Electrosurgical tip

Abstract

The present disclosure relates generally to the field of medical devices. In particular, the present disclosure relates to an electrosurgical tip that includes an electrically conductive and low profile cutting surface to provide high current density radio frequency energy with minimal thermal damage to surrounding tissue. For example, an electrosurgical tip of the present disclosure may include a ring of conductive material that is sputtered about a distal opening of a non-conductive base member, and a strip of conductive material that is sputtered along a longitudinal axis of the non-conductive base member.

Description

This application is a divisional of the Chinese application with the application date of July 29, 2020, application number 202080053867.7, and invention name “Electrosurgical Tip”. Related Applications

[0001] This application claims the benefit of priority under 35 USC §119 to U.S. Provisional Application No. 62 / 880,226, filed on July 30, 2019, entitled “Sputter-Coated Ceramic Electrosurgical Tip,” the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates generally to the field of medical devices. Specifically, the present disclosure relates to an electrosurgical tip that includes an electrically conductive and low-profile cutting surface to provide high current density radiofrequency energy with minimal thermal damage to surrounding tissue. Background of the Invention

[0003] Many endoscopic ultrasound (EUS) guided procedures involve creating a puncture tract (e.g., a fistula) through tissue layers of a target anatomical structure using a tissue penetrating needle, advancing a guide wire through the tissue penetrating needle to position the distal end of the guide wire within the target anatomical structure, and then advancing a medical device having a rounded electrosurgical tip over the guide wire to dilate the puncture tract. To effectively dilate tissue layers with minimal thermal damage (e.g., charring, burning, coagulation, etc.), the electrosurgical tip must deliver radiofrequency energy with sufficient current density through a low surface area profile. Due to these design criteria, conventional electrosurgical tips tend to be expensive and difficult to manufacture.

[0004] With these factors in mind, a variety of beneficial medical outcomes can be achieved through the devices, systems, and methods of the present disclosure. Summary of the invention

[0005] In one aspect, the present disclosure relates to a medical device comprising a non-conductive base component defining a longitudinal axis and a lumen therethrough. An electrically conductive material may be disposed on an outer surface of the non-conductive base component around a distal opening of the lumen. An electrically conductive material may be disposed on an outer surface of the non-conductive base component along the longitudinal axis. The electrically conductive material disposed around the distal opening may include a first layer of electrically conductive material bonded to the non-conductive base component. The electrically conductive material disposed along the longitudinal axis may include a second layer of electrically conductive material bonded to the non-conductive base component. The first and second layers of electrically conductive material may be sputtered onto the non-conductive base component.

[0006] In the described and other embodiments, one or more of the first and second conductive material layers may be sputtered onto the non-conductive base component. A channel may be formed in the outer surface of the non-conductive base component along the longitudinal axis. The second conductive material layer may extend through the channel. The first and second conductive material layers may include titanium. The conductive material disposed about the distal opening may also include a third conductive material layer bonded to the first conductive material layer, and the conductive material disposed along the longitudinal axis may include a fourth conductive material layer bonded to the second conductive material layer. The third and fourth conductive material layers may be sputtered onto the respective first and second conductive material layers. The third and fourth conductive material layers may include niobium. The conductive material disposed about the distal opening may also include a fifth conductive material layer bonded to the third conductive material layer. The conductive material disposed along the longitudinal axis may include a sixth conductive material layer bonded to the fourth conductive material layer. The fifth conductive material layer may include gold. The sixth conductive material layer may include a nickel-copper alloy. The fifth and sixth conductive material layers may be sputtered onto the respective third and fourth conductive material layers. The fifth conductive material layer may be brazed to the third conductive material layer. A sixth conductive material layer may be sputtered onto the fourth conductive material layer. A distal portion of the conductive wire may be welded to the sixth conductive material layer.

