JP2023135194A - Basket-type treatment instrument for endoscope - Google Patents

Abstract

To provide a basket-type treatment instrument for endoscopes eliminating deformation of a rear end face of a distal tip, preventing the distal tip from inseparably biting into a distal fitting, and allowing an operator to reuse the distal tip by separating the distal tip from the distal fitting.SOLUTION: A basket-type treatment instrument for endoscopes includes an operation wire 3 to be pushed and pulled, inserted into a flexible sheath 1 having a distal fitting 2A, and a basket part in which both ends of a plurality of basket wires 6a-6d connected to a distal end of the operation wire 3 are held by a distal tip and a rear tip. The distal fitting 2A includes: an intermediate wall part 2a having a basket wire through-hole 2i for passing the basket wires 6a-6d and whose front end face 2h serves as a distal tip contact face; and a distal tip receiving space 2b and a flexible sheath receiving space 2d that are provided on both sides of the intermediate wall part 2a. The distal tip has a cylindrical shape, a rear end side thereof is stored in the distal tip receiving space 2b, and a rear end face 7f comes into contact with the front end face 2h of the intermediate wall part 2a.SELECTED DRAWING: Figure 3

Description

The present invention relates to a basket-type endoscopic treatment instrument that is inserted into an endoscope channel and operated to move forward and backward to grasp and crush foreign objects such as stones in a body cavity.

The basket-type endoscopic treatment instrument includes a flexible sheath, an operating wire inserted into the flexible sheath so as to be freely advanced and retractable, and a distal end portion of the flexible sheath provided at the distal end of the operating wire. It also has a basket section. The basket section includes a plurality of elastic wires that bend outward, and a rear end tip and a distal tip that bring together both ends of these elastic wires, and the basket section is moved out of the flexible sheath by advancing the operation wire. When advanced, each of the plurality of elastic wires curves or bends to bulge outward, widening the distance between the wires and forming a space for capturing foreign matter, and a protruding state in which the plurality of elastic wires passes through the tip fitting and retreats into the flexible sheath. It has a function that changes to a rectilinear state when the valve is closed.

Some basket-type endoscopic treatment tools include a basket portion that captures foreign objects in a body cavity and recovers them without crushing them. This type has a function of expelling foreign matter captured by the basket portion from the body without crushing it, but it is not applicable when the foreign matter is large.

For this reason, a basket-type endoscopic treatment instrument has been proposed in which the basket portion captures foreign matter in the body cavity and further crushes the foreign matter in cooperation with a tip fitting provided at the distal end of a flexible sheath. (For example, see Patent Documents 1 and 2).

According to this type of basket-type endoscopic treatment instrument, when the plurality of elastic wires form a foreign object capturing space outside the flexible sheath and retreat into the flexible sheath from a state in which the foreign object is captured, The distal end fitting has the function of slidingly contacting and guiding the plurality of elastic wires so that the plurality of elastic wires are arranged approximately equidistantly with respect to the axis of the flexible sheath and the intervals are gradually narrowed. For this reason, the plurality of elastic wires collapse the foreign matter intake space and increase strong pressure to crush the foreign matter.

JP2013-022386A JP 2019-107183 Publication

The basket-type endoscopic treatment instrument according to Patent Document 1 is constructed by repeatedly pulling the basket wires strongly into the flexible sheath multiple times from a state in which a foreign object is taken in by a plurality of basket wires, thereby removing the basket of the distal end fitting. The gathering action on the wire allows the basket wire to clamp down on foreign objects and crush them.

However, if the outer diameter of the distal tip is smaller than the inner diameter of the distal fitting (and the inner diameter of the sheath), the force of pulling the basket wire in when the final fragmentation is performed as the foreign object progresses and becomes smaller and the trapped state is released. The intact distal tip may be drawn into the flexible sheath. If crushed calculus powder gets caught between the distal tip and the flexible sheath, resulting in a locked state, the distal tip remains in the locked state even if the operating wire is pressed. There is a problem in that the tip cannot be protruded outside the flexible sheath, making it impossible to reuse it.

The distal end fitting of the first embodiment of the basket-type endoscopic treatment instrument according to Patent Document 2 has a distal end cylindrical portion with a small inner diameter and a distal tip receiving space in the front portion, and a flexible end fitting with a large inner diameter in the rear portion. This configuration includes a rear end side cylindrical portion having a flexible sheath receiving space (FIG. 5 of Patent Document 2).

Further, the end fitting of the second embodiment has a plurality of protrusions at equal intervals on the outer periphery of the front portion for crushing foreign objects, and a basket wire guiding slit for passing one basket wire radially between each protrusion. and a rear end side cylindrical portion having a flexible sheath receiving space with a large inner diameter in the rear side portion (FIG. 7 of Patent Document 2).

