Methods and systems for focused bipolar tissue ablation

• US 7,387,628 B1
• Filed: 09/15/2000
• Issued: 06/17/2008
• Est. Priority Date: 09/15/2000
• Status: Expired due to Fees

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Huang, Alexander L., Behl, Robert S., Grosser, Morton
• Primary Examiner(s): Cohen; Lee S.
• Application Number:
  US09/663,048
• Time in Patent Office: 2,832 Days
• Field of Search: 606/32, 606/34, 606/37, 606/42, 606 45- 50, 607/96, 607/98, 607/99, 607/101, 607/104, 607/105, 607/106, 607/113
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1477 Needle-like probes
• CPC Class Codes: A61B 2018/0016 Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/143 multiple needles
• CPC Class Codes: A61B 2018/1432 curved
• CPC Class Codes: A61B 2018/1467 using more than two electrodes on a single probe

Abstract

Large tissue regions are treated using pairs of electrode arrays. The electrode arrays may be concave and disposed in tissue so that their concave portions are opposed to each other. Axial conductors may be provided extending from the arrays and toward each other in order to increase the heating of tissues lying along the axis between the deployed electrode arrays. By properly spacing the electrode arrays apart and selecting the diameters of the arrays, desired volumes of tissue may be treated, typically with a bipolar, radiofrequency current.

Claims

1. A probe for deploying electrode arrays, comprising:

a shaft having a distal end and a proximal end;

a first array of electrodes mounted on the shaft and configured to shift between a retracted configuration and a deployed configuration having a concave face; and

a second array of electrodes mounted on the shaft at a location spaced-apart proximally from the first array of electrodes, wherein the second electrode array is configured to shift between a retracted and a deployed configuration having a concave face;

wherein the concave face of the first electrode array faces the concave face of the second electrode array when the arrays are deployed, and the deployed first and second electrode arrays are configured to necrose a volume of tissue therebetween when electrical energy is applied between the first and second electrode arrays.

2. A probe as in claim 1, wherein the first and second electrode arrays each comprise a plurality of individual electrodes which initially move axially and then evert as they are deployed.

3. A probe as in claim 1, wherein the shaft has a self-penetrating tip.

4. A probe as in claim 1, wherein the shaft has at least one cavity for receiving the first and second electrode arrays when retracted.

5. A probe as in claim 1, wherein the shaft has at least one cavity for receiving the first electrode array when retracted and at least a second cavity for receiving the second electrode array when retracted.

6. A probe as in claim 1, further comprising:

a first rod connected to the first electrode array and slidably disposed in the shaft, wherein distal advancement of the first rod relative to the shaft causes the first electrode array to deploy distally; and

a second rod connected to the second electrode array and slidably disposed in the shaft, wherein proximal retraction of the second rod relative to the shaft causes the second electrode array to deploy proximally.

7. A probe as in claim 1, wherein the first electrode array spans a planar area in the range between 3 cm² to 20 cm² when deployed, the second electrode array spans a planar area in the range between 3 cm² and 20 cm² when deployed, and the first and second areas are spaced-apart along a line between their respective centers by a distance in the range between 2 cm to 10 cm.

8. A probe as in claim 1, further comprising a first axial conductor extending proximally along the shaft from the first electrode array to a location distal to the second electrode array, the first axial conductor being electrically coupled to the first electrode array.

9. A probe as in claim 8, wherein the first axial conductor extends proximally beyond the proximal terminus of the first electrode array so that the first axial conductor lies closer to the second electrode array than does any portion of the first electrode array.

10. A probe as in claim 8, further comprising a second axial conductor extending distally along the shaft from the second electrode array to a location proximal to the first axial conductor so that a gap exists between the first and second axial conductors, the second axial conductor being electrically coupled to the second electrode array.

11. A probe as in claim 10, wherein the second axial conductor extends distally beyond the distal terminus of the second electrode array so that the second axial conductor lies closer to the first electrode array than does any portion of the second electrode array.

12. A probe as in claim 10, wherein the distance between the inner termini of the first and second axial conductors is from 0.25 to 0.75 of the distance between the inner termini of the innermost portions of the first and second electrode arrays.

13. A probe as in claim 1, wherein the first electrode array and second electrode array are electrically isolated from each other, further comprising a first connector for connecting the first electrode array to one pole of a power supply and a second connector for connecting the second electrode array to a second pole of a power supply.

14. A probe as in claim 1, wherein the first and second electrode arrays are configured to necrose the volume of tissue axially outward from a center of the volume of tissue.

15. A probe as in claim 1, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is defined by outward perimeters of the first and second electrode arrays.

