System and method for medical treatment using ultrasound

• US 20050277853A1
• Filed: 06/14/2004
• Published: 12/15/2005
• Est. Priority Date: 06/14/2004
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Inventors: Makin, Inder Raj S., Mast, T. Douglas, Faidi, Waseem, Slayton, Michael H., Barthe, Peter G.
• Granted Patent: US 7,806,839 B2
• Time in Patent Office: Days
• US Class Current: 601/2
• CPC Class Codes: A61N 2007/0065 Concave transducers
• CPC Class Codes: A61N 2007/0078 with multiple treatment transducers
• CPC Class Codes: A61N 2007/0095 by modifying an excitation signal
• CPC Class Codes: A61N 2007/027 with multiple foci created simultaneously
• CPC Class Codes: A61N 7/022 intracavitary

Abstract

A system and method for medical treatment of tissue using ultrasound. The system comprises a probe having an array of transducer elements, an ultrasound waveform generator adapted to generate at least one electrical ultrasound signal, and a plurality of phase controls, each coupled to the ultrasound waveform generator and adapted to generate from the electrical ultrasound signal a phase-shifted drive signal that is coupled to an associated transducer element. The drive signal is effective to control grating lobe foci emitted by the array. The method employs the system.

Claims

1. A system for medical treatment of tissue using ultrasound, comprising:

a probe having an array of transducer elements;

an ultrasound waveform generator adapted to generate at least one electrical ultrasound signal; and

a plurality of phase controls coupled to the ultrasound waveform generator, each phase control adapted to generate from the at least one electrical ultrasound signal a phase-shifted drive signal that is coupled to an associated transducer element, effective to control grating lobe foci emitted by the array.

2. The system of claim 1 wherein each phase control further includes a focusing phase shift portion adapted to electronically focus the array.

3. The system of claim 1 wherein the transducer includes at least one of a substantially linear array, a phased array, a curved array, a geometrically focused transducer, a plurality of single-element transducers having a common drive signal, and a convex transducer.

4. The system of claim 3 wherein the transducer further includes an acoustic lens.

5. The system of claim 1 wherein:

the transducer elements comprise a plurality of groups of elements;

the drive signals coupled to transducer elements within each group are substantially alike in phase shift; and

the drive signals substantially differ in phase shift between groups of elements.

6. The system of claim 1 wherein the phase shifts of the drive signals vary periodically in time.

7. The system of claim 6 wherein the phase shifts of the drive signals vary between a plurality of predetermined states.

8. The system of claim 1 wherein the drive signals are adapted to electronically focus the array at a single location and produce a plurality of grating lobe foci at a predetermined group of locations.

9. The system of claim 8 wherein the drive signals are additionally adapted to produce a plurality of grating lobe foci at a second predetermined group of locations.

10. The system of claim 8 wherein the drive signals are additionally adapted to produce a plurality of grating lobe foci at varying predetermined groups of locations.

11. The system of claim 10 wherein the grating lobe foci are varied at least one of periodically and sequentially.

12. The system of claim 1 wherein the drive signals are adapted to electronically focus the array at variable locations and to produce a plurality of grating lobe foci at a predetermined group of locations.

13. The system of claim 12 wherein the drive signals are additionally adapted to produce a plurality of grating lobe foci at a second predetermined group of locations.

14. The system of claim 12 wherein the drive signals are additionally adapted to produce a plurality of grating lobe foci at varying predetermined groups of locations.

15. The system of claim 12 wherein the grating lobe foci are varied at least one of periodically and sequentially.

16. A system for medical treatment of tissue using ultrasound, comprising:

a probe having an array of transducer elements;

an ultrasound waveform generator adapted to generate at least one electrical ultrasound signal; and

a plurality of phase controls coupled to the ultrasound waveform generator, each phase control adapted to generate from the at least one electrical ultrasound signal a drive signal that is coupled to an associated transducer element, the phase controls comprising;

a focusing phase shift portion adapted to produce a first phase shift in the drive signal, and

a grating lobe phase shift portion adapted to produce a second phase shift in the drive signal, wherein each drive signal has a composite phase shift that is the mathematical sum of the first and second phase shifts, effective to cause the array to emit acoustic ultrasound signals having a focal point controlled by the first phase shift and grating lobe foci controlled by the second phase shift.

