Treatment tool for endoscope

Abstract

This treatment tool for an endoscope comprises a sheath, a conductive first rod protruding from the tip of the sheath, an insulator fixed to the distal end of the first rod, and a conductive second rod extending distally from the insulator. The position of the second rod on the longitudinal axis of the first rod is fixed with respect to the insulator.

Description

Endoscopic treatment tools

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 620,006, filed Jan. 11, 2024, the entire contents of which are incorporated herein by reference.

[0002] Conventionally, in endoscopic treatments such as ESD (endoscopic submucosal dissection), endoscopic treatment tools such as high-frequency knives have been used, as shown in Patent Document 1. The surgeon preferably performs incisions on biological tissues using endoscopic treatment tools such as high-frequency knives.

[0003] International Publication No. 2014 / 061701

[0004] When performing ESD procedures, it is necessary to frequently change treatment tools depending on the purpose of the treatment. Therefore, conventional high-frequency knives such as those described in Patent Document 1 are required to be multifunctional so that they can easily perform marking on tissue in addition to incising the tissue without changing the treatment tool.

[0005] In consideration of the above circumstances, an object of the present disclosure is to provide an endoscopic treatment tool that allows a variety of treatments to be performed without replacing the treatment tool.

[0006] In order to solve the above problems, the present invention proposes the following means: An endoscopic treatment tool according to a first aspect of the present disclosure includes a sheath, a conductive first rod protruding from a tip of the sheath, an insulator fixed to a distal end of the first rod, and a conductive second rod extending distally from the insulator, wherein the position of the second rod on the longitudinal axis of the first rod is fixed relative to the insulator.

[0007] The endoscopic treatment tool of the present disclosure allows a variety of treatments to be performed without replacing the treatment tool.

[0008] 1 is an overall view of an endoscopic treatment system according to a first embodiment. FIG. 1 is an overall view showing a treatment tool of the endoscopic treatment system. FIG. 2 is a perspective view of a tip portion of the treatment tool. FIG. 3 is a side view of the tip portion of the treatment tool. FIG. 4 is a side view of the tip portion of the treatment tool. FIG. 5 is a cross-sectional view of the tip portion of the treatment tool. FIG. 6 is a view showing an operation unit of the treatment tool. FIG. 7 is a view showing a switch of the operation unit. FIG. 8 is a view showing an incision and dissection step. FIG. 9 is a view showing an incision and dissection step. FIG. 10 is a view showing a modified first rod of the treatment tool. FIG. 11 is a view showing a modified first electrode and a modified insulating tip of the treatment tool. FIG. 12 is a view showing a modified first electrode and a modified insulating tip of the treatment tool. FIG. 13 is a cross-sectional view showing a modified switch. FIG. 14 is a cross-sectional view showing a modified operation wire and a modified connector of the treatment tool. FIG. 15 is a cross-sectional view showing a modified operation wire and a modified connector. FIG. 16 is a cross-sectional view showing another modified operation wire. FIG. 17 is a cross-sectional view showing a modified operation wire. FIG. 18 is a view showing an operation unit of a treatment tool according to a second embodiment. FIG. 19 is a cross-sectional view of the treatment tool when the first rod is retracted. FIG. 19 is a cross-sectional view of the treatment tool when the first rod is protruded. FIG. 19 is a view showing a modified receiving portion of the operation unit and a modified movable portion of the operation unit. FIG. 19 is a view showing a modified receiving portion and a modified movable portion of the operation unit. FIG. 10 is a diagram showing another modified example of the receiving portion. FIG. 11 is a diagram showing another modified example of the receiving portion and another modified example of the movable portion. FIG. 12 is a diagram showing another modified example of the receiving portion and another modified example of the movable portion. FIG. 13 is a diagram showing another modified example of the receiving portion and another modified example of the movable portion. FIG. 14 is a diagram showing another modified example of the receiving portion.

[0009] First Embodiment An endoscopic treatment system 300 according to a first embodiment of the present disclosure will be described with reference to Fig. 1 to Fig. 10. Fig. 1 is an overall view of the endoscopic treatment system 300 according to this embodiment.

[0010] 1, the endoscopic treatment system 300 includes an endoscope 200 and a treatment tool 100. The treatment tool 100 is inserted into the endoscope 200 when in use.

[0011] [Endoscope 200] The endoscope 200 is a known flexible endoscope, and includes an insertion section 202 that is inserted into the body from the tip, and an operation section 207 attached to the base end of the insertion section 202.

[0012] The insertion section 202 has an imaging section 203, a bending section 204, and a flexible section 205. The imaging section 203, the bending section 204, and the flexible section 205 are arranged in this order from the tip of the insertion section 202. A channel 206 for inserting the treatment tool 100 is provided inside the insertion section 202. A tip opening 206a of the channel 206 is provided at the tip of the insertion section 202.

[0013] The imaging unit 203 includes an imaging element such as a CCD or a CMOS, and is capable of capturing an image of the site to be treated. The imaging unit 203 can capture an image of the distal end of the treatment tool 100 when the treatment tool 100 protrudes from the distal end opening 206 a of the channel 206.

[0014] The bending portion 204 bends in accordance with the operator's operation of the operating portion 207. The flexible portion 205 is a flexible tubular portion.