16. A probe as in claim 1, wherein the entire lengths of the electrodes of the first and second arrays are uninsulated.

17. A probe as in claim 1, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is at least 30 cm³.

18. A probe as in claim 1, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is at least 70 cm³.

19. A probe as in claim 1, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is at least 150 cm³.

20. A probe as in claim 1, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is within the range of 30-150 cm³.

21. A probe as in claim 1, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is within the range of 50-70 cm³.

22. A probe as in claim 1, wherein the first and second electrode arrays are completely spaced apart in the axial direction when in the deployed configuration.

23. A probe as in claim 1, wherein the concave face of the first electrode array points in the distal direction, and the concave face of the second electrode array points in the proximal direction when in the deployed configuration.

24. A probe as in claim 23, wherein the first electrode array deploys from a proximal axial location of the shaft, and the second electrode array deploys from a distal axial location of the shaft.

25. A probe as in claim 23, wherein the concave face of the first electrode array is proximal to the concave face of the second electrode array when in the deployed configuration.

26. A method for treating a treatment region in tissue, comprising:

deploying a first array of electrodes in tissue on one side of the treatment region, wherein the first electrode array has a concave face;

deploying a second array of electrodes in tissue along an axis with the first electrode array on another side of the treatment region, wherein the second electrode array has a concave face wherein the concave face of the first electrode array faces the concave face of the second electrode array when the arrays are deployed;

applying electrical energy between the deployed first and second electrode arrays to necrose the tissue region therebetween.

27. A method as in claim 26, wherein deploying the first electrode array comprises introducing a first probe through tissue to a location on one side of the treatment region and advancing a first plurality of at least three electrodes from the probe in an everting pattern.

28. A method as in claim 27, wherein deploying the second electrode array comprises advancing a second plurality of at least three electrodes from the probe in an everting pattern at a location on the other side of the treatment region.

29. A method as in claim 27, wherein deploying the second electrode array comprises introducing a second probe through tissue to a location on the other side of the treatment region and advancing a plurality of at least three electrodes in an everting pattern.

30. A method as in any of claims 26-29, wherein the tissue is selected from the group consisting of liver, lung, kidney, pancreas, stomach, uterus, and spleen.

31. A method as in any of claims 26-29, wherein the treatment region is a tumor.

32. A method as in claim 26, wherein electrical current is applied at a frequency in the range from 300 kHz to 1.2 MHz.

33. A method as in claim 26, wherein electrical current is applied at a power in the range from 50W to 300W.

34. A method as in any of claims 26-29, wherein the first and second electrode arrays each span a planar area in the range between 3 cm² to 20 cm², and wherein the first and second electrode arrays are spaced-apart along a line between their respective centers by a distance in the range between 2 cm to 10 cm.

35. A method as in any of claims 26-29, wherein the first electrode array includes a first axial conductor extending at least part of the way to the second electrode array along the axis therebetween.

36. A method as in claim 35, wherein the first axial conductor extends proximally beyond the proximal terminus of the first electrode array so that the first axial conductor lies closer to the second electrode array than does any portion of the first electrode array.

37. A method as in claim 35, wherein the second electrode array includes a second axial conductor extending part of the way to the first electrode array along the axis therebetween and wherein there is a gap between termini of the first axial conductor and the second axial conductor.

38. A method as in claim 37, wherein the second axial conductor extends distally beyond the distal terminus of the second electrode array so that the second axial conductor lies closer to the first electrode array than does any portion of the second electrode array.

39. A method as in claim 38, wherein the distance between inner termini of the first and second axial conductors is from 0.25 to 0.75 of the distance between the inner termini of the innermost portions of the first and second electrode arrays.

40. A method as in claim 26, wherein applying the electrical current comprises coupling one pole of a radiofrequency power supply to the first electrode array and another pole of the radiofrequency power supply to the second electrode array and energizing the power supply.

41. A method as in claim 26, wherein the tissue region is necrosed axially outward from a center of the tissue region.

42. A method as in claim 26, wherein the necrosed volume of tissue is defined by outward perimeters of the first and second electrode arrays.

43. A method as in claim 26, wherein the entire lengths of the electrodes of the first and second arrays are uninsulated.

44. A method as in claim 26, wherein the necrosed volume of tissue is at least 30 cm³.

45. A method as in claim 26, wherein the necrosed volume of tissue is at least 70 cm³.

46. A method as in claim 26, wherein the necrosed volume of tissue is at least 150 cm³.

47. A method as in claim 26, wherein the necrosed volume of tissue is within the range of 30-150 cm³.

48. A method as in claim 26, wherein the necrosed volume of tissue is within the range of 50-70 cm³.

49. A method as in claim 26, wherein the deployed first and second electrode arrays are completely spaced apart in the axial direction.

