JP4554796B2 - Endoscopic high frequency snare - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope high-frequency snare that is used to cut a polyp through a treatment instrument insertion channel of an endoscope.
[0002]
[Prior art]
In general, a high-frequency snare for an endoscope has an operation wire inserted and disposed in a flexible sheath so as to be movable back and forth in the axial direction, and a snare loop formed of a conductive elastic wire is connected to the distal end of the operation wire. The snare loop is configured so that a high-frequency current can be applied, and the snare loop moves in and out of the distal end of the flexible sheath by operating the operation wire in the axial direction. It swells due to elasticity and is squeezed by being drawn into the flexible sheath.
[0003]
In use, by pulling the operation wire after the polyp is surrounded by the snare loop, the polyp 100 is bound by the snare loop 10 as shown in FIG. The polyp 100 is cauterized and cut.
[0004]
[Problems to be solved by the invention]
As described above, by applying a high-frequency current to the snare loop 10, a portion of the human tissue in contact with the snare loop 10 is cut without bleeding while being solidified by Joule heat.
[0005]
However, when the human tissue in contact with the snare loop 10 is heated and solidified in this way, a considerable portion of the section tissue of the polyp 100 is destroyed by heat (thermal destruction part A), and the recovered polyp 100 cancer In some cases, tissue examination or the like cannot be performed accurately.
[0006]
Therefore, an object of the present invention is to provide a high-frequency snare for an endoscope that can cut a polyp or the like without bleeding by energizing a high-frequency current and that the section tissue is not easily destroyed by heat.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an endoscope high-frequency snare according to the present invention includes a snare loop formed of a conductive elastic wire by inserting an operation wire through a flexible sheath so as to advance and retract in the axial direction. Is connected to the tip of the operation wire, and a high-frequency current can be applied to the snare loop, and by moving the operation wire forward and backward in the axial direction, the snare loop enters and exits the tip of the flexible sheath. One of the front and back surfaces of the snare loop in the vicinity of the tip of the snare loop, in which the loop is swollen by its own elasticity outside the flexible sheath and is narrowed by being pulled into the flexible sheath Are formed of an electrically insulating material or a defective conductive material.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 2 shows an endoscopic high-frequency 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.
[0009]
A flexible conductive metal operation wire 2 is inserted through the entire length of the flexible sheath 1 so as to be movable back and forth in the axial direction, and can be freely advanced and retracted from the proximal end side by an operation portion not shown. Operated.
[0010]
A snare loop 10 formed by bending a single conductive elastic wire 11 into a loop shape is connected to the distal end portion of the operation wire 2 via a connection pipe 3, and the snare loop is connected via the operation wire 2. 10 can be energized with a high-frequency current.
[0011]
However, the snare loop 10 may be formed by connecting two elastic wires 11 at the tip, and the operation wire 2 may be formed by extending the elastic wire 11. As the elastic wire 11, for example, a stainless steel wire or a stranded wire is used.
[0012]
In the state where no external force is applied, the snare loop 10 forms a loop having a spread of several centimeters as shown in FIG. 2 due to the elasticity of the elastic wire 11, and the operation wire 2 is pulled toward the hand side. Then, the snare loop 10 is drawn into the flexible sheath 1 and is elastically deformed to be narrowed.
[0013]
FIG. 1 shows a state in which the snare loop 10 is partially pulled into the flexible sheath 1, and only one of the front and back surfaces of the snare loop 10 is coated with an electrical insulating material or a defective conductive material. (Hereinafter referred to as “insulating coating 12”). The insulating coating 12 is provided with a net-like hatch for easy understanding. Although it does not make sense to discuss the “front and back” of the snare loop 10, it is expressed as “front and back” for convenience.
[0014]
The insulating coating 12 may be applied over the entire length of the elastic wire 11 forming the snare loop 10, but the insulating coating 12 is applied to at least a portion on the distal end side that touches human tissue in a state where the polyp is tightly bound by the snare loop 10. It only has to be.
[0015]
As the insulating coating 12, for example, a synthetic resin material such as a fluororesin, an epoxy resin, or a polyimide resin can be used, and a dissolved resin may be applied instead of the coating.
