JP2530068C

JP2530068C -

Info

Publication number: JP2530068C
Authority: JP
Publication date: 1999-02-10

Description

【発明の詳細な説明】【０００１】【産業上の利用分野】本発明は、内視鏡を利用して体腔内の病変組織を切除する際に用いられる把持
鉗子に関する。【０００２】【従来技術】内視鏡を利用した治療法の一つとして、ストリップバイオプシーと呼ばれる粘
膜切除術がある。このストリップバイオプシーは、粘膜の下組織層に内視鏡用注
射針にて生理食塩水を局所注入して平坦な病変組織を隆起させ、隆起した病変組
織を把持鉗子にて把持し、次いで高周波スネアにて病変組織を焼灼切除するもの
である。【０００３】このようなストリップバイオプシーの利点は、平坦な病変組織をその周辺の正
常組織を含めた形態できれいに切除できることにあり、内視鏡による早期癌の治
療を可能にするものとして、近年急速に普及しつつあり、また期待も大きい。【０００４】ところで、ストリップバイオプシーに用いられる把持鉗子としては、可撓性を
有するシースの先端に一対の鉗子部材を開閉可能に設けたものが従来より知られている（実公昭６３−１５１１１１号公報参照）。【０００５】【発明が解決しようとする課題】しかしながら、上述した従来の把持鉗子は、鉗子部材の開き角度が最大で９０
度程度であることから、鉗子部材の先端が粘膜に当たりづらく、比較的裂けに強
い粘膜筋板までも含めて粘膜を確実に把持することが困難であった。このため、
従来の把持鉗子では粘膜の上皮のみを把持してしまい、鉗子部材に把持された粘
膜を持ち上げて高周波スネアにて焼灼切除する際に粘膜が引き裂かれて把持鉗子
から外れてしまうことがあった。【０００６】特にストリップバイオプシーは癌組織を対象とするため、癌組織を確実に切除
することが重要であり、そのためには把持鉗子で十分に粘膜を持ち上げられるこ
とと、粘膜を確実に把持できることが要求される。また、生体組織を把持しても組織を座滅しないように把持することも要求され
る。【０００７】本発明は上記のような点に鑑みてなされたものであり、その目的は粘膜等の生
体組織を座滅させることなく確実に把持することができ、ストリップバイオプシ
ーに好適な把持鉗子を提供することにある。【０００８】【課題を解決するための手段及び作用】上記課題を解決するために本発明は、内視鏡の処置具挿通チャンネルを通して
体腔内に挿入されるシースと、このシースの先端部に開閉自在に設けられ前記体
腔内の組織を把持する爪部及び鰐歯を有する一対の鉗子部材と、前記一対の鉗子
部材が閉じたとき互いに対向する前記鰐歯間で形成される組織の座滅防止空間部
と、前記鉗子部材の後端部に回動自在に連結された一対のリンク部材と、前記シ
ースの後端部に設けられ前記リンク部材を介して前記鉗子部材を開閉操作する操
作部とを具備し、前記鉗子部材は少なくとも１２０度の開き角度を有するもので
ある。したがって、本発明では鉗子部材の先端が粘膜等の生体組織に垂直に近い状態
で当たることになるので、粘膜等の生体組織を確実に把持することができる。そ
して、生体組織は鰐歯間で形成された座滅防止空間部で把持されるので、組織は
座滅することなく把持される。【０００９】【実施例】以下、本発明の第１実施例を図１〜図７を参照して説明する。【００１０】図１は本発明の第１実施例に係る把持鉗子を示す図であり、この把持鉗子は同
図に示すように、可撓性を有するコイルシース１と、このコイルシース１の先端
に設けられた把持部２およびコイルシース１の後端に設けられた操作部３とから
構成されている。【００１１】前記把持部２は生体組織を把持するものであり、一対の鉗子部材４ａ，４ｂを
備えている。これらの鉗子部材４ａ，４ｂはコイルシース１の先端に固定された
保持部材６に軸５を介して回動自在に保持されており、先端側が開閉するように
なっている。また、鉗子部材４ａ，４ｂは図２に示すように先端に爪部７ａ，７
ｂを有しており、これらの爪部７ａ，７ｂで生体組織を把持するように構成され
ている。なお、鉗子部材４ａの先端に設けられた爪部７ａは鉗子部材４ａの先端
側から見ると凹形をなしており、鉗子部材４ｂの先端に設けられた爪部７ｂは鉗
子部材４ｂの先端側から見ると凸形をなしている。【００１２】また、前記鉗子部材４ａ，４ｂは図２に示すように互いに対向する面(把持面)
に鰐歯８ａ，８ｂを有しており、これらの鰐歯８ａ，８ｂおよび前記爪部７ａ，
７ｂで生体組織を把持するように構成されている。【００１３】なお、爪部７ａ，７ｂおよび鰐歯８ａ，８ｂは鉗子部材４ａ，４ｂが閉じてい
るときには図１に示すように互いに噛み合うようになっている。また、鉗子部材
４ａ，４ｂの側面は図４に示すように平面となっており、鰐歯８ａ，８ｂの谷部の稜線は鉗子部材４ａ，４ｂの側面内に限局されている(図３参照)。また、鉗子
