JP4321853B2 - Endoscopic high-frequency snare - Google Patents

Description

  The present invention relates to an endoscopic high-frequency snare that is passed through a treatment instrument insertion channel of an endoscope and used for performing polypectomy or the like.

  In general, a high-frequency snare for an endoscope has an operation wire inserted through an electrically insulating sheath so as to be movable back and forth in the axial direction, and a snare loop made of an elastic wire is connected to the tip of the operation wire. The snare loop moves in and out of the distal end of the sheath by advancing and retracting in the direction, and the snare loop is swollen by its own elasticity outside the sheath and is elastically deformed and constricted by being pulled into the sheath. .

  In a conventional endoscope high-frequency snare, each of the operation wire and the snare loop is formed of a conductive metal wire, and a high-frequency current is sent to the snare loop via the operation wire. The biological mucous membrane that touches the body is cauterized by Joule heat (for example, Patent Document 1).

Also, in order to assist cauterization near the end of the snare loop near the sheath, an electrode is also arranged at the tip of the sheath so that high-frequency current can be passed through both the snare loop and the electrode, etc. (For example, Patent Document 2).
JP 2000-83963 A JP-A-11-347045

  FIG. 9 shows a state of polyp excision by a conventional endoscopic high-frequency snare, and the polyp 100 is fastened by the snare loop 3 of the high-frequency snare projecting from the treatment instrument insertion channel 51 of the endoscope 50. A high frequency current is passed through the snare loop 3.

  Then, although the mucous membrane touched by the snare loop 3 is cauterized by Joule heat, the snare loop 3 is constricted by being drawn into the flexible tube 1, so what is the binding state of the polyp 100 by the snare loop 3? Even in such a case, the portion near the tip of the snare loop 3 bites into the mucous membrane and is cauterized best. This is the same in any case of the high-frequency snare described in Patent Documents 1 and 2 described above.

  However, the portion near the tip of the snare loop 3 that exhibits the greatest cauterization effect becomes a shadow of the polyp 100 when observed through the observation window 52 of the endoscope 50 and cannot be observed.

  Therefore, if the mucous membrane or the submucosal muscle layer that was not intended to be resected is accidentally cauterized and damaged, or if the position shallower than the part to be resected is cauterized, the malignant mucosal part may be left behind. Etc.

  Therefore, the present invention cauterizes and excises only the target portion accurately while cauterizing only the portion of the polyp that is tightly bound by the snare loop that can be endoscopically observed with a high-frequency current, and reliably viewing the endoscopic observation. An object of the present invention is to provide an endoscopic high-frequency snare that can be used.

  In order to achieve the above object, an endoscope high-frequency snare according to the present invention has an operation wire inserted and disposed in an electrically insulating sheath so as to be movable back and forth in the axial direction, and is made of an elastic wire at the tip of the operation wire. The snare loop is connected, and the snare loop moves in and out of the distal end of the sheath by moving the operation wire forward and backward in the axial direction. The snare loop expands by its own elasticity outside the sheath and is elastically deformed by being pulled into the sheath. In the endoscopic high-frequency snare configured so as to be narrowed, a tip electrode to which a high-frequency current is applied is disposed in a state of being exposed forward in an opening portion where the snare loop at the tip of the sheath enters and exits. The snare loop is electrically insulated from the tip electrode, and no high-frequency current flows through the snare loop even when a high-frequency current is applied to the tip electrode. Those were Unishi.

  In addition, a conductive wire for sending a high-frequency current to the tip electrode may be inserted and arranged in the sheath along with the operation wire, and the snare loop itself may be formed of an electrical insulating material, or The surface of the conductive wire may be formed by covering with an electric insulating material.

  Further, the tip electrode may be provided with a through-hole through which the elastic wire constituting the snare loop passes, and in this case, the tip surface protruding from the tip of the sheath of the tip electrode is compared to the rear part. It may be formed narrow.

  Further, the tip electrode may be a plate-like member arranged side by side with the elastic wire constituting the snare loop, or may be a cylindrical member inserted and fixed in the tip opening portion of the sheath.

  According to the present invention, the tip electrode to which a high-frequency current is passed is exposed in the opening portion where the snare loop at the tip of the sheath enters and exits, and the snare loop is electrically insulated from the tip electrode. Since the high-frequency current does not flow through the snare loop even when the tip electrode is energized, only the part of the polyp that is bound by the snare loop can be observed with the high-frequency current. Thus, only the target portion can be accurately cauterized and excised while being surely recognized by endoscopic observation.

