Electrosurgical apparatus and methods for laparoscopy

• US 20030216725A1
• Filed: 02/14/2003
• Published: 11/20/2003
• Est. Priority Date: 05/10/1993
• Status: Active Grant

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Woloszko, Jean, Ellsberry, Maria
• Granted Patent: US 7,331,957 B2
• Time in Patent Office: Days
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• 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 18/1482 having a long rigid shaft for accessing the inner body transcutaneously in minimal invasive surgery, e.g. laparoscopy
• CPC Class Codes: A61B 18/1485 having a short rigid shaft for accessing the inner body through natural openings
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00583 Coblation, i.e. ablation using a cold plasma
• CPC Class Codes: A61B 2018/00601 Cutting
• CPC Class Codes: A61B 2018/1213 creating an arc
• CPC Class Codes: A61B 2018/1407 Loop
• CPC Class Codes: A61B 2018/144 Wire
• CPC Class Codes: A61B 2018/1467 using more than two electrodes on a single probe
• 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

Electrosurgical methods and apparatus for treating tissue at a target site of a patient. An electrosurgical instrument includes a shaft, having a shaft distal end and a shaft proximal end, and an electrode assembly disposed at the shaft distal end. The electrode assembly includes at least one active electrode disposed on an electrode support. The instrument is adapted for coupling to a high frequency power supply or electrosurgical generator. Each active electrode is adapted for removing tissue from a target site and/or for localized coagulation of the target tissue. In one embodiment, the instrument is adapted for laparoscopic procedures.

Claims

1. An electrosurgical apparatus for treating tissue at a target site, comprising:

a shaft having a shaft distal end and a shaft proximal end;

an electrically insulating electrode support disposed at the shaft distal end; and

a plurality of active electrodes disposed on the electrode support, wherein each of the plurality of active electrodes includes a bridge portion, and wherein the bridge portions are arranged substantially parallel to each other.

2. The apparatus of claim 1, wherein the plurality of active electrodes are unequal in size.

3. The apparatus of claim 1, wherein each of the plurality of active electrodes comprises a first filament and a second filament, and wherein the bridge portion is suspended between the first filament and the second filament.

4. The apparatus of claim 1, wherein each bridge portion includes a first distal face and a second distal face contiguous with the first distal face to define a distal edge.

5. The apparatus of claim 4, wherein the first distal face and the second distal face are arranged at an acute angle.

6. The apparatus of claim 1, wherein each bridge portion is oriented in substantially the same direction.

7. The apparatus of claim 1, wherein each of the plurality of active electrodes comprises a material selected from the group consisting of:

stainless steel, molybdenum, platinum, tungsten, palladium, iridium, titanium, and their alloys.

8. The apparatus of claim 1, wherein the electrode support includes a treatment surface, and wherein each bridge portion is spaced from the treatment surface by a minimum distance in the range of from about 0.05 mm to 3 mm.

9. The apparatus of claim 1, wherein the electrode support includes a treatment surface and a recess within the treatment surface.

10. The apparatus of claim 9, wherein each bridge portion spans the recess.

11. The apparatus of claim 9, wherein each bridge portion is arranged substantially orthogonal to the recess.

12. The apparatus of claim 9, further comprising an aspiration unit including an aspiration port, wherein the aspiration port is disposed within the recess.

13. The apparatus of claim 1, wherein the plurality of active electrodes comprise a first active electrode, a second active electrode, and a third active electrode, wherein the second active electrode is located between the first active electrode and the third active electrode, the bridge portion of the first active electrode and the bridge portion of the third active electrode are of substantially equal length, and the bridge portion of the second active electrode is longer than the bridge portion of the first active electrode.

14. The apparatus of claim 1, wherein the shaft distal end is curved.

15. The apparatus of claim 1, wherein the shaft includes an electrically conducting inner shaft and an electrically insulating outer shaft.

16. The apparatus of claim 1, further comprising a multi-lumen tube lying within the shaft, the multi-lumen tube including an aspiration lumen, the aspiration lumen coupled to a void within the electrode support.

17. The apparatus of claim 1, further comprising a fluid delivery unit including a plurality of fluid delivery channels, each of the plurality of fluid delivery channels lying external to the shaft distal end.

