JP7029454B2 - High frequency treatment tool for endoscopes - Google Patents

Description

The present invention relates to a high frequency treatment tool introduced into a living body via an endoscope. More specifically, the present invention relates to a high-frequency treatment tool for an endoscope, which is provided with a wire-shaped cut portion.

Conventionally, we have introduced a treatment tool that is inserted into the human body, equipped with an objective lens and an illumination lens at the tip, and while observing the inside of the body cavity, a treatment tool that performs treatment inside the body cavity via a treatment tool insertion channel that leads from the hand side to the tip side. There is an endoscope to do. ESD (endoscopic submucosal dissection) and EMR (endoscopic mucosal resection) are known as treatments using such an endoscope.

Treatment tools used through an endoscope include knives and snares. The knife is for making an incision on the surface of the body cavity. In order to perform fine excision work, the knife is stably fixed to the sheath, and it is necessary to reliably transmit the operation by the operation part on the hand side. The snare is provided with a loop-shaped wire, and the ridge on the surface of the body cavity is surrounded by a loop, the loop diameter is reduced, the root of the ridge is narrowed down, and the snare is excised. Since the snare loop wire is squeezed and squeezed at the root of the lesion, the loop wire can be taken in and out of the sheath, and the loop wire needs to be composed of an elastically deformable wire. Both treatment tools are used as high-frequency treatment tools that supply electric power from the hand side and generate an electric current to excise and cauterize the surface of the body cavity.

As a knife used through an endoscope, there is a high frequency treatment tool disclosed in Patent Document 1. The knife comprises a sheath and a needle-like electrode that is provided so as to project from the inside of the sheath and a high frequency current is applied to the tip. This knife is a rigid cylinder with a hole diameter larger than the outer diameter of the knife in the sheath to regulate the amount of protrusion of the knife consisting of needle-shaped electrodes and to ensure the stability of the part of the knife where the incision procedure is performed. Is provided, and a plurality of stopper protrusions are provided at the location on the hand side of the knife. The surface contact between the hard cylinder and the stopper protrusion regulates the protrusion length of the knife from the tip surface of the sheath, and the knife can be stably held on the center of the long axis of the sheath.

As a snare used through an endoscope, there is a high-frequency snare disclosed in Patent Document 2. The snare comprises a sheath and a conductive loop wire that is operably inserted and disposed in the sheath. This snare is provided with a tip electrode at the tip of the sheath in order to reliably cauterize and squeeze the root of the lesion to the center with a high-frequency current without bleeding. Further, in this snare, the tip tip is passed through the tip of the loop wire in order to reduce the degree of stress concentration on the bending back portion of the tip of the loop wire.

The knife is used for ESD (endoscopic submucosal dissection). ESD has the advantage that the lesion can be finely resected by a procedure in which the lesion of the digestive organ is gradually peeled off endoscopically. On the other hand, the procedure takes time and requires the skill of the surgeon. Snares are used for EMR (endoscopic mucosal resection). EMR is a procedure in which a lesion is endoscopically surrounded by a loop and then squeezed to excise it, and a wide area can be easily excised. However, it is difficult to accurately excise only the targeted area, and the shape of the lesion that can be used is limited.

Therefore, first use a knife to make an incision around the targeted lesion and peel it off a small amount, then pull out the knife from the endoscope, replace it with a snare, apply a snare loop to the peeled part with the knife, and apply the lesion. A method of shortening the procedure time while maintaining the accuracy of excision of the lesion by narrowing down the lesion is being studied.

As a treatment tool for use in such a procedure, a tool having a pointed head provided at the tip of a snare loop wire has been proposed. Patent Document 3 discloses a sheath and a high-frequency snare for an endoscope including a snare loop that elastically deforms and narrows when pulled into the sheath. In this snare, an electrically insulating tip is fixedly attached to the tip of the snare loop so that the tip of the wire penetrates, the wire is projected forward from the tip, and the protruding portion is a rod-shaped tip. Use as an electrode. The rod-shaped tip electrode of this snare can be used as a knife. When used as a knife, the snare loop is pulled into the sheath, leaving the tip portion, and only the tip portion protrudes from the sheath and is used as an incision knife.

When ESD is performed using a knife, it is necessary to have a structure in which the tip of the knife does not shake during the procedure in order to finely excise the lesion. Further, in order to reliably transmit the movement of the operation portion at hand to the operation portion at the tip, it is necessary that the tip portion of the knife is stably fixed to the tip portion of the sheath. On the other hand, the treatment part is sheathed regardless of whether it is energized or not, so as not to inadvertently damage the inside of the endoscopic treatment tool insertion channel or body cavity while transporting the treatment tool to the lesion. It is desirable to be able to move along the long axis of the sheath so that it is held inside and can project from the tip of the sheath during treatment.

Also, when using a treatment tool with a knife at the tip of the snare as a knife, the hand side of the knife should be a snare made up of elastically deformable wires, and the snare loop should be expanded after incision at the knife. However, the knife portion needs to be fixed to the sheath tip in consideration of strangulation of the lesion.

As a structure for fixing the knife portion to the sheath, Patent Document 4 discloses a structure in which a frictional resistance imparting member is arranged in the sheath. By crushing the frictional resistance applying member on the inner peripheral surface of the sheath and the outer peripheral surface of the operation wire connected to the knife portion, a load due to the frictional resistance is generated, and the knife portion is fixed when the knife is used.

Japanese Unexamined Patent Publication No. 2007-044393 Japanese Unexamined Patent Publication No. 11-347045 Japanese Unexamined Patent Publication No. 2010-131100 Japanese Unexamined Patent Publication No. 2007-319424

In the high frequency knife shown in Patent Document 1, in order to fix the knife to the tip of the sheath, a hard cylinder is provided on the sheath and a stopper protrusion is provided on the knife. The knife is fixed by the surface contact between the hard cylinder and the stopper. With such a configuration, the number of parts of the treatment tool will increase. Further, since the knife is completely fixed by the surface contact between the hard cylinder and the stopper, the knife cannot be projected any further after protruding from the sheath tip surface for a predetermined length.

Since the high-frequency snare shown in Patent Document 2 is not planned to use the tip electrode as a knife, there is no disclosure about the fixing mechanism of the tip electrode.

In the high-frequency snare shown in Patent Document 3, the tip knife portion is fixed by contact between the tip and the tip of the sheath. The electrically insulating tip is provided in the snare loop on the tip side of the sheath tip surface. Therefore, when the treatment is performed in the body cavity using the tip knife portion, the knife portion is not pulled into the sheath because the sheath tip surface and the tip tip come into contact with each other, and the knife position can be stabilized. .. However, when the treatment tool is inserted into the treatment tool insertion channel of the endoscope or when the treatment tool is located in the non-treatment part in the body cavity, the knife part is always exposed from the sheath, so that it is not energized. Even at times, there is a risk of damaging the surroundings.

