TREATMENT SYSTEM AND APPLICATOR

A treatment system includes: an implant placed in a body; an insertion portion that is inserted into the body; and a flap having a first end and a second end located at a position closer to a distal end than the first end, the flap extending from the first end to the second end, wherein the second end has a receiving portion through which the implant can enter, and can be arranged at a spaced position, the spaced position being a position more spaced from a central axis of the insertion portion than the first end, and the flaps support the implant by abutting against the implant placed in the body.

BACKGROUND

Technical Field

The present invention relates to a treatment system and an applicator.

Background

Ligation using a clip unit is a known procedure performed using an endoscope. Japanese Patent (Granted) Publication No. 5750620 (hereinafter referred to as Patent Document) discloses a clip unit including a pair of arms. In a state where a pair of arms are pulled by a predetermined amount while the pair of arms sandwich a tissue, the pair of arms are locked with the tissue strongly tightened.

In a state where the area to be ligated is wide, a plurality of clip units may be placed in the tissue. For example, when a new clip unit is placed near a clip unit that has already been placed, the clip unit that has already been placed may interfere with the treatment.

The present invention provides a treatment system capable of performing treatment while suppressing interference of surrounding structures.

A treatment system includes: an implant placed in a body; an insertion portion that is inserted into the body; and a flap having a first end and a second end located at a position closer to a distal end than the first end, the flap extending from the first end to the second end, wherein the second end has a receiving portion through which the implant can enter, and cats be arranged at a spaced position, the spaced position being a position more spaced from a central axis of the insertion portion than the first end, and the flap support the implant by abutting against the implant placed in the body.

The treatment system may further include: an operation wire separably connected to at least one of the first arm and the second arm; and a tubular holding tube into which at least one of the first arm and the second arm is inserted.

The first end may be fixed to the insertion portion al a position closer to a distal end of the first arm and a distal end of the second arm, and the second end may be located closer to the distal end of the first arm and the distal end of the second arm.

The first end may be fixed to the insertion portion at a a more proximal end side position than a distal end of the first arm and a distal end of the second arm, the second end may be located closer a proximal end side than the distal end of the first arm and the distal end of the second arm, and in a state where the second end is arranged at the spaced position, a length from the distal end of the first arm to the second end in a direction along the central axis and a length from the distal end of the second arm to the second end in the direction along the central axis may be shorter than a maximum length of the implant.

The first end may be configured to be movable in a direction along the central axis with respect to the first arm and the second arm.

An applicator to which a clip unit having a first arm and a second arm is separably connected includes: an insertion portion configured to be inserted into a body; and a plurality of flaps extending from a first end to a second end arranged on a more distal end side than the first end, wherein the second end is arranged at a spaced position, the spaced position being a position more spaced from a central axis of the insertion portion than the first end, and in a state where the clip unit and the applicator are connected, the spaced position of the second end of at least one of the flaps is located on a second plane that intersects the first plane including the first arm, the second arm, and the central axis of the insertion portion.

The second end may be capable of being moved to a closer position, the closer position being a position closer to the central axis than the spaced position.

The applicator may further include: an outer sheath having a tubular shape into which the insertion portion and the flap can be inserted, wherein the second end may be urged in a direction away from the central axis, and the second end may move to the spaced position by moving from an inside of the outer sheath to an outside.

The first end may be configured to be movable in a direction along the central axis with respect to the insertion portion.

The first end may be fixed to the distal end of the insertion portion.

According to the present invention, treatment can be performed while suppressing interference of the indwelling objects existing in the surroundings.

DETAILED DESCRIPTION

FIG. 1is a partial cross-sectional view of a ligation device1, which is the treatment tool of the present embodiment. The ligation device1includes a clip unit (hereinafter, abbreviated as “clip”)10and an applicator40. The clip10is removably connected to the distal end of the applicator40. In the present embodiment, the clip10and the applicator40are connected by a connecting member63.

As shown inFIG. 1, the clip10has an arm member (arm portion)11including a first arm12and a second arm13. In the following description of the present embodiment, a direction in which the first arm12and the second arm13face each other is defined as a facing direction X, a direction parallel to the axis C1of the holding tube31is defined as an axial direction Y, and a direction orthogonal to both the facing direction X and the axial direction Y is defined as an orthogonal direction Z. In the present embodiment, the axis C1coincides with the central axis of the clip10and the insertion portion60of the applicator40described later. Therefore, in the following description, the axis C1may be referred to as the “central axis C1”.

