Performance of magnetic field-guided navigation system for interventional neurosurgical and cardiac procedures

Abstract

A hospital-based magnetic guidance system (MGS) was installed to assist a physician in navigating catheters and guide wires during interventional cardiac and neurosurgical procedures. The objective of this study is to examine the performance of this magnetic field-guided navigation system. Our results show that the system's radiological imaging components produce images with quality similar to that produced by other modern fluoroscopic devices. The system's magnetic navigation components also deflect the wire and catheter tips toward the intended direction. The physician, however, will have to oversteer the wire or catheter when defining the steering angle during the procedure. The MGS could be clinically useful in device navigation deflection and vessel access.

Figure 1

Experimental setup showing the surface of the phantom (3) on the table (4) is parallel to the flat panel imager (1) on the left. Superconducting coils (2) are located above each flat panel and around the opening at the center. The catheters and guide wire are placed on the phantom surface during the experiment.

Figure 2

Guide wire and catheters used in the experiment. The outside diameter for the microcatheters (top and bottom) is 0.035“ (2.6 Fr). The guide wire (middle) has a diameter of 0.014”. The magnetic tips of all three devices are clearly visible.

Figure 3

Magnetic field‐induced device tip deflection.

Figure 4

Magnetic field measured with phantom surface parallel to the flat panel imagers. The open and solid symbols are measured with the phantom surface parallel to the left and right flat panel detectors, respectively. The square symbols are for magnetic field parallel to the catheters or wire, and the circles are data points measured in the perpendicular direction. The as expected, that a sine function fits all data measured along the catheter (square symbols). Another sine function with a 90° phase offset describes the data measured in the perpendicular direction (circle symbols). The magnetic field component perpendicular to the phantom surface does not change with steering angle (triangle symbols).