In Patent Document 4, an elastic friction resistance imparting member having elasticity is press-fitted and arranged in the vicinity of the tip of the sheath in a state of being crushed and elastically deformed by the inner peripheral surface of the sheath and the outer peripheral surface of the operation wire. Treatment tools for endoscopy are disclosed. In the treatment tool, the protrusion length of the tip treatment piece from the tip of the sheath is set to an arbitrary length by allowing frictional resistance to act between the operation wire, the elastic friction resistance imparting member, and the flexible sheath. It can be adjusted and maintained in a stable manner. Further, Patent Document 4 discloses that a region of the friction resistance imparting member that does not come into contact with the operation wire is subjected to surface treatment in order to increase the frictional resistance with the sheath. In the knife fixing method shown in Patent Document 4, not only when a knife is used, but also in all a series of operations such as projecting the knife out of the sheath and storing the knife, there is an inconvenience that the handle operation becomes heavy. In addition, the number of parts increases, and it is necessary to take measures to fix the friction resistance imparting member or prevent the friction resistance imparting member from coming out of the sheath.

By the way, when actually performing the procedure using the treatment tool, if the knife part is inserted into the tissue for incision and buried, if the sheath always has the same appearance in the longitudinal direction, how much it will be buried in the tissue. It becomes difficult to judge whether it is. Therefore, the treatment tool may be pressed too much against the tissue, resulting in a risk of perforation of the tissue.

The present invention has been made in view of these problems, and is a high-frequency treatment for an endoscope having a structure capable of stably fixing the knife portion in a treatment tool having a knife portion at the tip of the snare. The purpose is to provide the ingredients.

The high-frequency treatment tool for an endoscope of the present invention has the following configurations in order to solve the above-mentioned problems. The high-frequency treatment tool for an endoscope of the present invention has a sheath, a linear object arranged in the sheath, and a first wire portion and a second wire portion extending in the perspective direction of the sheath, respectively. A conductive wire having a proximal end of the first wire portion and a proximal end of the second wire portion fixed to a linear object, and a distal end portion of the first wire portion and a second wire. It is provided with a conductive tip tip connected to each of the distal ends of the portion and a conductive connector for connecting the linear object to the first wire portion and the second wire portion, and a part of the inner wall of the sheath is a surface. It has a treated surface treated portion and is characterized in that at least one of a conductive connector, a first wire portion, a second wire portion and a conductive tip is in contact with the surface treated portion. In the high-frequency treatment tool for endoscopes of the present invention, at least one of the conductive connector, the first wire portion, the second wire portion, and the conductive tip tip is provided in a state where a part of the conductive tip tip protrudes from the sheath. One is in contact with the surface-treated portion of the sheath. In this way, the parts arranged in the sheath are in contact with the surface-treated portion of the sheath, so that the conductive tip tip is stably fixed to the sheath tip and only the conductive tip tip is sheathed. Can be projected from.

According to the high-frequency treatment tool for endoscopes of the present invention, a conductive tip tip as a knife portion is provided at the tip of the snare, and the conductive tip tip is stably fixed to the tip of the sheath, so that the treatment tool can be used as a knife. When used, only the conductive tip can be projected from the sheath.

It is a top view of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is an enlarged view of the tip part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which showed the structure of the sheath of the high frequency treatment tool for an endoscope which concerns on one Embodiment of this invention, and the component arranged in the sheath. It is sectional drawing which showed the structure of the sheath of the high frequency treatment tool for an endoscope which concerns on one Embodiment of this invention, and the component arranged in the sheath. It is an enlarged view of the tip part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which shows the sheath surface-treated part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which shows the sheath surface-treated part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which shows the sheath surface-treated part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which shows the sheath surface-treated part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which shows the sheath surface-treated part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which shows the sheath surface-treated part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which shows the sheath surface-treated part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention. It is sectional drawing which shows the sheath surface-treated part of the high frequency treatment tool for an endoscope which concerns on one Example of this invention.

The high-frequency treatment tool for an endoscope of the present invention is inserted into a treatment tool insertion channel of an endoscope and is used for treatments such as marking, incision, and strangulation in a body cavity, and surgical procedures such as ESD and EMR. be. The high frequency treatment tool has a knife portion and a snare portion on the distal side. When the high-frequency treatment tool is used as a knife, only the knife portion at the tip can be stably projected from the tip of the sheath, and when used as a snare portion, for example, a conductive wire formed in a loop shape is used as the snare portion. It can be projected from the sheath. Hereinafter, the high-frequency treatment tool for an endoscope may be simply referred to as a “treatment tool”.

As shown in FIGS. 1 and 2, the high-frequency treatment tool for an endoscope of the present invention extends in the perspective direction of the sheath 5, the wire 4 arranged in the sheath 5, and the sheath 5. It has a first wire portion 2A and a second wire portion 2B, and the proximal end portion of the first wire portion 2A and the proximal end portion of the second wire portion 2B are fixed to the linear object 4. The conductive wire 2, the conductive tip tip 1 connected to the distal end of the first wire portion 2A and the distal end of the second wire portion 2B, respectively, the linear object 4 and the first wire portion 2A. It is provided with a conductive connector 3 that connects the second wire portion 2B and the second wire portion 2B. The high-frequency treatment tool for an endoscope of the present invention has a surface-treated portion on a part of the inner wall of the sheath 5, and has a conductive connector 3, a first wire portion 2A, and a second wire portion 2B. And at least one of the conductive tip chips 1 is accessible to the surface treated portion. Conductive connector 3, first wire portion 2A, second wire connecting the linear object 4, the first wire portion 2A, and the second wire portion 2B with a part of the conductive tip tip 1 protruding from the sheath 5. At least one of the portion 2B and the conductive tip tip 1 is in contact with the surface-treated portion of the inner wall of the sheath 5. In this way, the parts arranged in the sheath 5 are in contact with the surface-treated portion of the inner wall of the sheath 5, so that the conductive tip tip 1 is stably fixed by the tip of the sheath 5. , Only the conductive tip 1 can be projected from the sheath 5. The distal side is the distal end side inserted into the body cavity of the endoscope, and the proximal side is the opposite side to this, and refers to the hand side for operating the endoscope and the treatment tool. .. Unless otherwise specified, the "length" refers to the length of the sheath in the perspective direction (the long axis direction of the sheath). Hereinafter, the "conductive connector" may be referred to as a "connector", the "conductive wire" may be referred to as a "wire", and the "conductive tip tip" may be referred to as a "tip tip".

The sheath 5 is a long hollow member capable of accommodating the linear object 4 and the conductive wire 2 inside. The inner surface of the sheath 5 is in contact with at least one of the conductive connector 3, the conductive wire 2, and the conductive tip 1 housed inside the sheath 5, and the conductive connector 3, the conductive wire 2, and the conductive tip 1 are in contact with each other. Properties It has a surface property and strength sufficient to fix the tip tip 1. In addition, the sheath 5 reliably reaches the tissue to be treated, with surface slippage that allows it to penetrate the endoscopic treatment instrument insertion channel, flexibility that bends along the shape of the treatment instrument insertion channel lumen, and so on. It is desirable to have a good balance of rigidity.

The material of the sheath 5 is, for example, a tubular body formed of a coiled metal or a synthetic resin, a tubular body formed by connecting a plurality of short tubular joint pieces in the long axis direction and making them rotatable, or a synthetic resin. The formed cylinder is used. Examples of the synthetic resin forming the sheath include polyamide resins such as nylon, polyolefin resins such as polypropylene (PP) and polyethylene (PE), polyester resins such as polyethylene terephthalate (PET), and polyetheretherketone (PEEK). Fluororesin such as aromatic polyetherketone resin, polyimide resin, polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), etc. Can be used.

