Abstract:
Intracranial aneurysms (IAs) pose severe health risks influenced by hemodynamics. This study focuses on the intricate characterization of hemodynamic conditions within the IA walls and their influence on bleb development, aiming to enhance understanding of aneurysm stability and the risk of rupture. The methods emphasized utilizing a comprehensive dataset of 359 IAs and 213 IA blebs from 268 patients to reconstruct patient-specific vascular models, analyzing blood flow using finite element methods to solve the unsteady Navier-Stokes equations, the segmentation of aneurysm wall subregions and the hemodynamic metrics wall shear stress (WSS), its metrics, and the critical points in WSS fields were computed and analyzed across different aneurysm subregions defined by saccular, streamwise, and topographical divisions. The results revealed significant variations in these metrics, correlating distinct hemodynamic environments with wall features on the aneurysm walls, such as bleb formation. Critical findings indicated that regions with low WSS and high OSI, particularly in the body and central regions of aneurysms, are prone to conditions that promote bleb formation. Conversely, areas exposed to high WSS and positive divergence, like the aneurysm neck, inflow, and outflow regions, exhibited a different but substantial risk profile for bleb development, influenced by flow impingements and convergences. These insights highlight the complexity of aneurysm behavior, suggesting that both high and low-shear environments can contribute to aneurysm pathology through distinct mechanisms.
摘要:
颅内动脉瘤(IAs)在血流动力学的影响下构成严重的健康风险。本研究集中于IA壁内血液动力学状况的复杂表征及其对气泡发育的影响。旨在提高对动脉瘤稳定性和破裂风险的认识。该方法强调利用来自268名患者的359个IA和213个IA气泡的综合数据集来重建患者特定的血管模型。使用有限元方法分析血流来求解非定常Navier-Stokes方程,动脉瘤壁子区域的分割和血流动力学指标壁切应力(WSS),它的指标,WSS场中的临界点被计算和分析在不同的动脉瘤子区域定义,流向,和地形分区。结果显示,这些指标存在显著差异,将不同的血液动力学环境与动脉瘤壁上的壁特征相关联,如气泡形成。关键研究结果表明,WSS低和OSI高的地区,特别是在动脉瘤的身体和中心区域,容易出现促进气泡形成的条件。相反,暴露于高WSS和正发散的区域,像动脉瘤的颈部,流入,和外流地区,表现出不同但实质性的气泡发展风险,受流量冲击和趋同的影响。这些见解突出了动脉瘤行为的复杂性,这表明高剪切和低剪切环境都可以通过不同的机制导致动脉瘤病理。