Sample-specific computational fluid dynamics of vascular network functionality

Abstract

One of the main factors to control in the development of tissue engineering scaffolds is the growth of new blood vessels and the posterior formation of vascular networks, which is consider as a critical factor because of the transport of nutrients and oxygen to the surrounding cells. Nowadays, computational modeling is presented as a useful support tool to provide a better understanding of vascular networks functionality. Therefore, the analysis of large-scale computational fluid flow dynamics (CFD), allows us to obtain the local parameters associated to mechanical stimuli affecting the microenvironment (scaffolds) and tissue involved (vascular cells). This study has developed a robust methodology to perform a quantitative assessment of vascular networks functionality based on numerical simulations. The methodology to perform the CFD analyses presented in this study is based on two different samples. The vascular networks were obtained by Synchrotron and Micro-Computed Tomography provided by the Swiss Federal Institute of Technology Zurich in DICOM file format. The DICOM files were imported in Simpleware to obtain a three dimensional reconstruction, superficial and solid mesh of the vascular networks. Due to the complexity of the structure and the amount of data generated, an optimization scheme was defined to reduce computing time while maintaining the accuracy of the results. Once the mesh was obtained, the boundary conditions and the properties of the fluid were defined in Fluent and Tdyn to simulate blood movement from the superior to inferior position. The results allowed us to interpret the mechanical phenomenon involved in the angiogenesis process and the importance of cellular responses to mechanical stimuli in tissue engineering applications.