JP2014054372A - Liquid feeding knife - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid feeding knife with a tubular electrode prevented from being broken even when subjected to bending stress at a high temperature.SOLUTION: A liquid feeding knife 1 includes: a sheath 11; a support member 21 provided at the tip of the sheath 11 and formed into a cylindrical shape; an axial member 12 formed of a conductive material and retractably inserted into the sheath; a tubular electrode 22 connected to the axial member to project and recess through a cylinder hole 21b of the support member, provided with a duct line 22d capable of jetting forward a fluid L, and formed of a conductive material to treat a biological tissue; and a locking part 25 provided on the tubular electrode and locked on the support member when the axial member is moved toward the tip side with respect to the sheath to project the tubular electrode from the cylinder hole of the support member toward the tip. Assuming a position where the tubular electrode is disposed at the tip of the support member in locking the locking part on the support member, as a projection reference position T, a heat-resistant metal member 24 is provided on the outer peripheral surface of the tubular electrode in a range including the projection reference position in the axial direction.

Description

  The present invention relates to a liquid feeding knife capable of incising a living tissue and ejecting fluid forward.

  2. Description of the Related Art Conventionally, treatment using a feeding knife capable of incising a biological tissue such as a mucous membrane endoscopically and injecting a medical solution or a physiological saline from a distal end portion has been performed. As such a liquid feeding knife, for example, those described in Patent Documents 1 and 2 are known.

In this liquid-feeding knife, a tubular electrode member (tubular electrode) is connected and fixed to the tip of an inner tube (shaft-shaped member) that is inserted and disposed in an outer tube (sheath) so as to be movable back and forth in the axial direction. Therefore, the tubular electrode protrudes and retracts from the distal end of the outer tube by moving the inner tube back and forth in the axial direction within the outer tube.
On the inner surface near the tip of the outer tube, a stopper made of a metal ring for restricting the tubular electrode from protruding too much is arranged. Moreover, the collar part which protruded from the outer peripheral surface is formed in the latter half part of the tubular electrode. When the collar comes into contact with the stopper, the tubular electrode protrudes a predetermined length from the distal end of the outer tube so that it cannot protrude any further. A conductive wire is inserted into the inner tube, and the tip of the conductive wire is connected to the vicinity of the rear end of the tubular electrode.

  In the liquid feeding knife configured as described above, the drug solution (fluid) can be sent to the tubular electrode through the inner tube by the injection cylinder. A high frequency voltage can be applied to the tubular electrode through a conductive wire by a high frequency power source.

JP 11-1114060 A JP 2001-178740 A

In the liquid feeding knives described in Patent Documents 1 and 2, a high-frequency voltage is continuously applied to the tubular electrode when a living tissue is incised. A cut-out extending along the surface of the living tissue is formed by inserting the tubular electrode into the living tissue and moving the tubular electrode in a direction orthogonal to the axial direction. At this time, the tubular electrode receives a bending stress in a direction orthogonal to the axial direction.
The tubular electrode is generally made of stainless steel. The tubular electrode to which the high frequency voltage has been continuously applied has a temperature of about 300 ° C., for example. Under such a high temperature, the mechanical properties (strength) such as the longitudinal elastic modulus of the tubular electrode deteriorates or becomes brittle. When the tubular electrode in this state is subjected to bending stress, there is a problem that the bending stress concentrates on the portion of the tubular electrode protruding from the stopper and is disposed at the tip of the stopper, and the tubular electrode breaks from this portion.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a liquid-feeding knife that suppresses breakage of a tubular electrode even when subjected to bending stress at high temperatures. And

