JP7442252B2 - Endoscopic electrocautery dissection tool - Google Patents

Description

The present invention provides an electrocautery for an endoscope that has a distal treatment section that is inserted into and removed from a channel of an endoscope and inserted into a body cavity together with an insertion section of the endoscope to perform treatments such as incision of a diseased part of living tissue. Concerning incision tools.

The electrocautery incision tool for an endoscope has a distal treatment section at the distal end of the sheath, the sheath is housed in a channel of the endoscope so that it can be inserted and removed, and the sheath is inserted into the body cavity together with the insertion section of the endoscope. The distal treatment section that extends from the tip of the endoscope's insertion section within the field of view of the endoscope allows for the treatment of diseased areas within body cavities (removal of affected areas of living tissue, sample collection, resection, hemostasis, etc.). Used to perform invasive procedures.

Endoscopic submucosal dissection (hereinafter referred to as "endoscopic submucosal dissection") is a method that can reliably remove a wide range of lesions such as early esophageal cancer, early gastric cancer, and early colorectal cancer using an endoscope. , is known as "ESD").

ESD is a treatment method in which a wide range of lesions is removed all at once.The ESD technique consists of (1) marking the excision area of the lesion (marking), and (2) locally injecting a medicinal solution into the submucosal layer to remove the mucosa. The lesion area is raised (local injection), (3) the area around the mucosal lesion is incised according to the markings, and the submucosal layer is peeled off (incision/exfoliation). It consists of procedures (processes) such as stopping bleeding (hemostasis).

A dedicated disposable endoscopic treatment tool is used in each step of ESD. For example, in the incision/exfoliation process, an endoscopic treatment tool is used that is equipped with a needle knife or the like that applies a high-frequency current to cut away mucous membranes and the like. In ESD procedures, bleeding is often involved when removing mucous membranes and the like. If bleeding occurs during a procedure, the surgeon must remove the endoscopic treatment tool for incision and dissection from the endoscope, replace it with the endoscopic treatment tool for hemostasis, and perform endoscopic hemostasis. need to be done.

Japanese Patent Application Publication No. 2008-272393

The high-frequency treatment instrument for an endoscope described in Patent Document 1 includes a pair of high-frequency electrodes that open and close in a fan shape. Each high-frequency electrode has a convex electrode exposed surface elongated in the front-rear direction at the center portion in the width direction so that the pair of high-frequency electrodes face each other and close when the pair is in the closed state. Further, on both sides of the exposed electrode surface, a stepped portion is formed that is stepped with respect to the exposed electrode surface, and the portion outside the outer edge of the stepped portion is formed into a slope shape that gradually expands outward (paragraph number 0012,0013, Figures 1 and 2).

When in the closed state, the exposed surfaces of a pair of opposing electrodes sandwich living tissue between them, and the highest high-frequency current density generates the highest Joule heat, which cuts the living tissue and cuts the living tissue on both sides of the exposed electrode surfaces. At the stepped portion, the current density becomes sparse, causing the living tissue to become raw, resulting in a hemostatic effect, and a stable hemostatic state is maintained at the sloped portions on both sides of the stepped portion (Paragraph No. 0015).

However, according to the high-frequency treatment instrument for an endoscope described in Patent Document 1, when the pair of opposing electrode exposed surfaces is closed, the gap between the pair of electrode exposed surfaces is not maintained at a predetermined distance that allows bubbles to occur. Since the structure is such that the electrodes close continuously until they come into close contact, there is a risk of cutting the blood vessels when the exposed surfaces of the opposing pair of electrodes pinch the living tissue including the blood vessels and make an incision while stopping the bleeding. In addition, since there is not enough time for bubbles to generate between the exposed electrode surfaces and between the stepped portions, the high heat generated between the exposed electrode surfaces is actively heated to the stepped portions on both sides of the exposed electrode surfaces, and the stepped portions are further heated. It is not possible to actively heat the slopes on both sides of the tumor, it is difficult to appropriately suppress the temperature rise of normal living tissue after excision of a lesion, and there is no excellent operability when making an incision. There is a problem. Additionally, when performing other treatments, the endoscopic high-frequency treatment device must be removed from the endoscope and replaced with another treatment device, which can take time. .