[0015] The operation unit 207 is connected to the flexible section 205. The operation unit 207 has a grip 208, an input unit 209, a proximal end opening 206b of the channel 206, and a universal cord 210. The grip 208 is a part that is held by an operator. The input unit 209 accepts an operation input for bending the bending section 204.

[0016] The universal cord 210 includes a video signal line for externally outputting the image captured by the imaging unit 203. The video signal line is connected to a display device such as a liquid crystal display via an image processing device including a processor or the like.

[0017] [Treatment Tool 100] Figure 2 is an overall view showing the treatment tool 100. The treatment tool (endoscopic treatment tool, high-frequency treatment tool) 100 is an ESD knife. The treatment tool 100 includes a sheath 1, a knife 2, an insulating tip 3, a control wire (first wire) 41 (see Figure 4), a current-carrying wire (second wire) 42 (see Figure 6), and an operation unit 5. The knife 2 and the insulating tip 3 constitute a "treatment unit 110" that treats an affected area. In the following description, in the longitudinal axis direction (longitudinal direction, axial direction) A of the treatment tool 100, the side that is inserted into the patient's body is referred to as the "tip side (distal side) A1," and the side of the operation unit 5 is referred to as the "base side (proximal side) A2."

[0018] The sheath 1 is a long tubular member extending from a distal end 1a to a proximal end 1b. The sheath 1 can be inserted into a channel 206 of the endoscope 200 and can move forward and backward through the channel 206. As shown in Fig. 1, when the sheath 1 is inserted into the channel 206, the distal end 1a of the sheath 1 can protrude and retract from a distal end opening 206a of the channel 206.

[0019] 3 is a perspective view of the distal end portion of the treatment tool 100. The sheath 1 has an outer tube 10 extending in the longitudinal axis direction A and a distal end member 11 provided at the distal end of the outer tube 10. Note that the sheath 1 may be formed by integrally molding the outer tube 10 and the distal end member 11.

[0020] The tip member 11 is formed in a cylindrical shape. Note that "cylindrical" includes not only a strict cylindrical shape but also a shape close to a cylindrical shape. The tip member 11 is preferably formed of an insulating material such as a resin. Examples of the resin forming the tip member 11 include PTFE, PEEK, and zirconia-based ceramics. A through hole 12 is formed in the tip member 11.

[0021] The through hole 12 is a hole provided in the distal end member 11 and passes through the distal end member 11 in the longitudinal axis direction A. The distal end of the through hole 12 communicates with a first opening 12a formed in a distal end surface 14 of the distal end member 11. The proximal end of the through hole 12 communicates with an internal space 19 of the outer tube 10.

[0022] 4 and 5 are side views of the distal end of the treatment tool 100. The knife (electrode) 2 is a metal member. The knife 2 is formed of a material such as stainless steel. The knife 2 is conductive and is energized with high-frequency current. The knife 2 has a first rod 20, a first electrode 21, a connector 22, and a second rod 23.

[0023] The central axis O2 of the knife 2 in the longitudinal axis direction A preferably coincides with the central axis O1 of the sheath 1 in the longitudinal axis direction A. Note that "coinciding" includes not only a state in which they coincide exactly but also a state in which they almost coincide.

[0024] 6 is a cross-sectional view of the distal end of the treatment tool 100. The first rod (blade, electrode body) 20 is a round rod-shaped member made of conductive metal. Note that "round rod-shaped" includes not only a strict round rod shape but also a shape close to a round rod shape. The first rod 20 is hollow and has an internal space 20s that penetrates the first rod 20 in the longitudinal axis direction A. The first rod 20 is disposed on the distal side A1 of the sheath 1. A manipulation wire 41 is attached to the proximal end of the first rod 20.

[0025] The first rod 20 is inserted through the through-hole 12 of the distal end member 11 of the sheath 1 along the longitudinal axis direction A, and is capable of freely protruding and retracting from the first opening 12 a to the distal end side A1. Note that the first rod 20 may be fixed in a state where it protrudes from the first opening 12 a to the distal end side A1 and is unable to advance or retreat.

[0026] The first electrode (flange, expanded diameter portion) 21 is a disc-shaped conductive member provided at the tip of the first rod 20. The first electrode 21 is not limited to a disc shape, and may be formed in a radial shape extending radially outward in the radial direction R from the central axis O2 of the rod 20. A flat base end surface (back surface) 21b is formed on the base end side A2 of the first electrode 21. The base end surface 21 is not limited to a flat surface, and may be, for example, an uneven surface. The knife 2 may not have the first electrode 21.

[0027] The connector (connecting member) 22 is a cylindrical member made of metal. Note that "cylindrical" includes not only a strictly cylindrical shape but also a shape close to a cylindrical shape. The connector 22 is provided with a through-hole 22b that penetrates in the radial direction R. The connector 22 connects the first rod 20 and the operation wire 41. For example, the first rod 20 and the operation wire 41 are connected by brazing using solder inserted through the through-hole 22b.

[0028] The second rod (second electrode) 23 is a conductive metal member. The second rod 23 extends from the insulating tip 3 to the distal side A1. The proximal end of the proximal end portion 23b of the second rod 23 is connected to the current-carrying wire 42 and fixed to the insulating tip 3 by adhesive or press-fitting. The second rod 23 cannot move forward or backward relative to the insulating tip 3, and its position on the longitudinal axis of the first rod 20 is fixed. As shown in FIG. 4 , the length L2 from the distal end of the insulating tip 3 to the distal end of the second rod 23 is shorter than the protruding length L1 of the first rod 20 from the sheath 1 when the first rod 20 is protruded to the distal side A1 to the maximum.

