JPH0544295B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to endoscopic treatment tools such as biopsy forceps and grasping forceps.

[Technical background of the invention and its problems]

An endoscopic treatment tool, such as a biopsy forceps, has a pair of biopsy cups at the tip of a flexible sheath.
This biopsy cup is opened and closed by pushing and pulling a wire inserted into the sheath (Japanese Patent Laid-Open No. 59-202576).

However, the above-mentioned operating wire is constructed by twisting a large number of stainless steel wires into a single rope shape. There are cases where one wire is used as it is over the entire length, and cases where the same wire is connected in the middle and used as a single wire.

However, since the twisting direction is the same over the entire length of the operating wire, when the operating wire is strongly pulled, a force is generated that tends to rotate the operating wire in the direction in which the twist returns. This rotational force is then transmitted to the opening/closing operation member of the biopsy cup, twisting the opening/closing operation member, and increasing the sliding resistance due to the movement. Therefore, sufficient actuation force cannot be transmitted to the biopsy cup. The same applies when pushing in the operating wire and closing the biopsy cup.

[Purpose of the invention]

The present invention has been made focusing on the above circumstances,
The purpose is to provide an endoscopic treatment instrument in which even if force is applied to the twisted operation wires, no rotational force is generated in the operation wires themselves, and the distal treatment section can operate smoothly and reliably. There is a particular thing.

[Summary of the invention]

The present invention is an endoscopic treatment instrument in which the operation wire for operating the treatment section is constructed by connecting at least two or more wire portions with mutually different twist directions.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described based on the drawings.

This embodiment is an endoscopic biopsy forceps. This biopsy forceps includes a sheath 1, an operation section 2, and a tip treatment section 3.
It is composed of. The operating section 2 is attached to the proximal end of the sheath 1, and the distal treatment section 3 is attached to the distal end of the sheath 1. The distal treatment section 3 includes a pair of biopsy cups 4, 4 which are pivotally connected to a shaft pin 5, and the biopsy cups 4, 4 are opened and closed via a link mechanism 6 by an operating wire 7, which will be described later. The operating wire 7 is guided to the operating section 2 through the sheath 1 and connected to the slider 8 of the operating section 2. Then, by placing the thumb on the finger ring 10 provided on the main body 9 of the operation section 2 and placing the index finger and middle finger of the same hand on the slider 8 and moving the slider 8, the operation wire 7 can be pushed and pulled. There is.

On the other hand, the sheath 1 is made of a tightly wound coil.
Furthermore, this tightly wound coil has a coil part 1 on the tip side.
1 and a coil portion 12 on the rear end side, and both coil portions 11 and 12 are connected via a connecting tube 13. In addition, each coil part 11, 12 is made of stainless steel wire of the same thickness wound closely,
Its winding direction is opposite. Each coil part 11,1
The lengths of the two are the same.

Further, as shown in FIG. 2, the operating wire 7 is divided into a wire portion 13 at the tip side and a wire portion 14 at the rear end, and each wire portion 13, 14 is connected to the connecting tube 1.
5. Each of these wire portions 13 and 14 is connected to one wire as shown in FIG.
Book core strand 16 and multiple side strands 1
7,..., but the twist directions are opposite to each other. In other words, the winding directions of the side strands 17, . . . are reversed as shown in FIG.
In addition, each of the above-mentioned strands 16, 17, ... is composed of a large number of stainless steel wire strands 18,
The core strand 16 and the side strands 17, . . . are twisted in opposite directions.
Therefore, the twist direction of each wire section 13, 14 means its overall characteristics, and if the direction of rotation of the wire sections 13, 14 is opposite when the same external force is applied, the twist direction is opposite. Suppose that

Further, each of the wire portions 13 and 14 is the same except for the direction in which the wires are twisted, and the length thereof is also the same.

As shown in FIG. 2, a tip operating member 21 is attached to the tip of the operating wire 7, and is pivotally connected to the links 23, 23 of the link mechanism 6 via a pin 22. There is. The other ends of the links 23, 23 are pivotally connected to the proximal ends of the biopsy cups 4, 4 via further pins 24, 24.

