System for mechanical adjustment of medical implants

• US 20090076597A1
• Filed: 09/19/2007
• Published: 03/19/2009
• Est. Priority Date: 09/19/2007
• Status: Abandoned Application

• Current Assignee: Kardium Inc.
• Original Assignee: Kardium Inc.
• Inventors: Dahlgren, Jonathan Micheal, Gelbart, Daniel
• Application Number:
  US11/902,099
• Publication Number:
  US 20090076597A1
• Time in Patent Office: Days
• US Class Current: 623/2.100
• CPC Class Codes: A61B 17/7016 electric or electromagnetic means
• CPC Class Codes: A61B 17/7216 for bone lengthening or compression A61B17/7258 takes precedence
• CPC Class Codes: A61B 2017/00212 using remote controls
• CPC Class Codes: A61B 2017/00411 actuated by application of energy from an energy source outside the body
• CPC Class Codes: A61B 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61F 2/2445 Annuloplasty rings in direct contact with the valve annulus
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• CPC Class Codes: A61F 2002/30079 magnetic
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30668 Means for transferring electromagnetic energy to implants
• CPC Class Codes: A61F 2210/009 magnetic
• CPC Class Codes: A61F 2250/0001 Means for transferring electromagnetic energy to implants
• CPC Class Codes: A61F 2250/0006 for adjusting angular orientation

Abstract

A system for mechanically adjusting medical implants uses an external coil to set up a magnetic field. The magnetic field causes an actuator inside the implant to move in small steps, allowing fine adjustment. The element responding to the magnetic field can be magnetostrictive or SMA based. Large motions are made up from small steps by using two one-way clutches allowing the active element to move small increments in one direction. For SMA based devices, short burst of AC magnetic field are used. For magnetostrictive devices short pulse of unipolar magnetic field are used.

Claims

1. A medical implant capable of non invasive step-by-step adjustment in response to a changing external magnetic field.

6. An implant as in claim 1 wherein said adjustment is bi-directional.

7. An implant as in claim 1 comprising a shape memory alloy.

8. An implant as in claim 1 comprising a magnetostrictive alloy.

9. An implant as in claim 1 comprising a Terfenol-D alloy.

10. An implant as in claim 1 comprising a Ni—

Mn-GA alloy.

11. An implant as in claim 1 wherein said system comprises a piezoelectric material.

12. An implant as in claim 1 comprising of at least two actuators capable of being selectively activated using different parameter of said external magnetic field.

14. An implant as in claim 1 wherein said implant comprises permanent magnets.

15. An implant as in claim 1 compatible with MRI imaging.

18. An implant as in claim 1 comprising a magnetostrictive element placed between two one-way clutches inside a sealed tube, said element capable of changing the dimension of said implant in response to an externally created magnetic field.

19. An implant as in claim 1 comprising a shape memory alloy element placed between two one-way clutches inside a sealed tube, said element capable of changing the dimension of said implant in response to heating induced in a non-invasive manner.

2. A system for mitral valve repair including an actuator capable of step-by-step adjustment, said steps activated by a changing magnetic field.

4. A system as in claim 2 delivered to the mitral valve via a catheter in a percutaneous procedure.

5. A system as in claim 2 also used as an anchor for an artificial mitral valve.

16. A system as in claim 2 compatible with MRI imaging

17. A system as in claim 2 compatible with MRI imaging

3. A orthopedic correction system using step-by-step adjustment activated by a changing magnetic field.

13. A system as in claim 3 wherein a plurality of actuators are attached to the spine allowing non-invasive gradual adjustments.