JP2015186534A - Hood for endoscope and endoscope treatment instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the mucous membrane from being hurt even when weak mucous membranes of the large intestine or the like are treated, to allow the mucous membrane to be reliably pealed off from the muscle layer, and to improve workability in a treatment instrument.SOLUTION: A hood 10 for an endoscope which is installed in an end part 20b of an endoscope 20 and used comprises a material having flexibility and elasticity. In a hood part 12, an end part 12s opposite to an endoscope installation part 11 has a part in its circumferential direction as an orthogonal surface 14 orthogonal to a central axis C of the hood part 12. In the hood part 12, the remaining part in the circumferential direction of the end part 12s is an inclined plane 15 inclined to the side of an endoscope installation part 11 from a position continuing circumferential direction both end parts 14a, 14a of the orthogonal surface 14 with respect to the central axis C of the hood part 12.

Description

  The present invention relates to an endoscope hood and an endoscope treatment tool.

In the lumen of the gastrointestinal tract, many mucosal resections have been performed to remove and remove mucosal tissues such as mucosal tumors from the muscular tissue that is the lower layer of the mucosa using a treatment tool such as a high-frequency knife under the endoscope. Yes. Among them, in endoscopic submucosal resection in which a wide range of mucosa is exfoliated and removed at once, it is necessary to prevent the mucosa exfoliated and separated during excision from covering the site where it is separated from the muscle layer.
In order to separate a wide range of mucous membranes, it is desirable to insert a high-frequency knife or the like at the boundary between the mucous membrane and the muscle layer while applying tension in the direction of peeling the separated mucosa from the muscle layer.

  In response to these requirements, Patent Document 1 discloses a configuration in which an endoscope hood is attached to the distal end of an endoscope. The endoscope hood is provided with a cylindrical protrusion at the endoscope tip, so that a predetermined distance is secured between the tip of the endoscope (objective lens) and the treatment site. Thereby, a treatment site can be observed favorably.

International Publication No. 2010/002570

Until now, endoscope hoods as described above have been used in treatment instruments mainly for the stomach and esophagus. However, when an endoscope hood as described above is attached to a treatment tool for treating the large intestine, the following problems exist.
First, the large intestine has a weaker mucosa than the stomach and esophagus. Since a conventional endoscope hood is formed of a hard resin such as polycarbonate, if it is used as it is for a large intestine having a weak mucous membrane, the mucosa of the large intestine may be damaged.

  Therefore, the endoscope hood can be formed of a softer material, but in that case, the rigidity of the endoscope hood may be insufficient when the mucosa cut off by the treatment instrument is peeled off from the muscle layer. is there. Then, the endoscope hood may be crushed or buckled, and the mucous membrane may not be reliably peeled off from the muscle layer.

  Furthermore, when a scissors that can be opened and closed are used as the treatment tool, it is difficult to secure a space for opening and closing the treatment tool and rotating it in the endoscope hood, which improves workability. There is room.

  The present invention has been made in view of the above circumstances, and even when a weak mucous membrane such as the large intestine is a treatment target, the mucosa is prevented from being damaged and the mucosa is surely peeled off from the muscle layer. It is another object of the present invention to provide an endoscope hood and an endoscope treatment tool that can improve the workability of the treatment tool.

The present invention employs the following means in order to solve the above problems.
That is, the present invention is an endoscope hood used by being attached to the distal end portion of an endoscope, which is formed on the proximal end side and into which the distal end portion of the endoscope is inserted. And a hood portion formed on the distal end side and having a cylindrical shape, and at least the hood portion is made of a material having flexibility and elasticity, and the endoscope mounting portion in the hood portion is The distal end portion on the opposite side has a part of the hood portion in the circumferential direction orthogonal to the central axis of the hood portion, and the remaining portion of the hood portion in the circumferential direction continues to the end of the orthogonal surface. And an inclined surface inclined with respect to the central axis of the hood portion from the position to the endoscope mounting portion side.

Since the hood part is made of a material having flexibility and elasticity, it can prevent the mucous membrane from being damaged by the hood part even when a soft large intestine or the like is compared with the stomach or esophagus. .
Moreover, since the inclined surface is formed in the front-end | tip part, this prevents a treatment tool from interfering with a hood part when opening / closing and rotating a treatment tool inside a hood part. be able to. In this way, the operating area of the treatment tool can be expanded in the hood portion.
Further, in the hood portion, the inclined surface is formed only in a part of the tip portion in the circumferential direction, and the other portions are orthogonal surfaces. Thereby, the operation area | region of the treatment tool in a hood part can be ensured compared with the case where the whole front-end | tip part of a hood part is made into an inclined surface. Thereby, it is possible to safely perform an operation in which the hood portion is inserted into the gap between the mucous membrane and the muscle layer and the incised mucosa is peeled off from the muscle layer.

