Cool RF Electrode

• US 20140081260A1
• Filed: 06/06/2011
• Published: 03/20/2014
• Est. Priority Date: 06/06/2011
• Status: Active Grant

• Current Assignee: Cosman Instruments, LLC
• Original Assignee: Eric R. Cosman Jr, Eric R. Cosman Sr
• Inventors: Cosman, Eric R. Jr., Cosman, Eric R. Sr.
• Granted Patent: US 10,588,687 B2
• Time in Patent Office: Days
• US Class Current: 606/41
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1477 Needle-like probes
• 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 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 2018/00011 with fluids
• CPC Class Codes: A61B 2018/00023 closed, i.e. without wound contact by the fluid
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/1425 Needle
• CPC Class Codes: A61B 2090/3925 ultrasonic
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image

Abstract

A system and method for applying energy, particularly radiofrequency (RF) electrical energy, to a living body can be used in tissue ablation.

Claims

1. An electrode system for adapted for introduction into bodily tissue comprising:

A cannula having a cannula distal end and a cannula proximal end, the cannula having a cannula hub at the cannula proximal end, said cannula having a cannula shaft having a lumen there-through, and the cannula shaft having a cannula insulated portion of its external surface that is insulated;

A stylet having a stylet shaft with a stylet distal end and a stylet proximal end, the stylet having a stylet hub at the stylet proximal end, the stylet being adapted to be inserted into said cannula lumen, so that said stylet hub can engage with said cannula hub, and said cannula and said stylet being adapted so that when said the stylet is inserted into said cannula, the combination of said cannula and said stylet is tissue piercing and said combination is adapted to be inserted into bodily tissue;

An electrode having an electrode shaft with an electrode distal end and an electrode proximal end, the electrode having an electrode hub at the electrode proximal end, said electrode having an electrode shaft that is adapted to be inserted into said cannula lumen, said electrode hub can engage with said cannula hub, said electrode shaft having at least in part an electrode uninsulated portion on its surface, so that when said electrode shaft is inserted into said cannula so that the electrode hub engages with the cannula hub, the combination of said cannula shaft and said electrode shaft has a combined exposed tip that comprises the uninsulated external surface said combination of shafts, and at least a part of the electrode uninsulated portion is within said a lumen of said cannula, and when said electrode shaft is inserted into said cannula so that said electrode hub engages with said cannula hub, said electrode distal end is in substantially the same position relative to said cannula distal end as is said stylet distal end is relative to said cannula distal end when said stylet is inserted into said cannula so that'"'"'s said stylet hub engages with said cannula hub;

and said electrode being adapted for connection to a high-frequency generator so that output signal from the high-frequency generator is connected to said electrode uninsulated portion, and said electrode and said cannula are adapted so that when said electrode is inserted into said cannula so that said electrode hub engages with said cannula hub, then when said electrode is connected to said output signal of said high-frequency generator, said output signal is connected to said combined exposed tip;

said electrode has an internal fluid channel, a fluid input port and a fluid output port, the input and output ports being adapted to be connected to a source of coolant fluid so that the coolant fluid can flow into the input port, through the internal fluid channel, and out of the output port, whereby said combined exposed tip is cooled by said coolant fluid when said electrode is inserted into said cannula so that said electrode hub engages said cannula hub.

2. The system of claim 1, wherein said cannula shaft comprises a metal tube, and said electrode uninsulated portion lies within the metal tube and is in electrical contact with said metal tube when said electrode hub and said cannula hub are engaged.

3. The system of claim 1, wherein the length of said stylet shaft and said electrode shaft are substantially equal.

4. The system of claim 1, wherein said stylet shaft is a rigid tissue piercing shaft.

5. The system of claim 1, wherein said electrode shaft has a non-tissue piercing tip at said electrode distal end.

6. The system of claim 1, wherein said electrode shaft has a tissue piercing tip at said electrode distal end.

7. The system of claim 1, and further including a conductive wire adapted to connect said high-frequency electrode to the output signal of a high-frequency generator,

8. The system of claim 1, wherein said stylet comprises a needle with an open needle lumen there-through and an obturating stylet that is adapted to be inserted into the needle lumen.

9. The system of claim 1, wherein the hub of said electrode is 10 mm or less in width.

10. The system of claim 1, wherein substantially all of the outer structural element of said electrode shaft comprises a rigid metal tube.

11. The system of claim 1, wherein said cannula, and/or stylet, and/or electrode comprises x-ray visible markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an x-ray, fluoroscopy, CT, or other radiographic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the structures in the patient'"'"'s body.