18. An electrosurgical apparatus, comprising:

a shaft having a shaft distal end and a shaft proximal end;

an electrically insulating electrode support disposed at the shaft distal end; and

a plurality of active electrodes disposed on the electrode support, wherein the electrode support includes a distal treatment surface and a recess within the treatment surface, wherein each of the plurality of active electrodes is arranged substantially orthogonal to the recess.

19. The apparatus of claim 18, wherein the recess bisects the treatment surface into two substantially equal parts.

20. The apparatus of claim 18, wherein the electrode support comprises a material selected from the group consisting of a ceramic, a glass, and a silicone rubber.

21. The apparatus of claim 18, wherein the treatment surface is substantially planar.

22. The apparatus of claim 21, wherein the treatment surface is arranged at an angle in the range of from about 25°

to 75°

with respect to the longitudinal axis of the shaft.

23. The apparatus of claim 18, further comprising an aspiration unit including an aspiration port, wherein the aspiration port lies within the recess.

24. The apparatus of claim 18, wherein each of the plurality of active electrodes includes a bridge portion, the bridge portions arranged substantially parallel to each other and the recess disposed substantially orthogonal to each bridge portion.

25. The apparatus of claim 24, wherein each of the plurality of active electrodes comprises a first filament and a second filament, and wherein the bridge portion is suspended between the first filament and the second filament.

26. The apparatus of claim 24, wherein each bridge portion is spaced from the treatment surface by a minimum distance in the range of from about 0.05 mm to 3 mm.

27. The apparatus of claim 24, wherein each bridge portion spans the recess.

28. An electrosurgical apparatus for treating tissue at a target site, comprising:

a shaft having a shaft distal end and a shaft proximal end;

an electrically insulating electrode support disposed at the shaft distal end; and

a plurality of active electrodes arranged substantially parallel to each other on the electrode support, wherein the shaft comprises an inner shaft and an outer shaft, wherein a proximal portion of the inner shaft lies within the outer shaft, and a distal portion of the inner shaft extends distally from the outer shaft.

29. The apparatus of claim 28, wherein the inner shaft comprises a metal tube.

30. The apparatus of claim 29, wherein the metal tube comprises stainless steel.

31. The apparatus of claim 29, wherein the metal tube has a curved distal end.

32. The apparatus of claim 28, wherein the outer shaft comprises an electrically insulating tube.

33. The apparatus of claim 32, wherein the outer shaft comprises a composite material, the composite material including a resin.

34. The apparatus of claim 33, wherein the composite material further includes a fibrous material.

35. The apparatus of claim 28, further comprising an electrically insulating sleeve ensheathing a length of the inner shaft, wherein the inner shaft includes at least one longitudinal, external groove.

36. The apparatus of claim 28, further comprising a return electrode.

37. The apparatus of claim 36, wherein the return electrode comprises an exposed, distal portion of the inner shaft.

38. The apparatus of claim 28, further comprising a fluid delivery unit.

39. The apparatus of claim 38, wherein the fluid delivery unit comprises a plurality of fluid delivery channels, each fluid delivery channel defined jointly by an external groove in the inner shaft and an inner surface of an electrically insulating sleeve, the sleeve ensheathing a length of the inner shaft.

40. The apparatus of claim 28, wherein each of the plurality of active electrodes comprises a first filament, a second filament, and a bridge portion suspended between the first filament and the second filament.

41. The apparatus of claim 28, wherein each of the plurality of active electrodes including a distal edge, wherein the distal edge is characterized by an acute angle in the range of from about 25°

to 85°

.

42. The apparatus of claim 40, wherein the electrode support includes a substantially planar treatment surface, and wherein each bridge portion is spaced from the treatment surface by a minimum distance in the range of from about 0.05 mm to 3 mm.

43. The apparatus of claim 40, wherein the electrode support includes a treatment surface and a recess within the treatment surface, and each bridge portion spans the recess.

44. The apparatus of claim 43, wherein the treatment surface is bisected by the recess.

45. The apparatus of claim 28, wherein the electrode support comprises a ceramic.

46. The apparatus of claim 43, further comprising an aspiration unit adapted for aspirating excess or unwanted materials from a working end of the apparatus or from a surgical site.