As shown inFIG. 1, the clip10includes an arm member11and a holding tube31. The holding tube31is formed in a cylindrical shape and has an inner diameter through which the proximal end portion of the arm member11can enter. That is, the holding tube31is formed with a lumen into which the arm member11having the first arm12and the second arm13can enter.

(Structure of Arm Member11)

The arm member11has a first arm12, a second arm13, and an intermediate portion14. The first arm12and the second arm13extend from the proximal end side toward the distal end side and are arranged so as to face each other. The intermediate portion14is located between the proximal end of the first arm12and the proximal end of the second arm13. In the side view shown inFIG. 1, the first arm12and the second arm13are formed at positions line-symmetric with respect to the axis C1.

The first arm12and the second arm13are naturally spaced from each other, and the distance between them increases as they approach the distal end. In the present specification, the “natural state” means a state in which an external force does not act on the arm member11. For example, the state in which the first arm12and the second arm13do not receive a force from the inner peripheral surface of the holding tube31is a natural state. A claw12aextending toward the second arm13side is formed at the distal end of the first arm12. A claw13aextending toward the first arm12side is formed at the distal end of the second arm13.

The first arm12and the second arm13have an arcuate cross-sectional shape orthogonal to the longitudinal direction on the distal end side, and are formed into a rounded shape. By forming the first arm12and the second arm13in this shape, the strength against bending is improved, the frictional resistance with respect to the outer sheath50described later is reduced, and the first arm12and the second arm13can move forward and backward smoothly.

FIG. 2is a cross-sectional view of the connecting portion between the clip10and the applicator40as viewed from a direction different from that ofFIG. 1.

As shown inFIG. 2, two first locked portions16and17are provided at the proximal end portion of the first arm12. The first locked portions16and17protrude from the first arm12in the Z direction. The first locked portions16and17protrude in opposite directions to each other.

In the plan view shown inFIG. 2, the first locked portion16and the first locked portion17are line-symmetric with respect to the axis C1. The proximal end surface of the first locked portion16is spaced from the central axis C1toward the distal end side and is inclined with respect to the central axis C1. The distal end surface161of the first locked portion16is perpendicular to the axial direction Y. The proximal end surface17aof the first locked portion17and the proximal end surface16aof the first locked portion16are line-symmetric with respect to the axis C1. The distal end surface17bof the first locked portion17and the distal end surface16bof the first locked portion16are line-symmetric with respect to the axis C1.

In the first arm12, two protrusions18and19are provided on the distal end side of the first locked portions16and17. As shown inFIG. 2, the protrusions18and19protrude from the first arm12in the Z direction. The protrusion18and the protrusion19are line-symmetric with respect to the axis C1in plan view. The length of the protrusions18and19protruding from the first arm12may be longer than the length of the first locked portions16and17protruding from the first arm12in the orthogonal direction Z.

The second arm13is provided with second locked portions21,22and protrusions23,24formed in the same manner as the first locked portions16,17and the protrusions18,19of the first arm12. That is, the second locked portions21and22protrude in the Z direction. The protrusions23and24are provided on the distal end side of the second arm13with respect to the second locked portions21and22, and protrude from the second arm13in the Z direction. The second locked portions21and22and the protrusions23and24, and the first locked portions16and17and the protrusions18and19, are arranged side by side in the facing direction X, respectively. In the plan view shown inFIG. 2, the second locked portions21and22overlap the first locked portions16and17, respectively, and the protrusions23and24overlap the protrusions18and19, respectively.

(Structure of Holding Tube31)

On the inner peripheral surface of the holding tube31, a stepped portion (engaging portion)15is provided so as to protrude inward of the holding tube31over the entire circumference. The inner diameter of the holding tube31is small at the position where the stepped portion15is provided. In the present embodiment, the position where the stepped portion15is provided on the inner peripheral surface along the longitudinal direction of the holding tube31is not particularly limited. For example, the stepped portion15may be provided on the inner peripheral surface on the distal end side of the holding tube31.

In the present embodiment, the protrusions (engaged portions)18,19,23, and24provided on the arm member11engage with the stepped portion15so as to be capable of restricting the arm member11from advancing with respect to the holding tube31. The shape of the stepped portion15including the length protruding inward of the holding tube31is not particularly limited, but may be formed according to the shapes of the protrusions18,19,23, and24of the arm member11described later, for example. Specifically, for example, slopes may be provided on the distal end side and the proximal end side of the stepped portion15along the longitudinal direction of the holding tube31. Further, slopes may be provided at both ends of the protrusions18,19,23, and24in the radial direction corresponding to the slopes provided on the stepped portion15. By configuring the stepped portion15and the protrusions18,19,23, and24according to the present embodiment in this way, when the arm member11moves forward and backward along the longitudinal direction of the holding tube31, the protrusions18,19,23, and24can easily move forward and backward while contacting the stepped portion15.

