ILLUMINATED AND ISOLATED ELECTROSURGICAL APPARATUS
Unintended current flow or plasma discharge has been observed in known illuminated electrosurgical devices having a metallic tubular heat sink surrounding a conductive electrode and an illumination element, and having a distal outer edge that abuts against the light emitting element. An insulating, shielding or other isolating element that prevents or discourages unintended plasma formation between the distal outer edge and nearby patient tissue can reduce the potential for tissue damage to a patient or injury to a surgeon.
This application claims priority to U.S. Provisional Application No. 62/531,188 filed Jul. 11, 2017, the entire disclosure of which is incorporated herein by reference.
TECHNICAL FIELDThe present application relates to illuminated electrosurgical devices.
BACKGROUNDIlluminated electrosurgical devices generally include a hand piece (handle) ergonomically adapted for ease of manipulation by a surgeon during surgery, and for positioning an energy tip of the device to deliver electrical energy to a target tissue for tissue cutting or coagulation. An electrode and electrical supply cable are generally disposed within the handle, traversing from the handle's proximal end through the handle body, and terminating in an energy discharge tip at the distal end of the device. The electrical supply cable typically is connected to an energy source, such as a radiofrequency (RF) energy generator.
The handle or other portion of the device may include an illumination element for illuminating the surgical field. Light may be conducted towards the energy discharge tip and directed onto the surgical field via an optical waveguide coupled to the handle or disposed within the handle. The electrode may be disposed within the optical waveguide, or disposed alongside the waveguide. The electrode and waveguide may be disposed within a suitable supporting structure (for example, a cylindrical metal tube), that may be slidably extendable or retractable to permit the electrosurgical device to elongate or shorten as needed to treat the surgical site.
SUMMARYThe present invention provides an improved illuminated electrosurgical device having reduced tendency to cause unintended current flow or plasma discharge and patient injury. In one embodiment, the device comprises:
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- a) a handle;
- b) a conductive electrode supported by the handle and having a tip for cutting or cauterizing tissue;
- c) an illumination element coupled to the handle, the illumination element comprising a light source, an optical waveguide, and a light emitting element illuminating the electrode tip;
- d) a metallic tubular heat sink surrounding at least part of the conductive electrode and illumination element and having a distal outer edge that abuts against the light emitting element; and
- e) an insulating, shielding or other isolating element that prevents or discourages unintended current flow or plasma formation between the distal outer edge and nearby patient tissue.
The disclosed invention addresses shortcomings in current electrosurgical devices, by preventing or discouraging unintended RF energy release and accidental injury to the patient or surgeon. The invention includes modification of a known device to insulate, isolate or shield the distal end of a metal heat sink on such device (for example, by adding electrical insulation over the distal end), thereby preventing or discouraging the unwanted release of energy.
The above summary is not intended to describe each illustrated embodiment or every implementation of the disclosed subject matter. The details of one or more embodiments of the invention are set forth in the accompanying Drawing and this Specification. Other features, objects, and advantages of the invention will be apparent from the Drawing, the Specification and the claims.
The disclosed subject matter may be more completely understood from the accompanying figures, in which:
Like reference symbols in the various figures of the Drawing indicate like elements.
The elements in the Drawing are not to scale.
DefinitionsUnless the context indicates otherwise, the following terms shall have the following meaning and shall be applicable both to the singular and plural:
The terms “conductor”, “conductive” and “conducting” mean electrically conductive, and refer to materials that readily permit the flow of electrical current through such material. Conductive materials may in some instances be thermally conductive but are not always so. Materials such as carbon black, moisture and metals are representative conducting materials.
The term “electrosurgical device” means an electrical device designed for handheld use by a surgeon to dispense RF or other energy through the tip of an electrode into target surgical tissue, in order to cut or coagulate the tissue during a surgical procedure.
The terms “insulator”, “insulation” and “insulating” mean electrically insulating, and refer to dielectric materials that permit little, if any, flow of electrical current through such material. Insulating materials may in some instances be thermal insulators but are not always so. Materials such as glass, metal oxides, porcelain, paper, plastics, polymers and rubbers are representative insulating materials.
The terms “radiofrequency energy” or “RF” energy mean energy from the electromagnetic spectrum having a frequency between about 3 kilohertz (3 kHz) and about 300 gigahertz (300 GHz).
