cautery puncture needle

Abstract

The present invention makes it easy to fine-tune the degree of flexion of a cautery puncture needle. This cautery puncture needle (1) comprises a pipe part and a leading-end electrode (10) which is disposed at the leading end of the pipe part and which is energized with a high-frequency current. The pipe part has a first flexed section and a second flexed section. The first flexed section is positioned on the leading-end side of the pipe part. The second flexed section is positioned on the base-end side of the pipe part. The first and second flexed sections are configured such that the length of the radius of curvature (R1) of the arc of the first flexed section is equal to or greater than the length of the radius of curvature (R2) of the arc of the second flexed section, and the length of the arc of the first flexed section is greater than the length of the arc of the second flexed section. Alternatively, the first and second flexed sections are configured such that the length of the arc of the first flexed section is equal to or greater than the length of the arc of the second flexed section, and the length of the radius of curvature (R1) of the arc of the first flexed section is greater than the length of the radius of curvature (R2) of the arc of the second flexed section.

Description

[Technical Field]

[0001] The present invention relates to a cauterizing puncture needle. [Background technology]

[0002] Conventionally, as in Patent Document 1, a puncture needle including two bent portions has been proposed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-220202 Summary of the Invention [Problem to be solved by the invention]

[0004] However, a user such as a doctor needs to have a high level of skill to adjust the degree of bending of the puncture needle.

[0005] Therefore, one example of an object of the present invention is to facilitate fine adjustment of the degree of bending of the cauterization puncture needle. [Means for solving the problem]

[0006] A cauterization puncture needle according to one aspect of the present invention includes a pipe portion and a tip electrode portion provided at the tip of the pipe portion and through which a high-frequency current is passed. The pipe portion has a first bent portion and a second bent portion. The first bent portion is located on the tip side of the pipe portion. The second bent portion is located on the base end side of the pipe portion. The first bent portion and the second bent portion are configured so that the radius of curvature of the arc of the first bent portion is equal to or longer than the radius of curvature of the arc of the second bent portion and is longer than the arc of the second bent portion. Alternatively, the first bent portion and the second bent portion are configured so that the arc of the first bent portion is equal to or longer than the radius of curvature of the arc of the second bent portion and is longer than the radius of curvature of the arc of the first bent portion. [Effects of the Invention]

[0007] As described above, according to the present invention, it is possible to easily fine-tune the degree of bending of the cauterization puncture needle. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a side view of the cauterization puncture needle and the operation unit of the present embodiment. [Figure 2] FIG. 2 is an enlarged side view of a region including a first region and a second region of the cauterization puncture needle of the present embodiment. [Figure 3] FIG. 2 is a diagram showing a side view and a partial cross section of the tip electrode portion, the first pipe, and the second pipe before bending. [Figure 4] 3 is a diagram showing a side view and a partial cross section of the tip electrode portion and the first pipe. FIG. [Figure 5] FIG. 10 is a diagram showing the cross-sectional structure of the cauterization puncture needle before bending. [Figure 6] FIG. 2 is an enlarged side view of the cauterizing puncture needle of the present embodiment. [Figure 7] FIG. 10 is a diagram showing a side view and a partial cross section of the tip electrode portion, the first pipe, and the second pipe before bending, showing an example of joining that includes both adhesive bonding and spot welding. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present embodiment will be described below with reference to the drawings (see FIGS. 1 to 6). Note that the embodiment is not limited to the following embodiment. Furthermore, the content described in one embodiment is, in principle, also applicable to other embodiments. Furthermore, the embodiments and modifications can be combined as appropriate.

[0010] In Fig. 2, the first pipe 21 and the second pipe 22, which are hidden by the covering portion 40 and cannot be seen from the outside, are shown by dashed lines in order to show the internal structure of the first pipe 21 etc. In Fig. 3, the first pipe 21, which is hidden by the second pipe 22 and cannot be seen from the outside, is shown by dashed lines in order to show the internal structure of the first pipe 21 etc. In Fig. 5, the second region a2 to the seventh region a7 are shortened in the longitudinal direction to show the first region a1 to the seventh region a7.

