JP7624285B2 - Clip-on traction device - Google Patents

Description

The present invention relates to a novel clip-type traction device.

In recent years, endoscopic surgery (endoscopic surgery) using an endoscope has been widely used instead of open surgery, for reasons such as the relatively small burden on the patient and the small incisions made during surgery. For example, in the esophagus, stomach, large intestine, etc., for early cancer that remains localized without metastasis, a method is used in which a treatment tool is guided to the lesion site through the treatment tool insertion passage of an endoscope and used to cut off the localized lesion site from the mucosa.

Such endoscopic resection techniques are broadly divided into three types: a) polypectomy, b) endoscopic mucosal resection (EMR), and c) endoscopic submucosal dissection (ESD).

Of these, method a) above involves tightening a metal ring called a snare around mushroom-shaped tumors, polyps, etc., and then either burning them off using high-frequency current or physically squeezing them out without using high-frequency current.

In the above method b), when it is difficult to snare the affected area, such as in the case of a flat tumor, saline or other liquid is injected into the submucosal layer of the affected area to raise the affected area, and a snare is placed on that area, after which it is either burned off using high-frequency current or physically squeezed off without using high-frequency current.

Method c) above is a method in which, when the lesion is large (usually 2 cm or more) and it is difficult to use a snare, a high-frequency knife is used to remove the submucosal layer while excising it.

Among these, in particular in the above c) endoscopic submucosal dissection (ESD), in order to completely remove the diseased tissue together with the surrounding non-diseased tissue, only the mucosal layer, which is the superficial layer of the digestive tract, is incised around the diseased tissue (mucosal layer incision), and after the submucosal layer is fully exposed, the submucosal layer is dissected from the muscularis propria layer located further below (submucosal dissection) to remove the lesion. In other words, the submucosal dissection is performed following the mucosal layer incision. More specifically, the procedure is performed through the following steps.

[Step 1] An endoscope is inserted into the digestive tract from outside the body, reached to the target site for resection, and the extent of resection is determined.
[Step 2] The mucosal layer, which is the superficial layer of the digestive tract wall, is incised to expose the submucosal layer so that the resection area can be completely removed.
[Step 3] The submucosa is peeled off with great care so as not to damage the muscularis propria layer underneath the submucosa. Then, steps 1 to 3 are repeated to completely remove the lesion.

However, generally, when dissecting the submucosal layer, complications such as bleeding or perforation, and in the case of the esophagus, pneumomediastinum, can occur, which in some cases can pose a life-threatening risk. In particular, in step 3 above, when dissecting the submucosal layer, part of the mucosal layer during the resection covers the area where the dissection is performed, making it difficult or impossible to directly view the area where the resection is performed. This can result in perforation due to damage to the muscularis propria, as well as bleeding due to blood vessel damage. Therefore, to perform ESD safely and reliably, the practitioner is required to have the appropriate experience and advanced techniques.

When excising diseased tissue by surgical laparotomy, one end of the diseased tissue can generally be grasped and fixed with the left hand, so the diseased tissue can be resected reliably and accurately with the right hand, which is the dominant hand. In contrast, when excising diseased tissue by normal ESD, if the dissection treatment tool guided from the treatment tool insertion passage of the endoscope is in the right hand, there is no treatment tool that corresponds to the surgeon's left hand, so to speak, to grasp and fix. Therefore, if the diseased tissue is in its current state, it must be excised in an unfixed state. In addition, there are situations in which the dissection and excision must be performed blindly, as part of the diseased tissue during the resection process covers and conceals the resection surface. Therefore, in ESD, if a blood vessel is damaged by a blind dissection operation, bleeding may occur, and if the resection and excision surface becomes deeper than necessary, perforation may occur. When such a problem occurs, it is difficult to ensure a sufficient field of view, so recovery is not easy, and the treatment is often difficult or delayed, leading to life-threatening situations.

In ESD and other procedures, a method known as clip traction has been proposed to use the surgeon's left hand to tow and fix diseased tissue during the resection process (Non-Patent Documents 1-3). This involves temporarily halting the process of resecting the diseased tissue and removing the endoscope from the body, then attaching a clip to forceps passed through the treatment tool insertion passage of the endoscope in advance, reinserting the forceps into the body with a thread tied to the clip, and grasping and fixing the diseased tissue with the clip. According to this method, the surgeon tows the diseased tissue (site to be resected) while manipulating the other end of the thread, which is outside the body and independent of the endoscope and outside the treatment tool insertion passage of the endoscope.

There is also a method in which the diseased tissue is grasped with a clip with a thread while passing through the endoscope treatment tool insertion passage, the endoscope is then removed from the body, and the endoscope is then reinserted to the site of the disease independent of the clip with the thread that grasped the diseased tissue (Patent Document 1, Non-Patent Document 4).

