Predicting the long-term success of endovascular interventions in the clinical management of cerebral aneurysms requires detailed insight into the patient-specific physiological conditions. In this work, we not only propose numerical representations of endovascular medical devices such as coils, flow diverters or Woven EndoBridge but also outline numerical models for the prediction of blood flow patterns in the aneurysm cavity right after a surgical intervention. Detailed knowledge about the post-surgical state then lays the basis to assess the chances of a stable occlusion of the aneurysm required for a long-term treatment success. To this end, we propose mathematical and mechanical models of endovascular medical devices made out of thin metal wires. These can then be used for fully resolved flow simulations of the post-surgical blood flow, which in this work will be performed by means of a Lattice Boltzmann method applied to the incompressible Navier-Stokes equations and patient-specific geometries. To probe the suitability of homogenized models, we also investigate poro-elastic models to represent such medical devices. In particular, we examine the validity of this modeling approach for flow diverter placement across the opening of the aneurysm cavity. For both approaches, physiologically meaningful boundary conditions are provided from reduced-order models of the vascular system. The present study demonstrates our capabilities to predict the post-surgical state and lays a solid foundation to tackle the prediction of thrombus formation and, thus, the aneurysm occlusion in a next step.

翻译：预测脑动脉瘤临床管理中血管内介入治疗的长期成功需要深入了解患者特定的生理条件。本文不仅提出了血管内医疗设备（如弹簧圈、血流导向装置或编织末端桥接器）的数值表示方法，还概述了预测术后即刻动脉瘤腔内血流模式的数值模型。对术后状态的详细了解为评估实现动脉瘤稳定闭塞（长期治疗成功所需）的可能性奠定了基础。为此，我们提出了由细金属丝制成的血管内医疗设备的数学和力学模型。这些模型可用于术后血流的高分辨率流动模拟——本研究采用格子玻尔兹曼方法，应用于不可压缩纳维-斯托克斯方程并结合患者特定几何结构进行求解。为检验均质化模型的适用性，我们还研究了用于表示此类医疗设备的多孔弹性模型，特别关注了该建模方法在动脉瘤开口处放置血流导向装置时的有效性。两种方法均通过血管系统的降阶模型提供具有生理意义的边界条件。本研究展示了预测术后状态的能力，并为下一步解决血栓形成及由此导致的动脉瘤闭塞预测问题奠定了坚实基础。