ELECTROSURGICAL WAND AND RELATED METHOD AND SYSTEM

• US 20120095454A1
• Filed: 10/15/2010
• Published: 04/19/2012
• Est. Priority Date: 10/15/2010
• Status: Active Grant

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Cox, David A., Goode, Johnson E., Tetzlaff, Philip M., Woloszko, Jean
• Granted Patent: US 8,568,405 B2
• Time in Patent Office: Days
• US Class Current: 606/33
• CPC Class Codes: A61B 18/042 using additional gas becoming plasma
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00583 Coblation, i.e. ablation using a cold plasma
• CPC Class Codes: A61B 2018/00589 Coagulation
• CPC Class Codes: A61B 2018/1407 Loop
• CPC Class Codes: A61B 2018/144 Wire
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2218/002 Irrigation
• CPC Class Codes: A61B 2218/007 Aspiration

Abstract

Electrosurgical wand. At least some of the illustrative embodiment are electrosurgical wands including: an elongate housing that defines a handle end and a distal end; an aspiration aperture on the distal end of the elongate housing the aspiration aperture fluidly coupled to a first fluid conduit, the first fluid conduit within the elongate housing; a discharge aperture on the distal end of the elongate housing, the discharge aperture fluidly coupled to a second fluid conduit, and the second fluid conduit within the elongate housing; a first active electrode of conductive material on the distal end of the elongate housing, the first active electrode between the discharge aperture and the aspiration aperture; and a conductive plate that abuts the discharge aperture, at least a portion of the conductive plate disposed over the discharge aperture.

Claims

1. An electrosurgical wand comprising:

an elongate housing that defines a handle end and a distal end;

a connector comprising a first and second electrical pins;

an aspiration aperture on the distal end of the elongate housing, the aspiration aperture fluidly coupled to a first fluid conduit, the first fluid conduit within the elongate housing;

a discharge aperture on the distal end of the elongate housing, the discharge aperture fluidly coupled to a second fluid conduit, and the second fluid conduit within the elongate housing;

a first active electrode of conductive material on the distal end of the elongate housing, the first active electrode between the discharge aperture and the aspiration aperture, and the first active electrode electrically coupled to the first electrical pin; and

a conductive plate that abuts the discharge aperture, at least a portion of the conductive plate disposed over the discharge aperture, and the conductive plate electrically coupled to the second electrical pin.

2. The electrosurgical wand of claim 1 wherein the conductive plate defines a lip portion, and wherein at least a portion of the lip portion is disposed over the discharge aperture.

3. The electrosurgical wand of claim 2 wherein the lip portion is defined between a distal end of the conductive plate and a bend in the conductive plate.

4. The electrosurgical wand of claim 2 wherein the conductive plate has a curved portion and the lip portion is the distal end of the conductive plate.

5. The electrosurgical wand of claim 1 further comprising:

the first active electrode defines a first exposed surface area; and

the conductive plate defines a second exposed surface area greater than the first exposed surface area.

6. The electrosurgical wand of claim 1 wherein when viewed perpendicularly to a plane defined by the discharge aperture, the conductive plate occludes more than half an area defined by the discharge aperture.

7. The electrosurgical wand of claim 1 wherein first active electrode further comprises a loop of wire that defines a straight portion and two standoff portions.

8. The electrosurgical wand of claim 7 wherein the first active electrode has a standoff distance between and including 0.010 and 0.050 inches.

9. The electrosurgical wand of claim 7 wherein the first active electrode has a standoff distance of between and including 0.015 and 0.025 inches.

10. The electrosurgical wand of claim 7 wherein the loop of wire has a diameter of between and including 0.008 and 0.015 inches.

11. The electrosurgical wand of claim 7 wherein the loop of wire has a diameter of 0.010 inches.

12. The electrosurgical wand of claim 1 wherein at least a portion of the aspiration aperture is closer to the handle than the any portion of the discharge aperture.

13. The electrosurgical wand of claim 1 further comprising:

the distal end of the elongate housing defines a width and a thickness;

wherein first active electrode further comprises a loop of wire that defines a first straight portion;

a second active electrode that comprises a loop of wire that defines a second straight portion; and

the first and second straight portions are aligned along the width such that, when viewed along the thickness, the first and second straight portions overlap.

14. The electrosurgical wand of claim 13 wherein the first straight portion and the second straight portion are parallel.

15. The electrosurgical wand of claim 1 wherein the aspiration aperture defines an aperture width, and wherein the second fluid conduit transitions in width from the aperture width to an internal width over a length not less than two times the difference between the aperture width and the internal width.