The length of the sheath 5 can be appropriately set according to the length of the endoscope to be used in combination, and is generally 1650 mm to 2300 mm in many cases. The outer diameter of the sheath 5 is preferably 1.8 mm or more and 3.5 mm or less, and the inner diameter of the sheath 5 is preferably 1.2 mm or more and 3.0 mm or less. The flexibility and rigidity of the sheath 5 can be controlled not only by the material of the sheath but also by the thickness. The thickness of the sheath 5 can be selected depending on the material used, but when the material of the sheath is fluororesin, the thickness is preferably 0.2 mm or more on one side.

The outer diameter and inner diameter of the sheath 5 may be constant, may be tapered, or may have a plurality of different diameters along the longitudinal direction. FIG. 3 shows a configuration example of a tip portion of a treatment tool having a constant inner diameter of the sheath 5, and FIG. 4 shows a configuration example of a tip portion of a treatment tool having a non-constant inner diameter of the sheath 5. 3 and 4 show an example of a treatment tool in which a part of the conductive tip 1 protrudes from the sheath 5 and the wire 2 is housed inside the sheath 5.

In the high frequency treatment tool for endoscopes, at least the distal end of the conductive tip tip 1 is arranged distal to the distal end of the sheath 5, and the proximal side of the conductive tip tip 1 is arranged inside the sheath 5. In this state, the surface treatment is applied to the portion where any one or more of the conductive connector 3, the conductive wire 2, and the conductive tip tip 1 come into contact with the inner wall of the sheath 5. As a result, when a part of the conductive tip tip 1 protrudes from the sheath 5, the conductive tip tip 1 is more stably fixed by the contact between the component arranged in the sheath 5 and the inner wall of the sheath 5. be able to. That is, the state in which the conductive tip tip 1 is projected due to the contact between any one or more of the conductive connector 3, the conductive wire 2, and the conductive tip tip 1 and the surface-treated portion of the inner wall of the sheath 5 is obtained. It can be kept stable. Details of the surface-treated portion will be described later.

The linear object 4 is a long object arranged in the sheath 5 (see FIG. 1). The linear object 4 is connected to the handle 6 and the conductive wire 2 to move the conductive wire 2 inside and outside the sheath 5, and is used to transmit the rotation operation on the handle 6 side to the conductive wire 2 side. .. As the conductive wire 2 moves, the linear object 4 may move out of the sheath 5.

The linear object 4 housed in the sheath 5 is preferably made of an elastically deformable material. The elasticity of the linear object 4 is sufficient as long as the elasticity changes along the sheath 5 that follows the deformation of the treatment tool insertion channel of the endoscope. The linear object 4 is not particularly limited as long as it is a material that can be elastically deformed, but is a superelastic alloy such as a Ni—Ti alloy, a metal such as stainless steel such as SUS303 and SUS304, and a resin such as a polyamide resin such as nylon. Can be used. The linear object 4 may be formed of one member, or a plurality of members may be joined in the middle of the linear object 4 in the long axis direction. When joining in the middle, the wires may be joined by a normal joining method. As a joining method, for example, there are methods such as caulking and joining with a metal pipe, welding, welding and bonding. The linear object 4 may be a single wire or a stranded wire obtained by twisting the single wires. If it is a single wire, it is easy to manufacture. If it is a stranded wire, the strength of the linear object 4 can be increased, so that an operation such as rotation on the handle 6 side can be more reliably transmitted to the tip portion. The length of the linear object 4 needs to be longer than the treatment tool insertion channel of the endoscope.

The conductive wire 2 is a long object extending in the perspective direction, and is used as a snare of a treatment tool by exposing at least a part thereof from the distal side of the sheath 5. The conductive wire 2 has a first wire portion 2A and a second wire portion 2B extending in the perspective direction of the sheath 5, respectively, and has a proximal end portion of the first wire portion 2A and a second wire portion. The proximal end of portion 2B is fixed to the linear object 4. The proximal end of the first wire portion 2A and the proximal end of the second wire portion 2B are directly connected to the linear object 4 as long as they are fixed to the linear object 4. It may be joined indirectly. Each proximal end of the first wire portion 2A and the second wire portion 2B includes the proximal end of the first wire portion 2A or the second wire portion 2B, and may be, for example, a portion within 30 mm from the proximal end. It is preferable, more preferably a portion within 20 mm. Further, each distal end portion of the first wire portion 2A and the second wire portion 2B includes the distal end of the first wire portion 2A or the second wire portion 2B, and is, for example, a portion within 30 mm from the distal end. It is preferable, and more preferably, it is a portion within 20 mm.

As shown in FIGS. 3 and 4, at least the distal end of the conductive tip tip 1 is located distal to the distal end of the sheath 5, and the proximal side of the conductive tip tip 1 is located inside the sheath 5. It is preferable that at least one portion of the first wire portion 2A is in contact with the inner wall of the sheath 5 and at least one portion of the second wire portion 2B is in contact with the inner wall of the sheath 5. As a result, the conductive tip 1 is stably fixed by the tip of the sheath 5.

In the conductive wire 2, the first wire portion 2A and the second wire portion 2B may be formed line-symmetrically with respect to a line extending in the perspective direction of the sheath 5, or may be formed asymmetrically. The shape of the conductive wire 2 is preferably a loop shape, and above all, a loop shape in which both ends are fixed to the distal ends of the linear object 4 is preferable. The loop shape means, for example, an annular shape in which the snare portion including the knife portion is closed, and can be circular, elliptical, polygonal, or the like. The shape can be changed by providing a bent portion described later by folding or bending the middle of the wire 2. For example, by bringing a part of the wire 2 into contact with the sheath 5, the conductive tip 1 connected to the conductive wire 2 can be fixed so as to protrude from the tip of the sheath 5.

It is preferable that the conductive wire 2 is in contact with the sheath 5 at one location each of the first wire portion 2A and the second wire portion 2B. This is because the wire can be more firmly fixed to the sheath 5 when the tip tip 1 is projected from the sheath 5. A plurality of points may be in contact with the sheath 5 at the proximal side or the portion between the distal side and the proximal side of the wire 2. Since the loop-shaped wire 2 has a loop diameter larger than the inner diameter of the sheath 5, when the wire 2 is housed in the sheath 5, the loop is folded and a plurality of points of the wire 2 come into contact with the sheath 5. It is preferable that the first wire portion 2A and the second wire portion 2B are in contact with the sheath 5 substantially line-symmetrically with respect to the long axis direction of the sheath 5.

It is preferable that the conductive wire 2 has the first wire portion 2A and the second wire portion 2B integrally formed at the distal end portion. This makes it possible to simplify the configuration of the conductive wire 2. Alternatively, in the conductive wire 2, the first wire portion 2A and the second wire portion 2B may be separate members. As a result, the degree of freedom in snare design can be increased, for example, the materials constituting the first wire portion 2A and the second wire portion 2B are made different to complicate the shape of the snare.

