Surgical system

• US 7,211,084 B2
• Filed: 08/25/2005
• Issued: 05/01/2007
• Est. Priority Date: 12/27/2001
• Status: Expired due to Term

• Current Assignee: Gyrus Medical Incorporated (Olympus Corporation)
• Original Assignee: Gyrus Group Limited (Olympus Corporation)
• Inventors: Marshall, Mark G., Goble, Colin Charles Owen, Batchelor, Kester J.
• Primary Examiner(s): Cohen; Lee S.
• Application Number:
  US11/210,671
• Publication Number:
  US 20060047280A1
• Time in Patent Office: 614 Days
• Field of Search: 606/45, 606 48- 50
• US Class Current: 606/48
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 2018/00005 Cooling or heating of the probe or tissue immediately surrounding the probe
• CPC Class Codes: A61B 2018/00023 closed, i.e. without wound contact by the fluid
• CPC Class Codes: A61B 2018/126 bipolar
• CPC Class Codes: A61B 2018/1412 Blade

Abstract

An electrosurgical cutting blade (1) comprises a first electrode (2), a second electrode (3), and an electrical insulator (4) separating the first and second electrodes. The first and second electrodes have dissimilar characteristics (cross-sectional area, thermal conductivity etc.) such that the first electrode (2) is encouraged to become an active electrode and the second electrode (3) is encouraged to become a return electrode. The spacing between the first and second electrodes (between 0.25 mm and 3.0 mm) and the peak voltage supplied to the electrodes (2 and 3) are both selected such that arcing does not occur directly between the electrodes, but between the first electrode and the tissue at the target site. The arrangement is such that, in use, a thermal differential of at least 50° C. is established between the first and second electrodes (2 and 3), such that the second electrode is maintained below a temperature of 70° C. This is achieved either by thermally insulating the second electrode from the first electrode, and/or by transferring heat away from the second electrode, e.g. by conduction, forced cooling, or by means of a heat pipe (27).

Claims

1. A bipolar blade comprising:

first and second electrodes, and

a first electrical insulator spacing apart the electrodes,

the first electrode having a cross-sectional area which is less than the cross-sectional area of the second electrode, such that the first electrode is encouraged to become an active electrode and the second electrode is encouraged to become a return electrode,

the spacing between the electrodes being between 0.25 mm and 1.0 mm, such that, when the electrodes are in contact with tissue and an electrosurgical cutting voltage is applied therebetween, arcing does not occur directly between the electrodes,

a third electrode adapted to coagulate tissue, the third electrode being separated from the second electrode by a second electrical insulator,

wherein the first, second and third electrodes are provided as layers in a sandwich structure with the first electrode being in the middle, there being layers of insulator between each of the electrodes, and

wherein the first electrode protrudes slightly beyond the periphery of the first and second insulators, around the circumference thereof, such that there is a surface discontinuity between each of the side surfaces of the first electrode and the corresponding side surfaces of the insulators spacing the first electrode apart from the second and third electrodes.

2. A bipolar blade according to claim 1, wherein the second and third electrodes are substantially semi-circular in cross-section.

3. A bipolar blade comprising:

a first electrode,

a second electrode,

a first electrical insulator spacing apart the first and second electrodes,

a third electrode, and

a second electrical insulator spacing apart the first and third electrodes,

the first, second and third electrodes and the first and second insulators forming layers in a sandwich structure with the first electrode being in the middle,

the first electrode having a cross-sectional area which is less than the cross-sectional area of the second and third electrodes, such that the first electrode is encouraged to become an active electrode and the second electrode and/or third electrode are/is encouraged to become a return electrode, when an electrosurgical cutting voltage is applied between the first electrode and the second electrode and/or third electrode,

the spacing between the first electrode and the second electrode and/or the third electrode being at least 0.25 mm to prevent arcing directly between the electrodes when the electrodes are in contact with tissue and the electrosurgical cutting voltage is applied between them, and

wherein the first electrode protrudes slightly beyond the periphery of the first and second insulators around the circumference thereof, such that there is a surface discontinuity between each of the side surfaces of the first electrode and the corresponding side surfaces of the insulators spacing the first electrode apart from the second and third electrodes.