In each embodiment, the tip of the flexible sheath is fitted into the flexible sheath receiving space and connected by soldering, brazing, laser welding, or the like. Furthermore, in order to prevent the distal tip from being pulled into the flexible sheath by the momentum of drawing the basket wire, the small diameter cylindrical portion on the rear end of the distal tip fits into the distal tip receiving space of the distal fitting. Further, the rear end surface of the small diameter cylindrical portion on the rear end side is configured to collide with the distal end surface of the flexible sheath and stop (FIG. 5 of Patent Document 2).

However, according to the basket-type endoscopic treatment tool according to Patent Document 2, the distal end surface of the flexible sheath has an insufficient area for receiving the rear end surface of the small diameter cylindrical portion on the rear end side of the distal tip. In addition, since the helical coil was cut, it did not have a uniform annular plane all around, so the rear end surface of the small diameter cylinder on the rear end of the distal tip collided with the distal end surface of the flexible sheath and stopped. At this time, the surface pressure becomes abnormally high in some parts, and if the basket wire is repeatedly pulled in to crush the stone, there is a risk that flare-like deformation will occur in this part. If a large flare-like deformation occurs on the rear end surface of the small-diameter cylindrical portion on the rear end of the distal tip, then the distal tip, which is in a locked state even when the operating wire is pressed, is forced to protrude out of the flexible sheath. Furthermore, even if the tip is pulled out from the endoscope channel, the tip is pinched, and separated from the tip fitting, the small-diameter cylindrical portion on the rear end of the tip cannot be smoothly inserted into the tip receiving space of the tip fitting. There is a problem that it becomes a state and cannot be reused.

The present invention was devised to solve the above-mentioned problem, and prevents the rear end surface of the distal tip from being deformed into a flare shape, thereby preventing the distal tip from digging into the distal fitting in an unseparable manner. It is an object of the present invention to provide a basket-type endoscopic treatment tool that can be reused by separating the distal tip from the distal fitting.

In order to achieve the above object, the basket type endoscopic treatment instrument according to the first aspect of the present invention includes: a long flexible sheath; a distal end fitting attached to the distal end of the flexible sheath; An operating wire that is inserted into a flexible sheath and can be moved back and forth in the axial direction within the flexible sheath by being pushed and pulled; and an operating wire that is connected to the rear end of the operating wire and that is operated by pushing and pulling. and a basket section, the basket section having a plurality of elastic basket wires connected to the tips of the operation wires, and a tip tip that holds together the tips and rear ends of these basket wires, respectively. and a rear end tip, and when the operating wire is pulled, the rear end tip and the plurality of basket wires are passed through the distal end fitting and housed in the flexible sheath, and the operating wire is pulled. When the basket wires are pushed forward from the metal tip fittings, each of the basket wires elastically returns to the outwardly expanded state to form a space for capturing foreign matter.

Furthermore, in the basket-type endoscopic treatment tool according to this aspect of the invention, the distal end fitting includes a distal tip receiving space formed in a front part, a flexible sheath receiving space formed in a rear part, The configuration includes an intermediate wall portion provided at a position sandwiched between both spaces and having a basket wire passing hole, and the distal tip is formed in a cylindrical body that binds a plurality of the basket wires, and the tip is formed in a cylindrical body that binds a plurality of the basket wires, The rear end portion is accommodated in the distal tip receiving space, and the rear end surface of the rear small diameter cylindrical portion abuts on the front end surface of the intermediate wall, which is the abutting surface for the distal tip.

In addition to the configuration of the first invention aspect, the basket-type endoscopic treatment instrument according to a second invention aspect of the present application is such that, in addition to the configuration of the first invention aspect, the distal end fitting has a cylindrical portion at a front side of the intermediate wall portion, and the cylindrical portion has a shape in which the inner surface side is the tip receiving space, and the basket wire passing hole provided in the intermediate wall has a non-circular shape having a number of basket wire guiding corners corresponding to the number of basket wires. The configuration is as follows.

In addition to the configuration of the first invention aspect, the basket-type endoscopic treatment instrument according to the third invention aspect of the present application is provided such that the distal end fitting has a plurality of protrusions on the outer periphery of the portion in front of the intermediate wall portion. , a plurality of basket wire guiding slits are alternately provided, which are gaps open between each of the protrusions and guide one of the basket wires in a protruding state in a radial direction, and the inner surfaces of the plurality of protrusions This configuration has a shape in which the side thereof serves as the distal tip receiving space.

A basket-type endoscopic treatment instrument according to a fourth aspect of the present application has, in addition to the configuration of the third aspect of the invention, the basket wire passage hole having a size through which a plurality of the basket wires can be passed, and further comprising: The structure is such that a hole wall portion at an outer position corresponding to each one of the plurality of basket wires is located near the basket wire guiding slit.