17. The system of claim 16 wherein the transducer includes at least one of a substantially linear array, a phased array, a curved array, a geometrically focused transducer, a plurality of single-element transducers having a common drive signal, and a convex transducer.

18. The system of claim 17 wherein the transducer further includes an acoustic lens.

19. The system of claim 16 wherein:

the transducer elements comprise a plurality of groups of elements;

the drive signals coupled to transducer elements within each group are substantially alike in phase shift; and

the drive signals substantially differ in phase shift between groups of elements.

20. The system of claim 19 wherein the second phase shift in the drive signals coupled to a first group of elements differs from the second phase shift in the drive signals coupled to a second group of elements by a phase factor of π

.

21. The system of claim 16 wherein the phase shift of the drive signal varies periodically.

22. The system of claim 21 wherein the phase shift of the drive signal varies between a plurality of predetermined states.

23. The system of claim 16 wherein the drive signals are adapted to electronically focus the array at a single location and produce a plurality of grating lobe foci at a predetermined group of locations.

24. The system of claim 23 wherein the drive signals are additionally adapted to produce a plurality of grating lobe foci at a second predetermined group of locations.

25. The system of claim 23 wherein the drive signals are additionally adapted to produce a plurality of grating lobe foci at varying predetermined groups of locations.

26. The system of claim 25 wherein the grating lobe foci are varied at least one of periodically and sequentially.

27. The system of claim 16 wherein the drive signals are adapted to electronically focus the array at variable locations and to produce a plurality of grating lobe foci at a predetermined group of locations.

28. The system of claim 27 wherein the drive signals are additionally adapted to produce a plurality of grating lobe foci at a second predetermined group of locations.

29. The system of claim 27 wherein the drive signals are additionally adapted to produce a plurality of grating lobe foci at varying predetermined groups of locations.

30. The system of claim 27 wherein the grating lobe foci are varied at least one of periodically and sequentially.

31. A method for medical treatment of tissue using ultrasound, comprising the steps of:

providing a probe having an array of transducer elements;

generating at least one electrical ultrasound signal;

generating from the at least one electrical ultrasound signal a plurality of phase-shifted drive signals; and

coupling each phase-shifted drive signal to an associated transducer element, effective to control grating lobe foci emitted by the array.

32. The method of claim 31, further comprising the step of electronically focusing the array.

33. The method of claim 31, further comprising the step of selecting a transducer that includes at least one of a substantially linear array, a phased array, a curved array, a geometrically focused transducer, a plurality of single-element transducers having a common drive signal, and a convex transducer.

34. The method of claim 33, further comprising the step of adding an acoustic lens to the transducer.

35. The method of claim 31, further comprising the steps of:

forming a plurality of groups of elements;

coupling drive signals that are substantially alike in phase shift to transducer elements within each group; and

substantially differing the phase shifts of drive signals between groups of elements.

36. The method of claim 31, further comprising the step of periodically varying the phase shifts of the drive signals.

37. The method of claim 36, further comprising the step of periodically varying the phase shifts of the drive signals between a plurality of predetermined states.

38. The method of claim 31, further comprising the step of electronically focusing the array at a single location to produce a plurality of grating lobe foci at a predetermined group of locations.

39. The method of claim 38, further comprising the step producing a plurality of grating lobe foci at a second predetermined group of locations.

40. The method of claim 38, further comprising the step of producing a plurality of grating lobe foci at varying predetermined groups of locations.

41. The method of claim 40, further comprising the step of varying the grating lobe foci at least one of periodically and sequentially.

42. The method of claim 31, further comprising the step of electronically focusing the array at variable locations to produce a plurality of grating lobe foci at a predetermined group of locations.

43. The method of claim 42, further comprising the step of producing a plurality of grating lobe foci at a second predetermined group of locations.

44. The method of claim 42, further comprising the step of producing a plurality of grating lobe foci at varying predetermined groups of locations.

45. The method of claim 42, further comprising the step of varying the grating lobe foci at least one of periodically and sequentially.