JPH10234743A - High-frequency excision tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-frequency excision tool by which the extent of the loop shape and the direction of the loop for a high-frequency incision wire can be determined with a relatively simple structure, and which is excellent in operability so as to secure treatment. SOLUTION: The high-frequency excision tool 1 is provided with an operation wire 6 to the sheath 2 to be inserted into the body cavity so as to be freely advanced/retreated manner, and the end of the operation wire 6 is provided with a high-frequency incision wire 5 that is projected from the end opening of the sheath 2 and is opened in a loop shape, and that is formed in such a way that the loop is closed by drawing it through the end opening of the sheath. The sheath 2 is bifurcated and is provided with a superelastic alloy wire 7 having a bifurcated part 11 and also memorizing the opened shape, so that the part of the high-frequency incision wire 5 projected from the end opening of the sheath 2 is energized in the direction to open.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency cutting tool for cutting tissue in a body cavity using a high-frequency cutting wire.

[0002]

2. Description of the Related Art Conventionally, a high-frequency snare has been known as a high-frequency cutting tool. The high-frequency snare is used to translocate a lesion such as a polyp in the body cavity with a loop-shaped high-frequency incision wire inserted endoscopically into the body cavity, and to apply high-frequency current to the wire to cut off the lesion. . This type of high-frequency snare is disclosed, for example, in Japanese Patent Application Laid-Open No. 8-224254.

[0003]

[Problems to be solved by the invention]

(Problems of the prior art) The above-mentioned conventional high-frequency snare is such that a high-frequency incision wire is spread in a loop shape to be hung on a lesion such as a polyp. In some cases, the loop does not spread sufficiently, and it is difficult to change the direction of the loop, the operability is poor, and the treatment is sometimes difficult. Further, unless the resection target site is sufficiently raised, it is difficult to hang a high-frequency incision wire on the resection target site.

[0004] When strip biopsy is performed using a high-frequency snare, the amount of swelling at a lesion site raised with physiological saline is generally small, and the swelling of the lesion site is gentler than that of a polyp. The wire was slippery when the wire was used, and it was difficult for the high-frequency incision wire to bind the lesion site.

In order to solve such a problem, Japanese Patent Application Laid-Open No. Hei 8-224254 described above provides a pressing member for pressing against the inner surface of a body cavity at the tip of a loop formed by a high-frequency incision wire. The high-frequency incision wire is pushed in while the pressing body is brought into contact with the inner surface of the body cavity on the other side over the raised lesion and the loop shape is sufficiently widened to loop the lesion.

However, the pressing body may slip on the surface of the living body, and the loop shape of the high-frequency incision wire may not be sufficiently widened, so that the treatment may be difficult. In some cases, there is no appropriate wall for pressing the pressing body, and in this case, the loop shape cannot be sufficiently widened.

As described above, in the conventional high-frequency snare, it is difficult to determine the spread of the loop shape and the direction of the loop of the high-frequency incision wire, resulting in poor operability. (Purpose) The present invention has been made in view of the above-mentioned problem, and the purpose thereof is to easily determine the spread of the loop shape and the direction of the loop of the high-frequency incision wire while having a relatively simple configuration. An object of the present invention is to provide a high-frequency excision tool which is excellent in operability and can perform a reliable treatment.

[0008]

[Means for Solving the Problems]

(Means) The high-frequency resection tool of the present invention includes a sheath inserted into a body cavity, an operation wire member inserted and provided in the sheath so as to be able to advance and retreat, and a distal end of the sheath at a distal end of the operation wire member. From the distal end opening of the sheath by means of a reciprocating operation, which can be extended and retracted with respect to the sheath, and opened and closed in a loop shape by being retracted from the distal end opening of the sheath. A treatment section having a wire is provided, and the sheath has a crotch portion having a distal end divided into at least two branches and stored in an expanding shape, and the leg of the crotch portion protrudes from the distal end opening of the sheath. A superelastic alloy member for urging the high-frequency incision wire in a direction of expanding is inserted and provided so as to be able to advance and retreat, and each of the crotch portions of the superelastic alloy member is provided. The tip is provided with a engaging means for engaging the high-frequency incision wire.

