Multipolar electrosurgical device and method

Claims

What is claimed is:

1. An electrosurgical device for use in the treatment of tissue comprising:

a multipolar probe body sized to enable passage of the probe body through an endoscope channel, said probe body having a peripheral surface and a longitudinal axis extending from a proximal to a distal end of the probe body;

at least one electrically isolated conductor pair mounted on the probe body including means for connecting the conductor pair to a source of electrical energy, each conductor comprising at least two electrodes with each electrode of one conductor being separated from and being interposed with another electrode of the other conductor with a spacing therebetween, said different electrodes being further so distributed and respectively so sized in width and length so as to extend in spaced apart relationship over the distal end and over the peripheral surface side which is located radially from said longitudinal axis, the ratio of the width of electrodes to the spacing between the different electrodes being so selected as to enable effective bipolar treatment of tissue with effectively omni-directional probe body orientations relative to the tissue to be treated when the probe body is used.

2. The electrosurgical device as claimed in claim 1 wherein said ratio of the width of the electrodes to said spacing is selected to be at least greater than about one-third.

3. The electrosurgical device as claimed in claim 2 wherein said ratio lies in a range extending from about one half to about three.

4. The electrosurgical device as claimed in claim 1 wherein said ratio of the electrode width to said spacing is at least about unity.

5. The electrosurgical device as set forth in claim 1 wherein the conductors on the probe body are each branched into at least three electrodes extending over the distal end and side of the peripheral surface.

6. The electrosurgical device as claimed in claim 5 wherein each conductor is formed of at least three electrodes which are aligned parallel to the longitudinal axis along the peripheral side of the probe body.

7. The electrosurgical device as claimed in claim 6 wherein said probe body is smoothly curved at the distal end, said electrodes extending onto said distal end of the probe body to provide multiple bipolar contacts around the longitudinal axis of the probe body at said distal end.

8. The electrosurgical device as claimed in claim 1 wherein said probe body is formed of a rigid insulative material with a fluid channel extending through the rigid insulative material from a proximal to a distal end thereof, said fluid channel being sized to pass fluid to clear the tissue area to be treated.

9. The electrosurgical device as claimed in claim 6 wherein said fluid channel is provided with a conductive lining which is electrically connected to one of said electrically isolated conductors.

10. The electrosurgical device as claimed in claim 9 wherein said probe body has a generally blunt shaped distal end with a generally central opening therein corresponding to a distal end of said electrically conductive fluid channel, and wherein the conductor connected to the conductive lining includes a plurality of electrodes which extend over said shaped distal end of the probe body to connect to said conductive lining at the distal end, and wherein the other conductor includes a plurality of electrodes which extend over the distal end and terminate in spaced relationship from the electrodes connected to the conductive lining to form multipolar contact capability at the distal end of the probe body.

11. The electrosurgical device as claimed in claim 10 wherein electrodes are distributed at about equiangular spacing of the order of about 60.degree. about the longitudinal axis.

12. An electrosurgical device in accordance with claim 1, 2, 3, 4, 5, 8, 9, 10 or 11 wherein said conductors are thin metallized strips fused to the peripheral surface of the probe body to maintain a generally smooth external probe body surface.

13. The electrosurgical device as claimed in claim 10 wherein the probe body is further provided with a radially recessed annular shoulder at the proximal end and a ring electrode placed around the recessed shoulder and electrically connected to electrode of one of said conductors on the probe body.

14. The electrosurgical device as set forth in claim 13 wherein the recessed shoulder further is provided with a radially recessed notch sized to receive a wire connection.

15. The electrosurgical device as claimed in claim 1, 2, 3, 4, 5, 8, 9, 10 or 11 wherein said conductors are each formed of generally like sized and uniformly distributed fine strip electrodes fused to the outer peripheral surface of the probe body.

16. The electrosurgical device as claimed in claim 15 wherein said conductors each include at least three electrically connected longitudinal electrodes disposed generally parallel to the longitudinal axis on said peripheral surface of the probe body, with electrodes which are connected to different conductors being respectively successively circumferentially spaced from each other to provide said at least bipolar tissue contact capability around the periphery of the probe body.