[0007] In another aspect, the present disclosure is directed to a system comprising a non-conductive base component attached to a distal end of an electrosurgical sheath. The non-conductive base component may include a conductive material applied around a distal opening of the non-conductive base component and a strip of conductive material applied along a longitudinal axis of the non-conductive base component. An access cannula may be disposed within a lumen of the electrosurgical sheath and may extend through the non-conductive base component.

[0008] In the described and other embodiments, one or more of the conductive material and the strip of conductive material may be applied via sputtering. A channel may be formed in the outer surface of the non-conductive base component along the longitudinal axis. The strip of conductive material may extend through the channel. The channel may be disposed in the distal portion of the electrosurgical sheath. The distal portion of the conductive wire may be disposed in the channel. The distal portion of the conductive wire may be bonded to the channel using solder. The conductive wire may extend along the electrosurgical sheath, and the proximal end of the conductive wire may be connected to the electrosurgical generator. The guide wire may extend through the lumen of the access cannula.

[0009] In yet another aspect, the present disclosure relates to a medical device comprising a non-conductive base component defining a longitudinal axis and a lumen therethrough. A first layer of conductive material may be disposed in a spiral pattern around an outer surface of the non-conductive base component. A second layer of conductive material may be disposed in a spiral pattern around an outer surface of the non-conductive base component. The first and second layers of conductive material may be electrically insulated from each other.

[0010] In the described and other embodiments, the first and second layers of conductive material may be the same. The first and second layers of conductive material may be different. The first and second layers of conductive material may be sputtered onto a non-conductive base component. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Non-limiting embodiments of the present disclosure are described by way of example with reference to the accompanying drawings, which are schematic and not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown is generally represented by a single reference numeral. For purposes of clarity, not every component is labeled in every figure, and not every component of each embodiment is shown where such illustration is not necessary to allow a person skilled in the art to understand the present disclosure. In the drawings:

[0012] Figure 1A A perspective view of an electrosurgical tip is provided in accordance with one embodiment of the present disclosure.

[0013] Figure 1B According to one embodiment of the present disclosure, a cross-sectional view of various conductive material layers is provided.

[0014] Figure 2 A perspective view of an electrosurgical tip is provided in accordance with one embodiment of the present disclosure.

[0015] FIG. 3A to FIG. 3B A perspective view of an electrosurgical tip housed within a fixture for physical vapor deposition is provided according to one embodiment of the present disclosure.

[0016] Figure 4 According to one embodiment of the present disclosure, a fixing device ( FIG. 3A to FIG. 3B ), the fixing device is arranged in a physical vapor deposition chamber.

[0017] FIG. 5A to FIG. 5B A perspective view of an alternative electrosurgical tip configuration is shown in accordance with an embodiment of the present disclosure.

[0018] Figure 6 A perspective view of an electrosurgical system is provided according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0019] The present disclosure is not limited to the specific embodiments described herein. The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope beyond the appended claims. Unless otherwise defined, all technical terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present disclosure belongs.

[0020] Although embodiments of the present disclosure are described with particular reference to electrosurgical tips that include one or more conductive metal layers coated on a non-conductive ceramic base using physical vapor deposition (PVD), electroless plating, electrolytic plating, or brazing, the disclosed devices and methods are not limited to medical devices or electrosurgical devices, but may include a variety of non-conductive devices coated with one or more layers of a variety of conductive materials.

[0021] As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the terms "include" and / or "comprise", or "contain" and / or "have" when used herein specify the presence of stated features, steps, elements and / or components, but do not exclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components and / or groups thereof.

[0022] As used herein, the term "distal" refers to the end farthest from the medical professional when the device is introduced into a patient, and the term "proximal" refers to the end closest to the medical professional when the device is introduced into a patient.

[0023] In various embodiments, the present disclosure as a whole relates to a medical device (e.g., an electrosurgical tip) comprising a single or multiple layers of conductive material precisely applied / deposited in controlled positions and / or patterns on a non-conductive (e.g., ceramic) base and having a low surface area. The conductive material layer can provide high current density radio frequency (RF) energy and minimize or prevent collateral thermal damage to surrounding tissue. Localized components of the conductive material layer of the medical device can be electrically and thermally insulated to prevent injury to the patient and / or prevent thermal damage to the medical device itself.