On the inner peripheral surface of the holding tube31located closer to the proximal end side than the stepped portion15, the locking portion32is formed so as to protrude in the direction toward the inside of the holding tube31. In other words, the locking portion32is formed so as to protrude from the inner peripheral surface of the holding tube31in the direction toward the axis C1. In the present embodiment, in order to secure a space for press-fitting the connecting member63described later from the opening on the proximal end side of the holding tube31, the locking portion32is formed at a predetermined distance on a more distal end side than the proximal end of the holding tube31. That is, in the holding tube31, the locking portion32is formed at a position between the proximal end of the holding tube31and the stepped portion15.

The edge portion32aon the axis C1side of the locking portion32is formed in a circular shape coaxial with the holding tube31. The portion of the first arm12on the proximal end side of the protrusions18and19, the portion of the second arm13on the proximal end side of the protrusions23and24, and the intermediate portion14can pass through the locking portion32. Although the details will be described later, the first locked portions16and17formed on the first arm12and the second locked portions21and22formed on the second arm13pass over the locking portion32and come into contact with the locking portion32on the proximal end side of the locking portion32, thereby being locked to the locking portion32. In the present embodiment, the first locked portions16and17and the second locked portions21and22are locked to the locking portion32, so that the movement of the arm member11toward the distal end side with respect to the holding tube31can be restricted.

Further, as shown inFIG. 1, a tapered surface31ais formed on the inner peripheral surface of the distal end portion of the holding tube31over the entire circumference. The diameter of the tapered surface31aincreases toward the distal end side.

These members constituting the clip10, including the arm member11, are formed of a material such as a cobalt-chromium alloy, titanium, or stainless steel. The clip10is configured so that it can be observed under MRI (magnetic resonance imaging) fluoroscopy.

The arm member11is formed by punching, for example, a plate material made of a cobalt-chromium alloy or the like into a shape in which the first arm12, second arm13, intermediate portion14, first locked portions16,17, second locked portions21,22, protrusions18,19,23,24are developed in a plane. The arm member11bends the punched member at the connecting portion between the first arm12and the intermediate portion14and the connecting portion between the second arm13and the intermediate portion14, so that the intermediate portion14and its surroundings are substantially C-shaped in side view and are integrally formed.

Next, the configuration of the applicator40will be described.

As shown inFIG. 1, the applicator40has an outer sheath50, an insertion portion60, and an operation portion100. The insertion portion60has a dimension capable of advancing and retracting in the outer sheath50. The operation portion100is attached to the proximal end portion of the insertion portion60.

The outer sheath50can be formed of, for example, a fluororesin such as PTFE (polytetrafluoroethylene) or a resin material such as HDPE (high-density polyethylene).

The insertion portion60includes a sheath portion61, an operation wire (wire)62, and a connecting member63. The operation wire62is inserted through the sheath portion61so as to be capable of moving forward and backward. The connecting member63is provided to connect the holding tube31and the sheath portion61.

In the present embodiment, the sheath portion61has a coil sheath66and a distal end member67fixed to the distal end portion of the coil sheath66. The coil sheath66is formed of, for example, stainless steel such as SUS301 having high compressive strength. Specifically, as the coil sheath66, a coil formed by tightly winding a wire (not shown) in the axial direction Y can be used. The coil sheath66has flexibility and is strong against a compressive force in the axial direction Y.

The distal end member67is formed of, for example, stainless steel in a cylindrical shape. The outer diameter of the distal end member67is larger than the outer diameter of the coil sheath66and the holding tube31. The distal end member67and the coil sheath66are connected by laser welding or the like.

The operation wire62is formed of, for example, a single metal wire or a stranded wire. The distal end of the operation wire62is connected to the proximal end portion of the enlarged diameter portion72. A loop portion73and a hook portion77are connected to the distal end portion of the enlarged diameter portion72. In the present embodiment, the operation wire62, the enlarged diameter portion72, the loop portion73, and the hook portion77are integrally configured and can move forward and backward together. Therefore, in the present embodiment, the enlarged diameter portion72, the loop portion73, and the hook portion77will be described as a part of the operation wire66as an extension of the operation wire62.

