Department of Bioengineering, George Mason University, Fairfax, Virginia, USA.
Department of Neurosurgery, Allegheny General Hospital, Pittsburgh, Pennsylvania, USA.
Int J Numer Method Biomed Eng. 2024 Aug;40(8):e3837. doi: 10.1002/cnm.3837. Epub 2024 Jun 5.
The mechanisms behind intracranial aneurysm formation and rupture are not fully understood, with factors such as location, patient demographics, and hemodynamics playing a role. Additionally, the significance of anatomical features like blebs in ruptures is debated. This highlights the necessity for comprehensive research that combines patient-specific risk factors with a detailed analysis of local hemodynamic characteristics at bleb and rupture sites. Our study analyzed 359 intracranial aneurysms from 268 patients, reconstructing patient-specific models for hemodynamic simulations based on 3D rotational angiographic images and intraoperative videos. We identified aneurysm subregions and delineated rupture sites, characterizing blebs and their regional overlap, employing statistical comparisons across demographics, and other risk factors. This work identifies patterns in aneurysm rupture sites, predominantly at the dome, with variations across patient demographics. Hypertensive and anterior communicating artery (ACom) aneurysms showed specific rupture patterns and bleb associations, indicating two pathways: high-flow in ACom with thin blebs at impingement sites and low-flow, oscillatory conditions in middle cerebral artery (MCA) aneurysms fostering thick blebs. Bleb characteristics varied with gender, age, and smoking, linking rupture risks to hemodynamic factors and patient profiles. These insights enhance understanding of the hemodynamic mechanisms leading to rupture events. This analysis elucidates the role of localized hemodynamics in intracranial aneurysm rupture, challenging the emphasis on location by revealing how flow variations influence stability and risk. We identify two pathways to wall failure-high-flow and low-flow conditions-highlighting the complexity of aneurysm behavior. Additionally, this research advances our knowledge of how inherent patient-specific characteristics impact these processes, which need further investigation.
颅内动脉瘤形成和破裂的机制尚未完全阐明，位置、患者人口统计学特征和血液动力学等因素都起着作用。此外，在破裂中像瘤样突起这样的解剖特征的意义也存在争议。这突出表明需要进行综合研究，将患者特定的危险因素与在瘤样突起和破裂部位的局部血液动力学特征的详细分析相结合。我们的研究分析了 268 名患者的 359 个颅内动脉瘤，根据 3D 旋转血管造影图像和术中视频为血液动力学模拟重建了患者特定的模型。我们确定了动脉瘤的亚区和破裂部位，描绘了瘤样突起及其区域重叠，并通过人口统计学和其他危险因素进行了统计比较。这项工作确定了动脉瘤破裂部位的模式，主要在瘤顶，不同患者的特征存在差异。高血压和前交通动脉（ACom）动脉瘤显示出特定的破裂模式和瘤样突起的关联，表明存在两种途径：ACom 中血流高且在冲击部位有薄的瘤样突起，大脑中动脉（MCA）动脉瘤中血流低且有振荡条件，促进了厚的瘤样突起。瘤样突起特征随性别、年龄和吸烟状况而变化，将破裂风险与血液动力学因素和患者特征联系起来。这些见解增强了对导致破裂事件的血液动力学机制的理解。这项分析阐明了局部血液动力学在颅内动脉瘤破裂中的作用，通过揭示流量变化如何影响稳定性和风险，挑战了对位置的重视。我们确定了两种导致壁破裂的途径——高流量和低流量条件——突出了动脉瘤行为的复杂性。此外，这项研究增进了我们对特定患者特征如何影响这些过程的认识，这需要进一步研究。