12. The system of claim 1, wherein said cannula, and/or stylet, and/or electrode comprises ecogenic markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an ultrasonic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the structures in the patient'"'"'s body.

13. The electrode system of claim 1 wherein,

Said cannula shaft is substantially insulated over its external surface;

Said stylet has a sharpened tissue piercing point on the stylet distal end, the stylet being adapted be inserted into said cannula lumen so that said stylet hub engages with said cannula hub, then the stylet distal end will extend beyond said cannula distal end by a known length, and said cannula and said stylet being adapted so that when said stylet is inserted into said cannula, said stylet and said cannula can be inserted together into bodily tissue,

Said electrode being adapted so that when said electrode is inserted into said cannula lumen and said electrode hub engages with said cannula hub, the electrode distal end extends beyond said cannula distal end by the same length as said known length, and the portion of the electrode shaft that extends beyond the cannula distal end is uninsulated.

14. The system of claim 13, wherein said stylet comprises a needle and a needle'"'"'s stylet which have a sharpened tissue piercing point.

15. The system of claim 13, wherein said known length is greater than 6 mm.

16. The system of claim 13, wherein said known length is about 10 mm.

17. The system of claim 13, wherein said known length is about 20 mm.

18. The system of claim 13, wherein said known length is about 30 mm.

19. The system of claim 13, wherein said known length is about 40 mm.

20. The system of claim 13, wherein said known length is about 25 mm.

21. The system of claim 13, wherein said known length is about 50 mm.

22. The system of claim 13, wherein said known length is about 60 mm

23. The system of claim 13, wherein said known length is greater than 60 mm

24. The system of claim 13, wherein the structural element of said electrode shaft'"'"'s outer wall is metal.

25. The system of claim 13, that comprises at least two cannulas, each of the cannulas having pre-determined length of said cannula shafts, and the predetermined lengths of the cannula shafts are different from each other, each of said cannulas having a cannula distal end and a cannula proximal end, and having a cannula hub at the cannula proximal end, and each of said cannulas having a cannula shaft having a lumen there-through, and each of said cannula shafts are substantially insulated;

Whereby, when either said tissue piercing needle or said electrode is inserted into each of said at least two cannulas so that either said needle hub or said electrode hub engages with the hub of said each of said cannulas, the length of extension that either said needle distal end or said electrode distal end extends beyond said each of said cannulas are equal, and the length of extension for each of said cannulas is predetermined and different from each other.

26. The system of claim 25, wherein said length of extension is a known length for each of said cannulas.

27. The electrode system of claim 1 wherein,

Said cannula shaft has said cannula insulated portion and a cannula uninsulated portion, the cannula uninsulated portion comprises an uninsulated surface of said cannula shaft at the cannula distal end of known cannula tip length,

And wherein said cannula uninsulated portion is substantially all of said combined exposed tip,

And wherein said electrode has an internal fluid channel, a fluid input port and a fluid output port, the input and output ports being adapted be connected a source of coolant fluid so that the coolant fluid can flow into the input port, through the internal fluid channel, and out of the output port so that said electrode distal end is cooled by said coolant fluid, and said electrode and said cannula are adapted so that said electrode distal end cools said cannula uninsulated portion when said electrode is inserted into said cannula so that said electrode hub engages said cannula hub.

28. The system of claim 27, wherein said combination of said stylet and said cannula has a combined distal tip having a sharpened tissue piercing point.

29. The system of claim 27, wherein said known cannula tip length is about 10 mm.

30. The system of claim 27, wherein said known cannula tip length is about 20 mm.

31. The system of claim 27, wherein said known cannula tip length is about 30 mm.

32. The system of claim 27, wherein said known cannula tip length is about 40 mm.

33. The system of claim 27, wherein said known cannula tip length is about 25 mm.

34. The system of claim 27, wherein said known cannula tip length is about 50 mm.

35. The system of claim 27, wherein said known cannula tip length is about 60 mm

36. The system of claim 27, wherein said known cannula tip length is greater than 60 mm

37. The system of claim 27, that comprises at least two cannulas, each of the cannulas having pre-determined length of said cannula uninsulated portion, and the predetermined lengths of the cannula uninsulated portions are different from each other, each of said cannulas having a cannula distal end and a cannula proximal end, and having a cannula hub at the cannula proximal end, and each of said cannulas having a cannula shaft having a lumen there-through;

Whereby, when either said tissue piercing needle or said electrode is inserted into each of said At least two cannulas so that either said needle hub or said electrode hub engages with the hub of said each of said cannulas, the length of extension that either said needle distal end or said electrode distal end extends beyond said each of said cannulas are equal.