The inclined surface has an inclination angle θ1 with respect to a cross section orthogonal to the central axis.
10 ° ≦ θ1 ≦ 40 °
You may make it form so that it may become.
If the inclination angle θ1 is smaller than 10 °, the dimension of the distal end portion of the hood portion on the inclined surface retracting from the orthogonal surface toward the endoscope mounting portion becomes small, and the effect of the inclined surface is reduced. On the other hand, if the inclination angle θ1 is larger than 40 °, the operating area of the treatment instrument cannot be secured.

The inner peripheral surface of the hood portion may have a tapered shape in which at least a part of the region where the inclined surface is formed has an inner diameter gradually expanding from the endoscope mounting portion side toward the distal end portion. .
Also by doing in this way, the operating area of the treatment instrument in the hood part can be expanded.

The hood portion has a tapered shape in which an outer diameter of at least a part of a region where the orthogonal surface is formed in the circumferential direction of the hood portion gradually increases in outer diameter from the distal end portion toward the endoscope mounting portion. You may make it be said.
This makes it easier for the hood portion to enter the gap between the mucous membrane and the muscular layer, and makes it easier to apply tension to peel the incised mucosa from the muscular layer.

  Endoscope having a tube-shaped observation optical system exposed at the distal end surface and a treatment tool protruding from the distal end surface, and an endoscope as described above attached to the distal end portion of the endoscope And a hood.

  According to the present invention, even when a weak mucous membrane such as the large intestine is a treatment target, the mucous membrane can be prevented from being damaged, and the mucosa can be surely peeled off from the muscle layer, and the workability in the treatment instrument can be improved. It becomes possible to improve.

It is a perspective view showing composition of an endoscope hood and an endoscope concerning this embodiment. It is a perspective view of an endoscope hood. It is sectional drawing along the central axis of the endoscope hood. It is a figure which shows an example of the state which has performed the treatment to the mucous membrane with the endoscope treatment tool which equipped the endoscope with the hood for endoscopes. It is a figure which shows an example of the treatment method in the state which mounted | wore the front-end | tip part of the endoscope with the hood for endoscopes.

Hereinafter, with reference to an accompanying drawing, a form for carrying out an endoscope hood and an endoscope treatment tool by the present invention is explained. However, the present invention is not limited only to these embodiments.
FIG. 1 is a perspective view showing configurations of an endoscope hood 10 and an endoscope 20 according to the present embodiment. FIG. 2 is a perspective view of the endoscope hood 10. FIG. 3 is a cross-sectional view of the endoscope hood 10 along the central axis C1. FIG. 4 is a diagram illustrating an example of a state in which treatment is performed on the mucous membrane 100 by the endoscope treatment tool A in which the endoscope hood 10 is attached to the endoscope 20.
As shown in FIG. 1, an endoscope hood 10 according to the present embodiment is used by being attached to a distal end portion 20 b of an endoscope 20. The endoscope treatment tool A is constituted by the endoscope 20 to which the endoscope hood 10 is attached.

  The endoscope 20 has a tubular endoscope body 21 made of an elastic material, a signal cable for the observation optical system 22, a light guide (not shown) for the illumination optical system 23, and an air / water supply tube 24. And the operation wire 25w of the treatment tool 25 is inserted.

  The observation optical system 22, the illumination optical system 23, and the nozzle 24 n of the air / water supply pipe 24 are exposed on the distal end surface 20 a of the endoscope 20. Further, a treatment instrument insertion hole 26 is formed in the distal end surface 20a of the endoscope 20, and the treatment instrument 25 provided at the distal end portion of the operation wire 25w protrudes from the distal end surface 20a through the treatment instrument insertion hole 26. .

  An operation unit (not shown) for operating the endoscope body 21 and the treatment instrument 25 is provided on the proximal end side (not shown) of the endoscope body 21 of the endoscope 20. By operating this operation unit, the endoscope main body 21 is bent and the direction of the distal end portion 21b can be changed. Further, by operating the operation unit, the treatment tool 25 can be operated via the operation wire 25w.