[0029] The second rod 23 has a tip portion (flange, enlarged diameter portion) 23a disposed on the tip side A1 and a base end portion 23b disposed on the base side A2. The tip portion 23a and the base end portion 23b are arranged and connected in the longitudinal axis direction A. The tip portion 23a and the base end portion 23b are formed in a cylindrical shape. The outer diameter of the tip portion 23a is larger than the outer diameter of the base end portion 23b. The tip portion 23a has a flange shape (disk shape). Note that the shape of the tip portion 23a is not limited to a flange shape and may be, for example, a triangular shape or a hook shape.

[0030] The outer diameter of at least a part of the second rod 23 is equal to or smaller than the outer diameter of the first rod 20. In this embodiment, the outer diameter of the base end 23b of the second rod 23 is smaller than the outer diameter of the first rod 20. Note that the outer diameter of the tip end 23a of the second rod 23 may be smaller than the outer diameter of the first rod 20.

[0031] The first rod 20 and the first electrode 21 are disposed on either side of the insulating tip 3 in the longitudinal axis direction A, and the second rod 23 is disposed electrically separated from the insulating tip 3 .

[0032] A high-frequency current is supplied to the first rod 20 and the first electrode 21 from a manipulation wire (first wire) 41 connected to the manipulation unit 5. When a high-frequency current is supplied to the first rod 20 and the first electrode 21 from the manipulation wire 41, the first rod 20 and the first electrode 21 function as a monopolar electrode that outputs the high-frequency current to the biological tissue.

[0033] A high-frequency current is supplied to the second rod 23 from a current-carrying wire (second wire) 42 connected to the operation unit 5. When a high-frequency current is supplied to the second rod 23 from the current-carrying wire 42, the second rod 23 functions as a monopolar electrode that outputs the high-frequency current to the biological tissue.

[0034] 4, when the knife 2 is advanced relative to the sheath 1, the tip of the connector 22 comes into contact with the tip member 11. When the tip of the connector 22 comes into contact with the tip member 11, the knife 2 is positioned at a first position P1, which is the position on the tip-most side A1.

[0035] 5, when the knife 2 is retracted relative to the sheath 1, the proximal end surface 21b of the first electrode 21 comes into contact with the distal end surface 14 of the distal end member 11. The contact between the proximal end surface 21b of the first electrode 21 and the distal end member 11 positions the knife 2 at the second position P2, which is the position closest to the proximal end side A2.

[0036] The knife 2 can be advanced and retreated from the first position P1 to the second position P2 by advancing and retreating the operating wire 41. The knife 2 may be fixed so as not to be able to advance and retreat in a state where it protrudes from the first opening 12a to the distal end side A1.

[0037] 4 , by moving the knife 2 closer to the first position P1, a rear space SR can be secured on the proximal side A2 of the first electrode 21. By securing the rear space SR of the first electrode 21, the surgeon can preferably perform an incision procedure using the first electrode 21.

[0038] The insulating tip (insulator) 3 is made of an insulating material such as ceramic or resin. The insulating tip 3 is provided on the distal side A1 of the first electrode 21. In this embodiment, the base end of the insulating tip 3 is fixed to the distal end of the first rod 20 while in contact with the first electrode 21. In a front view seen from the direction along the longitudinal axis A, the outer periphery of the first electrode 21 is positioned more inward in the radial direction R than the outer surface 31 of the insulating tip 3 along its entire circumference. The insulating tip 3, the first rod 20, and the second rod 23 can be moved forward and backward together with respect to the sheath 1.

[0039] The central axis O3 of the insulating tip 3 in the longitudinal axis direction A preferably coincides with the central axis O1 of the sheath 1 in the longitudinal axis direction A. Note that "coinciding" includes not only a state in which they coincide exactly but also a state in which they almost coincide.

[0040] The insulating tip 3 has a main body 30, a distal end 32 disposed on the distal end side A1 of the main body 30, and a proximal end 33 disposed on the proximal end side A2 of the main body 30. The distal end 32, the main body 30, and the proximal end 33 are aligned and connected in the longitudinal axis direction A.

[0041] The main body 30 is formed in a cylindrical shape. The central axis of the longitudinal axis direction A of the tip portion 32 coincides with the central axis O3.

[0042] The tip portion 32 is provided at the tip of the main body portion 30. The tip portion 32 is formed in a hemispherical (dome) shape, and the diameter thereof decreases toward the tip side A1.

[0043] The base end portion 33 is provided at the base end of the main body portion 30. The base end portion 33 is formed in a hemispherical (dome) shape, and the diameter thereof decreases toward the base end side A2.

[0044] The operation wire 41 is a metal wire that passes through the internal space (duct, lumen) 19 of the outer tube 10. The operation wire 41 is formed of a material such as stainless steel. The operation wire 41 is hollow and has an internal space 41s that passes through the operation wire 41 in the longitudinal axis direction A. The tip of the operation wire 41 is connected to the first rod 20, and the internal space 41s of the operation wire 41 communicates with the internal space 20s of the first rod 20. The base end of the operation wire 41 is connected to the operation unit 5.