In order to solve the above problems, the present invention proposes the following means.
The liquid-feeding knife of the present invention is connected to the distal end of the operation unit and is formed in a cylindrical shape with a sheath formed of an insulating material, and provided at the distal end portion of the sheath and having an electrically insulating property. Connected to the support member, a shaft-shaped member formed of a conductive material and inserted in the sheath so as to be able to advance and retract, and connected to the tip of the shaft-shaped member so as to protrude and retract through the cylindrical hole of the support member And a tube formed of a conductive material for performing treatment of a living tissue by power feeding through the shaft-like member, and a conduit capable of ejecting the fluid supplied into the sheath forward is formed. An electrode and the shaft-shaped member or the tubular electrode, and when the shaft-shaped member is moved to the distal end side with respect to the sheath to project the tubular electrode from the tubular hole of the support member to the distal end side To the support member And a position of the tubular electrode disposed at the distal end of the support member in the axial direction of the sheath when the support member is locked with the lock portion. Sometimes, the outer peripheral surface of the tubular electrode is provided with a heat-resistant metal member in a range including the protruding reference position in the axial direction.

In the liquid feeding knife, the heat-resistant metal member is provided in a range from the protruding reference position on the outer peripheral surface of the tubular electrode to the protruding reference position in the axial direction from the protruding reference position by 0.5 mm. More preferably.
In the liquid feeding knife, it is more preferable that the heat-resistant metal member is composed of at least one of tungsten, tantalum, molybdenum, nickel alloy, and titanium.
In the liquid feeding knife, the shaft-shaped member is an operation wire, and the tubular electrode is formed with a communication hole that communicates the internal space of the sheath and the conduit of the tubular electrode. Is more preferable.

  According to the liquid-feeding knife of the present invention, it is possible to provide a liquid-feeding knife in which the tubular electrode is prevented from breaking even when subjected to bending stress at high temperatures.

It is a general view of the liquid feeding knife of one Embodiment of this invention. It is sectional drawing of the side surface of the front end side when making the liquid feeding knife into the pushing state. It is a cross-sectional view of the tubular electrode of the liquid feeding knife. It is sectional drawing of the side surface of the front end side when the same liquid feeding knife is made into the drawing-back state. It is a figure which shows the state when the lesioned mucous membrane part is raised explaining the procedure using the liquid feeding knife. It is a figure which shows the state when incising the lesioned mucosa part explaining the procedure using the liquid feeding knife. It is a figure which shows the state which exfoliates the lesioned mucous membrane part explaining the procedure using the liquid feeding knife. It is a cross-sectional view of the tubular electrode of the liquid feeding knife in the embodiment of the modification of the present invention. It is a cross-sectional view of the tubular electrode of the liquid feeding knife in the embodiment of the modification of the present invention.

Hereinafter, an embodiment of a liquid-feeding knife according to the present invention will be described with reference to FIGS. 1 to 9.
As shown in FIG. 1, the liquid-feeding knife 1 of this embodiment includes a flexible insertion portion 10 and a treatment portion 20 provided at the distal end portion of the insertion portion 10.

As shown in FIG. 2, the insertion portion 10 includes a sheath 11 and an operation wire (axial member) 12 that is inserted into the sheath 11 so as to be able to advance and retract in the direction of the axis C <b> 1 of the sheath 11.
The sheath 11 is formed of an electrically insulating material such as a tetrafluoroethylene material. The outer diameter of the sheath 11 is set to a size that can be inserted through a channel of an endoscope (not shown).
The operation wire 12 is formed of a conductive material such as metal.
In the present embodiment, a liquid feeding base 14 in which an injection port 14 a communicating with the internal space 11 a of the sheath 11 is formed is attached to the proximal end portion of the sheath 11 via a cylindrical connection member 15. On the outer peripheral surface of the connecting portion between the sheath 11 and the liquid feeding base 14, a fold prevention tube 16 is attached to prevent the base end portion from being bent when the base end portion of the sheath 11 is bent. Yes.
In the liquid feeding base 14, the inlet 14 a and the operation wire 12 are sealed in a water-tight manner, and the operation wire 12 is supported with respect to the liquid feeding base 14 so as to be movable back and forth in the direction of the axis C <b> 1. A sealing material is provided. Although not shown, a liquid feeding means such as a syringe can be attached to and detached from the inlet 14a.

