JP7016252B2 - Basket-type endoscope treatment tool - Google Patents

Description

The present invention relates to a basket-type endoscopic treatment tool that is inserted into a body cavity and has a treatment portion for sandwiching and crushing a foreign substance such as a stone in the body cavity by a basket made of a plurality of elastic wires, and is particularly difficult to fit. The present invention relates to a basket-type endoscopic treatment tool capable of easily releasing the incarcerated body even when the incarcerated body is incarcerated.

Generally, for collecting and crushing foreign substances such as stones in the body cavity, a basket-type endoscope treatment tool having a basket portion that can be recessed from a long flexible sheath and can be expanded and contracted like a basket is used. Will be done. This basket-type endoscope treatment tool is inserted into the endoscope channel with the basket portion housed in the flexible sheath and brought close to foreign substances such as stones in the body cavity, and the basket is placed from the tip of the flexible sheath. By projecting the portion, stones and the like are taken into the basket portion, and the operation wire connected to the basket portion is pulled to contract the basket portion and crush or grip the stones and the like to pull them out.

When gripping a calculus in this way, if the size of the gripped foreign matter is too large or too hard, it may be possible to collect and open the foreign matter, and this state is called incarceration.
Therefore, in the case of incarceration, the basket wire is configured to be detached from the tip tip that gathers the tips of the basket wires constituting the basket portion, so that the incarceration is released and the basket-type endoscope treatment tool is used. A technique for facilitating removal from the body is known (see Patent Document 1).

Special Table 2004-516880 Gazette

However, although the basket-type endoscope treatment tool described in Patent Document 1 can be released from incarceration, the tip tip remains in the patient's body after the tip of the basket wire is removed from the tip tip. It ends up. Therefore, it is necessary to separately perform other measures for collecting the tip, which has a problem of further burdening the patient's body.

In view of such a problem, an object of the present invention is to provide a basket-type endoscopic treatment tool that is difficult to incarnate and can be safely released even if it is incarcerated. do.

In order to achieve the above object, the treatment tool for a basket-type endoscope according to the present invention is inserted into a long cylindrical flexible sheath and the inside of the cylinder of the flexible sheath, and is pushed and pulled. An operation wire that can move forward and backward in the cylindrical direction in the axial direction, and a basket portion provided at the tip of the operation wire so that a plurality of basket wires made of stranded wires are elastically reduced in diameter or expanded. A tip tip having an inner diameter portion penetrating in a tubular shape and press-fitting a plurality of folded basket wires into the inner diameter portion to hold the tip, and a rear end tip holding the rear end sides of the plurality of basket wires together. It is provided with a tip fitting attached to the tip of the flexible sheath and through which an operation wire provided with the basket portion is inserted, and an operation portion for advancing and retreating the operation wire, and a direction toward the tip tip is provided. In a basket-type endoscope treatment tool called the tip side and the direction toward the operation portion is called the rear end side, the inner diameter portion of the tip tip is the basket wire on the rear end side of the folded tip of the basket wire. The first feature is that the narrow region of the inner diameter to be held and the thick region of the inner diameter that the basket wire extending to the rear end side of the narrow region can move inside are opened with a step .

Further, according to the present invention, in the basket-type endoscope treatment tool of the first feature, the length of the thick region of the tip is 1, 5 to 6 times the diameter of the thick region. Is the second feature.
Further, according to the present invention, in the basket-type endoscope treatment tool of the first or second feature, the tip tip is fitted and fixed to the tip tip body having the narrow region and the outer periphery of the tip tip body. The third feature is that the chip outer cylinder has the thick region .

Further, according to the present invention, in the basket-type endoscope treatment tool having any of the features 1 to 3, the tip metal fitting has a substantially cylindrical outer shape, is located on the rear end side in the axial direction, and has an inner diameter. Is located on the tip side and a large inner diameter portion substantially equal to the outer diameter of the flexible sheath, and the inner diameter is larger than the inner diameter of the flexible sheath and is larger than the outer diameter of the flexible sheath. Also has a small inner diameter portion with a small diameter, and when the operation wire is pulled to pull the basket portion into the flexible sheath, the rear end side of the tip tip becomes the tip of the flexible sheath. The fourth feature is to hit.

