| 摘要 |
<p>A guidance system (10) for guiding a surgical instrument (12) without visual information to a target (14) in tissue. The system (10) centers the target (14) upon the trajectory of an infinite family of zero-flux curvilinear lines emanating from either a fixed magnet (30) or an ac or dc electromagnet which is mounted on the instrument (12). The approach to the target (14) allows selection of straight and curved trajectories based on the zero-flux lines that intersect the target (14). A self-centering attachment (32) that holds the magnet (30) allows any straight instrument (12) to be guided by the system (10). The zero-flux lines are measured by a magnetometer (34) that is located on a remote location on or in the tissue. The transducers (38, 40, 42) of the magnetometer (34) measure the magnetic field strength that is present if the instrument (12) deviates from the zero-flux line. The guidance information is plotted on a display (50) that allows a user to guide the instrument (12) along the zero-flux line to the target (14).</p> |