  The observation optical system 22 is for observing a treatment site or the like as a subject. In the observation optical system 22, subject light is converted into an electrical signal by a CCD (Charge Coupled Device) installed in the optical path of the subject light, and the converted electrical signal is transmitted via a signal cable and displayed as an image.

  The illumination optical system 23 irradiates illumination light in front of the distal end surface 20a of the endoscope 20 with light transmitted through a light guide (not shown).

  The air / water supply pipe 24 can eject a gas such as air or a liquid such as water from the nozzle 24n by an operation of the operation unit. By injecting gas or liquid from the air / water supply tube 24, dirt attached to the distal end surface 20a of the endoscope 20, the observation optical system 22, and the inner surface of the endoscope hood 10 can be removed.

  The treatment instrument 25 may be a high-frequency knife or the like, or may be a scissors-like openable / closable as shown in the present embodiment. By operating the treatment tool 25 with an operation unit (not shown), it is possible to treat a lesion to be treated. Further, by connecting a suction mechanism (not shown) to the treatment instrument insertion hole 26, the cleaning water, body fluid, and the like in the endoscope hood 10 can be sucked through the treatment instrument insertion hole 26.

  The configuration of the endoscope 20 described above is merely an example, and other configurations can be appropriately employed.

As shown in FIGS. 1 to 3, the endoscope hood 10 has a cylindrical shape in which a proximal end 10 a and a distal end 10 b are penetrated.
The endoscope hood 10 is formed on the proximal end 10a side, the endoscope mounting portion 11 into which the distal end portion 20b of the endoscope 20 is inserted, the hood portion 12 formed on the distal end 10b side, It has.
In the endoscope hood 10, at least the hood portion 12 is formed of a material having flexibility and elasticity. Such a material has, for example, a Shore A hardness k,
It is preferable to select such that 30 degrees ≦ k ≦ 60 degrees.
In the present embodiment, the entire endoscope hood 10 is formed of an elastic material such as rubber, polyvinyl chloride, or thermoplastic elastomer. Furthermore, it is desirable that the hood portion 12 has transparency. Therefore, a thermoplastic elastomer or the like is preferable as a material of the endoscope hood 10.

The endoscope mounting portion 11 is set so that its inner diameter fits with the outer peripheral surface of the distal end portion 20 b of the endoscope 20. The endoscope mounting portion 11 has the endoscope hood 10 attached to the distal end portion 20b of the endoscope 20 by fitting the distal end portion 20b of the endoscope 20 into the endoscope mounting portion 11. The
Here, the inner diameter of the hood portion 12 on the endoscope mounting portion 11 side is formed to be smaller than the inner diameter of the endoscope mounting portion 11, whereby a step portion 11 d is formed at the innermost portion of the endoscope mounting portion 11. Is formed. When the distal end portion 20b of the endoscope 20 abuts against the stepped portion 11d, the distal end portion 20b of the endoscope 20 is securely fitted into the endoscope mounting portion 11.
Furthermore, unevenness and the like that fit each other can be formed on the inner peripheral surface of the endoscope mounting portion 11 and the outer peripheral surface of the distal end portion 20b of the endoscope 20. Thereby, the endoscope hood 10 can be reliably fixed to the distal end portion 20 b of the endoscope 20.

The hood portion 12 projects forward from the distal end surface 20a of the endoscope 20 in a state where the endoscope mounting portion 11 is mounted on the distal end portion 20b of the endoscope 20, and surrounds the space in front of the distal end surface 20a. Is provided. As a result, the treatment tool 25 protruding from the distal end surface 20 a is positioned inside the hood portion 12.
As described above, the hood portion 12 is formed of a transparent material so that the lumen inner wall can be observed with the endoscope 20 through the hood portion 12 and through the hood portion 12 through the hood portion 12. it can.
At this time, an appropriate marking may be applied to the inner peripheral surface of the hood part 12 so that the direction of the rotation direction of the hood part 12 can be easily grasped when the observation optical system 22 performs observation.

  Further, it is preferable to perform hydrophilic treatment or water repellency treatment on at least the inner peripheral surface 12 a of the hood portion 12. Thereby, the water, body fluid, etc. which entered the inside of the hood part 12 are easily discharged from the front end side opening part 12b of the hood part 12 or a drain hole 13 which will be described later. As a result, the visual field of the endoscope 20 can be effectively secured. The method of hydrophilic treatment or water repellency treatment is not particularly limited. For example, in the case of hydrophilic treatment, film formation by a vapor phase method such as sputtering or vapor deposition, film formation by a liquid phase method such as dipping coating or spin coating. Further, there can be used a method such as film formation in which a chemical agent for forming a hydrophilic film is applied by cloth, absorbent cotton or the like, a plasma treatment method for surface hydroxylation, or the like.

