Abstract:
The Circle of Willis (CoW) describes the arterial system in the human brain enabling the neurovascular blood supply. Neurovascular diseases like intracranial aneurysms (IAs) can occur within the CoW and carry the risk of rupture, which can lead to subarachnoid hemorrhage. The assessment of hemodynamic information in these pathologies is crucial for their understanding regarding detection, diagnosis and treatment. Multi-dimensional in silico approaches exist to evaluate these hemodynamics based on patient-specific input data. The approaches comprise low-scale (zero-dimensional, one-dimensional) and high-scale (three-dimensional) models as well as multi-scale coupled models. The input data can be derived from medical imaging, numerical models, literature-based assumptions or from measurements within healthy subjects. Thus, the most realistic description of neurovascular hemodynamics is still controversial. Within this systematic review, first, the models of the three scales (0D, 1D, 3D) and second, the multi-scale models, which are coupled versions of the three scales, were discussed. Current best practices in describing neurovascular hemodynamics most realistically and their clinical applicablility were elucidated. The performance of 3D simulation entails high computational expenses, which could be reduced by analyzing solely the region of interest in detail. Medical imaging to establish patient-specific boundary conditions is usually rare, and thus, lower dimensional models provide a realistic mimicking of the surrounding hemodynamics. Multi-scale coupling, however, is computationally expensive as well, especially when taking all dimensions into account. In conclusion, the 0D-1D-3D multi-scale approach provides the most realistic outcome; nevertheless, it is least applicable. A 1D-3D multi-scale model can be considered regarding a beneficial trade-off between realistic results and applicable performance.
摘要:
威利斯循环(CoW)描述了人脑中的动脉系统,使神经血管血液供应成为可能。神经血管疾病,如颅内动脉瘤(IAs)可发生在CoW内,并有破裂的风险,会导致蛛网膜下腔出血.这些病理中的血流动力学信息的评估对于他们对检测的理解至关重要。诊断和治疗。存在基于患者特异性输入数据来评估这些血液动力学的多维计算机模拟方法。这些方法包括低尺度(零维,一维)和高尺度(三维)模型以及多尺度耦合模型。输入数据可以来自医学成像,数值模型,基于文献的假设或来自健康受试者的测量。因此,神经血管血流动力学最真实的描述仍然存在争议。在这一系统审查中,首先,三个尺度的模型(0D,1D,3D)和第二,多尺度模型,它们是三个音阶的耦合版本,进行了讨论。阐明了最现实地描述神经血管血流动力学的当前最佳实践及其临床应用。3D模拟的性能需要很高的计算费用,这可以通过只详细分析感兴趣的区域来减少。建立患者特定边界条件的医学成像通常很少见,因此,低维模型提供了对周围血液动力学的真实模拟。多尺度耦合,然而,计算成本也很高,尤其是在考虑所有维度的时候。总之,0D-1D-3D多尺度方法提供了最现实的结果;然而,它是最不适用的。关于现实结果和适用性能之间的有益折衷,可以考虑1D-3D多尺度模型。