ELECTROSURGICAL INSTRUMENT

• US 20070129728A1
• Filed: 02/12/2007
• Published: 06/07/2007
• Est. Priority Date: 10/22/2001
• Status: Active Grant

• Current Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Original Assignee: SurgRx, Inc. (Johnson & Johnson)
• Inventors: Truckai, Csaba, Shadduck, John, Strul, Bruno
• Granted Patent: US 7,381,209 B2
• Time in Patent Office: Days
• US Class Current: 606/51
• CPC Class Codes: A61B 18/1442 Probes having pivoting end effectors, e.g. forceps
• CPC Class Codes: A61B 18/1445 at the distal end of a shaft, e.g. forceps or scissors at the end of a rigid rod
• CPC Class Codes: A61B 2018/00077 high, i.e. electrically conducting
• CPC Class Codes: A61B 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/00125 with nanostructure
• CPC Class Codes: A61B 2018/00148 with metal
• CPC Class Codes: A61B 2018/0016 Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00404 Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/00601 Cutting
• CPC Class Codes: A61B 2018/0063 Sealing
• CPC Class Codes: A61B 2018/1412 Blade
• CPC Class Codes: A61B 2018/1455 having a moving blade for cutting tissue grasped by the jaws

Abstract

An embodiment of the invention includes an electrosurgical jaw structure that carries cooperating PTC bodies in both series and parallel circuit components for controlled RF energy application to engaged tissue to effectively weld tissue.

Claims

1. An electrosurgical instrument for applying energy to body structure, the instrument comprising first and second jaws carrying respective first and second energy-delivery elements coupled to an RF source by a first circuit component, the first energy-delivery element coupled to a resistive body in the first jaw, wherein the first energy-delivery element and the resistive body are coupled the RF source by a second circuit component.

2. An electrosurgical instrument as in claim 1, wherein the first circuit component comprises a series circuit when engaging body structure.

3. An electrosurgical instrument as in claim 1, wherein the second circuit component comprises a parallel circuit.

4. An electrosurgical instrument as in claim 1, wherein the second energy-delivery element is a PTC composition.

5. An electrosurgical instrument as in claim 4, wherein the resistive body is a PTC composition.

6. An electrosurgical instrument as in claim 5, wherein the second energy-delivery element PTC composition and the resistive body PTC composition define different temperature-impedance curves.

7. An electrosurgical instrument as in claim 6, wherein the second energy-delivery element PTC composition defines a substantially low impedance in a 40°

C. to 60°

C. range.

8. An electrosurgical instrument as in claim 6, wherein the second energy-delivery element PTC composition defines a substantially lower impedance in a 40°

C. to 60°

C. range than the resistive body PTC composition in a similar temperature range.

9. A method for welding tissue comprising:

providing an electrosurgical instrument having a tissue engaging surface, an electrode and a PTC body portion;

engaging a target tissue volume with the tissue engaging surface;

delivering RF energy to the target volume, wherein the PTC body portion modulates the delivery of energy responsive to a temperature of the PTC body portion; and

progressively creating a tissue weld in at least a portion of the target tissue volume.

10. The method of claim 9, further comprising:

producing a substantially uniformly fused tissue mass within the tissue volume.

11. The method of claim 9, further comprising:

contemporaneously welding and transecting the at least a portion of the target tissue volume.

12. The method of claim 9, further comprising:

utilizing the PTC body portion to modulate energy density at a pixilated level over at least a portion of the tissue engaging surface.

13. The method of claim 9, further comprising:

utilizing the PTC body portion to reduce tissue desiccation and charring in the at least a portion of the target tissue volume.

14. The method of claim 30, further comprising:

utilizing the PTC body portion to modulate a progression of ohmic heating.

15. A method for welding tissue comprising:

providing an electrosurgical instrument having a tissue engaging surface, an electrode and a PTC body portion;

engaging a target tissue volume with the tissue engaging surface;

delivering RF energy to the target volume;

modulating ohmic active heating of the engaged tissue volume on a microscale; and

welding at least a portion of the target tissue volume.

16. The method of claim 36, further comprising:

modulating ohmic active heating of the engaged tissue volume on a macroscale.