Design of a magnetic localisation system for in-vivo endovascular interventions

Endovascular catheterisation is performed by an interventional radiologist using fluoroscopic guide and contrast-media. The X-Ray exposure both of the patient and of the operators can induce heavy collateral effects. The present paper describes an innovative magnetic position/orientation indicator capable to drive the endovascular probe during in-vivo medical diagnostic or interventional procedures. It uses the magnetic field produced by a thin permanent magnet installed on the endovascular probe and magnetic field sensors positioned outside the patient body: this allow the elimination of repetitive X-Ray scans used to monitor the probe position. The aims of the proposed system are: to drive the catheter inside the patient vascular tree with a reduction of the X-Ray exposure both of the patient and of the personnel involved in the intervention; to allow a more comfortable operative condition for the personnel due to the reduction of the time they wear X-Ray protective systems. The paper reports the mathematical problem formulation, the numerical simulations for the magnetic field calculation produced by the thin endovascular permanent magnet and the system design of the usable hardware.