The present invention has been made to solve the above-mentioned problems, and has a marking function, an incision function, a peeling function, and a closing hemostasis function by electrocautery as functions that can be applied to ESD procedures for living tissues in body cavities. An object of the present invention is to provide an electrocautery incision tool for an endoscope that has excellent operability.

In order to achieve the above object, the electrocautery dissection tool for an endoscope according to the present invention includes a flexible coil sheath that can be inserted into and removed from a channel of an endoscope, and a conductive sheath that is arranged to be movable in and out of the coil sheath. an operating section connected to each rear end side of the coil sheath and the operating wire to move the operating wire forward and backward; a cylindrical section provided at a distal end of the coil sheath; and a cylindrical section disposed at a distal end side of the cylindrical section. a distal treatment section support means having a pair of opposing arm portions extending from each other, and a pair of distal incision pieces molded from an electrically conductive material, the pair of distal distal cut pieces forming the distal treatment section support means of the pair of treatment section support means. a distal treatment section that is pivotally supported between the arms and opens and closes in conjunction with the advance and retreat of the operating wire to apply a required voltage to incise the affected part of the living tissue; The distal end portion of each piece is formed into a rod shape having an opposing surface portion, and each of the distal end portions has an outer protrusion for scratching and marking on the distal end portion of the outer surface opposite to the opposing surface portion. It is characterized by being

In addition to the configuration of the first aspect, the electrocautery incision tool for an endoscope according to a second aspect of the present invention has an inner protrusion on the tip of at least one of the opposing surfaces. In the closed state, the inner protrusion causes the opposing surface portions to approach each other with a gap between them.

In addition to the configuration of the first aspect, the electrocautery incision tool for an endoscope according to a third aspect of the present invention is configured such that the pair of distal incision pieces are in close contact with each other in a closed state. It is characterized by being

According to the present invention, the present invention has a marking function by electrocautery, a perforation function, an incision function, a peeling function, and a closing and hemostasis function as functions that can be applied to ESD procedures for living tissues in body cavities, and has excellent operability. A endoscopic electrocautery dissection tool can be provided.

1 is a diagram for explaining an endoscope system including an electrocautery incision tool for an endoscope according to Embodiment 1 of the present invention. 1 is an overall view of an electrocautery incision tool for an endoscope according to Embodiment 1 of the present invention. Regarding the electrocautery dissection tool for an endoscope according to Embodiment 1 of the present invention, FIG. 3(A) is a front view showing the distal end of the treatment section with the distal treatment section closed, and FIG. 3(B) is a front view of the distal end of the distal treatment section. FIG. 3(C) is a vertical sectional front view showing the distal end of the treatment section in a closed state, FIG. 3(D) is a longitudinal front view showing the distal end of the treatment section in an open state, and FIG. FIG. FIG. 7 is a front view showing the distal end of the electrocautery dissection tool for an endoscope according to Embodiment 2 of the present invention with the distal treatment section closed. FIGS. 5A to 5F are process diagrams of a series of ESD procedures performed using the endoscopic electrocautery dissection tool according to Embodiment 1 of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of an electrocautery incision tool for an endoscope according to the present invention will be described with reference to the drawings. In the following description, the side where the distal treatment section is located will be referred to as the distal end side, and the side where the operating section will be located will be referred to as the proximal end side.

