A system that uses a magnetic aperture and electromagnets to configure a magnetic shaped field is described. In one embodiment, the system can be used for guiding a catheter or other devices through a patient's body. In further modification of the system, the waveguide field and field gradient is achieved...http://www.google.ca/patents/US20100305402?utm_source=gb-gplus-sharePatent US20100305402 - METHOD AND APPARATUS FOR MAGNETIC WAVEGUIDE FORMING A SHAPED FIELD EMPLOYING A MAGNETIC APERTURE FOR GUIDING AND CONTROLLING A MEDICAL DEVICE