部材４ａ，４ｂはその開き角度θが少なくとも１２０度以上となっている(図３
参照)。【００１４】前記保持部材６は先端部にスリット９（図２参照）を有しており、このスリッ
ト９内に鉗子部材４ａ，４ｂが開閉自在に保持されている。また、保持部材６は
コイルシース１内に連通する連通孔１０を有している。この連通孔１０内には連
結部材１１が摺動自在に保持されており、連結部材１１の先端部には連結ピン１
２を介してリンク部材１３ａ，１３ｂの後端部が回動自在に連結されている。そ
して、前記リンク部材１３ａ，１３ｂの先端部には連結ピン１４ａ，１４ｂを介
して鉗子部材４ａ，４ｂの後端部が回動自在に連結されている。【００１５】一方、前記連結部材１１の後端部には操作ワイヤ１５の一端が接続されている
。この操作ワイヤ１５の他端はコイルシース１内を挿通して操作部３のスライダ
１６に接続されており、このスライダ１６を操作して操作ワイヤ１５を前進させ
ると鉗子部材４ａ，４ｂが開くようになっている。【００１６】前記スライダ１６は操作部本体１７の後端に突設されたスライドガイド１８に
摺動自在に保持されており、スライドガイド１８の後端には指掛け部１９が設け
られている。【００１７】なお、前記操作部本体１７の先端には、コイルシース１の折れ曲がりを防止す
る折れ止めチューブ２０が突設されている。また、前記コイルシース１は表面を
電気絶縁性のチューブ２１で被覆され、コイルシース１の後端は操作部本体１７
内に設けられた管状部材２２および連結コイル２３を介して操作部本体１７に固
定されている。【００１８】なお、前記管状部材２２の後端部には、操作ワイヤ１５をスライダ１６に導く
案内管２４の先端部がねじ込まれている。また、管状部材２２にはチューブ２１の後端が突き当たる突き当て部２５が設けられているとともに、両側が平坦
な断面形状（図５参照）の傘部２６が設けられている。【００１９】上記のように構成される把持鉗子を用いて体腔内の病変組織を切除する場合に
は、まず図６に示すように病変部３１の真下にある粘膜下組織層３２に内視鏡用
注射針にて生理食塩水３３を局所注入し、粘膜３４と固有筋層３５とを粘膜下組
織層３２を境に分離させる。【００２０】次に、図示しない内視鏡の処置具挿通用チャンネルを通して把持鉗子を体腔内
に導入し、内視鏡のチャンネル口から把持鉗子の把持部２を突出させる。そして
、操作部３のスライダ１６を操作して鉗子部材４ａ，４ｂを開かせた後、鉗子部
材４ａ，４ｂの先端に設けられた爪部７ａ，７ｂを粘膜３４の表面に押し当てる
(図６参照)。【００２１】次に、この状態でスライダ１６を操作して操作ワイヤ１５を牽引すると、図７
に示すように鉗子部材４ａ，４ｂが閉じ、病変部３１を含む粘膜３４が把持鉗子
に把持される。【００２２】その後、図１４に示す如く内視鏡３６の他方のチャンネルから導入された高周
波スネア３７を把持鉗子に把持された粘膜３４にかけ、高周波スネア３７に高周
波電流を通電して把持鉗子に把持された粘膜３４を病変部３１と共に切除する。
なお、切除後は切除された粘膜３４を把持した状態で把持鉗子を内視鏡と共に体
腔外へ取り出す。【００２３】このように本実施例では、鉗子部材４ａ，４ｂの開き角度θが１２０度以上と
なっているので、図６に示すように鉗子部材４ａ，４ｂの先端に設けられた爪部
７ａ，７ｂが粘膜３４に対しほぼ垂直に近い状態で突き当たり、粘膜深部の粘膜
筋板３４ａまでも容易に把持することができる。また、鉗子部材４ａ，４ｂには
爪部７ａ，７ｂおよび鰐歯８ａ，８ｂが設けられ、これらの両方で粘膜等の生体組織を把持するので、大きな把持力で得られ、粘膜を引き上げる際にも病変部３
１を含む粘膜３４が鉗子部材４ａ，４ｂから外れることもない。【００２４】次に図８は本発明の第２実施例を示す図であり、この第２実施例が第１実施例
と異なる点は、鰐歯８ａ，８ｂの高さを低くした点である。なお、それ以外の構
成は第１実施例と同様である。【００２５】上記のような構成によると、鉗子部材４ａ，４ｂを閉じたときに鰐歯８ａ，８
ｂの間に空間部が形成されるので、生体組織を把持したときに組織が鰐歯８ａ，
８ｂによって座滅するのを防止できるとともに、爪部７ａ，７ｂの突出長が長く
なるので組織をより深く把持することができる。なお、上述した第１及び第２実
施例では、鉗子部材４ｂの先端に設けられた爪部７ｂを凸形としたが、図９に示
すように爪部７ａと同様に凹形としてもよい。上記のような構成によると、組織
を把持する際に爪部７ａ，７ｂがずれるようなことがなく、病変部を含む生体組
織をより確実に把持することができる。【００２６】次に本発明の第４実施例を図１０乃至図１３に示す。図１０及び図１１におい
て、４１は可撓性を有するコイル部材であり、このコイル部材４１の先端には把
持部４２が設けられている。この把持部４２は粘膜等の生体組織を把持するもの
であり、鉗子部材４３ａ，４３ｂ，４３ｃを備えている。これらの鉗子部材４３
ａ，４３ｂ，４３ｃはコイル部材４１の先端に固定された保持部材４４にピン４