  As shown in FIG. 2, in the hood part 12, it is preferable that at least one drain hole 13 is attached in the vicinity of the proximal end part on the endoscope mounting part 11 side. By providing the drain hole 13, water, body fluid, and the like that have entered the hood portion 12 can be discharged to the outside. Further, by setting the position of the drain hole 13 near the proximal end of the hood 12 on the endoscope mounting part 11 side, the drain hole 13 does not enter the field of view of the endoscope 20, and the treatment is performed. In addition, the visual field of the endoscope 20 can be kept good. Here, there is no intention to limit the shape and number of the drain holes 13.

Now, the food | hood part 12 of this embodiment has a front-end | tip shape as shown below.
That is, the distal end portion 12 s of the hood portion 12 on the side opposite to the endoscope mounting portion 11 has a part in the circumferential direction as an orthogonal surface 14 orthogonal to the central axis C of the hood portion 12. And in the hood part 12, the circumferential direction remainder of the front-end | tip part 12s is the circumferential direction both ends of the orthogonal surface 14 with respect to the surface orthogonal to the central axis C1 of the hood part 12 (namely, surface where the orthogonal surface 14 is located). The inclined surface 15 is inclined from the position continuous with 14a, 14a toward the endoscope mounting portion 11 side.
Here, as shown in FIG. 4, when the endoscope hood 10 performs a treatment on the mucous membrane 100 as a treatment target site, the orthogonal surface 14 is positioned on the mucosa 100 side, and the inclined surface 15 is a muscle. It is attached to the distal end portion 20b of the endoscope 20 so as to be positioned on the layer 101 side.

Here, as shown in FIG. 3, when the hood portion 12 is viewed from the side, the radial dimension Y of the region where the inclined surface 15 is formed with respect to the diameter X of the tip portion 12s of the hood portion 12 is:
(X / 6) ≦ Y ≦ (2X / 3)
It is preferable to set so that.

The inclined surface 15 has an inclination angle θ1 with respect to a cross section orthogonal to the central axis C1 (surface on which the orthogonal surface 14 is located), for example,
10 ° ≦ θ1 ≦ 40 °
It is preferable to form such that

In addition, the inclined surface 15 has a notch length (the stepped portion from the orthogonal surface 14 to the inclined surface 15 is the longest) with respect to the length L1 of the hood portion 12 (the length from the step portion 11d to the orthogonal surface 14) L1. 11d side position Ps) L2
1/6 ≦ L2 / L1 ≦ 2/3
You may form so that it may become.

Here, the length L1 of the hood portion 12 is preferably as short as possible. This is to prevent the hood portion 12 from being crushed or buckled when a tension for peeling the mucous membrane 100 from the muscle layer 101 is applied. For this reason, the length L1 of the hood part 12 is 2 ≦ L1 ≦ 8, for example.
Is preferable.

Further, the inclined surface 15 is arranged so that the endoscope hood 10 is attached to the distal end portion 20b of the endoscope 20 and the hood portion 12 at the position Ps of the inclined surface 15 from the central axis C2 of the treatment instrument insertion hole 26. The inclination angle θ2 to the edge 12e on the inner peripheral surface side is, for example,
5 ≦ θ2 ≦ 80
You may form so that it may become.

The hood portion 12 has a tapered shape in which an outer diameter of at least a part of a region where the orthogonal surface 14 is formed in the circumferential direction gradually increases from the distal end portion 12s toward the endoscope mounting portion 11. A tapered surface 16 is provided.
The inclination angle θ3 of the taper surface 16 with respect to the central axis C1 is, for example,
0 ° ≦ θ3 ≦ 30 °
It can be.
By adopting such a shape, the hood portion 12 can easily be inserted between the mucous membrane 100 and the muscle layer 101, and tension for peeling the incised mucosa 100 from the muscle layer 101 can be easily applied.

Further, the hood portion 12 is configured such that at least a part of the outer peripheral surface of the region where the inclined surface 15 is formed in the circumferential direction is a straight surface 17 parallel to the central axis C1.
Thereby, the submucosa 102 can be easily pressed down by the endoscope hood 10.

