A convergent magnetic stereotaxis system for guidance to a target

摘要

A guidance system for guiding a surgical instrument without visual information to a target in tissue. The system centers the target upon the trajectory of an infinite family of zero-flux curvilinear lines emanating from either a fixed magnet or an ac or dc electromagnet which is mounted on the instrument. The approach to the target allows selection of straight and curved trajectories based on the zero-flux lines that intersect the target. A self-centering attachment that holds the magnet allows any straight instrument to be guided by the system. The zero-flux lines are measured by a magnetometer that is located on a remote location on or in the tissue. The transducers of the magnetometer measure the magnetic field strength that is present if the instrument deviates from the zero-flux line. The guidance information is plotted on a display that allows a user to guide the instrument along the zero-flux line to the target. An alternative embodiment uses a sensing magnetometer in the instrument tip that measures the field strength that is generated from a magnet that is placed on a remote location on or in the tissue.