Further, according to the present invention, in the basket-type endoscope treatment tool having any of the features of the first to fourth aspects , the tip of the tip is crossed at the tip of the tip in a direction perpendicular to the cylinder axis. A fifth feature is that a cylindrical rod-shaped rib having a length is fixed, and the tip of at least one of the basket wires is hung on the rib.
Further, in the basket-type endoscope treatment tool having the fifth feature, a groove is formed at the tip of the tip tip in a direction perpendicular to the cylinder axis, and the rib is fixed to the groove. It is a feature of 6.
Further, according to the present invention, in the basket-type endoscope treatment tool of the sixth feature, the narrow region of the tip is arranged on the rear end side of the rib, and at least one of the basket wires is provided. The seventh feature is that the tip of the basket wire of the above is held in a narrow region of the tip.

Further, according to the present invention, in the basket-type endoscope treatment tool having any of the features 1 to 7, the tip fitting is made of a hard material having a substantially cylindrical outer shape, and is attached to the tip of the flexible sheath. The eighth feature is that the ring portion to be fitted is composed of a plurality of protrusions protruding at equal intervals in the direction of the basket portion of the ring portion.

In the treatment tool for an endoscope according to the present invention, the inner diameter portion of the tip tip has a narrow inner diameter region of the basket wire having a predetermined inner diameter for holding the basket wire together in the axial direction, and a rear end thereof than the narrow inner diameter region. Since the basket wire is located on the side and has a large inner diameter region larger than the small inner diameter region and the basket wire has a large inner diameter region that can be moved inside, the basket wire can move within the large inner diameter region when a calculus is grasped. It is difficult to squeeze, and even if it is incarcerated, it is possible to move the stone little by little by moving the basket wire, and gradually a gap is created between the basket wire and the calculus to release the incarceration. can.

The figure which shows the whole structure of the treatment tool for a basket type endoscope according to the Example of this invention. The figure which shows the tip of the tip of the treatment tool for a basket type endoscope according to Example 1 of this invention. The figure for demonstrating the tip tip and the tip metal fitting according to Example 1 of this invention. It is a figure for demonstrating the difference between the tip | tip of the treatment tool for a basket type endoscope according to Example 1 of this invention, and the conventional tip tip. The figure for demonstrating the dimension of the treatment tool for a basket type endoscope according to Example 1 of this invention. The figure which shows the tip of the tip of the treatment tool for a basket type endoscope according to Example 2 of this invention. It is a figure explaining the tip metal fitting of the treatment tool for a basket type endoscope according to Example 3 of this invention. The figure explaining the tip metal fitting of the treatment tool for a basket type endoscope according to Example 3 of this invention. The figure for demonstrating the operation example of the treatment tool for an endoscope to which this invention is applied.

Hereinafter, examples of the treatment tool for a basket-type endoscope according to the present invention will be described in detail with reference to the drawings. First, the overall structure of the treatment tool for a basket-type endoscope according to the embodiment of the present invention will be described. ..

[Overall structure]
As shown in FIG. 1, the basket-type endoscope treatment tool according to the present embodiment has an elongated flexible sheath 2 made of a resin, a coil, or the like to which an operation portion 10 is attached to a rear end, and the inside of the flexible sheath 2. An operation wire 3 that is freely inserted into and out of the operation wire 3, a cylindrical tip metal fitting 20 made of a hard metal material arranged at the tip of the flexible sheath 2, and an operation unit connected to the tip of the operation wire 3. It is provided with a basket portion 40 for crushing foreign matter, which is a treatment portion that can be recessed from the inside of the flexible sheath 2 by pushing the operation wire 3 toward the tip end side or pulling it toward the rear end side by the operation of 10.
In this embodiment, the direction toward the operation unit 10 on the right side of FIG. 1 is referred to as the rear end side, and the direction toward the tip 6 on the left and right sides of FIG. 1 is referred to as the tip side.

The operation unit 10 penetrates the grip portion 14 attached to the rear end of the operation wire 3 via the operation pipe 12 and the operation pipe 12 of the grip portion 14 attached to the operation wire 3, and the water supply port 13 opens. The operation unit main body 11 is provided so that the basket portion 4 at the tip of the operation wire 3 is recessed from the flexible sheath 2 by moving the grip portion 14 forward and backward. The water supply port 13 is configured such that the inner end portion communicates with the in-cylinder space of the operation unit main body 11 and an injection or the like (not shown) can be attached so that the chemical solution or the like can be sent into the flexible sheath 2.