  In the opening part where the snare loop at the tip of the sheath enters and exits, the tip electrode to which a high-frequency current is passed is disposed so as to be exposed forward, and the snare loop is electrically insulated from the tip electrode to form the tip electrode. Even when a high frequency current is applied, the high frequency current does not flow in the snare loop, and a conductive wire for sending the high frequency current to the tip electrode is inserted and arranged alongside the operation wire in the sheath.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows the overall configuration of an endoscope high-frequency snare, and an operation wire 2 is inserted and disposed in an electrically insulating flexible tube 1 made of, for example, a tetrafluoroethylene resin tube or the like so as to be movable back and forth in the axial direction. A snare loop 3 made of an elastic wire is connected to the tip of the operation wire 2 at the tip of the flexible tube 1.

  In the operation unit 20 disposed on the proximal end side of the flexible tube 1, a slide operation member 22 is attached so as to be slidable with respect to the operation unit main body 21 connected to the proximal end of the flexible tube 1. The proximal end of the operation wire 2 is connected to the slide operation member 22.

  As a result, the snare loop 3 moves in and out of the distal end of the flexible tube 1 by moving the operation wire 2 forward and backward in the axial direction with the slide operation member 22, and the snare loop 3 is self-exposed outside the flexible tube 1. It swells due to elasticity and is drawn into the flexible tube 1 to be elastically deformed and constricted.

  In the opening portion where the snare loop 3 at the tip of the flexible tube 1 enters and exits, the tip electrode 4 to which a high-frequency current is passed is disposed so as to be exposed forward, and a high-frequency power cord (not shown) is attached. Between the high-frequency power connection pin 24 projecting from the operation unit main body 21 and the tip electrode 4 so as to be connected, the conductive wire 6 inserted in the flexible tube 1 along with the operation wire 2 is electrically connected. Is conducting.

  2 is a plan sectional view of the distal end portion of the endoscope high-frequency snare in a state where the snare loop 3 is pushed out of the distal end of the flexible tube 1 and swells, and FIG. 3 is a side sectional view thereof. FIG. 3 is a perspective view of the distal end portion of the endoscope high-frequency snare in a state in which the distal end electrode 4 attached to the distal end of the flexible tube 1 is pulled out from the distal end portion of the flexible tube 1.

  The tip electrode 4 is formed in a substantially cylindrical shape, and is fitted into the tip opening of the flexible tube 1 so as to be slightly exposed (for example, about 0.5 to 2 mm) from the tip of the flexible tube 1 to the front. Thus, a pair of retaining protrusions 4x that bite into the inner peripheral surface of the flexible tube 1 so as to restrict axial movement from that state are formed to protrude from the outer peripheral portion of the tip electrode 4.

  In addition, a pair of wire passage holes 4a for allowing the elastic wire 3a constituting the snare loop 3 to pass loosely are formed in parallel with the tip electrode 4 penetrating the entire length in the axial direction.

  The tip surface 4b of the tip electrode 4 at a position protruding forward from the tip of the flexible tube 1 and having the wire passage hole 4a opened is formed narrower than the rear portion of the tip electrode 4 and has a surface area. Has been made smaller. In addition, you may form the front end surface 4b of the front-end | tip electrode 4 in a roof-shaped taper shape.

  A portion in the vicinity of the rear end of the tip electrode 4 is formed to be narrow like the tip portion, and the tip portion of the conductive wire 6 is joined to that portion. Therefore, a high-frequency current can be supplied to the tip electrode 4 from the high-frequency power cord attached to the high-frequency power connection pin 24 of the operation unit 20 via the conductive wire 6.

  4 c is a water feed hole formed through the tip electrode 4 in the axial direction so as to allow the vicinity of both front and rear end portions of the tip electrode 4 to communicate with each other. By pouring water into the inside, water can be discharged from the front end opening of the water supply passage 4c to the front.

  The elastic wire 3a constituting the snare loop 3 is formed of a non-conductive material such as a tetrafluoroethylene resin or a polyamide resin, and two wires are bundled together at the base end portion, and the connection pipe 7 is joined to the operation wire 2 through 7.

  The operation wire 2 is formed of, for example, a stranded wire obtained by twisting a stainless steel wire or a single wire, but it is more preferable that an outer surface is coated with an electrical insulating material. Similarly, the elastic wire 3a forming the snare loop 3 may be formed by applying an electrical insulating material coating or tube coating to a metal wire.

  With such a configuration, when the operation wire 2 is advanced and retracted in the operation unit 20, the movement is transmitted to the snare loop 3 through the operation wire 2, and the snare loop enters and exits the distal end of the flexible tube 1. The snare loop 3 swells by its own elasticity outside the flexible tube 1, and is elastically deformed and narrowed by being drawn into the flexible tube 1. Since the snare loop 3 is electrically insulated from the tip electrode 4, no high frequency current flows through the snare loop 3 even when a high frequency current is passed through the tip electrode 4.