DETAILED DESCRIPTIONSurgical devices should not unduly impede the surgeon's view of the operating field. This is particularly troublesome in electrosurgical devices, especially those with extra features beyond energy delivery, such as added illumination, smoke evacuation, saline delivery, or other ancillary features.
In the case of an electrosurgical device which also provides added illumination (viz. light directed at the surgical field), the light desirably is emitted near the distal end of the device, where any added bulk may also directly impede the surgeon's view. Device designers have consequently sought to minimize the distal profile of such devices, and to make the associated components as small, thin and few in number as possible.
In an additional embodiment, not shown in the Drawing, a continuous or discontinuous (e.g., screened) conductive layer may be placed between cladding 928 and heat shield 104, and connected to an earth ground. Doing so can reduce the voltage potential at cut end 134 and along the length of heat shield 104, and discourage unintended external current flow or plasma generation. The additional conductive layer may if desired be included as a part of cladding 928 (for example, as an outer layer) or may be included as a part of heat sink 104 (for example, as an inner layer separated from the inner metallic wall of heat sink 104 by a suitable insulating layer on such inner wall. When such an additional conductive layer is employed, it may also be necessary or desirable to employ additional insulating measures on portions of the device inside the additional conductive layer (for example, by making changes to cladding 928 as discussed in connection with
In an additional embodiment, not shown in the Drawing, electrode 106 and one or more of optical waveguide 116, light source 120, light collector 124 and light emitting element 126 can be redesigned so that those portions of electrode 106 that lie inside heat sink 104 are further from the inner wall of heat 110 than is presently the case in device 100. In one embodiment, electrode 106 may be made narrower as it passes through light emitting element 126 and optical waveguide 116. In the same or another embodiment, leg 110 is rerouted so that it runs through the center of device 100 rather than near the inner wall of heat sink 104, and light source 120 and light collector 124 are modified so that LED 122 is not in the way of leg 110 and optical waveguide 116 is edge-lit rather than centrally illuminated.
In an additional embodiment, not shown in the Drawing, all or at least a distal portion of heat sink 104 is made from an insulating material rather than from metal. Exemplary such materials include ceramics, glass and plastics. The thickness, composition and configuration of such an insulating material may be empirically determined using the Example 1 or Example 2 procedures discussed above in connection with the
The various insulation materials mentioned above may be interchanged for one another or replaced or combined with a variety of other insulation materials. Preferred insulation materials include acrylics, acrylates, acrylonitrile-butadiene-styrene (ABS) copolymers, cyanoacrylate adhesives, epoxies, fluorinated ethylene propylene (FEP) elastomers, polycarbonates, polyimides, polytetrafluoroethylene (PTFE) plastics, natural and synthetic rubbers, non-conductive adhesives, RTV and other silicone rubbers, polyurethanes, inorganic dielectrics, glass, ceramics, porcelain, and other insulating materials that will be familiar to persons having ordinary skill in the art.
EXAMPLES Example 1 Simulated ElectrosurgerySimulated electrosurgery was performed using a skinless chicken breast, a Valleylab Force FX™ isolated output electrosurgical generator set to 50 watt, high coagulation output, and device 100. The device had previously been used in an electrosurgical procedure. The results are shown in
These results suggest that in tight anatomical spaces where contact between the edge of the metal heat sink tube and tissue cannot be avoided, tissue damage will likely occur due to RF energy release between the distal edge of the metal tube and the surgical target tissue, particularly when the device is used for coagulation.
Example 2 IEC Hi-Pot TestInternational Standard IEC 60601-2-2 (the IEC Hi-Pot Test) may be used to test dielectric strength and leakage current for both monopolar and bipolar high frequency electrosurgical devices, and their individual components. An Invuity PhotonBlade electrosurgical device that had previously been used in a surgical procedure was disassembled and its components subjected to the IEC Hi-Pot Test to determine breakdown voltages and evaluate potential energy leakage for various components and subassemblies. The Valleylab Force FX™ electrosurgical generator used in Example 1 was employed for the IEC test. The Force FX generator has a maximum voltage output of 3.89 KV RMS. Each of the handle 102 only (without the heat sink 110 and the components it contains); the handle 102 with the heat sink 110 and the components it contains (but without buttons); the handle 102 and its cable (but without buttons and without heat sink 110 and the components it contains); and the heat sink 110 and some of components it contains (but without handle 102 and the exposed portion of electrode 106) were evaluated for potential energy leakage. The test results are shown below in Table 1.