[Embodiment 1]
[Endoscope system]
FIG. 1 shows an endoscope system 1 to which an electrocautery dissection tool for an endoscope according to a first embodiment is applied. The endoscope system 1 includes an insertion section 2 for insertion into a body cavity of a living body, and an endoscope operation section having a dial provided at the proximal end for bending the tip of the insertion section 2 in vertical and horizontal directions. 3, and a treatment instrument introduction section 4 arranged to connect between the insertion section 2 and the endoscope operation section 3, and a treatment instrument introduction section 4 arranged to connect between the insertion section 2 and the endoscope operation section 3. An endoscope channel 5 is formed, and a pair of distal incision pieces 15 are provided in the endoscope channel 5 as a distal treatment section for treating an affected part of a living body of an electrocautery incision tool 10 for an endoscope, which will be described later. 16 and the sheath 11 are inserted therethrough and operated by the operation section 13.

[Basic configuration of electrocautery cutting tool for endoscope]
FIG. 2 shows an electrocautery incision tool 10 for an endoscope according to the first embodiment. The electrocautery incision tool 10 for an endoscope is used to incise a living tissue in a body cavity while sandwiching it between a pair of distal cutting pieces 15 and 16 while applying a required current to electrocauterize the living tissue and stop bleeding.

The electrocautery dissection tool 10 for an endoscope includes an elongated flexible sheath 11 that can be inserted into and removed from an endoscope channel 5, an operating wire 12 that is arranged to be movable in and out of the sheath 11, and an operating wire 12. An operating section 13 for advancing and retracting, a distal treatment section support member 14 which is a treatment section support means fixedly connected to the distal end of the sheath 11, and a distal end rotatably supported by the distal treatment section support member 14 by a support shaft 18. A pair of distal incision pieces 15 and 16 are provided as a treatment section.

The sheath 11 is an elongated cylindrical body with a length of 1500 to 2000 mm, which is flexible and has appropriate stiffness (bending resistance). The sheath 11 of this embodiment includes a coil sheath 11a and a resin jacket 11b that covers the outer surface of the coil sheath 11a. The resin jacket 11b is made of PTFE, PEEK, PPS, polyethylene, polyimide, or the like, and has flexibility and electrical insulation properties. The coil sheath 11a is preferably a coil sheath formed by closely winding a metal material such as a stainless steel wire having a rectangular cross-sectional shape, for example.

In the electrocautery dissection tool 10 for an endoscope, an electrically insulating coating is formed on the inner surface of the coil sheath 11a and the outer surface of the distal treatment section support member 14. In a configuration in which the resin outer sheath 11b is not provided, an electrically insulating coating may be formed on the inner and outer surfaces of the coil sheath 11a.

The operating wire 12 is loosely arranged in the sheath 11 so as to be movable back and forth, and is made of a torque wire that is conductive and has a high rotation followability. For example, the entire length of the operating wire 12 may be made of stainless steel, or the proximal end portion made of stainless steel and the distal end portion made of Nitinol (nickel titanium alloy) may be connected with a stainless steel pipe. .

The operating section 13 includes an operating section main body 13a and a slider 13b. The operating section main body 13a has a distal end connected to the proximal end of the coil sheath 11a. The slider 13b is provided so as to fit and slide in the operating section main body 13a within a range corresponding to the slit provided on the side surface of the operating section main body 13a, and is introduced into the interior from the distal end surface of the operating section main body 13a. It is connected to the base end of the operating wire 12.

The operating section 13 can move the operating wire 12 relative to the coil sheath 11a by relatively sliding the operating section main body 13a and the slider 13b (advancing/retracting operation), and moves the slider 13b in the left direction (in the figure). By moving the operating wire 12 to the distal end side), the operating wire 12 can be moved distally relative to the coil sheath 11a to open the pair of distal incision pieces 15 and 16, and the slider 13b can be moved to the right in the figure (proximal end side). By moving the operating wire 12 toward the proximal end side relative to the coil sheath 11a, the pair of distal incision pieces 15 and 16 can be closed. Therefore, the operating section 13 can move the operating wire 12 forward and backward relative to the coil sheath 11a, and can also open and close the pair of distal incision pieces 15 and 16 through the advancing and retreating operation of the operating wire 12. It is configured.