The treatment section 20 includes an insulating tip (support member) 21 formed in a cylindrical shape and provided at the distal end portion of the sheath 11, and a tubular electrode member (tubular electrode) 22 connected to the distal end portion of the operation wire 12. Have.
On the outer peripheral surface on the proximal end side of the insulating chip 21, a reduced diameter portion 21 a having a diameter reduced from the distal end side is formed. The insulating chip 21 is made of an insulating material such as zirconia or ceramics.
The tubular electrode 22 is formed of a conductive material such as stainless steel. The distal end of the tubular electrode 22 is provided with a large-diameter portion 22 a whose outer diameter is set larger than other portions of the tubular electrode 22. In the present embodiment, the outer diameter of the tubular electrode 22 other than the large diameter portion 22a is set to about 0.3 mm to 0.5 mm, for example. A communication hole 22b penetrating from the outer peripheral surface to the inner peripheral surface of the tubular electrode 22 is formed in an intermediate portion of the tubular electrode 22 in the direction of the axis C1.

As shown in FIGS. 2 and 3, a heat-resistant metal member 24 is provided on the outer circumferential surface of the tubular electrode 22 over the entire circumference. Here, as will be described later, when the stopper member 25 is locked to the insulating chip 21, the position of the tubular electrode 22 arranged at the tip of the insulating chip 21 in the direction of the axis C1 is defined as the protruding reference position T (FIG. 2).
In the present embodiment, the heat-resistant metal member 24 is provided in a range from the protrusion reference position T on the outer peripheral surface of the tubular electrode 22 to the proximal end side from the protrusion reference position T in the axis C1 direction by 0.5 mm from the protrusion reference position T. It has been. That is, in this example, the heat-resistant metal member 24 is formed in a cylindrical shape.

The heat resistant metal member 24 is made of, for example, molybdenum. The heat-resistant metal member 24 adheres, for example, molybdenum powder to a step portion 22c formed on the outer peripheral surface of the tubular electrode 22 so as to reduce the diameter with the communication hole 22b sandwiched in the direction of the axis C1. It can be formed by bonding.
The heat-resistant metal member 24 formed in this way does not deteriorate in mechanical properties such as longitudinal elastic modulus or become brittle even at a high temperature of about 300 ° C.
The outer diameter of the tubular electrode 22 on the proximal end side with respect to the large diameter portion 22 a is set slightly smaller than the inner diameter of the cylindrical hole 21 b of the insulating chip 21. On the other hand, the outer diameter of the large diameter portion 22a of the tubular electrode 22 is set larger than the inner diameter of the cylindrical hole 21b.

A cylindrical stopper member (locking portion) 25 is attached to the outer peripheral surface of the connection portion between the tubular electrode 22 and the operation wire 12, and the stopper member 25 connects the tubular electrode 22 and the operation wire 12. . The stopper member 25 is formed with a through hole 25a penetrating the stopper member 25 from the outer peripheral surface to the inner peripheral surface. The through hole 25 a of the stopper member 25 communicates with the communication hole 22 b of the tubular electrode 22.
The outer diameter of the stopper member 25 is set larger than the inner diameter of the cylindrical hole 21b of the insulating chip 21.

In the present embodiment, the liquid feeding knife 1 includes an operation unit 30 provided at the proximal end portion of the insertion unit 10 as shown in FIG.
The operation unit 30 includes an operation unit main body 31 fixed to the proximal end portion of the liquid feeding base 14 and an operation slider 32 that can slide with respect to the operation unit main body 31. A guide shaft portion 31a is formed in the operation portion main body 31 along the axis C1. The operation slider 32 is slidable along the axis C <b> 1 with respect to the operation unit main body 31. The operation unit body 31 includes a finger ring 31b at the base end.
The operation slider 32 includes finger-hooking rings 32a and 32b arranged in a direction perpendicular to the axis C1. The operation slider 32 includes a connection connector portion 33 to which a cord leading to a high frequency generator (not shown) is electrically connected.
The connection connector portion 33 is electrically connected to the proximal end portion of the operation wire 12.

