Method of Operating an Ultrasound Handpiece

• US 20080281253A1
• Filed: 05/10/2007
• Published: 11/13/2008
• Est. Priority Date: 05/10/2007
• Status: Active Grant

• Current Assignee: Alcon Incorporated
• Original Assignee: Novartis Ag
• Inventors: Injev, Valentine P., Cionni, Robert J.
• Granted Patent: US 8,303,530 B2
• Time in Patent Office: Days
• US Class Current: 604/22
• CPC Class Codes: A61B 2017/320098 with transverse or torsional motion
• CPC Class Codes: A61F 9/00745 using mechanical vibrations, e.g. ultrasonic
• CPC Class Codes: A61M 2205/3344 Measuring or controlling pressure at the body treatment site
• CPC Class Codes: B06B 1/0261 taken from a transducer or electrode connected to the driving transducer
• CPC Class Codes: B06B 3/00 Methods or apparatus specially adapted for transmitting mechanical vibrations of infrasonic, sonic, or ultrasonic frequency

Abstract

A method employing a handpiece having at least one set of piezoelectric elements polarized to produce longitudinal motion when excited at the relevant resonant frequency. The piezoelectric crystals are connected to an ultrasonic horn to which a cutting tip is attached. The horn and/or the cutting tip contains a plurality of diagonal slits or grooves. The slits or grooves produce optimized torsional movement in the cutting tip when the piezoelectric crystals are excited at a second resonant frequency. When in torsional mode, material may clog the cutting tip. The present method includes the step of providing a pulse of longitudinal movement of the tip when clogging is detected.

Claims

1. A method of operating an ultrasonic handpiece, comprising:

a) providing an ultrasound handpiece having a handpiece shell, a plurality of piezoelectric elements connected to an ultrasound horn, the piezoelectric elements and the horn held within the shell, and an aspiration line;

b) subjecting the piezoelectric elements to a drive signal having a first frequency, the first frequency producing torsional movement in the horn;

c) sensing a vacuum in the aspiration line; and

d) subjecting the piezoelectric elements to a drive signal having a second frequency when the sensed vacuum in the aspiration line exceeds a predetermined threshold, the second frequency producing longitudinal movement in the horn.

2. The method of claim 1 wherein the drive signal having the first frequency and the drive signal having the second frequency do not overlap.

3. The method of claim 1 wherein the drive signal having the first frequency and the drive signal having the second frequency overlap.

4. The method of claim 1 wherein the drive signal having the first frequency is applied continuously and the drive signal having the second frequency is pulsed in response to the sensed vacuum in the aspiration line.

5. The method of claim 4 wherein the drive signal having the first frequency or the drive signal having the second frequency have a variable pulse duration and/or timing.

6. A method of operating an ultrasonic handpiece, comprising:

a) providing an ultrasound handpiece having a handpiece shell, a plurality of piezoelectric elements connected to an ultrasound horn, the piezoelectric elements and the horn held within the shell, and an aspiration line;

b) subjecting the piezoelectric elements to a primary drive signal;

c) sensing a vacuum in the aspiration line; and

d) subjecting the piezoelectric elements to a secondary drive signal when the sensed vacuum in the aspiration line exceeds a predetermined threshold.

7. The method of claim 6 wherein the primary drive signal and the secondary do not overlap.

8. The method of claim 6 wherein the primary drive signal the secondary drive signal overlap.

9. The method of claim 6 wherein the primary drive signal is applied continuously and the secondary drive signal is pulsed in response to the sensed vacuum in the aspiration line.

10. The method of claim 6 wherein the primary drive signal has a variable pulse duration and/or timing.

11. The method of claim 6 wherein the primary drive signal or the secondary drive signal have a variable pulse duration and/or timing.

12. A method of operating an ultrasonic handpiece, comprising:

a) providing an ultrasound handpiece having a handpiece shell, a plurality of piezoelectric elements connected to an ultrasound horn, the piezoelectric elements and the horn held within the shell;

b) subjecting the piezoelectric elements to a primary drive signal; and

c) subjecting the piezoelectric elements to a secondary drive signal when the primary drive signal reaches a pre-selected power level.

13. The method of claim 12 wherein the primary drive signal and the secondary drive signal do not overlap.

14. The method of claim 12 wherein the primary drive signal and the secondary drive signal overlap.

15. The method of claim 12 wherein the primary drive signal is applied continuously and the secondary drive signal is pulsed.

16. The method of claim 12 wherein the primary drive signal or the secondary drive signal have a variable pulse duration and/or timing.

17. The method of claim 12 wherein the secondary drive signal has a variable power level.

18. A method of operating an ultrasonic handpiece, comprising:

a) providing an ultrasound handpiece having a handpiece shell, a plurality of piezoelectric elements connected to an ultrasound horn, the piezoelectric elements and the horn held within the shell;

b) subjecting the piezoelectric elements to a variable primary drive signal; and

c) subjecting the piezoelectric elements to a variable secondary drive signal when the primary drive signal reaches a pre-selected power level.

19. The method of claim 18 wherein the primary drive signal and the secondary drive signal do not overlap.

20. The method of claim 18 wherein the primary drive signal and the secondary drive signal overlap.

21. The method of claim 18 wherein the primary drive signal is applied continuously and the secondary drive signal is pulsed.

22. The method of claim 18 wherein the primary drive signal or the secondary drive signal have a variable pulse timing.

23. The method of claim 18 wherein the secondary drive signal has a variable power level.