The enlarged diameter portion72is formed in a cylindrical shape with, for example, metal. The outer diameter of the enlarged diameter portion72is smaller than the inner diameter of the coil sheath66and the connecting member63. Further, the outer diameter of the enlarged diameter portion72is larger than the inner diameter of a through-hole631formed in the proximal end portion63B of the connecting member63. That is, the enlarged diameter portion72cannot pass through the through-hole631.

The loop portion73is formed by folding back one wire73a.The folded portion of the wire73ais located on the distal end side, and both ends located on the proximal end side are fixed to the enlarged diameter portion72by brazing, resistance welding, or the like.

The hook portion77is connected to the distal end side of the loop portion73. In the present embodiment, the hook portion77can connect the clip10and the applicator40by engaging with the intermediate portion14of the arm member11. When the hook portion77rotates with respect to the loop portion73, the engagement between the hook portion77and the central portion intermediate portion14is released. That is, the operation wire62is removably connected to the arm member11.

As shown inFIGS. 1 and 2, the connecting member63is a tubular member having an outer diameter substantially equal to the inner diameter of the holding tube31and the inner diameter of the coil sheath66. At the distal end portion63A of the connecting member63, a lumen is formed that has an inner diameter that allows the enlarged diameter portion72, the loop portion73, the hook portion77, and the first arm12and the second arm13of the arm member11to enter. On the other hand, the inner diameter of the connecting member63is reduced in a part of the proximal end portion63B. Specifically, the connecting member63is formed with the through-hole631at the proximal end portion63B, which is smaller than the outer diameter of the enlarged diameter portion72and has an inner diameter equal to or larger than the outer diameter of the operation wire62.

In the present embodiment, the material forming the connecting member63is not particularly limited, but for example, a material that can be elastically deformed can be used. When the connecting member63is configured as described above, the distal end portion63A is press-fitted into the holding tube31from the proximal end side of the holding tube31, and the proximal end portion63B can be press-fitted into the coil sheath66from the distal end side of the coil sheath66. In the present embodiment, the distal end portion63A of the connecting member63is press-fitted into the holding tube31, and is brought into close contact with the inner peripheral surface of the holding tube31located closer to the proximal end side than the locking portion32, so that a frictional force is generated between the connecting member63and the holding tube31. Similarly, the proximal end portion63B of the connecting member63is press-fined into the distal end portion of the coil sheath66to bring them into close contact with each other, so that a frictional force is generated between the connecting member63and the coil sheath66. The frictional force (static friction force) between the connecting member63and the holding tube31or the coil sheath66is determined by the static friction coefficient determined by the material forming the connecting member63, the holding tube31and the coil sheath66and the degree of adhesion (that is, the force of pressing) between the connecting member63and the holding tube31or the coil sheath66.

In the present embodiment, by the frictional force between the connecting member63and the holding tube31and the frictional force between the connecting member63and the coil sheath66, the holding tube31and the coil sheath66are connected by the connecting member63. In the natural state where no external force acts, the connection state between the holding tube31and the coil sheath66is not released. That is, in the endoscope clip1according to the present embodiment, the holding tube31and the coil sheath66are connected and integrated by the connecting member63. The holding tube31and the coil sheath66are fixed by the connecting member63, and do not move relative to the axis C1direction of the holding tube31. Therefore, when the operator pushes the slider102toward the distal end side to move the operation wire62toward the distal end side, the holding tube31does not move toward the distal end side.

In a state where the operation wire62and the enlarged diameter portion72connected to the distal end side of the operation wire62are pulled back to the proximal end side and the proximal end surface of the enlarged diameter portion72in contact with the proximal end portion63B of the connecting member63, when the force for pulling back the operation wire62becomes larger than the maximum static friction force between the connecting member63and the holding tube31or the coil sheath66, the connecting member63can be pulled back to the proximal end side, in this state, the connecting member63can be moved to the proximal end side with respect to the holding tube31and the coil sheath66.

At the distal end portion63A of the connecting member63, a lumen having an inner diameter larger than the outer diameter of the enlarged diameter portion72, the loop portion73, and the hook portion77is formed. Here, the outer diameters of the enlarged diameter portion72, the loop portion73, and the hook portion77mean the maximum dimensions in the radial direction orthogonal to the central axis C1in these configurations. In the present embodiment, the hook portion77cannot rotate with respect to the loop portion73from the state where the hook portion77is located on the distal end side of the loop portion73in the holding tube31and the connecting member63. In other words, the holding tube31and the distal end portion63A of the connecting member63restrict the relative movement of the arm member11and the hook portion77in the radial direction.

