Method and apparatus for creating a bi-polar virtual electrode used for the ablation of tissue

• US 7,156,845 B2
• Filed: 09/16/2005
• Issued: 01/02/2007
• Est. Priority Date: 07/07/1998
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Hoey, Michael F., Mulier, Peter M. J.
• Primary Examiner(s): Cohen; Lee S.
• Application Number:
  US11/229,414
• Publication Number:
  US 20060009760A1
• Time in Patent Office: 473 Days
• Field of Search: 606/41, 606/48, 606/50, 604/114, 607/99, 607/105, 607/113
• US Class Current: 606/41
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1482 having a long rigid shaft for accessing the inner body transcutaneously in minimal invasive surgery, e.g. laparoscopy
• CPC Class Codes: A61B 2018/00005 Cooling or heating of the probe or tissue immediately surrounding the probe
• CPC Class Codes: A61B 2018/00053 Mechanical features of the instrument of device
• CPC Class Codes: A61B 2018/00291 using suction
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/126 bipolar
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2218/002 Irrigation
• CPC Class Codes: A61B 2218/007 Aspiration

Abstract

A method and apparatus for creating a virtual electrode to ablate bodily tissue. The apparatus includes an outer tube, a first electrode, an inner tube and a second electrode. The outer tube is fluidly connected to a source of conductive fluid and defines a proximal end and a distal end. The distal end includes an opening for delivering conductive fluid from the outer tube. The first electrode is disposed at the distal end of the outer tube for applying a current to conductive fluid delivered from the outer tube. The inner tube is coaxially received within the outer tube and is connected to a source of conductive fluid. The inner tube defines a proximal end and a distal end, with the distal end forming an opening for delivering conductive fluid from the inner tube. Finally, the second electrode is disposed at the distal end of the inner tube for applying a current to conductive fluid delivered from the inner tube. With this configuration, upon final assembly, the distal end of the outer tube is axially spaced from the distal end of the inner tube such that the first electrode is spaced from the second electrode. As a result, a bi-polar virtual electrode can be established.

Claims

1. A method for ablating tissue comprising:

providing a suction ablation device having a distal portion, the distal portion comprising;

a first electrode having a first lumen;

a second electrode spaced from the first electrode and having a second lumen; and

a suction member, wherein at least a portion of the suction member is positioned between the first and second electrodes;

positioning the first and second electrodes adjacent tissue;

providing suction to the suction member to draw tissue into contact with the suction ablation device;

flowing a fluid through the first and second lumens; and

providing an electric current to the first and second electrodes for ablating tissue.

2. The method of claim 1, wherein the fluid is provided from a fluid source.

3. The method of claim 1, wherein the fluid is an electrically conductive fluid.

4. The method of claim 3, wherein the electrically conductive fluid comprises saline.

5. The method of claim 1, wherein the electric current comprises radiofrequency alternating current provided from a radiofrequency generator.

6. The method of claim 1, wherein suction is provided from a vacuum source.

7. A method for ablating tissue comprising:

providing a suction ablation device having a distal portion, the distal portion comprising;

a first electrode;

a second electrode spaced from the first electrode; and

a suction member, wherein at least a portion of the suction member is positioned between the first and second electrodes;

positioning the first and second electrodes adjacent tissue;

providing suction to the suction member to draw tissue into contact with the suction ablation device;

providing a fluid to the first and second electrodes; and

providing an electric current to the first and second electrodes for ablating tissue.

8. The method of claim 7, wherein the fluid is provided from a fluid source.

9. The method of claim 7, wherein the fluid is an electrically conductive fluid.

10. The method of claim 9, wherein the electrically conductive fluid comprises saline.

11. The method of claim 7, wherein the electric current comprises radiofrequency alternating current provided from a radiofrequency generator.

12. The method of claim 7, wherein suction is provided from a vacuum source.

13. A method for ablating tissue comprising:

providing a suction ablation device having a distal portion, the distal portion comprising;

a first electrode;

a second electrode spaced from the first electrode;

a suction member, wherein at least a portion of the suction member is positioned between the first and second electrodes; and

a temperature sensor;

positioning the first and second electrodes adjacent tissue;

providing suction to the suction member to draw tissue into contact with the suction ablation device;

providing a fluid to the first and second electrodes;

providing an electric current to the first and second electrodes for ablating tissue; and

measuring a temperature.

14. The method of claim 13, wherein the fluid is provided from a fluid source.

15. The method of claim 13, wherein the fluid is an electrically conductive fluid.

16. The method of claim 15, wherein the electrically conductive fluid comprises saline.

17. The method of claim 13, wherein the electric current comprises radiofrequency alternating current provided from a radiofrequency generator.

18. The method of claim 13, wherein suction is provided from a vacuum source.

19. A method for ablating tissue comprising:

providing a suction ablation device having a distal portion, the distal portion comprising;

a first ablating member,

a second ablating member spaced from the first ablating member; and

a suction member, wherein at least a portion of the suction member is positioned between the first and second ablating members;

positioning at least a portion of the suction member between the first and second ablating members;

positioning the first and second ablating members adjacent tissue;

providing suction to the suction member to draw tissue into contact with the suction ablation device;

providing a fluid to the first and second ablating members; and

providing a radiofrequency energy to the first and second ablating members for ablating tissue.

20. The method of claim 19, wherein the radiofrequency energy is provided from a radiofrequency generator.

21. The method of claim 19, wherein suction is provided from a vacuum source.

22. The method of claim 19, wherein the fluid is provided from a fluid source.

23. The method of claim 22, wherein the fluid is an electrically conductive fluid.

24. The method of claim 23, wherein the electrically conductive fluid comprises saline.

25. The method of claim 19, wherein the first ablating member comprises an electrode.

26. The method of claim 19, wherein the second ablating member comprises an electrode.