In addition to the structure of the third or fourth invention aspect, the basket-type endoscopic treatment instrument according to a fifth aspect of the invention is such that, in addition to the configuration of the third or fourth aspect of the invention, the intermediate wall portion extends from the midway position of the basket wire guiding slit to the basket wire guide slit. This configuration includes a guide groove with a semicircular cross section that is formed so as to extend to the rear end of the through hole and be cut out diagonally.

In addition to the configuration of the first invention aspect, the basket-type endoscopic treatment instrument according to a sixth aspect of the present invention has a structure in which the cylindrical body of the distal tip has a large diameter tube on the front end side and a small diameter tube on the rear end side. The folded part of the basket wire, which is formed by folding back a long wire approximately at the center, becomes the tip and is hooked inside the tip.

According to the present invention, the rear end surface of the distal tip is prevented from deforming into a flare shape, thereby preventing the distal tip from biting into the distal fitting in an irremovable manner, and separating the distal tip from the distal fitting. Accordingly, it is possible to provide a basket-type endoscopic treatment tool that can be reused.

FIG. 1 is a diagram showing the overall configuration of a basket-type endoscopic treatment tool according to an embodiment of the present invention. FIG. 2A is a diagram showing the configuration of the distal tip of the basket-type endoscopic treatment instrument according to the embodiment of the present invention and the assembly configuration of the distal tip and the basket wire, and FIG. FIG. 2(B) is a longitudinal sectional view of the distal tip, FIG. 2(B) is a longitudinal sectional view of the distal tip of the second form, FIG. 2(C) is a front view showing the assembly configuration of the distal tip and the basket wire, FIG. ) is a sectional view taken along IId-IId in FIG. 2(C), FIG. 2(E) is a sectional view taken along IIe-IIe in FIG. 2(C), and FIG. 2(F) is a sectional view taken along IIf-IIf in FIG. 2(D). A diagram showing the assembly configuration of the distal tip of the basket-type endoscopic treatment tool according to the embodiment of the present invention, the distal end fitting of the first form, and the basket wire, and the configuration of the distal fitting of the first form. 3(A) is a longitudinal sectional view when the basket wire is in a state of protruding from the tip fitting, FIG. 3(B) is a longitudinal sectional view when the tip tip and the tip fitting are fitted, and FIG. 3(C) is a perspective view of the tip fitting, FIG. 3(D) is a perspective view of a half of the tip fitting, and FIG. 3(E) is a sectional view taken along IIIe-IIIe in FIG. 3(B). A diagram showing the assembly configuration of the distal tip of the basket-type endoscopic treatment tool according to the embodiment of the present invention, the distal end fitting of the second form, and the basket wire, and the configuration of the distal end fitting of the second form. 4(A) is a longitudinal sectional view when the basket wire is in a state of protruding from the tip fitting, and FIG. 4(B) is a longitudinal sectional view when the tip tip is in a fitted state with the tip fitting. 4(C) is a perspective view of the tip fitting, FIG. 4(D) is a perspective view of a half of the tip fitting, and FIG. 4(E) is a perspective view of the tip fitting in which 2r is added to the shape of FIG. 4(C).

DESCRIPTION OF THE PREFERRED EMBODIMENTS A basket-type endoscopic treatment instrument according to an embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the direction toward the right operating section is referred to as the rear end side, or the rear, and the direction toward the left and right tip tips is referred to as the tip side, or the front.

[Basic configuration]
A basket-type endoscopic treatment instrument 100 shown in FIG. It includes an operating wire 3 inserted through the operating wire 3 so as to be freely advanced and retractable, an operating section 4 connected to the rear end of the operating wire 3 for pushing and pulling the operating wire 3, and a basket section 5. This will be explained in more detail below.

The flexible sheath 1 is, for example, a coil tube formed by closely winding a metal wire coated with fluororesin. When the flexible sheath 1 is a coiled tube, it has sufficient flexibility to allow insertion along a tortuous body cavity and a required axial tensile strength to prevent tight winding (coil pitch) from spreading. The flexible sheath 1 may be formed by winding a stainless steel thin tube into a coil, or may be formed into a flexible tube made of resin or the like and capable of being inserted into an endoscope channel. The flexible sheath 1 has, for example, an inner diameter of 1.0-5.0 mm, a coil wire diameter of 0.1-1.0 mm, and a length of 1-3 m.

The end fitting 2A or 2B is a cylindrical body made of metal, such as stainless steel, into which the basket portion 5 can be inserted and removed. The configuration of the tip metal fitting 2A or 2B will be explained in detail in the characteristic configuration described later.