In the liquid feeding knife 1 configured in this way, for example, the operator's thumb is inserted into the ring 31b of the operation unit main body 31, and the index finger and middle finger are inserted into the rings 32a and 32b of the operation slider 32. By operating with the index finger and the middle finger, the operation slider 32 can be slid in the direction of the axis C1 with respect to the operation portion main body 31.
Then, when the operation wire 12 is moved (pushed) toward the distal end side with respect to the sheath 11 by moving the operation slider 32 toward the distal end side with respect to the operation portion main body 31, the insulating chip 21 is moved to the insulating chip 21 as shown in FIG. By locking the stopper member 25, the pushed-in state in which the operation wire 12 is pushed toward the distal end side is positioned.
In this pushed-in state, the tubular electrode 22 can be projected to the tip side through the cylindrical hole 21b of the insulating chip 21. Then, the physiological saline (fluid) L supplied to the internal space 11 a of the sheath 11 is jetted forward through the through hole 25 a of the stopper member 25, the communication hole 22 b of the tubular electrode 22, and the conduit 22 d of the tubular electrode 22. be able to.
Note that the length D of the tubular electrode 22 protruding from the insulating tip 21 when the liquid feeding knife 1 is pushed in is set to 2 mm, for example.

  On the other hand, when the operation wire 12 is moved to the proximal end side with respect to the sheath 11 by moving the operation slider 32 to the proximal end side with respect to the operation portion main body 31 (retracted), as shown in FIG. The proximal end side of the tubular electrode 22 is accommodated in the internal space 11 a of the sheath 11, and the large diameter portion 22 a comes into contact with the distal end surface of the insulating chip 21. Thereby, the retracted state in which the operation wire 12 is pulled back to the proximal end side is positioned.

Next, the operation of the feeding knife 1 configured as described above will be described. Below, the operation | movement at the time of performing the mucosal resection in a body cavity, for example, endoscopically using the liquid feeding knife 1 is demonstrated.
First, a counter electrode plate (not shown) is attached to the patient. Through a channel of an endoscope (not shown), the liquid feeding knife 1 brought into a retracted state is introduced into a body cavity endoscopically. At this time, the image acquired by the observation unit of the endoscope is introduced while being observed on a display unit such as a monitor.
The distal end portion of the insertion portion 10 of the liquid feeding knife 1 is projected from the channel of the endoscope, and the treatment portion 20 is opposed to the lesioned mucosa portion that is the target site to be excised in the body cavity.

A syringe (not shown) is attached to the injection port 14a. The surgeon or assistant puts his fingers into the rings 31b, 32a and 32b, pushes the operation slider 32 toward the distal end side with respect to the operation section main body 31, and pushes the liquid feeding knife 1 to protrude the tubular electrode 22. Let As shown in FIG. 5, the tubular electrode 22 is inserted in the vicinity of the lesion mucosa portion P <b> 1, and the physiological saline L accommodated in the syringe is supplied to the internal space 11 a of the sheath 11 and ejected forward from the tubular electrode 22. The ejected physiological saline L is injected into the submucosal layer of the lesioned mucosa portion P1, and raises the lesioned mucosa portion P1.
In addition, in the liquid feeding knife 1 of this embodiment, the operation | movement which ejects the physiological saline L from the tubular electrode 22 can be performed even when the liquid feeding knife 1 is made into the pull-back state.

Next, a high frequency generator (not shown) is connected to the connection connector 33 of the operation unit 30. A high frequency voltage is applied to the tubular electrode 22 via the connection connector portion 33 and the operation wire 12 by the high frequency generator. At this time, the tubular electrode 22 and the heat-resistant metal member 24 are at a high temperature as described above.
As shown in FIG. 6, when the tubular electrode 22 of the liquid feeding knife 1 is moved in the lateral direction perpendicular to the axis C <b> 1, the tubular electrode 22 receives bending stress from the mucosa that contacts the tubular electrode 22 and contacts the tubular electrode 22. The mucosa is incised.