[0011] (Configuration of cauterization puncture needle 1) As shown in FIG. 1 , the cauterization puncture needle 1 of this embodiment includes a distal electrode portion 10, pipe portions (first pipe 21, second pipe 22), and a covering portion 40. An operating portion 50 such as a luer connector 51 is attached to the base end of the cauterization puncture needle 1. The cauterization puncture needle 1 is used in catheter ablation (myocardial ablation), which applies high-frequency current to an abnormal part inside the body to perform cauterization. In this embodiment, the first pipe 21 and the second pipe 22 are covered by the opaque covering portion 40 and are therefore located in positions that cannot be seen from the outside. However, the covering portion 40 may not be opaque and may be transparent.

[0012] (Tip electrode part 10) As shown in FIG. 2, the tip electrode 10 is provided at the tip side of the first pipe 21. The tip electrode 10 is integrally formed with the first pipe 21 by arc welding such as plasma welding or TIG (Tungsten Insert Gas) welding. The tip electrode 10 is configured to generate Joule heat when a high-frequency current is applied thereto. The shape of the insertion tip of the tip electrode 10 is preferably a semi-elliptical sphere (a bullet shape, or the shape of a rugby ball cut in half in the longitudinal center) with the outer diameter gradually decreasing toward the tip. The shape of the insertion tip of the tip electrode 10 is not limited thereto and may be, for example, a hemisphere. A tubular portion 11 communicating with the first pipe 21 is provided at the base end of the tip electrode 10. A hole 11a is formed in the tubular portion 11. The hole 11a is used as an injection hole for injecting a contrast agent. The hole 11a is formed by laser processing or the like.

[0013] The tip electrode 10 is made of metal to allow high-frequency current to flow through it. It is desirable that the tip electrode 10 be made of a metal that can be photographed with high contrast by X-ray fluoroscopy, such as platinum, iridium, an alloy of platinum and iridium, or an alloy of platinum, iridium, and stainless steel, so that its position in the surgical site can be easily confirmed.

[0014] In this embodiment, the cylindrical portion 11 is described as being formed on the base end side of the distal electrode portion 10, but it may be formed on the distal end side of the first pipe 21.

[0015] (First Pipe 21) As shown in Figures 3 and 4, the first pipe 21 is formed of a hollow cylindrical tube. The first pipe 21 communicates with the tubular portion 11 of the distal electrode unit 10 at its distal end and with the second pipe 22 at its proximal end. That is, the distal electrode unit 10 is provided on the distal side of the first pipe 21. The first pipe 21 extends from a region in contact with the distal electrode unit 10, passing through the inside of the second pipe 22, to a region near the terminal end on the proximal side of the straight region of the second pipe 22 (second region a2 to fifth region a5, which will be described later).

[0016] The outer surface of the tip end of the first pipe 21, which is not inserted into the second pipe 22, is subjected to a matte surface treatment such as blasting. Specifically, the entire area of ​​the outer surface of the first pipe 21 that is covered by the covering portion 40 (described later) is subjected to the matte surface treatment. The first pipe 21 is made of a metal with good flexibility, such as stainless steel such as SUS302, SUS304V, or SUS316L, or various alloys such as Nitinol or CoCr.

[0017] (Second Pipe 22) As shown in Fig. 5, the second pipe 22 is configured as a hollow cylindrical tube. The second pipe 22 has an inner diameter equal to or slightly larger than the outer diameter of the first pipe 21. The second pipe 22 communicates with the first pipe 21 at its distal end and communicates with the operating unit 50 at its proximal end. The second pipe 22 extends from a region close to the distal electrode unit 10 to a region where the operating unit 50 is located (third region a3 to seventh region a7 described below).

[0018] The outer surface of the second pipe 22 is subjected to a matte surface treatment such as blasting. Specifically, a matte surface treatment is applied to the entire area of ​​the outer surface of the second pipe 22 that is covered by the covering portion 40 (described later). The second pipe 22 is made of a metal with good flexibility, for example, stainless steel such as SUS302, SUS304V, or SUS316L, or various alloys such as Nitinol or CoCr.

[0019] The first pipe 21 is inserted into the second pipe 22 from the tip side. The first pipe 21 and the second pipe 22 are joined by laser welding, adhesive, or the like to form a pipe section. The pipe section has a tip side (second region a2) made up of a single layer of the first pipe 21, a base side (sixth region a6 and seventh region a7) made up of a single layer of the second pipe 22, and a section between the tip side and the base side (third region a3 to fifth region a5) made up of two layers of the first pipe 21 and the second pipe 22.