The results in Table 1 show that each of the tested components may have voltage breakdown issues, with the heat sink representing the weakest tested link.
Various embodiments of systems, devices, and methods have been described herein. These embodiments are given only by way of example and are not intended to limit the scope of the claimed invention. It should be appreciated, moreover, that the various features of the embodiments that have been described may be combined in various ways to produce numerous additional embodiments. Moreover, while various materials, dimensions, shapes, configurations and locations, etc. have been described for use with disclosed embodiments, others besides those disclosed may be utilized without exceeding the scope of the claimed inventions. For example, persons of ordinary skill in the relevant art will recognize that the subject matter hereof may comprise fewer features than illustrated in any individual embodiment described above. The embodiments described herein are not meant to be an exhaustive presentation of the ways in which the various features of the subject matter hereof may be combined. Accordingly, the embodiments are not mutually exclusive combinations of features; rather, the various embodiments can comprise a combination of different individual features selected from different individual embodiments, as understood by persons of ordinary skill in the art. Moreover, elements described with respect to one embodiment can be implemented in other embodiments even when not described in such embodiments unless otherwise noted.
Although a dependent claim may refer in the claims to a specific combination with one or more other claims, other embodiments can also include a combination of the dependent claim with the subject matter of each other dependent claim or a combination of one or more features with other dependent or independent claims. Such combinations are proposed herein unless it is stated that a specific combination is not intended.
For purposes of interpreting the claims, it is expressly intended that the provisions of 35 U.S.C. § 112(f) are not to be invoked unless the specific terms “means for” or “step for” are recited in a claim.
Claims
1. An electrosurgical device comprising:
- a) a handle;
- b) a conductive electrode supported by the handle and having a tip for cutting or cauterizing tissue;
- c) an illumination element coupled to the handle, the illumination element comprising a light source, an optical waveguide, and a light emitting element illuminating the electrode tip;
- d) a metallic tubular heat sink surrounding at least part of the conductive electrode and illumination element and having a distal outer edge that abuts against the light emitting element; and
- e) an insulating, shielding or other isolating element that prevents or discourages unintended current flow or plasma formation between the distal outer edge and nearby patient tissue.
2-29. (canceled)
30. An electrosurgical device comprising:
- a) a handle;
- b) a conductive electrode supported by the handle and having a tip for tissue cutting or tissue cauterizing;
- c) an illumination element having a light source, an optical waveguide, and a light emitting element illuminating the electrode tip;
- d) a metallic tubular heat sink that can be slidably extended from the handle, the heat sink: surrounding at least part of the conductive electrode and at least part of the illumination element, having a length, having a distal outer edge that abuts the light emitting element, and having a breakdown voltage between the distal outer edge and nearby patient tissue when the device is used to dispense radiofrequency energy through the electrode tip; and
- e) a plastic insulating sleeve or plastic insulating collar that is placed over at least a portion of the illumination element and over the distal outer edge of the heat sink, and that increases the heat sink breakdown voltage.
31. The device of claim 30, wherein the plastic insulating sleeve or plastic insulating collar surrounds the distal outer edge.
32. The device of claim 30, wherein the plastic insulating sleeve or plastic insulating collar is a cured or hardened bead of insulating material.
33. The device of claim 30, wherein there is a bead of insulating material between the light emitting element and the distal outer edge that abuts the light emitting element.
34. The device of claim 30, wherein the heat sink has an inner sidewall and an outer sidewall, and the plastic insulating sleeve or collar covers at least a portion of the outer sidewall.
35. The device of claim 34, further comprising an insulating element that covers at least a portion of the inner sidewall and increases the heat sink breakdown voltage.
36. The device of claim 30, wherein the plastic insulating sleeve or plastic insulating collar is a plastic insulating collar.
37. The device of claim 36, wherein the collar is tubular and has a thickness of at least 0.1 mm and a width of at least 2 mm.
