Gradiometer-Based Magnetic Localization for Medical Tools

Abstract

Remote magnetic navigation offers various possibilities for medical interventions. Magnetic catheters can be wirelessly steered with high precision and accuracy through complex structures, as they are generally more dexterous and flexible than their manually steered counterparts. Position feedback is essential for many tasks. However, most commercially available systems do not integrate well with the magnetic navigation systems. As a result, fluoroscopy is still widely used in many interventions despite the known associated health risks.In this study, we propose a localization method that uses multiple Hall sensors to measure the magnetic fields produced by the magnetic navigation system and estimate the full sensor pose without the need for a separate dedicated mapping system. This makes the magnetic navigation system a 2-in-1 system that can be used for simultaneous navigation and localization of a medical tool.We perform an optimization of the sensors' array design in simulation and investigate the influence of the magnetic fields and gradients on the localization accuracy to provide information on the minimal requirements for a magnetic navigation system for this task.

Simultaneous Localization and Actuation Using Electromagnetic Navigation Systems

“…In certain applications, the magnetic object to be actuated can also be continuous, such as magnetic continuum robots [18], or the localization of multiple sensors within the workspace may be required. The use of constant magnetic field gradients generated by an electromagnetic navigation system (eMNS) to localize magnetic devices using a single three-axis Hall sensor was investigated in [19], [20]. However, using a constant magnetic field and the measurement of a single magnetic sensor is not enough to determine its pose without incurring additional geometric constraints or applying changing magnetic fields, both being detrimental to a simultaneous actuation.…”

Eigenvector Constraint-Based Method for Eliminating Dead Zone in Magnetic Target Localization

“…It is also employed in detecting unexploded ordnance, where it helps identify and safely remove potential threats [3,4]. In medical interventions, this technology is applied in steering magnetic catheters and tracking wireless biomedical capsule [5,6]. The dominant approach adopted in magnetic target localization is the analytical method, which leverages the relationship between the magnetic field vector, the magnetic gradient tensor (MGT), and the tensor invariant to derive the localization formula.…”