External charger with adjustable alignment indicator

• US 10,010,717 B2
• Filed: 01/04/2016
• Issued: 07/03/2018
• Est. Priority Date: 12/03/2008
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Inventors: Aghassian, Daniel, Freidin, Lev, Chen, Joey
• Primary Examiner(s): Manuel, George
• Application Number:
  US14/986,874
• Publication Number:
  US 20160114173A1
• Time in Patent Office: 911 Days
• Field of Search: 607 60, 607 61, 607 46, 607 33
• CPC Class Codes: A61B 2018/205545 Arrangements for particular spot shape, e.g. square or annular
• CPC Class Codes: A61N 1/37235 Aspects of the external programmer
• CPC Class Codes: A61N 1/37252 Details of algorithms or data aspects of communication system, e.g. handshaking, transmitting specific data or segmenting data
• CPC Class Codes: A61N 1/37258 Alerting the patient
• CPC Class Codes: A61N 1/37276 characterised by means for reducing power consumption during telemetry
• 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 50/12 of the resonant type
• 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 50/90 involving detection or optimisation of position, e.g. alignment
• 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: H02J 7/0044 specially adapted for holding portable devices containing batteries H02J7/0045 takes precedence

Abstract

Electrical energy is transcutaneously transmitted at a plurality of different frequencies to an implanted medical device. The magnitude of the transmitted electrical energy respectively measured at the plurality of frequencies. One of the frequencies is selected based on the measured magnitude of the electrical energy (e.g., the frequency at which the measured magnitude of the electrical energy is the greatest). A depth level at which the medical device is implanted within the patient is determined based on the selected frequency. For example, the depth level may be determined to be relatively shallow if the selected frequency is relatively high, and relatively deep if the selected frequency is relative low. A charge strength threshold at which a charge strength indicator generates a user-discernible signal can then be set based on the determined depth level.

Claims

1. An external charger for an implantable medical device, comprising:

a coil configured to generate a magnetic field to provide power to the implantable medical device;

an indicator configured to indicate to a user alignment of the external charger to the implantable medical device in accordance with a threshold;

control circuitry, wherein the control circuitry is configured to drive the coil at a plurality of different frequencies within a frequency range to generate the magnetic field; and

a detector configured to measure a magnitude of a current of the coil at each of the plurality of frequencies,

wherein the control circuitry is further configured to;

select a frequency using the measured current magnitudes, and

select the threshold for use by the indicator using the selected frequency.

2. The external charger of claim 1, wherein the control circuitry is configured to select the frequency at which the measured current magnitude is greatest.

3. The external charger of claim 1, wherein the control circuitry comprises a processor.

4. The external charger of claim 1, wherein the control circuitry further comprises a memory, wherein the memory comprises data correlating frequencies with threshold values.

5. The external charger of claim 4, wherein the control circuitry is configured to select the threshold by comparing the selected frequency to the data correlating frequencies with threshold values.

6. The external charger of claim 5, wherein comparing the selected frequency to the data correlating frequencies with threshold values comprises selecting a threshold value as the threshold using the selected frequency.

7. The external charger of claim 1, further comprising a memory, wherein the selected threshold for use by the indicator is stored in the memory.

8. The external charger of claim 1, wherein the indicator comprises an audio transducer configured to produce an audible alignment indication.

9. The external charger of claim 1, wherein the indicator comprises a visual indicator configured to produce a visual alignment indication.

10. The external charger of claim 1, wherein the indicator indicates an extent of a charge rate of the implantable medical device.

11. The external charger of claim 1, further comprising a battery for providing power to generate the magnetic field.

12. The external charger of claim 1, wherein selected threshold increases as the selected frequency decreases, and wherein the selected threshold decreases as the selected frequency increases.

13. The external charger of claim 1, wherein the control circuitry is further configured to determine a depth at which the implantable medical device is implanted within a patient based on the selected frequency.

14. The external charger of claim 13, wherein the determined depth increases as the selected frequency decreases, and wherein the determined depth decreases as the selected frequency increases.

15. The external charger of claim 13, further comprising a memory, wherein data correlating frequencies with depth values is stored in the memory.

16. The external charger of claim 1, further comprising a portable housing for the coil, the indicator, the control circuitry, and the detector.

17. The external charger of claim 1, further comprising a portable housing for the indicator, the control circuitry, and the detector, wherein the coil is connected to the housing by a cable.

18. The external charger of claim 1, wherein the control circuitry comprises a controllable oscillator to sweep the frequency at which the coil is driven.