JP2001070314A - Snare for endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To insert smoothly a snare loop into the base end of a sheath at the time of reassembly after cleansing and sterilization by rebending the forward end of the snare loop at a curvature making the outside diameter smaller than the bore of a base end insertion member and making the inside diameter equal to or larger than the diameter of an elastic wire. SOLUTION: A snare loop 3 made of an elastic wire is connected to the tip of an operating wire 2 passed into a flexible sheath 1 in a manner that allows it to be advanced and withdrawn freely, which is inserted into and removed from the treatment device insertion channel of an endoscope made of an electrically insulating tetrafluoroethylene tube or the like, through a connecting pipe 4. The forward end 3a of this snare loop 3 is formed by rebending at a curvature making the diameter of the outside 3 smaller than the base end insertion member 14, and making the diameter of the inside equal to or larger than the diameter of an elastic wire forming the snare loop 3, whereby at the time of assembly after cleansing and sterilization or the like, the insertion of the snare loop 3 from the tip side to the hole of the base end insertion member 14 is smoothened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a snare for an endoscope used to cut a polyp through a treatment tool insertion channel of an endoscope.

[0002]

2. Description of the Related Art Generally, an endoscope snare has an operation wire inserted and arranged in a flexible sheath so as to be able to advance and retreat in an axial direction.
A snare loop made of an elastic wire is connected to the distal end of the operation wire, and the snare loop moves in and out of the distal end of the flexible sheath by moving the operation wire in and out in the axial direction. Swells by its own elasticity and contracts by being drawn into the flexible sheath.

FIG. 5 shows such a conventional snare for an endoscope. When cleaning and disinfecting after use, a unit in which an operation wire 91 and a snare loop 92 are integrally connected is flexible. It can be withdrawn from the sheath 93. At the tip 92a of the snare loop 92, the elastic wire is bent back into a small U-shape.

When the endoscope snare is to be reused after cleaning and disinfection, the snare loop 92 is inserted from the distal end into proximal insertion members 94 and 95 disposed at the proximal end of the flexible sheath 93, and the snare loop 92 can be used as it is. It is designed to be pushed into the flexible sheath 93 and assembled.

[0005]

FIG. 6 shows a state in which the snare loop 92 is inserted into the proximal insertion members 94 and 95.
4 and 95, the bent back portion 92a of the snare loop 92 is inserted into the proximal insertion members 94 and 95.
In many cases, the wire of the elastic wire forming the snare loop 92 is frayed and damaged due to the rubbing on the inner surface of the hole.

Accordingly, the present invention provides an endoscope which can be easily assembled by smoothly inserting a snare loop into a proximal insertion member arranged at the proximal end of a sheath at the time of reassembly after cleaning and disinfection. The purpose is to provide a snare.

[0007]

In order to achieve the above object, an endoscope snare according to the present invention has an operating wire inserted and arranged in a sheath so as to be able to advance and retreat in the axial direction, and a single elastic wire is provided. The snare loop formed by bending is connected to the tip of the operation wire, and the snare loop moves in and out of the tip of the flexible sheath by operating the operation wire in the axial direction,
A snare for an endoscope in which a snare loop is expanded by its own elasticity outside a flexible sheath and contracts by being pulled into the flexible sheath, and a proximal insertion connected to a proximal end of the sheath. In a configuration in which the snare loop is inserted from the distal end into the hole of the member, the distal end portion of the snare loop is formed such that the diameter of the outer surface is smaller than the diameter of the hole of the proximal insertion member, and the diameter of the inner surface is greater than the diameter of the elastic wire. It is bent back with a curve of size.

[0008] The tip of the snare loop may be bent back into a rounded V-shape, in other words, it may be bent back into a substantially U-shape.

[0009]

Embodiments of the present invention will be described with reference to the drawings. FIG. 2 shows a snare for an endoscope according to an embodiment of the present invention. Reference numeral 1 denotes a flexible sheath made of, for example, an electrically insulating tube made of tetrafluoroethylene resin, which is not shown. It is inserted into and removed from the treatment instrument insertion channel of the endoscope.

An operation wire 2 made of a flexible conductive metal is inserted through the entire length of the flexible sheath 1 so as to be able to advance and retreat in the axial direction. It is arbitrarily advanced and retracted from the right side in FIG. 2).

A snare loop 3 made of a conductive elastic wire is connected to a distal end portion of the operation wire 2 via a connection pipe 4. However, the operation wire 2 may be formed by extending the snare loop 3.

The elastic wire forming the snare loop 3
It is formed of a stranded stainless steel wire (for example, a 1 × 19 twisted wire of 0.3 mm in which 19 strands of 0.06 mm in diameter are twisted), and in a state where no external force is applied, FIG. As shown in FIG. 2, a loop extending several centimeters is formed, and can be narrowed by elastic deformation by applying an external force.

Therefore, when the operation wire 2 is advanced and retracted from the proximal end side, the snare loop 3 moves in and out of the distal end of the flexible sheath 1, and the snare loop 3 is shown in FIG. It expands in a loop by its own elasticity, and contracts by being drawn into the flexible sheath 1.

