3D Turbulent Computational Fluid Dynamic Study of Catheter Tip Geometries for the Optimization of Spreading and Mixing of Drug Solutions

Intra-arterial infusion therapy is an effective treatment of localized malignant diseases. These therapies reduce systemic toxicity and enhance tumor response. However, poor mixing and non-uniform drug dispersion can lead to a buildup of toxic local concentrations and thereby decrease the effectiveness of the therapy. In this study, we investigate the mixing properties of six catheters with varying tip geometries to address the problem of local toxicity. Using a 3D, turbulent, incompressible, multiphase, unsteady formulation, the goal of the study is to qualitatively compare and determine which catheter-tip geometries produce the most optimal mixing characteristics distal to the catheter tip and deliver the highest drug concentration to the vessel walls. The open-source code OpenFOAM is used to model the blood and drug flow dynamics. Our results show that catheters modified with side holes exhibit increased spreading rates and mixing properties, at the same time reducing the tip velocities. The simulations also show that lower-viscosity drugs have identical jet structures as higher-viscosity fluids at fixed flow rates. However, lower-viscosity fluids are better suited for infusion therapy because they can maximize flow rate with the least damage to the blood-vessel wall.