[0045] The current-carrying wire 42 is a metal wire. The current-carrying wire 42 is inserted through the internal space 41s of the operation wire 41 and the internal space 20s of the first rod 20. An insulating coating 42a is provided on the outer periphery of the current-carrying wire 42, and the current-carrying wire 42 is insulated from the operation wire 41 and the first rod 20. The insulating coating 42a is stripped from a tip end 42b of the current-carrying wire 42, and the tip end 42b is connected to the second rod 23 by brazing or the like.

[0046] The current-carrying wire 42 may be thickened to increase its rigidity so that it can be advanced and retreated, and the second rod 23 may be able to advance and retreat freely relative to the insulating tip 3 and the first rod 20 in accordance with the advance and retreat of the current-carrying wire 42 .

[0047] 7 is a diagram showing the operation unit 5. The operation unit 5 has an operation unit main body 51, a slider 52, a power supply connector 53, and a switch 55.

[0048] The distal end of the operation portion main body 51 is connected to the proximal end 1b of the sheath 1. The operation portion main body 51 has an internal space through which the operation wire 41 can be inserted. The operation wire 41 passes through the internal space 19 of the outer tube 10 and the internal space of the operation portion main body 51 and extends to the slider 52.

[0049] The slider (handle) 52 is attached to the operation unit body 51 so as to be movable along the longitudinal axis direction A. The proximal end of the operation wire 41 is attached to the slider 52. When the surgeon moves the slider 52 forward or backward relative to the operation unit body 51, the operation wire 41, the knife 2, and the insulating tip 3 move forward or backward.

[0050] The power feed connector 53 is fixed to the slider 52. The power feed connector 53 can be connected to a high-frequency power supply device (not shown) via an electric cable. The power feed connector 53 can supply high-frequency current supplied from the high-frequency power supply device to the first rod 20 and the first electrode 21 via the operation wire 41. The power feed connector 53 can also supply high-frequency current supplied from the high-frequency power supply device to the second rod 23 via the current-carrying wire 42. The power feed connector 53 may be fixed to the operation unit main body 51 instead of the slider 52.

[0051] 8 is a diagram showing the switch 55. The switch 55 is provided on the slider 52. The switch 55 is a switch that alternatively selects one of the operation wire 41 and the current-carrying wire 42 as the current path, and has a connection pad 55p attached to it. The connection pad 55p and the power supply connector 53 are connected by a metal wire or the like. In other words, the high-frequency current supplied from the power supply connector 53 is passed through only one of the wires selected by the switch 55.

[0052] The switch 55 has a connection pad 55p electrically connected to the power supply connector 53. The switch 55 is slidable between a first position S1, where the connection pad 55p is electrically connected to the conductive wire 41e, and a second position S2, where the connection pad 55p is electrically connected to the current-carrying wire 42. The conductive wire 41e is a wire electrically connected to the operation wire 41. Note that the conductive wire 41e is not essential, and the operation wire 41 may extend to the connection pad 55p. In that case, when the switch 55 is located in the first position S1, the operation wire 41 is electrically connected directly to the connection pad 55p.

[0053] When the switch 55 is in the first position S1, the high-frequency current supplied from the power supply connector 53 is supplied to the first rod 20 and the first electrode 21 via the operation wire 41. When the switch 55 is in the second position S2, the high-frequency current supplied from the power supply connector 53 is supplied to the second rod 23 via the current-carrying wire 42.

[0054] [Method of Using the Endoscopic Treatment System 300] Next, a procedure using the endoscopic treatment system 300 of this embodiment (method of using the endoscopic treatment system 300) will be described. Specifically, an incision and dissection treatment of a lesion in an endoscopic treatment such as ESD (endoscopic submucosal dissection) will be described.

[0055] As a preparatory step, the surgeon identifies the lesion by a known method. Specifically, the surgeon inserts the insertion section 202 of the endoscope 200 into the digestive tract (e.g., the esophagus, stomach, duodenum, or large intestine) and identifies the lesion while observing an image obtained by the imaging section 203 of the endoscope.

[0056] <Insertion Step> The surgeon inserts the treatment tool 100 into the channel 206, and causes the distal end 1 a of the sheath 1 to protrude from the distal end opening 206 a of the insertion portion 202. The surgeon advances the slider 52 of the operation portion 5 relatively to the operation portion body 51, and causes the knife 2 and the insulating tip 3 to protrude.

[0057] <Marking Step> Figure 9 is a diagram showing the marking step. The surgeon retracts the slider 52 of the operating unit 5 relative to the operating unit body 51, positioning the knife 2 at the proximal side A2 (e.g., second position P2). With the second rod 23 in contact with the mucosal surface, the surgeon moves the switch 55 to the second position S2 to energize the second rod 23, thereby cauterizing and coagulating the biological tissue (mucosal surface) around the lesion. As a result, a marking M is applied to the mucosal surface. The surgeon may also cauterize and coagulate the biological tissue (mucosal surface) using the first electrode 21. Note that marking M on the biological tissue differs from incision in that the biological tissue (mucosal surface) is simply denatured by coagulating it.

[0058] <Incision and Dissection Step> Figure 10 is a diagram showing the incision and dissection step. Next, the surgeon performs the incision and dissection procedure. With the second rod 23 submerged under the mucosal layer, the surgeon moves the switch 55 to the second position S2 to energize the second rod 23, thereby creating a pre-cut (an entry point for starting the incision) P in the mucosal layer and / or submucosal layer.

