Shaped electrodes and methods for electrosurgical cutting and ablation
First Claim
1. An electrosurgical instrument for applying electrical energy to a target site on a structure within or on a patient'"'"'s body, the instrument comprising:
- a shaft having a proximal end and a distal end;
one or more active electrodes disposed near the distal end of the shaft, the active electrodes each having an active portion with a surface geometry configured to promote substantially high electric field intensities between the active portion and the target site when a high frequency voltage is applied to the electrodes, wherein the electric field intensities are sufficient to vaporize an electrically conducting liquid in contact with at least the active portion of the active electrodes; and
a connector disposed near the proximal end of the shaft for electrically coupling the electrodes to a high frequency voltage source.
3 Assignments
0 Petitions
Accused Products
Abstract
An electrosurgical system and method allow the surgical team to perform electrosurgical interventions, such as ablation and cutting of body structures, while limiting the depth of necrosis and limiting damage to tissue adjacent the treatment site. The system includes an electrosurgical probe having a shaft with a proximal end, a distal end, and at least one active electrode at or near the distal end. The active electrode includes at least one active portion having a surface geometry configured to promote substantially high electric field intensities and associated current densities between the active portion and the target site when a high frequency voltage is applied to the electrodes. These high electric field intensities and current densities are sufficient to break down the tissue by processes including molecular dissociation or disintegration. The high frequency voltage imparts energy to the target site to ablate a thin layer of tissue without causing substantial tissue necrosis beyond the boundary of the thin layer of tissue ablated. This ablative process can be precisely controlled to effect the volumetric removal of tissue as thin as a few layers of cells with minimal heating of or damage to surrounding or underlying tissue structures.
522 Citations
50 Claims
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1. An electrosurgical instrument for applying electrical energy to a target site on a structure within or on a patient'"'"'s body, the instrument comprising:
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a shaft having a proximal end and a distal end; one or more active electrodes disposed near the distal end of the shaft, the active electrodes each having an active portion with a surface geometry configured to promote substantially high electric field intensities between the active portion and the target site when a high frequency voltage is applied to the electrodes, wherein the electric field intensities are sufficient to vaporize an electrically conducting liquid in contact with at least the active portion of the active electrodes; and a connector disposed near the proximal end of the shaft for electrically coupling the electrodes to a high frequency voltage source. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
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19. An electrosurgical instrument for applying electrical energy to a target site on a structure within or on a patient'"'"'s body, the instrument comprising:
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a shaft having a proximal end and a distal end; at least one electrode disposed near the distal end of the shaft, the electrode having an exposed section with one or more active portions and one or more non-active portions; an electrically insulating material covering the non-active portions of the electrode to insulate the non-active portions from the target site and preferentially direct electrical current through the active portions; and a connector disposed near the proximal end of the shaft for electrically coupling the electrode to a high frequency voltage source. - View Dependent Claims (20, 21, 22, 23, 24, 25, 26)
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27. An electrosurgical system for use with a high frequency power supply and an electrically conducting fluid supply, the system comprising:
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an electrosurgical probe comprising a shaft having a proximal end and a distal end, one or more active electrodes disposed near the distal end, and a connector near the proximal end of the shaft for electrically coupling the active electrodes to the electrosurgical power supply, the active electrodes each having an active portion with a surface geometry configured to promote substantially high electric field intensities between the active portion and the target site when a high frequency voltage is applied to the electrodes, wherein the electric field intensities are sufficient to vaporize an electrically conducting liquid in contact with at least the active portion of the active electrodes; and a return electrode adapted to be electrically coupled to the electrosurgical power supply. - View Dependent Claims (28, 29, 30, 31)
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32. A method for applying electrical energy to a target site on a structure within or on a patient'"'"'s body, the method comprising:
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positioning an active portion of one or more active electrodes into at least close proximity with the target site in the presence of an electrically conductive fluid; applying high frequency voltage to the active electrodes and a return electrode such that an electrical current flows from the active electrode, through the body structure in the region of the target site, and to the return electrode; and generating substantially high, localized electric field intensities between the active portion of each active electrode and the target site. - View Dependent Claims (33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49)
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50. A method for applying electrical energy to a target site on a structure within or on a patient'"'"'s body, the method comprising:
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positioning an active portion of one or more active electrodes into at least close proximity with the target site in the presence of an electrically conducting fluid; applying high frequency voltage to the active electrode and a return electrode such that an electrical current flows from the active electrode to the return electrode; and generating electric field intensities between the active portion of each active electrode and the target site, the electric field intensities being sufficient to vaporize the fluid in contact with a portion of the active electrode.
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Specification