[0024] refer to Figure 1AIn one embodiment, a medical device 100 of the present disclosure (e.g., an electrosurgical tip) may include a non-conductive base component 110 including a conical or tapered distal portion 118 (e.g., an increasing tapered or inclined surface extending in a constant or varying distal-to-proximal direction) and a cylindrical proximal portion 120 (e.g., having a generally constant outer dimension). The lumen 112 may extend along the longitudinal axis of the non-conductive base component 110. The outer dimension of the cylindrical proximal portion 120 may be less than the maximum outer dimension of the tapered distal portion 118. A groove or channel 116 may be formed in the outer surface of the non-conductive base component 110 (e.g., extending along it) along the longitudinal axis of the proximal portion 120. In addition, the channel 116 may be formed in the proximal end of the distal portion 118 of the non-conductive base component 110 (e.g., extending along it). In various embodiments, the non-conductive base component 110 may include a variety of insulating materials, including but not limited to ceramics, hard plastics, etc. A ring 122 of conductive material (e.g., a circular ring, a trace, etc.) can be disposed on the outer surface of the non-conductive base component 110 around the distal opening 114 of the lumen 112. A strip 124 of conductive material (e.g., a longitudinal strip, a trace, etc.) can be disposed on the outer surface of the distal and proximal portions 118, 120 along the longitudinal axis of the non-conductive base component 110. The distal end of the strip 124 can intersect, overlap, or otherwise contact a portion of the ring 122 to provide a contiguous conductive material layer (e.g., a single / unitary conductive layer) on / along the outer surface of the distal and proximal portions 118, 120 of the non-conductive base component 110. In various embodiments, a portion of the strip 124 of conductive material can be disposed within (e.g., extend through) the channel 116.

[0025] In one embodiment, the ring 122 of conductive material may include a first conductive material layer bonded to the non-conductive base component 110, and the strip 124 of conductive material may include a second conductive material layer bonded to the non-conductive base component 110. The first and second conductive material layers may be the same or different materials. In various embodiments, the first and second conductive material layers may include a metal (e.g., titanium) that provides the advantage of forming / producing strong atomic bonds (e.g., adhesion) with the non-conductive base component 110 (e.g., ceramic). In various embodiments, the first and / or second conductive material layers may be applied or deposited to the non-conductive base component 110 using physical vapor deposition (e.g., sputtering, thermal evaporation, arc spraying, etc.), electroless plating, electrolytic plating, or brazing or other coating applications.

[0026] In one embodiment, the ring 122 of conductive material may include a third conductive material layer that is bonded to the first conductive material layer, and the strip 124 of conductive material may include a fourth conductive material layer that is bonded to the second conductive material layer. The third and fourth conductive material layers may be the same or different materials (e.g., different from each other and / or different from the first and second material layers). In various embodiments, the third and fourth conductive material layers may include a metal (e.g., niobium) that provides the advantage of forming / producing strong atomic bonds (e.g., weldability) with the respective first and second conductive material layers. In various embodiments, the third and fourth conductive material layers may be applied or deposited to the non-conductive base component 110 using physical vapor deposition (e.g., sputtering, thermal evaporation, arc spraying, etc.), electroless plating, electrolytic plating, or brazing or other coating applications.