(Operation) In this configuration, the tip of the superelastic alloy member is divided into at least two branches and engages with the incision wire, and the leg of the superelastic alloy member surely pushes and widens the loop of the high-frequency incision wire. Further, since the superelastic alloy member generally has high torsional rigidity, the high-frequency incision wire can be rotated with good followability, for example, by twisting and rotating the superelastic alloy member near the hand.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A first embodiment of the present invention will be described with reference to FIGS. (Structure) FIG. 1 schematically shows the entire structure of a high-frequency cutting tool 1 according to the first embodiment. The high-frequency resection tool 1 includes a sheath 2 made of a flexible tube, and the sheath 2 is adapted to be inserted into a body cavity of a patient, for example, endoscopically.
The sheath 2 is formed in a tubular shape from an electrically insulating material such as tetrafluoroethylene resin.
The distal end of the sheath 2 is provided with a high-frequency ablation treatment section 3 which can be protruded and retracted from the distal end opening. The opening edge of the distal end of the sheath 2 is obliquely inclined as shown in FIG. An operating section 4 for operating the treatment section 3 is provided at the proximal end of the sheath 2. The specific configuration of the operation unit 4 will be described later.

As shown in FIG. 2, the high-frequency ablation treatment section 3 has a loop-shaped high-frequency incision wire 5. The high-frequency incision wire 5 has, for example, a bending habit of expanding in an elliptical loop shape in advance. The high-frequency incision wire 5 constitutes the main body of the high-frequency ablation treatment section 3. The distal end of an operation wire 6 inserted into the sheath 2 is connected to the high-frequency incision wire 5. The operation wire 6 is made of a conductor. The high-frequency incision wire 5 is directly connected to the distal end of the operation wire 6.
And the operation wire 6 are electrically conducted. Operation wire 6
Also serves as a lead wire for conducting a high-frequency current from the high-frequency power supply to the high-frequency incision wire 5.

Further, a superelastic alloy wire 7 as a superelastic alloy member is inserted into the sheath 2. The superelastic alloy is, for example, a nickel-titanium alloy, exhibits pseudoelasticity at room temperature, and has an elastic range that is ten and several times wider than that of a normal metal. Even if it is a normal metal, even a large deformation that reaches the plastic region, the superelastic alloy is deformed in the elastic region.

As shown in FIG. 2, the distal end of the superelastic alloy wire 7 is forked by a maximum length that can protrude from the sheath 2. The forked portion 11 is subjected to heating and shape storage processing in the shape indicated by the solid line in FIG. The superelastic alloy crotch leg urges the high-frequency incision wire 5 protruding from the distal end opening of the sheath 2 in a direction to expand. The distal ends of the two distal arm portions 11a and 11b formed by the legs of the forked portion 11 are respectively engaged and fixed to the vicinity of the center of both sides of the loop portion of the high-frequency incision wire 5 by an engaging means described later. In this case, the two distal arm portions 11 of the forked portion 11
When the tips of a and 11b are fixed to the high-frequency incision wire 5, the shape of the two tip arms 11a and 11b remains in the elastic range and assumes the form shown by the dotted line in FIG. 3 (a). Tip arms 11a, 11b in forked part 11
The elastic force acts so as to open the loop shape of the high-frequency ablation treatment section 3 outward.

Two arms 11 in the forked part 11
As shown in FIG. 3B, holes 12 for passing the high-frequency incision wire 5 are formed at the distal ends of a and 11b, respectively. Further, the high-frequency incision wire 5 is fixed to the hole 12 with an adhesive 13 made of a flexible resin which is an electrical insulator. Further, the adhesive 13 is interposed between the high-frequency incision wire 5 and the superelastic alloy wire 7 to cut off the direct contact between them and electrically insulate them. Further, the surface of the superelastic alloy wire 7 is provided with an electrically insulating coating, and is electrically insulated from the operation wire 5. The operation wire 5 and the superelastic alloy wire 7 are the same sheath 2
The two members may be connected to each other with an adhesive or the like to prevent them from becoming entangled in the sheath 2.

On the other hand, the operation unit 4 is configured as shown in FIG. The operation unit 4 includes a base 16 formed by two parallel rod-shaped members, and a slider 17 slidably attached to an outer peripheral portion of the base 16.
The operation unit 4 is rotatably attached to the sheath 2. As shown in FIG. 4, the proximal end portions of the operation wire 6 and the superelastic alloy wire 7 inserted through the sheath 2 are connected and fixed to the slider 17. An electrode 18 is provided at the center of the slider 17, and the electrode 18 and the operation wire 6 are electrically connected. A high-frequency power supply (not shown) can be connected to the electrode 18. As shown in FIG. 4C, the operation wire 6 is attached by folding back its end and caulking to the electrode 18, and the folded portion 19 of the operation wire 6 is joined by brazing.