38. The system of claim 37, wherein said predetermined lengths of extension are a known length for each of said cannulas.

39. An electrode system adapted introduction into bodily tissue comprising:

A cannula having a cannula distal end and a cannula proximal end, the cannula having a cannula hub at the cannula proximal end, said cannula having a cannula shaft having a lumen there-through, and the cannula shaft is substantially insulated;

A tissue piercing needle having a needle shaft with a needle distal end and a needle proximal end, the needle having a needle hub at the needle proximal end and having a sharpened tissue piercing point on the needle distal end, the needle being adapted be inserted into said cannula lumen, so that when said needle hub engages with said cannula hub, then the needle distal end will extend beyond said cannula distal end by a known length, and said cannula and said needle being adapted so that when said needle is inserted into said cannula, said needle and said cannula can be inserted together into bodily tissue,

An electrode having an electrode shaft with an electrode distal end and an electrode proximal end, the electrode having an electrode hub at the electrode proximal end, and said electrode having a shaft portion that is adapted to be inserted into said cannula lumen, so that when said electrode hub engages with said cannula hub, then the portion of the electrode shaft that extends beyond the cannula distal end is uninsulated, and the electrode distal end extends beyond said cannula distal end by the same length as said known length,

And said electrode being adapted to be connected to a high-frequency generator so that output signal from the high-frequency generator is connected to said uninsulated portion of the electrode shaft that extends beyond said cannula distal end.

whereby, said cannula with said needle inserted within said cannula can be inserted into bodily tissue so that said needle distal end is located at a target position within said bodily tissue, said needle can be removed from said cannula and said electrode can be inserted into said cannula so that said distal end of said electrode can be directed along the same tract as said needle within said cannula so that said electrode distal end is located at the same target position,

and whereby said uninsulated portion of said electrode that extends beyond said needle distal end can be energized by said output signal of said high-frequency generator to heat the bodily tissue near said uninsulated portion of said electrode that extends beyond said cannula distal end.

40. The system of claim 39, wherein the length of said needle shaft and said electrode shaft are substantially equal.

41. The system of claim 39, wherein said needle shaft is a rigid tissue piercing shaft.

42. The system of claim 39, wherein said electrode shaft has a non-tissue piercing tip at said electrode distal end.

43. The system of claim 39, wherein said electrode shaft has a tissue piercing tip at said electrode distal end.

44. The system of claim 39, and further including a conductive wire adapted to connect said high-frequency electrode to the output signal of a high-frequency generator,

45. The system of claim 39 wherein said known length is greater than 6 mm.

46. The system of claim 39, wherein said known length is about 10 mm.

47. The system of claim 39, wherein said known length is about 20 mm.

48. The system of claim 39, wherein said known length is about 30 mm.

49. The system of claim 39, wherein said known length is about 40 mm.

50. The system of claim 39, wherein said known length is about 50 mm.

51. The system of claim 39, wherein said known length is about 60 mm.

52. The system of claim 39, wherein said known length is greater than 60 mm.

53. The system of claim 39, wherein said cannula, and/or stylet, and/or electrode comprises ecogenic markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an ultrasonic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the structures in the patient'"'"'s body.

54. The system of claim 39, wherein said cannula, and/or stylet, and/or electrode comprises x-ray visible markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an x-ray, fluoroscopy, CT, or other radiographic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the structures in the patient'"'"'s body.

55. The system of claim 39, wherein said electrode has an internal fluid channel, a fluid input port and a fluid output port, the input and output ports being adapted be connected a source of coolant fluid so that the coolant fluid can flow into the input port, through the internal fluid channel, and out of the output port, whereby said uninsulated portion of said electrode that extends beyond said cannula distal end is cooled by said coolant fluid.

56. The system of claim 55, wherein the diameter of said electrode hub is less than 10 mm.

57. The system of claim 39, that comprises at least two cannulas, each of the cannulas having pre-determined length of said cannula shafts, and the predetermined lengths of the cannula shafts are different from each other, each of said cannulas having a cannula distal end and a cannula proximal end, and having a cannula hub at the cannula proximal end, and each of said cannulas having a cannula shaft having a lumen there-through, and each of said cannula shafts are substantially insulated;

Whereby, when either said tissue piercing needle or said electrode is inserted into each of said at least two cannulas so that either said needle hub or said electrode hub engages with the hub of said each of said cannulas, the length of extension that either said needle distal end and/or said electrode distal end extends beyond said each of said cannulas are equal, and the length of extension for each of said cannulas is predetermined and different from each other.

