From the Departments of Neuroradiology (N.S., F.S., M.B., M.A.M., D.F.V.).
Radiation Oncology (R.O.F., R.A.E.S.), Heidelberg University Hospital, Heidelberg, Germany.
AJNR Am J Neuroradiol. 2021 Jan;42(1):126-131. doi: 10.3174/ajnr.A6867. Epub 2020 Nov 19.
Endovascular embolization using liquid embolic agents is a safe and effective treatment option for AVMs and dural arteriovenous fistulas. The aim of this study was to assess the degree of artifact inducement by the most frequently used liquid embolic agents in conventional CT in an experimental in vitro model.
Dimethyl-sulfoxide-compatible tubes were filled with the following liquid embolic agents ( = 10, respectively): Onyx 18, all variants of Squid, PHIL 25%, PHIL LV, and -BCA mixed with iodized oil. After inserting the tubes into a CT imaging phantom, we acquired images. Artifacts were graded quantitatively by the use of Hounsfield units in a donut-shaped ROI using a customized software application that was specifically designed for this study and were graded qualitatively using a 5-point scale.
Quantitative and qualitative analyses revealed the most artifacts for Onyx 18 and the least artifacts for -BCA, PHIL 25%, and PHIL LV. Squid caused more artifacts compared with PHIL, both for the low-viscosity and for the extra-low-viscosity versions (eg, quantitative analysis, Squid 18: mean ± SD, 30.3 ± 9.7 HU versus PHIL 25%: mean ± SD, 10.6 ± 0.8 HU; < .001). Differences between the standard and low-density variants of Squid were observed only quantitatively for Squid 12. There were no statistical differences between the different concentrations of Squid and PHIL.
In this systematic in vitro analysis investigating the most commonly used liquid embolic agents, relevant differences in CT imaging artifacts could be demonstrated. Ethylene-vinyl alcohol-based liquid embolic agents induced more artifacts compared with liquid embolic agents that use iodine as a radiopaque component.
血管内栓塞使用液体栓塞剂是治疗动静脉畸形和硬脑膜动静脉瘘的安全有效方法。本研究旨在评估在常规 CT 中,最常使用的液体栓塞剂在体外实验模型中引起伪影的程度。
将二甲亚砜兼容的管分别填充以下液体栓塞剂(各 10 个管):Onyx 18、各种 Squid、PHIL 25%、PHIL LV 和混合有碘化油的 -BCA。将管插入 CT 成像体模后,我们采集图像。使用专门为此研究设计的定制软件应用程序,在环形感兴趣区域(ROI)中使用亨氏单位对伪影进行定量分级,并使用 5 分制进行定性分级。
定量和定性分析显示,Onyx 18 引起的伪影最多,-BCA、PHIL 25%和 PHIL LV 引起的伪影最少。与 PHIL 相比,Squid 引起的伪影更多,无论是低粘度还是超低粘度版本(例如,定量分析,Squid 18:平均值 ± 标准差,30.3 ± 9.7 HU 与 PHIL 25%:平均值 ± 标准差,10.6 ± 0.8 HU;<.001)。仅在 Squid 12 中观察到 Squid 的标准和低密度变体之间的定量差异。Squid 和 PHIL 的不同浓度之间没有统计学差异。
在这项系统性的体外分析中,研究了最常用的液体栓塞剂,证明了 CT 成像伪影方面的显著差异。基于乙烯-乙烯醇的液体栓塞剂引起的伪影比使用碘作为放射不透性成分的液体栓塞剂更多。