内治疗期间的视觉控制。本研究旨在量化和比较几种液体栓塞剂的钽沉淀率，并确定它们对射线不透性的影响。方法 在制备后通过单次X射线照射30分钟来测量液体栓塞剂Onyx 18®、SQUID 12®和SQUID 18®的沉淀率。在钽从悬浮液中沉淀出来的不同时间点计算每种液体栓塞剂悬浮液的信噪比（SNR）。将沉淀型疏水可注射液体（PHIL®）成像作为对照。结果 Onyx 18®在分析的液体栓塞剂中显示出最快的沉淀率，并且在30分钟内其SNR下降速度比SQUID 18®快三倍。与SQUID 12®相比，Onyx 18®的SNR下降速度快1.5倍。尽管PHIL 25®在相同时间内保持SNR恒定，但与基于钽的液体相比，其在制备后立即的基线时较低。结论 建议在使用基于钽的药物进行长时间注射时要谨慎。与SQUID 12®和SQUID 18®相比，Onyx 18®的射线不透性下降明显更快。像PHIL®这样的共价键合碘基栓塞剂随时间显示出恒定的射线不透性。
