High-Precision Magnetic Tracking With Individual Magnet Identification for Medical Applications

Permanent magnetic tracking can accurately track the surgical target within the human body via the embedded miniaturized magnet, such as in the tracking of implantable devices and minimally invasive surgical navigation. The measurement accuracy directly affects the safety and effectiveness in these surgical scenarios. Due to inevitable parameter perturbances of the miniaturized magnet, it is difficult to enhance the measurement accuracy using nominal parameters. In this article, an identified parameter-based magnetic tracking is proposed to enhance measurement accuracy, where the identified parameters are used in the tracking algorithm to attenuate the influence of parameter perturbations. Simulation results verify the ultrahigh fidelity of the established model of the magnet. Static and dynamic trajectory experiments further validate the effectiveness and applicability of this method at different positions and under various motion patterns. Compared with conventional methods, the proposed method enhances the position accuracy by 65.24% and the orientation accuracy by 41.35% on average. Finally,ex vivotissue experiments verify the feasibility of tracking the tip of a surgical tool in surgical scenarios. The results demonstrate that the proposed method effectively attenuates the influence of parameter perturbations on measurement accuracy and provides reliable technical support for clinical applications.