编织型辅助栓塞支架的血流导向作用及其在中小型(小于10mm)动脉瘤术后转归中的血流动力学机制研究

The flow diverter shows obvious advantage in treatment of large or giant aneurysms. However, there are several stents could be used when dealing with aneurysms less than 10mm. Therefore, in order to improve the outcome after treatment, it is a clinical problem to choose an optimal stent. The braid-assist stent is braided by metal wires. In addition to increasing the metal coverage, this type of stent is still designed to assist coil embolization treatment. Our previous results showed the efficacy of such stent was better than that of laser-cut stent. Therefore, we speculate that the different hemodynamics between the stents played an important role in the different results. However, we still lack the hemodynamic study of such stent and comparisons with other stent. Meanwhile, it is also limited in the studies of hemodynamic mechanisms in the outcome process of aneurysms after treatment using such stent. In addition, there is still no evidence that the pull-push technique in deployment of this braid-assist stent could improve the local flow diversion. This study intends to establish a prospective cohort, using advanced rapid virtual stenting technique to reconstruct the stent geometry and perform the flow dynamic simulations. To compare the abilities of flow diversion among different stents; then to explore hemodynamic mechanism of aneurysms outcome after endovascular treatment according to the results of angiographic follow-up; to evaluate and establish an effective outcome prediction system and outcome mechanism based stent selection method. To achieve precision medicine.

血流导向装置对大或巨大型动脉瘤疗效优势显著，但面对中小型（小于10mm）动脉瘤时，可选择支架较多，如何科学合理的选择支架以提高动脉瘤疗效是临床中的实际问题。编织型辅助栓塞支架采用网丝编织而成，在提高金属覆盖率的同时，仍采用辅助弹簧圈栓塞的治疗技术。本中心前期临床总结显示该支架治疗效果优于激光雕刻支架，因此我们推测支架间的不同血流导向能力可能在此差异中起显著作用。但是目前缺少其血流导向能力研究，以及与其他类型支架的对比分析，同时该类支架治疗术后转归的血流动力学机制尚不明确。另外，该编织型支架使用中的推拉释放技术是否能够提高局部血流导向作用仍缺乏流体力学证据。本研究拟建立前瞻性队列，采用先进的支架快速虚拟植入技术完成支架重建，并进行流体力学计算。对比分析该支架的血流导向能力；根据随访结果，阐明术后转归的血流动力学机制，建立有效的转归预测系统以及以预后机制为指导的支架选择使用方法，实现精准治疗。

颅内中小型动脉瘤介入治疗的支架选择有多种，合理选择支架以提高临床治疗效果是重要现实问题。编织型辅助栓塞支架金属覆盖率更高，但是其对转归的影响以及不同支架间的血流导向作用尚不明确。本研究主要分析明确编织型辅助栓塞支架的血流动力学作用，阐明不同释放技术以及不同支架类型间的血流导向差异。阐明编织型辅助栓塞支架治疗中小型颅内动脉瘤术后转归的血流动力学机制，建立以转归机制指导下的个体化支架选择方法。通过研究发现血流动力学在支架术后转归过程中起到重要作用，瘤颈平面的血流速度降低率是动脉瘤栓塞术后转归的关键因素，并且发现48.2%是其中的关键阈值；与PED相比，LVIS辅助弹簧圈栓塞在动脉瘤腔内产生了更大的血流动力学改变，并且LVIS密集释放相较常规释放具有更强血流导向作用，但是相较PED密网支架而言其血流导向作用稍差或者相当；LVIS辅助栓塞支架比Enterprise辅助栓塞支架具有更高的血流导向作用。研究结果揭示了中小型动脉瘤支架术后转归的机理，为临床中支架的选择使用以及预后转归的评估具有重要的指导意义。