  FIG. 5 shows a state in which the polyp 100 is excised transendoscopically using the endoscope high-frequency snare of the above-described embodiment, and the distal end extends from the treatment instrument insertion channel 51 of the endoscope 50. A high-frequency current is passed through the tip electrode 4 while the polyp 100 is bound by the protruding snare loop 3 of the high-frequency snare.

  Then, the mucous membrane in contact with the tip electrode 4 is cauterized by Joule heat and the polyp 100 is excised, but the high frequency current does not flow through the snare loop 3, and the cauterized part by the high frequency current is the endoscope 50 of the polyp 100. Since only the near part is present, the state of cauterization can be observed through the observation window 52 of the endoscope 50, and the target part can be cauterized and excised accurately.

  In addition, this invention is not limited to the said Example, For example, as FIG. 6 shows, the front-end | tip electrode 4 is formed with an electroconductive plate-shaped member, and is forward from the front-end | tip of the flexible tube 1. As shown in FIG. You may arrange | position in the front-end | tip of the flexible tube 1 along with the elastic wire 3a which comprises the snare loop 3 so that it may protrude.

  Further, as shown in FIGS. 7 and 8, a conductive cylindrical member as the tip electrode 4 is disposed in the tip of the flexible tube 1 so as to protrude forward from the tip of the flexible tube 1. Also good. The tip electrode 4 of the embodiment of FIG. 7 is screwed and fixed to the tip opening of the flexible tube 1, and the tip electrode 4 of the embodiment of FIG. 8 is pressed and fixed at the tip portion of the flexible tube 1.

It is a top view which shows the whole structure of the high frequency snare for endoscopes of the 1st Example of this invention. It is a plane sectional view in the state where the snare loop of the high frequency snare tip part for endoscopes of the 1st example of the present invention expanded. It is side surface sectional drawing of the state which the snare loop of the high frequency snare tip part for endoscopes of the 1st Example of this invention swelled. It is a perspective view of the member accommodated in the front-end | tip part of the sheath of the high frequency snare for endoscopes of the 1st Example of this invention. It is a perspective view which shows the state which is performing polypectomy with the high frequency snare for endoscopes of the 1st Example of this invention. It is a perspective view of the front-end | tip part of the high frequency snare for endoscopes of the 2nd Example of this invention. It is a plane sectional view of the tip part of the high frequency snare for endoscopes of the 3rd example of the present invention. It is a plane sectional view of the tip part of the high frequency snare for endoscopes of the 4th example of the present invention. It is a perspective view which shows the state which is performing polypectomy with the conventional high frequency snare for endoscopes.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flexible sheath 2 Operation wire 3 Snare loop 4 Tip electrode 4b Tip surface 6 Conductive wire

Claims (8)

An operation wire is inserted and disposed in an electrically insulating 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 advanced and retracted in the axial direction. The endoscope is configured such that the snare loop enters and exits the distal end of the sheath, the snare loop expands by its own elasticity outside the sheath, and is elastically deformed and narrowed by being pulled into the sheath. In high frequency snare,
At the opening of the snare loop at the distal end of the sheath, a tip electrode to which a high-frequency current is passed is disposed so as to be exposed forward, and the snare loop is electrically insulated from the tip electrode. A high-frequency snare for an endoscope, wherein a high-frequency current does not flow through the snare loop even when a high-frequency current is applied to the tip electrode. The high frequency snare for an endoscope according to claim 1, wherein a conductive wire for sending a high frequency current to the tip electrode is inserted and arranged in the sheath along with the operation wire. The high-frequency snare for endoscope according to claim 1 or 2, wherein the snare loop is formed of an electrical insulating material. The high-frequency snare for an endoscope according to claim 1 or 2, wherein the snare loop is formed by covering a surface of a conductive wire with an electrical insulating material. The high frequency snare for an endoscope according to claim 1, 2, 3, or 4, wherein a through hole through which an elastic wire constituting the snare loop passes is formed in the tip electrode. The high-frequency endoscope snare according to claim 5, wherein a distal end surface of the distal electrode protruding from the distal end of the sheath is formed narrower than a rear portion thereof. The high-frequency snare for an endoscope according to claim 1, 2, 3, or 4, wherein the tip electrode is a plate-like member arranged side by side with an elastic wire constituting the snare loop. The high-frequency snare for endoscope according to claim 1, 2, 3, or 4, wherein the tip electrode is a cylindrical member inserted and fixed to a tip opening portion of the sheath.

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