The operating wire 3 is inserted into the flexible sheath 1 so as to be freely advanced and retracted, and is a twisted wire separate from the four basket wires 6a to 6d, which have flexibility, torsional rotation transmittance, and axial transmittance. Consists of lines. Note that the same material as the basket wires 6a to 6d may be used. The tip of the operating wire 3 and the rear ends of the basket wires 6a to 6d are inserted into the rear end chip 8 and connected by soldering, brazing, laser welding, or the like.

The operating section 4 includes an operating section main body 9 that is a molded body made of polycarbonate, for example, and a grip section 10 built into the rear end of the operating section main body 9. The basket part 5 provided in the is protruded and retracted from the flexible sheath 1.

The operating part main body 9 includes a chemical liquid feeding path 9a provided in alignment with the axis, a connection port 9b provided at the tip of the chemical liquid feeding path 9a and connected to the rear end of the flexible sheath 1, and a chemical liquid feeding path 9a. A drug injection port 9c is provided at the rear end side of the feeding path 9a to branch in the radial direction, and an injection device is connected to inject the drug into the flexible sheath 1. An annular sealing member 11 closes the area.

The gripping part 10 has a tip cylinder part 10a and an operating pipe 10b whose rear end is fitted and held in the tip cylinder part 10a. 9a and penetrates through the sealing member 11, so that the rear end of the operating wire 3 is fitted and held therein.

The basket portion 5 includes a plurality of elastic basket wires 6a to 6d made of twisted wires connected to the tips of the operating wires 3, and a metal basket wire that holds together the tips and rear ends of these basket wires 6a to 6d, respectively. It has a front end tip 7 and a rear end tip 8 made of metal.

The basket wires 6a to 6d preferably have a wire diameter of about 0.2 to 1.0 mm, for example, and are made of a superelastic alloy wire with very high tensile strength. Specifically, the wire is made of alloys such as nickel titanium alloy (shape memory alloy), stainless steel, gold, silver, platinum, nickel, iron, titanium, aluminum, tungsten, and the like. Note that the number of basket wires is not limited to four, and may be five or six. Furthermore, the number of basket wires may be three by devising a three-dimensional bent (curved) shape of the basket wire. can.

The basket wires 6a to 6d protrude from the flexible sheath 1 and, when no external force is applied, are given a curved or bent shape that bulges outward at equal intervals around the central axis, so that the basket wires 6a to 6d have a basket shape as a whole. In the process of being drawn into the flexible sheath 1, the foreign matter intake space 6e is gradually reduced, and the part accommodated within the flexible sheath 1 has a bent shape. It is configured to be straight.

In this embodiment, the basket wires 6a to 6d are four wires formed by folding back two elongated wires approximately at the center, and the folded portions become the tips and are tied together at the tip 7.

FIGS. 2A and 2B are diagrams showing two types of distal tips 7 that have substantially the same configuration but are manufactured differently. The distal tip 7 shown in FIG. 2(A) is a molded body in which a large diameter cylindrical portion 7a on the distal end side and a small diameter cylindrical portion 7b on the rear end side are integrated. The distal tip 7 shown in FIG. 2(B) is made by combining a large diameter cylindrical portion 7a on the distal end side having a male fitting portion and a small diameter cylindrical portion 7b on the rear end side having a female fitting portion and integrating them by laser welding or the like. It is an integrated product that is combined with the

The distal tip 7 includes a distal large-diameter cylindrical portion 7a having a rounded portion transitioning from the distal surface to the circumferential surface so as not to damage the body cavity, and a distal large-diameter cylindrical portion 7a that extends concentrically rearward from the rear end surface of the distal large-diameter cylindrical portion 7a. A large-diameter hole 7c is formed concentrically from the distal end surface of the distal-side large-diameter cylindrical section 7a, and a large-diameter hole 7c is concentrically opened from the rear end surface of the distal-side small-diameter cylindrical section 7b. A small-diameter hole 7d that is opened in and communicates with the large-diameter hole 7c and a flesh portion of the large-diameter cylindrical portion 7a on the distal end side are formed so as to pass through the diameter when viewed from the distal end side and have a depth halfway to the large-diameter hole 7c. A locking groove 7e formed in the latching groove 7e is provided.

FIGS. 2(C) to 2(F) are diagrams showing the assembly structure of the distal tip 7 and the basket wires 6a to 6d. As shown in FIG. 2(F), the folded portions of the basket wires 6a to 6d are inserted into the small diameter hole 7d and the large diameter hole 7c, and the latching pin 12 is passed through the inside, and the latching pin 12 is further hooked. By fixing both ends to the stop groove 7e, it is irremovably latched to the distal tip 7, and is also latched by the pinching pressure caused by insertion in the small diameter hole 7d.
In this embodiment, both the basket wires 6a and 6d and the folded portions of the basket wires 6c and 6d are locked by the locking pins 12, but the present invention is not limited to this, and for example, one folded portion may be locked. Instead of being locked to the pin 12, it may be fixed by the pressure of the small diameter hole 7d.