  The tubular electrode 22 is bent with the tip of the inner peripheral surface of the cylindrical hole 21b of the insulating chip 21 as a fulcrum. For this reason, the bending stress acts larger in the tubular electrode 22 as it approaches the insulating chip 21 in the radial direction as it approaches the protrusion reference position T in the direction of the axis C1. That is, the bending stress acts more as it approaches the tip of the inner peripheral surface of the cylindrical hole 21 b of the insulating chip 21. However, the heat-resistant metal member 24 is provided on the outer peripheral surface of the tubular electrode 22 in a range including the protruding reference position T in the direction of the axis C1. Since the mechanical properties of the refractory metal member 24 do not deteriorate even at high temperatures, the possibility that the refractory metal member 24 breaks is lower than when stainless steel is used for the refractory metal member.

  Since the heat-resistant metal member 24 is provided only to the tip side of 0.5 mm from the protrusion reference position T, the heat-resistant metal is within a range of about 1.5 mm on the tip side of the tubular electrode 22 protruding from the insulating chip 21. The member 24 is not provided. Therefore, in the liquid feeding knife 1 of this embodiment, the mucous membrane is basically incised by the tubular electrode 22 formed of stainless steel, and even if the tubular electrode 22 is provided with the heat-resistant metal member 24, the tissue The incision property is maintained at the same level as that of a conventional liquid feeding knife.

When the lesioned mucosa portion P1 is completely incised in the circumferential direction in this way, as shown in FIG. 7, the tubular electrode 22 is brought into contact with the incision P2 that has been incised around the lesioned mucosa portion P1, thereby causing the lesioned mucosa portion P1. Are sequentially incised to excise and remove all the mucosa portion P1 of the lesion.
The liquid feeding knife 1 is pulled back and pulled out from the endoscope channel to the hand side. A grasping forceps or the like (not shown) is inserted through the empty channel of the endoscope. By operating the grasping forceps, the lesioned mucous membrane portion P1 is taken out endoscopically, and a series of treatments is completed.

As described above, according to the liquid feeding knife 1 of the present embodiment, the physiological saline L is supplied to the internal space 11a of the sheath 11 with the liquid feeding knife 1 pushed in, so that the forward direction from the tubular electrode 22 is achieved. The physiological saline L can be ejected. By applying a high frequency voltage to the tubular electrode 22 from the high frequency generator via the operation wire 12, the mucous membrane in contact with the tubular electrode 22 can be incised.
When a high frequency voltage is applied to the tubular electrode 22, the tubular electrode 22 becomes as high as about 300 ° C., but the outer surface of the tubular electrode 22 includes a heat-resistant metal member 24 within a range including the protruding reference position T in the direction of the axis C <b> 1. Is provided. Since the mechanical properties of the refractory metal member 24 do not deteriorate even at high temperatures, the possibility of breaking even when bending stress is applied is low, and the tubular electrode 22 can be prevented from breaking at high temperatures.

  The heat-resistant metal member 24 is provided in a range from the front end side of 0.5 mm to the protrusion reference position T with respect to the protrusion reference position T on the outer peripheral surface of the tubular electrode 22 in the direction of the axis C1. For this reason, the mucous membrane can be incised with stainless steel heated to a high temperature on the tip side from the range where the heat-resistant metal member 24 is provided, similarly to the conventional liquid feeding knife. Thereby, even if the heat-resistant metal member 24 is provided on the tubular electrode 22, the dissection property of the tissue can be maintained at the same level as that of the conventional liquid feeding knife.

As mentioned above, although one Embodiment of this invention was explained in full detail with reference to drawings, the concrete structure is not restricted to this Embodiment, The change of the structure of the range which does not deviate from the summary of this invention is included. .
For example, in the above embodiment, the heat-resistant metal member 24 is made of molybdenum. However, the material forming the refractory metal member 24 is not limited to this, and may be made of at least one of tungsten, tantalum, molybdenum, nickel alloy, and titanium.