As shown in FIG. 3A, the distal treatment section support member 14 includes a cylindrical portion 14a that is fitted and connected to the distal end of the coil sheath 11a, and a pair of opposing arm portions that extend toward the distal end from the cylindrical portion 14a. 14b. The pair of distal incision pieces 15 and 16 are supported by the distal treatment section support member 14 so as to be openable and closable. The pair of distal incision pieces 15, 16 has a shape that is divided into middle portions (crossing portions) 15a, 16a, proximal portions 15b, 16b, and distal portions 15c, 16c. The tip side portions 15c and 16c have a shape with an angular protrusion on the outside of the tip. When the distal end portions 15c and 16c are closed, they can be used as needle-like scalpels or markers, and when opened and closed, they can be used as scissors.

As shown in FIGS. 3(B), (C), and (D), the pair of distal incision pieces 15, 16 functionally includes distal portions 15c, 16c, middle portions 15a, 16a, and proximal portion 15b. , 16b.

Each middle portion (crossing portion) 15a, 16a of the pair of distal incision pieces 15, 16 has an axial hole, and the two axial holes are aligned to form the pair of arm portions 14b, 14b of the distal treatment section support member 14. The support shaft 18 is aligned uniaxially with a pair of bearing holes located between the tip portions and provided at the tip portions of the pair of arm portions 14b, 14b, and the support shaft 18 passes from one bearing hole to the other bearing hole. has been done.

The support shaft 18 is forcibly fitted into the bearing holes of the pair of arm parts 14b, 14b, or is fixed by laser welding after fitting, and the support shaft 18 is formed in the middle part (crossing) of the pair of tip cut pieces 15, 16. It is loosely fitted into the shaft holes of portions 15a and 16a. Therefore, in the pair of distal incision pieces 15 and 16, middle portions (intersecting portions) 15a and 16a are pivoted between the pair of arm portions 14b and 14b of the distal treatment section support member 14, and distal end portions 15c and 16c are Can be opened and closed.

The base end portions of the pair of distal end cut pieces 15, 16 are connected to the distal end portions of the pair of opening/closing links 19, 20 by pin shafts 22, 23, and each of the pair of opening/closing links 19, 20 The proximal end portion is connected to the distal end portion of the forward/backward transmission link 21 by a pin shaft 24, and the forward/backward transmission link 21 is connected to the operating wire 12.

Specifically, the pin shaft 22 is passed through the pin shaft hole provided in the proximal end portion 15b of one of the distal end cut pieces 15 and the pin shaft hole provided in the distal end of one of the opening/closing links 19, and the pin shaft 22 is stopped. By being attached, one tip cutting piece 15 and one opening/closing operation link 19 are connected. The pin shaft hole provided in the proximal end portion 16b of the other distal end cut piece 16 and the pin shaft hole provided in the distal end of the other opening/closing link 20 are overlapped, and the pin shaft hole is inserted into these pin shaft holes. 23 is passed through and fixed. Thereby, the other tip cutting piece 16 and the other opening/closing operation link 20 are connected. Therefore, the base end portions 15b, 16b of the distal end cutting pieces 15, 16 and the opening/closing operation links 19, 20 are linked in a diamond shape.

Furthermore, the pin shaft holes provided at the base ends of the pair of opening/closing links 19 and 20 are overlapped on both sides of the pin shaft holes provided at the tip end of the forward/backward transmission link 21, and the pin shaft holes are placed in these shaft holes. The pair of opening/closing links 19 and 20 and the opening/closing link 19 are connected by passing the shaft 24 through and fixing it.

The reciprocating power transmission link 21 has a rod-like outer shape and has a wire receiving hole axially inward from the base end surface. They are connected and fixed by screwing in screws, silver brazing, soldering, caulking, etc., thereby connecting the advancing/retracting power transmission link 21 and the operating wire 12.