16. A method comprising:

flowing a conductive fluid within a fluid conduit disposed within a electrosurgical wand, the conductive fluid is discharged through a discharge aperture in the direction of a return electrode, and the return electrode directs at least a portion of the conductive fluid toward an active electrode;

applying electrical energy between the active and return electrodes;

forming, responsive to the energy, a plasma proximate to the active electrode; and

treating a wound by placing the active electrode adjacent to the wound, and translating the active electrode along the wound.

17. The method of claim 16 wherein flowing further comprises flowing the conductive fluid past the return electrode in the form of a conductive plate with a distal bend.

18. The method of claim 16 wherein flowing further comprises flowing the conductive fluid past the return electrode in the form of a conductive plate with distal curvature.

19. The method of claim 16 wherein flowing further comprises flowing the conductive fluid such that the conductive fluid is directed toward the active electrode in the form of loop of wire.

20. The method of claim 16 further comprising aspirating through a fluid conduit in the electrosurgical wand, the aspirating proximate to the discharge aperture.

21. The method of claim 20 wherein treating the wound comprises detaching at least one wound tissue strip from the wound and aspirating the at least one strip away from the wound such that the at least one strip does not substantially contact an underlying remaining wound portion.

22. The method of claim 21 wherein detaching the at least one wound tissue strip comprises ablating at least a portion of the wound without completely molecularly dissociating the at least one strip.

23. The method of claim 20 wherein treating the wound comprises debriding at least a portion of the wound and aspirating a plurality of wound tissue strips away from the wound.

24. The method of claim 23 wherein the steps of debriding and aspirating further comprise removing a substantial concentration of bacteria from the wound.

25. The method of claim 16 further comprising engaging the wound with a bottom surface of the return electrode such that the bottom surface guides the wand during the translating step.

26. A system comprising:

an electrosurgical controller, the electrosurgical controller configured to produce radio frequency (RF) energy at an active terminal with respect to a return terminal;

an electrosurgical wand coupled to the electrosurgical controller, the electrosurgical wand comprising;

an elongate housing that defines a handle end and a distal end;

an aspiration aperture on the distal end of the elongate housing, the aspiration aperture fluidly coupled to a first fluid conduit, the first fluid conduit within the elongate housing;

a discharge aperture on the distal end of the elongate housing, the discharge aperture fluidly coupled to a second fluid conduit, and the second fluid conduit within the elongate housing;

a first active electrode of conductive material on the distal end of the elongate housing, the first active electrode between the discharge aperture and the aspiration aperture, and the first active electrode electrically coupled to active terminal of the electrosurgical controller; and

a conductive plate that abuts the discharge aperture, at least a portion of the conductive plate disposed over the discharge aperture, and the conductive plate electrically coupled to the return terminal of the electrosurgical controller.

27. The electrosurgical wand of claim 26 wherein the conductive plate defines a plane, and wherein an angle between the plane and the discharge aperture is an acute angle.

28. The electrosurgical wand of claim 26 wherein the conductive plate defines a straight portion and a lip portion, and wherein at least a portion of the lip portion is disposed over the discharge aperture.

29. The electrosurgical wand of claim 28 wherein the lip portion is defined between a distal end of the conductive plate and a bend in a medial portion of the conductive plate.

30. The electrosurgical wand of claim 28 wherein the conductive plate has a curved portion and the lip portion is the distal end of the conductive plate.

31. The electrosurgical wand of claim 26 further comprising:

the first active electrode defines a first exposed surface area; and

the conductive plate defines a second exposed surface area greater than the first exposed surface area.

32. The electrosurgical wand of claim 26 wherein when viewed perpendicularly to a plane defined by the discharge aperture, the return electrode occludes more than half an area defined by the discharge aperture.

33. The electrosurgical wand of claim 26 wherein first active electrode further comprises a loop of wire that defines a straight portion and two standoff portions.

34. The electrosurgical wand of claim 26 wherein at least a portion of the aspiration aperture is closer to the handle than the any portion of the discharge aperture.

35. The electrosurgical wand of claim 26 further comprising:

the distal end of the elongate housing defines a width and a thickness;

wherein first active electrode further comprises a loop of wire that defines a first straight portion;

a second active electrode that comprises a loop of wire that defines a second straight portion; and

the first and second straight portions are aligned along the width such that, when viewed along the thickness, the first and second straight portions overlap.

36. The electrosurgical wand of claim 35 wherein the first straight portion and the second straight portion are parallel.