Similarly, the base end of the superelastic alloy wire 7 is folded back and fixed to a rivet 21 similarly provided on the slider 17, and the folded portion 22 is formed by a caulking ring 23.
Are joined by Note that a stopper tube 24 connected to the distal end of the operation unit 4 is fitted on the proximal portion of the sheath 2.

(Function) The treatment section 3 for high-frequency resection of the high-frequency resection tool 1 and the forked portion 11 of the superelastic alloy wire 7 move the slider 17 of the operation section 4 backward to the hand side.
It is elastically deformed and drawn into the sheath 2. Conversely, when the slider 17 is advanced to the distal end side, the high-frequency ablation treatment section 3
Is projected and released from the distal end opening of the sheath 2 and expands in a loop shape. Since the forked portion 11 at the distal end of the superelastic alloy wire 7 is shape-memory so as to open larger than the size of the loop of the incision wire 5, the loop of the incision wire 5 is greatly expanded. FIG. 2 shows a state in which both the incision wire 5 and the forked portion 11 of the superelastic alloy wire 7 protrude from the distal end opening of the sheath 2, and a state in which the loop of the incision wire 5 is maximally expanded.

The size of the loop of the incision wire 5 in the high-frequency ablation treatment section 3 depends on the amount of pushing and pulling of the slider 17 of the operation section 4 at the hand side. 5 and the amount of the superelastic alloy wire 7 can be changed by regulating the amount.

FIG. 5 shows a state in which the treatment section 3 for high-frequency ablation is applied to a polyp (affected part) 25 and is retracted partway into the sheath 2, and FIG. 5 (a) shows the state viewed from above. (B) shows a state when it is viewed from the side.

The bifurcated portion 1 of the superelastic alloy wire 7
1 is stored in a shape memory so as to open larger than the size of the loop of the high-frequency incision wire 5, so that even if the bending habit itself of the high-frequency incision wire 5 deteriorates,
As a result of the bifurcated portion 11 urging the high-frequency incision wire 5 in the expanding direction, the expansion of the loop of the high-frequency ablation treatment section 3 is sufficiently maintained. Normally, when the superelastic alloy is overheated, the stored shape is blurred and a so-called memory blur occurs. However, in this embodiment, if the high-frequency ablation treatment section 3 is retracted into the sheath 2, the superelastic alloy wire 7 is forked. Since the portion 11 is completely drawn into the sheath 2, only the tip of the high-frequency incision wire 5 protruding from the sheath 2 generates heat even when high-frequency power is supplied, and the superelastic alloy wire 7 is not overheated. Therefore, the so-called memory blur of the superelastic alloy wire 7 can be prevented.

During the operation, there are times when it is desired to change the direction of the high-frequency ablation treatment section 3 around the axis. In this case, the operation unit 4 on the hand side is rotated with respect to the sheath 2. Then, the slider 17 also rotates together with the operation unit 4 and twists the superelastic alloy wire 7 fixed to the slider 17. As described above, the superelastic alloy wire 7 has good torque transmission, so that the forked portion 11 at the tip is twisted with good followability, and the high-frequency ablation treatment section 3 can be positively rotated. Thereby, the direction of the loop of the treatment section 3 for high frequency resection can be easily adjusted only by rotating the operation section 4, and the treatment is easy even in a narrow body cavity.

(Effect) According to the first embodiment, when the treatment section 3 is protruded from the distal end opening of the sheath 2, the forked portion 11 at the distal end of the superelastic alloy wire 7 is connected to the high-frequency incision wire 5. Since the loop shape acts to open outward, the loop of the high-frequency incision wire is greatly expanded, and the high-frequency incision wire 5 can reliably obtain a large-opening loop shape. The superelastic alloy wire 7 is the operation wire 5
Since it is electrically insulated from electricity, there is no heat generation due to energization, and so-called memory blur is unlikely to occur. The effect of greatly expanding the loop of the high-frequency incision wire 5 is maintained for a long time. In addition, the high-frequency ablation treatment section 3 can be rotated with good followability by an operation on the hand side. Therefore, high-frequency ablation with good operability can be performed.

(Modification of First Embodiment) FIGS. 6A and 6B show different modifications of the first embodiment. In each of the figures, the sheath 2 is not shown, and only the relationship between the operation wire 6 and the superelastic alloy wire 7 is shown.

