SYSTEMS AND METHODS OF MONITORING THE ACOUSTIC COUPLING OF MEDICAL DEVICES

• US 20090326609A1
• Filed: 04/21/2009
• Published: 12/31/2009
• Est. Priority Date: 06/27/2008
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Doron, Eyal
• Granted Patent: US 8,798,761 B2
• Time in Patent Office: Days
• US Class Current: 607/60
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/6843 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61B 8/4281 characterised by sound-transmitting media or devices for coupling the transducer to the tissue
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile

Abstract

Systems and methods for monitoring the acoustic coupling of medical devices is disclosed. An illustrative system for monitoring the acoustic coupling of an acoustic transducer attached to a patient'"'"'s body includes a signal generator adapted to supply an electrical signal to the transducer, a circuit configured to measure at least one electrical parameter of the transducer, and a processor adapted to evaluate the degree of acoustic coupling of the transducer to the body based on the measured electrical signal. The processor can measure the frequency response of the acoustic transducer to the electrical signal, a time domain response of the acoustic transducer to the electrical signal, or a combination of both.

Claims

1. A system for monitoring the acoustic coupling of an acoustic transducer attached to a patient'"'"'s body, comprising:

an acoustic transducer attachable to the body and in acoustic communication with an implantable medical device;

a signal generator coupled to the acoustic transducer, the signal generator adapted to supply an electrical signal to the acoustic transducer for generating an acoustic wave;

a circuit configured to measure at least one electrical parameter of the acoustic transducer in response to the electrical signal; and

an evaluation module adapted to evaluate the degree of acoustic coupling of the transducer to the body based at least in part on the measured electrical parameter.

2. The system of claim 1, wherein the evaluation module is configured to evaluate an impedance parameter associated with the acoustic transducer.

3. The system of claim 2, wherein the impedance parameter includes a measured voltage or current parameter.

4. The system of claim 2, wherein the impedance parameter includes a frequency parameter of the electrical signal supplied to the acoustic transducer.

5. The system of claim 1, wherein the evaluation module is configured to evaluate the acoustic coupling by sweeping a frequency range and, at a plurality of frequencies, measuring a corresponding impedance parameter at each frequency.

6. The system of claim 1, wherein the circuit comprises a time domain coupling circuit.

7. The system of claim 6, wherein the evaluation module is configured to evaluate the acoustic coupling based on a time domain parameter associated with the acoustic transducer.

8. The system of claim 6, wherein the evaluation module is configured to evaluate the acoustic coupling based on a time-domain parameter and a frequency parameter associated within the acoustic transducer.

9. A method of monitoring the acoustic coupling of an acoustic transducer attached to a patient'"'"'s body, comprising:

providing an electrical signal to the acoustic transducer;

measuring at least one electrical parameter associated with the response of the acoustic transducer to the electrical signal; and

evaluating the degree of acoustic coupling of the acoustic transducer to the body based at least in part on the at least one measured electrical parameter.

10. The method of claim 9, wherein providing an electric signal to the acoustic transducer includes sweeping a frequency range, and wherein evaluating the degree of acoustic coupling of the transducer to the body includes measuring an impedance parameter at a plurality of frequencies.

11. The method of claim 9, wherein measuring at least one electrical parameter includes measuring an impedance parameter associated within the acoustic transducer in response to the electrical signal.

12. The method of claim 9, wherein the at least one electrical parameter includes a voltage parameter associated with the acoustic transducer.

13. The method of claim 9, wherein the at least one electrical parameter includes a current parameter associated with the acoustic transducer.

14. The method of claim 9, wherein the at least one electrical parameter includes a frequency parameter associated with the acoustic transducer.

15. The method of claim 9, further comprising outputting a warning signal if the degree of acoustic coupling falls below a threshold coupling value.

16. The method of claim 9, wherein evaluating the degree of acoustic coupling of the acoustic transducer to the body based at least in part on the at least one measured electrical parameter includes measuring a time domain parameter associated with the response of the acoustic transducer to the electrical signal.

17. The method of claim 9, wherein evaluating the degree of acoustic coupling of the acoustic transducer to the body based at least in part on the at least one measured electrical parameter includes measuring a frequency parameter associated with the response of the acoustic transducer to the electrical signal.

18. The method of claim 9, wherein evaluating the degree of acoustic coupling of the acoustic transducer to the body based at least in part on the at least one measured electrical parameter includes measuring both a frequency parameter and a time domain parameter associated with the response of the acoustic transducer to the electrical signal.

19. The method of claim 9, wherein evaluating the degree of acoustic coupling of the acoustic transducer to the body based at least in part on the at least one measured electrical parameter includes measuring the load resistance or mechanical inductance of an equivalence electrical circuit modeling the acoustic transducer.

20. A method of monitoring the acoustic coupling of an acoustic transducer attached to a patient'"'"'s body, comprising:

providing a time-varying electrical signal to an acoustic transducer having a number of terminal leads;

measuring the voltage at the terminal leads in response to the electrical signal;

measuring the current across the terminal leads in response to the electrical signal; and

evaluating the degree of acoustic coupling of the acoustic transducer to the body based at least in part on the measured voltage and current.