Fluid-structure interaction analysis of carotid artery stenosis: Impact of concentric versus eccentric morphologies...

The research on arterial stenosis has gained rapid attention in the last decade due to its severe consequences and chronicity. The morphological analysis of a stenosis plays a crucial role in understanding the physiological characteristics and its treatment strategies because alteration of stenoses' shapes and their structure significantly changes the hemodynamics in the nearby region and may affect their progression.

In this study, three common shapes of stenosis - round, oval, and elongated - located at the vulnerable point, the carotid sinus, have been discussed, along with their shape concentricity and eccentricity. The hemodynamics of these shapes of stenosis, along with their concentricity and eccentricity, have been explored in this study. A total of six cases (three different shapes of stenosis, and their concentricity and eccentricity) were discussed, and their hemodynamic parameters were described. The study performed a numerical analysis under Fluid-Structure Interaction (FSI) multiphysics.

After comparing all the hemodynamic parameters, it was found that which parameter is most suitable for distinguishing between different stenosis shapes. To analyse this, a phase shift and Root Mean Square Deviation (RMSD) were calculated for every parameter. It was found that the phase shift in case of velocity profile showed a maximum value of 15.79% and 10.53% in concentric and eccentric round cases, respectively, distinguishing it from the other two shapes. Similarly, the phase shift profile in displacement separated out the elongated shape, which had the minimum values. The eccentric and concentric round, elongated, and oval shapes were clearly distinguished when they were analysed using RMSD velocity and displacement profile, as they had a unique value of RMSD in each case.

By analysing different hemodynamic parameters in a stenosed carotid artery, this paper showed that a specific shape of stenosis can be distinguished from the others. This information is valuable for researchers and doctors dealing with carotid stenosis and can be a useful reference during preoperative planning and surgical intervention for stenosis.