５を介して回動自在に取り付けられており、保持部材４４に対し起倒可能となっ
ている。【００２７】前記鉗子部材４３ａ，４３ｂ，４３ｃは先端に爪部４６ａ，４６ｂ，４６ｃを
有している。また、鉗子部材４３ａ，４３ｂ，４３ｃは鰐歯４７ａ，４７ｂ，４
７ｃを有しており、これらの鰐歯４７ａ，４７ｂ，４７ｃおよび爪部４６ａ，４
６ｂ，４６ｃで生体組織を把持するように構成されている。【００２８】また、前記鉗子部材４３ａ，４３ｂ，４３ｃの端部には、操作ワイヤ４８ａ，
４８ｂの一端が連結されている。これらの操作ワイヤ４８ａ，４８ｂの他端はコ
イル部材４１の後端部に設けられた操作部（図示せず）のスライダに連結されて
おり、スライダにより操作ワイヤ４８ａ，４８ｂを牽引すると鉗子部材４３ａ，
４３ｂ，４３ｃが図１２に示す如く保持部材４４及びコイル部材４１に対してほ
ぼ垂直に起き上がり、爪部４６ａ，４６ｂ，４６ｃ及び鰐歯４７ａ，４７ｂ，４
７ｃが噛み合うようになっている。なお、コイル部材４１は可撓性を有するカバ
ーチューブ４９内に進退自在に挿通されている。【００２９】上記のような構成によると、鉗子部材４３ａ，４３ｂ，４３ｃの開閉方向がコ
イル部材４１の軸方向に対し垂直方向となるため、図１３に示すように内視鏡の
アプローチが生体組織に対し接線方向となるような部位(例えば大腸の管腔壁等)
でも容易に把持することが可能となる。【００３０】【発明の効果】以上説明したように本発明は、鉗子部材の開き角度を少なくとも１２０度以上
とすると共に、一対の鉗子部材が閉じたとき互いに対向する鰐歯間で形成される
組織の座滅防止空間部を設けたので、粘膜等の生体組織を座滅させることなく確
実に把持することができ、ストリップバイオプシーに好適な把持鉗子を提供でき
る。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grasping forceps used for excising a diseased tissue in a body cavity using an endoscope. [0002] One of the treatments using an endoscope is a mucosal resection called a strip biopsy. In this strip biopsy, physiological saline is locally injected into the lower tissue layer of the mucosa with an endoscope injection needle to raise flat diseased tissue, and the raised diseased tissue is gripped with gripping forceps, followed by a high-frequency snare. Is to cauterize and resect the diseased tissue. [0003] The advantage of such strip biopsy is that flat diseased tissue can be neatly resected in a form including normal tissue surrounding the diseased tissue. It is becoming popular, and expectations are high. Meanwhile, as a grasping forceps used in a strip biopsy, a grasping forceps provided with a pair of forceps members at the tip of a flexible sheath so as to be openable and closable has been conventionally known (Japanese Utility Model Publication No. 63-151111). reference). [0005] However, in the conventional gripping forceps described above, the opening angle of the forceps member is at most 90.
Because of the degree, the tip of the forceps member is hard to hit the mucous membrane, and it has been difficult to reliably grasp the mucous membrane including the mucosal muscle plate, which is relatively resistant to tearing. For this reason,
