Electrosurgical electrode

Abstract

The present invention addresses the problem of providing an electrosurgical electrode that can keep a portion that could be an operation part from overheating.　An electrosurgical electrode for performing surgery on biological tissue, the electrosurgical electrode comprising a principal body that can emit high-frequency energy. The surface of the principal body has: a coated part (A) that is coated with a resin coating that is at least 10 μm thick; and a region (B) that is coated with an oxide film and / or a resin coating that is no more than 1.0 μm thick or is uncoated. Region (B) is an active surface that can distribute high-frequency energy to biological tissue from the principal body. The ratio (β1 / α1) of the area (β1) of region (B) to the area (α1) of the coated part (A) is 0.01–0.5.

Description

Technical Field

[0001] The present invention relates to an electrosurgical electrode of an electrosurgical instrument used as a medical device and used in surgery of living tissues.

Background Art

[0002] In surgery, an electrosurgical instrument (so-called electrosurgical knife) that can stop bleeding (coagulate) or incise by dispersing a high-frequency current generated from the main body from the electrosurgical electrode to the living tissue is essential. As a problem caused by the use of an electrosurgical knife, there is a problem of "scab" in which carbides such as living tissues adhere to the tip of the electrosurgical knife. Regarding this problem, a method for mass-producing a plurality of electrodes each of which can be connected to a suitable power source for surgery, including a step of preparing a conductive stock material, the stock material having a shape and dimensions capable of forming a plurality of electrode blanks, and further including a step of coating at least a part of the stock material with a non-adhesive layer and a step of forming a plurality of coated electrode blanks, has been proposed (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, since the electrosurgical electrode described in Patent Document 1 has a non-adhesive layer, heat is hardly released from the surface of the electrosurgical electrode, and the temperature of the tip portion of the electrosurgical electrode, that is, the operating region closest to the biological tissue for incising and / or hemostatic the biological tissue, may rise too much. When the temperature of the tip portion of the electrosurgical electrode rises too much, excessive heat is transmitted from the operating region to the affected part, resulting in excessive heat invasion and damage to healthy tissues. The present invention solves such problems, and an object thereof is to provide an electrosurgical electrode capable of suppressing excessive rise in the temperature of the operating region.

Means for Solving the Problems

[0005] The inventors of the present invention have repeatedly studied to solve the above problems, and an electrosurgical electrode having a main body capable of emitting high-frequency energy and used for surgery of biological tissues, wherein the surface of the main body has a coated portion (A) coated with a resin coating having a thickness of 10 μm or more, and a region (B) covered with or not coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less, and the region (B) is an effective surface capable of dispersing high-frequency energy from the main body to the biological tissue, and the ratio (β1 / α1) of the area (β1) of the region (B) to the area (α1) of the coated portion (A) is within a range of 0.01 or more and 0.5 or less. It has been found that the problem can be solved by the electrosurgical electrode. Also, as another method, an electrosurgical electrode having a main body capable of emitting high-frequency energy, which is used in the surgery of biological tissue, wherein the surface of the main body has a coated portion (A) coated with a resin coating having a thickness of 10 μm or more, and a region (B) coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less or not coated, and the region (B) includes an operating region that is closest to the biological tissue in the main body and incises and / or stops bleeding of the biological tissue, and the region (B) includes a surface in contact with all or part of the operating region, and the surface includes a region surrounded by a line in contact with the operating region and a line translated perpendicularly along the surface from the line by at least 2.0 mm. It has been found that the problem can be solved by the electrosurgical electrode.

[0006] That is, the present invention may include the following. (1) An electrosurgical electrode having a main body capable of emitting high-frequency energy, which is used in the surgery of biological tissue, wherein the surface of the main body has a coated portion (A) coated with a resin coating having a thickness of 10 μm or more, and a region (B) coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less or not coated, the region (B) is an effective surface capable of dispersing high-frequency energy from the main body to the biological tissue, and the ratio (β1 / α1) of the area (β1) of the region (B) to the area (α1) of the coated portion (A) is in the range of 0.01 or more and 0.5 or less. (2) An electrosurgical electrode having a main body capable of emitting high-frequency energy, which is used in the surgery of biological tissue, wherein the surface of the main body has a coated portion (A) coated with a resin coating having a thickness of 10 μm or more, and a region (B) coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less or not coated, the region (B) includes an operating region that is closest to the biological tissue in the main body and incises and / or stops bleeding of the biological tissue, The region (B) includes a surface that contacts all or part of the operation region, and the surface includes a region surrounded by a line that contacts the operation region and a line that is translated at least 2.0 mm perpendicularly along the surface from the line, for an electrosurgical electrode. (3) The region (B) includes an operation region that is closest to the living tissue in the main body and incises and / or stops bleeding of the living tissue. The region (B) includes a surface that contacts all or part of the operation region, and the surface includes a region surrounded by a line that contacts the operation region and a line that is translated at least 2.0 mm perpendicularly along the surface from the line, for the electrosurgical electrode according to (1) above. (4) The main body has a front surface that is a main surface, a back surface that faces the front surface, and side surfaces that are sandwiched between the front surface and the back surface, and the region (B) is included in the side surfaces, for the electrosurgical electrode according to any one of (1) to (3) above. (5) The main body has an annular structure, for the electrosurgical electrode according to any one of (1) to (3) above. (6) The main body has a rod-shaped structure, and a needle structure is included at the extended tip of the rod-shaped structure, for the electrosurgical electrode according to any one of (1) to (3) above. (7) The main body has a spherical structure, for the electrosurgical electrode according to any one of (1) to (3) above. [Advantages of the Invention]

