JPH04146743A - High frequency snare and biopsy method using thereof - Google Patents

Abstract

PURPOSE:To surely cutting-remove the mucous of a desired region by installing a projection which can be sticked into the body space mucous, at a part of a snare loop. CONSTITUTION:The snare loop 21 of a high frequency snare 20 has a half moon shape, and a rivet 22 as projection is installed at the top edge part. Since a wire for forming the snare loop 21 is made of stainless steel in the ordinary case, the metal rivet 22 is installed at the top edge of the half moon shaped snare loop 4a in the conventional through soldering or welding. Since the high frequency snare 20 has the rivet 22 at a part of the snare loop 21, the rivet 22 is stuck into the mucous on the periphery, for a small focus (polyp) 24 in a degree of bulging-out, and the focus 24 can be surely held from the root, i.e., the desired region of the focus 24 in a proper area can be held by the snare loop 21. As the material for the rivet 22, is preferably used the metal such as tungsten and molybdenum which possesses the larger electric resistance than that of stainless steel (austenite) as the material for the conventional loop part.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is capable of reliably excising the mucous membrane of a desired region in a biopsy in which the raised mucous membrane of a body cavity is excised using a high-frequency snare. Concerning high frequency snare and biopsy method.

(Prior Art) Endoscopes were developed for the purpose of examining and diagnosing body cavities, but these days they are also used for biopsies and treatment. In this case, for example, if a polyp is discovered through an endoscopy, it is determined whether the polyp is cancerous or non-cancerous, and treatment is performed if necessary. Insert a high frequency snare. That is, the high-frequency snare excises a raised lesion such as a polyp and takes it out of the body. Such a biopsy is specifically called a polypectomy.

Figure 6 shows the appearance of the high frequency snare. In other words, the high-frequency snare 1 has a snare guide 2 made of stainless steel (made of plastic, for example) with an extremely small diameter that can be inserted into an endoscope and is flexible (made of plastic, for example).
A conductive snare loop (approximately 0.3 to 0.5 mm in diameter) 4 is passed through the wire 3 (austenitic) wire 3 in a loop shape, and the end facing the snare loop 4 is connected to the wire 3. This becomes the electrode section 5 for applying electricity.

Note that there are various shapes of the snare loop 4, examples of which are shown in FIGS. 7(A) to 7(C). The snare loop 4a shown in FIG. 7(A) is called a half-moon shape, and has the advantage that the size of the loop can be adjusted according to the size of the polyp. On the other hand, the snare loop 4b shown in FIG. 7(B) is
It is called a hexagonal shape, and has the advantage of being equally wide open on the left and right sides.

Furthermore, the snare loop 4c shown in FIG. 7(C) is called an elliptical shape, and is adapted to the shape of a normal polyp.

When performing polypectomy, first the endoscope 7 is inserted into the body cavity 6 of the subject P, as shown in FIG. Then, the high-frequency snare 1 is sent into the body cavity 6 through the endoscope 7,
While viewing the endoscope 7, the snare loop 4 is hooked onto a raised lesion 8 such as a polyp within the body cavity 6. Thereafter, by pulling the wire 3 while leaving the snare loop 2 in the same position, the target lesion 8 is bound between the snare loop 4 side end of the snare loop 2 and the snare loop 4. Next, by passing a high frequency current through the wire 3 via the electrode section 5 connected to the high frequency power source 9, the lesion 8 bound by Joule heat or the like is cauterized. The cauterized lesion 8 was similarly inserted into the body cavity through the endoscope using appropriate grasping forceps (not shown).
Extract it from the body along the route shown by the broken line.

(Problems to be Solved by the Invention) However, not all lesions and lesions observed with an endoscope are elevated. For example, for early cancer, Figure 9 (
In addition to the raised type (type I) polyp shown in A),
Surface-type lesions as shown in Figures (B) to (D) (referred to as surface raised type (na type), surface flat type ('IIb type), and surface depressed type (IIc type), respectively), Figure 9 ( E)
The concave type (■ type) shown in Figure 9 (F), respectively.
and type IIc+III shown in (G), and ]Ia+II
There is a type c lesion.

Therefore, such lesions that are flat, depressed, or have a small degree of prominence are difficult or impossible to excise with the above-mentioned polypectomy.

Therefore, in order to sample lesions that are difficult to remove using conventional polypectomy, a biopsy method called strip biopsy, the steps of which are shown in FIGS. 10(A) to (H), was developed. Figures 10 (A) to (D) are cross-sectional views of the lesion at each step of the strip biopsy.
Figures 0 (E) to (H) are Figures 10 (A) to (D), respectively.
FIG. 3 is a plan view of the lesion at each step of the strip biopsy corresponding to FIG.

That is, the strip biopsy is as shown in FIG. 10 (A).
As shown in (E), for example, to a flat lesion of early gastric cancer, first, physiological saline or ethanol is injected into the submucosal layer 12 located under the mucous membrane 11 with an injection needle 10 through an endoscope (not shown). inject.

Then, as shown in FIGS. 10(B) and 10(F), the physiological saline 13 and the like accumulate in the submucosal layer 12, causing the mucous membrane 11a of the lesion to bulge. Therefore, this raised mucous membrane 11
a can be likened to a polyp.

After this, as shown in FIGS. 10(C) and (G), similar to the polypectomy described above, the high-frequency snare 1 is inserted through the endoscope, and the raised mucous membrane 11a is tied up with the snare loop 4 in the manner described above. Cauterize. At this time, the grasping forceps 14 are also inserted through the endoscope, and the raised mucous membrane 1 is
Grip 1a.