FIG. 6A shows a structure in which the superelastic alloy wire 7 is formed in a tube shape, and the operation wire 6 is inserted into the hollow portion of the superelastic alloy wire 7. FIG.
(B) shows the superelastic alloy wire 7 as only the tip portion. Although the torsional transmission is not improved, it is effective for expanding the loop shape, and the amount of the superelastic alloy is small, which is economical. In FIG. 6C, the operation wire 6 is used only at the tip. The superelastic alloy wire 7 is not provided with an insulating coating, but is made to conduct a high-frequency current therethrough. According to this, the torsion transmission property of transmitting the rotational operation force on the hand side to the distal end by the superelastic alloy wire 7 is improved. The engagement between the incision wire 5 and the forked portion 11 of the superelastic alloy wire 7 is performed by fixing by brazing with conductive brazing.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIGS. (Configuration) The basic configuration of the second embodiment is the same as that of the first embodiment. Also in the second embodiment, the shape of the forked portion 11 at the tip of the superelastic alloy wire 7 is stored so that the loop shape of the high-frequency incision wire 5 is expanded as shown in FIG. As shown in FIG. 8, the forked part 11 stores the shape of the loop of the high-frequency incision wire 5 such that the loop surface is curved.

Furthermore, the tip of the forked portion 11 of the high-frequency incision wire 5 and the superelastic alloy wire 7 is not fixed,
A hole 12 is provided at the tip of the forked portion 11 so that the high-frequency incision wire 5 can be inserted therethrough.

The operation section 4 is provided with a first slider 17a to which only the operation wire 6 is connected and a second slider 17b to which only the superelastic alloy wire 7 is connected. 4 is slidably provided in the front-rear direction with respect to the base 16. The electrode 18 is provided only on the first slider 17a to which the operation wire 6 is connected. FIG. 9 shows a state in which the first slider 17a and the second slider 17b of the operation unit 5 are viewed from the back side. Second
The slider 17b is provided with a one-sided stopper 31 extending to the first slider 17a. Stopper 3
1 is provided with a slit 32 along the sliding direction.

A stopper screw 33 is provided on the first slider 17a, and a shaft portion of the stopper screw 33 is fitted into and engaged with the slit 32 of the stopper 31, and is slidably linked. When the stopper screw 33 is screwed in and tightened, the first slider 17a
And the second slider 17b is fixed in relative position.

(Operation) In the configuration of this embodiment, the treatment section 3 for high-frequency ablation and the superelastic alloy wire 7 can advance and retreat independently of the sheath 2, respectively. Can be arbitrarily changed. Each operation of the high-frequency ablation treatment section 3 and the superelastic alloy wire 7 is individually performed by the first slider 17a and the second slider 17b of the operation section.

The projecting amount of the high-frequency ablation treatment section 3 is adjusted by moving the operation wire 6 forward and backward by the first slider 17a. Further, the position of the superelastic alloy wire 7 with respect to the high-frequency incision wire 5 is adjusted by moving the second slider 17b. After these positions are adjusted, the stopper screw 33 provided on the slider 17a is tightened to fix both the first slider 17a and the second slider 17b. by this,
The positional relationship between the treatment section 3 and the forked section 11 is fixed. After being fixed, both sliders 17a and 17b can be slid together only by operating at least one of the sliders 17a and 17b.

By adjusting the positions of the treatment section 3 and the fork part 11 in this manner, it is possible to adjust the amount of bending of the loop of the incision wire 5 and the amount of expansion of the loop.
That is, for the incision wire 5 in the treatment section 3,
Since the position at which the distal ends of the distal arm portions 11a and 11b of the forked portion 11 are locked is changed, the amount by which the forked portion 11 of the distal end of the superelastic alloy wire 7 expands the incision wire 5 in a loop shape and the amount The amount by which the incision wire 5 is bent changes.

After the high-frequency incision wire 5 is applied to a target site such as a living body polyp, the second slider 17b
By retracting only the superelastic alloy wire 7, only the superelastic alloy wire 7 can be pulled into the sheath 2 and retracted so as not to hinder the operation of the high-frequency ablation procedure.