[0007] According to the present invention, an electrosurgical electrode capable of suppressing excessive temperature rise in a portion that can be an operation region can be provided. [Brief Description of the Drawings]

[0008]

Figure 1

Figure 2

[0009] Embodiments of the present invention are electrosurgical electrodes having a main body capable of emitting high-frequency energy, which are used in surgeries on biological tissues. The surface of the main body has a coated portion (A) coated with a resin coating having a thickness of 10 μm or more, and a region (B) coated or not coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less. The region (B) is an effective surface capable of dispersing high-frequency energy from the main body to the biological tissue.

[0010] <Electrosurgical Electrode> An electrosurgical electrode is an electrode that is detachably attached to the tip of an electrosurgical instrument such as a so-called electric scalpel. By emitting high-frequency waves from the main body of the electrode to the biological tissue, hemostasis (coagulation) or incision of the biological tissue can be performed. An electrosurgical electrode is composed of a conductive material. More specifically, examples include iron-based metal materials, zinc-plated metal materials, aluminum-based metal materials, magnesium-based metal materials, nickel-based metal materials, titanium-based metal materials, zirconium-based metal materials, copper-based metal materials, tin-based metal materials, tungsten-based metal materials, chromium-based metal materials, manganese-based metal materials, molybdenum-based metal materials, cobalt-based metal materials, etc., but stainless steel is more preferable. Examples of electrosurgical instruments to which the electrosurgical electrode is attached typically include electrosurgical scalpels such as monopolar scalpels and bipolar scalpels, and laparoscopes. Examples of monopolar scalpels include those having shapes such as blade type, annular structure type, rod-like structure type having a needle structure at the tip, and spherical structure type. A schematic diagram of an example of an electrosurgical electrode is shown in FIG. 1.

[0011] FIG. 1 is a schematic diagram showing an example of a blade-type electrosurgical electrode whose tip portion is plate-shaped. The electrosurgical electrode 10 is a member detachable from an electrosurgical instrument body (not shown). The electrosurgical electrode 10 is composed of an electrical connection portion 13 electrically connected to the electrosurgical instrument body, a main body 11 that emits high-frequency waves in proximity to the biological tissue, and an intermediate portion 12 that connects the electrical connection portion 13 and the main body 11.

[0012] Fig. 2 is an enlarged view of the main body 11 in Fig. 1. In this embodiment, the surface of the main body 11 includes a coated portion (A) 111 (hatched area in the figure) that is covered with a resin coating having a thickness of 10 µm or more, and a region (B) 112 (dotted area in the figure) that is either uncoated or covered with an oxide film and / or a resin coating having a thickness of 1.0 µm or less.

[0013] The main body 11 has a generally rectangular shape and includes a front surface, which is the main surface, a back surface opposite the front surface, and a tip portion (tip surface) and side portions (both side surfaces) sandwiched between the front surface and the back surface. The tip portion and side portions include a region (B) that is either uncoated or coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less. While region (B) is preferably present at the tip portion and side surfaces, it is not limited to the tip portion and side surfaces and may be present at a portion of the front surface and / or back surface. Specifically, region (B) may include tip portion 112a and a region 112b of the side surfaces that is continuous with the tip portion. While region 112b is considered to be part of the side surfaces in this embodiment, it may also be the entire side surfaces. Furthermore, the tip 112a is closest to the living tissue and can be the operating area for incising the living tissue and stopping bleeding. While the blade-type electrosurgical electrode shown in Fig. 2 has a rectangular main body, the electrode is not limited to this and may have any shape as long as it has a front surface, a back surface, a tip portion, and side portions. The front and back surfaces may have the same size (area) or different sizes. In this specification, the "main surface" refers to the plane with the largest area.

[0014] In this embodiment, the ratio (β1 / α1) of the area (β1) of the region (B) 112 to the area (α1) of the coating portion (A) 111 is within the range of 0.01 to 0.5. By setting the value of (β1 / α1) within the above range on the surface of the main body 11, an electrosurgical electrode can be obtained that can prevent excessive temperature rise in the area that can become the active area. The range of (β1 / α1) is preferably 0.027 or more and preferably 0.476 or less.