Although the heat-resistant metal member 24 is formed in a cylindrical shape, it may be configured as follows.
As shown in FIG. 8, a plurality of heat-resistant metal members 41 may be provided on the outer circumferential surface of the tubular electrode 22 at intervals in the circumferential direction of the sheath 11. In this modified example, each heat-resistant metal member 41 has a cross-sectional shape formed by a plane orthogonal to the direction of the axis C1 in an arc shape and extends in the direction of the axis C1. Each heat-resistant metal member 41 has a surface on the side away from the axis C1 exposed to the outside when the liquid feeding knife 1 is pushed in, and a surface on the axis C1 side is embedded in the tubular electrode 22.
In the modification shown in FIG. 9, a plurality of heat-resistant metal members 43 are attached to the outer peripheral surface of the tubular electrode 22 without being embedded. Each refractory metal member 43 has a circular cross section formed by a plane orthogonal to the direction of the axis C1.
Even if the heat-resistant metal members 41 and 43 are configured in this manner, the same effects as those of the heat-resistant metal member 24 of the above-described embodiment can be obtained.

In the above embodiment, the heat-resistant metal member 24 is provided over a range from the front end side of 0.5 mm from the protrusion reference position T to the base end side from the protrusion reference position T. It suffices if it is provided in a range including the protruding reference position T in the direction of the axis C1, and preferably in a range from the leading end side of 0.5 mm from the protruding reference position T to the proximal side of 0.5 mm from the protruding reference position T. What is necessary is just to be provided. This is because the mechanical characteristics of the tubular electrode 22 at a high temperature can be enhanced even with this configuration.
In the above embodiment, the stopper member 25 is attached to the connection portion between the tubular electrode 22 and the operation wire 12, but the stopper member may be attached to the tubular electrode 22 or the operation wire 12.

In the above embodiment, the shaft member is the operation wire 12, and the physiological saline L is supplied to the conduit 22d of the tubular electrode 22 through the communication hole 22b. However, the shaft-shaped member is not limited to this. For example, the shaft-shaped member is an inner sheath formed of a conductive material, and the conduit 22d of the tubular electrode 22 and the inner space of the inner sheath communicate with each other. At the same time, the physiological saline L may be supplied to the conduit 22d of the tubular electrode 22 through the internal space of the inner sheath.
In the above embodiment, the fluid is physiological saline, but the fluid may be a chemical solution or the like.

1 Liquid feeding knife 11 Sheath 12 Operation wire (shaft-shaped member)
21 Insulating chip (supporting member)
21b Tubular hole 22 Tubular electrode 22b Communication hole 22d Pipe line 24, 41, 43 Heat-resistant metal member 25 Stopper member (locking part)
C1 axis L physiological saline (fluid)
T Protrusion reference position

Claims (4)

A sheath made of an insulating material;
A support member provided at the distal end of the sheath and formed into a cylindrical shape with a material having electrical insulation;
A shaft-shaped member that is formed of a conductive material and is inserted into the sheath so as to advance and retract;
A pipe line is formed that is connected to the tip of the shaft-like member so as to be able to project and retract through the cylindrical hole of the support member, and is capable of ejecting fluid supplied in the sheath forward, and the shaft-like member. A tubular electrode formed of a conductive material for performing treatment of living tissue by power feeding through;
The shaft-like member or the tubular electrode is provided on the shaft-like member, and is supported when the shaft-like member is moved to the distal end side with respect to the sheath and the tubular electrode is protruded from the tubular hole of the support member to the distal end side. A locking portion for locking to the member;
With
The outer periphery of the tubular electrode when the position of the tubular electrode arranged at the tip of the support member in the axial direction of the sheath is set as a projecting reference position when the locking portion is locked by the support member. A liquid feeding knife, wherein a heat-resistant metal member is provided on a surface in a range including the protruding reference position in the axial direction.   The heat-resistant metal member is provided in a range from the protruding reference position on the outer peripheral surface of the tubular electrode to the protruding reference position in the axial direction by 0.5 mm from the leading end side. Item 2. The liquid-feeding knife according to Item 1.   The liquid-feeding knife according to claim 1, wherein the heat-resistant metal member is made of at least one of tungsten, tantalum, molybdenum, nickel alloy, and titanium. The shaft member is an operation wire,
The liquid feeding knife according to claim 1, wherein a communication hole is formed in the tubular electrode to communicate the internal space of the sheath and the pipe line of the tubular electrode.

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