The conductive wire 2 fixed to the linear object 4 is preferably made of a material that is conductive and elastically deformable. The elasticity of the conductive wire 2 needs to be such that after protruding from the tip of the sheath 5, it is restored to, for example, a loop shape, which is planned as a snare. Further, the wire 2 is preferably made of a material that can be easily bent so that a bent portion can be appropriately provided. As the material of the conductive wire 2, it is preferable to use a superelastic alloy such as Ni—Ti alloy or a metal such as stainless steel such as SUS303 and SUS304.

The length and diameter of the conductive wire 2 can be appropriately selected depending on the use of the snare. The length of the conductive wire 2 is preferably 60 mm or more and 200 mm or less. Of these, the length of the connecting portion with the linear object 4 is preferably 2 mm or more and 10 mm or less. The diameter of the conductive wire 2 is preferably 0.2 mm or more and 1.0 mm or less.

The linear object 4 and the conductive wire 2 can be connected by a usual joining method, and may be directly connected or may be connected via a connecting member. As a joining method, for example, there are methods such as caulking and joining with a metal pipe, welding, welding and bonding. When connecting both ends of the elastically deformable metal wire to the linear object 4, it is preferable to connect them via a metal tube.

The conductive connector 3 can be provided at the connection portion between the above-mentioned linear object 4 and the conductive wire 2. The conductive connector 3 may be a connecting member used for connecting the linear object 4 and the conductive wire 2, and is a conductive member provided near the connecting portion on the proximal end side of the conductive wire 2. May be good. The conductive connector 3 is preferably made of a metal material such as stainless steel such as SUS303 and SUS304. The shape of the conductive connector 3 can be spherical, elliptical spherical, polyhedral, columnar, conical, or a combination thereof, or the entire length can be bent or widened. The length of the sheath 5 of the conductive connector 3 in the perspective direction is preferably 2.0 mm or more and 10.0 mm or less.

A conductive connector in a state where at least the distal end of the conductive tip 1 is located distal to the distal end of the sheath 5 and the proximal side of the conductive tip 1 is located inside the sheath 5. It is preferable that 3 is in contact with the sheath 5. The portion of the conductive connector 3 in contact with the sheath 5 is preferably at least the tip side of the conductive connector 3, and more preferably the entire length. This is because the wire 2 can be more firmly fixed to the sheath 5 when the tip tip 1 is projected from the sheath 5. The conductive connector 3 may be entirely composed of a conductive material, a part thereof may be composed of a conductive material, and the other portion may be composed of a non-conductive material. The connector 3 may be formed so as to ensure conductivity between the linear object 4 and the wire 2. For example, the connecting tool 3 may have a structure in which the outer surface is made of a conductive material and the conductive material is in contact with the sheath 5, or the outer surface of the connecting tool 3 is made of a non-conductive material, and the non-conductive material is the sheath 5. It may be a structure in contact with.

The tip tip 1 has a portion used as a high-frequency knife, that is, a knife portion. The tip tip 1 is connected to the distal end of the first wire portion 2A and the distal end of the second wire portion 2B, respectively. The tip 1 is made of a conductive material. The tip 1 is preferably made of a metal material such as stainless steel such as SUS303 and SUS304. The shape of the tip tip 1 can be appropriately selected according to the application of the knife. For example, the shape may be spherical, elliptical spherical, columnar, conical, or a combination thereof, or the tip side may be bent or widened. The length of the sheath 5 of the tip tip 1 in the perspective direction can be appropriately selected depending on the application of the treatment tool and the length of protrusion of the sheath 5 from the tip surface, but is 2.0 mm or more and 5.0 mm or less. It is preferable to have. The conductive tip 1 is arranged on the most distal side of the treatment tool.

The conductive wire 2 and the tip tip 1 can be connected by a usual connecting method, and may be directly connected or may be connected via another member. For example, there are methods such as caulking and bonding with a metal tube, welding, welding and bonding. Above all, it is preferable that the conductive tip tip 1 has an opening, and the conductive tip tip 1 and the conductive wire 2 are connected by locating a part of the conductive wire 2 in the opening. As a result, the conductive chip 1 and the conductive wire 2 are efficiently connected. More preferably, an opening is provided on the proximal side of the tip tip 1, and a part of the conductive wire 2 is located in the opening to connect the conductive tip tip 1 and the conductive wire 2.

The opening can be formed by providing a through hole or a recess in the tip tip 1. As shown in FIG. 2, when the opening is a through hole 11, the risk that the tip 1 is dropped during the procedure can be reduced, and when the opening is a dent, the manufacturing can be simplified. In particular, in the embodiment in which the tip tip 1 is provided with a through hole 11 and the conductive wire 2 and the tip tip 1 are connected by inserting the conductive wire 2 through the through hole 11, the wire 2 is at the distal end portion. , Is preferably adopted when the first wire portion 2A and the second wire portion 2B are integrally formed. On the other hand, when the first wire portion 2A and the second wire portion 2B of the conductive wire 2 are separate members, it is preferable that the conductive wire 2 and the tip tip 1 are connected by welding, welding, or adhesion.

The tip 1 may be rotatable with respect to the conductive wire 2, may be movable along the major axis direction of the wire 2, or may be completely fixed. The major axis direction of the wire 2 means a direction along the wire 2. The fact that the tip tip 1 can move along the long axis direction of the wire 2 means that when the wire 2 has a circular shape in which both ends are fixed to the linear object 4, the tip tip 1 moves along the circumferential direction of the circle. It means that it is possible.

The depth direction of the opening of the tip tip 1 is preferably different from the perspective direction of the sheath 5, and more preferably the direction perpendicular to the perspective direction of the sheath 5. As a result, the tip tip 1 can be arranged on the distal side of the conductive wire 2.

As shown in FIG. 5, the opening of the tip tip 1 may be provided as an insertion passage through which the wire 2 is inserted. In FIG. 5, the inlet and outlet of the insertion passage are provided on the proximal end surface of the tip tip 1. As a result, a part of the wire 2 can be arranged in a direction perpendicular to the perspective direction of the sheath 5.

The tip tip 1 is arranged in a state where at least the distal end of the conductive tip tip 1 is located distal to the distal end of the sheath 5 and the proximal side of the conductive tip tip 1 is located inside the sheath 5. It is preferable to be in contact with the sheath 5. The portion of the tip tip 1 in contact with the sheath 5 is preferably the end of the knife portion of the tip tip 1, that is, the proximal side of the tip tip 1. This is because the wire 2 can be more firmly fixed to the sheath 5 when the tip tip 1 is projected from the sheath 5. The tip chip 1 may be entirely composed of a conductive material, a part thereof may be composed of a conductive material, and the other portion may be composed of a non-conductive material. The tip tip 1 may be formed so as to ensure conductivity between the wire 2 and the knife portion. The tip 1 may have a structure in which, for example, the outer surface is made of a conductive material and the conductive material is in contact with the sheath 5, and the outer surface on the proximal side of the tip 1 is made of a non-conductive material. The structure may be such that the material is in contact with the sheath 5.

By making both the wire 2 used as a snare and the tip tip 1 used as a knife conductive, when the treatment tool of the present invention is used as a snare, there is no non-conductive part on the distal side of the wire 2 and it is efficient. Can be squeezed and cauterized.