The above-mentioned latching structure between the distal tip 7, the four basket wires 6a to 6d, and the latching pin 12 prevents incarceration, and even if the distal tip 7 becomes incarcerated, it can be easily released without leaving the distal tip 7 in the body cavity. (Patent Document 2). The "incarcerated state" refers to a state in which a foreign object such as a stone that has been taken into the foreign object intake space 6e of the basket wires 6a to 6d is too large or too hard to be recovered or released. Note that the present invention also includes a case where the connection between the distal tip 7 and the four basket wires 6a to 6d is configured such that the distal end tip 7 and the four basket wires 6a to 6d cannot be released.

[Characteristic configuration]
The characteristic configuration of the mobile phone of this embodiment is that the tip fitting 2A of the first form shown in FIGS. 3(A) and (B) or the second form of the tip fitting 2A shown in FIGS. The reason is that the end fitting is 2B. The end fittings 2A, 2B are cylindrical bodies having an intermediate wall portion 2a having a basket wire passage hole 2i.

The basket wire passage hole 2i is large enough to allow the plurality of basket wires 6a to 6d to pass therethrough, and may be formed into a circular hole, but the outer portion corresponding to each of the basket wires 6a to 6d may expand in the radial direction. Preferably, it has a non-circular shape.

In the tip fitting 2A, the basket wire passage hole 2i provided in the intermediate wall portion 2a preferably has a non-circular shape having a number of basket wire guiding corners corresponding to the number of basket wires.

The tip fitting 2B has a non-circular shape in which the outer hole wall portion corresponding to each one of the plurality of basket wires 6a to 6d is located near the basket wire guide slit 2g. is preferable.

As in the illustrated example, when there are four basket wires, it is preferable that the basket wire through holes 2i have a rectangular shape. When there are five or six basket wires, it is preferable that the basket wire passing holes 2i are pentagonal or hexagonal, respectively. In this way, when the basket wire passing hole 2i has a 4-hexagonal shape, the distal tip receiving space 2b smoothly expands without causing any displacement around the axial center line of the plurality of basket wires, and also prevents the distal tip receiving space 2b from shrinking. It has a function to guide you as you go. Note that it may be a 4-hexagonal shape with rounded corners, or a star shape.

The basket wire passing hole 2i has a size that allows the rear end tip 8 and the plurality of basket wires 6a to 6d to pass smoothly when the plurality of basket wires 6a to 6d are pulled forcefully rearward.

Regarding the distal tip 7, the outer diameter of the rear end small diameter cylindrical portion 7b is such that it can be loosely fitted into the distal tip receiving space 2b of the distal cylindrical portion 2c of the distal end fitting 2A or 2B. Since the diameter of the small-diameter hole 7d of the distal tip 7 is set to a size that allows the plurality of basket wires 6a to 6d to pass through almost exactly, a large contact area of the rear end surface 7f with the front end surface 2h is ensured. There is.

The tip metal fitting 2A is a cylindrical body having an orifice-shaped intermediate wall portion 2a inside, and a portion in front of the intermediate wall portion 2a is a front tube portion 2c having a tip receiving space 2b, and a portion behind the intermediate wall portion 2a is a front tube portion 2c having a tip receiving space 2b. It has a shape in which a side portion is a rear cylindrical portion 2e having a flexible sheath receiving space 2d.

The tip fitting 2B is a cylindrical body having an orifice-shaped intermediate wall 2a inside, and the portion in front of the intermediate wall 2a is not a cylindrical portion, but has a plurality of (same number as the basket wires 6a to 6d) on the outer periphery. It has a shape in which protrusions 2f and basket wire guide slits 2g, which are gaps between the protrusions 2f, are alternately provided, and the rear part of the intermediate wall 2a has a tip receiving space 2b. It has a rear cylindrical shape.

The ultimate part of this characteristic configuration includes an intermediate wall part 2a sandwiched between a distal tip receiving space 2b formed in the front part and a flexible sheath receiving space 2d formed in the rear part, Further, the front end surface 2h on the distal side of the intermediate wall portion 2a comes into contact to stop the distal tip 7 from entering the distal tip receiving space 2b when the plurality of basket wires 6a to 6d are forcefully pulled backward. By setting the difference between the inner diameter of the distal tip receiving space 2b and the size of the basket wire through hole 2i formed in the intermediate wall portion 2a as required, the front end surface, which is the abutting surface for the distal tip, is formed. This is because the area of 2h is kept large.

This will be explained in more detail below.
Both the distal end fitting 2A and the distal end fitting 2B must have a distal tip receiving space 2b formed in the front portion and a flexible sheath receiving space 2d formed in the rear portion. Regarding the size of the inner diameter of the distal tip receiving space 2b and the inner diameter of the flexible sheath receiving space 2d, the former is smaller, but it is not an essential component.