[0020] (Grain size of the grinding stone used in blasting) The grain size of the grindstone used in the blasting process on the first pipe 21 and the second pipe 22 is preferably set to about mesh 80 in JIS grain size (a grain size that passes through a sieve that divides one square inch into 80 parts, but does not pass through a sieve that divides one square inch into 100 parts). However, the grain size of the grindstone used in the blasting process is not limited to this.

[0021] (Covering portion 40) The outer surface on the tip side of the first pipe 21, in a region not inserted into the second pipe 22, and the outer surface of the second pipe 22 are covered by a covering portion 40. The covering portion 40 is used to prevent unintentional high-frequency ablation to blood vessels, organs, etc., and to reduce the sliding resistance of the ablation puncture needle 1 in the living body. The covering portion 40 is composed of a hydrophobic resin material, for example, fluororesins such as PTFE (polytetrafluoroethylene), ETFE (tetrafluoroethylene-ethylene copolymer), PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), etc. The covering portion 40 is composed of a heat-shrinkable tube. After inserting the pipes (the first pipe 21 and the second pipe 22) into the heat-shrinkable tube, it shrinks by heating and adheres to the pipes.

[0022] (Operation unit 50) The operation unit 50 on the proximal end side of the second pipe 22 includes a Luer connector 51, a relay cable 53, and a syringe connection portion 55 (see FIG. 1). The relay cable 53 electrically connects the source of high-frequency (radio wave (RF)) current to the second pipe 22, the first pipe 21, and the tip electrode portion 10. The syringe connection portion 55 is a Luer taper fitting portion to which a syringe is connected. By connecting a syringe filled with a contrast agent to the syringe connection portion 55 and injecting the contrast agent into the first hollow portion 21a and the second hollow portion 22a, the contrast agent is ejected to the outside from the hole 11a formed in the cylindrical portion 11 of the tip electrode portion 10 (see FIG. 5).

[0023] (Outer diameter of each part) The tip electrode portion 10, the first pipe 21, and the covering portion 40 are configured such that the outer diameter d1 of the tip electrode portion 10 is larger than the outer diameter d2 of the first pipe 21 and smaller than the outer diameter d3 of the region of the covering portion 40 covering the first pipe 21 (see FIGS. 2 to 5, for example, d1 = 0.75 mm, d2 = 0.70 mm, d3 = 0.83 mm). That is, it is configured such that the relationship d2 < d1 < d3 holds. The outer diameter d1 of the tip electrode portion 10 here is defined as the outer diameter of the portion with the largest outer diameter among the semi-elliptical spherical or hemispherical proximal end side portion and the cylindrical portion 11.

[0024] (Configuration of the bending portion) The cauterization puncture needle 1 has two bent portions between the distal electrode portion 10 and the base end side of the second pipe 22 (see FIGS. 1 and 6). The two bent portions are formed by bending the corresponding portions (fourth region a4 and sixth region a6) of the pipe portions (first pipe 21 and second pipe 22) formed in a substantially straight line and covered with the covering portion 40.

[0025] The formation of the bent portion is performed after the attachment of the tip electrode portion 10 to the first pipe 21, the attachment of the first pipe 21 to the second pipe 22, the attachment of the covering portion 40 to the first pipe 21 and the second pipe 22, and the attachment of the second pipe 22 to the operating portion 50.

[0026] However, the bent portion may be formed after the first pipe 21 is attached to the second pipe 22 and the covering portion 40 is attached to the first pipe 21 and the second pipe 22, but before at least one of the attachment of the tip electrode portion 10 to the first pipe 21 and the attachment of the second pipe 22 to the operating portion 50 is performed.

[0027] Specifically, the cauterization puncture needle 1 has a first region a1 to a seventh region a7, and bent portions are formed in a fourth region a4 and a sixth region a6. The first region a1 is a region where the distal electrode portion 10 is provided. The second region a2 is a region formed by a single layer of the first pipe 21. The third region a3 is a region formed by two layers of the first pipe 21 and the second pipe 22 and is a straight region (first straight portion) on the distal side. The fourth region a4 is a region formed by two layers of the first pipe 21 and the second pipe 22 and is a bent region (first bent portion). The fifth region a5 is a region formed by two layers of the first pipe 21 and the second pipe 22 and is a straight region (second straight portion) on the proximal side. The sixth region a6 is a region formed by a single layer of the second pipe 22 and is a bent region (second bent portion). The seventh region a7 is a region formed of a single layer of the second pipe 22 and is a linear region (third linear portion). The fifth region a5 is preferably configured with two layers of the first pipe 21 and the second pipe 22, but may be configured with a single layer of the second pipe 22 only.