With the conventional grasping forceps, only the epithelium of the mucous membrane is grasped, and when the mucous membrane grasped by the forceps member is lifted and cauterized by a high-frequency snare, the mucous membrane may be torn and detached from the grasping forceps. In particular, since strip biopsy is intended for cancerous tissue, it is important to reliably remove the cancerous tissue. For this purpose, it is necessary that the mucous membrane can be sufficiently lifted by grasping forceps and that the mucous membrane can be securely grasped. Required. In addition, it is also required to hold the living tissue so that the tissue does not collapse.
You. [0007] The present invention has been made in view of the above points, and an object of the present invention is to provide a grasping forceps that can securely grasp a living tissue such as a mucous membrane without losing it , and is suitable for a strip biopsy. To provide. [0008] In order to solve the above problems, the present invention provides a sheath inserted into a body cavity through a treatment instrument insertion channel of an endoscope, and a distal end portion of the sheath. A pair of forceps members freely provided and having a claw portion and a crocodile for grasping tissue in the body cavity, and the pair of forceps
Tissue blanking prevention space formed between the crocodile teeth facing each other when the member is closed
When a pair of link members which are rotatably connected to the rear end portion of the forceps member and an operation portion for opening and closing the forceps member through the link member provided at the rear end of the sheath comprises The forceps member has an opening angle of at least 120 degrees. Therefore, in the present invention, the distal end of the forceps member comes into contact with the living tissue such as the mucous membrane in a state almost perpendicular to the living tissue, so that the living tissue such as the mucous membrane can be reliably grasped. So
Then, the living tissue is gripped by the anti-collapse space formed between the crocodile teeth.