4. The bipolar blade recited in claim 3, wherein the spacing between the first electrode and the second electrode and/or the third electrode is between 0.25 mm and 1.0 mm.

5. The bipolar blade recited in claim 3, wherein the first electrode protrudes slightly beyond the periphery of the second and third electrodes around the circumference thereof.

6. The bipolar blade recited in claim 3, wherein the second and third electrodes each have a relatively large surface for effective coagulation of tissue when an electrosurgical coagulation voltage is applied between them.

7. The bipolar blade recited in claim 3, wherein the second and third electrodes are each approximately semi-circular in cross section.

8. The bipolar blade recited in claim 7, wherein the second and third electrodes form a generally cylindrical structure with the first electrode protruding slightly from a central region thereof.

9. The bipolar blade recited in claim 3, wherein the first and second insulators each have a slanting beveled distal end, resulting in the second and third electrodes being set back axially from the first electrode in an axis of the blade.

10. The bipolar blade recited in claim 3, wherein the first electrode protrudes slightly beyond the ends of the second and third electrodes.

11. A bipolar blade comprising:

a first electrode,

a second electrode,

a first electrical insulator spacing apart the first and second electrodes,

a third electrode, and

a second electrical insulator spacing apart the first and third electrodes,

the first, second and third electrodes and the first and second insulators forming layers in a sandwich structure with the first electrode being in the middle,

the first electrode having a characteristic which is dissimilar from that of the second and third electrodes such that the first electrode is encouraged to become an active electrode and the second electrode and/or third electrode are/is encouraged to become a return electrode when an electrosurgical cutting voltage is applied between the first electrode and the second electrode and/or third electrode,

the spacing between the first electrode and the second electrode and/or the third electrode being at least 0.25 mm to prevent arcing directly between the electrodes when the electrodes are in contact with tissue and the electrosurgical cutting voltage is applied between them

wherein the first electrode is attached in a discontinuous manner with the first and second insulators to reduce the transfer of heat from the first electrode.

12. A bipolar blade comprising:

a first electrode,

a second electrode,

a first electrical insulator spacing apart the first and second electrodes,

a third electrode, and

a second electrical insulator spacing apart the first and third electrodes,

the first, second and third electrodes and the first and second insulators forming layers in a sandwich structure with the first electrode being in the middle,

the first electrode having a characteristic which is dissimilar from that of the second and third electrodes such that the first electrode is encouraged to become an active electrode and the second electrode and/or third electrode are/is encouraged to become a return electrode when an electrosurgical cutting voltage is applied between the first electrode and the second electrode and/or third electrode,

the spacing between the first electrode and the second electrode and/or the third electrode being at least 0.25 mm to prevent arcing directly between the electrodes when the electrodes are in contact with tissue and the electrosurgical cutting voltage is applied between them

wherein the first electrode is perforated with a plurality of holes to reduce the transfer of heat from the first electrode.

13. An electrosurgical system comprising:

a bipolar blade comprising;

a first electrode,

a second electrode,

a first electrical insulator spacing apart the first and second electrodes

a third electrode, and

a second electrical insulator spacing apart the first and third electrodes,

the first, second and third electrodes and the first and second insulators forming layers in a sandwich structure with the first electrode being in the middle,

an electrosurgical generator for applying a radio frequency voltage to the bipolar blade, the electrosurgical generator applying a radio frequency cutting voltage between the first electrode and the second electrode and/or the third electrode and a radio frequency coagulation voltage between the second and third electrodes,

the first electrode having a cross-sectional area which is less than the cross-sectional area of the second and third electrodes such that the first electrode is encouraged to become an active electrode and the second electrode and/or third electrode are/is encouraged to become a return electrode when the radio frequency cutting voltage is applied between the first electrode and the second electrode and/or third electrode,

the spacing between the first electrode and the second electrode and/or the third electrode being at least 0.25 mm to prevent arcing directly between the electrodes when the electrodes are in contact with tissue and the radio frequency cutting voltage is applied between them, and

wherein the first electrode protrudes slightly beyond the periphery of the first and second insulators around the circumference thereof, such that there is a surface discontinuity between each of the side surfaces of the first electrode and the corresponding side surfaces of the insulators spacing the first electrode apart from the second and third electrodes.