[0027] In one embodiment, the ring 122 of conductive material may include a fifth conductive material layer that is bonded to the third conductive material layer, and the strip 124 of conductive material may include a sixth conductive material layer that is bonded to the fourth conductive material layer. The fifth and sixth conductive material layers may be the same or different materials (e.g., different from each other and / or different from the first, second, third, and fourth material layers). In various embodiments, the fifth conductive material layer may include a highly conductive metal (e.g., gold) that forms / produces strong atomic bonds with the third conductive material layer. In various embodiments, the sixth conductive material layer may include a conductive metal (e.g., nickel-copper alloy) that forms / produces strong atomic bonds with the fourth conductive material layer and may form strong atomic bonds with a solder layer (discussed below). In various embodiments, the fifth and sixth conductive material layers may be applied or deposited to the non-conductive base component 110 using physical vapor deposition (e.g., sputtering, thermal evaporation, arc spraying, etc.), electroless plating, electrolytic plating, or brazing or other coating applications. In one embodiment, the conductive material layer including the rings 122 (e.g., the first, third, and fifth layers) and the conductive material layer including the strips 124 (e.g., the second, fourth, and sixth layers) may intersect (e.g., overlap, touch, contact, etc.) with each other in a variety of different patterns, layers, and / or configurations to form connected conductive material layers ( Figure 1B Alternatively, the fifth conductive material layer may include a compatible filling material 123 (eg, gold, silver, tin, etc.), and the compatible filling material 123 may be soldered or welded ( Figure 2) to the non-conductive base component (e.g., rather than utilizing physical vapor deposition), and the sixth conductive material layer may be applied or deposited to the non-conductive base component 110 utilizing physical vapor deposition (e.g., sputtering, thermal evaporation, arc spraying, etc.), electroless plating, electrolytic plating, or brazing or other coating applications. In various embodiments, brazing or welding the conductive material layer may provide a cutting surface having a geometry designed for a particular application (e.g., a raised, enlarged or thicker cutting surface, etc.).

[0028] In various embodiments, the ring 122 of conductive material can be a patient contacting portion (e.g., a cutting surface) of the medical device 100, and the strip 124 of conductive material can be a non-patient contacting portion of the medical device. In one embodiment, a distal portion of a conductive wire (not shown) can be disposed within the groove 116 and attached to the sixth conductive material layer by a solder layer formed within the channel 116 on top of the sixth conductive material layer and the conductive wire (disposed therebetween). The proximal end of the conductive wire can be electrically connected to an electrosurgical generator, as discussed below.

[0029] In various embodiments, the inner wall of the lumen 112 may not be coated with a conductive material to thermally and electrically insulate the lumen 112 and any medical device extending therethrough (e.g., a cannula, a guidewire, etc.) from the conductive ring 122 and / or strip 124. In various embodiments, the low profile / low surface area of ​​the conductive ring 122 and strip 124 and the surrounding surfaces of the non-conductive base member 110 (e.g., distal portion 118, proximal portion 120, lumen 112) may conduct sufficient RF energy to effectively cut / penetrate various soft tissue walls (e.g., stomach, duodenum, gallbladder, pancreas, liver, etc.) with minimal collateral thermal damage to the surrounding tissue. The ring 122 may be disposed on the most distal portion of the distal portion 118 so that the tissue contacts the ring 122 first and is subjected to the RF energy for penetrating the tissue.

[0030] In various embodiments, a layer of conductive material may be applied / deposited on the non-conductive base member 110 using a line-of-sight PVD process that utilizes inert plasma atoms to displace metal atoms from a cathode. FIG. 3A to FIG. 3B In one embodiment, the non-conductive base member 110 of the present disclosure may be disposed within a fixture 130 that masks all exterior surfaces of the non-conductive base member 110 except for the surfaces to which the ring 122 and strip 124 will be applied. A plug or blank 132 may be disposed within the distal opening 114 of the non-conductive base member 110 to shield the lumen 112 from contact / coating with atomized metal. Alternatively, the non-conductive base member 110 may be masked by a pre-formed strip, a patternable coating, a photoresist, or other removable coating to define the ring 122 and strip 124.