The basket portion 4 is formed by folding a long linear stranded wire substantially at the center, and a plurality of wires having the folded portion as a tip (in the present embodiment, the basket portion 4 is a folded two basket wires 4). The basket wires 41 and 42 (consisting of a book), the tip 6 which is a feature of the present invention for holding the folded ends of the basket wires 41 and 42 together, and the rear ends of the basket wires 41 and 42 together. It consists of a rear end tip 7 to be fixed, and forms a treatment portion so that a plurality of basket wires 41 and 42 elastically contract or expand at intervals.

The basket portion 40 is self-urged so that the basket wires 41 and 42 are curved and bulge outward, and the basket wires 41 and 42 are three-dimensionally line-symmetric with the central axis of the basket portion 40 as the center of symmetry. It is arranged in a relationship, the diameter is reduced in the flexible sheath 2, and when it protrudes from the tip of the flexible sheath 2, it expands and expands by self-urging force to form a substantially cage shape. There is.

[Overall operation description]
The basket-type endoscopic treatment tool according to the present embodiment configured as described above is a calculus that is inserted into the patient's body cavity through the channel of the endoscope device previously inserted into the patient's body cavity and is a recovery target. It is used to crush, and an example of this procedure will be described with reference to FIG.

As shown in FIG. 9A, the treatment of this basket-type endoscope treatment tool is performed by a doctor pulling an operation wire to pull the basket portion at the tip into the inside to reduce the diameter of the flexible sheath. The step of inserting 2 into the bile duct 22 in the papilla 210 of the duodenum, and then, as shown in FIG. 9B, push out the operation wire to open the basket portion 4 from the tip of the flexible sheath 2 and deeper than the calculus 230. A step of moving the calculus to a position, then a step of projecting an operation wire and pulling it into the flexible sheath 2 to capture the calculus 230 in the gap of the basket portion 4, as shown in FIG. 9 (c), and further in FIG. 9 ( As shown in d), the basket portion 4 is further pulled into the flexible sheath 2, sandwiched between the tip fitting at the tip of the flexible sheath 2 and the basket portion 4, and the calculus 230 is tightened to crush the 230. ..

[Tip tip configuration]
Next, the tip 6 which is a feature of this embodiment will be described with reference to FIGS. 2 to 5.
2 (a) is an external view of the tip tip 6, FIG. 2 (b) is a view of (a) seen from the tip side (upward direction of (a)), and FIG. 2 (c) is (b). AA sectional view, FIG. 2 (d) is a sectional view taken along the line BB of (b), FIG. 2 (e) is a sectional view taken along the line CC of (a), and FIG. A cross-sectional view of D is shown, and the basket wires 41 and 42 show a closed state without spreading in a cage shape.

As shown in FIGS. 3A and 3B, the tip tip 6 is fitted into a tip portion 6e having a hemispherical shape at the tip side so as not to damage the inner wall of the body cavity, and a tip outer cylinder 6c having a rear end side described later. It is fitted to the outer periphery of the tip cylinder portion 6f of the tip main body 6a and the hollow tip main body 6a formed into a compatible tubular shape and having a tip cylinder portion 6f having a small inner diameter region a, and is fixed by laser welding or the like. It is composed of a cylindrical tip outer cylinder 6c and has a tubular inner diameter portion with a step as a whole.
As shown in FIG. 3B, this inner diameter portion is located in a small inner diameter region a having a predetermined inner diameter for collectively holding the basket wires 41 and 42, which will be described later, and on the rear end side of the small inner diameter region. The diameter is larger than the small inner diameter region a, and the basket wires 41 and 42 have a large inner diameter region b that can be moved inside.
The small inner diameter region is also referred to as a small region, and the thick inner diameter region is also referred to as a thick region.