[0059] The surgeon advances the slider 52 of the operation unit 5 relative to the operation unit body 51 to position the knife 2 on the distal end side A1 (e.g., first position P1). The surgeon moves the switch 55 to first position S1 to apply high-frequency current to the first rod 20, and then moves the first rod 20 from the pre-cut P to incise the mucosa at the lesion. As shown in FIG. 10 , with high-frequency current applied to the first rod 20, the surgeon lifts the mucosa at the incised lesion to expose the submucosal layer, and then peels the submucosal layer at the incised lesion. At this time, because high-frequency current is not applied to the second rod 23, the second rod 23 does not incise tissues such as the mucosa or submucosa.

[0060] The surgeon continues the above-mentioned operations (treatments) as necessary, and finally excises the lesion, completing the ESD procedure.

[0061] According to the treatment tool 100 of this embodiment, in addition to incising biological tissue, marking of biological tissue can also be easily performed without changing the treatment tool. The surgeon can supply high-frequency current to only one of the first rod 20 and the second rod 23 by operating the switch 55 according to the treatment to be performed.

[0062] Although the first embodiment of the present disclosure has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment and includes design modifications within the scope of the present disclosure. Furthermore, the components shown in the above-described embodiment and modified examples can be configured by appropriately combining them.

[0063] (Variation 1) Fig. 11 is a diagram showing a first rod 20A, which is a variation of the first rod 20. The base end side of the first rod 20A protruding from the sheath 1 is covered with an insulating member 20i. The insulating member 20i is, for example, an insulating coating or an insulating tube. Since electricity is not passed through at least a portion of the outer circumferential surface of the first rod 20A to the biological tissue, thermal invasion of the biological tissue can be suppressed.

[0064] 12 and 13 show a first electrode 21A, which is a modification of the first electrode 21, and an insulating tip 3A, which is a modification of the insulating tip 3. The first electrode 21A is a plate-shaped conductive member provided at the tip of the first rod 20. The first electrode 21A has a protrusion 21p extending in a direction intersecting the longitudinal axis of the first rod 20. For example, the protrusion 21p protrudes outward in the radial direction R of the first rod 20 beyond the outer surface of the base end of the insulating tip 3A (the base end of a tapered surface 33t described below). A planar base end surface (back surface) 21b is formed on the base end side A2 of the first electrode 21A. The base end surface 21b is not limited to a planar surface and may, for example, be an uneven surface.

[0065] The first electrode 21A has three protrusions 21p. The three protrusions 21p are arranged at equal intervals along the circumferential direction C relative to the longitudinal axis direction A. In a front view seen from the direction along the longitudinal axis direction A, the first electrode 21A is formed in a trifurcated shape. The first electrode 21A may also be formed in a four- or five-pronged shape. That is, the first electrode 21A may be formed in a radial shape extending radially outward in the radial direction R from the central axis O2 of the rod 20. The first electrode 21A may also be formed in a flange shape such as a disk shape or a polygonal shape.

[0066] The insulating tip (insulator) 3A is made of an insulating material such as ceramic or resin. The insulating tip 3A is provided on the distal side A1 of the first electrode 21A. The base end of the insulating tip 3A is fixed to the first rod 20 while in contact with the first electrode 21A. At least the protrusion 21p of the first electrode 21A protrudes outward in the radial direction R from the outer peripheral surface of the base end of the insulating tip 3A (the base end of a tapered surface 33t described later).

[0067] In a front view seen from the longitudinal axis direction A, a maximum distance D1 from the central axis of the second rod 23 to the outer surface of the second rod 23 is shorter than a distance D2 from the central axis of the first rod 20 to the top 21t of the protrusion 21p of the first electrode 21A.

[0068] The insulating tip 3A has a main body 30, a distal end 32, and a proximal end 33A, which is a modified version of the proximal end 33. The proximal end 33A has a tapered surface 33t that narrows in diameter toward the first electrode 21A (toward the proximal side A2). The tapered surface 33t is spaced apart from the protruding portion 21p with a gap therebetween, and a forward space (gap) SF is formed between the tapered surface 33t and the protruding portion 21p. That is, the tapered surface 33t and the protruding portion 21p are spaced apart with a gap in the longitudinal axis direction A of the first rod 20, and are disposed so that the tapered surface 33t faces the distal end surface of the protruding portion 21p. By ensuring the forward space (gap) SF of the first electrode 21A, the surgeon can preferably perform incision procedures, etc., using the first electrode 21A.

[0069] 14 is a cross-sectional view showing a switch 55A that is a modification of the switch 55. The switch 55A can be moved by rotation about a rotation axis RO, rather than by sliding, between a first position S1 where the connection pad 55p is connected to the conductive wire 41e and a second position S2 where the connection pad 55p is connected to the current-carrying wire 42.

[0070] 15 and 16 are cross-sectional views showing an operation wire 41A that is a modification of the operation wire 41 and a connector 22A that is a modification of the connector 22. Unlike the hollow operation wire 41, the operation wire 41A is solid. The connector 22A has a through-hole 22c that penetrates in the radial direction R. The current-carrying wire 42 that passes through the internal space 20s of the first rod 20 passes through the through-hole 22c of the connector 22A and then passes through the internal space 19 of the outer tube 10.