However, this type of clip traction method requires the use of a standard endoscope model that has only one treatment tool insertion passage, and the treatment tool insertion passage is occupied by the device used to incise the mucosal layer before the submucosal dissection operation.

In order to grasp the traction member that protrudes outside the endoscope over its entire length with a separate clip forceps, the clip forceps must be attached to a traction member that is independent of the endoscope insertion passage while passing through the treatment tool insertion passage of the endoscope. Therefore, in order to attach the clip forceps, the endoscope must be removed from the body once, as described above. In particular, in situations where insertion itself is not necessarily easy, such as the large intestine, the endoscope must be removed once, the clip forceps must be inserted through the treatment tool insertion passage, a suture must be attached, and then the endoscope must be reinserted, which imposes a heavy burden on both the therapist and the patient. In addition, since this process of removal and reinsertion takes a certain amount of time, it is difficult to use conventional clip traction methods in emergency situations, such as when it is necessary to traction the affected area during bleeding, unfold the bleeding area, and directly view it.

On the other hand, as a traction method that does not require the removal and reinsertion of the endoscope, a method of performing ESD using a member with a nylon loop attached to the gripping part (wing part) of the clip has been proposed (Non-Patent Document 5). In this method, as a method of performing traction from inside the body, a clip 30 is used as the clip body, which includes a clamping part 11 that can be closed or opened like scissors, and a tightening ring 12 for closing or opening the clamping part, as shown in FIG. 1A. As shown in FIG. 1B, the clamping part is closed by moving the tightening ring upward. A nylon loop 14 is attached to the clamping part of such a clip body. Then, as shown in FIG. 12, the end of the lesion site X being dissected in the digestive tract A is clamped by the clip 30, and then the free nylon loop 14 is grasped by a second clip 30' and driven into the inner wall of the digestive tract A (FIG. 13). This completes the traction of the lesion site X. Note that in FIG. 12, the lesion site is depicted in a lifted state for convenience (the same applies to FIG. 9 and FIG. 10 below).

However, the components used in this method are assumed to be able to pass through the forceps port (insertion passage for treatment tools) of the endoscope, which means that there are limitations on their size, shape, etc.

In addition, because the nylon loop 14 is attached to the clamping portion (clip wing portion) 11 of the above-mentioned member, even if it can pass through the forceps port of the endoscope, the following problem remains. That is, as shown in FIG. 13, if the lesion site X is clamped with the clip 30 and pulled via the nylon loop 14, when the lesion site X is viewed with the endoscope, the clip 30 hangs down between the endoscope and the lesion site, which may obstruct the view of the endoscope or interfere with the procedure.

JP 2017-60580 A

Yoshiki Koike, Dai Hirasawa et al., "Efficacy of the Thread Clip Traction Method in Esophageal ESD: A Randomized Controlled Trial," Journal of the Japan Gastroenterological Endoscopy Society Vol. 57 (1), Jan. 2015 Masaya Kamizato, Takashi Akai et al., "Effectiveness of the Clip Traction Method in Esophageal Endoscopic Submucosal Dissection," Chiba Medical Journal 87: 237-243, 2011 Tsuneo Koyama, Yuichi Kikuchi, Shigeki Toritani et al., "Expanding the indications for gastric EMR: Technique innovations and results aimed at en bloc resection based on size," Stomach and Intestines 2002; 37: 1155-61 Kaneka Corporation's endoscopic soft grasping forceps "ICHIGAN (registered trademark)" package insert (Medical device notification number: 27B1XO0O34000010 Medical device 25 Medical mirror General medical device 35524000) Takayuki Murase, Satoshi Maekawa, and Yoshiyoshi Yasuyasu "ESD using clips with threads: A simple clip method using Zeoclips" https://www.jstage.jst.go.jp > article > gee > _pdf

As described above, both internal and external traction methods have their own drawbacks.

On the other hand, it is also true that internal traction and external traction each have their own unique advantages. For example, the method of performing traction from outside the body has the advantage of being able to adjust the traction force. On the other hand, the method of performing traction from inside the body has the advantages of a) being able to freely set the traction direction, b) being able to perform traction at multiple sites, and c) not needing to remove or reinsert the endoscope.

Therefore, in order to utilize all of these advantages, there is a strong need to develop technology that can achieve both internal and external traction with a single treatment tool, but the reality is that such technology has not yet been developed.

Therefore, the main objective of the present invention is to provide a treatment tool that can achieve both internal and external traction when performing treatment with an endoscope.

The inventors conducted extensive research in light of the problems with the prior art and discovered that a traction device with a specific structure can achieve the above-mentioned objective, which led to the completion of the present invention.

