Computational fluid dynamics (CFD) simulation provides valuable information on blood flow from the vascular geometry. However, it requires to extract accurate models of arteries from low resolution medical images, which remains challenging. Centerline-based representation is widely used to model large vascular networks with small vessels, as it enables manual editing and encodes the topological information. In this work, we propose an automatic method to generate an hexahedral mesh suitable for CFD directly from centerlines. The proposed method is an improvement of the state-of-the-art in terms of robustness, mesh quality and reproductibility. Both the modeling and meshing tasks are addressed. A new vessel model based on penalized splines is proposed to overcome the limitations inherent to the centerline representation, such as noise and sparsity. Bifurcations are reconstructed using a physiologically accurate parametric model that we extended to planar n-furcations. Finally, a volume mesh with structured, hexahedral and flow oriented cells is produced from the proposed vascular network model. The proposed method offers a better robustness and mesh quality than the state-of-the-art methods. As it combines both modeling and meshing techniques, it can be applied to edit the geometry and topology of vascular models effortlessly to study the impact on hemodynamics. We demonstrate the efficiency of our method by entirely meshing a dataset of 60 cerebral vascular networks. 92\% of the vessels and 83\% of the bifurcations where mesh without defects needing manual intervention, despite the challenging aspect of the input data. The source code will be released publicly.
翻译:剖析流体动态模拟(CFD)为血管几何测量血液流动提供了宝贵的信息。然而,它需要从低分辨率医学图像中提取准确的动脉模型,这仍然具有挑战性。基于中线的表示方式被广泛用来模拟与小型船只的大型血管网络,因为它能够进行手工编辑和编码表层信息。在这项工作中,我们提出了一个自动方法,从中线直接产生适合CFD的六合体网块。提议的方法是改善结构、网状质量和再生能力方面的先进运动。模型和网形网络的模拟和网形任务都得到了解决。基于受罚的螺旋体样的新船只模型被广泛用于模拟血管网络的大型血管网络,以克服中线代表本身固有的局限性,例如噪音和松动。正在利用一种生理精确的参数模型进行重建。最后,一个具有结构性、十六合体和以运动方向方向为方向的细胞结构的体积结构的精度结构模型,从血管网络模型、网状质量和网状图中可以展示一种更坚固的模型。我们所应用的方法可以用来将结构化和结构精度的计算方法进行推算。我们所使用的方法可以用来用来将它的模和结构化的计算方法用于结构的模模模模模模的模的模精度的精度的模精度,它的计算方法可以用来用来用来用来将它的研磨制成成的模的模的模的模法的模。它的模法的模法的模法的模法的模法度和模法度,它的模法度,它的模法度,用来用来用来用来用来用来用来用来用来用来用来用来用来用来用来使它的模。它的模。它比比比的模的模的模。它的精度和模的模制的模的模的模的模的模的模的模的模的模的模的模法度和模的精度,它的精度,它的精度的精度的精度的精度的精度和模的精度的精度的精度的精度的精度的精度的精度的精度的精度的精度的精度的精度的精度的精度的精度的精度,它比的精度,它的精度