Electrosurgical instrument which reduces collateral damage to adjacent tissue
An electrode assembly for use in combination with an electrosurgical instrument having opposing end effectors and a handle for effecting movement of the end effectors relative to one another. The electrode assembly includes a housing having one portion which is removably engageable with the electrosurgical instrument and a pair of electrodes each having an electrically conductive sealing surface and an insulating substrate. The electrodes are removably engageable with the end effectors of the electrosurgical instrument such that the electrodes reside in opposing relation relative to one another. The dimensions of the insulating substrate are different from the dimensions of the electrically conductive sealing surface to reduce thermal spread to adjacent tissue structures.
1. An electrode assembly for use with an electrosurgical instrument having opposing end effectors and a handle for effecting movement of the end effectors relative to one another, comprising:
a housing having at least one portion that removably engages at least one portion of the electrosurgical instrument, the housing including a bifurcated distal end that forms two prongs that each removably attach to one of the end effectors; and
a pair of opposing electrodes each supported on one of the two prongs and each including an electrically conductive sealing surface defining a radius along an outer periphery thereof and a corresponding insulating substrate operably coupled to each sealing surface, each insulating substrate including a mechanical interface configured to removably couple the corresponding sealing surface to a respective opposing end effector such that the electrodes reside in opposing relation relative to one another,
wherein at least one of the electrically conductive sealing surfaces of one of the opposing electrodes is configured in a raised position relative to its corresponding insulating substrate such that the corresponding insulating substrate meets the outer periphery of the electrically conductive sealing surface to form an adjoining edge that tracks along the radius to reduce current concentrations between the opposing electrodes during activation.
2. An electrode assembly according to claim 1 , wherein the insulating substrate is selected from the group consisting of nylon, syndiotactic-polystryrene, polybutylene terephthalate, polycarbonate, acrylonitrile butadiene styrene, polyphthalamide, polymide, polyethylene terephthalate, polyamide-imide, acrylic, polystyrene, polyether sulfone, aliphatic polyketone, acetal copolymer, polyurethane, nylon with polyphenylene-oxide dispersion and acrylonitrile styrene acrylate.
3. An electrode assembly according to claim 1 , wherein the at least one raised electrically conductive sealing surface is radiused relative to the corresponding insulating substrate.
4. An electrode assembly according to claim 1 , wherein a radius of the outer periphery of the electrically conductive sealing surfaces ranges from about a ten thousandth of an inch to about a thirty thousandth of an inch.
5. An electrode assembly according to claim 1 , wherein the radius of the at least one raised electrically conductive sealing surface is different from a radius of another raised electrically conductive sealing surface.
6. An electrode assembly according to claim 1 , wherein the electrically conductive sealing surface of at least one electrode includes a pinch trim and the corresponding insulating substrate extends beyond a periphery of the electrically conductive sealing surface.
7. An electrode assembly for use with an electrosurgical instrument having a handle and at least one shaft for effecting movement of a pair of opposing end effectors relative to one another, comprising:
a housing having at least one portion that removably engages at least one of the handle and the shaft, the housing including a bifurcated distal end that forms two prongs that each removably attach to one of the end effectors; and
a pair of electrodes each supported on one of the two prongs and each having an electrically conductive sealing surface defining a radius along an outer periphery thereof and having a first geometric shape and a corresponding insulating substrate operably coupled to each sealing surface and having a second geometric shape, each insulating substrate including a mechanical interface configured to removably couple the corresponding sealing surface to a respective opposing end effector such that the electrodes reside in opposing relation relative to one another,
wherein each of the electrically conductive sealing surfaces of the electrodes is configured in a raised position relative to a corresponding insulative substrate such that the corresponding insulating substrate meets the outer periphery of the respective electrically conductive sealing surface to form an adjoining edge that tracks along the radius to reduce current concentrations between the opposing electrodes.
8. An electrode assembly according to claim 7 , wherein the at least one raised electrically conductive sealing surface is radiused relative to the corresponding insulating substrate.