Ultrasonic medical device

• US 6,277,084 B1
• Filed: 05/05/1997
• Issued: 08/21/2001
• Est. Priority Date: 03/31/1992
• Status: Expired due to Fees

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Corporation
• Inventors: Heath, Kevin R., Abele, John E.
• Primary Examiner(s): Casler, Brian L.
• Application Number:
  US08/851,163
• Time in Patent Office: 1,569 Days
• Field of Search: 606/127, 606/31, 606/27, 606/171, 606/159, 606/169, 606/128, 600/585, 600/461, 607/96, 604/22, 601/2, 428/364, 428/375, 428/378, 428/379, 428/386, 428/389, 428/397, 295/921, 297/29, 297/58, 292/70
• US Class Current: 601/2
• CPC Class Codes: A61B 17/22012 in direct contact with, or very close to, the obstruction or concrement for removing obstructions in blood vessels by laser A61B18/245
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61F 2002/3008 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0019 operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61L 31/022 Metals or alloys
• CPC Class Codes: A61L 31/088 Other specific inorganic materials not covered by A61L31/084 or A61L31/086
• CPC Class Codes: A61L 31/18 Materials at least partially X-ray or laser opaque
• CPC Class Codes: A61M 2025/09166 having radio-opaque features
• CPC Class Codes: A61M 25/0108 using radio-opaque or ultrasound markers
• CPC Class Codes: Y10T 29/53909 Means comprising hand manipulatable tool

Abstract

Wires are used for conducting ultrasound energy. These wires achieve optimum properties by creating a multiple material coaxial construction. For example, in a particular embodiment it is desirable to have an elastic core (nitinol) for conducting axial vibrations (sonic or ultrasonic) and a thin stiff cladding (stainless steel) in order to minimize traverse vibrations which result in loss of energy.

Claims

1. An ultrasound medical device comprising:

a source of ultrasound energy, and an elongated wire-form for transmission of ultrasound energy, said wire-form having a proximal portion, a distal portion, and a length therebetween, said wire-form including along its length a sheath surrounding and contacting a metal core where said sheath and said metal core are formed of different materials, wherein said core and said sheath are bonded at points where said core contacts said sheath.

2. The medical device of claim 1 wherein the wire-form is a draw-form.

3. The medical device of claim 1 wherein said sheath and core are constructed of materials of substantially different ultrasound impedance.

4. The medical device of claim 1 wherein said core and said sheath are different metals.

5. The medical device of claim 1 including air pockets disposed between said points where said core is bonded to said sheath.

6. The medical device of claim 1 wherein said core has a circular cross-section.

7. The medical device of claim 1 wherein said source of ultrasound energy provides axial excitation.

8. The medical device of claim 1 wherein said source of ultrasound energy is coupled to said core.

9. The medical device of claim 1 wherein said source of ultrasound energy and said wire-form are arranged for ablation of tissue.

10. The ultrasound medical device of claim 1, wherein said sheath is formed of nitinol and said core is formed of titanium.

11. The ultrasound medical device of claim 1, wherein said sheath is formed of stainless steel and said core is formed of a nitinol.

12. The ultrasound medical device of claim 1, wherein said sheath is formed of a non-metal.

13. The ultrasound medical device of claim 1, wherein said core is formed of tantalum.

14. The ultrasound medical device of claim 1, wherein said sheath is formed of a nitinol and said core is formed of tantalum.

15. A method of transmitting ultrasound energy into the body comprising:

providing a source of ultrasound energy,

coupling said source of ultrasound energy to an elongated wire-form for use within the body, said wire-form having a proximal portion, distal portion, and a length therebetween, said wire-form including along its length a sheath surrounding and contacting a metal core where said sheath and said core are formed of different materials, said core and sheath being bonded at intermittent points corresponding to points where said core contacts said sheath,

generating ultrasound energy with said source of ultrasound energy, and

transmitting said ultrasound energy along said length of said wire form.

16. The method of claim 15 comprising transmitting said ultrasound energy from the proximal end to the distal end and utilizing said ultrasound energy at the distal end to treat tissue.

17. The method of claim 16 comprising coupling said source of ultrasound energy to said core.

18. The method of claim 15 comprising ablating tissue with said ultrasound energy.

19. The method of claim 15 comprising relaxing tissue with said ultrasound energy.

20. The method of claim 15 comprising enhancing delivery of drug with said ultrasound energy.

21. The method of claim 15 wherein said wire-form is a draw-form.

22. The method of claim 15 wherein said sheath and core are constructed of materials of substantially different ultrasound impedance.

23. The method of claim 15 wherein said core and said sheath are different metals.

24. The method of claim 15 including air pockets disposed between said points where said sheath is bonded to said core.

25. The method of claim 15 wherein said core has a circular cross-section.

26. The method of claim 15 wherein said source of ultrasound energy provides axial excitation.

27. The method of claim 15, wherein said sheath is formed of nitinol and said core is formed of titanium.

28. The method of claim 15, wherein said sheath is formed of stainless steel and said core is formed of a nitinol.

29. The method of claim 15, wherein said sheath is formed of a non-metal.

30. The method of claim 15, wherein said core is formed of tantalum.

31. The method of claim 15, wherein said sheath is formed of a nitinol and said core is formed of tantalum.

32. A method for making an ultrasound medical device comprising:

providing a draw-form wire with a first material forming a sheath surrounding and contacting a second metal forming a core different than the first metal, said core and sheath being bonded at intermittent points corresponding to points where said core contacts said sheath,

providing a source of ultrasound energy, and

coupling said draw-form wire to said source of ultrasound energy.

33. The medical device of claim 32 wherein said sheath and core are constructed of materials of substantially different ultrasound impedance.

34. The method of claim 32 comprising coupling said source of ultrasound energy to said core.

35. The method of claim 32 including air pockets disposed between said points where said sheath is bonded to said core.

36. The method of claim 32 wherein said core has a circular cross-section.

37. The method of claim 32 wherein said source of ultrasound energy provides axial excitation.

38. The method of claim 32, wherein said sheath is formed of a nitinol and said core is formed of titanium.

39. The method of claim 32, wherein said sheath is formed of stainless steel and said core is formed of a nitinol.

40. The method of claim 32, wherein said sheath is formed of a non-metal.

41. The method of claim 32, wherein said core is formed of tantalum.

42. The method of claim 32, wherein said sheath is formed of nitinol and said core is formed of tantalum.

43. The method of claim 32 comprising transmitting said energy from a proximal end of the draw-form wire to a distal end of the draw-form wire and utilizing said energy at the distal end to treat tissue.