[0028] The first bent portion is located in a region formed by two layers of the first pipe 21 and the second pipe 22. The second bent portion is located in a region formed by a single layer of the second pipe 22. That is, the pipe portions (first pipe 21 and second pipe 22) are configured so that the region of the pipe portion where the first bent portion is formed is thicker than the region of the pipe portion where the second bent portion is formed. Because the first bent portion is formed in a region formed by two layers of the first pipe 21 and the second pipe 22, the shape of the bent portion is more easily maintained compared to the second bent portion formed in a region formed by a single layer of the second pipe 22. On the other hand, because the second bent portion is formed in a region formed by a single layer of the second pipe 22, it is more easily bent by an external force compared to the first bent portion.

[0029] The two bent portions (the fourth region a4 and the sixth region a6) bend in the same direction. The fourth region a4 and the sixth region a6 are configured so that the radius of curvature R1 of the arc of the fourth region a4 is longer than the radius of curvature R2 of the arc of the sixth region a6, and the arc of the fourth region a4 is longer than the arc of the sixth region a6. Specifically, the fourth region a4 and the sixth region a6 are configured so that the relationships R1 ≥ R2 (e.g., R1 = R2 = 63.6 mm) and the arc length of a4 > the arc length of a6 (e.g., the arc length of a4 = 34.6 mm, the arc length of a6 = 20.6 mm) hold true. Alternatively, the fourth region a4 and the sixth region a6 are configured so that the arc of the fourth region a4 is longer than the arc of the sixth region a6, and the radius of curvature R1 of the arc of the fourth region a4 is longer than the radius of curvature R2 of the arc of the sixth region a6. That is, the arc length of a4 is greater than or equal to the arc length of a6, and R1 is greater than R2. The difference in bending angle between the first bent portion and the second bent portion is preferably within a range of, for example, 5 degrees to 20 degrees.

[0030] The three linear portions (the third region a3, the fifth region a5, and the seventh region a7) extend in a substantially linear manner. Here, "substantially linear" does not only mean extending in a straight line, but also includes a gentle curve with a radius of curvature longer than the radius of curvature R1 of the arc of the fourth region a4 and the radius of curvature R2 of the sixth region a6.

[0031] (Effect of providing two bent sections with different configurations) The fourth region a4 and the sixth region a6 are configured so that the fourth region a4 has a longer arc length and / or a longer radius of curvature than the sixth region a6. Therefore, stress is concentrated in the sixth region a6 on the proximal end side compared to other regions, including the fourth region a4. The sixth region a6 (second bending portion) is easier to bend than other portions, making it easier for users, such as physicians, to fine-tune the degree of bending. Furthermore, the fourth region a4 (first bending portion) is easier to maintain in a bent state, making it less likely to bend accidentally during surgery, etc.

[0032] Furthermore, the fourth region a4 (first bent portion) is composed of two layers, the first pipe 21 and the second pipe 22. The sixth region a6 (second bent portion) is composed of a single layer, the second pipe 22. This makes the sixth region a6 even easier to bend than the fourth region a4, making it easier for users such as doctors to fine-tune the degree of bending. Furthermore, the fourth region a4, which is harder to bend than the sixth region a6, can more easily maintain a bent state. This makes it less likely to bend accidentally during surgery, etc.

[0033] (Effect of Surface Treatment of the Entire Area Covered by the Covering Portion 40 of the Second Pipe 22, etc.) By performing a matte surface treatment on the entire area of ​​the first pipe 21 and the second pipe 22 covered by the covering portion 40, the covering portion 40 adheres tightly to the first pipe 21, etc., and wrinkles are less likely to occur in the covering portion 40. This allows the cauterization puncture needle 1 to be inserted smoothly into the sheath.