When using the biopsy forceps, the tip treatment section 3 and sheath 1 are introduced into the body cavity through the insertion channel of the endoscope, and the biopsy forceps are operated under observation using the endoscope. . That is, when opening the biopsy cups 4, 4, the slider 7 is pushed into the main body 8. Further, when closing the biopsy cups 4, 4, the slider 7 is pulled toward the proximal side with respect to the main body 8. At this time, each member of the distal treatment section 3 is pulled toward the operating section 2 via the operating wire 7, so that a compressive force is applied to the sheath 1, and a tensile force is applied to the operating wire 7.
First, the compressive force applied to the sheath 1 is applied to each of the coil parts 11 and 12, and in the winding direction shown in FIG. The portion 12 rotates to the left. Moreover, since the lengths of each coil portion 11 and 12 are the same, the same amount of rotation occurs even if the rotation direction is reversed. Therefore, these rotations cancel each other out, and no rotation of the sheath 1 as a whole occurs. In other words, no rotation is transmitted to the distal treatment section 3.

Although a tensile force is applied to the sheath 1 when the biopsy cup 4 is opened, the distal treatment section 3 does not rotate at this time due to the same action as described above.

Therefore, it is easy to aim at the region to be treated, and the targeted region can be treated accurately.

On the other hand, in the wire portions 13 and 14 of the operating wire 7 to which the tensile force is applied, a rotational force in the direction of untwisting is generated depending on the twisting direction. In particular, biopsy cup 4,
4, the stronger the force you pull to tear apart the living tissue, the greater the rotational force generated. However, since the twist directions of the wire portions 13 and 14 are opposite to each other, their rotations cancel each other out near the connecting tube 15. Therefore, it is not transmitted to the distal end operation member 21 of the distal treatment section 3 and the link mechanism 6. Therefore, the biopsy cups 4, 4 can be operated smoothly and reliably without twisting these pivot points or increasing their sliding resistance.

By the way, in the above embodiment, each coil portion 11, 1
Although the diameters and overall lengths of the two strands are the same, even if they are not completely the same, rotation of the distal treatment section 3 can be prevented quite sufficiently.

In addition, the coil portion 11 on the tip side is made of a thin wire,
The coil portion 12 on the rear end side is made of a thick wire, and the total length of the coil portion 11 on the front end side is made shorter than the total length of the coil portion 12 on the rear end side, so that each coil portion 11, 12 is resistant to compressive force and tensile force. The rotations may be the same. According to this embodiment, the coil portion 11 on the distal end side can be made softer. Therefore, for example, the resistance when passing through the curved portion of the endoscope can be reduced.

Moreover, at least one of each coil portion 11, 12 may be wound with two or more threads.

Further, the number of coil portions is not limited to two, but may be three or more.

On the other hand, the wire portion 13 on the tip side of the operation wire 7 is made shorter in length than the wire portion 14 on the rear end side, and furthermore, the stainless steel wire 1
8,... may be made thinner and the number of twists may be increased.
According to this, although the twisting caused by the tensile force is not completely eliminated, the wire portion 13 can be made softer, and the opening and closing operation when the wire portion 13 is passed through the curved portion of the endoscope becomes smooth.

In addition, when the operating wire 7 is composed of the core strand 16 and the side strands 17, . . . as in the above embodiment, the direction of twisting only the side strands 17, . In this case, the connecting tube 15 is unnecessary, and the diameter can be made smaller accordingly. Further, instead of the operating wire consisting of a core strand and side strands, it may be a wire simply twisted together.

Furthermore, the present invention is not limited to the case of biopsy forceps, but can be similarly applied to treatment instruments such as grasping forceps.

〔Effect of the invention〕

As described above, according to the present invention, even if force is applied to the operating wire when the operating wire is operated, the rotational force is not transmitted to the operating portion of the treatment section at the distal end.
Therefore, the operating force is sufficiently transmitted to the treatment section, allowing reliable and smooth operation.

[Brief explanation of the drawing]

FIG. 1 is a side view of an endoscopic treatment instrument showing an embodiment of the present invention, FIG. 2 is a side sectional view of the distal end thereof, and FIG. 3 is a longitudinal sectional view of the wire portion thereof. DESCRIPTION OF SYMBOLS 1... Sheath, 3... Tip treatment part, 7... Operation wire, 11, 12... Coil part.

Claims (1)

[Claims] 1. In an endoscopic treatment instrument in which a twisted operation wire is passed through a sheath with a treatment section attached to the tip, and the treatment section is operated by this operation, at least two wires are twisted in different directions. The above-mentioned wire parts are connected to form a single operating wire, and rotations generated when force is applied to the operating wire are canceled out due to the different twist directions of the wire parts. Endoscopy treatment equipment.