FIGS. 3(A) to 3(E) show a first form of the tip fitting 2A. This tip fitting 2A is a simple front tube including a front tube portion 2c, a rear tube portion 2e, and an intermediate wall portion 2a having a basket wire through hole 2i, and having the intermediate wall portion 2a and a tip receiving space 2b. The distal end portion of the portion 2c is provided with tapered portions 2j and 2k on the inner and outer surfaces.

The front cylindrical portion 2c defines a tip receiving space 2b. The tip end side of the tip receiving space 2b has an inner taper part 2j having a taper angle (intersection angle) of, for example, 60 degrees so as to be largely chamfered, and the plurality of basket wires 6a to 6d are forcefully moved backward. It has a function of guiding the distal tip 7 to the distal tip receiving space 2b when pulled, and also a function of guiding the basket wires 6a-6d without squeezing them when the basket wires 6a-6d are extended and retracted. have The tapered portion 2k on the outer surface side is provided to prevent damage to the body cavity and the inside of the endoscope channel when entering the body cavity. Note that the front cylindrical portion 2c has tapered portions 2j and 2k formed at its distal end so that it is sharp and has an enhanced function of crushing foreign matter.

FIGS. 4(A) to 4(E) show a second form of the tip fitting 2B. As shown in FIGS. 4(C) and 4(D), the front portion of the tip fittings 2B is not a simple cylinder, but has a plurality of (four) pieces arranged equidistantly in the circumferential direction so as to surround the tip receiving space 2b. This configuration includes a protrusion 2f. The inner surfaces 2n of the plurality of protrusions 2f are formed in a concave cylindrical shape that becomes a part of the tip receiving space 2b, which is a cylindrical space, and a tapered portion 2m is formed at the tip of the inner surface 2n. ing. Thereby, the plurality of protrusions 2f equally arranged in the circumferential direction have the function of guiding and holding the distal tip 7 to the distal tip receiving space 2b. Further, the plurality of projections 2f also have tapered portions 2p and 2q at other corner portions. The slightly sharp tips of the plurality of protrusions 2f equally spaced in the circumferential direction have a higher ability to crush foreign objects than the tip fitting 2A.

The basket wire guiding slit 2g between the protrusions 2f of the metal tip 2B has the function of guiding one of the basket wires 6a to 6d protruding from the metal tip 2B in four radial directions.

Further, as shown in FIG. 4(E), the intermediate wall portion 2a has a cross section formed so as to extend from the midway position of the basket wire guide slit 2g to the rear end of the basket wire passage hole 2i. It is provided with a semi-circular guide groove 2r. By providing this guide groove 2r, the passage between the basket wire guide slit 2g and the basket wire passing hole 2i of the basket wires 6a to 6d becomes smooth, and the resistance when pushing and pulling the basket wires 6a to 6d is reduced. The basket wires 6a to 6d are smoothly guided between the front cylinder part 2c and the inner space of the flexible sheath 1, and the basket wires 6a to 6d are squeezed at the corners during retraction, causing damage and breakage. It can reduce fear.

Further, the axial length L2 of the distal tip receiving space 2b is set shorter than the length L1 of the rear small diameter cylindrical portion 7b of the distal tip 7. The end surface (stepped portion) is configured so as not to come into contact with the tip surface of the protrusion 2f of the tip metal fitting 2B.

Explain the effects in relation to the treatment.
When treating a foreign object within a body cavity (for example, the papilla of the duodenum), the endoscopic treatment instrument 100 is inserted into an endoscope channel together with a guide wire. When it is confirmed under fluoroscopy that the opening at the distal end of the insertion section of the endoscope corresponds to the entrance of the body cavity, the tip of the guide wire further protrudes from the opening at the distal end of the insertion section of the endoscope and enters the body cavity. The endoscope treatment instrument 100 is inserted to a position beyond the affected area to be treated, and is then positioned within the endoscope channel, which includes the distal tip 7 and the distal fitting 2A (or 2B). The distal end portion of the flexible sheath 1 is inserted into the body cavity to a position beyond the affected area to be treated, as the flexible sheath 1 is engaged and guided by the guide wire.

Next, with the flexible sheath 1 not moving, the basket portion 5 inside the flexible sheath 1 is advanced beyond the tip fitting 2A (or 2B), so that the basket wires 6a to 6d are moved outward, respectively. The foreign matter intake space 6e is formed by bending or curving and widening the interval.

Next, by retracting the flexible sheath 1 and the operating wire 3 together, when the distal end fitting 2A (or 2B) is placed in a position retracted from the affected area to be treated, the foreign matter intake space 6e of the basket wires 6a to 6d is removed. corresponds to foreign matter. Here, by finely moving the operating wire 3 back and forth, the foreign matter can be taken into the foreign matter taking-in spaces 6e of the basket wires 6a to 6d.