[0015] The coating portion (A) 111 may be coated with a resin coating having a thickness of 10 μm or more. Examples of resin coatings include fluorine-containing resins such as Teflon (registered trademark) and PTFE, and silicone resins, and preferably have an anti-adhesion function (anti-fouling function). The resin coating may be a single layer or a laminate of multiple layers. If it is a laminate of multiple layers, the multiple layers may be made of the same resin or different resins. In addition, an oxide film may be formed between the resin coating and the main body. The resin coating can be formed by bringing a resin composition containing a fluorine-containing resin or a silicone resin into contact with the main body 11. The resin composition may contain additives such as a filler, a plasticizer, a release agent, and a crosslinking agent. The thickness of the resin coating may be 20 μm or more, or may be 30 μm or more. There is no particular upper limit, but it may be 1 mm or less.

[0016] The region (B) may or may not be coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less, and is an effective surface for dispersing high-frequency energy from the main body to biological tissue. Therefore, when an electrosurgical instrument equipped with an electrosurgical electrode is used, the region (B) is closest to the biological tissue and includes the active region for incising the biological tissue and / or for stasis of bleeding. The oxide film and / or resin coating that region (B) may have is extremely thin compared to resin coating (A), and its thickness is 1.0 μm or less, but may be 0.9 μm or less, 0.8 μm or less, 0.7 μm or less, 0.6 μm or less, 0.5 μm or less, 0.4 μm or less, 0.3 μm or less, 0.2 μm or less, 0.1 μm or less, or 0.05 μm or less.

[0017] In another embodiment, the region (B) includes a surface that contacts all or a part of the operation region in the main body where the biological tissue is incised and / or hemostatic closest to the biological tissue. The surface may include a region surrounded by a line that contacts the operation region and a line that is translated at least 2.0 mm perpendicularly along the surface from the line. By having the region (B) within such a range, it is possible to prevent the temperature of the operation region from rising excessively due to heat being trapped around the operation region where the biological tissue is incised and / or hemostatic. Preferably, the region (B) may include a region surrounded by a line that is translated at least 3.0 mm perpendicularly along the surface from the line. As described above, the region (B) may include the tip portion 112a, may include a part of the side surface portion 112b, and may include a part of the front surface and / or the back surface. However, it is preferable that the region (B) includes the tip portion 112a, more preferably includes a part of the side surface portion 112b, and even more preferably includes a part of the front surface and / or the back surface. That is, the priority order of the portions that can be the region (B) is the tip portion 112a, a part of the side surface portion 112b, the front surface and the back surface, in that order. Also, in the side surface portion, the front surface, and the back surface, it is preferable that a part of the region (B) exists from the tip portion side. Also, the region surrounded by a line that contacts the operation region and a line that is translated at least 2.0 mm perpendicularly along the surface including the operation region from the line may or may not be coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less.

[0018] The main body of the electrosurgical electrode according to an embodiment of the present invention can be manufactured, for example, by the following method. In one example, after performing degreasing treatment, substrate treatment, etc. on the main body as necessary, the main body is immersed in a resin coating composition to perform resin coating on the entire surface of the main body. Then, it can be manufactured by cutting the tip portion and the side surface portion of the main body, and, if necessary, desired portions of the front surface and the back surface. The degreasing treatment, substrate treatment, etc. are not particularly limited as long as they can form an oxide film and / or a resin coating, and known methods can be used. Also, the resin coating composition is not particularly limited as long as it is a resin composition containing a fluororesin or a silicone resin.

[0019] <Shape of the main body> The shape of the main body 11 is not particularly limited, and in addition to the blade shape of the main body 11 shown in FIG. 2, it may be an annular type (loop type) shape, a ball type shape, or a needle type shape. These are electrosurgical electrodes used as the cutting electrode of an electrosurgical knife. In addition to these, it may be an electrosurgical electrode attached to a laparoscope, such as a wire L-shaped hook type, a straight spatula type, a wire J-shaped hook type, a syringe type, etc. The main bodies exemplified so far are monopolar type electrosurgical electrodes, but they may be bipolar type electrosurgical electrodes.

[0020] <Electrical connection part> The electrical connection part 13 is a part in the electrosurgical electrode 10 that is electrically connected to the electrosurgical instrument main body. The electrical connection part 13 is detachable from the electrosurgical instrument main body, and usually, the electrical connection part 13 and the electrosurgical instrument main body are configured to be able to be fitted by a fitting structure or the like. Note that the electrical connection part is also made of a conductive material, and the constituent material may be the same as or different from that of the main body 11.