58. The system of claim 57, wherein said length of extension is a known length for each of said cannulas.

59. The system of claim 39, wherein substantially all of the outer portion of said electrode shaft comprises a rigid metal tubing.

60. The system of claim 39, wherein substantially all of said electrode shaft has an uninsulated conductive surface.

61. A system for heating of bodily tissue comprising:

A cannula having a cannula distal end and a cannula proximal end, the cannula having a cannula hub at the cannula proximal end, said cannula having a cannula shaft having a lumen there-through, and the cannula shaft is substantially insulated,

A tissue piercing needle having a needle shaft with a needle distal end and a needle proximal and, the needle having a needle hub at the needle proximal end and having a sharpened tissue piercing point on the needle distal end, the needle being adapted to be inserted into said cannula lumen, so that when said needle hub engages with said cannula hub, then the needle distal end will extend beyond said cannula distal end by a known length, and said needle and said cannula can be inserted together into bodily tissue so that said distal end of said needle is located at a target position in the bodily tissue,

A high-frequency electrode having an electrode shaft with an electrode distal end and an electrode proximal end, the electrode having an electrode hub at the electrode proximal end, and said electrode having a shaft portion that is adapted to be inserted into said cannula lumen, so that when said electrode hub engages with said cannula hub, then the portion of the electrode shaft that extends beyond the cannula distal end is uninsulated, and the electrode distal end extends beyond said cannula distal end by the same length as said known length,

A high-frequency generator adapted to produce an output signal, and for connection of the high-frequency generator to said electrode, and said electrode being adapted so that when connected to said high-frequency generator, said uninsulated extension portion of said electrode is connected to said output signal,

Whereby, when said cannula and said needle are inserted into bodily tissue so that said needle distal end is positioned at a target location within the bodily tissue, said needle can be removed with from said cannula, and said electrode can be inserted into said cannula so that said electrode distal end is located at the same target position in the bodily tissue, and then when said electrode is connected to said high-frequency generator, said output signal causes heating of the bodily tissue near said uninsulated extension portion of said electrode.

62. The system of claim 61, and further comprising a source of coolant fluid, and wherein said electrode comprises an internal fluid channel, a fluid input port and a fluid output port, the input and output ports being adapted to be connected to the source of coolant fluid so that the coolant fluid can flow into the input port, through the internal fluid channel, and out of the output port, and whereby said uninsulated portion of said electrode that extends beyond said cannula distal end is cooled by said coolant fluid.

63. The system of claim 61, wherein substantially all of the length of said electrode shaft has a conductive uninsulated surface.

64. The system of claim 61, wherein said cannula, and/or stylet, and/or electrode comprises ecogenic markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an ultrasonic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the structures in the patient'"'"'s body.

65. The system of claim 61, wherein said cannula, and/or stylet, and/or electrode comprises x-ray visible markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an x-ray, fluoroscopy, CT, or other radiographic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the structures in the patient'"'"'s body.

66. An electrode system adapted for introduction into bodily tissue comprising:

A cannula having an internal lumen and having a cannula shaft portion to be inserted into the living body, the shaft portion being substantially insulated, and a cannula shaft portion having a cannula distal end and a cannula proximal end, the cannula distal end having an opening that connects to the internal lumen, and the cannula proximal end being connected to a cannula hub;

An insertion needle that is adapted to be inserted into the internal lumen of the cannula, the insertion needle having a needle shaft portion that has a needle distal end and a needle proximal end, the needle distal end being adapted to pierce the tissue of the living body, and the needle proximal end being connected to a needle hub, and the needle shaft portion having a length so that when inserted into said internal lumen so that said cannula hub and said needle hub is in a determined needle hub position relative to said cannula hub, the assembly of said insertion needle within said cannula is adapted to be inserted into the tissue of the living body, and said needle distal end will extend beyond said cannula distal end by a determined extension distance greater 6 mm;

A high frequency electrode that is adapted to be inserted into said in internal lumen of said cannula, the high-frequency electrode having an electrode shaft portion that has an electrode distal end an electrode proximal end, the electrode proximal end being connected to an electrode hub, and the electrode shaft portion is substantially uninsulated, and the electrode shaft portion having a length so that when inserted into said internal lumen so that said cannula hub and said electrode hub is in a determined electrode hub position relative to said cannula hub, an uninsulated portion of said electrode shaft electrode extends beyond set cannula distal and said electrode distal end extends beyond said cannula distal end by said determined extension distance.

