Open field system for magnetic surgery

Abstract

A system of navigating a magnetic medical device within that part of a patient located within an operating region of the system, the system comprising magnets, and preferably electromagnets, arranged to provide a magnetic field sufficient to navigate the magnetic medical device within the operating region. There are preferably three magnetic coils arranged in mutually perpendicular planes such that their axes intersect in the operating region. The magnetic coils are sized and arranged so that a patient can easily access the operating region to allow virtually any portion of the patient to be positioned within the operating region. The openness of the magnetic system allows access to the operating region by a bi-planer imaging system.

1 - 19 . (canceled) 
     
     
         20 . A system for navigating a magnetic medical device comprising a plurality of magnet coils for applying a magnetic field in a particular direction to orient a magnetic medical device within that part of a patient located within an operating region of the system in a selected direction, a plurality of magnet coils being effective to controllably orient the medical device within substantially the entirety of the operating region, said operating region being positioned so that said part of the patient may be located within the operating region without passing through any of said magnet coils. 
     
     
         21 . A system for navigating a magnetic medical device according to  claim 20 , further comprising at least three magnet coils configured and arranged in an open concave shell to provide a magnetic field effective within the operating region to orient the magnetic medical device in a selected direction within the operating region. 
     
     
         22 . A system according to  claim 21 , wherein the coils are arranged in a generally hemispherically shaped shell. 
     
     
         23 . A system according to  claim 21 , wherein the shell is mounted for rotation about a vertical axis. 
     
     
         24 . A system according to  claim 20 , wherein the plurality of magnet coils are generally aligned along a plurality of oblique axes with only a single one of said magnet coils being aligned along one of said axes, and at least one of the magnet coils being aligned along the others of said axes. 
     
     
         25 . A system according to  claim 20 , wherein the magnet coils are capable of providing a magnetic field of at least substantially 0.1 Tesla anywhere in an operating region of at least 50.8 mm by 50.8 mm by substantially 50.8 mm. 
     
     
         26 . The system according to  claim 20 , wherein the operating region has a volume of at least substantially 127 mm by substantially 127 mm by substantially 127 mm. 
     
     
         27 . A system according to  claim 20 , wherein the magnet coils are arranged and configured so that their axes intersect, and wherein the coils are spaced sufficiently from the point of intersection to accommodate a sphere centered on the point of intersection, with a radius of at least 304.8 mm. 
     
     
         28 . The system according to  claim 21 , further comprising a support for the patient, and a moveable support for the shell so that said shell may be reoriented about said patient support and patient. 
     
     
         29 . A system according to  claim 20 , wherein said magnet coils are positioned so that their respective near field lines are substantially straight within the operating region. 
     
     
         30 . A system for navigating a magnetic medical device within that part of a patient located within an operating region of the system, the system comprising:
 a patient support for supporting a patient, and   at least three electromagnet coils forming a magnet assembly positioned above the plane of the patient support, being configured and arranged to provide a magnetic field effective within the operating region to navigate the magnetic medical device within the operating region, the at least three electromagnet coils being positioned above the plane of the patient support and arranged such that the axes of the electromagnet coils intersect generally in the center of an operating region of the magnet assembly;   wherein the patient support is movable and has a narrow portion that is sized to fit within the magnet assembly to allow a portion of the patient's body, up to and including a patient's chest, to be positioned within the operating region of the magnet assembly.   
     
     
         31 . A system according to  claim 30 , wherein the spacing of the electromagnetic coils provide an opening of sufficient size such that a patient's chest can be positioned within the operating region. 
     
     
         32 . A system according to  claim 31 , wherein the intersection of the axes of the magnet is coiled is at least about 150 mm (six inches) from each of the coils, but no more than about 375 mm (fifteen inches) from each of the coils. 
     
     
         33 . A system according to  claim 31  wherein the electromagnet coils are configured and arranged to be able to provide a magnetic field of at least about 0.1 Tesla within an operating region which operating region is spaced at least about 300 mm (twelve inches) from each of the coils, to selectively orient the magnetic medical device anywhere within the operating region. 
     
     
         34 . A system according to  claim 33 , wherein the electromagnetic coils are capable of providing a magnetic field of at least about 0.3 Tesla anywhere within the operating region. 
     
     
         35 . A system according to  claim 33 , wherein the axes of the three electromagnetic coils are mutually perpendicular. 
     
     
         36 . A system according to  claim 31 , wherein the electromagnetic coils are mounted in a shell having a generally concave shape. 
     
     
         37 . A system for navigating a magnetic medical device within that part of a patient located within an operating region of the system, the system comprising: three magnets configured and arranged to provide a magnetic field effective within the operating region to navigate the magnetic medical device within the operating region. 
     
     
         38 . A system according to  claim 37 , wherein the magnets are electromagnetic coils having intersecting axes. 
     
     
         39 . A system according to  claim 38 , wherein the intersection of the axes of the magnets is at least about six inches from each of the coils, but no more than about fifteen inches from each of the coils.