Therefore, when the operating wire 12 is moved relative to the sheath 11 in the proximal direction, the crossing angle of the opening/closing links 19 and 20 becomes smaller, and the proximal portions 15b of the pair of distal incision pieces 15 and 16, 16b also becomes smaller, and as a result, the distal end portions 15c, 16c of the pair of distal incision pieces 15, 16 close (FIG. 3(B)), and the intersecting angle of the opening/closing links 19, 20 decreases. As becomes larger, the intersecting angle of the proximal portions 15b, 16b of the pair of distal incision pieces 15, 16 also becomes larger, and as a result, the distal portions 15c, 16c of the pair of distal incision pieces 15, 16 open in a fan shape. (Figure 3(A)). Thus, when the operating wire 12 is moved relative to the sheath 11, the distal end portions 15c, 16c of the pair of distal incision pieces 15, 16 open and close in a fan shape.

A pair of annular protruding seats 14c, 14c provided at the distal end of the opposing surface of each arm 14b so as to surround the support shaft 18 abuts on the middle portions 15a, 16a of the pair of distal cut pieces 15, 16. . This ensures that the pair of tip cutting pieces 15, 16 rotate smoothly without lateral vibration or lateral deviation.

Other basic configurations will be explained. The distal treatment section support member 14 and the pair of distal incision pieces 15 and 16 are made of stainless steel or nitinol (nickel titanium alloy), and the distal treatment section support member 14 and the resin jacket 11b of the sheath 11 have hydrophilic properties. A coating is formed so that the pair of distal incision pieces 15 and 16 to the sheath 11 can be smoothly introduced into the body cavity without strain.

The cylindrical portion 14a of the distal treatment section support means 14 and the distal end portion of the coil sheath 11a are connected by welding, brazing, or soldering. Alternatively, the outer shape of the distal end portion of the coil sheath 11a may be ground to provide a small diameter portion, and the cylindrical portion 14a may be fitted and fixedly connected to this small diameter portion.

Therefore, by moving the operation wire 12 forward and backward, the distal end portions 15c and 16c of the pair of distal incision pieces 15 and 16 can be opened and closed in a fan shape, and when closing, a high frequency current is applied to the inside of the body cavity. Treatments such as incision can be performed while electrocauterizing living tissue to stop bleeding.

[Characteristic configuration of electrocautery incision tool for endoscope]

The pair of tip cut pieces 15 and 16 are molded from a conductive material. Each of the distal end portions 15c and 16c is formed into a rod shape having a rectangular cross section perpendicular to the length direction and having opposing surface portions 15d and 16d. The pair of distal incision pieces 15 and 16 are supplied with electricity via the operating wire 12 and become electrode surfaces, and are exposed to living tissue not only on the opposing surface portions 15d and 16d but also on the entire length and circumferential surface of each distal portion 15c and 16c. Electrocautery is performed.

Each of the distal end portions 15c, 16c has outer protrusions 15e, 16e for scratching and marking purposes formed on the distal end portion of the outer surface on the opposite side to the opposing surface portions 15d, 16d. The outer protrusions 15e, 16e have the function of catching on the mucous membrane without slipping when the distal incision pieces 15, 16 are moved laterally in a closed state to perform incision treatment as a scalpel.

Further, each of the distal end portions 15c, 16c has inner protrusions 15f, 16f for maintaining the distance at the distal end portions of the opposing surface portions 15d, 16d. Each base end portion 15b, 16b is connected to the operating wire 12 via opening/closing links 19, 20 and a forward/backward transmission link 21.

The distal end portions 15c and 16c open and close in response to the forward and backward motion force of the operating wire 12, and are in a closed state when the operating wire 12 is in the most retracted state, and the opposing surface portions 15d and 16d are in a parallel state. and are maintained in close proximity.

When the distal end portions 15c and 16c are closed, the inner protrusions 15f and 16f are in contact with each other so that the gap c between the opposing surfaces 15d and 16d is maintained at a minute dimension of, for example, 0.2-1.0 mm. Close to each other.

