Modeling of magnetic soft catheters in contact with aneurysms

Magnetic soft catheters (MSCs) represent a breakthrough for remote navigation in minimally invasive endovascular procedures, especially in the coil embolization of cerebral aneurysms. However, current MSC models often neglect the contact interaction between the catheter and the aneurysm boundary during navigation, which limits their real-world use. To address this issue, this paper introduces a detailed theoretical model that considers the magneto-mechanical behavior of MSCs and the contact with aneurysms in endovascular environments. The navigation of MSCs through aneurysms of different shapes, such as circular, elliptic, and rounded-elliptic, is investigated to simulate the various anatomical constraints in clinical practice. We present a numerical framework based on polynomial approximations and weighted residuals to analyze the deflections of MSCs in contact with aneurysms under varying magnetic fields. A parametric analysis further explores the impact of magnetic field strength, magnetic field direction, catheter flexibility, and aneurysm wall shape, allowing adjustments to ensure safe navigation. We also examine how these factors affect MSC’s ability to navigate different aneurysm shapes, offering insights for optimizing design strategies for practical use. The proposed model is validated through finite element method (FEM) simulations and experiments, accurately predicting large deformations of MSCs in contact with aneurysms in endovascular environments. The results provide key guidelines for safely navigating MSCs, thus reducing the risk of incorrect coil placement during embolization and laying a solid foundation for the clinical application of MSCs in endovascular procedures.