JP2000083964A - Wire loop type treatment implement for endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the safe use of a wire loop without the occurrence of a change in such manipulation resistance as to give rise to an illusion by providing a wire loop type treatment implement with bent parts formed on both sides across the front end of the wire loop to a positional relation with which the wire loop is not put into and out of the inside of the front end of a flexible sheath at the time of putting into and out of this sheath. SOLUTION: The wire loop 3 is formed to a shape approximate to a slender hexagonal shape. The wire loop is bent outward in an outward bent part 3b adjacent to the front end bent part 3a, is bent inward to some extent in the next intermediate bent part 3c and is bent toward a rear connecting pipe 4 at the rear side bent part 3d. The wire loop is then formed to a shape approximately line symmetrical with a line connecting the front end unbent part 3a and the connecting pipe 4 as a diagonal axis and is formed to a shape slightly distorted as compared with the exact line symmetrically shaped so as to prevent the paired bent parts (outward bent parts 3b, 3b, the intermediate bent parts 3c, 3c and the rear side bent parts 3d, 3d) from being simultaneously put into and out of the inside of the front end in the flexible sheath 1 when a manipulation wire 2 is pulled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wire loop type treatment device for an endoscope such as a high-frequency snare for an endoscope or a basket type foreign matter collection device.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a conventional high-frequency snare for an endoscope. An operation wire 2 is inserted through a flexible sheath 1 so as to be able to advance and retreat in the axial direction. Is connected to a wire loop 3 formed by bending an elastic wire into, for example, a substantially hexagonal shape.

[0003] The wire loop 3 is formed by bending an elastic wire back into a U-shape and having the bent back portion 3a as a tip. The wire loop 3 is provided near the bent back portion 3a of the pair of elastic wires. The direction bending part 3b is formed.

Such an endoscope snare operates a wire loop 3 by operating the operating wire 2 in the axial direction.
Goes into and out of the distal end of the flexible sheath 1, and the wire loop 3 expands in a loop shape by its own elasticity outside the flexible sheath 1, and contracts by being drawn into the flexible sheath 1.

[0005]

FIGS. 6 and 7 show that the operation wire 2 of the above-described endoscope snare is pulled toward the hand side, and the wire loop 3 is drawn into the distal end of the flexible sheath 1. FIG. The resistance is very large at the moment when the bent portion 3c of the wire loop 3 is pulled into the distal end of the flexible sheath 1 as shown in FIG.
As shown in FIG. 7, when the bent portion 3c enters the flexible sheath 1, the resistance is reduced.

In such an operation, in a conventional endoscope snare, since the wire loop 3 is formed symmetrically, a pair of (ie, two) bent portions 3c, 3c are simultaneously made of a flexible sheath. Get in and out of the tip of 1.

Therefore, the bent portion 3 of the wire loop 3
Immediately before c is drawn into the distal end of the flexible sheath 1,
The resistance of the pair of bent portions 3c, 3c is simultaneously applied, and the repulsive force generated in the two bent portions 3c, 3c is also applied, so that the amount of pulling operation force of the operation wire 2 becomes very heavy. You will feel.

Then, the operator illusions that the polyp is "tightened", energizes the high-frequency current, causes bleeding due to insufficient cauterization, or illusions that the polyp has been cut. May end the procedure.

As shown in FIG. 8, when the operation wire 2 is narrowed and a pair of outward bent portions 3b, 3b adjacent to the bent back portion 3a collide with each other, the operation wire is moved from that position. Since the amount of the pulling operation force of No. 2 suddenly increases, the operator may have the same illusion as described above.

Accordingly, the present invention provides a safe and correct operation that does not cause a change in operation resistance that may cause an illusion to the operator when the operation wire is pulled and the wire loop is pulled into the distal end of the flexible sheath. An object of the present invention is to provide a wire loop type treatment instrument for an endoscope that can be used.