The wire 2 may be provided with a bent portion. As a result, the shape of the snare can be appropriately designed according to the size and shape of the lesion and the type of procedure, the conductive tip 1 is reliably projected, and the tip of the sheath 5 is stably fixed. can do. The bent portion is formed, for example, by bending a wire or joining two or more wires at an angle. Only one bent portion may be provided, or a plurality of bent portions may be provided. Further, the bent portion may be formed in a polygonal line shape or may be formed in a curved shape.

As shown in FIG. 2, it is preferable that the wire 2 has a first bent portion 22 in the first wire portion 2A and a second bent portion 23 in the second wire portion 2B. By providing the bent portion on the wire 2 in this way, the degree of freedom in designing the shape of the snare of the treatment tool is increased, the conductive tip 1 is reliably projected, and the tip of the sheath 5 is stably fixed. Can be done. In FIG. 2, the first bent portion 22 and the second bent portion 23 are provided on the distal side of the center of the wire 2 in the perspective direction.

When the wire 2 is housed in the sheath 5, it is preferable that the first bent portion 22 and the second bent portion 23 are in contact with the inner wall of the sheath 5. As a result, the wire 2 can be more stably fixed by the inner wall of the sheath 5.

When the wire 2 is exposed to the outside of the sheath 5, the first bent portion 22 and the second bent portion 23 are preferably formed so as to be convex inward in the radial direction of the sheath 5. As a result, the wires 2 are radially outward in the first wire portion 2A on the proximal side of the first bent portion 22 and in the second wire portion 2B on the proximal side of the second bent portion 23. It becomes easy to extend, and the diameter of the snare in the direction perpendicular to the perspective direction of the sheath 5 can be increased. The fact that the bent portion is convex inward in the radial direction of the sheath 5 means that the convex portion of the bent portion is arranged toward the inside of the sheath 5. The fact that the wire 2 is convex outward in the radial direction of the sheath 5 means that the wire 2 has a loop shape that bulges outward and spreads out.

The perspective positions of the first bent portion 22 and the second bent portion 23 can be appropriately set according to the shape of the snare, but at least one of the first bent portion 22 and the second bent portion 23 is the wire 2. It is preferable that the first bending portion 22 and the second bending portion 23 are provided at the distal end portion, and it is more preferable that both the first bending portion 22 and the second bending portion 23 are provided at the distal end portion. As a result, the diameter of the snare can be increased in a relatively wide range in the perspective direction of the sheath 5. The bent portion of the conductive wire 2 can be provided with an arbitrary number of bent portions at an arbitrary position according to the required snare performance.

A surface-treated portion is provided on a part of the inner wall of the sheath 5. The high frequency treatment tool is a conductive connection in a state where at least the distal end of the tip tip 1 is located distal to the distal end of the sheath 5 and the proximal side of the tip tip 1 is located inside the sheath 5. At least one of the tool 3, the first wire portion 2A, the second wire portion 2B, and the tip tip 1 comes into contact with the surface-treated portion. As a result, the high-frequency treatment tool can stably maintain the state in which the conductive tip 1 is projected.

6 to 13 show various configuration examples of the sheath 5 provided with the surface-treated portion 7. In FIG. 6, the inner diameter of the sheath 5 is formed to be constant in the major axis direction, and the first wire portion 2A and the second wire portion 2B are surface-treated with a part of the tip tip 1 protruding from the sheath 5. An aspect of contact with the portion 7 is shown. FIG. 7 shows an embodiment in which the inner diameter of the sheath 5 is formed to be constant in the major axis direction, and the tip tip 1 comes into contact with the surface-treated portion 7 in a state where a part of the tip tip 1 protrudes from the sheath 5. ing. FIG. 8 shows an embodiment in which the inner diameter of the sheath 5 is formed to be constant in the major axis direction, and the conductive connector 3 comes into contact with the surface-treated portion 7 in a state where a part of the tip tip 1 protrudes from the sheath 5. It is shown. In FIGS. 9, 12 and 13, the sheath 5 is provided with a small diameter portion, and the first wire portion 2A and the second wire portion 2B have a small diameter portion in a state where a part of the tip tip 1 protrudes from the sheath 5. An aspect of contact with the surface-treated portion 7 is shown. FIG. 10 shows a mode in which the sheath 5 is provided with a small diameter portion, and the tip tip 1 is in contact with the surface-treated portion 7 of the small diameter portion in a state where a part of the tip tip 1 protrudes from the sheath 5. FIG. 11 shows a mode in which the sheath 5 is provided with a small diameter portion, and the conductive connector 3 is in contact with the surface-treated portion 7 in a state where a part of the tip tip 1 protrudes from the sheath 5.

It is preferable that the surface-treated portion 7 of the sheath 5 has a larger frictional resistance than the untreated portion. As a result, the force for fixing the parts arranged in the sheath 5 to the surface-treated portion 7 becomes larger than in the non-treated state, and the conductive tip tip 1 can be stably fixed by the tip of the sheath 5. The surface-treated portion 7 is preferably provided at least in a portion within 100 mm from the distal end of the sheath 5, and more preferably provided only in a portion within 100 mm from the distal end of the sheath 5. Further, in the sheath 5, it is preferable that a portion having a larger frictional resistance than the untreated portion is formed in such a region.

In order to increase the frictional resistance of the inner wall of the sheath 5, there are methods such as roughening and imparting adhesiveness. For example, the surface of the sheath 5 can be chemically or physically treated to impart hydrophilic groups such as hydroxyl groups, carboxyl groups, and carbonyl groups to impart adhesiveness to the surface of the sheath 5, or the surface of the sheath 5 can be imparted. The slipperiness of the material can be reduced. Examples of such treatment include tetraetch (registered trademark) treatment, fluorobonder (registered trademark) treatment, and plasma treatment. For example, if a tetraetch treatment or a fluorobonder treatment is used, a hydrophilic group can be imparted to the surface of the fluororesin, and if a plasma treatment is used, a polyamide resin, a polyolefin resin, a polyester resin, an aromatic polyetherketone resin, or a polyimide can be used. A hydrophilic group can be imparted to the surface of a resin or the like. Therefore, in this case, it is preferable that the surface-treated portion 7 of the sheath 5 is made of a resin having a hydrophilic group on the surface. On the other hand, as a method of roughening the surface of the sheath 5, an etching treatment, a blast treatment, or the like can be used.

The surface-treated portion 7 of the sheath 5 has a different appearance than the non-treated portion, and the surface-treated portion 7 of the sheath 5 preferably has a different appearance from the non-treated portion. Changes in appearance include coloration, loss of color, transparency, turbidity, as well as changes in outer diameter and roughening of the surface. This can serve as a marker as a measure of the amount of burial in the tissue. When the colors are different, it is important that there is a difference from the non-treated portion, and it may be translucently colored or may be non-transparently colored. If the sheath 5 is originally colored, it can function even if the color is different depending on the surface treatment, the color becomes lighter, or the sheath 5 becomes transparent. When the sheath 5 originally has a plurality of colors, the function can be achieved by mixing the colors only in the surface-treated portion 7. In addition, the function can be fulfilled even if the outer diameter is changed by the surface treatment. The outer diameter may be large or small. When it becomes large, the wall thickness of the sheath 5 is preferably 0.5 mm or less, and when it becomes small, the wall thickness of the sheath 5 is preferably not 0.2 mm or less. In addition, the surface treatment roughens the surface of the sheath 5 and changes the appearance, so that the function can be fulfilled. The portion having a different appearance from the untreated portion due to the surface treatment is preferably formed within 100 mm from the distal end of the sheath 5, and may be formed only within 100 mm from the distal end of the sheath 5. More preferred.