The above-mentioned “the hook portion77cannot rotate with respect to the loop portion73” means that the hook portion77cannot rotate with respect to the loop portion73to the extent that the hook portion77and the intermediate portion14are disengaged. Therefore, “the hook portion77cannot rotate with respect to the loop portion73” does not mean that “the hook portion77cannot rotate with respect to the loop portion73”.

As shown inFIG. 1, the operation portion100has an operation portion main body (handle)101and a slider102.

The operation portion main body101is attached to the proximal end portion of the coil sheath66. The operation portion main body101is formed in a rod shape extending in the axial direction Y, and a finger hook portion101a,is provided at the proximal end portion. A slit101bextending in the axial direction Y is formed in the operation portion main body101.

The operation portion main body101is inserted through the slider102. The slider102can slide (forward and backward) in the axial direction Y with respect to the operation portion main body101. The proximal end of the operation wire62is connected to the slider102. When the slider102is moved forward or backward, the operation wire62moves forward or backward in the axial direction Y. By advancing and retracting the operation wire62, the enlarged diameter portion72, the loop portion73, the hook portion77, and the arm member11of the clip10provided on the distal end side of the operation wire62can be advanced and retracted. As a result, the pair of the first arm12and the second arm13of the arm member11can be opened and closed.

The slider102is formed in a cylindrical shape. A recess102ais formed on the outer peripheral surface of the slider102over the entire circumference. The slider102is formed with a flange portion102b,a recess102a,and a flange portion102cin this order from the distal end side to the proximal end side in the axial direction Y. The pair of collar portions102band102chave an elliptical shape when viewed in the axial direction Y. As a result, the slider102can be easily gripped, and space can be saved when packing the operation portion100of the endoscope clip1.

By engaging the slider102with the slit101bof the operation portion main body101, the movement range of the slider102in the axial direction Y with respect to the operation portion main body101is limited.

As shown inFIGS. 1 and 2, a flap80is attached to the outer peripheral surface of the distal end member67.

FIG. 3shows the appearance of the clip10and the flap80. The four flaps80are made of metal and have a rectangular frame-like basic shape with some parts removed. Each flap80has a proximal end portion (first end)81fixed to the coil sheath66and an expansion portion82connected to the proximal end portion81. The distal end (second end) portion82aof the expansion portion82is located closer to the proximal end side than the distal end of the first arm12and the distal end of the second arm13, and each has an arc-shaped notch (reception portion)83. The expansion portion82has a through-hole82bin a part on the proximal end side of the notch82a.

The proximal end portion81is fixed to the outer peripheral surface of the distal end member67by welding or the like. The fixed positions of the flaps are arranged at equal intervals in the circumferential direction of the outer peripheral surfaces of the coil sheath66and the distal end member67, that is, at intervals of about 90° in phase. Of the four flaps80, the phases of the two auxiliary flaps80A coincide with the first arm12and the second arm13, so that the auxiliary flap80A is located on a plane (first plane) including the first arm12, the second arm13, and the central axis C1. The other two flaps80are located on a plane (second plane) orthogonal to the first plane and substantially parallel to the central axis C1.

A bending habit is attached to the boundary portion between the proximal end portion81and the expansion portion82. Therefore, the expansion portion82of each flap80is substantially parallel to the axis C1along the inner surface of the outer sheath50inside the outer sheath50, and as shown inFIG. 3, it opens in the direction away from the holding tube31as it approaches the distal end outside the outer sheath50. As a result, the distance between the distal end portion82aand the central axis C1is longer than the distance between the proximal end portion81and the central axis.

The angle formed by the proximal end portion81and the expansion portion82outside the outer sheath50can be appropriately adjusted. Examples of the material for forming the flap80include shape memory alloys such as stainless steel, cobalt-chromium alloys, and nickel titanium alloys.

The operation when the ligation device1configured as described above is used will be described. The ligation device1is introduced into the body via the endoscopic channel. When inserting the ligation device1into the endoscope, the user accommodates the clip10and the flap80in the outer sheath50. Inside the outer sheath50, the distal end portion82aof the flap80moves to a position (closer position) closer to the central axis C1than the position (spaced position) when it is outside the outer sheath50.

When the ligation device1is protruded from the channel opening at the distal end of the endoscope and the outer sheath50is retracted with respect to the coil sheath66, the first arm12and the second arm13are first opened by the elastic restoring force of the arm member11. Subsequently, each flap80opens according to its bending habit by its own elastic restoring force.

The user moves the first arm12and the second arm13in the open state to positions sandwiching the target tissue. The first arm12and the second arm13are in a half-open state in which the target tissue of an average size can be ligated in a state where the protrusions18,19,23, and24are in contact with the stepped portion15. In a state where the target tissue is large, force is applied to the slider102to move it forward. As a result, the protrusions18,19,23,24can pass over the stepped portion15and open the first arm12and the second arm13more widely.

