Apparatus and method for shaped magnetic field control for catheter, guidance, control, and imaging

Abstract

A variable magnet system for manipulating a magnetic catheter is described. In one embodiment, a cluster of electromagnets is configured to generate a desired magnetic field. In one embodiment, one or more poles of the cluster are moveable with respect to other poles in the cluster to allow shaping of the magnetic field. In one embodiment, one or more magnetic poles can be extended or retracted to shape the magnetic field. In one embodiment, the electromagnets can be positioned to generate magnetic fields that exert a desired torque and/or movement force on the catheter. In one embodiment, a magnetic field source is used to create a magnetic field of sufficient strength and orientation to move a magnetically-responsive catheter tip in a desired direction by a desired amount.

1 . An apparatus for controlling the movement of a catheter-type tool inside a body of a patient, comprising:
 a magnetic field source for generating a magnetic field, said magnetic field source comprising a first coil corresponding to a first magnetic pole and a second coil corresponding to a second magnetic pole, wherein said first magnetic pole is moveable with respect to said second magnetic pole; and   a system controller for controlling said magnetic field source to control a movement of a distal end of a catheter, said distal end responsive to said magnetic field, said controller configured to control a current in said first coil, a current in said second coil, and a position of said first pole with respect to said second pole.