As shown in FIG. 2D showing a cross section, the tip tip 6 showing the lateral appearance in FIG. 2A has a groove 6d in the center in the direction perpendicular to the cylinder axis at the tip of the tip portion 6e of the tip body 6a. Is formed, and a rod-shaped rib 6b on which the wire folding portion 41a of one of the basket wires 41 is hung is fitted and fixed in the groove 6d. A part of the basket wire 41 on the rear end side of the wire folded portion 41a and the wire folded portion 42a of the other basket wire 42 are press-fitted into the tip cylinder portion 6f, whereby C in FIG. 2 (a). -As shown in FIG. 2 (e) showing a cross section of C, a part of the outer periphery of the basket wires 41 and 42 is held in contact with the tip cylinder portion 6f, respectively.

On the other hand, the tip outer cylinder 6c has an inner diameter that fits on the outer periphery of the tip cylinder portion 6f, and as shown in FIGS. A large inner diameter region having a gap of 6 g corresponding to the thickness of the tip cylinder portion 6f is located between the circumference and the circumference.

In this embodiment, the basket wires 41 and 42 are configured so that the substantially central portion of the long wire-shaped stranded wire is folded back and the folded portion becomes the tip of the basket wire. The two basket wires 41 and 41 form a pair, and the two basket wires 42 and 42 form a pair of the basket portion 4, but the present invention is not limited to this.

[size]
Next, the dimensions of the tip tip 6, the tip metal fitting 20, and the flexible sheath 2 will be described with reference to FIG. 5 (basket wires 41, 42, rib 6b not shown). Note that specific examples of the dimensions of each member are not limited to this because the diameters of the basket wires 41 and 42 are 0.35 mm and two pairs of four basket wires are used.

As described above, the inner diameter L4 of the small inner diameter region a of the tip cylinder portion 6f of the tip tip 6 is a part of the rear end side of the wire folding portion 41a of one basket wire 41 and the wire folding of the other basket wire 42. The diameter is such that the portion 42a can be press-fitted and a part of the outer periphery of each of the basket wires 41 and 42 can be inscribed and held, for example, about 0.86 mm. Further, the length L2 of the small inner diameter region a needs to be long enough that the basket wire 42a does not come off during normal crushing and comes off when a strong traction force is applied at the time of incarceration, for example, about 1.5 mm. ..
The inner diameter L1 on the tip side of the tip portion 6e is larger than the inner diameter L4 of the tip cylinder portion 6f in order to accommodate the folded portion 41a and the rib 6b of the basket wire 41, and is, for example, about 1.2 mm.
The inner diameter L5 of the tip outer cylinder 6c is substantially the same as the outer diameter of the tip cylinder portion 6f because it fits with the tip cylinder portion 6f, and is, for example, about 1.2 mm.

The length L3 of the large inner diameter region b of the chip outer cylinder 6c needs to be a length that allows the basket wires 41 and 42 to be movable, and may be at least 1, 5 to 6 times the inner diameter L5. For example, it is about 2 mm, and the length L6 of the chip outer cylinder 6c is, for example, about 3 mm.
The outer diameter L7 of the tip outer cylinder 6c is smaller than the diameter L8 so that it can be inserted into the diameter L8 of the small inner diameter portion 20a of the tip metal fitting 20, for example, when the diameter L8 is 1.65 mm, the diameter L7 is 1. It is about .58 mm.

As shown in FIG. 3C, the tip metal fitting 20 has a small inner diameter portion 20a and a large inner diameter portion 20b, and the length L9 of the small inner diameter portion 20a is the tip portion 6e of the tip tip as described later. In order not to collide with the rear end, the length of the chip outer cylinder 6c is shorter than the length L6, for example, about 1.5 mm.
The outer diameter L10 of the flexible sheath 2 is substantially the same diameter for fitting and fixing to the large inner diameter portion 20a of the tip metal fitting 20, for example, about 2.15 mm, and the inner diameter L12 of the flexible sheath 2 is. The outer diameter of the chip outer cylinder 6c is smaller than the outer diameter L7, and is, for example, about 1.09 mm.

