JP4495276B2 - Endoscope snare - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope snare that is used to cut a polyp through a treatment instrument insertion channel of an endoscope.
[0002]
[Prior art]
In general, a snare for an endoscope has an operation wire inserted through a flexible sheath so as to be movable back and forth in the axial direction, a snare loop made of an elastic wire is connected to the tip of the operation wire, and the operation wire is moved in the axial direction. The snare loop moves in and out of the distal end of the flexible sheath by advancing and retracting, and the snare loop swells by its own elasticity outside the flexible sheath and becomes constricted by being pulled into the flexible sheath. ing.
[0003]
FIG. 5 shows such a conventional endoscopic snare. At the time of cleaning and disinfection after use, a unit in which the operation wire 91 and the snare loop 92 are integrally connected is connected to the flexible sheath 93. It can be removed from. At the tip end portion 92a of the snare loop 92, the elastic wire is bent back into a small U shape.
[0004]
When the snare for the endoscope is used again after cleaning and disinfection, the snare loop 92 is inserted from the distal end into the proximal end insertion members 94 and 95 disposed at the proximal end of the flexible sheath 93, and the flexible sheath is left as it is. It is designed to be pushed into 93 and assembled.
[0005]
[Problems to be solved by the invention]
FIG. 6 shows a state in which the snare loop 92 is inserted into the proximal end insertion members 94, 95. The snare loop 92 is narrowed and pushed into the proximal end insertion members 94, 95. There are many cases where the bent end portion 92a of the snare loop 92 is rubbed against the inner surface of the hole of the base end insertion member 94, 95 and the strand of the elastic wire forming the snare loop 92 is frayed and damaged. .
[0006]
Therefore, the present invention provides an endoscope snare that can be easily assembled by smoothly inserting a snare loop into a proximal end insertion member disposed at the proximal end of a sheath at the time of reassembly after cleaning and disinfection. The purpose is to provide.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an endoscope snare according to the present invention has a snare loop formed by inserting and arranging an operation wire in a sheath so as to be movable forward and backward in the axial direction, and bending one elastic wire. The snare loop enters and exits the distal end of the flexible sheath by operating the operation wire in the axial direction, and the snare loop is swollen by its own elasticity outside the flexible sheath. An endoscopic snare that is narrowed by being pulled into the sheath and assembled by inserting a snare loop from the distal end into the hole of the proximal end insertion member connected to the proximal end of the sheath. 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 diameter of the elastic wire.
[0008]
Note that the tip portion of the snare loop may be bent back into a rounded V-shape, and in short, it may be bent back into a substantially U-shape.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 2 shows an endoscopic snare according to an embodiment of the present invention. Reference numeral 1 denotes a flexible sheath made of, for example, an electrically insulating tetrafluoroethylene resin tube, which is not shown. It is inserted into and removed from the treatment instrument insertion channel of the endoscope.
[0010]
A flexible conductive metal operation wire 2 is inserted through the entire length of the flexible sheath 1 so as to be able to advance and retract in the axial direction over the entire length thereof. Advancing / retreating is arbitrarily performed from the right).
[0011]
A snare loop 3 made of a conductive elastic wire is connected to the 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.
[0012]
The elastic wire forming the snare loop 3 is formed by a stranded wire of stainless steel wire (for example, a 1 × 19 stranded wire having a diameter of 0.3 mm obtained by twisting 19 strands having a diameter of 0.06 mm). In a state where no is applied, a loop having a spread of several centimeters is formed as shown in FIG. 2, and it can be elastically deformed and constricted by applying an external force.
[0013]
Therefore, when the operation wire 2 is advanced and retracted from the proximal end side, the snare loop 3 enters and exits the distal end of the flexible sheath 1, and the snare loop 3 is outside the flexible sheath 1 as shown in FIG. It swells in a loop shape due to its own elasticity, and is narrowed by being drawn into the flexible sheath 1.
[0014]
A proximal end cap 10 is connected to the proximal end of the flexible sheath 1. Further, the proximal end portion of the operation wire 2 is connected to a stainless rod 20 extending from the flexible sheath 1 through the proximal end cap 10 to the proximal side. At the side portion of the base end cap 10, a syringe barrel receiving cap 11 that projects into the flexible sheath 1 is projected.
[0015]
FIG. 3 shows the vicinity of the base end cap 10 in a state where the operation wire 2 has been removed during cleaning and disinfection after using the endoscope snare, and the base end of the flexible sheath 1 is shown in FIG. The base end cap 10 is pressed and fixed to the distal end portion of the base end cap 10 by a holding screw 12 screwed into the base end cap 10. Reference numeral 13 denotes a bend preventing tube.
[0016]
On the other end side of the base end cap 10, a base end insertion cylinder 14 projects from the extension line of the axis of the flexible sheath 1. The base end insertion tube 14 is attached to the base end cap 10 by screwing a base end insertion screw tube 15 fixedly connected together into the base end cap 10, and the screwing amount of the base end insertion screw tube 15 is adjusted. By doing so, the crushing amount of the sealing O-ring 16 can be adjusted.
[0017]
Therefore, the base end insertion tube 14 and the base end insertion screw tube 15 may be originally formed as one component, and the base end insertion tube 14 and the base end insertion screw tube 15 are the base end insertion member of the present invention. Applicable. However, if the O-ring 16 is not provided, the base end cap 10 itself may be a base end insertion member.
[0018]
In the base end cap 10, the base end insertion screw cylinder 15, and the base end insertion cylinder 14, a through hole having substantially the same size as the inner diameter of the flexible sheath 1 is formed at a position that communicates with the flexible sheath 1 in a straight line. Then, the operation wire 2 passes through them.
[0019]
FIG. 4 shows an enlarged portion of the snare loop 3, and the tip portion 3a is bent back in a substantially U shape and gradually spreads backward, so that it is bent into a rounded V shape. It can be said that it has been returned. However, it may be U-shaped.
[0020]
The distal end portion 3 a of the snare loop 3 is bent with a curve whose outer surface 3 ao is smaller in diameter than the hole diameters of the proximal insertion members 14 and 15 and whose inner surface 3 ai is larger than the diameter of the elastic wire forming the snare loop 3. It has been returned.
[0021]
Since the diameter of the outer surface 3ao of the distal end portion 3a of the snare loop 3 is formed smaller than the hole diameter of the base end insertion members 14 and 15, as shown in FIG. When the snare loop 3 is inserted into the holes of the proximal insertion members 14 and 15 from the distal end side thereof, the distal portion 3a is brought into contact with the hole wall surfaces of the proximal insertion members 14 and 15 when the snare loop 3 is narrowed. Inserts smoothly without being caught.
[0022]
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 snare loop 3 is not suddenly bent at the tip portion 3a. , Durability problems such as wire breakage do not occur.
[0023]
【The invention's effect】
According to the present invention, the distal 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 equal to or larger than the diameter of the elastic wire. When reassembling later, the snare loop can be smoothly inserted into the proximal end insertion member arranged at the proximal end of the sheath without causing any durability problems such as wire breakage. .
[Brief description of the drawings]
FIG. 1 is a partially enlarged side cross-sectional view of an endoscope snare according to an embodiment of the present invention when 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 end side portion of the sheath of the endoscope snare according to the embodiment of the present invention.
FIG. 4 is an enlarged side view of the distal end portion of the endoscope snare according to the embodiment of the present invention.
FIG. 5 is a side view of a conventional endoscopic snare.
FIG. 6 is a partially enlarged side cross-sectional view when assembling a conventional endoscope snare.
[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 cylinder (base end insertion member)
15 Base end insertion screw cylinder (base end insertion member)