A proximal end cap 10 is connected to the proximal end of the flexible sheath 1. The proximal end portion of the operation wire 2 is connected to a stainless rod 20 extending from the inside of the flexible sheath 1 to the proximal end through the proximal end cap 10. On the side of the base end 10, an injection tube receiving base 11 communicating with the inside of the flexible sheath 1 is provided in a protruding manner.

FIG. 3 shows the vicinity of the base end base 10 with the operation wire 2 pulled out, for example, during cleaning and disinfection after using the snare for an endoscope. The proximal end is pressed and fixed to the distal end portion of the proximal base 10 by a holding screw 12 screwed into the proximal end base 10. 13 is
It is a buckling prevention tube.

On the other end side of the base end cap 10, a base end insertion tube 14 protrudes from an extension of the axis of the flexible sheath 1. The base insertion tube 14 is attached to the base base 10 by screwing the base end insertion tube 15 integrally fixedly connected to the base base 10.
By adjusting the screwing amount of the O-ring, the crushing amount of the sealing O-ring 16 can be adjusted.

Therefore, the base insertion tube 14 and the base insertion screw tube 15 may be originally formed as a single part, and the base insertion tube 14 and the base insertion screw tube 15 are formed by the base end of the present invention. Corresponds to the insertion member. However, if the O-ring 16 is not provided, the base cap 10 itself may be used as the base insertion member.

These base end cap 10 and base end insertion screw cylinder 1
5 and the proximal end insertion tube 14 are formed with through-holes having substantially the same size as the inner diameter of the flexible sheath 1 at positions directly communicating with the flexible sheath 1.
Passes.

FIG. 4 is an enlarged view of a portion of the snare loop 3. The tip portion 3a is bent back into a substantially U-shape and gradually widens rearward. It can be said that it is bent back into a shape. However, it may be U-shaped or the like.

The tip 3a of the snare loop 3 is
the diameter of ao is smaller than the hole diameter of the proximal insertion members 14 and 15;
In addition, the diameter of the inner surface 3ai is bent back with a curve that is equal to or larger than the diameter of the elastic wire forming the snare loop 3.

As described above, the tip portion 3a of the snare loop 3
The diameter of the outer surface 3ao is smaller than the hole diameter of the proximal insertion members 14 and 15, so that the snare loop 3 is moved to the distal end side for assembly after cleaning and disinfection is completed, as shown in FIG. When the snare loop 3 is inserted into the holes of the proximal insertion members 14 and 15 from above, the distal end portion 3a is smoothly inserted without being caught by the hole wall surfaces of the proximal insertion members 14 and 15.

Further, since the diameter of the inner surface 3ai of the tip portion 3a of the snare loop 3 is formed to be larger than the diameter of the elastic wire forming the snare loop 3, the tip portion 3a
At a, the snare loop 3 is not bent sharply, and there is no durable problem such as a broken wire.

[0023]

According to the present invention, the tip portion of the snare loop is bent back with a curve whose outer surface diameter is smaller than the hole diameter of the proximal insertion member and whose inner surface diameter is larger than the elastic wire diameter. As a result, when reassembling after cleaning and disinfection, the snare loop can be smoothly inserted into the proximal insertion member located at the proximal end of the sheath without causing durable problems such as wire breakage, facilitating assembly. It can be performed.

[Brief description of the drawings]

FIG. 1 is a partially enlarged side cross-sectional view when an endoscope snare according to an embodiment of the present invention is assembled.

FIG. 2 is a side view of the endoscope snare according to the embodiment of the present invention.

FIG. 3 is a side sectional view of a proximal portion of a sheath of the endoscope snare according to the embodiment of the present invention.

FIG. 4 is an enlarged side view of a distal end portion of the endoscope snare according to the embodiment of the present invention.

FIG. 5 is a side view of a conventional endoscope snare.

FIG. 6 is a partially enlarged side sectional view of a conventional endoscope snare when it is assembled.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flexible sheath 2 Operation wire 3 Snare loop 3a Tip part 10 Base end cap 14 Base end insertion tube (base end insertion member) 15 Base end insertion screw tube (base end insertion member)

Claims (3)

[Claims] An operating wire is inserted and arranged in a sheath so as to be able to advance and retreat in an axial direction, a snare loop formed by bending one elastic wire is connected to a tip of the operating wire, and the operating wire is connected in the axial direction. The snare loop moves in and out of the distal end of the flexible sheath by operating forward and backward, and the snare loop expands by its own elasticity outside the flexible sheath and is drawn into the flexible sheath. A snare for an endoscope which is narrowed by a snare loop, wherein the snare loop is inserted from a distal end into a hole of a proximal insertion member connected to a proximal end of the sheath and assembled. Characterized in that the diameter of the outer surface is smaller than the hole diameter of the proximal insertion member, and the diameter of the inner surface is bent back to a size larger than the diameter of the elastic wire. Endoscope snare. 2. A snare for an endoscope according to claim 1, wherein the tip of said snare loop is bent back into a rounded V-shape. 3. The endoscope snare according to claim 1, wherein a tip portion of the snare loop is bent back into a substantially U-shape.