Magnetic targeting system and method of using the same

Abstract

The present invention describes a magnetic targeting system suitable for guiding a biocompatible device to a target area within the body (in vivo) and method of using the same. The system includes a targeting member having a steering material and is attached to the biocompatible device. The system also includes at least one anchoring member constructed and arranged for the inclusion of a magnetic material effective for influencing the traversal of the steering material, in vivo. The magnetically influenced anchoring member interacts with the targeting member such that the biocompatible device is positionable relative to the target area.

What is claimed is: 
     
       1. A method for facilitating navigation to a target area in vivo, comprising: providing a targeting member having a first end and a second end, said second end attached to a biocompatible device by a tether, wherein said first end includes a steering material influenced by a magnetic field; attaching to said target area in vivo at least two anchoring members, each said anchoring member having a proximal end and a distal end, wherein each said anchoring member is attached to said target area at its distal end; an extender coupled to each said anchoring member, said extender having an open top at said proximal end and an aperture juxtaposed to a bottom of said extender at said distal end; introducing a magnetic material into said proximal end of said anchoring member capable of influencing the traversal of said steering material, thereby positioning said biocompatible device relative to said target area; said targeting member is of a size which enables said targeting member to pass into said extender through said top of said extender, through said extender and out of said extender through said aperture of said extender, said targeting member is also of a size which enables said targeting member to pass into said extender through said aperture, through said extender and out of said extender through said open top; passing said targeting member through said open top of first extender, through said first extender and out of said first extender through said aperture of said first extender, also passing said targeting member into second extender through said aperture, through said second extender and out of said second extender through said open top of said second extender. 
     
     
       2. The method as set forth in  claim 1 , wherein said system includes a real-time feedback mechanism to verify location in vivo of said biocompatible device. 
     
     
       3. The method as set forth in  claim 2 , wherein said real-time feedback mechanism includes tactile feedback to verify location in vivo of said biocompatible device. 
     
     
       4. The method as set forth in  claim 1 , wherein
 said magnetic material is an electromagnet.   
     
     
       5. The method as set forth in  claim 1 , wherein said magnetic material is a permanent magnet. 
     
     
       6. The method as set forth in  claim 1  wherein said biocompatible device is an implant or surgical instrument. 
     
     
       7. The method as set forth in  claim 1  wherein said biocompatible device is formed from a material selected from the group consisting of rigid, semi-rigid, or flexible. 
     
     
       8. The method as set forth in  claim 1 , wherein said anchor member is a fastening means for attaching to a bony structure and said biocompatible device is an interconnecting means. 
     
     
       9. The method as set forth in  claim 1 , wherein said targeting member is formed from a material selected from the group consisting of rigid, semi-rigid, or flexible. 
     
     
       10. A method for facilitating navigation of a biocompatible device to a target position connecting anchoring members secured in vivo, comprising:
 securing first and second anchor members to a body structure located in vivo, said first and second anchoring members each having a distal end configured to secure to a body structure located in vivo and a proximal end including a connector with a transverse passage configured to receive a portion of a biocompatible device, the biocompatible device being lockable to the first and second anchoring member connectors with locking members that engage the connectors, the first connector releasably coupled to a first extender and the second connector releasably coupled to a second extender, each of said first extender and said second extender having an interior passage that extends along the length of the extender between a proximal end opening and a distal end opening, the interior passage sized to receive a locking members therethrough and a driver associated with the locking members, each of the first extender and second extender also having an aperture in connection with the distal end opening and extending transversely through the interior passage, and a slot in connection with the aperture and extending towards the proximal end along a length of the extender;   advancing a targeting member to a first position proximate the aperture of the first extender, the targeting member having a first end and a second end, said second end attached to the biocompatible device by a tether and said first end including a steering material configured to be influenced by a magnetic field;   positioning the distal end of a magnetic device in a second position proximate the aperture of the second extender, the distal end of the magnetic device including a magnetic material configured to influence the steering material of the targeting member, and influencing the targeting member to move from the first position to the second position thereby creating a pathway through the tissue between the first connector and the second connector;   withdrawing the targeting member along the second extender to pull the attached biocompatible device along the pathway into the target position connecting the first and second anchor members; and   advancing a first locking member through the interior passage of the first extender and advancing a second locking member through the interior passage of the second extender to lock the biocompatible member to the first and second anchoring members.   
     
     
       11. The method of claim 10, wherein said magnetic material is an electromagnet and including the additional step of turning on the electromagnet after the distal end of the magnetic device is situated in the second position. 
     
     
       12. The method of claim 11, wherein the magnetic device includes a handle at a proximal end and the handle includes a switch for turning on the electromagnet. 
     
     
       13. The method of claim 12, wherein the handle also includes controls for increasing and decreasing the strength of the electromagnet. 
     
     
       14. The method of claim 10, wherein the magnetic material is a permanent magnet. 
     
     
       15. The method of claim 10, wherein the targeting member is semi-rigid with a portion of the targeting member proximate the first end being made of flexible material. 
     
     
       16. The method of claim 10, wherein the targeting member is rigid. 
     
     
       17. The method of claim 10, wherein the first and second anchoring members are pedicle screws and the step of securing the first and second anchor members to a body structure located in vivo include securing the first pedicle screw to a first vertebra of the spine and securing the second pedicle screw to a second vertebra of the spine. 
     
     
       18. The method of claim 17, wherein the first and second pedicle screws are multi-axis pedicle screws. 
     
     
       19. A method for facilitating navigation of a biocompatible device to a target position connecting anchoring members secured in vivo, comprising:
 securing anchor members to a body structure located in vivo, said anchor members including a first end anchor member, a second end anchor member, and a middle anchor member said first end, second end, and middle anchor members each having a having a proximal end including a connector with a transverse passage configured to receive a portion of a biocompatible device, the biocompatible device being lockable to the first end, second end, and middle anchor member connectors with locking members that engage the connectors, the first connector releasably coupled to a first extender, the second connector releasably coupled to a second extender, and the middle connector releasably coupled to a middle extender, each of said first extender, second extender and said middle extender having an interior passage that extends along the length of the extender between a proximal end opening and a distal end opening, the interior passage sized to receive locking members therethrough and a driver associated with the locking members, each of the first extender, second extender, and middle extender also having an aperture in connection with the distal end opening and extending transversely through the interior passage, and a slot in connection with the aperture and extending towards the proximal end along a length of the extender;   advancing a targeting member to a first position proximate the aperture of the first extender, the targeting member having a first end and a second end, said second end attached to the biocompatible device by a tether and said first end including a steering material configured to be influenced by a magnetic field;   positioning the distal end of a magnetic device in a second position proximate the aperture of the middle extender, the distal end of the magnetic device including a magnetic material configured to influence the steering material of the targeting member, and influencing the targeting member to move from the first position to the second position thereby creating a pathway through the tissue between the first connector and the middle connector;   positioning the distal end of the magnetic device in a third position proximate the aperture of the second extender and influencing the targeting member to move from the second position to the third position thereby extending the pathway through tissue to the second connector;   withdrawing the targeting member along the second extender to pull the attached biocompatible device along the pathway into the target position connecting the first end, second end, and middle anchor members; and   advancing locking members through the interior passages of each of the first extender, second extender, and middle extender to lock the biocompatible member to the first end, second end, and middle anchor members.   
     
     
       20. The method of claim 19, further comprising multiple middle anchor members secured between the first end anchor member and the second end anchor member, each including a releasably coupled middle extender and wherein the magnetic device is used through each additional middle extender in sequence to move the targeting member to the coupled middle connector from the previous middle connector.