Catheters comprising a plurality of oscillators and methods for their use

• US 6,228,046 B1
• Filed: 03/03/1998
• Issued: 05/08/2001
• Est. Priority Date: 06/02/1997
• Status: Expired due to Fees

• Current Assignee: PharmaSonics, Inc.
• Original Assignee: PharmaSonics, Inc.
• Inventors: Brisken, Axel F.
• Primary Examiner(s): Kennedy, Sharon
• Assistant Examiner(s): Hayes, Michael J.
• Application Number:
  US09/033,834
• Time in Patent Office: 1,162 Days
• Field of Search: 604/19, 604/22, 606/169, 606/171, 600/466, 600/467, 600/471
• US Class Current: 604/22
• 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 17/2202 the ultrasound transducer being inside patient's body at the distal end of the catheter
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2017/22051 with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation A61B2017/22048, A61B2017/3486 take precedence
• CPC Class Codes: A61B 2017/22072 with an instrument channel, e.g. for replacing one instrument by the other
• CPC Class Codes: A61B 2017/22082 after introduction of a substance

Abstract

A catheter comprises a catheter body having a vibrational transducer disposed at or near its distal end. The vibrational transducer comprises a plurality of oscillators such as bending plate oscillators or other conventional oscillators each having a vibrational surface capable of imparting pressure waves. The plurality of oscillators may be disposed at a distal end of the catheter body or may alternatively be disposed within the catheter body. The catheter may further comprise lumens for drug delivery, balloons for encircling the transducer structures, or the like. The catheters are useful in a variety of lumenal therapeutic procedures, including drug delivery, stenotic disruption within blood vessel, and the like.

Claims

1. A catheter comprising:

a catheter body having a proximal end, a distal end, and a longitudinal axis;

at least two bending oscillators coupled to a distal end of the catheter body, wherein each of said oscillators has at least one vibrational surface disposed to cooperatively input energy laterally inwardly to a an interior volume therebetween.

2. A catheter as in claim 1 wherein the oscillators are adapted to vibrate the vibrational surfaces at ultrasonic frequencies.

3. A catheter as in claim 1 wherein said vibrational surfaces of each of said at least two oscillators are disposed in a pattern wherein the surfaces are generally parallel to a longitudinal axis of the catheter.

4. A catheter as in claim 1 wherein said plurality of vibrational surfaces are disposed in a pattern wherein the surfaces are generally symmetric about a longitudinal axis of the catheter.

5. A catheter as in claim 1 wherein said plurality of oscillators have vibrational surfaces opposed to one another along a longitudinal axis of said catheter.

6. A catheter as in claim 1, wherein said oscillators comprise at least one active layer which oscillates axially and transversely when energized and at least one opposed layer which constrains or oscillates non-synchronously relative to the active layer, wherein the relative axial and transverse displacement of the active and opposed layers causes transverse flexing of the oscillator.

7. A catheter as in claim 6, wherein the active layer comprises a piezoelectric material.

8. A catheter as in claim 1 wherein each of the plurality of vibrational surfaces are located within 1.0 μ

m.

9. A catheter as in claim 8, wherein each of the plurality of vibrational surfaces are located within 10 μ

m to 100 μ

m.

10. A catheter as in claim 1, wherein the oscillators project distally from the distal end of the catheter body.

11. A catheter as in claim 1 wherein the catheter body has a lumen extending from the proximal end to a point near the oscillators.

12. A catheter as in claim 11, wherein said lumen has a distal end between the vibratory surfaces.

13. A catheter as in claim 1 further comprising a fluid injection lumen and a fluid suction lumen, said lumens having orifices located near the distal end of the catheter body.

14. A method for intraluminal delivery of vibrational energy to a body lumen comprising the steps of:

providing a catheter having at least two bending oscillators on a distal end of the catheter, said oscillators each having a vibrational surface;

positioning said catheter adjacent a target site within the patient; and

energizing said plurality of oscillators to cooperatively vibrate at least two vibrational surfaces to input energy laterally and inwardly into the target site or fluid.

15. A method of claim 14 wherein the energizing step comprises vibrating said vibrational surfaces out of phase.

16. A method as in claim 14, wherein said vibrational surfaces vibrate at a frequency in the range from 1000 Hz to 40000 Hz.

17. A method as in claim 14, further comprising releasing a therapeutic agent at the target site.

18. A method as in claim 17 wherein the agent is released via a lumen in the catheter.

19. A method as in claim 17, wherein the therapeutic agent is released prior to energizing the plurality of oscillators.

20. A method as in claim 17, wherein the therapeutic agent is released while energizing the oscillators.