That is, the present invention relates to the following clip-type traction device.
1. An instrument for clamping and pulling at least a lesion site in a body under endoscopic guidance,
(1) The device has (a) a clamping portion that can be opened, closed, or snapped open like scissors, and (b) a clip portion that includes a fastening means for opening and closing the clamping portion,
(2) One or more thread-like members having a loop portion are connected to the tail portion of the clip portion on the opposite side to the clamping portion,
(3) a) the connection between the tail portion and the thread-like member and/or b) the connection between the thread-like members can be released by opening the loop portion of the thread-like member.
A clip-type traction device characterized by:
2. The clip-type traction device according to claim 1, wherein a filamentous member having a loop portion with a length sufficient to at least traction a lesion site inside the body from outside the body is attached to the tail and/or the filamentous member connected to the tail.
3. The clip-type traction device according to claim 1 or 2, further comprising a sheath, and a part or the whole of the thread-like member is housed within a tube of the sheath.
4. The clip-type traction device according to claim 3, wherein the sheath is made of resin.

The present invention provides an instrument that can achieve both internal and external traction when performing treatment using an endoscope.

In particular, in the clip-type traction device of the present invention, one or more filamentous members having loops are connected to the tail of the clip portion on the opposite side of the clamping portion, and a) the connection between the tail and the filamentous member and/or b) the connection between the filamentous members can be released by opening the loop of the filamentous member. In particular, the filamentous members are connected to each other by passing through each other's loops, and the connection of the opened filamentous members can be released by opening one of the loops. This makes it relatively easy to select and switch between traction from inside the body (internal traction) and traction from outside the body (external traction) through an endoscope. As a result, in the present invention, both internal traction and external traction can be performed with a single instrument (treatment tool).

As mentioned above, there are two types of traction methods for performing ESD safely and efficiently: external traction and internal traction, each of which has its own advantages and disadvantages. However, currently, dedicated treatment tools are used for external traction and internal traction, and it is not possible to select external traction or internal traction with a single treatment tool, or to switch between the two traction methods. In actual medical practice, for example, during the removal of diseased tissue by ESD, situations may arise where it is desirable to change between the two traction methods due to the selection of both traction methods, adjustment of the traction force, or change of the traction direction, but it has been difficult to change easily up to now. In this respect, the clip-type traction device of the present invention allows for relatively easy switching between internal traction and external traction depending on the situation, making it possible to perform treatments such as ESD more safely and quickly.

In particular, when performing traction from within the body, the clip-type traction device of the present invention has a loop-shaped filament attached to the tail of the clip on the opposite side of the clamping part, so unlike Non-Patent Document 5 and others, the peeling part and the length direction of the device of the present invention are arranged in a substantially straight line, effectively reducing the risk of obstructing the field of view of the endoscope or causing problems in operation.

FIG. 1 is a diagram showing the basic configuration of a clip forceps. FIG. 2 is a schematic diagram of the device of the present invention in which an internal traction filament member and an external traction filament member are connected. 13A and 13B are diagrams showing a state in which the thread-like members are released from each other. 1A and 1B are diagrams showing specific examples of a loop portion in the device of the present invention. 11A and 11B are diagrams showing specific examples of a connected state of multiple thread-like members. 13 shows an example of a connection state between the tail of the device of the present invention and a thread-like member. FIG. 13 is a diagram showing a state in which a lesion site is being pulled by the instrument of the present invention via a filamentous member extending from the tip of an endoscope. FIG. 8 is a diagram showing the state after the endoscope has been removed from FIG. 7 . FIG. 13 is a view showing a state in which a lesion site is grasped with the instrument of the present invention and the filamentous member is freed. FIG. 10 is a diagram showing the state before the free thread-like member in FIG. 9 is gripped by a clip. FIG. 11 is a diagram showing the state in which the freed thread-like member in FIG. 10 is fixed and pulled in the digestive tract. FIG. 13 shows the state after a lesion is grasped with a conventional clip with a nylon loop and before the clip is grasped and pulled by healthy mucosa. FIG. 13 is a diagram showing the state in which the freed thread-like member in FIG. 12 is fixed and pulled in the digestive tract.

10 Clip portion 11 Clamping portion (wing portion)
12 Fastening means (or fastening ring)
13 Tail portion 13a Tail space portion 14 Nylon loop 15a, 15b, 15c, 15d Thread-like member 15L, 15L', 15aL, 15bL Loop portion 20 Clip-type traction device (device of the present invention)
30, 30' Clip A Digestive tract X Lesion or detached part Y Endoscope

The clip-type traction device of the present invention (the device of the present invention) is a device for clamping and traction at least a lesion site in a body under endoscopic guidance,
(1) The device has (a) a clamping portion that can be opened, closed, or snapped open like scissors, and (b) a clip portion that includes a fastening means for opening and closing the clamping portion,
(2) One or more thread-like members having a loop portion are connected to the tail portion of the clip portion on the opposite side to the clamping portion,
(3) a) the connection between the tail portion and the thread-like member and/or (b) the connection between the thread-like members can be released by opening the loop portion of the thread-like member.
It is characterized by:

In the present invention, "at least the lesion area" refers to the area that is retracted and excised by the device of the present invention, and includes cases in which only the lesion area is involved, as well as cases in which both the lesion area and the surrounding normal tissue are involved. Hereinafter, the above "at least the lesion area" is also referred to simply as the "traction area."