It is gripped without losing. Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a view showing a grasping forceps according to a first embodiment of the present invention. As shown in FIG. 1, the grasping forceps is provided at a tip end of the coil sheath 1 having flexibility. And an operation unit 3 provided at the rear end of the coil sheath 1. The gripper 2 grips a living tissue and includes a pair of forceps members 4a and 4b. These forceps members 4a and 4b are rotatably held via a shaft 5 by a holding member 6 fixed to the distal end of the coil sheath 1, and the distal end side is opened and closed. Further, as shown in FIG. 2, the forceps members 4a, 4b have claw portions 7a, 7
b, so that the living tissue is gripped by the claws 7a and 7b. The claw portion 7a provided at the tip of the forceps member 4a has a concave shape when viewed from the tip side of the forceps member 4a, and the claw portion 7b provided at the tip of the forceps member 4b is provided at the tip side of the forceps member 4b. When viewed from above, it has a convex shape. As shown in FIG. 2, the forceps members 4 a and 4 b are opposed to each other (grip surfaces).
Have crocodile teeth 8a, 8b, and these crocodile teeth 8a, 8b and the claw portions 7a,
It is configured to hold a living tissue at 7b. When the forceps members 4a and 4b are closed, the claws 7a and 7b and the crocodile teeth 8a and 8b are engaged with each other as shown in FIG. The side surfaces of the forceps members 4a and 4b are flat as shown in FIG. 4, and the ridges of the valleys of the crocodile teeth 8a and 8b are limited to the side surfaces of the forceps members 4a and 4b (see FIG. 3). ). The forceps members 4a and 4b have an opening angle θ of at least 120 degrees (FIG. 3).
reference). The holding member 6 has a slit 9 at its tip (see FIG. 2), and forceps members 4 a and 4 b are held in the slit 9 so as to be openable and closable. Further, the holding member 6 has a communication hole 10 communicating with the inside of the coil sheath 1. A connecting member 11 is slidably held in the communication hole 10, and a connecting pin 1
The rear ends of the link members 13a and 13b are rotatably connected to each other through the second member 2. The rear ends of the forceps members 4a, 4b are rotatably connected to the distal ends of the link members 13a, 13b via connecting pins 14a, 14b. On the other hand, one end of an operation wire 15 is connected to a rear end of the connecting member 11. The other end of the operation wire 15 is connected to the slider 16 of the operation section 3 through the inside of the coil sheath 1. When the slider 16 is operated to advance the operation wire 15, the forceps members 4 a and 4 b are opened. Has become. The slider 16 is slidably held by a slide guide 18 protruding from the rear end of the operation section main body 17, and a finger hook 19 is provided at the rear end of the slide guide 18. At the end of the operation section main body 17, a buckling prevention tube 20 for preventing the coil sheath 1 from bending is protruded. The surface of the coil sheath 1 is covered with an electrically insulating tube 21, and the rear end of the coil sheath 1 is
It is fixed to the operation section main body 17 via a tubular member 22 and a connection coil 23 provided therein. A distal end of a guide tube 24 for guiding the operation wire 15 to the slider 16 is screwed into a rear end of the tubular member 22. The tubular member 22 is provided with an abutting portion 25 against which the rear end of the tube 21 abuts, and an umbrella portion 26 having a flat cross section on both sides (see FIG. 5). When excision of a diseased tissue in a body cavity using the grasping forceps configured as described above, first, as shown in FIG. 6, an endoscope is placed on a submucosal tissue layer 32 immediately below the lesioned part 31. A physiological saline solution 33 is locally injected with an injection needle, and the mucous membrane 34 and the proper muscle layer 35 are separated at the submucosal tissue layer 32. Next, the grasping forceps is introduced into the body cavity through the treatment tool insertion channel of the endoscope (not shown), and the grasping portion 2 of the grasping forceps is projected from the channel opening of the endoscope. Then, after operating the slider 16 of the operation unit 3 to open the forceps members 4a and 4b, the claws 7a and 7b provided at the tips of the forceps members 4a and 4b are pressed against the surface of the mucous membrane 34.
(See FIG. 6). Next, when the operation wire 15 is pulled by operating the slider 16 in this state, FIG.