47. The apparatus of claim 46, wherein the aspiration unit includes an aspiration port, and wherein the aspiration port lies within the recess.

48. The apparatus of claim 28, further comprising a connection block adapted for coupling the plurality of active electrodes to a high frequency power supply, wherein each of the plurality of active electrodes comprises a bridge portion, a first filament, and a second filament, and wherein at least one of the first filament and the second filament is coupled to the connection block.

49. An electrosurgical instrument, comprising:

a shaft having a shaft distal end, the shaft distal end having a plurality of longitudinal, external grooves;

an electrode assembly disposed at the shaft distal end; and

an electrically insulating sheath external to the shaft distal end, the sheath and the plurality of grooves jointly defining a corresponding plurality of fluid delivery channels external to the shaft distal end, each of the plurality of fluid delivery channels adapted as a fluid conduit.

50. The instrument of claim 49, wherein the electrically insulating sheath comprises a heat shrink tube.

51. The instrument of claim 49, wherein the electrode assembly comprises an electrically insulating electrode support having a treatment surface, and at least one active electrode disposed on the treatment surface.

52. The instrument of claim 51, wherein each active electrode includes a distal edge, each distal edge characterized as having an acute angle.

53. The instrument of claim 49, wherein the shaft distal end is curved.

54. An electrosurgical instrument, comprising:

a shaft having a shaft distal end and a shaft proximal end;

an electrically insulating electrode support disposed at the shaft distal end, the electrode support including a treatment surface and a linear recess within the treatment surface;

an aspiration unit including an aspiration port, the aspiration port lying within the recess; and

a plurality of active electrodes disposed on the electrode support, each of the plurality of active electrodes comprising a bridge portion, each bridge portion bridging the recess.

55. The instrument of claim 54, wherein the bridge portions are arranged substantially parallel to each other.

56. The instrument of claim 55, wherein the recess bisects the treatment surface, the bridge portions span the recess, and each bridge portion is arranged substantially orthogonal to the recess.

57. The instrument of claim 56, wherein the bridge portions of the plurality of active electrodes are of unequal length.

58. An electrode assembly for an electrosurgical probe, the electrode assembly comprising:

an electrically insulating electrode support having a treatment surface; and

an electrode array comprising a plurality of active electrodes, wherein each of the plurality of active electrodes comprises a bridge portion spaced from the treatment surface, and wherein the bridge portions are arranged substantially parallel to each other.

59. The electrode assembly of claim 58, wherein the bridge portion further comprises a first distal face and a second distal face, the second distal face contiguous with the first distal face to define a distal edge.

60. The electrode assembly of claim 59, wherein the first distal face and the second distal face are configured at an acute angle.

61. The electrode assembly of claim 59, wherein the first distal face and the second distal face are configured at an angle in the range of from about 25°

to 85°

.

62. The electrode assembly of claim 58, wherein each of the plurality of active electrodes protrudes from the electrode support at an acute angle to the treatment surface.

63. The electrode assembly of claim 58, wherein each of the plurality of active electrodes protrudes from the electrode support at an angle in the range of from about 60°

to 85°

with respect to the treatment surface.

64. The electrode assembly of claim 58, wherein each of the plurality of active electrodes comprises a first filament and a second filament, the bridge portion suspended between the first filament and the second filament.

65. The electrode assembly of claim 64, wherein the bridge portion is substantially orthogonal to both the first filament and the second filament.

66. The electrode assembly of claim 64, wherein the bridge portion has a cross-sectional area greater than that of the first filament or the second filament.

67. The electrode assembly of claim 58, wherein the bridge portion of each of the plurality of active electrodes is spaced from the treatment surface by a minimum distance in the range of from about 0.05 mm to 3 mm.

68. The electrode assembly of claim 58, wherein the electrode array comprises a first active electrode, a second active electrode and a third active electrode, wherein the second active electrode is located between the first active electrode and the third active electrode.

69. The electrode assembly of claim 68, wherein the bridge portions of the first and third active electrodes are of substantially equal length.