A. Configuration of the device of the present invention An outline of a configuration example of the device of the present invention is shown in Figure 2. As shown in Figure 2, the device of the present invention 20 has a clip part 10 including a clamping part 11 that can be opened and closed like scissors, and (b) a fastening means 12 for opening and closing the clamping part, and a thread-like member 15a having a loop part is attached to a tail part 13 on the opposite side of the clamping part of the clip part 10, and another thread-like member 15b having a loop part is connected to this thread-like member 15a. Note that, for convenience, in Figure 2, the thread-like member is shown as a representative example of an internal traction thread-like member 15a and an external traction thread-like member 15b, but is not limited thereto, and other thread-like members may be connected to the thread-like members 15a and 15b, or may be connected to the tail part 13.

As the fastening means 12, the shape is not limited, but a ring-shaped member as shown in FIG. 2 can be preferably used. Although not shown, the body of the clip passes through the ring part of the ring-shaped member. Then, by sliding the fastening ring as the fastening means 12 toward the clip part 10 while pulling the thread-shaped member 15a, etc., the clamping part 11 can be closed. This makes it possible to grasp the tissue of an internal organ (such as the digestive tract mucosa).

The thread-like members 15a and 15b are connected to each other by passing through each other's loops, and it is possible to release the connection between the opened thread-like members by opening one of the loops.

Figure 3 shows an example of a form in which the thread-like members 15a and 15b are connected to each other (tails and the like are not shown). For example, as shown in Figure 3A, the loop portion 15bL of the thread-like member 15b is opened by cutting the thread-like member 15b at point x, and as a result, the thread-like member 15b is pulled out from the thread-like member 15a in the direction a or b as shown in Figure 3B, and the thread-like members 15a and 15b can be separated. That is, it is possible to easily separate the two by cutting one of the thread-like members (i.e., opening the loop portion) without using a special separation part. In this way, the "connection" in the present invention refers to a connection on the premise that the connection of the opened thread-like members can be released by opening one of the loop portions. It is preferable that the loop portion can be opened by cutting one part of the thread-like member.

In the device 20 of the present invention shown in FIG. 2, the thread-like member 15b has a length sufficient to pull the towing portion from outside the body, and functions as an extracorporeal traction member. That is, the tissue inside the body can be pulled from outside the body (the oral cavity side or the anus side) via the thread-like member 15b. On the other hand, the thread-like member 15a can also be used as an internal traction member by taking advantage of its short length. Therefore, for example, the towing portion of a lesion in the digestive tract can be pulled with the thread-like member 15a fixed to the digestive tract mucosa around the opposing position.

The clip 10 and thread-like members 15a and 15b may be stored in a sheath (tube) so that the clip can be opened, closed, or closed by manipulating the distal end of the clip.

In FIG. 2, the thread-like member 15a and the thread-like member 15b are connected by passing through each other's loops, but this is not necessarily required. For example, each may be fixedly attached or connected separately and independently to the tail portion 13 of the clip 10.

As shown in FIG. 1A, the clip portion 10 itself is preferably one having a mechanism in which the clamping portion 11 is open before clamping, and the clamping ring 12 is moved upward to close the clamping portion 11 when clamping internal tissue. Therefore, as long as it has such a mechanism, there is no particular limitation, and clips used in publicly known or commercially available endoscopes can be used. Therefore, as commercially available clips, various clips can be applied, such as clips for closing or blocking perforations or fistulas, and clips used to stop bleeding in the digestive tract. In addition, the material of the clip portion (including the clamping ring) is also not particularly limited, and examples thereof include metals (including alloys) such as stainless steel.

One or more thread-like members having a loop are attached to the tail portion 13 on the opposite side of the clamping portion of the clip portion. In FIG. 2, one thread-like member 15a is attached to the tail portion 13.

Each thread-like member has a loop portion (ring). As shown in FIG. 3, each thread-like member 15a has a loop portion 15aL. By having the loop portion, the thread-like member can be easily and securely grasped with a clip, and the thread-like member can be fixed to any location inside the body with the clip. More specifically, by clipping any location inside the body with the wings of the clip open like scissors hooked onto the loop portion, the detached portion including the lesion site and its surrounding area can be retracted.

The number and shape of the loops contained in one filament are not particularly limited. For example, as shown in FIG. 4A, there is a filament consisting of one loop 15L like a rubber band, and as shown in FIG. 4B, there is a filament having multiple loops 15L, 15L' molded integrally.

The number of traction members that are connected to each other in a state where they pass through the loop portion of the other thread-like member and that are in a state where the connection is released when at least one of the loop portions is opened is the number of such loop portions, which is the number of thread-like members.