[0031] refer to Figure 4 In one embodiment, the fixture 130 may be positioned within the sputtering chamber 140 such that one side of the fixture 130 is directly opposite the metal target 148a (e.g., the conductive material to be sputtered). The sputtering chamber 140 may serve as an anode, the metal target 148a may serve as a cathode, and the interior surface of the sputtering chamber 140 may serve as an electrode. An inert gas 146 (e.g., argon) may be pumped into the sputtering chamber 140, energized to a plasma state and an electric field applied to bombard the cathode / metal target 148a. As the plasma atoms contact the metal target 148a, the metal atoms may be displaced from the metal target 148a and directed toward the surface of the fixture 130. A thin layer (e.g., approximately 50 microns) of sputtered metal 148b may then be formed on the surface of the fixture 130, including the unshielded / exposed portion of the non-conductive base member 110 disposed therein. In various embodiments, the fixture 130 can be rotated within the sputtering chamber 140 to expose other unmasked surfaces of the non-conductive base component to the metal target 148a, and the process is repeated. In addition, the metal target 148a can be replaced with a different metal target to apply / deposit various metal layers to corresponding portions of the non-conductive base component 110 (e.g., the ring 122 and the strip 124), as discussed above.

[0032] refer to Figure 6 In one embodiment, the system 200 of the present disclosure may include a non-conductive base component 110 of the medical device 100, which is attached to the distal end of the non-conductive electrosurgical sheath 126. In various embodiments, the proximal portion (not shown) of the non-conductive base component 110 can be received / disposed within the distal portion of the electrosurgical sheath 126, so that the channel 116 (not shown) and the distal portion of the conductive wire (not shown) disposed therein are thermally and electrically insulated. The conductive wire can extend along the electrosurgical sheath 126 (e.g., embedded within the side wall of the electrosurgical sheath) to connect the proximal end of the conductive wire to the electrosurgical generator. The access cannula 129 can extend through the lumen (not shown) of the non-conductive base component 110.

[0033] A variety of advantages can be achieved through the devices, systems, and methods of the present disclosure. For example, the disclosed conductive material layer (applied / deposited on the outer surface of the electrosurgical device using PVD) can allow for a wider range of processing conditions at high temperatures to provide finer surface features (e.g., lower surface area, lower profile, etc.), thereby reducing production costs, simplifying manufacturing, minimizing collateral thermal damage, and maximizing patient safety. The disclosed PVD process can be applied to new medical devices and / or reduce the cost of manufacturing or modifying existing medical devices. For example, the manual and expensive process involved in manufacturing conventional electrosurgical tips, such as where bipolar gold traces are printed in a spiral pattern around a non-conductive tip (Gold Probe of Marlborough, MA) can be used to manufacture electrosurgical tips. TM Boston Scientific (Gold Probe TM Boston Scientific Corp., Marlborough MA.); Figure 5A ) or steel wire wrapped around a ceramic tip (Hot Axios in Marlborough, Massachusetts TM Boston Scientific (HotAxios TM Boston Scientific Corp., Marlborough MA.); Figure 5B )), can be modified to utilize PVD process to apply / deposit bipolar or unipolar conductive layer. In various embodiments, for medical applications where thicker conductive layer may be required, additional conductive material layer can be applied to PVD layer using electroless plating, electrolytic plating and / or brazing.

[0034] In various embodiments, the order in which the various conductive material layers listed above (e.g., titanium, niobium, gold, nickel-copper alloy) may be applied / deposited to the non-conductive base component may be based on their respective bonding properties to the non-conductive base (e.g., ceramic), weldability (e.g., the ability to bond / adhere a highly conductive outer / top layer to an adhesive inner / bottom layer), and / or conductivity (e.g., conductivity of the outer / tissue contacting layer). However, it should be understood that the present disclosure is in no way limited to these materials / metals, the number of layers of such materials, and / or the order or pattern of their deposition. A variety of conductive materials (including, by way of non-limiting example, titanium, niobium, gold, molybdenum, titanium nitride, tantalum, tungsten, platinum, palladium, iridium, tin, nickel, copper, vanadium, silver, zinc or other biocompatible metals, as well as alloys, oxides and nitrides of such materials) may be applied / deposited on the disclosed medical device 100 in a variety of orders / layers, patterns and / or thicknesses.

