Catheter with multiple transducers

• US 6,585,656 B2
• Filed: 02/05/2002
• Issued: 07/01/2003
• Est. Priority Date: 02/07/2000
• Status: Expired due to Fees

• Current Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Masters, Donald
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): Imam, Ali M.
• Application Number:
  US10/072,186
• Publication Number:
  US 20020072669A1
• Time in Patent Office: 511 Days
• Field of Search: 600/443-447, 600/459, 600/462, 600/463, 600/466, 600/467, 736/25, 736/33, 736/26, 607/97
• US Class Current: 600/466
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61B 8/4461 Features of the scanning mechanism, e.g. for moving the transducer within the housing of the probe

Abstract

A diagnostic and/or therapeutic catheter having a plurality of ultrasound transducers. In a first embodiment, the center frequencies of the second and third transducers may be substantially equal to a fundamental harmonic and a second harmonic, respectively, of ultrasound waves created by the first transducer. In second embodiment, the second transducer transmits waves with a center frequency substantially equal to the center frequency of the first transducer. In third embodiment, the second transducer has a center frequency that differs from the center frequency of the first transducer and the center frequency of the third transducer may be substantially equal to a difference between the fundamental harmonic of the ultrasound waves transmitted by the first transducer and a fundamental harmonic of ultrasound waves produced by the second transducer.

Claims

1. A medical device for a medical imaging system, the medical device comprising:

an elongate body adapted to be inserted into a patient'"'"'s body;

a drive shaft being substantially within the elongate body and having a proximal end portion and a distal end portion, the proximal end portion adapted to communicate with the medical imaging system;

a first imaging device adapted to transmit energy and has a center frequency, the first imaging device being mounted on or near the distal end portion of the drive shaft;

a second imaging device adapted to receive a reflection of the energy transmitted by the first imaging device, the second imaging device being mounted on or near the distal end portion of the drive shaft at a distance from the first imaging device and having a center frequency substantially equal to a fundamental harmonic of the energy transmitted by the first imaging device; and

a third imaging device adapted to receive a reflection of the energy transmitted by the first imaging device, the third imaging device being mounted on or near the distal end portion of the drive shaft at a distance from the first imaging device and having a center frequency substantially equal to a second harmonic of the energy transmitted by the first imaging device.

2. The medical device of claim 1, wherein the proximal end portion of the drive shaft rotatably communicates with the medical imaging system.

3. The medical device of claim 1, wherein the preselected distance between the first imaging device and the second imaging device is less than the preselected distance between the first imaging device and the third imaging device.

4. The medical device of claim 1, wherein the second imaging device is disposed between the first imaging device and the third imaging device.

5. The medical device of claim 1, wherein the first imaging device is fixedly mounted on the distal end portion of the drive shaft.

6. The medical device of claim 1, wherein the first imaging device is adjustably mounted on the distal end portion of the drive shaft.

7. The medical device of claim 6, wherein the first imaging device has a first steering device.

8. The medical device of claim 7, wherein the first steering device comprises a piezoelectric steering device.

9. The medical device of claim 7, wherein the first steering device comprises an electric-field steering device.

10. The medical device of claim 1, wherein the second imaging device is fixedly mounted on the distal end portion of the drive shaft.

11. The medical device of claim 1, wherein the second imaging device is adjustably mounted on the distal end portion of the drive shaft.

12. The medical device of claim 11, wherein the second imaging device has a second steering device.

13. The medical device of claim 12, wherein the second steering device comprises a piezoelectric steering device.

14. The medical device of claim 12, wherein the second steering device comprises an electric-field steering device.

15. The medical device of claim 1, wherein the third imaging device is fixedly mounted on the distal end portion of the drive shaft.

16. The medical device of claim 1, wherein the first imaging device, the second imaging device, and the third imaging device each have a substantially uniform thickness.

17. The medical device of claim 1 wherein the first imaging device comprises an ultrasound transducer adapted to transmit the energy in the form of ultrasound waves.

18. The medical device of claim 17 wherein the second imaging device comprises an ultrasound transducer adapted to receive the reflection of the energy in the form of ultrasound waves.

19. The medical device of claim 18 wherein the third imaging device comprises an ultrasound transducer adapted to receive the reflection of the energy in the form of ultrasound waves.

20. The medical device of claim 17, further comprising a backing layer for absorbing energy radiating from a back surface of the first imaging device, the backing layer coupled to the back surface of the first imaging device.

