SYSTEM AND METHOD OF AN ELECTROSURGICAL CONTROLLER WITH OUTPUT RF ENERGY CONTROL

• US 20100228246A1
• Filed: 03/09/2009
• Published: 09/09/2010
• Est. Priority Date: 03/09/2009
• Status: Active Grant

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Marion, Duane W.
• Granted Patent: US 8,574,187 B2
• Time in Patent Office: Days
• US Class Current: 606/37
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/148 having a short, rigid shaft for accessing the inner body transcutaneously, e.g. for neurosurgery or arthroscopy
• CPC Class Codes: A61B 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 2018/00345 Vascular system
• CPC Class Codes: A61B 2018/00404 Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00619 Welding
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2218/002 Irrigation

Abstract

An electrosurgical controller with output RF energy control. At least some of the illustrative embodiments are electrosurgical controllers configured to change a first output voltage on the first active terminal relative to the first return terminal by selective control of a number of turns of the primary winding of a transformer used to create the output voltage.

Claims

1. An electrosurgical controller comprising:

a wand connector disposed on an outer surface of the electrosurgical controller, the wand connector configured to couple to a connector of an electrosurgical wand, and the wand connector comprising a plurality of electrical pins;

a voltage generator comprising;

a first active terminal coupled to a first electrical pin of the wand connector;

a first return terminal coupled to a second electrical pin of the wand connector; and

a transformer comprising a primary winding and a secondary winding, the secondary winding defines the first active and first return terminals;

the electrosurgical controller is configured to change a first output voltage on the first active terminal relative to the first return terminal by selective control of a number of turns of the primary winding used to create the output voltage.

2. The electrosurgical controller of claim 1 wherein the voltage generator further comprises:

an alternating current (AC) to direct current (DC) (AC-to-DC) conversion circuit configured to produce a DC output signal;

a center tap of the primary winding of the transformer, the center tap coupled to the DC output signal; and

a control circuit coupled to the primary winding, the control circuit configured to selectively control the number of turns of the primary winding used to create the first output voltage.

3. The electrosurgical controller of claim 2 wherein the voltage level of the DC output signal is fixed.

4. The electrosurgical controller of claim 2 wherein the AC-to-DC conversion circuit selectively changes a voltage level of DC output signal.

5. The electrosurgical controller of claim 2 wherein the voltage generator further comprises:

a first tap of the primary winding, the first tap defines a first number of turns relative to the center tap;

a second tap of the primary winding, the second tap defines a second number of turns relative to the center tap;

a third tap of the primary winding, the third tap defines a third number of turns relative to the center tap;

a fourth tap of the primary winding, the fourth tap defines a fourth number of turns relative to the center tap, the first and third taps define different number of turns than the second and fourth taps;

a first through fourth electrically controlled switches coupled one each to the first through fourth taps, respectively, each electrically controlled switch configured to selectively couple its respective tap to ground; and

the voltage generator configured to selectively control the number of turns of the primary winding used to create the first output voltage by selective activation of the electrically controlled switches.

6. The electrosurgical controller of claim 5 wherein each electrically controlled switch is a field effect transistor (FET).

7. The electrosurgical controller of claim 1 further comprising an interface device, the interface device configured to accept commands from a user of the electrosurgical controller, and the electrosurgical controller configured to change the first output voltage based on user interaction with the interface device.

8. The electrosurgical controller of claim 1 further comprising:

a second active terminal of the secondary winding, the second active terminal coupled a third electrical pin of the wand connector, the first active terminal relative to the first return terminal defines a first number of turns, the second active terminal relative to the first return terminal defines a second number of turns, and the first number of turns different than the second number of turns; and

the electrosurgical controller is configured to change a second output voltage on the second active terminal relative to the first return terminal by selective control of a number of turns of the primary winding utilized.

9. The electrosurgical controller of claim 8, wherein the first active terminal is electrically coupled to a first ablation electrode disposed at a distal end of the electrosurgical wand and the second active terminal is electrically coupled to a first coagulation electrode disposed at the distal end of the electrosurgical wand.

10. The electrosurgical controller of claim 8, wherein the first output voltage is sufficient to ablate tissue, and wherein the second output voltage is insufficient to ablate tissue and sufficient to coagulate blood at the tissue.

11. The electrosurgical controller of claim 1 further comprising:

a second active terminal of the secondary winding, the second active terminal coupled a third electrical pin of the wand connector; and

a second return terminal of the secondary winding, the second return terminal coupled to fourth electrical pin of the wand connector, the first active terminal relative to the first return terminal defines a first number of turns, the second active terminal relative to the second return terminal defines a second number of turns, and the first number of turns different than the second number of turns; and

the electrosurgical controller is configured to change a second output voltage on the second active terminal relative to the second return terminal by selective control of a number of turns of the primary winding utilized.