[0035] In various additional embodiments, the number of layers of conductive material applied to the non-conductive base component (e.g., rings 122 and / or strips 124) is not limited to the first through sixth layers listed above, but may include a single layer, two layers, or any number of additional layers.

[0036] In various additional embodiments, the conductive material layers (e.g., the first, third, and fifth layers) including the rings 122 and the conductive material layers (e.g., the second, fourth, and sixth layers) including the strips 124 may intersect (e.g., overlap, touch, contact, etc.) with each other in a variety of different patterns, layers, and / or configurations to form adjacent conductive material layers. For example, a portion of the second layer may partially overlap a portion of the first conductive material layer, a portion of the third conductive material layer may partially overlap a portion of the second conductive material layer, a portion of the fourth conductive material layer may partially overlap a portion of the third conductive material layer, a portion of the fifth conductive material layer may partially overlap a portion of the fourth conductive material layer, and a portion of the sixth conductive material layer may partially overlap a portion of the fifth conductive material layer.

[0037] In accordance with the present disclosure, all devices and / or methods disclosed and claimed herein can be made and performed without undue experimentation. Although the devices and methods of the present disclosure have been described according to preferred embodiments, it is obvious to those skilled in the art that variations can be applied to the devices and / or methods described herein and the steps or sequence of steps of the methods without departing from the concept, spirit and scope of the present disclosure. All such similar substitutes and modifications obvious to those skilled in the art are deemed to be within the spirit, scope and concept of the present disclosure as defined by the appended claims.

Claims

1. A medical device comprising: a non-conductive base member defining a longitudinal axis and a lumen therethrough; an electrically conductive material disposed on an outer surface of the non-conductive base member around a distal opening of the lumen; and an electrically conductive material disposed on an outer surface of the non-conductive base member along the longitudinal axis; and wherein the conductive material disposed about the distal opening comprises a first layer of conductive material bonded to the non-conductive base component, and wherein the conductive material disposed along the longitudinal axis comprises a second layer of conductive material bonded to the non-conductive base component. 2 . The medical device of claim 1 , wherein one or more of the first and second layers of conductive material are sputtered onto the non-conductive base component.

3. The medical device of any one of claims 1 to 2, further comprising a channel formed in the outer surface of the non-conductive base component along the longitudinal axis, wherein the second layer of conductive material extends through the channel.

4. The medical device of any one of claims 1 to 3, wherein the first and second layers of electrically conductive material comprise titanium.

5. A medical device according to any one of claims 1 to 4, wherein the conductive material arranged around the distal opening also includes a third conductive material layer, which is bonded to the first conductive material layer, and the conductive material arranged along the longitudinal axis includes a fourth conductive material layer, which is bonded to the second conductive material layer, and wherein the third and fourth conductive material layers are sputtered on the corresponding first and second conductive material layers. The medical device of claim 5 , wherein the third and fourth layers of conductive material comprise niobium.

7. A medical device according to any one of claims 5 to 6, wherein the conductive material arranged around the distal opening also includes a fifth conductive material layer, which is bonded to the third conductive material layer, and the conductive material arranged along the longitudinal axis includes a sixth conductive material layer, which is bonded to the fourth conductive material layer.

8. The medical device of claim 7, wherein the fifth conductive material layer comprises gold and the sixth conductive material layer comprises a nickel-copper alloy.

9. The medical device of any one of claims 7 to 8, wherein the fifth conductive material layer is soldered to the third conductive material layer, and the sixth conductive material layer is sputtered on the fourth conductive material layer.

10. The medical device of any one of claims 7 to 9, further comprising a distal portion of an electrically conductive wire, the electrically conductive wire being welded to the sixth layer of electrically conductive material.

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