70. The electrode assembly of claim 69, wherein the bridge portion of the second active electrode is longer than the bridge portion of the first active electrode.

71. The electrode assembly of claim 58, wherein the electrode support includes a recess, the recess bisecting the treatment surface.

72. The electrode assembly of claim 71, wherein the electrode support further includes a void disposed within the recess, the void defining an aspiration port.

73. The electrode assembly of claim 71, wherein the recess is linear, and each bridge portion is substantially orthogonal to the recess.

74. An electrosurgical system, comprising:

an electrosurgical instrument; and

a high frequency power supply coupled to the instrument for applying a high frequency voltage to the instrument, the instrument including;

a shaft having a shaft distal end and a shaft proximal end;

an electrically insulating electrode support disposed at the shaft distal end, the electrode support including a treatment surface and a recess within the treatment surface; and

a plurality of active electrodes protruding from the treatment surface, each of the plurality of active electrodes coupled to the high frequency power supply, each of the plurality of active electrodes comprising a bridge portion, the bridge portions arranged substantially parallel to each other, and at least one of the bridge portions spanning the recess.

75. The system of claim 74, wherein the electrosurgical instrument further includes an aspiration unit including an aspiration port, the aspiration port lying within the recess.

76. The system of claim 74, wherein each of the plurality of active electrodes is independently coupled to a separate channel of the high frequency power supply.

77. The system of claim 74, wherein the high frequency power supply is adapted for operation in the ablation mode and the sub-ablation mode.

78. The system of claim 74, wherein the bridge portion of each of the plurality of active electrodes spans the recess, and each bridge portion is arranged substantially orthogonal to the recess.

79. The system of claim 75, wherein at least one of the plurality of active electrodes spans the aspiration port.

80. A method of treating tissue at a target site of a patient, comprising:

a) positioning a working end of an electrosurgical instrument in the vicinity of the target site, the working end bearing an electrically insulating electrode support, the electrode support including a treatment surface, and a plurality of active electrodes disposed on the treatment surface, each of the plurality of active electrodes including a bridge portion, the bridge portions arranged substantially parallel to each other, wherein at least one of the bridge portions makes contact with, or is in close proximity to, the tissue at the target site; and

b) applying a high frequency voltage between the plurality of active electrodes and a return electrode, wherein at least a portion of the tissue at the target site is ablated or modified.

81. The method of claim 80, wherein the high frequency voltage of said step b) is an ablation voltage effective in removing the tissue in a controlled manner.

82. The method of claim 80, wherein the high frequency voltage of said step b) is a sub-ablation voltage effective in coagulating the tissue.

83. The method of claim 80, further comprising:

c) prior to or during said step b), delivering an electrically conductive fluid to the working end of the instrument or to the target site, wherein the electrically conductive fluid provides a current flow path between at least one of the plurality of active electrodes and the return electrode.

84. The method of claim 80, further comprising:

d) aspirating unwanted materials from the vicinity of the target site.

85. The method of claim 80, wherein the voltage applied in said step b) effects ablation of the tissue at the target site to a controlled depth with little or no damage to adjacent or underlying tissue.

86. The method of claim 81, wherein the tissue at the target site comprises ectopic endometrial tissue, and the voltage applied in said step b) is effective in removing the ectopic endometrial tissue from an underlying delicate tissue or organ, with little or no damage to the underlying delicate tissue or organ.

87. The method of claim 80, further comprising:

e) manipulating the instrument such that the plurality of active electrodes are moved with respect to the tissue at the target site.

88. The method of claim 80, wherein each of the plurality of active electrodes includes a distal edge, and the method further comprises:

f) moving each distal edge with respect to the tissue, wherein the tissue is ablated in a region of movement of each distal edge.

89. The method of claim 80, wherein the high frequency voltage applied in said step b) is in the range of from about 10 volts RMS to 1000 volts RMS.

90. A method of treating a target tissue of a patient, comprising:

a) providing an electrosurgical probe, the probe including an electrode array comprising a plurality of active electrodes, each of the plurality of active electrodes including a bridge portion, the electrode array configured such that each of the bridge portions are substantially parallel with each other;

b) positioning the electrode array in at least close proximity to the target tissue; and

c) applying a high frequency voltage between a return electrode and the plurality of active electrodes, wherein the voltage is effective in ablating or modifying the target tissue.