In the device of the present invention, as shown in FIG. 5, two or more thread-like members may be connected in series or parallel. "Series" refers to a state in which one loop portion is connected to another loop portion. "Parallel" refers to a state in which one loop portion is connected to two or more other loop portions. The connection form may be either series, parallel, or both. FIG. 5 shows various connection states of four thread-like members 15a, 15b, 15c, and 15d. These thread-like members may be for either internal or external traction.

In FIG. 5A, four thread-like members 15a, 15b, 15c, and 15d are connected in series. In FIG. 5B, four thread-like members 15a, 15b, and 15c are connected in series, and thread-like members 15c and 15d are connected in parallel. In FIG. 5C, four thread-like members 15a, 15c, and 15d are connected in series, and thread-like members 15b and 15c are connected in parallel. In particular, when connected in parallel, it is possible to change the traction from within the body to traction from another part of the body. That is, by cutting and opening the loop part of the thread-like member 15 used for traction from within the body, the other loop part of the thread-like member 15 becomes free while attached to the tail part of the clip. By grasping such a loop part with another clip and fixing it to the digestive tract wall of another part, the direction, strength, etc. of traction from the initial traction part from within the body to another traction part can be arbitrarily changed. This also makes it possible to switch, for example, from internal traction to external traction.

In FIG. 2, the thread-like member 15a can be a member (internal traction member) that is primarily used to fix and traction any part of the body. For this reason, the material is not limited as long as it has the strength to withstand traction, and can be, for example, synthetic fibers (polyamide, polyester, etc.), natural fibers (silk, etc.), and rubber (natural rubber, silicone rubber, etc.) used as sutures, as well as metal wires, etc.

The thread-like member 15a is connected to the tail 13 on the opposite side of the clamping portion of the clip portion 10. It is preferable that the tail 13 is the end on the opposite side of the clamping portion of the clip portion 10. This allows the clip body 10 and the thread-like member 15a to be positioned in a substantially straight line when pulled, effectively reducing the risk of the clip portion itself obstructing the practitioner's field of vision.

It is preferable that the connection between the thread-like member 15a and the tail portion 13 of the clip portion 10 can be untied by opening the loop portion of the thread-like member 15a. In other words, it is preferable that the thread-like member 15a is connected in a detachable state to the clip portion 10. This allows the thread-like member 15a to be easily removed by cutting and opening the loop when it is no longer needed. For example, FIG. 6 shows an enlarged image of part A in FIG. 2. As shown in FIG. 6, when the loop portion is formed by passing the thread-like member 15a through the space portion 13a formed in the tail portion 13 and closing the loop, the thread-like member can be pulled out by cutting one part of the loop portion and opening the loop. Other methods include a method of providing a hook portion on the thread-like member 15a and hooking the hook portion on the tail portion 13, and a method of temporarily fixing the thread-like member 15a to the tail portion 13 with an adhesive, a pressure-sensitive adhesive, or the like.

The size of the thread-like member 15a can be adjusted as appropriate depending on, for example, whether it is for internal or external traction, the part to be tractioned, the size, etc. For example, when it is used mainly for internal traction, the length when it is straightened without opening the loop can be set within the range of about 0.5 to 5 cm, but is not limited to this.

In addition to the thread-like member, the device of the present invention also has a thread-like member having a loop portion long enough to pull at least the diseased area in the digestive tract and the digestive tract mucosa from outside the body. This is connected to the tail portion and/or the thread-like member. In FIG. 2, such a thread-like member 15b is connected to thread-like member 15a.

The thread-like member 15b in FIG. 2 is a member (external traction member) used for traction from outside the body (e.g., outside the mouth). There are no limitations on the material of the thread-like member for external traction, so long as it has low toxicity to the living body and is strong enough to withstand traction. For example, synthetic fibers (polyamide, polyester, etc.), natural fibers (silk, etc.), and rubber (natural rubber, silicone rubber, etc.) used as sutures can be used, as well as metal wires, etc.

In the present invention, as shown in FIG. 2, it is preferable that the thread-like member 15b is connected to the thread-like member 15a. The thread-like member 15a and the thread-like member 15b may be attached to the clip portion 10 separately and independently without being connected to each other. The connection method can be appropriately selected depending on the shape of the thread-like member 15b, etc.

The shape of the thread-like member 15b is a loop (ring-like) shape as a whole, but may have a loop part in part. This allows the loop-shaped thread-like member 15b to be passed through the loop part of the thread-like member 15a and connected in a chain shape passing through each other's loop parts. This allows the thread-like member to be easily pulled out by cutting the thread-like member and opening the loop part when the thread-like member is not needed. When the thread-like member 15b is made into a loop shape, two or more loops may be connected like a chain passing through each other's loops, but from the viewpoint of the ease of the pulling operation as described above, it is preferable that the thread-like member 15b is composed of one loop. In addition, when connected, they can be connected in series and/or parallel in the same form as the case of the thread-like member shown in FIG. 5.