Further, the inner peripheral surface of the hood portion 12 is a taper in which the inner diameter from the central axis C1 gradually increases in at least a part of the region where the orthogonal surface 14 is formed from the endoscope mounting portion 11 side toward the distal end portion 12s. It can also be a surface 18.
The inclination angle θ4 of the tapered surface 18 with respect to the central axis C1 is, for example,
−10 ° ≦ θ4 ≦ 10 °
Is preferable.
In this way, at the minus side inclination angle θ4, the strength of the tip can be increased and deformation can be prevented. At the plus-side inclination angle θ4, the distal end side opening 12b is expanded, the observation visual field in the observation optical system 22 is expanded, and the visibility of the treatment target site is increased.

Further, the inner peripheral surface of the hood portion 12 is a taper in which the inner diameter from the central axis C1 gradually increases in at least a part of the region where the inclined surface 15 is formed from the endoscope mounting portion 11 side toward the distal end portion 12s. It can also be a surface 19.
The inclination angle θ5 of the taper surface 19 with respect to the central axis C1 is, for example,
5 ° ≦ θ5 ≦ 20 °
Is preferable.
By doing in this way, while the observation visual field in the observation optical system 22 spreads, the working area | region of the treatment tool 25 can be expanded.

Next, an example of a treatment method in a state where the endoscope hood 10 is attached to the distal end portion 20b of the endoscope 20 will be described with reference to FIG.
For this, first, the endoscope hood 10 is attached to the distal end portion 20 b of the endoscope 20. After the endoscope 20 is inserted orally, the treatment tool 25 is inserted into the treatment tool insertion hole 26 of the endoscope 20 and protrudes from the distal end surface 20a. In this state, circular markings 120 are made at substantially equal intervals around the entire periphery of the lesioned part 110 while applying a high-frequency current to the tip of a treatment instrument such as a needle scalpel. Next, the lesioned part 110 is bulged by local injection using physiological saline, sodium hyaluronate or the like. Thereafter, as shown in FIG. 5A, the scissors-like treatment tool 25 is inserted into the treatment tool insertion hole 26 of the endoscope 20 and protruded from the distal end surface 20a. In this state, by operating the treatment tool 25 with an operation unit (not shown), the lesioned part 110 is incised around the marking 120 along the periphery. At this time, since the field of view of the endoscope 20 is sufficiently secured by the hood unit 12, the peripheral incision can be surely performed while checking the state of the lesioned part 110.

After the peripheral incision of the lesioned part 110 is completed, the hood part 12 is inserted into the gap between the mucous membrane 100 and the muscle layer 101 as shown in FIG. 5B, and the submucosal layer 102 is peeled off by the treatment tool 25. At this time, since the field of view of the endoscope 20 is sufficiently secured by the hood portion 12, the submucosa 102 can be reliably peeled while confirming the state of the lesioned portion 110.
In addition, since the hood portion 12 is reduced in diameter toward the distal end by the tapered surface 16, the hood portion 12 can easily enter the gap between the mucous membrane 100 and the muscle layer 101, and the incised mucosa 100 is peeled off from the muscle layer 101. Therefore, it becomes easy to apply tension. Further, the submucosal layer 102 can be easily pressed by the straight surface 17 of the hood portion 12.

  It should be noted that at the time of the peripheral incision of the lesioned part 110 and the peeling of the submucosal layer 102, the washing water and body fluid that have entered the inner peripheral surface 12a of the hood part 12 are removed from the endoscope hood 10 through the drain hole 13. Can do.

Further, the water draining hole 13 also functions as an air intake when sucked through the treatment instrument insertion hole 26. For this reason, excessive suction is not applied when the lesioned part 110 is adsorbed to the distal end side opening 12b of the hood part 12, and the working space of the inner peripheral surface 12a of the hood part 12 by the suction of the lesioned part 110 is narrowed. However, it is possible to sufficiently absorb and drain water from the treatment instrument insertion hole 26 and secure the visual field of the endoscope 20.
Furthermore, if the inner peripheral surface 12a is subjected to hydrophilic treatment or water repellency treatment, washing water, body fluid, and the like can easily flow into the distal end side opening 12b and the drain hole 13, and treatment can be performed efficiently. At the same time, air can be taken from the drain hole 13. Thereby, in synergy with the effect of the hydrophilic treatment, water, body fluid, and the like can be discharged from the treatment instrument insertion hole 26, so that the visual field of the endoscope 20 can also be secured.