[0034] (Effect of increasing the outer diameter d1 of the tip electrode portion 10) By making the outer diameter d1 of the tip electrode unit 10 larger than the outer diameter d2 of the first pipe 21, the electrode surface area of ​​the tip electrode unit 10 can be made larger than in a configuration in which the outer diameter d2 is the same as that of the first pipe 21. Increasing the electrode surface area enables electrically stable cauterization and makes it easier to puncture the intended location. In addition, since the step between the tip electrode unit 10 and the covering unit 40 is small, the covering unit 40 is less likely to peel off or roll up.

[0035] (Effect of providing a straight section between two bends) A fifth region a5 (second straight section) is provided between the fourth region a4 (first bent section) and the sixth region a6 (second bent section). By providing a straight section between the two bent sections, it becomes easier to visually identify the position of the region (fourth region a4) where fine adjustments are required for bending. Furthermore, since the fifth region a5 (second straight section) is composed of two layers, the first pipe 21 and the second pipe 22, it is more difficult to bend than a region composed of a single layer. For this reason, the fifth region a5 is easier to maintain a straight state and is less likely to bend accidentally during surgery, etc.

[0036] (Application example of joining the first pipe 21 and the second pipe 22) The first pipe 21 and the second pipe 22 may be joined by both adhesive and welding. For example, as shown in FIG. 7, the first pipe 21 and the second pipe 21 are joined by adhesive at their distal ends (adhesive region b1, which includes the third region a3 and the fourth region a4) and by spot welding at their proximal ends (fifth region a5). Adhesion is also performed to prevent leakage of contrast medium and other liquids. Spot welding is also performed to ensure electrical continuity up to the distal electrode 10 and to prevent the first pipe 21 and the second pipe 22 from coming loose. Spot welding is performed on a surface including the neutral plane NP of at least one of the first bent portion (fourth region a4) and the second bent portion (sixth region a6). FIG. 7 shows an example in which spot welding is performed on the neutral plane NP at three locations s1, s2, and s3 in the fifth region a5. Adhesion is performed first on the distal end, followed by spot welding on the proximal end.

[0037] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents.

[0038] According to the present specification, the following aspects are provided. (Aspect 1) The cauterization puncture needle includes a pipe portion and a tip electrode portion provided at the tip of the pipe portion and through which high-frequency current is passed. The pipe portion has a first bent portion and a second bent portion. The first bent portion is located on the tip side of the pipe portion. The second bent portion is located on the base end side of the pipe portion. The first bent portion and the second bent portion are configured such that the radius of curvature of the arc of the first bent portion is equal to or greater than the radius of curvature of the arc of the second bent portion and is longer than the arc of the second bent portion. Alternatively, the first bent portion and the second bent portion are configured such that the arc of the first bent portion is equal to or greater than the radius of curvature of the arc of the second bent portion and is longer than the radius of curvature of the arc of the first bent portion.

[0039] According to the first aspect, the first bent portion and the second bent portion are configured so that the first bent portion has a longer arc length and / or a longer radius of curvature than the second bent portion. Therefore, stress is concentrated in the second bent portion on the proximal end side compared to other regions including the first bent portion. The second bent portion is easier to bend than other portions, making it easier for users such as physicians to fine-tune the degree of bending. Furthermore, the first bent portion is easier to maintain in a bent state and less likely to bend accidentally during surgery, etc.

[0040] (Aspect 2) Preferably, the pipe section includes a first pipe and a second pipe. A distal electrode is provided on the distal end side of the first pipe. A proximal end side of the first pipe is inserted into the second pipe. The first bent section is located in a region formed by two layers of the first pipe and the second pipe. The second bent section is located in a region formed by a single layer of the second pipe.

[0041] According to the second aspect, the second bending portion is easier to bend than the first bending portion, making it easier for users such as doctors to fine-tune the degree of bending. Furthermore, the first bending portion, which is harder to bend than the second bending portion, is easier to maintain in a bent state. This makes it less likely to bend accidentally during surgery, etc.

[0042] (Aspect 3) More preferably, the cauterization puncture needle further includes a covering portion that covers the pipe portion. At least one of the outer surface of the first pipe and the outer surface of the second pipe is covered with the covering portion. The entire area covered by the covering portion is subjected to a matte surface treatment.

[0043] According to the third aspect, by performing a matte surface treatment on the entire area of ​​the first pipe and the second pipe that is covered by the covering portion, the first pipe and the covering portion are closely attached to each other, and wrinkles are less likely to occur in the covering portion, which allows the cauterization puncture needle to be inserted smoothly into the sheath.