The inner protrusions 15f, 16f may be provided not at the distal ends but at the proximal ends or midway parts of the opposing surface parts 15d, 16d. Further, it is sufficient that either one of the outer protrusions 15e and 16e is provided. Further, it is sufficient that either one of the inner protrusions 15f and 16f is provided.

When the inner protrusions 15f and 16f are provided at the tips of the facing surfaces 15d and 16d, in addition to the function of maintaining the gap interval, the inner protrusions 15f and 16f have the function of maintaining the gap when the pair of tip cut pieces 15 and 16 close from the fan-shaped open state. It also has a mucous membrane retaining function. The mucous membrane retaining function means that when the pair of distal incision pieces 15 and 16 are closed from the fan-shaped open state, the lesion located at the position sandwiched between the opposing surfaces 15d and 16d is removed from the opposing surfaces 15d and 16d. This function is to catch the mucous membrane of the lesion and hold it in place so that it does not escape in the distal direction between the facing surfaces 15d and 16d under pressure.

The inner protrusions 15f, 16f are arranged so that when the operating wire 12 is gently pulled toward the proximal end during the mucosal exfoliation process, the operating wire 12 becomes the most retracted state, and the distal end portions 15c, 16c close. 16f are in contact with each other, so that the opposing surface portions 15d and 16d are maintained in a substantially parallel and close state.

[Function of the tip treatment section consisting of the tip incision pieces 15 and 16]
Since the endoscope electrocautery incision tool 10 has the distal treatment section consisting of the pair of distal incision pieces 15 and 16 configured as described above, it has a marking function by electrocautery in the ESD procedure described in detail below. It has an incision function, a closing function to stop bleeding, and a function to avoid cutting blood vessels, and has excellent operability.

[Marking function]
The first step in the ESD procedure is to place an appropriate number of dot marks (marking marks) m around the lesion A (for example, 6 to 12). For this purpose, the insertion section 2 of the endoscope system 1 is inserted into the patient's body cavity, the position of the lesion A is confirmed by the endoscopic image, and the distal end of the sheath 11 inserted into the endoscope channel 5 is The distal treatment section (a pair of distal incision pieces 15, 16) is protruded from the distal end of the endoscope, and the outer protrusion 15e or 16e protruding by, for example, 0.5 mm is pressed against the mucous membrane around the lesion A, and the distal treatment section is inserted into the distal treatment section. Electrify high frequency current. As a result, the position where the outer protrusion 15e or 16e presses against the mucous membrane around the lesion A is slightly inserted, and since the outer protrusion 15e or 16e does not slip on the mucosal surface, it is electrocauterized at the targeted position and the marking mark m is created. It is formed. After that, the high frequency current is interrupted to separate the outer protrusion 15e or 16e from the mucous membrane, and the outer protrusion 15e or 16e is moved to the next pressing position on the mucous membrane around the lesion A to form a pressing marking mark m. This is repeated to form an appropriate number of dotted marking marks m in a circumferential arrangement, and the marking procedure is completed. After the marking procedure is completed, a liquid such as hyaluronic acid is then locally injected into the submucosal layer of the lesion, as shown in FIG. 5(B). Replace the endoscopic electrocautery incision tool 10 with an endoscopic injection tool G capable of supplying a liquid such as hyaluronic acid, and insert it toward the submucosal layer of the lesion A at a position outside the marking mark m. Injecting a drug solution can lift the mucous membrane of the affected area.

[Incision function]
After lifting the mucous membrane of the lesion A, as shown in FIG. 5(C), an annular recess R is incised in the mucous membrane at the outer periphery of the marking mark m. For this reason, the endoscopic electrocautery dissection tool 10 is replaced again, the outer protrusions 15e and/or 16e are pressed against the mucous membrane around the lesion A, and a high frequency current is applied to the distal treatment section, marking the marking mark m. go around the outer circumference of the As a result, the lateral protrusion 15e and/or 16e slightly inserts the pressed position of the mucous membrane around the lesion A, and since the lateral protrusion 15e or 16e does not slip on the mucosal surface, it is electrocauterized at the targeted position and the annular recess is formed. R can be incised.