As shown inFIG. 4, when another clip unit (implant)10A is already placed near the target tissue T, the clip unit10A may interfere with the clip10due to falling toward the clip10or the like, which may interfere with the procedure. However, in the ligation device1, since the flap80spreads around the clip10, if the indwelling clip unit falls down, there is a high possibility that the flap80is first hit and supported. As a result, it is possible to preferably prevent the indwelling clip unit from interfering with the clip10and interfering with the procedure.

When it is determined that the tissue located between the first arm12and the second arm13may be ligated, the user retracts the slider102with respect to the operation portion main body101. When the slider102retracts, the operation wire62is pulled, and the first arm12and the second arm13enter the holding tube31while sandwiching the tissue.

When the user grasps the operation portion main body101and pulls back the slider102further, the first locked portions16and17and the second locked portions21and22come into contact with the locking portion32of the holding tube31, which is a contact state. In this process, first, as shown inFIG. 5, the proximal end of the first locked portion16on the proximal end surface16acomes into point contact at the position P1on the edge portion32aof the holding tube31, and the proximal end of the second locked portion17on the proximal end surface17amakes point contact at the position P2on the edge portion32a, of the holding tube31.

When the user further pulls back the slider102from the contact state, the arm member11is further moved to the proximal end side. At that time, the first arm12and the second arm13are elastically deformed in the direction approaching each other and pass through the locking portion32. Specifically, the first locked portions16and17of the first arm12pass through the locking portion32in an elastically deformed state. At this time, the first locked portion16moves while making point contact with the locking portion32, and the edge portion32aof the locking portion32with which the first locked portion16makes contact changes from the position P1to the position P3shown inFIG. 6. At the same time, the first locked portion17moves while making point contact with the locking portion32, and the edge portion32aof the locking portion32with which the first locked portion17makes contact changes from the position P2to the position P4. Further, both ends of the intermediate portion14are elastically deformed and approach the axis C1.

As a result of the above process, as shown inFIG. 6, both the distal end of the proximal end surface16aof the first locked portion16and the distal end of the proximal end surface17aof the first locked portion17come into contact with the edge32aof the locking portion32. The arm member11is in a riding state in which the first locked portions16and17and the second locked portions21and22pass over the locking portion32. At this time, the first arm12and the second arm13of the arm portion11remain in the closed form. In the riding state, as shown inFIG. 6, the distance between the position P3and the position P4of the edge portion32ais equal to the length L1of the first locked portions16and17.

When the user further pulls back the slider102from the riding state, the first locked portions16,17and the second locked portions21,22move beyond the locking portions32and further toward the proximal end side. Both the configuration on the distal end side of the first locked portions16and17in the first arm12and the configuration on the distal end side of the second locked portions21and22in the second arm13sequentially pass through the locking portion32.

The first arm12, the second arm13, and the intermediate portion14that have passed through the locking portion32are not urged by the locking portion32. Therefore, due to the elastic force of the intermediate portion14, as shown inFIG. 7, the proximal end side of the first arm12and the proximal end side of the second arm13move in the facing direction X and are spaced from each other.

When the traction of the slider102is released, the distal end surfaces of the first locked portions16and17and the second locked portions21and22of the arm member11come into contact with the proximal end surface32bof the locking portion32and are locked. As a result, in the arm member11, the first arm12and the second arm13are closed, and the state in which the first arm12and the second arm13are tightly bound to the target tissue is maintained.

In parallel with the operation of the first locked portion and the second locked portion passing through the locking portion, the enlarged diameter portion72comes into contact with the proximal end portion63B of the connecting member63, and the connecting member63is retracted with respect to the holding tube31and the coil sheath66. When the entire connecting member63moves out of the holding tube31, the connection between the holding tube31and the sheath portion61is released. As a result, the hook portion77can rotate with respect to the loop portion73. When the hook portion77rotates with respect to the loop portion73, the connection between the arm member11and the operation wire62is released.

Finally, the clip10is spaced from the applicator40and placed in a ligated state of the target tissue T.

As described above, in the ligation device1of the present embodiment, during the indwelling procedure of the clip10, in order for the flap80to suppress interference of various structures such as other implants that have been indwelled and tissues that are not the target of the procedure, for example, even in the case where a plurality of clip units are placed at narrow intervals to stop bleeding at a relatively large bleeding point, the procedure can be smoothly performed.