[0071] The proximal end of the operation wire 41A is connected by a connector 22A to a hollow metal pipe 43. The high-frequency current supplied to the conductive wire 41e is supplied to the first rod 20 and the first electrode 21 via the metal pipe 43 and the operation wire 41A.

[0072] The base end of the current-carrying wire 42 passes through the through-hole 22c of the connector 22A and is inserted into the internal space 43s of the metal pipe 43. The current-carrying wire 42 extends through the internal space 43s of the metal pipe 43 to the slider 52.

[0073] The current-carrying wire 42 may be inserted through the brazing through-hole 22b instead of the through-hole 22c of the connector 22A. The through-hole 22b is blocked by pouring brazing material into it while the current-carrying wire 42 is inserted through the through-hole 22b. In this case, the internal space 19 of the sheath 1 and the internal space 20s of the rod 20 are not in communication with each other.

[0074] 17 and 18 are cross-sectional views showing an operating member 41B, which is a modified example of the operating wire 41. The operating member 41B is a long, solid member made of resin or the like and has no electrical conductivity. The connector 22A on the distal end side A1 and the connector 22A on the proximal end side A2 are electrically connected by a conductive wire 44. An insulating coating 44a is provided on the outer periphery of the conductive wire 44. A high-frequency current supplied to the conductive wire 41e is supplied to the first rod 20 and the first electrode 21 via the metal pipe 43 and the conductive wire 44.

[0075] Second Embodiment A treatment tool 100C according to a second embodiment of the present disclosure will be described with reference to Fig. 19 to Fig. 21. In the following description, configurations common to those already described will be assigned the same reference numerals, and duplicate description will be omitted.

[0076] The treatment tool (endoscopic treatment tool, high-frequency treatment tool) 100C is an ESD knife. The treatment tool 100C includes a sheath 1, a knife 2, an insulating tip 3, an operating wire 41, a current-carrying wire 42, and an operating section 5C.

[0077] 19 is a diagram showing the operation unit 5C, which includes an operation unit main body 51, a slider 52, a power supply connector 53, and a switch 55C.

[0078] The switch 55C is a switch that selectively selects one of the operation wire 41 and the current-carrying wire 42 as a current-carrying path in accordance with the advancement and retreat of the slider 52. The switch 55C has a receiving portion 56 and a movable portion 57.

[0079] The receiving portion 56 is a conductive member fixed to the operation unit main body 51 and electrically connected to the power supply connector 53. A recess 56a is formed in the receiving portion 56 to accommodate the movable portion 57. The recess 56a opens toward the distal end side A1 and accommodates the movable portion 57, which retracts toward the proximal end side A2. A plug 56p protruding toward the distal end side A1 is provided on a bottom surface 56b formed on the proximal end side A2 of the recess 56a. The plug 56p is formed in a conical shape. An insulating member 56c is provided on the bottom surface 56b of the recess 56a other than the plug 56p and on an inner surface 56s of the recess 56a on the proximal end side A2.

[0080] The movable part 57 is a conductive member fixed to the proximal end of the operation wire 41, and moves forward and backward along the longitudinal axis direction A in response to the forward and backward movement of the slider 52. A plug receiving part 57a is formed at the end of the proximal side A2 of the movable part 57. The plug receiving part 57a is electrically connected to the current-carrying wire 42. A conical recess is formed in the plug receiving part 57a, and the plug 56p can be engaged with the plug 56p. When the movable part 57 is accommodated in the receiving part 56, the plug 56p and the plug receiving part 57a are engaged with each other. The plug receiving part 57a is covered with an insulating member 57b, except for the portion electrically connected to the current-carrying wire 42 and the portion that engages with the plug 56p.

[0081] An insulating member 41c is provided on the outer surface 41e of the operation wire 41 at a proximal end portion other than the proximal end portion 41b. Here, the proximal end portion 41b is the portion of the proximal end portion of the outer surface 41e of the operation wire 41 that is closest to the proximal end side A2.

[0082] 20 is a cross-sectional view of the treatment tool 100C when the first rod 20 is retracted. The surgeon moves the slider 52 to the proximal side A2 to retract the first rod 20 into the sheath 1. When the movable portion 57 is housed in the receiving portion 56, the plug 56p and the plug receiving portion 57a ​​engage with each other. High-frequency current supplied from the power supply connector 53 is supplied to the second rod 23 via the plug 56p, the plug receiving portion 57a, and the current-carrying wire 42.

[0083] 21 is a cross-sectional view of the treatment tool 100C when the first rod 20 is protruded. The surgeon moves the slider 52 to the distal side A1 to protrude the first rod 20 from the sheath 1. The proximal end 41b of the operation wire 41 comes into contact with the uninsulated inner surface 56s. High-frequency current supplied from the power supply connector 53 is supplied to the first rod 20 and the first electrode 21 via the inner surface 56s, the proximal end 41b, and the operation wire 41.

[0084] The treatment tool 100C according to this embodiment allows for easy marking of biological tissue in addition to incision without changing the treatment tool. The surgeon can supply high-frequency current to either the first rod 20 or the second rod 23 by advancing or retracting the insulating tip 3, first rod 20, and second rod 23 relative to the sheath 1. As shown in Fig. 20 , the surgeon can supply high-frequency current only to the second rod 23 by moving the insulating tip 3, first rod 20, and second rod 23 toward the proximal end side A2. As shown in Fig. 21 , the surgeon can supply high-frequency current only to the first rod 20 and the first electrode 21 by moving the first rod 20 and second rod 23 toward the distal end side A1.