Next, FIG. 10 shows an example of the operation when the projecting amount of the superelastic alloy wire 7 is changed without changing the position of the high-frequency incision wire 5 with respect to the sheath 2. FIG. 10 is a view of the distal end portion of the high-frequency cutting tool 1 as viewed from the side. When the bifurcated portion 11 of the superelastic alloy wire 7 is not protruded with the loop portion of the treatment section 3 protruding from the sheath 2, the incision wire 5 hardly bends as shown in FIG. When the amount of protrusion of the forked portion 11 is increased by operating the superelastic alloy wire 7, as shown in FIGS. 10 (b), 10 (c), and 10 (d), according to the amount of protrusion, The bending amount of the loop portion of the incision wire 5 gradually increases.

(Effect) In this embodiment, since the treatment section 3 for high-frequency ablation can be curved, access to the wall surface of the living body is facilitated. In addition, since the positions of the incision wire 5 and the forked portion 11 can be adjusted, the bending angle of the loop of the treatment section 3 and the degree of the loop expansion can be adjusted.
Therefore, the operability can be improved, and the reliability of the treatment can be improved.

(Modification of the Second Embodiment) The means for fixing the two sliders 17a and 17b does not need to be related to the slit 32 provided in the stopper 31 and the stopper screw 33, and may use another locking mechanism or, for example, a ratchet. It may be a mechanism or the like.

(Third Embodiment) A third embodiment of the present invention will be described with reference to FIG. (Construction) This third embodiment is different from the second embodiment described above in that the bifurcated portion 1 at the tip of the superelastic alloy wire 7 is used.
1, a slit 41 which is partially open is formed on the periphery of the hole 12 through which the high-frequency incision wire 5 passes.
1, the incision wire 5 can be detached from the forked portion 11. Specifically, examples shown in the respective drawings of FIG. 11 can be considered.

FIG. 11 (a) shows a hole 12 of the above-described second embodiment in which a notch is provided. FIG.
In FIG. 1 (b), the distal ends of the two arms 11a and 11b in the forked portion 11 are further made into a forked shape, and the incision wire 5 is hooked between the forked portions from the inside of the loop. . The one shown in FIG. 11 (c) is formed so that the tip of the forked portion of the hole 12 shown in FIG. 11 (b) is elastically closed. FIG. 11D shows an example in which the hole 12 shown in FIG. 11A is formed to be elongated, and the split portion 41 is shifted from the engagement position of the cutting wire 5 passing through the hole 12.

(Function) In the third embodiment, the engaging means between the high-frequency incision wire 5 and the superelastic alloy wire 7 is the engagement means between the high-frequency incision wire 5 and the forked portion 11 of the superelastic alloy wire 7. Is removable. At the time of treatment, as in the second embodiment, the forked portion 11 expands the loop of the incision wire 5 and curves the loop, and applies the incision wire to the target while maintaining the appropriate loop shape. After the incision wire 5 is applied, the incision wire 5 and the superelastic alloy wire 7
To the hand side to tighten the loop. Incision wire 5
Since the super elastic alloy wire 7 is not necessary after binding the target portion, the engaging portion at the tip of the super elastic alloy wire is disengaged by strongly pulling only the super elastic alloy wire (second slider), Only the incision wire 5 remains at the distal end. Thereafter, the affected part can be incised by passing a high-frequency current. At this time, since the superelastic alloy wire 7 has been removed, there is no influence from high-frequency current or heat.

(Effect) In this embodiment, the superelastic alloy wire 7 can be removed from the high-frequency incision wire 5. 11 (b) and 11 (c) can support the loop of the high-frequency incision wire 5 outward, while
It can be easily removed by pulling the superelastic alloy wire 7. By removing the super-elastic alloy wire 7 from the high-frequency incision wire 5, the super-elastic alloy wire 7 is not affected by high-frequency current or heat, and its shape lasts longer. Further, since the superelastic alloy wire 7 is detachable, it can be easily combined with the existing high-frequency excision tool 1 and can be economical.

