Intraoperative 3D Shape Estimation of Magnetic Soft Guidewire

Abstract

This paper introduces a 3D shape reconstruction technique for interventional devices in endovascular surgery, utilizing a flexible magnetic tip guidewire that preserves the fundamental attributes of standard guidewires. We developed a model that correlates the magnetic tip's shape with the surrounding magnetic field distribution to estimate the shape through the magnetic field. The inherently nonlinear relationship between the magnetic field distribution and the shape of the magnetic guidewire presents challenges for direct shape estimation. To address this, we incorporated image and physical constraints to streamline the estimation process. This method shows high accuracy and stability in shape estimation, with root mean square error (RMSE) and Hausdorff distance (HD) both below 1 mm, which is better than other existing estimation methods. Notably, the interventional guidewire requires no embedded sensors or wiring, and the fluoroscopic images used are standard in clinical practice. The reconstruction process is non-disruptive to clinical procedures, suggesting broad applicability in vascular interventional navigation.