[0011]

In order to achieve the above object, a wire loop type treatment instrument for an endoscope according to the present invention has an operation wire inserted and arranged so as to be able to advance and retreat axially in a flexible sheath. A wire loop formed of an elastic wire is provided at the distal end of the operating wire, and the operating wire is advanced and retracted in the axial direction so that the wire loop enters and exits the distal end of the flexible sheath, and the wire loop Is formed in a wire loop type treatment instrument for an endoscope, which is expanded in a loop shape by its own elasticity outside the flexible sheath and contracted by being drawn into the flexible sheath. The bent portions formed on both sides of the elastic wire with the distal end of the wire loop interposed therebetween are used when the wire loop enters and exits the distal end of the flexible sheath. Characterized by providing a positional relationship not out of the.

The wire loop may be formed in a polygonal shape, and the wire loop is formed by bending an elastic wire back into a U-shape and having the bent back portion as a tip. A pair of outwardly bent portions may be formed at asymmetric positions near the bent-back portion.

[0013]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a distal end portion of a wire loop type treatment instrument for an endoscope according to a first embodiment of the present invention,
Reference numeral 1 denotes a flexible sheath made of, for example, a tube made of tetrafluoroethylene resin, which is inserted into and removed from a treatment tool insertion channel of an endoscope (not shown).

In the flexible sheath 1, a conductive operation wire 2 made of, for example, a stranded wire made of stainless steel is inserted and disposed so as to be able to advance and retreat in the axial direction.
A wire loop 3 is connected to the end of the cable via a connection pipe 4. However, the operation wire 2 and the wire loop 3 may be directly connected. The operation wire 2 includes a flexible sheath 1
Is operated at an operation unit (not shown) connected to the base end.

The wire loop 3 is formed in such a shape that a single conductive elastic wire is bent back at an intermediate point, and that portion is used as a tip bent back portion 3a of the wire loop 3, and no external force is applied. In the state, a loop extending several centimeters is formed.

As the elastic wire, for example, the diameter is 0.2
A stranded wire or a single wire made of stainless steel of about 0.5 mm is used, and the wire loop 3 can elastically deform the elastic wire by applying an external force to narrow the wire, but if the external force is removed, Then, the loop returns to the original loop shape due to the elasticity of the elastic wire.

In this embodiment, the wire loop 3 is formed in a shape close to an elongated hexagon, and the outward bent portion 3 formed adjacent to the tip bent back portion 3a is formed.
b, outwardly bent at the next intermediate bent portion 3c to a certain extent, and rearward bent portion 3d
Is bent toward the rear connecting pipe 4.

Although the wire loop 3 is formed in a shape close to line symmetry with a line connecting the tip bent back portion 3a and the connecting pipe 4 as a symmetric axis, the wire loop 3 has a slightly distorted shape as compared with an accurate line symmetry shape. When the operation wire 2 is pulled, a pair of bent portions (ie, a pair of outward bent portions 3b, 3b, and a pair of intermediate bent portions 3c, 3) are formed.
c, and the pair of rear bent portions 3d, 3d) are prevented from entering and leaving the distal end of the flexible sheath 1 at the same time.

Specifically, a pair of rear bent portions 3d,
A distance L2 between one of the rear bent portions 3d and the connecting pipe 4 is longer than a distance L1 between the other rear bent portion 3d and the connecting pipe 4 (L2> L1). . Therefore, the pair of rear bent portions 3d, 3
d does not move in and out of the distal end of the flexible sheath 1 at the same time.

The distances L3, L4 between the pair of intermediate bent portions 3c, 3c and the rear bent portions 3d, 3d are the same on both sides (L3 = L4). Therefore, the pair of intermediate bent portions 3c, 3c is also a flexible sheath 1
Do not come and go at the tip of

FIG. 2 shows a state in which the operation wire 2 is pulled from the near side and the intermediate bent portions 3c, 3c are approaching the mouth of the flexible sheath 1, and one intermediate bent portion 3c and the other intermediate bent portion 3c. The bent portion 3c and the flexible sheath 1
Are sequentially drawn into the tip of the camera at a shifted timing.

Accordingly, when each intermediate bent portion 3c passes through the mouth of the flexible sheath 1, the resistance increases and the amount of pull-in operation force increases, but the degree is small and the operator may have an illusion. There is no.