[Peeling function]
After the annular recess R is incised, the lesion A is then peeled off little by little as shown in FIG. 5(D). For this purpose, the pair of distal incision pieces 15 and 16 of the endoscopic electrocautery incision tool 10 are closed, both of the outer protrusions 15e and 16e are aligned with the annular recess R, and a high-frequency current is directed toward the submucosa of the lesion A. Each time the electricity is applied and a certain size is punctured by electrocautery, the pair of distal incision pieces 15 and 16 are opened at a small angle, the incision width is increased, and then closed. The opening angle of the pair of distal incision pieces 15 and 16 is adjusted to the diameter, and by reaching the end on the other side of the annular recess R, the submucosal layer including the lesion A is peeled off. When opening the pair of distal incision pieces 15 and 16 at a small angle, the outer protrusions 15e and 16e catch the submucosal tissue, allowing for good incision.

The peeling function may be a method of giving a different action to the pair of tip cutting pieces 15, 16. The pair of distal incision pieces 15 and 16 are closed and the submucosal layer of the lesion A is pierced from one end of the annular recess R to the other diametrical end by electrocautery, and then the pair of distal incision pieces 15 and 16 are opened and kept open. The operation may be performed by pulling it to the insertion position, or by closing the pair of distal incision pieces 15 and 16, aligning the middle of one of the distal incision pieces with one end of the annular recess R, and cutting it open to the other end in the diametrical direction by electrocautery. It may be the case.

[Closing hemostasis function]
After the lesion A is removed, as shown in FIGS. 5E and 5F, the surface of the living body from which the lesion A has been removed is hemostasised. For this purpose, the pair of distal incision pieces 15 and 16 are opened into an appropriate fan shape and pressed against the surface of the living body so as to sandwich the lesion A, and while supplying high-frequency current and performing electrocautery, the operating wire 12 is inserted at the proximal end. When pulled slightly to the side, the operating wire 12 becomes the most retracted state, and the pair of distal incision pieces 15 and 16 are closed at a slow speed to sandwich the surface from which the lesion A has been removed, maintaining electrocautery for a predetermined number of seconds to stop bleeding. .

When the distance c between the opposing surfaces 15d and 16d is 0.2 to 1.0 mm, Joule heat is generated at high density between the opposing surfaces 15d and 16d, and the diseased tissue sandwiched between the opposing surfaces 15d and 16d is The mucous membrane turns into a large amount of bubbles due to the Joule heat, and these bubbles flow in the cutting direction so as to take away the heat between the opposing surfaces 15d and 16d, so that the opposing surfaces 15d and 16d are able to effectively dissipate heat. As a result, Joule heat is generated between the opposing surfaces 15d and 16d to which electricity is supplied, and the mucous membranes that swing to the opposing surfaces 15d and 16d generate and decompose a large amount of bubbles, causing the large amount of bubbles to flow in the resection direction along with heat. Therefore, when making a pinching incision, the incision can be made to safely separate the diseased area from healthy living tissue.

[Vessel cutting avoidance function]
In the above-mentioned closing hemostasis function, even when the pair of distal incision pieces 15 and 16 are in the closed state, the opposing surfaces 15d and 16d do not come into close contact with each other, and the gap c has a minute dimension of, for example, 0.2 to 1.0 mm. is retained. Therefore, even if a blood vessel is pinched during incision, there is no risk of crushing, occluding, or severing the blood vessel, and the bubbles move toward the resection along with heat, increasing the temperature of normal living tissue after the lesion is excised. This eliminates the risk of delayed perforation at the incision site, and provides excellent operability when making the incision.