[0085] Although the second embodiment of the present disclosure has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment and includes design modifications within the scope of the present disclosure. Furthermore, the components shown in the above-described embodiment and modified examples can be configured by appropriately combining them.

[0086] 22 and 23 show a receiving portion 56A, which is a modified example of the receiving portion 56, and a movable portion 57A, which is a modified example of the movable portion 57. A plug receiving portion 56d recessed toward the base end side A2 is provided on the bottom surface 56b of the receiving portion 56A. A plug 57p is formed on the end of the base end side A2 of the movable portion 57A. When the movable portion 57A is accommodated in the receiving portion 56A, the plug 57p and the plug receiving portion 56d engage with each other.

[0087] The plug receiving portion 56d is provided with a leaf spring 56e. The plug 57p accommodated in the plug receiving portion 56d is inserted while pushing and spreading the leaf spring 56e, thereby stabilizing the electrical contact between the plug 57p and the plug receiving portion 56d.

[0088] (Variation 2-2) FIG. 24 shows a receiving portion 56B, which is a variation of the receiving portion 56A. The receiving portion 56B has a protrusion 56t that protrudes inward in the radial direction R on an inner surface 56s where the insulating member 56c is not provided. The protrusion 56t is provided, for example, on the distal-most side A1 of the inner surface 56s. The support portion 56u on which the protrusion 56t is provided is formed in a cantilever shape and is elastically deformable in the radial direction R. When the movable portion 57A is inserted into the receiving portion 56B, the movable portion 57A pushes and spreads the protrusion 56t. This stabilizes the electrical contact between the proximal end 41b and the inner surface 56s. The protrusion 56t may be a ball plunger.

[0089] (Variation 2-3) Figure 25 shows a receiving portion 56C, which is a variation of the receiving portion 56, and a movable portion 57C, which is a variation of the movable portion 57. The receiving portion 56C and the movable portion 57C do not have the plug 56p and the plug receiving portion 57a. The bottom surface 56b of the receiving portion 56C and the movable portion 57C contact each other via the conductive spring 58. Because the contactable range is expanded, the electrical contact between the bottom surface 56b of the receiving portion 56C and the movable portion 57C is stabilized.

[0090] 26 to 28 show a receiving portion 56D, which is a modified example of the receiving portion 56, and a movable portion 57D, which is a modified example of the movable portion 57. The receiving portion 56D does not have a plug 56p. The movable portion 57D is formed in a cylindrical shape and does not have a plug receiving portion 57a ​​or an insulating member 57b. The movable portion 57D is electrically connected to the receiving portion 56D by contacting the inner surface 56s and bottom surface 56b of the receiving portion 56D. An insulating member 56f is provided on the inner surface 56s of the receiving portion 56D in a middle portion in the longitudinal axis direction A.

[0091] 27 , by moving the slider 52 to the base end side A2 and accommodating the movable part 57D in the base end side A2 of the receiving part 56D, the movable part 57D engages with the inner surface 56s and the bottom surface 56b. The high-frequency current supplied from the power supply connector 53 is supplied to the second rod 23 via the receiving part 56D, the movable part 57D, and the current-carrying wire 42.

[0092] 28 , by moving the slider 52 toward the distal side A1 and moving the movable part 57D toward the distal side A1 of the receiving part 56D, the movable part 57D, the inner surface 56s, and the most proximal end 41b engage with each other. The high-frequency current supplied from the power supply connector 53 is supplied to the first rod 20 and the first electrode 21 via the inner surface 56s, the most proximal end 41b, and the operation wire 41.

[0093] Since the receiving portion 56D and the movable portion 57D can ensure a long contactable portion in the longitudinal axis direction A, the electrical contact between the receiving portion 56D and the movable portion 57D is stabilized even if the length of the sheath 1 changes due to bending of the sheath 1.

[0094] (Variation 2-5) FIG. 29 illustrates a receiving portion 56E, a variation of the receiving portion 56D. The receiving portion 56E has two protrusions 56t that protrude inward in the radial direction R from the inner surface 56s where the insulating member 56c is not provided. One of the protrusions 56t is located on the distal end side A1 of the insulating member 56f. The other protrusion 56t is located on the proximal end side A2 of the insulating member 56f. In a front view taken along the longitudinal axis A, the two protrusions 56t are located on both sides of the central axis O5 of the recess 56a. As with the receiving portion 56B, the electrical contact between the proximal end portion 41b and the inner surface 56s is stabilized. Furthermore, because the protrusion 56t on the proximal end side A2 contacts the movable portion 57D, the electrical contact between the movable portion 57D and the inner surface 56s is also stabilized. Note that the protrusions 56t may be ball plungers.

[0095] The present disclosure can be applied to an endoscopic treatment tool.