The length of the thread-like member 15b can be adjusted as appropriate depending on, for example, the patient's height, the part to be pulled, etc., but is not limited as long as it is long enough to be pulled from outside the body. For example, if the part to be pulled is the stomach of an adult or its surroundings, the length of the thread-like member when straightened without opening it can be set appropriately within the range of about 80 to 230 cm.

The device of the present invention can generally be used with part or all of the thread-like member housed within the sheath tube. That is, thread-like member 15a and thread-like member 15b are usually made of a soft thread-like material, and by housing them in a sheath (tubular member) with a certain degree of rigidity, the sheath can be easily loaded into the endoscope body. In this case, the clip portion of the device of the present invention may protrude part or all from the sheath, or may be completely housed in the sheath with the clip portion closed.

As the sheath, one that is generally used for endoscopes can be used. Such a sheath has a certain degree of rigidity and flexibility, and its rigidity allows it to be loaded into the endoscope body, while its flexibility allows it to follow the movement of the endoscope. There are no particular limitations on the material, and examples of the material include sheaths made of synthetic resins such as polyester, polyvinyl chloride, and polyurethane. The inner diameter of the sheath can also be appropriately selected depending on, for example, the type of filamentous member used, and can be set to, for example, about 0.5 to 5 mm. Commercially available products can also be used as these sheaths.

B. Use of the instrument of the present invention The instrument of the present invention is used when a lesion site in the body is pulled under an endoscope, and to that extent, the type of endoscope is not particularly limited. For example, the instrument can be applied to any of treatments using upper gastrointestinal endoscopes, small intestinal endoscopes, large intestinal endoscopes, bronchoscopes, cystoscopes, thoracoscopes, laparoscopes, etc. Therefore, the organs in the body to which the instrument is applied are also not particularly limited, and examples include the digestive tract such as the stomach, esophagus, large intestine, small intestine, duodenum, and bile duct, as well as the oral cavity, nasal cavity, pharynx, bronchi, ureters, and intraperitoneal organs. Among these, the instrument of the present invention can be suitably used for dissecting and pulling a lesion site of mucosal tissue in an internal organ (particularly the digestive tract). Therefore, the instrument can be suitably used for, for example, endoscopic submucosal dissection (ESD).

The following describes, with reference to the drawings, a typical example of using the device of the present invention to resect a lesion in the stomach.

First, prepare a clip-type traction device as shown in FIG. 2 as the device of the present invention, and house the thread-shaped member 15a and the thread-shaped member 15b in a synthetic resin sheath, and set it so that the clip portion 10 is exposed from the tip of the sheath.

In this state, the endoscope body Y is inserted into the patient's mouth, and the lesion and its surrounding area are dissected under the guidance of the endoscope. Next, as shown in FIG. 7, the inventive instrument 20 is released from the endoscope Y toward the dissected area X during or after dissection is complete, and the inventive instrument 20 clamps the dissected area X with the clamping portion 11, and passes through the treatment tool insertion passage of the endoscope Y and is connected to the hand-operated operating portion at the entrance to the endoscope treatment tool insertion passage outside the body.

When performing internal traction using the short filament 15a, the long filament 15b is not necessary, so the sheath and the loop of the filament can be cut to separate the filament 15b from the filament 15a, and only the filament 15b can be removed from the body.

After that, as shown in FIG. 10, another clip 30 is released from the treatment tool insertion passage (forceps insertion passage) (not shown) of the endoscope Y in an open state while gripping the thread-like member 15a toward the inner wall of the digestive tract A. When this clip 30 grips the inner wall of the digestive tract A, it is released from the clipping launcher. As a result, as shown in FIG. 11, the clip 30 hooks the thread-like member 15a of the inventive device 20 connected to the dissected portion (pulling portion) and clamps the inner wall of the digestive tract A in that state. As a result, the dissected portion X is pulled via the clip 30 anchored to the wall surface facing the dissected portion X and the thread-like member 15a.

On the other hand, when pulling from outside the body using the thread-like member 15b, the same operation as above is performed up to the state shown in FIG. 7. This results in the detached portion X, the thread-like member 15a, and the thread-like member 15b being connected to each other. One end of the thread-like member 15b is connected to the thread-like member 15a, and the other end extends outside the body.

Then, the endoscope and sheath can be pulled out of the body, and the endoscope and sheath can be pulled out of the body in the state shown in FIG. 8. When pulling out the endoscope and sheath, for example, the thread-like member 15b can be cut outside the body, and the endoscope and sheath can be removed from there. In this process, the order in which the endoscope and sheath are removed can be any order, and the thread-like member 15b can be cut after the endoscope and sheath are removed. The cut part of the thread-like member 15b is the end, and the end can be manually grasped outside the body to perform the traction operation. Alternatively, a loop auxiliary member connected to the end outside the body of the thread-like member 15b can be provided in advance, and the loop auxiliary member can be cut and the endoscope and sheath can be removed from there. In this case, it is not necessary to cut the thread-like member 15b. The end of the thread-like member 15b protruding outside the body can be pulled by the surgeon's fingers. This allows, for example, fine adjustment of the traction force, traction amount, etc.