As described above, according to the endoscope hood 10 of the present embodiment, the hood portion 12 is formed of a material having flexibility and elasticity. Even in the case of treatment, the mucous membrane 100 can be prevented from being damaged by the hood portion 12.
Moreover, since the inclined surface 15 is formed in the front-end | tip part 12s, when the hood part 12 opens and closes the treatment tool 25 inside the hood part 12, or rotates, the treatment tool 25 is a hood part. 12 can be prevented from interfering. In this way, it is possible to expand the operating area of the treatment instrument 25 in the hood part 12, and workability is improved.

  In addition, at least a part of the region where the inclined surface 15 is formed on the inner peripheral surface of the hood portion 12 is a tapered surface 19. Also by doing in this way, the operation area of the treatment instrument 25 can be expanded.

  Furthermore, in the hood part 12, the inclined surface 15 is only formed in a part of the tip part 12s in the circumferential direction, and the other part is an orthogonal surface. Thereby, compared with the case where the whole front-end | tip part 12s of the hood part 12 is made into an inclined surface, the rigidity by the side of the orthogonal surface 14 of the hood part 12 increases. Thereby, when the hood part 12 is sunk into the gap between the mucous membrane 100 and the muscle layer 101 and the incised mucosa 100 is peeled off from the muscle layer 101, the hood part 12 is not easily buckled, and the required function is reliably performed. Can do.

  Thus, according to the endoscope hood 10 of the present embodiment, even when a weak mucous membrane 100 such as the large intestine is a treatment target, the mucous membrane 100 is prevented from being damaged, and the mucosa 100 is It can be surely peeled off from 101, and the workability of the treatment instrument 25 can be improved.

(Other embodiments)
The present invention is not limited to the above-described embodiments described with reference to the drawings, and various modifications are conceivable within the technical scope thereof.
For example, the configuration of the endoscope 20 is not limited at all. Moreover, the treatment tool 25 provided in the endoscope 20 is not limited to the scissors shape, and may be a scalpel or the like.
In addition to this, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 Endoscope hood 10a Base end 10b End 11 Endoscope mounting part 11d Step part 12 Hood part 12a Inner peripheral surface 12s End part 13 Drain hole 14 Orthogonal surface 14a, 14a Circumferential both ends 15 Inclined surface 16 Tapered surface 17 Straight surface 18 Tapered surface 19 Tapered surface 20 Endoscope 20a End surface 20b End portion 21 Endoscope body 21b End portion 22 Observation optical system 23 Illumination optical system 24 Air / water supply tube 24n Nozzle 25 Treatment tool 25w Operation wire 26 Treatment tool insertion hole 100 Mucosa 101 Muscle layer 102 Submucosa 110 Lesions

Claims (5)

An endoscope hood used by being attached to the distal end of an endoscope,
An endoscope mounting portion that is formed on the proximal end side and into which the distal end portion of the endoscope is inserted;
A hood portion formed on the tip side and having a cylindrical shape,
At least the hood part is made of a material having flexibility and elasticity,
In the hood portion, the distal end portion opposite to the endoscope mounting portion is such that a part of the hood portion in the circumferential direction is an orthogonal surface orthogonal to the central axis of the hood portion, and the hood portion in the circumferential direction The remaining portion includes an inclined surface inclined toward the endoscope mounting portion side from a position continuous with the end portion of the orthogonal surface with respect to the central axis of the hood portion. Endoscopic hood. The inclined surface has an inclination angle θ1 with respect to a cross section orthogonal to the central axis.
10 ° ≦ θ1 ≦ 40 °
The endoscope hood according to claim 1, wherein the endoscope hood is formed.   The inner peripheral surface of the hood portion has a tapered shape in which at least a part of the region where the inclined surface is formed has an inner diameter gradually expanding from the endoscope mounting portion side toward the distal end portion. The endoscope hood according to claim 1 or 2, characterized in that   The hood portion has a tapered shape in which an outer diameter of at least a part of a region where the orthogonal surface is formed in the circumferential direction of the hood portion gradually increases in outer diameter from the distal end portion toward the endoscope mounting portion. The hood for an endoscope according to any one of claims 1 to 3, wherein the hood is configured as described above. An endoscope having a tubular shape, an observation optical system exposed on the distal end surface, and a treatment tool protruding from the distal end surface;
An endoscope treatment tool comprising: the endoscope hood according to any one of claims 1 to 4, which is attached to a distal end portion of the endoscope.

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