Electrosurgical electrode having a non-conductive porous ceramic coating

• US 7,223,265 B2
• Filed: 02/16/2006
• Issued: 05/29/2007
• Est. Priority Date: 12/10/2002
• Status: Active Grant

• Current Assignee: Covidien AG (Medtronic Plc)
• Original Assignee: Sherwood Services AG
• Inventors: Keppel, David S.
• Primary Examiner(s): Cohen; Lee S.
• Application Number:
  US11/355,725
• Publication Number:
  US 20060161150A1
• Time in Patent Office: 467 Days
• Field of Search: 606/41, 606/45, 606 48- 52
• US Class Current: 606/41
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 2017/0088 ceramic
• CPC Class Codes: A61B 2018/00065 porous
• CPC Class Codes: A61B 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/00107 Coatings on the energy applicator
• CPC Class Codes: A61B 2018/1213 creating an arc

Abstract

An electrosurgical electrode assembly and method utilizing the same are disclosed capable of controlling or limiting the current per arc in real-time during an electrosurgical procedure. The conductive electrosurgical electrode is configured for being connected to an electrosurgical generator system and has a non-conductive, porous ceramic coating that “pinches” or splits the arc current generated by the electrosurgical generator system into the smaller diameter pores of the coating, effectively keeping the same current and voltage, but creating several smaller diameter arcs from one larger diameter arc. This has the effect of separating the arc current, effectively increasing the current frequency, resulting in a finer cut or other surgical effect. That is, the non-conductive, porous ceramic coating enables a low frequency current to achieve surgical results indicative of a high frequency current, while minimizing or preventing thermal damage to adjacent tissue.

Claims

1. An electrode assembly for controlling the electrosurgical arc current from an electrosurgical generator, the electrode assembly comprising:

an electrode having a conductive surface adapted to connect to a source of electrosurgical energy, said electrode including a width and a length;

a non-conductive, porous ceramic material substantially coating said conductive electrode, said non-conductive, porous ceramic material having a thickness and including a plurality of pores dispersed therein having a diameter and a depth, said non-conductive, porous ceramic material varying in thickness across at least one of the length and width of the electrode, wherein the diameter and the depth of said pores of said non-conductive, porous ceramic material vary across at least one of a length and a width of the electrode; and

wherein upon actuation of the electrosurgical generator, electrosurgical energy from the electrosurgical generator creates an initial arc current across the conductive surface of the electrode, the initial arc current having a diameter greater than the diameter of the pore such that the initial arc current is forced to split into a plurality of subsequent arc currents having a diameter smaller than the diameter of the initial arc current in order to conduct electrosurgical energy through the pores of the non-conductive, porous ceramic material.

2. An electrode assembly according to claim 1, wherein the number of pores per inch varies across at least one of a length and a width of the electrode.

3. An electrode assembly according to claim 1, wherein the diameter of said pores of said non-conductive, porous ceramic coating is within a range of about 10 to about 1000 micrometers.

4. An electrode assembly according to claim 1, wherein the depth of said pores of said non-conductive, porous ceramic coating is within a range of about 100 to about 500 micrometers.

5. An electrode assembly according to claim 1, wherein the non-conductive, porous ceramic material is dispersed on a pair of opposing jaw members of a forceps.

6. An electrode assembly according to claim 5, wherein the thickness of the non-conductive, ceramic material varies across a length of each of the opposing jaw members.

7. An electrode assembly according to claim 6, wherein the non-conductive, ceramic material on each of the jaw members includes a first thickness dispersed near a distal and a proximal end of each jaw member and a second thickness dispersed between the proximal and distal ends of each jaw member, said first thickness being dimensioned to effectively seal tissues disposed between the opposing jaw members upon electrosurgical activation and said second thickness being dimensioned to effectively cut tissue dispersed between the opposing jaw members upon electrosurgical activation.

8. An electrode assembly according to claim 1, wherein the electrode is at least one of a roller ball electrode and a blade electrode.

9. A method for controlling the amount of electrosurgical energy to tissue comprising the steps of:

providing an electrode having a conductive surface adapted to connect to a source of electrosurgical energy, said electrode including a width and a length;

coating said electrode with a non-conductive, porous ceramic material having a thickness and a plurality of pores dispersed therein each having a diameter and a depth, said non-conductive, porous ceramic material varying in thickness across at least one of the length and width of the electrode, wherein the diameter and the depth of said pores of said non-conductive, porous ceramic material vary across at least one of a length and a width of the electrode; and

activating the electrosurgical energy source to create an initial arc current across the conductive surface of the electrode, said initial arc having a diameter greater than the diameter of said pores such that the initial arc current is forced to split into a plurality of subsequent arc currents having a smaller diameter than the diameter of the initial arc current in order to conduct electrosurgical energy through the pores of the non-conductive, porous ceramic coating.

10. An electrode assembly according to claim 9, wherein the diameter of said pores of said non-conductive, porous ceramic coating is within a range of about 10 to about 1000 micrometers.

11. An electrode assembly according to claim 9, wherein the depth of said pores of said non-conductive, porous ceramic coating is within a range of about 100 to about 500 micrometers.

12. An electrode assembly for controlling the electrosurgical arc current from an electrosurgical generator, the electrode assembly comprising:

an electrode having a conductive surface adapted to connect to a source of electrosurgical energy, said electrode having a modified geometry adapted for controlling splitting of the electrosurgical arc;

a non-conductive, porous ceramic material substantially coating said conductive electrode, said non-conductive, porous ceramic material having a thickness and including a plurality of pores dispersed therein having a diameter and a depth wherein the diameter of said pores of said non-conductive, porous ceramic material varies across the modified geometry; and

wherein upon actuation of the electrosurgical generator, electrosurgical energy from the electrosurgical generator creates an initial arc current across the conductive surface of the electrode, the initial arc current having a diameter greater than the diameter of the pore such that the initial arc current is forced to split into a plurality of subsequent arc currents having a diameter smaller than the diameter of the initial arc current in order to conduct electrosurgical energy through the pores of the non-conductive, porous ceramic material.

13. An electrode assembly according to claim 12, wherein the number of pores per inch varies across at least one of a length and a width of the electrode.

14. An electrode assembly according to claim 12, wherein the diameter of said pores of said non-conductive, porous ceramic coating is within a range of about 10 to about 1000 micrometers.

15. An electrode assembly according to claim 12, wherein the depth of said pores of said non-conductive, porous ceramic coating is within a range of about 100 to about 500 micrometers.

16. An electrode assembly according to claim 12, wherein the non-conductive, porous ceramic material is dispersed on a pair of opposing jaw members of a forceps.

17. An electrode assembly according to claim 16, wherein the thickness of the non-conductive, ceramic material varies across the modified geometry of each of the opposing jaw members.

18. An electrode assembly according to claim 17, wherein the non-conductive, ceramic material on each of the jaw members includes a first thickness dispersed near a distal and a proximal end of each jaw member and a second thickness dispersed between the proximal and distal ends of each jaw member, said first thickness being dimensioned to effectively seal tissues disposed between the opposing jaw members upon electrosurgical activation and said second thickness being dimensioned to effectively cut tissue dispersed between the opposing jaw members upon electrosurgical activation.