As shown in (2), the forceps members 4a and 4b are closed, and the mucous membrane 34 including the lesion 31 is grasped by the grasping forceps. Thereafter, as shown in FIG. 14, a high-frequency snare 37 introduced from the other channel of the endoscope 36 is applied to the mucous membrane 34 gripped by the gripping forceps, and a high-frequency current is supplied to the high-frequency snare 37 to be gripped by the gripping forceps. The mucous membrane 34 thus removed is removed together with the lesion 31.
After the resection, the grasping forceps is taken out of the body cavity together with the endoscope in a state where the resected mucous membrane 34 is grasped. As described above, in the present embodiment, since the opening angle θ of the forceps members 4a, 4b is 120 degrees or more, the claw portions 7a provided at the tips of the forceps members 4a, 4b as shown in FIG. , 7b abut the mucous membrane 34 in a state almost perpendicular to the mucous membrane 34, so that the mucosal muscle plate 34a deep in the mucous membrane can be easily grasped. Further, the forceps members 4a, 4b are provided with claws 7a, 7b and crocodile teeth 8a, 8b, both of which grip biological tissues such as mucous membranes. Also lesion 3
The mucous membrane 34 including 1 does not come off from the forceps members 4a, 4b. FIG. 8 is a view showing a second embodiment of the present invention. The second embodiment differs from the first embodiment in that the heights of the crocodile teeth 8a and 8b are reduced. . The other configuration is the same as that of the first embodiment. According to the above configuration, the crocodile teeth 8a, 8b are closed when the forceps members 4a, 4b are closed.
b, a space is formed between the crocodile teeth 8a,
8b can be prevented from losing, and the protruding length of the claws 7a and 7b can be increased, so that the tissue can be gripped more deeply. In the first and second embodiments described above, the claw 7b provided at the tip of the forceps member 4b has a convex shape. However, as shown in FIG. 9, the claw 7b may have a concave shape like the claw 7a. According to the above configuration, the nails 7a and 7b do not shift when gripping the tissue, and the living tissue including the lesion can be gripped more reliably. Next, a fourth embodiment of the present invention is shown in FIGS. 10 and 11, reference numeral 41 denotes a coil member having flexibility, and a grip portion 42 is provided at an end of the coil member 41. The gripper 42 grips a living tissue such as a mucous membrane, and includes forceps members 43a, 43b, and 43c. These forceps members 43
a, 43b, and 43c are pins 4 attached to a holding member 44 fixed to the tip of the coil member 41.
5 so as to be rotatable, and can be turned upside down with respect to the holding member 44. The forceps members 43a, 43b, 43c have claw portions 46a, 46b, 46c at the tips. Further, the forceps members 43a, 43b, 43c are alligators 47a, 47b, 4
7c, and the crocodile teeth 47a, 47b, 47c and the claw portions 46a, 4
6b and 46c are configured to hold a living tissue. An operation wire 48a, an end of each of the forceps members 43a, 43b, 43c
One end of 48b is connected. The other ends of the operation wires 48a and 48b are connected to a slider of an operation unit (not shown) provided at the rear end of the coil member 41. When the operation wires 48a and 48b are pulled by the slider, the forceps member 43a is pulled. ,
12, 43b and 43c rise substantially perpendicularly to the holding member 44 and the coil member 41 as shown in FIG. 12, and the claw portions 46a, 46b, 46c and the crocodile teeth 47a, 47b, 4
7c mesh with each other. The coil member 41 is inserted into the cover tube 49 having flexibility so as to be able to advance and retreat. According to the above configuration, the opening and closing directions of the forceps members 43a, 43b, and 43c are perpendicular to the axial direction of the coil member 41. Therefore, as shown in FIG. Site that is tangential to (for example, the lumen wall of the large intestine)
However, it can be easily gripped. As described above, in the present invention, the opening angle of the forceps member is at least 120 degrees or more.
And formed between the crocodile teeth facing each other when the pair of forceps members are closed.
Since the tissue indentation prevention space portion is provided, living tissue such as mucous membranes can be reliably grasped without being destroyed, and a grasping forceps suitable for strip biopsy can be provided.