[effect]
In the basket-type endoscope treatment tool 1 shown in this embodiment, as described above, a gap of 6 g is provided between the basket wires 41 and 42 and the chip outer cylinder 6c, so that a gap is provided when a stone is grasped. Since the basket wires 41 and 42 move within the allowable range formed by 6 g, it is difficult to incarnate them, and even if they are incarcerated, it is easy to release the incarceration.
That is, in the basket-type endoscope treatment tool 1 according to the present embodiment, a gap 6 g is provided between the tip tip 6 and the inner circumference of the tip outer cylinder 6c in a state where the basket wires 41 and 42 are narrowed. As a result, as shown in FIG. 4A, even if the basket wires 41 and 42 (42 not shown) are expanded in a basket shape and a stone is caught inside the basket portion 40 and becomes stuck, the operation is performed. By pushing and pulling the wire 2, the basket wires 41 and 42 can be moved in the X direction (the direction in which the basket wires 41 and 42 expand and narrow in a cage shape) inside the chip outer cylinder 6c. The stone can be moved little by little, and a gap is gradually formed between the basket wires 41 and 42 and the stone to release the incarceration.

Further, in the basket-type endoscope treatment tool 1 according to the present embodiment, the basket wire 41 protrudes from the tip cylinder portion 6f without a gap when the tip outer cylinder 6c is not provided, as shown in FIG. 4 (b). While the bending angle θ2 from the portion is greatly bent, as shown in FIG. 4A, the bending angle θ1 from the portion protruding from the tip outer cylinder 6c is larger, so that the way of biting into the calculus is small. It has an effect that makes it difficult to get stuck.

Further, in the present basket-type endoscope treatment tool 1, the folded portion 42a of the other basket wire 42 is not hung on the rib 6b, and the tip cylinder portion 6f is press-fitted instead of being fixed by welding or the like. When a force is applied, the folded-back portion 42a of the basket wire 42 can be released from the tip 6 to release the incarceration.

Further, in the basket-type endoscope treatment tool 1 according to the present embodiment, by setting the dimensions of the chip outer cylinder 6c as described above, the inside of the chip outer cylinder 6c is oriented in the X direction shown in FIG. 4 (a). Since the basket wires 41 and 42 can be moved, they are difficult to fit, and even if they are fitted, they are easy to release. Further, by setting the dimensions of the tip outer cylinder 6c, the tip metal fitting 20, and the flexible sheath 2 as described above, when the basket portion 40 is pulled into the flexible sheath 2, FIG. 5 (b) shows. As shown (shown with the basket portion 40), the rear end of the chip outer cylinder 6c can hit the tip of the flexible sheath 2 and prevent the tip 6 from being drawn into the flexible sheath 2. The rear end of the tip portion 6e of the tip tip 6 does not collide with the tip metal fitting 20 and is not damaged.

Next, a second embodiment of the basket-type endoscope treatment tool 1 according to the present invention will be described with reference to FIG.
The parts other than those shown in FIG. 6 are the same as those in the first embodiment, and thus the description thereof will be omitted.
In the above-described embodiment, an example in which the tip tip 6 is formed by assembling the tip body 6a and the tip outer cylinder 6c has been shown, but the present invention is not limited to this, and the treatment tool 1 for a basket-type endoscope according to the second embodiment is used. For example, as shown in FIG. 6, the tip tip 30 may be formed as one member, the tip tip 30 may be formed in an outer tubular shape without providing a hemispherical tip portion, or the folded portion may be formed. Instead of using the provided basket wire, the basket wires constituting the basket portion may be bundled at the tip and fixed to the tip tip 30 by welding or the like.
The tip tip 30 has a small inner diameter region C for fixing the basket wire 31 on the tip side in the axial direction, and has a large inner diameter 30a on the rear end side, which is thicker than the narrow inner diameter region C and allows the basket wire 31 to move. Region d is formed. The length L13 of the large inner diameter region d is preferably about 2 mm, for example, when the diameter of the basket wire 31 is about 0.35 mm as in the above-mentioned Example 1.