[0016]
However, since the portion where the elastic wire 11 comes into contact with human tissue when energized with a high-frequency current is heated by Joule heat, it is necessary to use a material having a heat resistance of a certain level or more as the insulating coating 12, and a harmful gas or the like by heating. Must not occur.
[0017]
FIG. 3 shows that the polyp 100 is cut by operating the operation unit (not shown) to pull the operation wire 2 toward the hand side, binding the polyp with the snare loop 10 and energizing the elastic wire 11 with a high-frequency current. It shows the state of being applied.
[0018]
As shown in FIG. 3, the surface of the elastic wire 11 on which the insulating coating 12 is not applied is directed to the mucosal surface (the floor side surface from which the polyp 100 protrudes), and the insulating coating 12 is used. This surface is directed toward the tip side of the polyp 100.
[0019]
As shown in FIG. 4 which shows the longitudinal section of the polyp 100 by passing a high-frequency current through the elastic wire 11 of the snare loop 10 as described above, the human tissue in the portion in contact with the elastic wire 11 is caused by Joule heat. The polyp 100 is cut without bleeding while being heated and solidified.
[0020]
At that time, almost no Joule heat is generated in the polyp tissue portion in contact with the insulating coating 12, so that the section tissue of the polyp 100 cut by the snare loop 10 is not thermally destroyed (thermal destruction part A) and recovered. The section of the polyp 100 thus obtained can be used for histological examination.
[0021]
In this embodiment, as shown in FIG. 4, the insulating coating 12 covers about half (180 °) in the circumferential direction of the outer circumference of the elastic wire 11, but as shown in FIG. If the range covered by the insulating coating 12 is further increased in the circumferential direction, the thermal destruction portion A will not reach the section side of the polyp 100 more.
[0022]
Note that the present invention is not limited to the above-described embodiment. In short, only one of the front and back surfaces of the vicinity of the tip of the snare loop may be formed of an electrical insulating material or a defective conductive material, and its means is Any means other than coating and painting may be used.
[0023]
【The invention's effect】
According to the present invention, only one of the front and back surfaces of the vicinity of the tip of the snare loop is formed of an electrically insulating material or a defective conductive material, so that a polyp tissue portion in contact with that surface is subjected to high-frequency current energization. Since no heat is generated, the polyp can be cut without bleeding by Joule heat generated at the contact surface between the opposite surface of the snare loop and the mucosal tissue without thermally destroying the polyp section tissue. .
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state in which a snare loop of a high-frequency endoscope snare according to a first embodiment of the present invention is pulled into a flexible sheath halfway.
FIG. 2 is a plan sectional view of the distal end portion of the high-frequency endoscope snare according to the first embodiment of the present invention.
FIG. 3 is a perspective view of a state in which a polyp is being cut by the endoscope high-frequency snare according to the first embodiment of the present invention.
FIG. 4 is a longitudinal sectional view showing a state in which a polyp is being cut by the endoscope high-frequency snare according to the first embodiment of the present invention.
FIG. 5 is a longitudinal sectional view showing a state in which a polyp is being cut by a high-frequency endoscope snare according to a second embodiment of the present invention.
FIG. 6 is a perspective view of a state in which a polyp is being cut by a conventional endoscope high-frequency snare.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Flexible sheath 2 Operation wire 10 Snare loop 11 Elastic wire 12 Insulating coating 100 Polyp A Thermal destruction part

Claims (1)

An operation wire is inserted and arranged in the flexible sheath so as to be movable back and forth in the axial direction, and a snare loop formed of a conductive elastic wire is connected to the tip of the operation wire and a high-frequency current is passed through the snare loop The snare loop moves in and out of the distal end of the flexible sheath by moving the operating wire forward and backward in the axial direction, and the snare loop is elastically elastic outside the flexible sheath. In a high frequency snare for an endoscope which is swelled and narrowed by being drawn into the flexible sheath,
A high frequency snare for an endoscope, wherein only one of the front and back surfaces of the vicinity of the tip of the snare loop is formed of an electrical insulating material or a defective conductive material.

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