Next, by holding the flexible sheath 1 in an immovable state and retracting the operating wire 3, the basket wires 6a to 6d are retired from the tip fitting 2 into the flexible sheath 1, and at this time, The distance between the basket wires 6a to 6d is narrowed, thereby narrowing the foreign matter intake space 6e to trap the foreign matter, further increasing strong pressure, and further colliding the foreign matter against the tip fitting 2A (or 2B) to crush it.

The function of crushing foreign matter by the tip of the front cylinder part 2c of the tip fitting 2A shown in FIGS. 3(A) and (B), and the plurality of projections 2f of the tip fitting 2B shown in FIGS. 4(A) and (B) This is different from the function of the tip of the blade to crush foreign objects.

In the case of the tip metal fitting 2A, the function of crushing foreign matter by the tip of the front cylindrical portion 2c and the plurality of basket wires 6a to 6d is as follows. After the foreign matter has been taken into the foreign matter intake spaces 6e of the plurality of basket wires 6a to 6d, by pulling the operating wire 3, the rear end tip 8 is drawn into the distal tip receiving space 2b, and then the plurality of basket wires As the wires 6a to 6d are drawn in, the foreign matter intake space 6e is reduced, and the plurality of basket wires 6a to 6d gradually tighten the foreign matter, causing the foreign matter to impact the tip of the front cylinder portion 2c. be forced to. By pushing and pulling the operating wire 3 a plurality of times, the foreign matter is further crushed.

In the case of the tip fitting 2B, the function of crushing foreign matter by the tips of the plurality of protrusions 2f and the plurality of basket wires 6a to 6d is as follows. By pulling the operating wire 3 from a state in which foreign matter has been taken into the foreign matter intake space 6e of the plurality of basket wires 6a to 6d, the plurality of basket wires 6a to 6d pass through the basket wire guide slit 2g and move into the intermediate wall portion 2a. The basket wire is drawn into the flexible sheath 1 through the basket wire passage hole 2i provided in the basket wire passage hole 2i. Then, the basket portion 2 reduces the foreign object intake space 6e and tightens the foreign object, and the foreign object is impulsively pressed against the tips of the plurality of protrusions 2f. By pushing and pulling the operating wire 3 a plurality of times, the foreign matter is further crushed.

In both the case of the tip fitting 2A and the tip fitting 2B, when the plurality of basket wires 6a to 6d are vigorously pulled backward each time, the tip tip 7 is smoothly drawn into the tip receiving space 2b, and the tip tip 7 is drawn smoothly into the tip receiving space 2b. The rear end surface 7f of the tip 7 contacts the front end surface 2h of the intermediate wall 2a to stop the tip 7 from entering. The foreign matter that is crushed and enters the distal tip receiving space 2b is strongly pressed by the rear end surface 7f of the distal tip 7 and the front end surface 2h of the intermediate wall portion 2a, and is further crushed into smaller pieces. In the contact between the rear end surface of the distal tip 7 and the front end surface 2h of the intermediate wall portion 2a of the distal end fitting 2A or 2B, the rear end surface of the distal tip 7 is approximately annular, and the front end surface 2h is shaped around the central axis. Since it has a sufficiently large area that is approximately equally distributed, the surface pressure at the time of contact does not become maximum and the rear end surface of the tip tip 7 does not deform into a flare shape. This prevents the tip from biting into the tip fitting 2A or 2B irreparably, and the tip 7 can be separated from the tip fitting 2A or 2B and reused.

In addition, in the tip metal fitting 2B having a shape in which the front part has a plurality of protrusions 2f divided in the circumferential direction, the area of the tip surface of the protrusions 2f is small, so if it collides with the stepped surface of the hard tip 7, it will deform. However, in the present application, the rear end surface 7f of the distal tip 7 is connected to the front end surface 2h of the intermediate wall 2a. Since the configuration is such that when they come into contact and stop the advance of the tip 7, the stepped surface of the large diameter cylindrical portion 7a on the tip side of the tip 7 and the tip surface of the protrusion 2f of the tip fitting 2B are separated by a large distance. Since they do not collide, there is no fear that the protrusion 2f will be deformed, and smooth fitting and disassembly between the tip 7 and the metal fitting 2B is ensured.

As described above, according to the basket-type endoscopic treatment instrument according to the present invention, the distal end fitting is located in the basket at a position sandwiched between the distal tip receiving space and the flexible sheath receiving space. An intermediate wall portion having a wire passage hole and a front end surface of which functions as a contact surface for the distal tip, the distal tip being formed into a cylindrical body, and the rear end side portion of the distal tip fitting being in the distal tip receiving space of the distal fitting. The structure is such that the rear end surface of the small diameter cylindrical portion on the rear end side comes into contact with the front end surface of the intermediate wall portion of the tip fitting, and when the rear end surface of the tip tip and the front end surface of the intermediate wall portion of the tip fitting come into contact with each other. Since a sufficient area is secured and the surface pressure at the time of contact is distributed approximately evenly around the axis center line, the rear end surface of the tip tip does not deform into a flare shape, and the tip This prevents the tip from irreparably digging into the tip fitting, and allows the tip to be separated from the tip fitting and reused.

