ULTRASONIC TRANSDUCER FOR A METALLIC CAVITY IMPLANTED MEDICAL DEVICE

• US 20110190669A1
• Filed: 04/08/2011
• Published: 08/04/2011
• Est. Priority Date: 07/21/2006
• Status: Active Grant

• Current Assignee: Abhijeet V. Chavan, Bin Mi, Keith R Maile
• Original Assignee: Abhijeet V. Chavan, Bin Mi, Keith R Maile
• Inventors: Chavan, Abhijeet V., Maile, Keith R., Mi, Bin
• Granted Patent: US 8,548,592 B2
• Time in Patent Office: Days
• US Class Current: 601/2
• CPC Class Codes: A61B 5/0028 Body tissue as transmission medium, i.e. transmission systems where the medium is the human body
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/37288 Communication to several implantable medical devices within one patient

Abstract

Implantable medical devices including an ultrasonic transducer and methods of optimizing an ultrasonic transducer of an implantable medical device are disclosed. The implantable medical device can include a housing, an ultrasonic transducer disposed within an interior of the housing, and a limiting structure configured to constrain deformation of the ultrasonic transducer. The limiting structure can include a separate structure coupled to the housing, or can comprise a resonant portion of the housing itself. During operation, the ultrasonic transducer is configured to communicate at a frequency at or near a resonant frequency of the housing.

Claims

1. An implantable medical device, comprising:

a housing;

an ultrasonic transducer disposed within an interior of the housing, the ultrasonic transducer configured to communicate at a frequency at or near a resonance frequency of the housing; and

a limiting structure configured to constrain deformation of the ultrasonic transducer.

2. The implantable medical device of claim 1, wherein the limiting structure comprises an annular-shaped structure.

3. The implantable medical device of claim 1, wherein the limiting structure comprises a corner of the housing.

4. The implantable medical device of claim 1, wherein the limiting structure comprises a header coupled to the housing.

5. The implantable medical device of claim 4, further comprising an aperture located in the header, and wherein the ultrasonic transducer extends into a resonant region defined by the aperture.

6. The implantable medical device of claim 1, wherein the ultrasonic transducer is secured to the housing and extends from the limiting structure to a resonant region of the housing.

7. The implantable medical device of claim 1, wherein the limiting structure extends to a rear wall of the housing.

8. The implantable medical device of claim 1, wherein the limiting structure is located inside the housing.

9. The implantable medical device of claim 1, wherein the limiting structure is located outside of the housing.

10. The implantable medical device of claim 1, wherein the limiting structure is a non-active limiting structure.

11. The implantable medical device of claim 1, further comprising a casing coupled to the housing and disposed over the ultrasonic transducer, wherein the casing is adapted to amplify the deformation of the ultrasonic transducer in a bending mode and transfer the bending moment to the housing.

12. An implantable medical device, comprising:

a housing; and

an ultrasonic transducer disposed over an undulating portion of the housing, the ultrasonic transducer configured to communicate at a frequency at or near a resonance frequency of the housing.

13. The implantable medical device of claim 12, wherein the undulating portion comprises a thinned region of the housing having a thinner cross-section than a substantial portion of the housing.

14. The implantable medical device of claim 13, wherein the thinned region is annular shaped.

15. The implantable medical device of claim 12, wherein the undulating portion comprises a wavy or corrugated portion of the housing.

16. The implantable medical device of claim 12, further comprising a gas-filled gap or vacuum disposed between the ultrasonic transducer and the undulating portion of the housing.

17. The implantable medical device of claim 12, further comprising a casing coupled to the housing and disposed over the ultrasonic transducer, wherein the casing is adapted to amplify the deformation of the ultrasonic transducer in a bending mode and transfer the bending moment to the housing.

18. A method of optimizing an ultrasonic transducer and a housing of an implantable medical device, the method comprising:

determining system level requirements for the ultrasonic transducer;

selecting an initial ultrasonic transducer based on the system level requirements;

conducting a first finite element methods analysis to verify the feasibility of the initial ultrasonic transducer;

conducting a second finite element methods analysis and water tank experiments to determine whether the housing and ultrasonic transducer have a desired vibration mode at a targeted ultrasonic communication frequency;

optimizing the ultrasonic transducer or the design of the housing based on the results of the first and second finite element methods analysis and water tank experiments;

verifying a resonance frequency and amplitude of the optimized ultrasonic transducer using finite element method analysis and water tank experiments; and

selecting a final ultrasonic transducer and housing design based upon the results of the verifying step.

19. The method of claim 18, wherein the conducting a second finite element analysis and water tank experiments step includes at least one of the steps of conducting water tank experiments and scanning laser vibrometer (SLV) measurements.

20. The method of claim 18, wherein the verifying step includes at least one of the steps of conducting water tank experiments and scanning laser vibrometer (SLV) measurements.