21. The medical device of claim 20, wherein the backing layer is formed from a high impedance material.

22. The medical device of claim 1, wherein the first imaging device is substantially flat.

23. The medical device of claim 1, wherein the first imaging device is substantially concave.

24. The medical device of claim 1, wherein the first imaging device is substantially convex.

25. The medical device of claim 1, wherein the medical device is a catheter and the elongate body includes a catheter body.

26. A medical device for a medical imaging system, the medical device comprising:

an elongate body adapted to be inserted into a patient'"'"'s body;

a drive shaft being substantially within the elongate body and having a proximal end portion and a distal end portion, the proximal end portion adapted to communicate with the medical imaging system;

a first imaging device adapted to transmit energy and has a center frequency, the first imaging device being mounted on or near the distal end portion of the drive shaft; and

a second imaging device adapted to transmit energy, the second imaging device being mounted on or near the distal end portion of the drive shaft at a preselected distance from the first imaging device and having a center frequency substantially equal to the center frequency of the first imaging device.

27. The medical device of claim 26, wherein the energy transmitted by the first imaging device and the energy transmitted by the second imaging device substantially diverge.

28. The medical device of claim 27, wherein the first imaging device is directed toward a first end of a tissue segment, and wherein the second imaging device is directed toward a second end of the tissue segment.

29. The medical device of claim 26, wherein the proximal end portion of the drive shaft rotatably communicates with the medical imaging system.

30. The medical device of claim 26, wherein the first imaging device is fixedly mounted on the distal end portion of the drive shaft.

31. The medical device of claim 26, wherein the first imaging device is adjustably mounted on the distal end portion of the drive shaft.

32. The medical device of claim 31, wherein the first imaging device has a first steering device.

33. The medical device of claim 32, wherein the first steering device comprises a piezoelectric steering device.

34. The medical device of claim 32, wherein the first steering device comprises an electric-field steering device.

35. The medical device of claim 26, wherein the second imaging device is fixedly mounted on the distal end portion of the drive shaft.

36. The medical device of claim 26, wherein the second imaging device is adjustably mounted on the distal end portion of the drive shaft.

37. The medical device of claim 36, wherein the second imaging device has a second steering device.

38. The medical device of claim 37, wherein the second steering device comprises a piezoelectric steering device.

39. The medical device of claim 37, wherein the second steering device comprises an electric-field steering device.

40. The medical device of claim 26, wherein the first imaging device and the second imaging device each have a substantially uniform thickness.

41. The medical device of claim 26, wherein the first imaging device includes an ultrasound transducer adapted to transmit the energy in the form of ultrasound waves.

42. The medical device of claim 41, further comprising a backing layer for absorbing energy radiating from a back surface of the first imaging device, the backing layer coupled to the back surface of the first imaging device.

43. The medical device of claim 42, wherein the backing layer is formed from a high impedance material.

44. The medical device of claim 26, wherein the first imaging device is substantially flat.

45. The medical device of claim 26, wherein the first imaging device is substantially concave.

46. The medical device of claim 26, wherein the first imaging device is substantially convex.

47. The medical device of claim 41, wherein the second imaging device includes an ultrasound transducer adapted to transmit the energy in the form of ultrasound waves.

48. The medical device of claim 47, further comprising a backing layer for absorbing energy radiating from a back surface of the second imaging device, the backing layer coupled to the back surface of the second imaging device.

49. The medical device of claim 48, wherein the backing layer is formed from a high impedance material.

50. The medical device of claim 26, wherein the second imaging device is substantially flat.

51. The medical device of claim 26, wherein the second imaging device is substantially concave.

52. The medical device of claim 26, wherein the second imaging device is substantially convex.

53. The medical device of claim 26, wherein the medical device is a catheter and the elongate body includes a catheter body.

54. A medical device for a medical imaging system, the medical device comprising:

a drive shaft having a proximal end portion and a distal end portion, the proximal end portion adapted to communicate with the medical imaging system;

a first imaging device adapted to transmit energy and has a center frequency, the first imaging device being mounted on or near the distal end portion of the drive shaft; and

a second imaging device adapted to transmit and receive energy, the second imaging device being mounted on or near the distal end portion of the drive shaft at a distance from the first imaging device and having a center frequency differing from the center frequency of the first imaging device, the energy transmitted by the second imaging device substantially converging with the energy transmitted by the first imaging device and forming a difference energy having a fundamental harmonic substantially equal to a difference between a fundamental harmonic of the energy transmitted by the first imaging device and a fundamental harmonic of the energy transmitted by the second imaging device.