[Embodiment 2]
As shown in FIG. 2, the endoscopic electrocautery dissection tool of this embodiment includes a sheath 11, an operating wire 12, an operating section 13, a distal treatment section support member 14, and a pair of components shown in FIG. In place of the distal end cutting pieces 15 and 16, a distal treatment section consisting of a pair of distal cutting pieces 15A and 16A shown in FIG. 4 is provided.

The distal treatment section consisting of a pair of distal incision pieces 15A, 16A is formed into a rod shape, with each distal side portion 15c, 16c having opposing surface portions 15d, 16d. Outer protrusions 15e and 16e for scratching and marking are formed at the tips of the outer surfaces on the opposite side, and in the closed state, the opposing surfaces 15d and 16d are in close contact with each other.

According to the distal treatment section of this embodiment, since the distal treatment section consisting of the pair of distal incision pieces 15 and 16 is configured as described above, it can be used in the ESD procedure described in detail below. Similarly, it is equipped with a marking function by electrocautery, an incision function, and a closing hemostasis function as functions that can perform multiple treatments on living tissues within body cavities. It is possible to provide an electrocautery dissection tool for an endoscope that is excellent in operability and can omit the trouble and time of inserting and removing and replacing.

On the other hand, according to the distal treatment section of this embodiment, in the closed state, the facing surfaces 15d and 16d are not in close proximity to each other, but in close contact with each other, so that the blood vessel cutting avoidance function is not affected. Not prepared.

According to the present invention, the distal incision tool consisting of a pair of distal incision pieces has a marking function by electrocautery, an incision function, a closing hemostasis function, and a blood vessel cutting function as functions that can be applied to ESD procedures for living tissues in body cavities. It is possible to provide an electrocautery incision tool for an endoscope that has the effect of having an avoidance function and is excellent in operability.

1...endoscope system,
2...insertion part,
3...endoscope operation section,
4...Treatment instrument introduction part,
5...endoscope channel,
10...Electrocautery incision tool for endoscope,
11...sheath,
11a...Coil sheath,
11b...Resin jacket,
12...operation wire,
13...operation unit,
13a...operation unit main body,
13b...Slider,
14...Distal treatment section support member,
14a...cylindrical part,
14b...arm part,
14c...annular protruding seat,
15, 16...Tip incision piece,
15a, 16a...middle part,
15b, 16b...base end portion,
15c, 16c...Tip side part,
15d, 16d...Opposing surface part,
15e, 16e...outer projections,
15f, 16f...inner protrusion,
18...Support shaft,
19, 20... link for opening/closing operation,
21...Advance/retreat transmission link,
22, 23, 24...Pin shaft c...Gap.

Claims (3)

a flexible coil sheath that can be inserted into and removed from a channel of an endoscope;
an electrically conductive operating wire arranged so as to be movable in and out of the coil sheath;
an operating section that is connected to each rear end side of the coil sheath and the operating wire and operates the operating wire to advance or retreat;
distal treatment section support means having a cylindrical portion provided at the distal end of the coil sheath and a pair of opposing arm portions extending from the cylindrical portion toward the distal end;
It has a pair of distal incision pieces molded from a conductive material, the pair of distal incision pieces are pivotally supported between the pair of arm parts of the treatment section support means, and are opened and closed in conjunction with the advancement and retreat of the operation wire. and a distal treatment section that applies a required voltage to incise the affected part of the biological tissue,
The distal treatment section is
The distal end portion of each of the distal incision pieces is formed into a rod shape having opposing surface portions,
An electrocautery dissection tool for an endoscope, wherein each of the distal end portions has an outer protrusion for scratching and marking on the distal end portion of the outer surface opposite to the opposing surface portion. The pair of distal end cut pieces include an inner protrusion at the distal end of at least one of the opposing surfaces, and in a closed state, the inner protrusions cause the opposing surfaces to approach each other with a gap. The endoscopic electrocautery incision tool according to claim 1, characterized in that: The electrocautery incision tool for an endoscope according to claim 1 , wherein the pair of distal incision pieces are configured such that the opposing surfaces are in close contact with each other in a closed state.

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