Electrode for electrosurgical coagulation of tissue

• US 6,168,593 B1
• Filed: 02/12/1998
• Issued: 01/02/2001
• Est. Priority Date: 02/12/1997
• Status: Expired due to Term

• Current Assignee: Oratec Interventions Incorporated
• Original Assignee: Oratec Interventions Incorporated
• Inventors: Sharkey, Hugh R., Fanton, Gary S., Reyes, Ramiro L.
• Primary Examiner(s): Lateef, Marvin M.
• Assistant Examiner(s): PATEL, MAULIN M
• Application Number:
  US09/022,688
• Time in Patent Office: 1,055 Days
• Field of Search: 607/115, 607/116, 600/374, 606/41-50
• US Class Current: 606/34
• CPC Class Codes: A61B 18/14 Probes or electrodes 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 18/1485 having a short rigid shaft for accessing the inner body through natural openings
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2018/00654 with individual control of each of a plurality of energy emitting elements
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00797 measured by multiple temperature sensors
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61N 1/06 for high-frequency therapy
• CPC Class Codes: A61N 1/403 for thermotherapy, e.g. hyperthermia

Abstract

An electrosurgical electrode, comprising a metal conductor having a first external surface area and having a convex body, a flat face on the body, and a connector for attaching the body to an electrosurgical probe handle, and an insulating layer covering the first external surface of the metal conductor except at a selected second area of one of the convex body and the flat face, the second area being positioned on the metal conductor so that a line from a geometric center of the second area and substantially perpendicular to the second area intersects at an angle an axis formed by a probe handle and the metal conductor upon attachment of a probe handle to the connector, wherein the second area does not intersect the axis along the probe handle. Also disclosed are methods of manufacture and similar off-axis electrodes useful in endoscopic electrosurgery.

Claims

1. An electrosurgical electrode, comprising:

a metal conductor having a first external surface area and having a convex body, a flat face on said body, and a connector for attaching said body to an electrosurgical probe handle, and

an insulating layer covering said first external surface of said metal conductor except at a selected second area of one of said convex body and said flat face, said second area being positioned on said metal conductor so that a line from a geometric center of said second area and substantially perpendicular to said second area intersects at an angle an axis formed by a probe handle and said metal conductor upon attachment of a probe handle to said connector.

2. The electrode of claim 1, wherein said metal conductor is biocompatible.

3. The electrode of claim 1, wherein said metal conductor is chosen from a group of metals consisting of:

stainless steel, gold, silver, and platinum.

4. The electrode of claim 1, wherein said convex body is substantially spherical except at said flat face and at said connector.

5. The electrode of claim 1, wherein said second area has an area of from 0.005 to 0.150 square inches.

6. The electrode of claim 1, wherein said second area has an area of from 0.010 to 0.080 square inches.

7. The electrode of claim 1, wherein said second area has an area of from 0.015 to 0.020 square inches.

8. The electrode of claim 1, wherein said second area is less than 30% of said first area.

9. The electrode of claim 1, wherein said angle is greater than 60°

.

10. The electrode of claim 1, wherein said angle is greater than 80°

.

11. The electrode of claim 4, wherein the spherical portion of said convex body has a radius of from 0.010 to 0.25 inch.

12. The electrode of claim 4, wherein the spherical portion of said convex body has a radius of from 0.040 to 0.060 inch.

13. The electrode of claim 1, wherein said body has a hollow interior.

14. The electrode of claim 1, wherein said first external surface area includes only surfaces of said convex body and said flat face.

15. An electrosurgical probe, comprising:

a handle,

an elongated probe neck connected to said handle and having a terminus distal to said handle, and

the electrode of claim 1 located at the terminus of said elongated probe neck.

16. An electrosurgical system, comprising:

an electrical power supply,

a first electrode adapted to contact and electrically ground a living body, said first electrode being electrically connected to said power supply, and

an electrosurgical probe, said probe comprising;

a handle,

an elongated probe neck connected to said handle and having a terminus at a distal end from said handle, and

a second electrode, said second electrode being the electrode of claim 1 and being located at the terminus of said elongated probe neck,

said probe being adapted to contact said body and complete an electrical circuit, said second electrode being electrically connected to said power supply.

17. The system of claim 16, wherein said power supply is a supply of radio frequency energy.

18. The system of claim 16, wherein said power supply is operably connected to a temperature-sensitive feedback monitor located in said probe.

19. A method for manufacturing an off-axis ablation device, comprising:

preparing a metal conductor having a first external surface area and having a first body shape and a connector for attaching said body to an electrosurgical probe handle,

applying an insulating layer to cover all of said first external surface of said metal conductor,

removing a portion of said insulating layer at a selected second area of body shape, said second area being positioned on said metal conductor so that a line from a geometric center of said second area and substantially perpendicular to said second area intersects an axis at an angle, said axis being formed by a probe handle and said metal conductor upon attachment of a probe handle to said connector.