The surface-treated portion 7 is preferably a portion that has been subjected to one or more of a hydrophilic group-imparting treatment, an etching treatment, and a blasting treatment. As a result, the appearance can be changed and the frictional resistance can be stably increased, and the conductive tip 1 can be stably fixed to the tip of the sheath 5. In addition, it can also serve as a marker as a guide for measuring the amount of burial in the procedure portion of the treatment tool. By combining a plurality of methods, it is possible to make the change / difference in appearance of the surface-treated portion 7 and the increase in frictional resistance remarkable. Further, the change in appearance of the surface-treated portion 7 and the increase in frictional resistance may be carried out by different methods. As a result, the color change portion and the frictional resistance increase portion can be separated inside and outside the sheath 5, and the length of the surface treatment portion 7 can be changed to each, so that the degree of freedom in design can be increased. Examples of the hydrophilic group imparting treatment include a tetra etch treatment, a fluorobonder treatment, a plasma treatment, and the like, as described above. If the sheath 5 before the treatment is transparent by the tetra-etch treatment or the fluorobonder treatment, the sheath 5 is colored brown after the treatment. By etching treatment, blast treatment, and plasma treatment, the sheath 5 becomes cloudy after the treatment and is colored translucent white.

The surface-treated portion 7 is preferably a portion including the distal end of the sheath 5. This saves time and effort when performing surface treatment and simplifies surface treatment. It is difficult to perform the surface treatment locally inside and outside the sheath 5, such as by immersing it in a chemical solution, exposing it to light, or hitting it with fine particles. For example, in order to prevent the surface treatment from reaching the distal end of the sheath 5, it takes time and effort to coat the distal end. Therefore, since the surface treatment is applied to the portion including the distal end of the sheath 5, it is possible to save the trouble of protecting the distal end and simplify the treatment.

The position of the surface-treated portion 7 provided on the sheath 5 is such that a part of the tip tip 1 protrudes from the sheath 5, the connector 3, the wire 2 including the first wire portion 2A and the second wire portion 2B, and the tip tip. It is preferable that 1 covers all the points in contact with the sheath 5. Therefore, in a state where at least the distal end of the tip tip 1 is arranged distal to the distal end of the sheath 5 and the proximal side of the tip tip 1 is arranged inside the sheath 5, the fitting 3 and the first It is preferable that all of the wire portion 2A, the second wire portion 2B, and the tip tip 3 are in contact with the surface-treated portion 7. Thereby, when the tip tip 1 is fixed to the tip of the sheath 5, it can be fixed more firmly.

The diameter of the conductive connector 3 in the direction perpendicular to the longitudinal direction of the sheath 5 and the diameter of the conductive tip tip 1 in the direction perpendicular to the longitudinal direction of the sheath 5 are not particularly limited. Either or both of the diameter of the conductive connector 3 in the direction perpendicular to the longitudinal direction of the sheath 5 and the conductive tip 1 in the direction perpendicular to the longitudinal direction of the sheath 5 may be smaller than the inner diameter of the sheath 5. Alternatively, either or both the diameter of the conductive connector 3 in the direction perpendicular to the longitudinal direction of the sheath 5 and the diameter of the conductive tip tip 1 in the direction perpendicular to the longitudinal direction of the sheath 5 are larger than the inner diameter of the sheath 5. It may be a structure. The inner diameter of the sheath 5 at this time means an inner diameter in a state where the sheath 5 is unloaded, that is, a load is not applied from the inside or the outside of the sheath 5. The longitudinal direction of the sheath 5 is the same as the major axis direction of the sheath 5.

The diameter of the conductive connector 3 in the direction perpendicular to the longitudinal direction of the sheath 5 and / or the diameter of the conductive tip tip 1 in the direction perpendicular to the longitudinal direction of the sheath 5 is from the inner diameter of the sheath 5 or the smaller diameter portion of the sheath 5. It is preferably large, and the excess is preferably within 0.5 mm. If the excess is too large, the sheath 5 is likely to be deformed, and the conductive tip 1 may not be stably fixed to the tip of the sheath 5. The diameter of the conductive connector 3 and the diameter of the conductive tip 1 may be the same or different.

It is preferable that the size of the inner diameter of the sheath 5 is not constant in the long axis direction. That is, it is preferable that the size of the inner diameter of the sheath 5 changes in the long axis direction, and a small diameter portion is provided in a part of the sheath 5 in the long axis direction. In this case, at least one of the conductive connector 3, the first wire portion 2A, the second wire portion 2B, and the tip tip 1 is in contact with the small diameter portion in a state where a part of the tip tip 1 protrudes from the sheath 5. This makes it possible to keep the conductive tip 1 protruding more stably. More preferably, the small diameter portion of the sheath 5 is provided on the surface-treated portion 7.

When the size of the inner diameter of the sheath 5 changes along the major axis direction, the sheath 5 is provided with a small diameter portion and a large diameter portion. In this case, the inner diameter of the sheath 5 may be continuously reduced from the large diameter portion to the small diameter portion from the proximal side to the distal side of the sheath 5, or may be discontinuously reduced. In the former case, as shown in FIGS. 4 and 13, the sheath 5 is provided with a tapered portion 52 whose inner diameter gradually changes between the large diameter portion 53 and the small diameter portion 51. In the latter case, as shown in FIGS. 9 to 12, the inner diameter of the sheath 5 changes stepwise in the range from the large diameter portion to the small diameter portion. When the inner diameter of the sheath 5 changes in a stepped manner, it is possible to make two or more steps from the large diameter portion to the small diameter portion. For example, the sheath 5 may have a large diameter portion, a medium diameter portion, and a small diameter portion. It is preferable that the inner diameter of the sheath 5 is formed substantially constant in the major axis direction in the small diameter portion and the large diameter portion (or further, the medium diameter portion).

The sheath 5 preferably has a tapered portion whose inner diameter is not constant. In the tapered portion, it is preferable that the inner diameter of the sheath 5 gradually decreases toward the distal side. In this case, it is preferable that at least one of the first wire portion 2A and the second wire portion 2B is in contact with the inner wall of the sheath 5 at the tapered portion. When the wire 2 is pulled into the sheath 5, the first wire portion 2A and the second wire portion 2B come into contact with the inner wall of the sheath 5 at the tapered portion, so that the conductive tip tip 1 is stabilized at the tip of the sheath 5. Only the conductive tip 1 can be projected from the sheath 5. More preferably, at least one portion of the first wire portion 2A is in contact with the inner wall of the sheath 5 at the tapered portion, and at least one portion of the second wire portion 2B is in contact with the inner wall of the sheath 5 at the tapered portion. Thereby, the conductive tip 1 can be more stably fixed to the tip of the sheath 5.