The flap80has a notch82aat the distal end82. When the size of the notch82ais set to a size that allows the holding tube of the clip unit10A to enter, the holding tube of the clip unit10A that has fallen down can be suitably received. As a result, interference prevention performance is improved.

Further, since the flap80has a through-hole82b,the front of the flap80can be visually recognized through the through-hole82bin endoscopic observation. Therefore, the flap80is less likely to obstruct the view.

Further, the flap80has a bending habit at the boundary between the proximal end portion81and the distal end portion82and has an elastic restoring force. Therefore, it can be accommodated in the outer sheath50by simply protruding it from the outer sheath50to expand to a predetermined state and retracting it. The ligation device1has a configuration that allows the flap80to be easily brought into a desired state.

In the present embodiment, an example in which four flaps are provided has been described, but the number of flaps is not limited to this.

FIG. 8shows a modified example of the configuration in which the auxiliary flaps are not provided and only the two flaps80are provided. InFIG. 8, one of the flaps80is hidden and invisible. In this modification, the two flaps80and the open first arm12and second arm13can be used to push away surrounding structures such as the indwelling clip unit.

In the case of this modification, if the phases of the first arm12and the second arm13and the phases of the two flaps are substantially the same, an interference suppression effect is reduced. Therefore, it is preferable that the ligation device have a structure in which the sheath and the arm member do not easily rotate relative to the axis C1. In the ligation device1, since the pressing tube31and the inserting portion60are connected by the connecting member63, the pressing tube31and the inserting portion60are unlikely to rotate relative to each other. Therefore, the configuration of the modified example can be suitably applied to the ligation device1.

On the other hand, in the configuration of the first embodiment including four flaps, even if the phases of the first arm12and the second arm13and the phases of the two flaps are substantially the same, the remaining flaps sufficiently suppress interference. In order to obtain the effect, the holding tube31and the insertion portion60do not necessarily have to have a structure in which they are difficult to rotate relative to each other.

In the present embodiment, the positional relationship between the first arm12, the second arm13, and the flap80in the circumferential direction of the sheath portion can be appropriately set. The ligation device may be configured so that the arm member11can be rotated around the axis C1with respect to the holding tube31, and the positional relationship between the first arm12and the second arm13and the flap80may be changed.

In the flap80, the presence/absence and shape of the notch82a,and the presence/absence, shape, size and the like of the through-hole82bmay be appropriately set.

Further, the length of the flap80can also be appropriately set according to the dimensions of the structure for which interference is desired to be suppressed. For example, when the distance L1(seeFIG. 3) in the direction in which the central axis C1extends between the tip of the first arm12or the second arm13and the distal end portion82aof the flap at the spaced position is set to be equal to or less than the maximum length L2of the implant in the indwelling state (the case of the clip unit10A is shown inFIG. 4), the flap can be used to easily push or catch the structure.

The structure in this embodiment is not limited to an artificial object such as the implant described above. For example, living tissues such as folds F of the large intestine shown inFIG. 9are also included. That is, interference between the clip10and the fold F can be suppressed by pressing the fold F using the flap80. Thereby, for example, a procedure for stopping bleeding at the bleeding point Bp located behind the fold F can be easily performed.

A second embodiment of the present invention will be described with reference toFIGS. 10 to 12. In the following description, the same reference numerals will be given to the configurations common to those already described, and duplicate description will be omitted.

FIG. 10shows the distal end of the ligation device301according to the present embodiment. A rod-shaped flap380is attached to the distal end member67in a positional relationship substantially similar to that of the flap80.

As the flap380, a wire or the like formed of the same material as the flap80can be used. A thread381is attached to the distal end of each flap380, and the thread380is stretched between the distal ends of adjacent flaps380. The material of the thread380is not particularly limited as long as it has enough flexibility to be folded in half in the outer sheath50.

FIG. 11shows an example of the usage state of the ligation device301. Unlike the first embodiment, the flap380does not have a through-hole, but is sufficiently thin as to not obstruct the view of the endoscope. The thread381arranged between the flaps380deforms according to the outer shape of the clip unit10A or the like in contact with the flap380, and preferably receives or pushes away the surrounding structure to prevent it from interfering with the clip unit10being indwelled.

When the flap380and the thread381are pulled into the outer sheath50, the flap380becomes substantially linear and the thread381is folded so that the flap380and the thread381are smoothly housed in the outer sheath50.

Similar to the ligation device1of the first embodiment, the ligation device301of the present embodiment can smoothly perform the procedure even when a plurality of clip units are placed at narrow intervals.