12. The electrosurgical controller of claim 11, wherein the first active terminal is electrically coupled to a first ablation electrode disposed at a distal end of the electrosurgical wand and the second active terminal is electrically coupled to a first coagulation electrode disposed at the distal end of the electrosurgical wand.

13. The electrosurgical controller of claim 11, wherein the first output voltage is sufficient to ablate tissue, and wherein the second output voltage is insufficient to ablate tissue and sufficient to coagulate blood at the tissue.

14. The electrosurgical controller of claim 1 further comprising:

the first active terminal relative to the first return terminal defines a first number of turns;

a second active terminal of the secondary winding, the second active terminal relative to the first return terminal defines a second number of turns;

a third active terminal of the secondary winding, the third active terminal relative to the first return terminal defines a third number of turns, the first number of turns different than both second and third number of turns, and the second number of turns different than the third number of turns;

a relay circuit coupled to the second and third active terminals, the relay circuit configured to selectively, and mutually exclusively, couple the second and third active leads to a third electrical pin of the wand connector.

15. The electrosurgical controller of claim 1 further comprising:

the first active terminal relative to the first return terminal defines a first number of turns;

a second return terminal of the secondary winding, the second return terminal coupled to a third electrical pin of the wand connector;

a second active terminal of the secondary winding, the second active terminal defines a second number of turns relative to the second return terminal;

a third active terminal of the secondary winding, the third active terminal defines a third number of turns relative to the second return terminal, the first number of turns different than both second and third number of turns, and the second number of turns different that the third number of turns; and

a relay circuit coupled to the second and third active terminals, the relay circuit configured to selectively, and mutually exclusively, couple the second and third active terminals to a fourth electrical pin of the wand connector.

16. A method comprising:

providing radio frequency (RF) energy at a first voltage to an electrosurgical wand; and

then

changing a number of utilized turns of a primary winding of a transformer through which the RF energy moves; and

thereby

providing RF energy at a second voltage, different than the first voltage, to the electrosurgical wand.

17. The method of claim 16 further comprising supplying, during both the providing of RF energy at the first and second voltage, a fixed direct current (DC) voltage to the primary winding of the transformer.

18. The method of claim 16 further comprising, contemporaneously with changing the number of utilized turns, changing a direct current (DC) voltage supplied to the primary winding.

19. The method of claim 16 wherein changing the number of utilized turns further comprises:

ceasing use of a first pair of electrically controlled switches coupled to the primary winding, each electrically controlled switch of the first pair coupled to a respective tap that each define a first number of turns of the primary winding relative to a center tap; and

using a second set of electrically controlled switches, each electrically controlled switch of the second pair coupled to respective taps that each define a second number of turns of the primary winding relative to the center tap, the first number of turns different than the second number of turns.

20. The method of claim 16 wherein the changing occurs within a half cycle of the RF energy.

21. The method of claim 16 wherein the first voltage is sufficient to ablate tissue, and wherein the second voltage is insufficient to ablate tissue and sufficient to coagulate blood at the tissue.

22. An electrosurgical controller comprising:

a wand connector disposed on an outer surface of the electrosurgical controller, the wand connector configured to couple to a connector of an electrosurgical wand, and the wand connector comprising a plurality of electrical pins;

a voltage generator comprising;

an alternating current (AC) to direct current (DC) (AC-to-DC) conversion circuit;

a primary winding of a transformer coupled to the AC-to-DC conversion circuit; and

a secondary winding of the transformer, the secondary winding defines a first active terminal coupled to a first electrical pin of the wand connector and a second active terminal coupled to a second electrical pin of the wand connector;

the electrosurgical controller is configured to simultaneously provide radio frequency (RF) energy having a first voltage to the first electrical pin and RF energy having a second voltage to the second electrical pin, wherein the first voltage is higher than the second voltage.

23. The electrosurgical controller of claim 22 wherein the secondary winding defines a first return terminal coupled to a third electrical pin of the wand connector, and wherein the first and second voltages are each relative to the first return electrode.

24. The electrosurgical controller of claim 22 wherein the secondary winding defines a first return electrode coupled to a third electrical pin of the wand connector, and the secondary winding defines a second return electrode coupled to a fourth electrical pin of the wand connector, and wherein the first voltage is relative to the first return electrode, and the second voltage is relative to the second return electrode.

25. The electrosurgical controller of claim 22 wherein the voltage generator further comprises a control circuit coupled to the primary winding, the control circuit configured to selectively control a number of turns of the primary winding used to create the first voltage and the second voltage.

26. The electrosurgical controller of claim 25 further comprising:

a center tap of the primary winding, the center tap coupled to the AC-to-DC conversion circuit;

a first tap of the primary winding, the first tap defines a first number of turns relative to the center tap, a second tap which defines a second number of turns relative to the center tap, a third tap which defines a third number of turns relative to the center tap, and a fourth tap which defines a fourth number of turns relative to the center tap, the first and third taps define different number of turns than the second and fourth taps;

a first through fourth electrically controlled switches coupled one each to the first through fourth taps, respectively, each electrically controlled switch configured to selective couple its respective tap to ground; and

a control circuit coupled to the electrically controlled switches, and the control circuit configured to control a turns ratio of the transformer number of turns of the primary winding used to create first and second voltages by selective control of the electrically controlled switches.