17. The electrosurgical device as claimed in claim 1, 2, 3, 4, 8, 9, 10 or 11 wherein each conductor is formed with circular bands located on the peripheral surface and extending around the longitudinal axis.

18. An electrosurgical device for use in the treatment of tissue comprising:

an insulative probe body having a peripheral surface and a longitudinal axis extending from a proximal to a distal end of the probe body, said probe body being sized to pass through the channel of an endoscope;

electrically isolated conductors mounted on the probe body including means to connect the conductors to a source of electrical energy, said conductors being each formed with a plurality of fine strip shaped electrodes fused to the peripheral probe body surface, with electrodes of different conductors being respectively interposed with each other in fixed relationship on the peripheral surface of the probe body, said electrodes of different conductors being further respectively so sized and distributed so as to extend in spaced apart pairs over the distal end and over the radial side of said peripheral surface generally parallel with the longitudinal axis, with at least three of said electrode pairs being arranged on the probe body to enable at least bipolar treatment of tissue with effectively omnidirectional orientations of the probe body relative to the tissue to be treated when the probe body is used, the probe body being provided with a hollow conductive material located inside the probe body and extending from a proximal location of the probe body to its distal end, said conductive material being electrically connected at said distal end to the electrodes forming one of said conductors;

said hollow conductive material forming a fluid channel extending through the probe body from a proximal to a distal end thereof to pass fluid to clear tissue area to be treated, and wherein said electrodes forming the other of said conductors extend over the distal end of the probe body and terminiate in spaced relationship from the distal end of the conductive material to form a plurality of bipolar electrode pairs over the probe body distal end.

19. The electrosurgical device as claimed in claim 18 wherein said conductive material is in the form of a hollow conductive tube.

20. An electrosurgical device for use in the treatment of tissue comprising:

a multipolar probe body sized to enable passage of the probe body through an endoscope channel, said probe body having a peripheral surface and a longitudinal axis extending from a proximal to a distal end of the probe body;

electrically isolated conductor pairs mounted on the probe body including means for connecting the conductors to a source of electrical energy, with one conductor being interposed with another conductor with a spacing therebetween, said different conductors being further so distributed and respectively so sized in width and length so as to extend in spaced apart relationship over the distal end and over the peripheral surface side which is located radially from said longitudinal axis, the ratio of the width of conductors to the spacing between the different conductors being so selected as to enable effective bipolar treatment of tissue with effectively omnidirectional probe body orientations relative to the tissue to be treated when the probe body is used.

21. A method of bipolar electrosurgical coagulation of a bleeding tissue site with the use of high frequency electrical power comprising the step of:

applying from a distal end of a channel of an endoscope the electrical power to the bleeding site through at least a pair of spaced apart conductors having respective surface areas thereof in contact with the site to cause a coagulation of the bleeding tissue site, each conductor having at least two electrodes, the magnitude of said surface areas of the conductors and the spacing between the conductors being so selected as to obtain a generally uniform electrical heating of the bleeding site and a coagulation thereof without sticking of the conductors to the coagulated bleeding site, the ratio of the width of conductors to the spacing between the different conductors being so selected as to enable effective bipolar treatment of tissue with effectively omnidirectional orientations of the body upon which the conductors are on relative to the tissue to be treated.

22. The method as claimed in claim 21 wherein said electrical power applying step further includes the application of said electrical power to the bleeding site through spaced apart conductors which are so sized and located that the ratio of the width of the conductors to the spacing between them is sufficient to obtain said uniform heating and said coagulation without sticking.

23. The method as claimed in claim 22 wherein said electrical power applying step further includes the application of electrical power through conductors whose width and spacing is selected so that the ratio of said width to said spacing is greater than about one-third.

24. The method as claimed in claim 23 wherein the application of electrical power through conductors whose width and spacing is selected so that the rati