It is preferable that the small diameter portion and the tapered portion of the sheath 5 are provided on the distal side of the center of the sheath 5 in the perspective direction. As shown in FIGS. 4 and 13, it is preferable that the inner diameter of the sheath 5 decreases toward the distal side in the tapered portion 52. As a result, the conductive wire 2 easily comes into contact with the inner wall of the sheath 5 at the tapered portion 52 of the sheath 5, so that the conductive wire 2 can be stably fixed by the tapered portion 52 of the sheath 5. The length of the small diameter portion is preferably, for example, more than 0 mm and 5.0 mm or less. The length of the tapered portion is preferably more than 0 mm and 5.0 mm or less, for example. The total length of the small diameter portion and the tapered portion is preferably 1.0 mm or more and 5.0 mm or less, for example.

The tapered portion 52 is preferably arranged on the most recent side (more preferably, the latest side) of the small diameter portion 51. In that case, it is preferable that the tapered portion 52 communicates with the large diameter portion 53. As a result, the conductive wire 2 can easily come into contact with the inner wall of the sheath 5 at both the small diameter portion 51 and the tapered portion 52, so that the conductive wire 2 can be fixed more stably. It is preferable that the inner diameter of the sheath 5 increases sequentially from the distal side to the small diameter portion 51, the tapered portion 52, and the large diameter portion 53.

Although not shown, the sheath 5 may be provided with a portion having an inner diameter larger than that of the small diameter portion on the distal side of the small diameter portion. Further, the sheath 5 may have a tapered portion whose distal end coincides with the distal end of the sheath 5. In this case, the distal end of the tapered portion becomes the small diameter portion.

The small diameter portion is preferably provided at least within a predetermined range from the distal end, which is the distal opening of the sheath 5, and may be provided at least within 5.0 mm from the distal end of the sheath 5, for example. preferable. The range can be appropriately determined by the length of the conductive tip tip 1 and the desired knife length. The small diameter portion is preferably provided at a predetermined length from the distal end of the sheath 5, and is preferably 1.0 mm or more and 5.0 mm or less, for example. The length of the small diameter portion may be very small, and the lumen of the sheath 5 may have a tapered shape from the large diameter portion to the distal side of the sheath 5.

It is preferable that the size of the inner diameter of the sheath 5 is not constant in the longitudinal direction. In particular, it is preferable that the sheath 5 has a small diameter portion arranged at the distal end of the sheath 5. The inner diameter of the small diameter portion on the distal side of the sheath 5 is preferably 1.2 mm or more and 2.5 mm or less. The difference in inner diameter between the large diameter portion and the small diameter portion is preferably 0.2 mm or more and 0.4 mm or less. By providing the small diameter portion on the distal side of the sheath 5 in this way, the force required for projecting the conductive wire 2 as the snare portion from the sheath 5 does not become too large, and the tip tip 1 as the knife portion It becomes easy to stably fix the sheath 5 in a state of protruding from the sheath 5.

As shown in FIGS. 9 to 12, the sheath 5 may not be provided with a tapered portion, and the lumen of the sheath 5 may be formed so as to change in a stepped manner. In that case, one or more steps are formed in the lumen of the sheath 5 from the large diameter portion to the small diameter portion. The small diameter portion and the tapered portion may be formed by contracting the sheath tube, or may be formed by connecting tubes having different inner diameters. Also. Another member may be inserted into the tube to form a small diameter portion and a tapered portion.

When a small-diameter portion is provided in the lumen of the sheath 5, it is preferable that the surface-treated portion 7 is provided on at least a part of the small-diameter portion, and it is preferable that the surface-treated portion 7 is provided over the entire small-diameter portion. .. When a tapered portion or a medium-diameter portion is provided in the lumen of the sheath 5, it is preferable that the surface-treated portion 7 is also provided in a part or the whole of the tapered portion or the medium-diameter portion. The surface-treated portion 7 may extend to a large diameter portion. For example, as shown in FIG. 13, a surface-treated portion 7 is provided on an inner wall of a small-diameter portion of the sheath 5, which is not parallel to the major axis direction of the sheath 5, that is, a tapered portion, and a conductive connector 3 or a conductive portion 7 is provided therein. The tip tip 1 can be more firmly fixed by contacting any one or more of the sex wire 2 and the conductive tip tip 1. When a small diameter portion is provided at the distal end of the sheath 5, a portion other than the small diameter portion of the sheath 5 can be a large diameter portion. The large diameter portion may have a portion where the size of the inner diameter changes.

As shown in FIGS. 6 to 8, when the sheath 5 is not provided with a small diameter portion, the diameter of the conductive connector 3 in the direction perpendicular to the longitudinal direction of the sheath 5 and the conductivity in the direction perpendicular to the longitudinal direction of the sheath 5 Sex One or both of the diameters of the tip 1 may be larger than the inner diameter of the sheath 5. If the conductive connector 3 and / or the conductive tip 1 is formed in this way, the conductive connector 3 and the conductive tip tip are formed when a part of the conductive tip tip 1 protrudes from the sheath 5. When either or both of 1 are brought into contact with each other so as to widen the inner wall of the sheath 5, the conductive tip tip 1 is stably fixed to the tip of the sheath 5, and only the conductive tip tip 1 is projected from the sheath 5. Can be done. In this case, the diameter of the conductive connector 3 in the direction perpendicular to the longitudinal direction of the sheath 5 and / or the diameter of the conductive tip tip 1 in the direction perpendicular to the longitudinal direction of the sheath 5 is larger than the inner diameter of the sheath 5, and the diameter thereof is larger than the inner diameter of the sheath 5. The excess is preferably within 0.5 mm. The diameter of the conductive connector 3 and the diameter of the conductive tip 1 may be the same or different.

The treatment tool of the present invention is used by inserting the treatment tool into the treatment tool insertion channel of the endoscope and introducing it into the body. It is desirable that the tip tip 1 and the wire 2 are housed in the sheath 5 even when the power is not supplied, so as not to damage the inside of the treatment tool insertion channel or the lesion portion in the body.

The treatment tool is introduced to the lesion portion in the body cavity, and the handle 6 is operated to project the tip tip 1 from the tip of the sheath 5 when performing the treatment. At this time, the tip tip 1 is in a state where a part of the conductive tip tip 1, at least one of the first wire portion 2A and the second wire portion 2B, or one or more of the conductive connecting tools 3 is in contact with the inner wall of the sheath 5. The tip 1 is used as a high-frequency knife for treatment. When using a knife, a part of the conductive tip tip 1, at least one of the first wire portion 2A and the second wire portion 2B, or one or more of the conductive connectors 3 is fixed to the sheath 5, so that the tip is used. As long as no unreasonable force is applied to the tip 1, a knife-based incision, marking, or the like can be performed by operating the handle 6 during the procedure.