FIG. 12shows a modified example of this embodiment. In this modification, instead of the thread381, a transparent flexible film382is arranged between the adjacent flaps380. As the film382, a film made of various resins, cellophane, or the like can be used. In this modification, the film382suppresses interference with surrounding structures. Since the film382has transparency, the front of the film382can be confirmed endoscopically through the film382.

Creases may be formed in the film382for the purpose of being smoothly accommodated in the outer sheath50.

In the present embodiment, the attachment positions and dimensions of the thread381and the film382can be appropriately set. For example, the thread381may not be attached to the distal end of the flap380, or may be a wide strip-shaped member. Further, the film382does not necessarily have to be arranged in the entire flap380space, and may be arranged in a part of the flap380space.

Also in this embodiment, the number of flaps and the arrangement mode can be appropriately set. Further, the thread or the film does not have to be arranged between some flaps.

FIG. 13shows the distal end of the ligation device401according to the present embodiment. A net-like flap480is attached to the distal end member67. The flap480is formed by knitting a plurality of strands480aand has a self-expansion property. Such flaps480can be formed in a manner similar to known self-expanding stents. Examples of the material of the wire are metal, resin, and the like.

Outside the outer sheath50, the flap480expands to a shape that covers the periphery of the clip10as shown inFIG. 13due to self-expansion. The front of the flap480can be observed endoscopically through the mesh of the flap480. When the flap480is pulled into the outer sheath50, the distance between the strands480ais shortened to reduce the diameter, and the flap480is preferably accommodated in the outer sheath50.

Similar to the ligation device of the first embodiment and the second embodiment, the ligation device401of the present embodiment can smoothly perform the procedure even when a plurality of clip units are placed at narrow intervals.

In the present embodiment, the flap480does not necessarily have to be arranged over the entire circumference of the distal end member67, and may be arranged at a part in the circumferential direction.

Although each embodiment of the present invention has been described above, the technical scope of the present invention is not limited to the above-described embodiment, and it is possible to make various changes or delete some component without departing from the spirit of the present invention.

For example, as in the modified example shown inFIG. 14, the flap80may be attached to the holding tube31. Even in such a configuration, the flap can be easily stored and expanded by moving the clip10in and out of the outer sheath50.

The clip unit101including the flap80, the holding tube31, the first arm12and the second arm13can be applied to a reload unit for reloading the clip unit into the applicator after indwelling. By preparing a plurality of reload units and repeating the placement and reloading of the clip units, a plurality of clip units can be efficiently placed in the target tissue.

Any of the flaps of each of the above embodiments can be applied to the reload unit.

In the modified example shown inFIG. 15, the second sheath510is passed through the outer sheath50, and the sheath portion (not shown) and the clip10are passed through the second sheath510. The flap511is attached to the distal end of the second sheath510.

In this modification, the flap511can be moved relative to the clip unit10by operating the second sheath510. Therefore, the position of the flap511with respect to the clip10can be adjusted, and the flap511can be expanded and retracted independently of the clip10.

When the second sheath510is formed of a transparent resin, the flap511may be integrally molded with the same material.

The clip unit of the present invention is not limited to one having the above-mentioned configuration. For example, the clip unit610shown inFIG. 16may be used. The arm member611of the clip unit610includes only the first arm12, and the second arm613is fixed to the holding tube31. When the operation wire is operated to pull the arm member611into the holding tube31, the first arm12approaches the second arm613, and the tissue can be sandwiched between the first arm12and the second aim613.

When applying the present invention to the clip unit610, flaps may be provided on any of the sheath portion, the holding tube, and the second sheath.

The clip unit610is suitable for ligating tissues in a relatively narrow luminal organ such as the large intestine in a state where the wall surface of the organ and the holding tube31are substantially parallel to each other. Therefore, if the flap is provided on the plane including the first arm12and the second arm613, it may be difficult to perform the treatment or it may be difficult to suppress interference of the surrounding structures. Therefore, when the present invention is applied to the clip unit610, it is preferable to provide flaps at two positions facing each other with the axis C1of the holding tube on the plane intersecting the plane including the first arm12and the second arm613.

In the present invention, the urging means for moving the second end of the flap from the closer position to the separating position is not limited to the elastic restoring force of the flap itself. For example, a hinge may be provided at the boundary between the proximal end portion and the expansion portion, and an elastic body such as a spring may be arranged on the hinge to urge the hinge.

In each of the above embodiments and modifications, only one flap may be provided.

The treatment tool of the present invention is not limited to one provided with a clip unit at the distal end. For example, it may have a grasping forceps structure having a first arm and a second arm at the distal end portion.