38. The device of claim 36, wherein the collar is opaque, the light emitting element has an outer edge, and light is not emitted from the outer edge of the light emitting element during use of the device.
39. The device of claim 36, wherein the collar is a material selected from the group consisting of acrylics, acrylates, epoxies, fluorinated ethylene propylene (FEP) elastomers, polycarbonates, polyimides, polytetrafluoroethylene (PTFE) and polyurethanes.
40. The device of claim 36, wherein the collar is acrylonitrile-butadiene-styrene (ABS) copolymer.
41. The device of claim 30, wherein the plastic insulating sleeve or plastic insulating collar is a plastic insulating sleeve.
42. The device of claim 41, wherein the plastic insulating sleeve is a tubular hardened layer of organic material extending along at least the distal 20 mm of the heat sink.
43. The device of claim 42, wherein the plastic insulating sleeve extends along the entire length of the heat sink.
44. The device of claim 42, wherein the sleeve is heat-shrink tubing.
45. The device of claim 42, wherein the sleeve is polyolefin.
46. The device of claim 42, wherein the sleeve is polyvinyl chloride.
47. The device of claim 30, wherein the device includes:
- a tubular plastic insulating sleeve extending along at least the distal 20 mm of the heat sink, and
- a tubular plastic insulating collar having a thickness of at least 0.1 mm and a width of at least 2 mm.
48. The device of claim 30, wherein the electrode includes a conductive leg portion that resides in a slot in the optical waveguide and extends towards the handle, and the conductive leg portion is connected to a conductive cable that passes through the handle and supplies radiofrequency energy to the electrode.
49. The device of claim 48, wherein the device further comprises a layer of plastic cladding that surrounds the optical waveguide and increases the heat sink breakdown voltage.
50. The device of claim 49, wherein the cladding has a thickness of at least 0.1 mm.
51. The device of claim 48, wherein at least some of the conductive leg portion is coated with a layer of an insulating material that increases the heat sink breakdown voltage.
52. The device of claim 51, wherein the insulating material is heat-shrink plastic tubing.
53. The device of claim 30, wherein the heat sink breakdown voltage is increased such that when performing simulated electrosurgery using chicken tissue and an operating power of 10 watts and while laying the heat sink atop such chicken tissue, the heat sink does not char the chicken tissue.
54. The device of claim 30, wherein the plastic insulating sleeve or plastic insulating collar increases the heat sink breakdown voltage, measured without the handle and tip, to at least 2 KV RMS @ 20 seconds.
55. An electrosurgical device comprising:
- a) a handle;
- b) a conductive electrode supported by the handle and having a tip for tissue cutting or tissue cauterizing;
- c) an illumination element having a light source, an optical waveguide, and a light emitting element illuminating the electrode tip;
- d) a metallic tubular heat sink that can be slidably extended from the handle, the heat sink: surrounding at least part of the conductive electrode and at least part of the illumination element, having a length, having a distal outer edge that abuts the light emitting element, and having a breakdown voltage between the distal outer edge and nearby patient tissue when the device is used to dispense radiofrequency energy through the electrode tip;
- e) a tubular plastic insulating sleeve placed over at least a portion of the illumination element and over the distal outer edge of the heat sink, wherein the plastic insulating sleeve extends along at least the distal 20 mm of the heat sink length and increases the heat sink breakdown voltage;
- f) a tubular plastic insulating collar placed over at least a portion of the illumination element and over the distal outer edge of the heat sink, wherein the plastic insulating collar has a thickness of at least 0.1 mm, a width of at least 2 mm and increases the heat sink breakdown voltage;
- g) a layer of plastic cladding that surrounds the optical waveguide, has a thickness of at least 0.1 mm and increases the heat sink breakdown voltage;
- wherein the electrode includes a conductive leg portion that resides in a slot in the optical waveguide and extends towards the handle, the conductive leg portion is connected to a conductive cable that passes through the handle and supplies radiofrequency energy to the electrode, and at least some of the conductive leg portion is coated with a layer of heat-shrink plastic tubing that increases the heat sink breakdown voltage.
56. The device of claim 55, wherein the heat sink breakdown voltage is increased such that when performing simulated electrosurgery using chicken tissue and an operating power of 10 watts and while laying the heat sink atop such chicken tissue, the heat sink does not char the chicken tissue.