Further, when the treatment tool is used as a snare, the handle 6 is operated to project the conductive wire 2 from the tip of the sheath 5. Each time one or more of the conductive tip 1, the first wire portion 2A and the second wire portion 2B, and one or more of the conductive connectors 3 in contact with the inner wall of the sheath 5 protrude from the tip of the sheath 5. The pressing force for operating the handle 6 decreases. When the conductive connector 3 is made smaller than the inner diameter of the sheath 5, the wire 2 is smoothly projected after at least one of the tip tip 1, the first wire portion 2A and the second wire portion 2B protrudes from the sheath 5. be able to. In this case, since the place where the force for fixing the wire 2 to the sheath 5 acts is at least one of the conductive tip tip 1, the first wire portion 2A and the second wire portion 2B, the sheath is formed after these are projected. This is because the force for fixing the tip tip 1 to 5 is difficult to work.

Operate the handle 6 to rotate the snare loop around the lesion that needs to be squeezed, and operate the handle 6 to pull the snare to the proximal side and apply electric power to the lesion where the snare loop touches. Is cauterized. After cauterization, the snare part and the knife part are housed in the sheath 5, and the treatment tool is removed from the body.

This application claims the benefit of priority under Japanese Patent Application No. 2017-139881 filed on July 19, 2017. The entire contents of the specification of Japanese Patent Application No. 2017-139881 filed on July 19, 2017 are incorporated herein by reference.

(Example 1)
As the treatment tool of Example 1, the treatment tools shown in FIGS. 1 and 2 were produced. In the treatment tool, as the conductive tip tip 1, a stainless steel cylinder having a height of 2.2 mm, a diameter on the proximal side of 1.9 mm, and a diameter on the distal side of 0.4 mm was used. A through hole 11 having a diameter of 0.5 mm is provided on one end side of the tip tip 1. As the conductive wire 2, seven stainless steel wires having a length of 110 mm and a diameter of 0.1 mm were twisted together. As the linear object 4, five stainless steel wires having a diameter of 0.5 mm were twisted together.

The wire 2 was connected to the through hole 11 of the tip tip 1 through the wire 2. Both ends of the wire 2 were inserted from one end of a stainless steel pipe which is a conductive connector 3, the pipe was crimped, and the wire 2 was fixed to the pipe in a loop shape. A pipe having an outer diameter of 1.9 mm was used as the fitting 3. The pipe was placed proximally and the tip tip 1 was placed distal to the wire 2. Pinch the tip tip 1 and the wire 2 so that the loop area is large, 5.0 mm proximal to the distal end 21 of the wire 2 with respect to the first wire portion 2A and the second wire portion 2B of the wire 2. With the position as a base point, the wire 2 was bent so that the portion proximal to the base point extended radially outward of the sheath 5. As a result, the first bent portion 22 was formed on the first wire portion 2A, and the second bent portion 23 was formed on the second wire portion 2B. At this time, the first bent portion 22 and the second bent portion 23 were arranged facing each other in an open state of the loop.

Further, the position 1.0 mm distal to the pipe of the connector 3 with respect to the first wire portion 2A and the second wire portion 2B of the wire 2 is set as the base point so that the loop area becomes larger than the base point. The wire 2 was bent so that the distal portion extended radially outwardly of the sheath 5. As a result, the third bent portion 24 was formed on the first wire portion 2A, and the fourth bent portion 25 was formed on the second wire portion 2B. The third bent portion 24 and the fourth bent portion 25 may be formed before fixing the wire and the pipe. Then, the wire 4 was inserted from the other end of the pipe, the pipe was crimped, and the wire 2 was fixed to the distal side of the wire 4 via the pipe which is the connector 3.

As the sheath 5, a tube made of polytetrafluoroethylene having an outer diameter of 2.5 mm and an inner diameter of 1.8 mm was used. A portion 3 mm from the distal end of the sheath 5 was processed into a small diameter with an inner diameter of 1.4 mm. Further, the sheath 5 was subjected to tetra-etching treatment in a range of 5 mm from the distal end to form a surface-treated portion. The surface-treated portion has increased frictional resistance as compared with the non-treated portion, and the conductive tip tip 1 can be stably fixed by the tip of the sheath 5 as compared with the case where the surface treatment is not performed. rice field. It was confirmed that the surface-treated part turned brown and the appearance was different even under the endoscopic camera as compared with the non-treated part.

The linear object 4 was inserted from the distal side of the sheath 5, and the linear object 4 and the sheath 5 were fixed to the handle 6, respectively. By operating the handle 6, the tip tip 1 and the conductive wire 2 could be moved in and out from the tip of the sheath 5. The treatment tool was introduced into the body through an endoscope, and only the tip tip 1 was projected from the sheath 5, so that the lesion could be stably incised. In addition, the lesion portion partially incised with a knife could be squeezed with a wire 2 protruding entirely from the sheath 5, cauterized and excised.

1 Conductive tip 11 Through hole (opening)
2 Conductive wire 2A 1st wire part 2B 2nd wire part 22 1st bending part 23 2nd bending part 24 3rd bending part 25 4th bending part 3 Conductive connector 4 Linear object 5 Sheath 6 Handle 7 Sheath surface Processing part

Claims (8)

Sheath and
A linear object arranged in the sheath and
It has a first wire portion and a second wire portion extending in the perspective direction of the sheath, respectively, and the proximal end portion of the first wire portion and the proximal end portion of the second wire portion are described above. Conductive wire fixed to a linear object,
A conductive tip tip connected to the distal end of the first wire and the distal end of the second wire, respectively.
A conductive connector for connecting the linear object, the first wire portion, and the second wire portion is provided.
A part of the inner wall of the sheath has a surface-treated portion and has a surface-treated portion.
The conductive connection is such that at least the distal end of the conductive tip is located distal to the distal end of the sheath and the proximal side of the conductive tip is located inside the sheath. At least one of the tool, the first wire portion, the second wire portion, and the conductive tip tip is in contact with the surface-treated portion.
A high-frequency treatment tool for endoscopes, wherein the surface-treated portion has a higher frictional resistance than the non-treated portion. Claim 1 in which at least one of the diameter of the conductive connector in the direction perpendicular to the longitudinal direction of the sheath and the diameter of the conductive tip tip in the direction perpendicular to the longitudinal direction of the sheath is larger than the inner diameter of the sheath. The high frequency treatment tool for endoscopes described . The high-frequency treatment tool for an endoscope according to claim 1 or 2 , wherein the surface-treated portion has an appearance different from that of the non-treated portion. The high frequency for an endoscope according to any one of claims 1 to 3 , wherein the surface-treated portion is a portion subjected to one or more of a hydrophilic group-imparting treatment, an etching treatment, and a blasting treatment. Treatment tool. The high-frequency treatment tool for an endoscope according to any one of claims 1 to 4 , wherein the surface-treated portion is a portion including the distal end of the sheath. The high-frequency treatment tool for an endoscope according to any one of claims 1 to 5 , wherein the size of the inner diameter of the sheath is not constant in the longitudinal direction. From the proximal side, the sheath has a large diameter portion, a tapered portion whose inner diameter is not constant, and a small diameter portion whose inner diameter is smaller than that of the large diameter portion.
13 . The high-frequency treatment tool for endoscopes according to any one of the above. The high-frequency treatment tool for an endoscope according to claim 7 , wherein the tapered portion or the small diameter portion of the sheath is provided on the surface-treated portion.

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