50. A method as in claim 26, wherein the concave face of the first electrode array points in the distal direction, and the concave face of the second electrode array points in the proximal direction when the first and second electrode arrays are deployed.

51. A method as in claim 50, wherein first electrode array deploys from an axial location that is proximal to an axial location from which the second electrode array deploys.

52. A method as in claim 50, wherein the concave face of the first electrode array is proximal to the concave face of the second electrode array when the first and second electrode arrays are deployed.

53. A method for bipolar radiofrequency necrosis of tissue, comprising:

deploying a first array of electrodes in tissue on one side of a treatment region, wherein the first electrode array has a concave face and an axial conductor extending in an axial direction from the concave face;

deploying a second array of electrodes in tissue on another side of the treatment region spaced-apart from the first electrode array, wherein the second electrode array has a concave face and an axial conductor extending in an axial direction opposed to the axial conductor on the first electrode array and wherein the concave face of the first electrode array faces the concave face of the second electrode array when the arrays are deployed; and

applying radiofrequency current to the tissue between the deployed first and second electrode arrays to necrose the tissue.

54. A method as in claim 53, wherein deploying the concave face of the first electrode array comprises introducing a first probe through tissue to a location on one side of the treatment region and advancing a first plurality of at least three electrodes from the probe in a radially diverging pattern.

55. A method as in claim 54, wherein the diverging pattern is everting.

56. A method as in claim 54 or 55, wherein deploying the concave second electrode array comprises advancing a second plurality of at least three electrodes from the probe in a radially diverging pattern at a location on the other side of the treatment region.

57. A method as in claim 56, wherein the diverging pattern is everting.

58. A method as in claim 54 or 55, wherein deploying the concave face of the second electrode array comprises introducing a second probe through tissue to a location on the other side of the treatment region and advancing a plurality of at least three electrodes in a radially diverging pattern.

59. A method as in claim 58, wherein the diverging pattern is everting.

60. A method as in claims 53, 54, or 55, wherein the tissue is selected from the group consisting of liver, lung, kidney, pancreas, stomach, uterus, and spleen.

61. A method as in claim 60, wherein the treatment region comprises a tumor lesion.

62. A method as in claim 53, wherein the radiofrequency current is applied at a frequency in the range from 300 kHz to 1.2 MHz.

63. A method as in claim 53, wherein the radiofrequency current is applied at a power in the range from 50W to 300W.

64. A method as in claims 53, 54, or 55, wherein applying the radiofrequency current comprises coupling one pole of a radiofrequency power supply to the first electrode array and another pole of the radiofrequency power supply to the second electrode array and energizing the power supply.

65. A method as in claims 53, 54, or 55, wherein the concave face of the first electrode array spans a planar area in the range between 3 cm² to 20 cm², the concave face of the second electrode array spans a planar area in the range between 3 cm and 20 cm², and the first and second electrode arrays are spaced-apart along an axial line between their respective centers by a distance in the range between 2 cm and 10 cm.

66. A method as in claim 65, wherein the termini of axial conductors of the first and second electrode arrays are spaced-apart in the axial direction by a distance in the range between 0.5 cm and 5 cm.

67. A method as in claim 53, wherein the distance between the termini of the first and second axial conductors is from 0.25 to 0.75 of the distance between the inner termini of the innermost portions of the first and second electrode arrays.

68. A method as in claim 53, wherein the tissue is necrosed axially outward from a center of the tissue region.

69. A method as in claim 53, wherein the necrosed tissue is defined by outward perimeters of the first and second electrode arrays.

70. A method as in claim 53, wherein the entire lengths of the electrodes of the first and second arrays are uninsulated.

71. A method as in claim 53, wherein the necrosed tissue has a volume of at least 30 cm³.

72. A method as in claim 53, wherein the necrosed tissue has a volume of at least 70 cm³.

73. A method as in claim 53, wherein the necrosed tissue has a volume of at least 150 cm³.

74. A method as in claim 53, wherein the necrosed tissue has a volume within the range of 30-150 cm³.

75. A method as in claim 53, wherein the necrosed tissue has a volume within the range of 50-70 cm³.

76. A method as in claim 53, wherein the deployed first and second electrode arrays are completely spaced apart in the axial direction.

77. A method as in claim 53, wherein the concave face of the first electrode array points in the distal direction, and the concave face of the second electrode array points in the proximal direction when the first and second electrode arrays are deployed.

78. A method as in claim 77, wherein first electrode array deploys from an axial location that is proximal to an axial location from which the second electrode array deploys.

79. A method as in claim 77, wherein the concave face of the first electrode array is proximal to the concave face of the second electrode array when the first and second electrode arrays are deployed.