[0096] 300 Endoscopic treatment system 200 Endoscope 100, 100C Treatment tool (endoscopic treatment tool, high-frequency treatment tool) 110 Treatment section 1 Sheath 10 Outer tube 11 Distal end member 12 Through hole 12a First opening 14 Distal end surface 19 Internal space (duct, lumen) 2 Knife (electrode) 20, 20A First rod (blade, electrode body) 20 First rod 20i Insulating member 20s Internal space 21, 21A First electrode (flange, enlarged diameter portion) 21b Base end surface (rear surface) 21p Projection 22, 22A Connector (coupling member) 22b Through hole 22c Through hole 23 Second rod (second electrode) 23a Distal end portion (flange, enlarged diameter portion) 23b Base end portion 3, 3A Insulating tip (insulator) 30 Main body 31 Outer surface 32 Tip portion 33, 33A Base end portion 33t Tapered surface 41, 41A Operation wire 41e Conductive wire 41b Basemost end portion 41B Operation member 41c Insulating member 41e Outer surface 41s Internal space 42 Current-carrying wire 42a Insulating coating 42b Tip portion 43 Metal pipe 43s Internal space 44 Conductive wire 44a Insulating coating 5, 5C Operation unit 51 Operation unit body 52 Slider (handle) 53 Power supply connector 55, 55A, 55C Switch 55p Connection pad 56, 56A, 56B, 56C, 56D, 56E Receiving portion 56a Recess 56b Bottom surface 56c Insulating member 56d Plug receiving portion 56e Leaf spring 56f Insulating member 56p Plug 56s Inner surface 56t Protrusion 56u Support portion 57, 57A, 57C, 57D Movable portion 57a ​​Plug receiving portion 57b Insulating member 57p Plug 58 Spring A Longitudinal axis direction (longitudinal direction, axial direction) A1 Tip side (distal side) A2 Base side (proximal side) C Circumferential direction P1 First position P2 Second position R Radial direction S1 First position S2 Second position SF Front space SR Rear space

Claims

1. A treatment instrument for an endoscope, comprising a sheath, a conductive first rod protruding from the tip of the sheath, an insulator fixed to the distal end of the first rod, and a conductive second rod extending distally from the insulator, wherein the position of the second rod on the longitudinal axis of the first rod with respect to the insulator is fixed.

2. The treatment instrument for an endoscope according to claim 1, wherein the outer diameter of at least a part of the second rod is equal to or less than the outer diameter of the first rod.

3. The treatment instrument for an endoscope according to claim 1, wherein the length from the tip of the insulator to the tip of the second rod is smaller than the protruding length of the first rod from the sheath.

4. The treatment instrument for an endoscope according to claim 1, wherein the second rod is fixed to the insulator.

5. The treatment instrument for an endoscope according to claim 1, wherein the second rod is connected to a conductive wire passing through the inside of the first rod.

6. The treatment instrument for an endoscope according to claim 1, further comprising a switch for selecting one of the first rod and the second rod as an energization path.

7. The treatment instrument for an endoscope according to claim 6, wherein a handle is provided at the proximal end portion of the sheath, and the switch is provided on the handle.

8. The treatment instrument for an endoscope according to claim 6, wherein the insulator, the first rod, and the second rod are configured to be integrally movable forward and backward with respect to the sheath, and the switch can select one of the first rod and the second rod as the energization path according to the forward and backward movement of the first rod.

9. The treatment instrument for an endoscope according to claim 6, wherein the insulator, the first rod, and the second rod are configured to be integrally movable forward and backward with respect to the sheath, and the switch can select one of the first rod and the second rod as the energization path independently of the forward and backward movement of the first rod.

10. The treatment instrument for an endoscope according to claim 1, wherein the proximal end side of the first rod protruding from the sheath is covered with an insulating member.

11. The treatment instrument for an endoscope according to claim 1, having an electrode connected to the tip of the first rod, wherein the insulator is provided distally of the electrode, and a part of the electrode protrudes radially outward of the first rod from the outer surface at the proximal end of the insulator.

12. The electrode has a protruding portion that protrudes radially outward of the first rod beyond the outer surface at the proximal end of the insulator. In a front view seen from the longitudinal axis direction, the maximum distance from the central axis of the second rod to the outer surface of the second rod is smaller than the distance from the central axis of the first rod to the top of the protruding portion of the electrode. The endoscopic treatment instrument according to claim 11.

13. A sheath, a conductive first rod protruding from the distal end of the sheath, an insulator provided at the distal end of the first rod, and a conductive second rod extending distally from the insulator. The insulator, the first rod, and the second rod are configured to be integrally movable forward and backward with respect to the sheath between a first position where the first rod is advanced to the maximum extent and a second position where the first rod is retracted to the maximum extent. An endoscopic treatment instrument.

14. The length from the distal end of the insulator to the distal end of the second rod is smaller than the maximum protruding amount of the first rod from the sheath. The endoscopic treatment instrument according to claim 13.

15. A sheath, a conductive first rod protruding from the distal end of the sheath, an insulator provided at the distal end of the first rod, a conductive second rod extending distally from the insulator, and a switch for selecting one of the first rod and the second rod as an energization path. An endoscopic treatment instrument.

16. The second rod is connected to a conductive wire passing through the inside of the first rod. The endoscopic treatment instrument according to claim 15.

17. The proximal end portion of the sheath has a handle, and the switch is provided on the handle. The endoscopic treatment instrument according to claim 15.

18. The switch can select one of the first rod and the second rod as the energization path according to the forward and backward movement of the first rod. The endoscopic treatment instrument according to claim 15.

19. The insulator, the first rod, and the second rod are configured to be integrally movable forward and backward with respect to the sheath. The endoscopic treatment instrument according to claim 15.

20. The second rod is configured to be movable forward and backward with respect to the insulator and the first rod. The endoscopic treatment instrument according to claim 15.

Images