Claims (3)

An operation wire is inserted and arranged in the flexible sheath so as to be able to advance and retract in the axial direction, a snare loop formed by bending one elastic wire is connected to the tip of the operation wire, and the operation wire is advanced and retracted in the axial direction. By operating, the snare loop enters and exits into the distal end of the flexible sheath, and the snare loop swells by its own elasticity outside the flexible sheath and is retracted by being pulled into the flexible sheath. In an endoscopic snare,
By screwing and attaching a base end insertion member formed with a through hole that leads straight to the flexible sheath to the base end cap connected to the base end of the flexible sheath, and adjusting the screwing amount, While being configured to be able to adjust the crushing amount of the sealing O-ring arranged in a state of being sandwiched between the base end cap side and the base end insertion member side,
The length of the through hole formed in the proximal end insertion member is longer than the length of the snare loop in the constricted state , and the distal end portion of the snare loop has an outer surface diameter penetrating the proximal end insertion member. An endoscopic snare characterized by being bent back by a curve having a diameter smaller than the diameter of the hole and having an inner diameter equal to or larger than the diameter of the elastic wire. The snare for an endoscope according to claim 1, wherein a tip portion of the snare loop is bent back into a rounded V shape. The snare for an endoscope according to claim 1, wherein a tip portion of the snare loop is bent back into a substantially U shape.

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