80. A probe for deploying electrode arrays, comprising:

a shaft having a distal end and a proximal end;

a first array of electrodes mounted on the shaft and configured to shift between a retracted configuration and a deployed configuration having a concave face; and

a second array of electrodes mounted on the shaft at a location spaced-apart proximally from the first array of electrodes, wherein the second electrode array is configured to shift between a retracted and a deployed configuration having a concave face;

wherein the concave face of the first electrode array faces the concave face of the second electrode array when the arrays are deployed, and the deployed first and second electrode arrays are configured to necrose a volume of tissue therebetween when electrical energy is applied between the first and second electrical arrays.

81. A probe as in claim 80, wherein the first and second electrode arrays each comprise a plurality of individual electrodes which initially move axially and then evert as they are deployed.

82. A probe as in claim 80, wherein the shaft has a self-penetrating tip.

83. A probe as in claim 80 or 82, wherein the shaft has at least one cavity for receiving the first and second electrode arrays when retracted.

84. A probe as in claim 80 or 82, wherein the shaft has at least one cavity for receiving the first electrode array when retracted and at least a second cavity for receiving the second electrode array when retracted.

85. A probe as in claim 80 or 82, further comprising:

a first rod connected to the first electrode array and slidably disposed in the shaft, wherein distal advancement of the first rod relative to the shaft causes the first electrode array to deploy distally; and

a second rod connected to the second electrode array and slidably disposed in the shaft, wherein proximal retraction of the second rod relative to the shaft causes the second electrode array to deploy proximally.

86. A probe as in claim 85, wherein the first and second rods may be deployed separately.

87. A probe as in claim 80 or 82, wherein the first electrode array spans a planar area in the range between 3 cm² to 20 cm² when deployed, the second electrode array spans a planar area in the range between 3 cm² and 20 cm² when deployed, and the first and second areas are spaced-apart along a line between their respective centers by a distance in the range between 2 cm to 10 cm.

88. A probe as in claim 80 or 82, wherein the first electrode array and second electrode array are electrically isolated from each other, further comprising a first connector for connecting the first electrode array to one pole of a power supply and a second connector for connecting the second electrode array to a second pole of a power supply.

89. A probe as in claim 88, further comprising a first axial conductor extending proximally along the shaft from the first electrode array to a location distal to the second electrode array, the first axial conductor being electrically coupled to the first electrode array.

90. A probe as in claim 89, wherein the first axial conductor extends proximally beyond the proximal terminus of the first electrode array so that the first axial conductor lies closer to the second electrode array than does any portion of the first electrode array.

91. A probe as in claim 89, further comprising a second axial conductor extending distally along the shaft from the second electrode array to a location proximal to the first axial conductor so that a gap exists between the termini of the first and second axial conductors, the second axial conductor being electrically coupled to the second electrode array.

92. A probe as in claim 91, wherein the second axial conductor extends distally beyond the distal terminus of the second electrode array so that the second axial conductor lies closer to the first electrode array than does any portion of the second electrode array.

93. A probe as in claim 91, wherein the distance between the inner termini of the first and second axial conductors is from 0.25 to 0.75 of the distance between the inner termini of the innermost portions of the first and second electrode arrays.

94. A probe as in claim 80, wherein the first electrode array is electrically isolated from the second electrode array to permit the arrays to be connected to a power supply for bipolar operation.

95. A probe as in claim 80, wherein the first and second electrode arrays are configured to necrose the volume of tissue axially outward from a center of the volume of tissue.

96. A probe as in claim 80, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is defined by outward perimeters of the first and second electrode arrays.

97. A probe as in claim 80, wherein the entire lengths of the electrodes of the first and second arrays are uninsulated.

98. A probe as in claim 80, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is at least 30 cm³.

99. A probe as in claim 80, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is at least 70 cm³.

100. A probe as in claim 80, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is at least 150 cm³.

101. A probe as in claim 80, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is within the range of 30-150 cm³.

102. A probe as in claim 80, wherein the volume of tissue configured to be necrosed by the first and second electrode arrays is within the range of 50-70 cm³.

103. A probe as in claim 80, wherein the first and second electrode arrays are completely spaced apart in the axial direction when in the deployed configuration.

104. A probe as in claim 80, wherein the concave face of the first electrode array points in the distal direction, and the concave face of the second electrode array points in the proximal direction when in the deployed configuration.

105. A probe as in claim 104, wherein the first electrode array deploys from a proximal axial location of the shaft, and the second electrode array deploys from a distal axial location of the shaft.

106. A probe as in claim 104, wherein the concave face of the first electrode array is proximal to the concave face of the second electrode array when in the deployed configuration.