Berns Holly, Robertson Sophia, Lewis Kailey, Wells Jesse, Clark Wyatt, Becker Timothy A
Mechanical Engineering Department, Northern Arizona University, Flagstaff, Arizona, USA.
Bioengineering Program, Northern Arizona University, Flagstaff, Arizona, USA.
J Neurointerv Surg. 2025 Jun 1;17(e2):e388-e392. doi: 10.1136/jnis-2024-021743.
Ischemic stroke is a leading cause of death and significant long-term disability worldwide. Mechanical thrombectomy is emerging as a standard treatment for eligible patients. As clinical implementation of stent retrieval and aspiration thrombectomy increases, there is a need for physiologically relevant in vitro device efficacy testing. Critical to this testing is the development of standardized 'soft' and 'hard' synthetic blood clots that mimic the properties of human thrombi and are compatible with imaging technologies. Synthetic clots allow researchers to extract information regarding clot integration, model hemodynamics, and quantify the physics of thrombectomy.
This work develops polyacrylamide and alginate-based synthetic clots that are compatible with particle image velocimetry (PIV) and radiographic imaging techniques while maintaining mechanical properties of 'soft' and 'hard' human clots. Dynamic mechanical analysis testing using an HR2-Rheometer demonstrates comparable mechanical properties to human clots previously tested by this research group and provided in existing literature.
The synthetic clots are formulated with either 0.5% w/v polyethylene microspheres for PIV visualization or 20% w/v barium sulfate for angiographic visualization, enabling real-time imaging of clot behavior during thrombectomy simulations. The soft formulation shows compressive and shear properties of ~12 kPa and 2-3 kPa, respectively. The hard clots are 3-4 times stiffer, with compressive and shear properties of 41-42 kPa and 8-9 kPa, respectively.
Standardized synthetic clots offer a platform for reproducible device testing. This provides a greater understanding of mechanical thrombectomy device efficacy, which may lead to quantifiable advances in device development and eventual improved clinical outcomes.
缺血性中风是全球范围内导致死亡和严重长期残疾的主要原因。机械取栓术正逐渐成为符合条件患者的标准治疗方法。随着支架取栓和抽吸血栓切除术在临床中的应用增加，需要进行与生理相关的体外设备疗效测试。这种测试的关键是开发标准化的“软”和“硬”合成血凝块，它们能够模拟人类血栓的特性并与成像技术兼容。合成血凝块使研究人员能够提取有关血凝块整合的信息、模拟血流动力学并量化取栓术的物理过程。
这项工作开发了基于聚丙烯酰胺和藻酸盐的合成血凝块，它们与粒子图像测速技术（PIV）和放射成像技术兼容，同时保持“软”和“硬”人类血凝块的机械性能。使用HR2流变仪进行的动态力学分析测试表明，其机械性能与该研究小组先前测试并在现有文献中提供的人类血凝块相当。
合成血凝块分别用0.5%（w/v）的聚乙烯微球进行PIV可视化或用2-%（w/v）的硫酸钡进行血管造影可视化，从而能够在取栓术模拟过程中对血凝块行为进行实时成像。软质配方的压缩和剪切性能分别约为12 kPa和2-3 kPa。硬质血凝块的硬度是其3-4倍，压缩和剪切性能分别为41-42 kPa和8-9 kPa。
标准化的合成血凝块为可重复的设备测试提供了一个平台。这有助于更深入地了解机械取栓设备的疗效，可能会在设备开发方面取得可量化的进展，并最终改善临床结果。
