Data_Sheet_1_Can Endovascular Treatment of Fusiform Intracranial Aneurysms Restore the Healthy Hemodynamic Environment?–A Virtual Pilot Study.PDF

Numerous studies assess intracranial aneurysm rupture risk based on morphological and hemodynamic parameter analysis in addition to clinical information such as aneurysm localization, age, and sex. However, intracranial aneurysms mostly occur with a saccular shape located either lateral to the parent artery or at a bifurcation. In contrast, fusiform intracranial aneurysms (FIAs), i.e., aneurysms with a non-saccular, dilated form, occur in approximately 3–13% of all cases and therefore have not yet been as thoroughly studied. To improve the understanding of FIA hemodynamics, this pilot study contains morphological analyses and image-based blood flow simulations in three patient-specific cases. For a precise and realistic comparison to the pre-pathological state, each dilation was manually removed and the time-dependent blood flow simulations were repeated. Additionally, a validated fast virtual stenting approach was applied to evaluate the effect of virtual endovascular flow-diverter deployment focusing on relevant hemodynamic quantities. For two of the three patients, post-interventional information was available and included in the analysis. The results of this numerical pilot study indicate that complex flow structures, i.e., helical flow phenomena and the presence of high oscillating flow features, predominantly occur in FIAs with morphologically differing appearances. Due to the investigation of the individual healthy states, the original flow environment could be restored which serves as a reference for the virtual treatment target. It was shown that the realistic deployment led to a considerable stabilization of the individual hemodynamics in all cases. Furthermore, a quantification of the stent-induced therapy effect became feasible for the treating physician. The results of the morphological and hemodynamic analyses in this pilot study show that virtual stenting can be used in FIAs to quantify the effect of the planned endovascular treatment.

大量研究基于形态学（morphological）、血流动力学（hemodynamic）参数分析，结合动脉瘤位置、年龄、性别等临床信息，评估颅内动脉瘤（intracranial aneurysm）的破裂风险。然而，颅内动脉瘤多为囊状形态，常位于载瘤动脉（parent artery）侧壁或分叉处。与之相对，梭形颅内动脉瘤（fusiform intracranial aneurysms, FIAs）——即非囊状扩张型动脉瘤——约占所有颅内动脉瘤病例的3%~13%，因此相关研究尚未得到充分开展。为加深对梭形颅内动脉瘤血流动力学的理解，本初步研究针对3例患者特异性病例开展了形态学分析与基于影像的血流模拟。为实现与病理前状态的精准且贴合实际的对比，研究人员手动移除了所有扩张区域，并重复开展了随时间变化的血流模拟。此外，本研究采用了一种经过验证的快速虚拟支架置入（virtual stenting）方法，以评估虚拟血管内血流转向装置（endovascular flow-diverter）置入的效果，重点关注相关血流动力学参数。3例患者中有2例提供了干预后信息，并将其纳入分析。本数值模拟初步研究的结果表明，复杂血流结构——即螺旋流（helical flow）现象与高振荡流（high oscillating flow）特征——主要出现在形态各异的梭形颅内动脉瘤中。通过对个体健康状态的分析，本研究还原了原始血流环境，可作为虚拟治疗目标的参考依据。研究表明，贴合实际的支架置入操作可使所有病例的个体血流动力学得到显著稳定。此外，临床医师可借此实现对支架介导治疗效果的量化评估。本初步研究的形态学与血流动力学分析结果表明，虚拟支架置入技术可应用于梭形颅内动脉瘤，以量化计划中的血管内治疗效果。