55. The medical device of claim 54 further comprising a third imaging device adapted to receive energy, the third imaging device being mounted on or near the distal end portion of the drive shaft at a distance from the first imaging device and having a center frequency substantially equal to a difference between the fundamental harmonic of the energy transmitted by the first imaging device and the fundamental harmonic of the energy transmitted by the second imaging device, and being directed to receive a reflection of the difference energy.

56. The medical device of claim 54, wherein the proximal end portion of the drive shaft rotatably communicates with the medical imaging system.

57. The medical device of claim 54, wherein the distance between the first imaging device and the second imaging device is less than the distance between the first imaging device and the third imaging device.

58. The medical device of claim 54, wherein the second imaging device is disposed between the first imaging device and the third imaging device.

59. The medical device of claim 54, wherein the energy transmitted by the first imaging device and the energy transmitted by the second imaging device substantially converge at a preselected distance from the drive shaft.

60. The medical device of claim 59, wherein the first imaging device has a first steering device for controlling a distance from the drive shaft at which the energy transmitted by the first imaging device and the energy transmitted by the second imaging device substantially converge.

61. The medical device of claim 60, wherein the first steering device comprises a piezoelectric steering device.

62. The medical device of claim 60, wherein the first steering device comprises an electric-field steering device.

63. The medical device of claim 62, wherein the second imaging device has a second steering device for controlling a distance from the drive shaft at which the energy transmitted by the first imaging device and the energy transmitted by the second imaging device substantially converge.

64. The medical device of claim 63, wherein the second steering device comprises a piezoelectric steering device.

65. The medical device of claim 63, wherein the second steering device comprises an electric-field steering device.

66. The medical device of claim 55, wherein the first imaging device and the second imaging device each are excited by a signal having a fixed frequency.

67. The medical device of claim 66, wherein the frequency of the energy transmitted by the first imaging device is 35.100 MHz, the frequency of the energy transmitted and received by the second imaging device is 35.000 MHz, and the frequency of the energy received by the third imaging device is 100 KHz.

68. The medical device of claim 54, wherein the first imaging device and the second imaging device each are excited by a signal sweeping through a range of frequencies, a difference between a fundamental harmonic of the energy transmitted by the first imaging device and a fundamental harmonic of the energy transmitted by the second imaging device being substantially constant.

69. The medical device of claim 68, wherein the difference between the fundamental harmonic of the energy transmitted by the first imaging device and the fundamental harmonic of the energy transmitted by the second imaging device is substantially equal to 100 KHz.

70. A method of manufacturing a medical device for a medical imaging system, the method comprising:

providing an elongate body and a drive shaft disposed at least partially in the elongate body, the drive shaft having a proximal end portion and a distal end portion, the proximal end portion adapted to communicate with the medical imaging system;

mounting a first imaging device adapted to transmit energy on or near the distal end portion of the drive shaft and having a center frequency;

mounting a second imaging device adapted to receive energy on or near the distal end portion of the drive shaft at a distance from the first imaging device and having a center frequency substantially equal to a fundamental harmonic of the energy transmitted by the first imaging device; and

mounting a third imaging device adapted to receive energy on or near the distal end portion of the drive shaft at a distance from the first imaging device and having a center frequency substantially equal to a second harmonic of the energy transmitted by the first imaging device.

71. A method of manufacturing a medical device for a medical imaging system, the method comprising:

providing an elongate body and a drive shaft disposed at least partially in the elongate body, the drive shaft having a proximal end portion and a distal end portion, the proximal end portion adapted to communicate with the medical imaging system;

mounting a first imaging device adapted to transmit energy on or near the distal end of the drive shaft and having a center frequency; and

mounting a second imaging device adapted to transmit energy on or near the distal end of the drive shaft at a distance from the first imaging device and having a center frequency substantially equal to the center frequency of the first imaging device.

72. A method of manufacturing a medical device for a medical imaging system, the method comprising:

providing an elongate body and a drive shaft disposed at least partially in the elongate body, the drive shaft having a proximal end portion and a distal end portion, the proximal end portion adapted to communicate with the medical imaging system;

mounting a first imaging device adapted to transmit energy on or near the distal end portion of the drive shaft and having a center frequency;

mounting a second imaging device adapted to transmit and receive energy on or near the distal end portion of the drive shaft at a distance from the first imaging device and having a center frequency differing from the center frequency of the center frequency of the first imaging device; and

mounting a third imaging device adapted to receive energy on or near the distal end portion of the drive shaft at a distance from the first imaging device and having a center frequency substantially equal to a difference between a fundamental harmonic of the energy transmitted by the first imaging device and the a fundamental harmonic of the energy transmitted by the second imaging device.