METHOD AND APPARATUS FOR SUPPLYING ENERGY TO A MEDICAL DEVICE

• US 20100222849A1
• Filed: 10/10/2008
• Published: 09/02/2010
• Est. Priority Date: 10/16/2007
• Status: Active Grant

• Current Assignee: Kirk Promotion Ltd.
• Original Assignee: Kirk Promotion Ltd.
• Inventors: Forsell, Peter
• Granted Patent: US 9,026,222 B2
• Time in Patent Office: Days
• US Class Current: 607/61
• CPC Class Codes: A61B 17/12 for ligaturing or otherwise compressing tubular parts of the body, e.g. blood vessels, umbilical cord specially adapted for vas deferens or fallopian tubes A61F6/20; materials for ligaturing blood vessels A61L17/00
• CPC Class Codes: A61B 2560/0214 of power generation or supply
• CPC Class Codes: A61F 2250/0001 Means for transferring electromagnetic energy to implants
• CPC Class Codes: A61N 1/08 Arrangements or circuits for monitoring, protecting, controlling or indicating for external stimulators A61N1/3603; for implantable neurostimulators A61N1/36128; for heart stimulators A61N1/37; for defibrillators A61N1/3925
• CPC Class Codes: A61N 1/3787 from an external energy source
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/70 involving the reduction of electric, magnetic or electromagnetic leakage fields
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

In a method and apparatus for supplying wireless energy to a medical device (100) implanted in a patient, wireless energy is transmitted from an external energy source (104) located outside a patient and is received by an internal energy receiver (102) located inside the patient, for directly or indirectly supplying received energy to the medical device. An energy balance is determined between the energy received by the internal energy receiver and the energy used for the medical device, and the transmission of wireless energy is then controlled based on the determined energy balance. The energy balance thus provides an accurate indication of the correct amount of energy needed, which is sufficient to operate the medical device properly, but without causing undue temperature rise.

Claims

1. A method of controlling transmission of wireless energy supplied to an electrically operable medical device (100) implanted in a mammal patient, said wireless energy being transmitted by means of a primary coil in an external energy source (104) located outside the patient and received inductively by means of a secondary coil in an internal energy receiver (102) located inside the patient, the internal energy receiver being connected to the medical device for directly or indirectly supplying received energy thereto, wherein feedback control information (S) is transferred from the secondary coil to the primary coil by switching the secondary coil on and off to induce a detectable impedance load variation in the primary coil encoding the feedback control information, where the feedback control information relates to the energy for operating the medical device and is used for controlling the transmission of wireless energy from the external energy source.

2. A method according to claim 1, wherein an energy balance between the energy received by the internal energy receiver and the energy used for the medical device is determined, said feedback control information relating to the determined energy balance, and the transmission of wireless energy from the external energy source is controlled based on the determined energy balance and using said feedback control information.

3. A method according to claim 2, wherein a change in said energy balance is detected, and the transmission of wireless energy is controlled based on said detected energy balance change.

4. A method according to claim 2, wherein a difference is detected between energy received by said internal energy receiver and energy used for the medical device, and the transmission of wireless energy is controlled based on said detected energy difference.

5. A method according to claim 3, wherein the amount of transmitted wireless energy is decreased if the detected energy balance change implies that the energy balance is increasing, or vice versa.

6. A method according to claim 5, wherein the decrease/increase of energy transmission corresponds to a detected change rate.

7. A method according to claim 4, wherein the amount of transmitted wireless energy is decreased if the detected energy difference implies that the received energy is greater than the used energy, or vice versa.

8. A method according to claim 7, wherein the decrease/increase of energy transmission corresponds to the magnitude of said detected energy difference.

9. A method according to claim 3, wherein the energy used for the medical device is consumed to operate the medical device, and/or stored in at least one energy storage device of the medical device.

10. A method according to claim 9, wherein substantially all energy used for the medical device is consumed to operate the medical device.

11. A method according to claim 10, wherein the energy is consumed after being stabilized in at least one energy stabilizing unit of the medical device.

12. A method according to claim 9, wherein substantially all energy used for the medical device is stored in said at least one energy storage device.

13. A method according to claim 9, wherein the energy used for the medical device is partly consumed to operate the medical device and partly stored in said at least one energy storage device.

14. A method according to claim 9, wherein the energy received by the internal energy receiver is stabilized by a capacitor, before the energy is supplied directly or indirectly to the medical device.

15. A method according to claim 9, wherein the difference between the total amount of energy received by the internal energy receiver and the total amount of consumed and/or stored energy is directly or indirectly measured over time, and the energy balance is determined based on a detected change in said total amount difference.

16. A method according to claim 9, wherein the energy received by the internal energy receiver is accumulated and stabilized in an energy stabilizing unit, before the energy is supplied to the medical device.

17. A method according to claim 16, wherein the energy balance is determined based on a detected change followed over time in the amount of consumed and/or stored energy.

18. A method according to claim 17, wherein the change in the amount of consumed and/or stored energy is detected by determining over time the derivative of a measured electrical parameter related to said amount of consumed and/or stored energy, the derivative at a first given moment is corresponding to the rate of the change at the first given moment, wherein the rate of change includes the direction and speed of the change.

19. A method according to claim 18, wherein said derivative is determined based on a detected rate of change of the electrical parameter.

20. A method according to claim 9, wherein the energy received by the internal energy receiver is supplied to the medical device with at least one constant voltage, wherein the constant voltage is created by a constant voltage circuitry.

21-268. -268. (canceled)