As described above, the device of the present invention allows the selection of both internal and external traction appropriate to the situation, and further allows external traction to be switched to internal traction during treatment, and internal traction to be switched to external traction during treatment. To switch from external traction to internal traction, the thread-like member 15b is cut outside or inside the body, so that the end of the thread-like member 15a becomes free while being connected and fixed to the lesion site X by the clip clamping part 11, and the thread-like member 15a is further fixed to the inner wall of the digestive tract A by another clip. In this case, if multiple loop thread-like members are connected as shown in Figure 5, the thread-like member 15b used for external traction can be opened, and the thread-like member 15b used for external traction can be removed, and the freed loop thread-like member for internal traction can be used for internal traction.

On the other hand, to switch from internal traction to external traction, it is possible to use another device of the present invention. That is, after removing the thread-like member 15a from the clip that fixed it to the digestive tract wall A and leaving it in a free state, the loop of the thread-like member 15a can be pulled from outside the body in a similar manner to performing external traction using the device of the present invention. In this case, before removing the thread-like member 15a from the clip that fixed it to the digestive tract wall A, a connection state between the thread-like member 15a and the thread-like member for external traction may first be established, and then the thread-like member 15a may be removed from the clip that fixed it to the digestive tract wall A.

After the detached portion X has been pulled by the inventive device, the detached portion can be completely separated from the body by following normal procedures, and the resection of the lesion can be completed. The inventive device that is pulling the detached portion can then be removed from the body together with the inventive device. It is also possible to remove the inventive device from the detached portion and retrieve it separately from the detached portion, and then remove the detached portion alone.

In this way, by pulling the detached portion with the instrument of the present invention, it becomes possible to easily view the area to be resected, and it becomes easier to grasp the position and course of blood vessels more reliably. This makes it possible to more reliably avoid bleeding or perforation, and facilitates the resection operation. As a result, the time required for resection can be shortened, allowing for safe and reliable resection of early-stage gastrointestinal tumors, etc., while also reducing the burden on the patient.

The following examples are provided to more specifically explain the features of the present invention. However, the scope of the present invention is not limited to the examples. In these examples, the following procedures are described in order: internal traction method, external traction method, switching from external traction method to internal traction method, and switching from external traction method to internal traction method.

Example 1 (Traction from Within the Body)
An example of a surgical procedure in which early stage gastric cancer is removed by ESD using the instrument 20 of the present invention as shown in FIG. 2 will be described below.
The endoscope is orally inserted into the digestive tract and reaches the affected area of the stomach or its vicinity (target area for resection), and the extent of resection is determined. Then, the mucosal layer, which is the surface layer of the digestive tract wall (stomach wall), is incised so that the area can be completely removed, exposing the submucosal layer below the detached portion X. Then, the inventive device 20 as shown in Fig. 2 is loaded into the tube of the synthetic resin sheath.
Next, with the tip of the endoscope Y still positioned at the lesion site, the sheath equipped with the traction members is inserted into the endoscope, and the inventive instrument 20 is guided through the treatment tool passage of the endoscope to the vicinity of the dissected portion X. The clip portion 10 of the inventive instrument 20 is then brought out to clamp the end of the dissected portion X. At this time, the inventive instrument 20 is connected to the lesion site X via the endoscope passage. The sheath is then cut or removed, and the filamentous member 15b is cut, whereby the clip portion and the filamentous member 15a at its tail are detached from the endoscope Y. This state is shown in Figure 9. Figure 9 shows the state after the filamentous member 15b has been removed.
10, another clip 30 guided through the endoscopic treatment tool passage is used to grasp the loop portion of the filamentous member 15a of the inventive device, and while grasping the loop portion, the clip is driven into the surrounding digestive tract wall (e.g., normal tissue portion of the stomach wall).
As a result, as shown in Figure 11, when tension is applied to the dissected portion X by the inventive instrument 20 in the direction in which it is lifted (the direction in which the dissected portion is turned back into the digestive tract lumen), the submucosal layer is dissected without damaging the underlying muscularis propria. The dissected submucosal layer is turned back in order because it is subjected to a traction force. By repeating this series of operations, the lesion can be completely removed.
By the above-mentioned process, the lesion site to be pulled can be pulled up in the appropriate direction with an appropriate traction force, and the resection site can be exposed, which makes it possible to directly view the resection site and the blood vessels present in the resection site, and enables a safe resection. Even if bleeding or perforation occurs, the lesion site can be prevented from covering the bleeding site or perforation site by traction, so that operations for stopping the bleeding and closing the perforation site can be easily performed.
Even if the inventive instrument 20 obstructs the endoscopic field of view or the resection operation, the obstruction can be easily avoided by the following operations. For example, the traction member can be removed by guiding a commercially available pair of scissors forceps through the treatment tool insertion passage in the endoscope to the lesion site. Depending on the situation, it is also possible to use an electric scalpel and pass electricity through it to cut and remove the traction member.