As described above, the basket-type endoscope treatment tool according to the present embodiment is provided with a gap 30a between the basket wires 31 and 31 and the inner circumference of the portion where the large inner diameter region D of the tip tip 30 is located. As a result, as in the first embodiment, the basket wires 31 and 31 move within the allowable range formed by the gap 30a when the stone is grasped, so that the basket wires 31 and 31 are difficult to fit, and even if they are fitted, the fitting is released. Cheap.
By setting the inner diameter L14 and the outer diameter L15 of the thick inner diameter region D of the tip tip 30 in the same manner as the inner diameter L5 and the outer diameter L7 of the chip outer cylinder 6c of the first embodiment shown in FIG. Similarly, it is possible to prevent the rear end side of the tip tip 30 from hitting the tip of the flexible sheath 2 and being drawn into the flexible sheath 2.
Further, by setting the outer diameter L15 of the tip tip 30 to be smaller than the inner diameter L11 of the flexible sheath 2 of Example 1, the tip tip 30 does not hit the tip of the sheath and the entire basket including the tip tip is flexible. It becomes possible to move in the sex sheath 2, and in this case, the sheath and the basket portion can be taken out from the rear end of the sheath and replaced with a new basket.

Next, a third embodiment will be described with reference to FIGS. 7 and 8.
Since the parts other than the tip fittings shown in FIGS. 7 and 8 are the same as those in the first embodiment, the description thereof will be omitted.
In each of the above-described embodiments, an example in which the tip metal fitting is configured in a cylindrical shape is shown, but the tip fitting may be configured as follows.

As shown in FIG. 7, the tip metal fitting 50 of this embodiment is made of a hard metal material having a substantially cylindrical outer shape, and has an annular portion 51 fitted to the tip of the flexible sheath 2 and the annular portion 51. A notch 53, which is composed of a plurality of protrusions 52 projecting upward, and a plurality of basket wires 41 and 42 extending from the rear end tip 7 of the flexible sheath 2 are gaps between the plurality of protrusions 52. It is configured to spread outward from the circumference through, for example, it can be manufactured by removing one end side of a metal ring at equal intervals at regular intervals, or it can be manufactured by removing multiple protrusions on a metal ring. Can be manufactured by welding at equal intervals.

The notch 53 formed between the plurality of protrusions 52 is provided at least by the number of basket wires 41 and 42, and the height of the protrusions 52 expands the basket wires 41 and 42 as described later. The diameters of the basket wires 41 and 42 are required to be squeezed and brought into contact with the calculus, preferably about 2 to 3 times the diameters of the basket wires 41 and 42, and the width is the same as that of the basket wires 41 and 42. The diameter value or more is preferable.

In the tip metal fitting 50 configured in this way, when the basket wire 41 for gripping the calculus 230 is pulled toward the tip metal fitting 60 by using the conventional annular tip metal fitting 60 as shown in FIG. 8A, the calculus 230 is formed. When the lower end side presses the basket wire 41 against the opening of the tip fitting 60 by the force F, the plurality of basket wires 41 and 42 extending from the annular opening of the tip fitting 60 are plastically deformed (permanent strain) at the wire bent portion 45. ) Is generated and bent, and due to this bending, the basket wires 41 and 42 cannot be pulled in during the crushing operation of the calculus, and the calculus cannot be crushed. As shown in 8 (b), the root portions of the basket wires 41 and 42 are released in the circumferential direction, and the force F on the lower end side of the calculus 230 is not applied to the basket wires 41 and 42, so that the basket wires 41 and 42 are difficult to fit. ..

That is, in the case of the annular tip metal fitting 60 according to the prior art, the force F on the lower side of the calculus 230 is strongly applied to the roots of the basket wires 41 and 42 to deform by a relatively large angle θ3 and the opening of the tip metal fitting 60. In contrast, the tip metal fitting 50 according to the present embodiment allows the root portions of the basket wires 41 and 42 to escape in the circumferential direction through the notch 53 to greatly widen the bending angle θ4 and the force from the calculus 230. Since F is prevented from being applied to the basket wires 41 and 42, the basket wires 41 and 42 are not easily deformed and are not easily fitted.