[0044] (Aspect 4) More preferably, the outer diameter of the tip electrode portion is larger than the outer diameter of the first pipe and smaller than the outer diameter of the region of the covering portion that covers the first pipe.

[0045] According to the fourth aspect, by making the outer diameter of the tip electrode portion larger than the outer diameter of the first pipe, the electrode surface area of ​​the tip electrode portion can be made larger than in a configuration in which the outer diameter is the same as that of the first pipe. By increasing the electrode surface area, electrically stable cauterization becomes possible and it becomes easier to puncture the intended location. Furthermore, since the step between the tip electrode portion and the covering portion is small, the covering portion is less likely to peel off or roll up.

[0046] (Aspect 5) More preferably, the pipe portion has a straight portion between the first bent portion and the second bent portion, the straight portion being located in a region formed by two layers of the first pipe and the second pipe.

[0047] According to aspect 5, by providing a straight section between two bent sections, it becomes easier to visually confirm the position of the region (second bent section) where fine adjustment is desired. Furthermore, since the straight section is composed of two layers of the first pipe and the second pipe, it is more difficult to bend than a region composed of a single layer. Therefore, the straight section is easier to maintain a straight state and is less likely to bend accidentally during surgery, etc.

[0048] (Aspect 6) More preferably, the first pipe and the second pipe are joined by adhesive bonding on the tip end side and spot welding on the base end side.

[0049] According to the sixth aspect, the adhesive on the tip side can prevent leakage of the liquid passing through the inside of the first pipe. In addition, the spot welding on the base side can ensure electrical continuity to the tip electrode portion and make it difficult for the first pipe and the second pipe to come off. [Explanation of symbols]

[0050] 1 cauterization needle, 10 tip electrode, 11 tube 11a hole, 21 first pipe, 21a first hollow portion, 22 second pipe, 22a second hollow portion, 40 coating layer, 50 operation portion, 51 luer connector, 53 relay cable, 55 syringe connection portion, a1 first region, a2 second region, a3 third region (first straight portion), a4 fourth region (first bent portion), a5 fifth region (second straight portion), a6 sixth region (second bent portion), a7 seventh region (third straight portion), b1 adhesive region, d1 outer diameter of tip electrode portion, d2 outer diameter of first pipe, d3 outer diameter of region of coating layer covering first pipe, NP neutral plane of at least one of first bent portion and second bent portion, s1 to s3 spot welding portion

Claims

1. a pipe section having a first pipe and a second pipe; a tip electrode portion provided at a tip of the first pipe of the pipe portion and through which a high-frequency current is passed, a base end side of the first pipe is inserted into the second pipe, the pipe portion has a first bent portion, a second bent portion, and a straight portion located between the first bent portion and the second bent portion, the first bent portion is located on a tip side of the pipe portion, the second bent portion is located on a base end side of the pipe portion, the first bent portion and the second bent portion are configured such that the radius of curvature of the arc of the first bent portion is equal to or greater than the radius of curvature of the arc of the second bent portion, and the arc of the first bent portion is longer than the arc of the second bent portion. Alternatively, the first bent portion and the second bent portion are configured such that an arc of the first bent portion has a length equal to or greater than an arc of the second bent portion, and a radius of curvature of the arc of the first bent portion is longer than a radius of curvature of the arc of the second bent portion, the first bent portion is located in a region formed by two layers of the first pipe and the second pipe, the second bent portion is located in a region of the second pipe that is configured by a single layer, The cauterization puncture needle, wherein the first bending portion and the second bending portion bend in approximately the same direction.

2. Further provided is a covering portion that covers the pipe portion, At least one of an outer surface of the first pipe and an outer surface of the second pipe is covered by the covering portion, The cauterization and puncture needle according to claim 1 , wherein the entire area covered by the covering portion is subjected to a matte surface treatment.

3. The cauterization and puncture needle according to claim 2 , wherein an outer diameter of the tip electrode portion is larger than an outer diameter of the first pipe and smaller than an outer diameter of a region of the covering portion that covers the first pipe.

4. A cauterization puncture needle as described in any of claims 1 to 3, wherein the straight portion is located in an area formed by the two layers of the first pipe and the second pipe.

5. The cauterization puncture needle according to any one of claims 1 to 4, wherein the first pipe and the second pipe are joined by adhesive bonding on the tip end side and spot welding on the base end side.

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