100...Basket type endoscope treatment tool 1...Flexible sheath 2A...Tip metal fitting 2B...Tip metal fitting 2a...Intermediate wall portion 2b...Tip tip receiving space 2c...Front side cylinder part 2d...Flexible sheath receiving space 2e... Rear cylindrical portion 2f...Protrusion 2g...Slit for guiding basket wire 2h...Front end surface (abutment surface against tip tip)
2i...Basket wire through hole 2j, 2k, 2m, 2p, 2q...Tapered part 2n...Inner surface 2r...Guide groove 3...Operation wire 4...Operation part 5...Basket part 6a-6d...Basket wire 6e...Foreign matter intake space 7... Tip tip 7a...Large diameter cylindrical part on the tip side 7b...Small diameter cylindrical part on the rear end side 7c...Large diameter hole part 7d...Small diameter hole part 7e...Latching groove 7f...Rear end face 8...Rear end tip 9...Operation section main body 9a... Chemical solution feeding path 9b...Connection port 9c...Medicine inlet 10...Gripping part 10a...Tip cylinder part 10b...Operation pipe 11...Seal member 12...Latching pin

Claims (6)

a long flexible sheath;
a tip fitting attached to the tip of the flexible sheath;
an operating wire that is inserted into the flexible sheath and can be moved back and forth in the axial direction within the flexible sheath by being pushed and pulled;
an operating section connected to the rear end of the operating wire for pushing and pulling the operating wire; a plurality of basket wires having elasticity connected to the distal end of the operating wire; and a distal end and a rear end of the basket wires, respectively. The device has a distal tip and a rear end tip that are held together, and when the operation wire is pulled, the rear end tip and the plurality of basket wires are passed through the distal end fitting and housed in the flexible sheath. and a basket having a function of forming a space for taking in foreign matter by elastically returning each of the basket wires to an outwardly expanded state when the operation wires are pushed forward and protrude from the end fittings. Department and
In a basket-type endoscopic treatment instrument equipped with
The tip metal fitting is
A configuration including a distal tip receiving space formed in the front part, a flexible sheath receiving space formed in the rear part, and an intermediate wall part provided between both spaces and having a basket wire passage hole. and
The distal tip is
A cylindrical body is formed to bind a plurality of the basket wires, and a rear end portion of the cylindrical body is accommodated in the tip receiving space, and a rear end surface of the rear small diameter cylindrical portion is connected to the intermediate wall portion. 1. A basket-type endoscopic treatment instrument, characterized in that it is configured to abut against a front end surface of the basket-type endoscope, which is a contact surface for a distal tip. The tip metal fitting is
A portion in front of the intermediate wall portion is a cylindrical portion, and an inner surface of the cylindrical portion is the distal tip receiving space,
The inside of the basket mold according to claim 1, wherein the basket wire passing hole provided in the intermediate wall has a non-circular shape having a number of basket wire guiding corners corresponding to the number of basket wires. Endoscopy treatment equipment. The tip metal fitting is
A plurality of protrusions are provided on the outer periphery of a portion in front of the intermediate wall, and a plurality of baskets are provided in gaps between the protrusions and guide the one basket wire in a protruding state in a radial direction. 2. The basket-type endoscope treatment instrument according to claim 1, wherein the basket-type endoscopic treatment instrument has a shape in which wire guiding slits are provided alternately, and the inner surface of the plurality of protrusions serves as the distal tip receiving space. The basket wire passing hole has a size that allows the plurality of basket wires to pass through, and further, a hole wall portion at an outer position corresponding to each one of the plurality of basket wires is in the vicinity of the basket wire guiding slit. 4. The basket-type endoscopic treatment instrument according to claim 3, wherein the basket-type endoscopic treatment instrument is provided so as to be positioned. The intermediate wall portion is provided with a guide groove having a semicircular cross section that is cut out diagonally from the midway position of the basket wire guide slit to the rear end of the basket wire passage hole. The basket-type endoscopic treatment instrument according to claim 3 or 4. The cylindrical body of the distal tip has a shape including a large-diameter cylindrical portion on the front end side and a small-diameter cylindrical portion on the rear end side, and the folded part of the basket wire, which is formed by folding back a long wire approximately at the center, becomes the tip and the tip ends. The basket-type endoscopic treatment tool according to claim 1, wherein the treatment tool is configured to be hooked inside a tip.

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