[0021] <Intermediate part> The intermediate part 12 is a member that connects the main body 11 and the electrical connection part 13. It is necessary to be made of a conductive material to energize the main body 11, but its shape, length, etc. are not particularly limited. The intermediate portion 12 may have a coating 14. The coating 14 is a cured product of a composition containing an insulating resin. Furthermore, as long as the intermediate portion 12 and the coating 14 are in contact with each other, there are no particular limitations on the size, thickness, shape, etc. of the coating 14. [Example]

[0022] The effects of the present invention will be specifically demonstrated below by way of examples, but the following examples are not intended to limit the scope of the present invention in any way.

[0023] <Manufacturing the main body> A blade-type electrosurgical electrode having a plate-shaped main body 11 was prepared as shown in Figure 1. The materials and blade portion sizes of the prepared electrosurgical electrodes were as follows: Surgical electrode material: Stainless steel SUS304 Blade size: Thickness 0.3 mm, Length 17.0 mm, Width 2.5 mm, Area 0.00009595 m 2 The blade of the electrosurgical electrode was immersed in ethanol (first-grade, manufactured by Junsei Chemical Co., Ltd.) and ultrasonically treated for 10 minutes to remove oil and dirt from the surface. The blade was then dried at 100°C for 10 minutes to remove any adhering ethanol.

[0024] A silicone composition (product name ES-1002T, manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to the blade portion, from which oil and dirt had been removed, using the following dispenser, and then dried at a drying temperature of 150°C for 30 minutes to obtain an electrosurgical electrode with a silicone coating of 70 μm thickness. Dispenser (desktop robot): Musashi Engineering, product name: ML-808GX, SM4000MEGAX-3A-SS

[0025] <Evaluation test> Of the silicone coating covering the main body 11, the coating at the tip (112a in FIG. 2) was shaved off using a cutter knife. The main body 11 in this state was used as Comparative Example 1. Next, regarding the coating on a part of the side surface (112b in FIG. 2), the cutter knife was used to shave it off so that the distance from the tip 112a was the distance shown in Table 1, and Examples 1 to 6 were obtained. Note that the shaving of the coating on the side surface was performed on both opposing surfaces. Next, regarding the coatings on the front and back surfaces of the main body 11 created in Example 6, the cutter knife was used to shave them off so that the distance from the tip was the distance shown in Table 1, and Examples 7 to 10 and Comparative Examples 2 to 3 were obtained. Furthermore, an electrosurgical electrode in which the coating of the main body 11 was not shaved off at all was used as Comparative Example 4.

[0026] For the surgical electrodes of Examples 1 to 10 and Comparative Examples 1 to 4, the maximum temperature and the temperature rise were measured. Specifically, the main body 11 (17 mm from the tip) was inserted into a container filled with porcine blood, and the temperature of the tip of the main body when discharging for 5 seconds at a power output of 75 W was measured with an infrared camera. The maximum temperature of the main body was taken as the maximum temperature during the 5-second measurement of the main body 11. Also, the temperature rise per second was calculated from the measured temperature change to obtain the heating rate per unit time. The evaluation criteria were as follows. The results are shown in Table 1. <Maximum temperature of the main body during 5-second discharge> ◎: 270 °C or less 〇: Over 270 °C and 320 °C or less △: Over 320 °C and 350 °C or less ×: Over 350 °C <Temperature rise per second> ◎: 90 °C / s or less 〇: Over 90 °C / s and 100 °C / s or less △: Over 100 °C / s and 120 °C / s or less ×: Over 120 °C / s

[0027]

Table 1

[0028] Although the present invention will be described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0029] 10 Electrosurgical Electrodes 11 Main body 111 Coating Department 112 areas 112a Tip 112b Part of the side 12 Middle section 13 Electrical Connections 14 Covering

Claims

【Claim 1】 An electrosurgical electrode comprising a main body capable of emitting high-frequency energy and an electrical connection part, which is used for the surgery of biological tissues, wherein the surface of the main body has a coating part (A) coated with a resin coating having a thickness of 10 μm or more, and a region (B) coated or not coated with an oxide film and / or a resin coating having a thickness of 1.0 μm or less, the region (B) being an effective surface capable of dispersing high-frequency energy from the main body to biological tissues, the main body being made of stainless steel, the main body having a substantially rectangular shape and being plate-shaped, with a main surface, a back surface facing the main surface, a tip surface and both side surfaces sandwiched between the main surface and the back surface, one end of the main body being a connection end connected to the electrical connection part, the tip surface being located at the other end opposite to the connection end, the tip surface being the region (B), in both side surfaces, the region (B) exists in a region having a length of 2 mm to 10 mm from the tip surface toward the connection end, an electrosurgical electrode, wherein the ratio (β1 / α1) of the area (β1) of the region (B) to the area (α1) of the coating part (A) is 0.0207447 or more and 0.0756726 or less.

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