【図面の簡単な説明】【図１】本発明の第１実施例に係る把持鉗子の構成図。【図２】同実施例に係る把持鉗子の先端部分を示す斜視図。【図３】同実施例に係る把持鉗子の先端部分を示す側面図。【図４】図３の線Ｂ−Ｂに沿った断面図。【図５】図１の線Ａ−Ａに沿った断面図。【図６】第１実施例に係る把持鉗子の鉗子部材を粘膜組織に突き当てた状態
を示す図。【図７】同実施例に係る把持鉗子で粘膜組織を把持した状態を示す図。【図８】本発明の第２実施例に係る把持鉗子の先端部分を示す側面図。【図９】本発明の第３実施例に係る把持鉗子の先端部分を示す斜視図。【図１０】本発明の第４実施例に係る把持鉗子の先端部分を示す斜視図。【図１１】同実施例に係る把持鉗子の先端部分を示す側面図。【図１２】同実施例に係る把持鉗子の鉗子部材が閉じた状態を示す図。【図１３】同実施例の作用説明図。【図１４】把持鉗子に把持された粘膜組織に高周波スネアをかけた状態を示
す図。【符号の説明】１コイルシース２把持部３操作部４ａ，４ｂ鉗子部材７ａ，７ｂ爪部８ａ，８ｂ鰐歯１３ａ，１３ｂリンク部材１５操作ワイヤ１６スライダ３１病変部３２粘膜下組織層３４粘膜３５固有筋層４１コイル部材４３ａ〜４３ｃ鉗子部材４６ａ〜４６ｃ爪部４７ａ〜４７ｃ鰐歯４８ａ〜４８ｃ操作ワイヤBRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of a grasping forceps according to a first embodiment of the present invention. FIG. 2 is a perspective view showing a distal end portion of the grasping forceps according to the embodiment. FIG. 3 is a side view showing a distal end portion of the grasping forceps according to the embodiment. FIG. 4 is a sectional view taken along line BB in FIG. 3; FIG. 5 is a sectional view taken along line AA of FIG. 1; FIG. 6 is a view showing a state in which a forceps member of the grasping forceps according to the first embodiment is abutted against mucosal tissue. FIG. 7 is a diagram showing a state where the mucous membrane tissue is gripped by the gripping forceps according to the embodiment. FIG. 8 is a side view showing a distal end portion of a grasping forceps according to a second embodiment of the present invention. FIG. 9 is a perspective view showing a distal end portion of a grasping forceps according to a third embodiment of the present invention. FIG. 10 is a perspective view showing a distal end portion of a grasping forceps according to a fourth embodiment of the present invention. FIG. 11 is a side view showing the distal end portion of the grasping forceps according to the embodiment. FIG. 12 is a diagram showing a state in which the forceps member of the grasping forceps according to the embodiment is closed. FIG. 13 is an operation explanatory view of the embodiment. FIG. 14 is a diagram showing a state in which a high-frequency snare is applied to a mucous membrane tissue gripped by gripping forceps. DESCRIPTION OF SYMBOLS 1 Coil sheath 2 Gripping part 3 Operating part 4a, 4b Forceps members 7a, 7b Claw parts 8a, 8b Crocodile teeth 13a, 13b Link member 15 Operation wire 16 Slider 31 Lesions 32 Submucosal tissue layer 34 Mucosa 35 Specific Muscle layer 41 Coil members 43a to 43c Forceps members 46a to 46c Claw portions 47a to 47c Crocodile teeth 48a to 48c Operation wires

Claims

Claims: 1. A sheath inserted into a body cavity through a treatment instrument insertion channel of an endoscope, and a claw portion provided at a distal end portion of the sheath so as to be openable and closable to grip a tissue in the body cavity. And a pair of forceps members having crocodile teeth, and each other when the pair of forceps members are closed.
A space for preventing tissue from being lost formed between the opposed crocodile teeth, a pair of link members rotatably connected to a rear end of the forceps member, and An operation unit for opening and closing the forceps member via a link member, wherein the forceps member has an opening angle of at least 120 degrees.