57. The device of claim 55, wherein in combination the tubular plastic insulating sleeve, tubular plastic insulating collar, layer of plastic cladding and layer of heat-shrink plastic tubing increase the heat sink breakdown voltage, measured without the handle and tip, to at least 2 KV RMS @ 20 seconds.
58. An electrosurgical device comprising an electrical device designed for handheld use by a surgeon to dispense radiofrequency energy from the electromagnetic spectrum having a frequency between about 3 kilohertz (3 kHz) and about 300 gigahertz (300 GHz) through the tip of an electrode into target surgical tissue, in order to cut, coagulate or cauterize such surgical tissue during a surgical procedure, the electrosurgical device comprising: wherein:
- a) a handle that can be held by the surgeon;
- b) an electrically conductive electrode supported by the handle and having a tip for cutting, coagulating or cauterizing such surgical tissue during such surgical procedure, the electrically conductive electrode being a material that readily permits the flow of electrical current through such conductive electrode material;
- c) an illumination element having: a light source including a light emitting diode, a parabolic light collector and optical waveguide that capture light emitted from the light emitting diode and conduct such light towards the electrically conductive electrode tip, and a light emitting element including a front face having lenslets that illuminate the electrode tip and direct such light onto such target surgical tissue to be cut, coagulated or cauterized during such surgical procedure;
- d) a metallic tubular heat sink that can be slidably extended from the handle, the heat sink: surrounding at least part of the conductive electrode and at least part of the illumination element, having a length, having a distal outer edge that abuts the light emitting element, and having a breakdown voltage between the distal outer edge and nearby patient tissue when the device is used to dispense radiofrequency energy through the electrode tip;
- e) a collet or other locking mechanism on the handle that permits the surgeon to vary the length of the metallic tubular heat sink and electrosurgical device as may be needed for particular surgical procedures;
- f) a tubular plastic insulating sleeve placed over at least a portion of the illumination element and over the distal outer edge of the metallic tubular heat sink, the plastic insulating sleeve being a hardened layer of organic material that extends along at least the distal 20 mm of the metallic tubular heat sink length and increases the heat sink breakdown voltage while permitting little, if any, flow of electrical current through such hardened layer of organic material while cutting, coagulating or cauterizing such surgical tissue during such surgical procedure;
- g) a tubular plastic insulating collar placed over at least a portion of the illumination element and over the distal outer edge of the metallic tubular heat sink, the plastic insulating collar having a thickness of at least 0.1 mm, a width of at least 2 mm and increasing the heat sink breakdown voltage while permitting little, if any, flow of electrical current through such plastic insulating collar while cutting, coagulating or cauterizing such surgical tissue during such surgical procedure;
- the electrically conductive electrode includes a conductive leg portion that readily permits the flow of electrical current through such conductive leg portion while cutting, coagulating or cauterizing such surgical tissue during such surgical procedure;
- the conductive leg portion resides in a slot in the optical waveguide;
- the electrically conductive electrode is connected to a conductive cable that readily permits the flow of electrical current through such conductive cable while cutting, coagulating or cauterizing such surgical tissue during such surgical procedure;
- the conductive cable passes through the handle and supplies radiofrequency energy to the electrically conductive electrode while cutting, coagulating or cauterizing such surgical tissue during such surgical procedure;
- some or all of the conductive leg portion of the electrically conductive electrode is coated with a layer of an insulating material in the form of plastic heat-shrink tubing that increases the heat sink breakdown voltage while permitting little, if any, flow of electrical current through such layer of insulating material in the form of plastic heat-shrink tubing while cutting, coagulating or cauterizing such surgical tissue during such surgical procedure; and
- a layer of plastic cladding surrounds the optical waveguide, the layer of plastic cladding having a thickness of at least 0.1 mm and increasing the heat sink breakdown voltage while permitting little, if any, flow of electrical current through such layer of plastic cladding while cutting, coagulating or cauterizing such surgical tissue during such surgical procedure.
Type: Application
Filed: Feb 2, 2018
Publication Date: Jan 17, 2019
Inventor: David Hubelbank (Portsmouth, NH)
Application Number: 15/887,503