Fuse-electrode electrosurgical apparatus

• US 20070010808A1
• Filed: 07/06/2005
• Published: 01/11/2007
• Est. Priority Date: 07/06/2005
• Status: Active Grant

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Dahla, Robert
• Granted Patent: US 7,632,267 B2
• Time in Patent Office: Days
• US Class Current: 606/41
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 2018/00666 using a threshold value
• CPC Class Codes: A61B 2018/00761 Duration
• CPC Class Codes: A61B 2018/1495 Electrodes being detachable from a support structure

Abstract

An electrosurgical apparatus for performing a surgical procedure on a target site, comprising a shaft having a distal end portion, the distal end portion comprising an active electrode including a fuse leg, the fuse leg adapted to break and disable the instrument upon applying a voltage differential between the active electrode and a return electrode for a predetermined amount of time. In another embodiment, the present invention is a method of performing an electrosurgical procedure on a target tissue, comprising: placing an electrosurgical instrument in close proximity to the target tissue, the electrosurgical instrument comprising an active electrode having a pre-selected portion adapted to break and disable the instrument upon applying a voltage differential thereto for a working time; and applying the voltage differential.

Claims

1. An electrosurgical apparatus for performing a surgical procedure on a target site, comprising an active electrode assembly including a fuse leg adapted to break and disable said apparatus upon expiration of a predetermined amount of use of said apparatus.

2. The electrosurgical apparatus of claim 1, wherein said break is controlled by optimizing a parameter selected form the group consisting of a dimension of said fuse leg, a voltage applied to said fuse leg, a material comprising said fuse leg, and a conductive fluid in contact with said fuse leg.

3. The electrosurgical apparatus of claim 2, wherein said dimension of said fuse leg is preferably a width of about 0.008 inch to 0.015. inch, and more preferably a thickness of about 0.004 to about 0.007 inch.

4. The electrosurgical apparatus of claim 2, wherein said high frequency voltage preferably is about 50 volts to about 1000 volts, and more preferably about 200 volts to 350 volts.

5. The electrosurgical apparatus of claim 2, wherein said material is selected from the group consisting of platinum, tungsten, molybdenum, titanium and corrosion resistant stainless steel.

6. The electrosurgical apparatus of claim 1, wherein said predetermined use is about one hour, preferably about 2 minutes to about 30 minutes, and more preferably about 7 minutes to about 10 minutes.

7. The electrosurgical apparatus of claim 1, wherein said active electrode assembly comprises one or more anchor legs, and herein said anchor legs include said fuse leg.

8. The electrosurgical apparatus of claim 9, wherein said fuse leg is adapted to break before any of said anchor legs break and wherein said fuse leg is adapted for a higher current density compared the current density on said anchor legs.

9. The electrosurgical apparatus of claim 1, further comprising a high frequency voltage generator for supplying current to said electrode assembly.

10. The electrosurgical apparatus of claim 1, further comprising:

a shaft having a distal end wherein said electrode assembly is disposed on said distal end;

a return electrode disposed on said shaft proximally to said electrode assembly; and

an insulator positioned between said return electrode and said electrode assembly for electrically insulating said return electrode from said electrode assembly.

12. The electrosurgical apparatus of claim 12, wherein said fuse leg is partially embedded in said insulator.

11. The electrosurgical apparatus of claim 12, wherein said electrode assembly and said fuse leg comprise an active electrode.

13. The electrosurgical apparatus of claim 12, wherein said shaft defines an axial lumen opened at said distal end of said shaft.

14. The electrosurgical apparatus of claim 12, further comprising an aspiration tube disposed partly on said shaft for aspirating material away from said distal end.

15. The electrosurgical apparatus of claim 12, further including a fluid supply system disposed partly on said shaft for supplying conductive fluid to said distal end.

16. An electrosurgical instrument, comprising:

a shaft having a distal end portion, said distal end portion comprising an active electrode including a fuse leg, said fuse leg adapted to break and disable said instrument upon applying a voltage differential between said active electrode and a return electrode for a predetermined amount of time.

17. The electrical instrument of claim 16, further comprising one or more anchor legs for securing said active electrode assembly on said shaft.

18. The electrical instrument of claim 17, wherein said fuse leg is dimensioned to break before any of said anchor legs break.

19. The electrical instrument of claim 16, wherein a return electrode is positioned on said shaft proximally to said active electrode;

and

an insulator is interposed between said return electrode and active electrode on said shaft for electrically isolating said return electrode from said active electrode.

20. The electrosurgical apparatus of claim 16, further including a high frequency voltage supply electrically connected to said fuse leg.

21. A method of performing an electrosurgical procedure on a target tissue, comprising:

placing an electrosurgical instrument in close proximity to said target tissue, said electrosurgical instrument comprising a return electrode, and an active electrode having a pre-selected portion adapted to break and disable said instrument upon applying a voltage differential between said active and return electrodes for a working time; and

applying said voltage differential.

22. The method of claim 21, wherein said voltage differential is in a range of about 50 volts to about 1000 volts.

23. The method of claim 21, wherein said voltage differential is applied for about one hour, preferably about 2 minutes to about 30 minutes, and more preferably about 7 minutes to about 10 minutes.

24. The method of claim 21, wherein said pres-selected leg comprises a width of about 0.005 inch to about 0.125 inch.

25. The method of claim 21, wherein said electrosurgical procedure includes ablating said target tissue.