91. The method of claim 90, wherein the voltage applied in said step c) is an ablation voltage in the range of from about 200 volts RMS to 1000 volts RMS.

92. The method of claim 90, wherein the voltage applied in said step c) is a sub-ablation voltage in the range of from about 10 volts RMS to 150 volts RMS.

93. The method of claim 90, wherein each of the plurality of active electrodes is adapted for digesting resected tissue fragments, and the method further comprises:

d) during said step c), vaporizing the resected tissue fragments.

94. The method of claim 90, wherein the target tissue comprises ectopic endometrial tissue.

95. The method of claim 90, further comprising:

e) during said step c), manipulating the probe such that the electrode array is translated with respect to the target tissue.

96. The method of claim 90, wherein said step b) involves accessing the target tissue in a laparoscopic procedure.

97. The method of claim 90, wherein said step b) involves introducing a working end of the probe into the patient via a cannula having a diameter of 5 mm or less.

98. The method of claim 90, wherein the probe further includes an aspiration unit adapted for aspirating unwanted or excess materials from a surgical site, and the method further comprises:

f) aspirating the unwanted or excess materials in an aspiration stream via the aspiration unit.

99. The method of claim 98, wherein said step f) comprises aspirating gaseous ablation by-products from the vicinity of the target tissue.

100. A method of treating a target tissue of a patient, comprising:

a) advancing a shaft distal end of an electrosurgical instrument towards the target tissue, the shaft distal end having an electrode assembly disposed thereon, the electrode assembly comprising an electrode support and a plurality of active electrodes disposed on the electrode support, the electrode support having a treatment surface and a recess bisecting the treatment surface, each of the plurality of active electrodes adapted for coagulating or ablating the target tissue; and

b) applying a high frequency voltage between a return electrode and each of the plurality of active electrode terminals, wherein the target tissue is coagulated or ablated with minimal or no collateral damage to adjacent non-target tissue.

101. The method of claim 100, wherein the target tissue comprises ectopic endometrial tissue.

102. The method of claim 100, wherein the depth to which the target tissue is ablated can be precisely controlled.

103. The method of claim 100, further comprising:

c) as a result of said step b), resecting tissue fragments from the target tissue; and

d) via at least one of the plurality of active electrodes, at least partially digesting the resected tissue fragments.

104. The method of claim 100, further comprising:

e) after or during said step b), aspirating excess or unwanted materials from a surgical site via an aspiration unit, wherein the aspiration unit is integral with the electrosurgical instrument.

105. A method of electrosurgically removing ectopic endometrial tissue of a patient, the method comprising:

a) providing an electrosurgical probe, the probe including an electrode assembly having at least one active electrode;

b) positioning the electrode assembly in at least close proximity to a target endometrial implant; and

c) applying a high frequency voltage between a return electrode and the at least one active electrode, wherein the voltage is effective in removing the endometrial implant with little or no damage to tissue underlying the endometrial implant.

106. The method of claim 105, wherein the electrode assembly includes a plurality of active electrodes, and wherein said step b) comprises positioning at least one of the plurality of active electrodes in at least close proximity to the endometrial implant.

107. The method of claim 105, wherein said step b) comprises advancing a working end of the probe towards the endometrial implant via a laparoscope.

108. The method of claim 105, wherein said step b) comprises advancing a working end of the probe towards the bowel, the ureter, the urinary bladder, or the ovaries of the patient.

109. The method of claim 106, wherein each of the plurality of active electrodes includes a bridge portion, the electrode assembly configured such that each of the bridge portions are substantially parallel to each other, and wherein the electrode assembly is adapted for the removal of soft tissue in a controlled manner.

110. The method of claim 105, wherein the voltage applied in said step c) is effective in vaporizing the endometrial implant to form gaseous ablation by-products.

111. The method of claim 110, wherein the probe provided in said step a) includes an integral aspiration unit, and the method further comprises:

d) aspirating the gaseous ablation by-products from the vicinity of the target endometrial implant via the aspiration unit.