67. The system of claim 66, wherein said cannula, and/or stylet, and/or electrode comprises ecogenic markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an ultrasonic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the structures in the patient'"'"'s body.

68. The system of claim 66, wherein said cannula, and/or stylet, and/or electrode comprises x-ray visible markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an x-ray, fluoroscopy, CT, or other radiographic imaging can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the structures in the patient'"'"'s body.

69. A method for heating of bodily tissue comprising the following steps:

Selecting a cannula adapted to approach a target position in the bodily tissue, the cannula having a cannula distal end and a cannula proximal end, the cannula having a cannula hub at the cannula proximal end, said cannula having a cannula shaft having a lumen there-through, and the cannula shaft is substantially insulated, and said cannula having a known cannula length appropriate to approach the target position,

Selecting a tissue piercing needle and/or stylet having a needle shaft with a needle distal end and a needle proximal and, the needle having a needle hub at the needle proximal end and having a sharpened tissue piercing point on the needle distal end, the needle being adapted to be inserted into said cannula lumen, so that when said needle hub engages with said cannula hub, then the needle distal end will extend beyond said cannula distal end by a known length, and said needle and said cannula can be inserted together into bodily tissue so that said distal end of said needle is located at a target position in the bodily tissue,

Inserting a combination of said needle inserted into said cannula into the patient'"'"'s body to position the combination of said needle and said cannula into a clinically desired position near a target position in the bodily tissue.

Selecting a high-frequency electrode having an electrode shaft with an electrode distal end and an electrode proximal end, the electrode having an electrode hub at the electrode proximal end, and said electrode having a shaft portion that is adapted to be inserted into said cannula lumen, so that when said electrode hub engages with said cannula hub, then the portion of the electrode shaft that extends beyond the cannula distal end is uninsulated, and the electrode distal end extends beyond said cannula distal end by the same length as said known length,

Removing said needle from said cannula, and inserting said electrode into said cannula so that said portion of said electrode shaft that extends beyond said cannula distal end is at a desired position near a target position in the bodily tissue,

Connecting said electrode to a high-frequency generator adapted to produce an output signal, and said electrode being adapted so that when connected to said high-frequency generator, said uninsulated extension portion of said electrode is connected to said output signal,

Connecting said electrode to a source of coolant fluid, and wherein said electrode comprises an internal fluid channel, a fluid input port and a fluid output port, the input and output ports being adapted to be connected to the source of coolant fluid so that the coolant fluid can flow into the input port, through the internal fluid channel, and out of the output port, and whereby said uninsulated portion of said electrode that extends beyond said cannula distal end is cooled by said coolant fluid, and further including the step of flowing said coolant fluid through with said electrode,

Applying said output signal to said electrode to cause heating of the bodily tissue near said uninsulated extension portion of said electrode.

70. The method of claim 69 wherein,

There is a set of cannulas of different lengths adapted so that when said needle or said electrode is inserted into a specific cannula of said set of the cannulas, the known length of extension of said needle distal and or said electrode distal end is a specific known length,

And further including the step of selecting the appropriate said specific cannula from said set of cannulas so that said specific known length is appropriate the dimensions of the target volume within the bodily tissue to be heated.

71. The method of claim 69, wherein said cannula, and/or stylet, and or electrode comprises ecogenic markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an ultrasonic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the anatomical structures in the patient'"'"'s body, and further including the step of applying an ultrasonic imaging machine to the patient'"'"'s body to visualize the position of the ecogenic portions of said cannula, and/or stylet, and/or electrode within the patient'"'"'s body relative to anatomical structures in the patient'"'"'s body.

72. The method of claim 69, wherein said cannula, and/or stylet, and or electrode comprises x-ray visible markings at known positions on their shafts so that when the combination of said cannula and said stylet, or the combination of said cannula and said electrode are inserted into the patient'"'"'s body tissue, an x-ray, CT, fluoroscopic, or other radiographic imaging machine can be used to visualize the position of portions of said cannula, and/or said stylet, and/or said electrode relative to the anatomical structures in the patient'"'"'s body, and further including the step of applying an radiographic imaging machine to the patient'"'"'s body to visualize the position of the x-ray visible portions of said cannula, and/or stylet, and/or electrode within the patient'"'"'s body relative to anatomical structures in the patient'"'"'s body.