Returning to FIG. 1, a pair of outwardly bent portions 3b, 3b adjacent to the tip bent back portion 3a are formed at asymmetric positions. Therefore, the shape of the tip bent-back portion 3a is closer to a J-shape than a U-shape when viewed in a range up to the outward bent portion 3b.

As a result, when the operation wire 2 is pulled and the wire loop 3 is narrowed, as shown in FIG. 3, even if the pair of outwardly bent portions 3b, 3b approach each other, they do not come into contact with each other. In addition, there is no change in the amount of operation force that causes an illusion to the operator.

The present invention is not limited to the above embodiment. For example, the bending position of the wire loop 3 does not go in and out of the flexible sheath 1 at the same time as the wire loop 3 goes in and out. Any setting may be made as long as it is a positional relationship.

As shown in FIG. 4, the present invention may be applied only to the outwardly bent portions 3b, 3b adjacent to the bent back portion 3a of the wire loop 3 formed in a curved shape. Further, the present invention may be applied to a so-called basket-type foreign substance collection tool for an endoscope in which the wire loop 3 is formed in a cage shape using three or more elastic wires.

[0027]

According to the present invention, the bent portions formed on both sides of the distal end of the wire loop are provided in a positional relationship such that the bent portions do not enter and exit simultaneously when the wire loop enters and exits the distal end of the flexible sheath. Thus, when the operation wire is pulled and the wire loop is pulled into the distal end of the flexible sheath, a large change in operation resistance that causes an illusion to the operator does not occur. The type treatment instrument can be used correctly and safely.

[Brief description of the drawings]

FIG. 1 is a plan sectional view of a distal end portion of a wire loop type treatment instrument for an endoscope according to a first embodiment of the present invention in a state where a wire loop is widened.

FIG. 2 is a plan sectional view of a distal end portion of the wire loop-type treatment instrument for an endoscope according to the first embodiment of the present invention in a state where a wire loop is being narrowed.

FIG. 3 is an enlarged plan view of a distal end portion of the wire loop when the wire loop of the wire loop treatment device for an endoscope according to the first embodiment of the present invention is narrowed.

FIG. 4 is a plan cross-sectional view of a distal end portion of a wire loop type treatment instrument for an endoscope according to a second embodiment of the present invention in a state where a wire loop is widened.

FIG. 5 is a plan sectional view of a distal end portion of a conventional endoscope wire loop-type treatment instrument in a state where a wire loop is widened.

FIG. 6 is a plan sectional view of a distal end portion of a conventional endoscope wire loop-type treatment instrument in a state where a wire loop is being narrowed.

FIG. 7 is a plan sectional view of a distal end portion of a conventional wire loop-type treatment instrument for an endoscope in a state where a wire loop is narrowed.

FIG. 8 is an enlarged plan view of a distal end portion of a wire loop of a conventional wire loop-type treatment instrument for an endoscope when the wire loop is narrowed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flexible sheath 2 Operation wire 3 Wire loop 3a Tip bending back part 3b, 3c, 3d Bending part

Claims (3)

[Claims] An operation wire is inserted through a flexible sheath so as to be able to advance and retreat in an axial direction, a wire loop formed by an elastic wire is provided at a tip of the operation wire, and the operation wire is advanced and retracted in an axial direction. By operation, the wire loop moves in and out of the distal end of the flexible sheath, and the wire loop expands in a loop shape by its own elasticity outside the flexible sheath, and is drawn into the flexible sheath. The wire loop treatment device for an endoscope, wherein the bending portion formed on both sides of the distal end of the wire loop of the elastic wire forming the wire loop is formed by the wire loop. A wire loop treatment device for an endoscope, wherein the treatment device is provided in a positional relationship such that it does not simultaneously enter and exit the distal end of the flexible sheath. 2. The endoscope wire loop treatment tool according to claim 1, wherein the wire loop is formed in a polygonal shape. 3. The wire loop is formed by bending an elastic wire back into a U-shape and having the bent back portion as a tip, and a pair of outwardly positioned asymmetric positions near the bent back portion. 3. The wire loop treatment device for an endoscope according to claim 1, wherein a bent portion is formed.