27. The electrosurgical controller of claim 22 further comprising:

a first active lead of the secondary winding coupled to the first active terminal;

a second active lead of the secondary winding;

a third active lead of the secondary winding; and

a relay circuit coupled between the second and third active leads and the second active terminal, the relay circuit configured to selectively, and mutually exclusively, couple the second and third active leads to the second active terminal.

28. The electrosurgical controller of claim 27 further comprising at least one selected from the group consisting of:

a first return terminal of the secondary winding coupled to an electrical pin of the wand connector, and wherein voltages on the first active terminal and second active terminal are with respect to the first return terminal; and

a first and second return terminal of the secondary winding each coupled to a respective electrical pin of the wand connector, and wherein the first voltage is with respect to the first return terminal and the second voltage is with respect to the second return terminal.

29. The electrosurgical controller of claim 22, wherein the first active terminal is electrically coupled to a first ablation electrode disposed at a distal end of the electrosurgical wand and the second active terminal is electrically coupled to a first coagulation electrode disposed at the distal end of the electrosurgical wand.

30. The electrosurgical controller of claim 22, wherein the first output voltage is sufficient to ablate tissue, and wherein the second output voltage is insufficient to ablate tissue and sufficient to coagulate blood at the tissue.

31. An electrosurgical controller comprising:

a wand connector disposed on an outer surface of the electrosurgical controller, the wand connector configured to couple to a connector of an electrosurgical wand, and the wand connector comprising a plurality of electrical pins;

a voltage generator comprising;

a transformer comprising a primary winding and a secondary winding;

a first active terminal of the secondary winding, the first active terminal coupled to a first electrical pin of the wand connector;

a first return terminal of the secondary winding, the first return terminal coupled to a second electrical pin of the wand connector;

a second active terminal of the secondary winding;

a third active terminal of the secondary winding;

a relay circuit coupled to the second and third active terminals, the relay circuit configured to selectively, and mutually exclusively, couple the second and third active terminals a third electrical pin of the wand connector;

the electrosurgical controller is configured to simultaneously provide radio frequency (RF) energy having a first voltage to the first electrical pin and RF energy having a second voltage to the second electrical pin, wherein the first voltage is higher than the second voltage.

32. The electrosurgical controller of claim 31 wherein the first voltage and the second voltage is relative to the first return terminal.

33. The electrosurgical controller of claim 31 further comprising:

a second return terminal of the secondary winding, the second return terminal coupled to a fourth electrical pin of the wand connector; and

wherein the first voltage is relative to the first return terminal, and the second voltage is relative to the second return terminal.

34. The electrosurgical controller of claim 31 further comprising:

the first active terminal relative to the first return terminal defines a first number of turns

the second active terminal relative to the first return terminal defines a second number of turns; and

the third active terminal relative to the first return terminal defines a third number of turns;

wherein the first number of turns different than both second and third number of turns, and the second number of turns different than the third number of turns.

35. The electrosurgical controller of claim 31, wherein the first active terminal is electrically coupled to a first ablation electrode disposed at a distal end of the electrosurgical wand and the second and third active terminals are respectively electrically coupled to a first and second coagulation electrode disposed at the distal end of the electrosurgical wand.

36. The electrosurgical controller of claim 31, wherein the first output voltage is sufficient to ablate tissue, and wherein the second output voltage is insufficient to ablate tissue and sufficient to coagulate blood at the tissue.

37. A method comprising:

providing a first radio frequency (RF) energy at a first voltage to a first electrode of an electrosurgical wand; and

simultaneously providing a second radio frequency (RF) energy at a second voltage through a first winding of a secondary winding of a transformer to a second electrode of an electrosurgical wand, and the first voltage different than the second voltage; and

then

ceasing providing the second RF energy; and

providing a third RF energy at a third voltage to the second electrode by way of a second winding of the secondary winding of a transformer, the second voltage different than the third voltage, and the third RF energy provided simultaneously with the first RF energy.

38. The method of claim 37 further comprising, prior to ceasing and providing the third RF energy, changing both the first and second voltage.

39. The method of claim 37 wherein changing further comprises changing a number of utilized turns of a primary winding of the transformer.

40. The method of claim 37 wherein ceasing and providing the third RF energy further comprises changing the conductive state of a set of electrically controlled switches coupled between the first and second windings of the secondary winding and the second electrode of the electrosurgical wand.

41. The method of claim 37 wherein the first voltage is sufficient to ablate tissue, and wherein each of the second and third voltage is insufficient to ablate tissue and sufficient to coagulate blood at the tissue.