[Appendix] According to the above description, at least the following items can be obtained. 1. A sheath inserted into the body cavity, an operation wire member inserted into the sheath so as to be able to advance and retreat, and a tip provided at the tip of the operation wire member, which can protrude from the tip of the sheath and can advance and retreat with respect to the sheath. A treatment section having a high-frequency incision wire formed so as to protrude from the distal end opening of the sheath by a reciprocating operation, open in a loop shape, and retract from the distal end opening of the sheath to close the loop; It has a crotch portion that is freely inserted and has a shape that has a tip that is split into at least two branches and expands, and a portion of the high-frequency incision wire that protrudes from a tip opening of the sheath by a leg of the crotch portion. A superelastic alloy member that urges in a direction of expanding, and a tip of each leg of a crotch portion of the superelastic alloy member is engaged with the high-frequency incision wire. RF cutter, characterized by comprising an engagement means. 2. The high frequency cutting tool according to claim 1, wherein the crotch portion of the superelastic alloy member is also stored in a shape for urging the crotch portion in a direction to bend the loop surface of the incision wire. According to the supplementary item 2, there is a sufficient wire loop spread despite the simple structure,
In addition, the wire loop can be bent, and the degree of expansion and the bending angle of the incision wire can be adjusted by the amount of protrusion of the superelastic alloy wire member from the sheath. The operability is good, the wall of the affected part of the living body can be easily accessed, and the treatment can be performed reliably.

3. The high frequency cutting tool according to claim 1, wherein the operation wire member and the treatment section are made of stainless steel. 4. 2. The high frequency cutting tool according to claim 1, wherein the engaging means allows the crotch portion of the superelastic alloy member to slide freely with respect to the cutting wire. 5. The high frequency cutting tool according to claim 1, wherein the engaging means fixes a crotch portion of the superelastic alloy member to the cutting wire. 6. The high frequency cutting tool according to claim 1, wherein the engaging means is capable of removing a crotch portion of the superelastic alloy member with respect to the cutting wire.

[0042]

As described above, according to the present invention, the spread of the loop shape and the direction of the loop of the high-frequency incision wire can be easily determined with a relatively simple structure, and the operability is excellent and a reliable treatment can be performed. It can be carried out.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing an entire configuration of a high-frequency cutting tool according to a first embodiment.

FIG. 2 is a cross-sectional view of the configuration of the treatment section of the high-frequency resection tool according to the first embodiment as viewed from above.

FIG. 3A is an explanatory view of a tip portion of a superelastic alloy wire of the high-frequency cutting tool according to the first embodiment, and FIG. 3B is a view of an engaging portion of the high-frequency incision wire and the superelastic alloy wire. Perspective view.

FIG. 4A is a rear view of the high-frequency resection tool according to the first embodiment, FIG. 4B is an arrow view of a portion along line BB in FIG. 4A, and FIG. The arrow view of the part which follows the middle CC line.

FIG. 5 is an operation explanatory view of the treatment unit for high frequency resection when the high frequency resection tool according to the first embodiment is used.

FIGS. 6A, 6B, and 6C are explanatory views showing different modifications of the high-frequency incision wire and the superelastic alloy wire of the first embodiment, respectively.

FIG. 7A is a cross-sectional view of the configuration of the treatment section of the high-frequency resection tool according to the second embodiment as viewed from above, and FIG. 7B is an engagement section between the high-frequency incision wire and the superelastic alloy wire. FIG.

FIG. 8 is an operation explanatory view of a treatment section for high frequency resection when the high frequency resection tool according to the second embodiment is used.

FIG. 9 is a plan view of an operation unit of the high-frequency cutting tool according to the second embodiment.

FIG. 10 is a view for explaining the operation of the treatment section of the high-frequency resection tool 1.

FIGS. 11 (a), (b), (c), and (d) are perspective views respectively showing the configuration of a treatment section of a high-frequency resection tool according to a third embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... High frequency cutting tool, 2 ... sheath, 3 ... treatment part, 4 ... operation part, 5 ... high frequency incision wire, 6 ... operation wire, 7 ... super elastic alloy wire, 11 ... bifurcated part, 11a, 11b ... arm part , 12 ... holes.

Claims (1)

[Claims] A sheath inserted into a body cavity; an operating wire member inserted into the sheath so as to be able to advance and retreat; and a distal end of the operating wire member, which is protrudable from the distal end of the sheath and is connected to the sheath. A treatment unit having a high-frequency incision wire that is movable forward and backward and protrudes from the distal end opening of the sheath by a retracting operation, opens in a loop shape, and is drawn in from the distal end opening of the sheath to close the loop; A high-frequency incision protruding from a distal end opening of the sheath by a leg of the crotch portion which is inserted into the sheath so as to be able to advance and retreat, and has a distal end divided into at least two forks and stored in a shape that expands; A super-elastic alloy member that urges a portion of the wire for expanding, a tip of each leg of the crotch portion of the super-elastic alloy member for the high-frequency incision. RF cutter, characterized by comprising an engaging means for engaging the ear.