External Charger with Customizable Magnetic Charging Field

• US 20110276111A1
• Filed: 05/03/2011
• Published: 11/10/2011
• Est. Priority Date: 05/07/2010
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Inventors: Whitehurst, Todd, Carbunaru, Rafael, DiGiore, Andrew
• Granted Patent: US 9,700,730 B2
• Time in Patent Office: Days
• US Class Current: 607/61
• CPC Class Codes: A61N 1/37205 Microstimulators, e.g. implantable through a cannula
• CPC Class Codes: A61N 1/37211 Means for communicating with stimulators
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/378 Electrical supply
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

Improved external chargers for charging an implantable medical device, and particularly useful in charging a plurality of such devices, are disclosed. Each of the various embodiments include a plurality of field customization coils for customizing the magnetic charging field generated by the external charger such that the magnetic charging field is not radially symmetric. For example, one embodiment includes a primary coil with a plurality of field customization coils distributed radially with respect to the coil. The generated magnetic charging field can be rendered radially asymmetric by selectively activating or disabling the field customization coils in response to data quantifying the coupling between the various implants and the field customization coils in the charger. If there is a relatively high coupling between a particular implant and a particular customization coil for example, that customization coil can be activated to counter the magnetic charging field at that location, while still maintaining a relatively high magnetic charging field at the location of other implants that may have lower couplings.

Claims

1. An external charger for charging at least one implantable medical device, comprising:

a primary charging coil; and

a plurality of first coils,

wherein the plurality of first coils are differently activatable to produce a radially asymmetric magnetic charging field in conjunction with activation of the primary charging coil.

2. The external charger of claim 1, wherein the plurality of first coils are positioned radially symmetrically with respect to the primary charging coil.

3. The external charger of claim 1, wherein the plurality of first coils are located within an area extent of the primary charging coil.

4. The external charger of claim 1, further comprising a memory for storing a plurality of coupling parameters, and wherein the plurality of first coils are differently activatable in accordance with at least one of the coupling parameters.

5. The external charger of claim 4, wherein each coupling parameter is indicative of the coupling between the external charger and one of the implantable medical devices.

6. The external charger of claim 5, wherein each coupling parameter is indicative of the coupling between one of the coils and one of plurality of implantable medical devices.

7. The external charger of claim 4, wherein each coupling parameter is indicative of the coupling between one of the coils at least one of the implantable medical devices.

8. The external charger of claim 1, wherein the first coils are differently activatable by being configurable to carry different customization currents.

9. The external charger of claim 1, wherein the first coils are differently activatable by being configurable to be coupled in series with the primary charging coil.

10. The external charger of claim 1, wherein the first coils are differently activatable by being selectively openable or closeable.

11. An external charger for charging at least one implantable medical device, comprising:

a plurality of first coils; and

a memory for storing a plurality of coupling parameters indicative of the coupling between the external charger and at least one implantable medical device,

wherein the plurality of first coils are differently activatable in accordance with at least one of the coupling parameters to produce a radially asymmetric magnetic charging field.

12. The external charger of claim 11, wherein the plurality of first coils are positioned radially symmetrically.

13. The external charger of claim 11, wherein each coupling parameter is indicative of the coupling between the external charger and one of the implantable medical devices.

14. The external charger of claim 11, wherein each coupling parameter is indicative of the coupling between one of the coils and one of the implantable medical devices.

15. The external charger of claim 11, wherein each coupling parameter is indicative of the coupling between one of the coils at least one of the implantable medical devices.

16. The external charger of claim 11, wherein the first coils are differently activatable by being configurable to carry different customization currents.

17. The external charger of claim 11, further comprising a primary charging coil, wherein the first coils are differently activatable by being configurable to be coupled in series with the primary charging coil.

18. The external charger of claim 11, wherein the first coils are differently activatable by being selectively openable or closeable.

19. A method for charging a plurality of implantable medical devices using an external charger comprising a plurality of coils, the method comprising:

differently activating the plurality of coils in the external charger to generate a radially-asymmetric magnetic charging field,

wherein the radially-asymmetric magnetic charging field is configured to uniformly charge the plurality of implantable medical devices.

20. The method of claim 19, wherein the plurality of the plurality of coils are differently activated in accordance with coupling parameters each indicative of the coupling between one of the plurality of coils and at least one of the implantable medical devices.

21. The method of claim 20, wherein there are n coils and x implantable medical devices, and wherein there are n times x coupling parameters.

22. The method of claim 19, wherein the plurality of coils are differently activated by carrying different customization currents.

23. The method of claim 19, wherein the external charger further comprises a primary charging coil, and wherein the plurality coils are differently activated by some but not all of the plurality of coils being coupled in series with the primary charging coil.

24. The method of claim 19, wherein the plurality of coils are differently activated by some but not all of the plurality of coils being closed or by some but not all of the plurality of coils being opened.

25-29. -29. (canceled)

30. A method for charging a plurality of implantable medical devices using an external charger comprising a plurality of coils, the method comprising:

receiving a plurality of coupling parameters at the external charger, wherein each coupling parameter is indicative of the coupling between the external charger and one of the implantable medical devices; and

generating a magnetic charging field at the external charger,

wherein generating the magnetic charging field comprises differently activating the plurality of coils to adjust the magnetic charging field in accordance with at least one of the coupling parameters.

31. The method of claim 30, wherein the generated magnetic field is radially asymmetric with respect to the external charger.

32. The method of claim 30, wherein each coupling parameter is indicative of the coupling between one of the coils and one of the plurality of implantable medical devices.

33. The method of claim 30, wherein the received plurality of coupling parameters are transmitted by the plurality of implantable medical devices.

34. The method of claim 33, wherein the received plurality of coupling parameters are transmitted by the plurality of implantable medical devices to a primary coil in the external charger.

35. The method of claim 33, wherein the plurality of coupling parameters comprises a voltage within the power circuitry of the plurality of implantable medical devices.

36. The method of claim 33, further comprising producing a test magnetic field from each of the coils to produce the coupling parameters in the plurality of implantable medical devices.

37. A method for charging a plurality of implantable medical devices using an external charger comprising a plurality of coils, the method comprising:

receiving a plurality of coupling parameters at the external charger, wherein each coupling parameter is indicative of the coupling between one of the coils and at least one of the implantable medical devices; and

generating a magnetic charging field at the external charger,

wherein generating the magnetic charging field comprises differently activating the plurality of coils to adjust the magnetic charging field in accordance with at least one of the coupling parameters.

38. The method of claim 37, wherein the generated magnetic field is radially asymmetric with respect to the external charger.

39. The method of claim 37, wherein the received plurality of coupling parameters are measured at the external charger.

40. The method of claim 39, wherein the coupling parameters comprise voltages across the plurality of coils.

41. The method of claim 40, further comprising producing a test magnetic field from each of the coils to produce the voltages across the plurality of coils.

42. The method of claim 40, further comprising producing a test magnetic field from a primary coil to produce the voltages across the plurality of coils.