In the basket-type endoscope treatment tool according to the present embodiment, as in the above-described embodiment, the basket wires 41 and 42 move within the allowable range for forming the gap due to the provision of the gap in the tip tip, so that stones are formed. It is difficult to incarnate when grasped, and even if it is incarcerated, it is easy to release the incarceration. Further, by configuring the tip metal fitting 50 as described above, when the calculus 230 is taken in and the calculus 230 is tightened to crush the calculus 230, the root portions of the basket wires 41 and 42 are released in the circumferential direction through the notch 53. In order to prevent the force F from the stone 230 from being applied, the basket wires 41 and 42 are less likely to be deformed and more difficult to be fitted.
Further, by setting the axial length of the tip metal fitting 50 including the protrusion 52 to be the same as the length of the tip metal fitting 20 of the first embodiment and setting the inner diameter to be the same as L8 and L10, the same as that of the first embodiment shown in FIG. Similarly, since the rear end of the tip outer cylinder 6c of the tip tip 6 hits the tip of the flexible sheath 2 and the tip tip 6 can be prevented from being drawn into the flexible sheath 2, the tip tip 6 can be prevented from being pulled into the flexible sheath 2. The rear end of the tip portion 6e does not collide with the protrusion 52 of the tip metal fitting 50 and is not damaged.

1 Basket-type endoscope treatment tool, 2 Flexible sheath, 3 Operation wire, 6 Tip tip,
6a insert body, 6b rib, 6c insert outer cylinder, 6d groove, 6e tip,
6f tip cylinder part, 6g gap, 7 rear end tip, 10 operation part,
20 Tip fitting, 20a small inner diameter part, 20b thick inner diameter part 40 basket part, 41 basket wire, 41a wire folding part,
42 basket wire, 42a wire folded part, small inner diameter area, thick inner diameter area,
50 Tip bracket, 51 Annulus, 52 Protrusion, 53 Notch

Claims (8)

With a long cylindrical flexible sheath,
An operation wire that is inserted into the cylinder of the flexible sheath and can be moved back and forth in the cylinder by pushing and pulling.
A basket portion provided at the tip of the operation wire and formed so that a plurality of basket wires made of stranded wires are elastically reduced in diameter or expanded.
A tip tip that has an inner diameter portion that penetrates in a cylindrical shape and presses and holds a plurality of folded basket wires into the inner diameter portion .
A rear end tip that collectively holds the rear end sides of the plurality of basket wires,
A tip fitting attached to the tip of the flexible sheath and through which an operation wire provided with the basket portion is inserted.
An operation unit for moving the operation wire forward and backward, and
In a basket-type endoscope treatment tool, the direction toward the tip of the tip is referred to as the tip side, and the direction toward the operation unit is referred to as the rear end side.
The inner diameter of the tip has a small area of inner diameter that holds the basket wire on the rear end side of the folded tip of the basket wire, and an inner diameter of which the basket wire extending toward the rear end side of the narrow area can move inside. A basket-type endoscopic treatment tool characterized in that the thick area of the wire is opened with a step . The treatment tool for a basket-type endoscope according to claim 1, wherein the length of the thick region of the tip is 1, 5 to 6 times the diameter of the thick region. 2 . A treatment tool for basket-type endoscopes. The tip fitting has a substantially cylindrical outer shape, is located on the rear end side in the axial direction, has a large inner diameter portion whose inner diameter is substantially equal to the outer diameter of the flexible sheath, and is located on the tip side, and has an inner diameter. It has a small inner diameter portion having a diameter larger than the inner diameter of the flexible sheath and a smaller diameter than the outer diameter of the flexible sheath.
Claims 1 to 3, wherein the rear end side of the tip end abuts on the tip of the flexible sheath when the operation wire is pulled to pull the basket portion into the flexible sheath. The basket-type endoscopic treatment tool described in any of the above. A cylindrical rod-shaped rib having a length that crosses the tip tip in a direction perpendicular to the cylinder axis is fixed to the tip of the tip, and the tip of at least one of the basket wires is the rib. The basket-type endoscopic treatment tool according to any one of claims 1 to 4, wherein the treatment tool is hung on a basket-type endoscope. The treatment tool for a basket-type endoscope according to claim 5, wherein a groove is formed at the tip of the tip tip in a direction perpendicular to the cylinder axis, and the rib is fixed to the groove. The narrow region of the tip tip is arranged on the rear end side of the rib.
The treatment tool for a basket-type endoscope according to claim 6, wherein the tip of at least one of the basket wires is held in a narrow region of the tip. The tip fitting is made of a rigid material having a substantially cylindrical outer shape, and has an annular portion that fits into the tip of the flexible sheath and a plurality of protrusions that project at equal intervals in the basket portion direction of the annular portion. The treatment tool for a basket-type endoscope according to any one of claims 1 to 7, wherein the treatment tool is configured.

Images