Example 2 (External Traction)
As in Example 1, the inventive instrument 20 is inserted through the endoscope and the endoscopic treatment tool insertion passage and introduced into the digestive tract, and the end of the lesion site X is clamped by the clip portion 10 of the inventive instrument 20 as shown in Fig. 7. By removing the sheath and endoscope at this stage, the end of the lesion site X can be pulled from outside the body by the clip portion 10 and the thread-like members 15a and 15b. This state is shown in Fig. 8.
Next, the endoscope is reinserted orally. The endoscope is used to continue the dissection of the submucosal layer that has been exposed and visualized by traction, making it possible to safely and efficiently excise the lesion site X.

Example 3 (conversion from extracorporeal traction to intracorporeal traction)
After performing traction from outside the body as in Example 2 (FIG. 8), one part of the thread-like member 15b is cut to open the loop, and the thread-like member 15b is removed. As a result, the end of the thread-like member 15a becomes free while being clamped by the clip part 10 of the device 20 of the present invention at the end of the lesion site X (FIG. 9).
In this state, the other clip is used to fix the end of the thread-like member 15a to the digestive tract wall A in the same manner as in Example 1, thereby enabling traction from within the body (FIGS. 10-11). By continuing the submucosal dissection in this state, it becomes possible to safely and efficiently excise the diseased tissue.
In another embodiment, after performing traction from outside the body as in Example 2 (FIG. 8), without opening one loop of thread-like member 15b, another clip is used to fix the end of thread-like member 15a to the digestive tract wall A, and then one part of thread-like member 15b is cut to open the loop, and thread-like member 15b is removed. In this way, thread-like member 15b is in a tensioned state when it is cut, making it easy to grasp and cut thread-like member 15b.

Example 4 (Conversion from internal to external traction)
In a state where traction is being performed from within the body in the same manner as in Example 1 (FIG. 11), the clip 30 clamping the digestive tract wall A is removed from the digestive tract wall A, or the thread-like member 15a held by the clip 30 is cut, opened, and removed, so that the thread-like member 15a becomes free while attached to the end of the lesion site X via the attached clip part 10. Thereafter, the end of the free thread-like member 15a is clamped by the second inventive device 20' through the treatment tool insertion passage of the endoscope.
As described above, when the loop is opened by cutting the filamentous member 15a, the cut end of the filamentous member 15a may be clamped. Alternatively, if a spare filamentous member 15c (not shown) is connected in advance to the tail of the clip portion 10, it becomes easier to hold and pull the filamentous member 15c by grabbing the loop portion 15cL of the filamentous member 15c.
Next, the endoscope and sheath can be withdrawn in the same manner as in Example 2, allowing for switching to traction from outside the body. The endoscope is then reinserted, and while performing traction from outside the body, submucosal dissection can be continued, enabling safe and efficient resection.
In another embodiment, after performing traction from within the body as in Example 1 (FIG. 11), the thread-like member 15a is not set free, but the thread-like member 15a or the tail 13 to which it is connected is grasped by the second inventive device 20'. In this way, the connection of "thread-like member 15a of the first inventive device 20 or the tail 13 to which it is connected" - "clip 30' of the second inventive device 20'" - "thread-like member 15a' of the second inventive device 20'" - "thread-like member 15b' of the second inventive device 20'" is formed, and then 15a of the first inventive device is cut at an appropriate location to open the loop, thereby enabling extracorporeal traction.

Claims (4)

An instrument for clamping and pulling at least a lesion site in a body under endoscopic guidance,
(1) The device has (a) a clamping portion that can be opened, closed, or snapped open like scissors, and (b) a clip portion that includes a fastening means for opening and closing the clamping portion,
(2) One or more thread-like members having a loop portion are connected to the tail portion of the clip portion on the opposite side to the clamping portion,
(3) a) the connection between the tail and the thread-like member and/or b) the connection between the thread-like members is
In the connection of the above-mentioned a), a loop portion is formed by passing a filamentous member through a space formed in the tail portion and closing the space,
In the connection of the above b), each filament passes through the loop of the other filament,
(4) The connection can be released by cutting one part of the loop of the thread-like member to open it.
A clip-type traction device characterized by: The clip-type traction device according to claim 1, wherein a filamentous member having a loop portion with a length sufficient to traction at least an internal lesion from outside the body is attached to the tail and/or the filamentous member connected to the tail. The clip-type traction device according to claim 1 or 2, further comprising a sheath, and a part or all of the filament is housed within the tube of the sheath. 4. The clip-type traction device according to claim 3, wherein the sheath is made of resin.