Finally, as shown in FIGS. 10(D) and (H), the cauterized mucous membrane 11a is removed together with a portion of the submucosal layer 12 using grasping forceps 14.

However, since the binding of the mucous membrane by the high-frequency snare 1 is based on mechanical force, the snare Loop 4 may not be able to sufficiently tighten the mucous membrane of the target area. That is, the snare loop 4 may not be able to properly hook the polyp and may come off, or may be able to bind only a narrower area than the intended area. In this case, a long period of time may elapse while the snare loop 4 is repeatedly redone due to its dislodgement, which may cause various adverse effects, and even if the snare loop 4 is cauterized, the amount of tissue remains insufficient to be used as a biopsy tissue piece. It may be impossible to collect the sample, which may impede diagnosis.
Furthermore, during treatment, for example, cancer tissue may remain and a complete cure may not be possible.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a high-frequency snare and a biopsy method that can reliably excise mucous membranes in a desired area.

[Structure of the invention]

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention is directed to a body cavity that is delivered through an endoscope, and a part of the body cavity mucous membrane is tied up with a snare loop.
To provide a high-frequency snare for cauterization, characterized in that a part of the snare loop is provided with a protrusion that can pierce the mucous membrane of a body cavity.

The present invention also provides a high-frequency snare that is delivered into a body cavity through an endoscope and binds and cauterizes a part of the body cavity mucous membrane with a snare loop, characterized in that the snare loop is made of a magnetic material.

The present invention further provides a biopsy method in which lines of magnetic force are applied to the snare loop from outside the body in a biopsy using a high-frequency snare in which the snare loop is a magnetic material.

(Function) In the high-frequency snare of the present invention, a portion of the snare loop is provided with a protrusion that can pierce the body cavity mucous membrane, or the snare loop is made of a magnetic material. Therefore, when the snare loop is hooked onto the raised mucous membrane, the protrusion can be used to pierce the raised mucous membrane or its surroundings. Therefore,
Even if the mucous membrane is insufficiently raised, the snare loop will not come off or be able to surround only a narrower area than the desired area, and the desired lesion can be reliably bound. On the other hand, a high-frequency snare using a magnetic snare loop applies magnetic lines of force from outside the body toward the snare loop when binding the raised mucous membrane. Therefore, the magnetic snare loop is pressed against the body cavity wall around the raised mucosa by interaction with the magnetic field lines.

Therefore, the snare loop can reliably capture and cauterize the raised mucous membrane in the desired area.

(Example) The present invention will be described in detail below with reference to FIGS. 1 to 5.

FIG. 1(A) is a front view of the tip of a high frequency snare 20 according to a first embodiment of the present invention. The configuration other than the snare loop 21 is the same as the conventional one shown in FIG.
Corresponding parts are given the same reference numerals and detailed explanations will be omitted.

That is, the snare loop 21 of this high-frequency snare 20 has a half-moon shape, but has a stud 22 as a protrusion at the tip end. Since the wire forming the snare loop 21 is usually made of stainless steel, the snare loop 21 is similar to that shown in FIG. 1(B).
As shown in FIG. 2, a metal stud 22 is attached to the tip of a conventional half-moon-shaped snare loop 3a by soldering or welding. Note that the rivet 22 has a sharp needle shape and can pierce the body cavity mucous membrane, but is not limited to this as long as it is a protrusion that can pierce the body cavity mucosa. Further, the mounting position of the rivet 22 is not limited to the leading edge of the snare loop 21, but may be mounted at other locations.

By the way, the stud 22 shown in FIG. 1(A) is attached to the snare loop 2.
When pushing forward the stud 22, it pierces around the lesion surrounded by the snare loop, but the stud 22 does not necessarily need to be attached outward from the snare loop 21 in this way. It may be attached to the inside of the snare loop 21, like a high frequency snare 23 according to a second embodiment of the present invention shown in FIG. In this case, when the snare loop 21 is pulled toward the lesion surrounded by the snare loop 21, the stud 22 pierces the lesion surrounded by the snare loop 21.

Note that the shape of the snare loop is not limited to a half-moon shape, but also a hexagonal shape,
Any shape such as an oval shape can be used.

FIG. 3 is a sectional view of an apparatus for performing a strip biopsy using the high frequency snare 20 of this embodiment. Since the configuration of this device is not substantially different from that shown in FIG. 8, corresponding parts are given the same reference numerals and a description thereof will be omitted.

This high frequency snare 20 has a stud 2 attached to a part of the snare loop 21.
2, the lesion (polyp) has a small degree of prominence.
24 as well, the rivet 22 is pierced into the surrounding mucous membrane, and the lesion 24 can be reliably grasped from the root, that is, the desired area of the lesion 24, with the snare loop 21 without being too narrow.

Note that a high-frequency current is sent from a high-frequency power supply (not shown) through the electrode portion 5 of the high-frequency snare 20, and the snare loop 21 is
It is known that when heating the lesion 24 to cauterize the lesion 24, the current density becomes particularly high at a sharp portion such as the rivet 22. Therefore, if the resistance value does not differ between the loop portion of the snare loop 21 and the stud 22, there is a risk that the surroundings of the lesion 24 pierced by the stud 22, that is, the tissue that is not the lesion, will be cauterized.

Therefore, in order to avoid such a situation, it is preferable to use a metal such as tungsten or molybdenum, which has a higher electrical resistance than stainless steel (austenite), which is usually the material of the loop portion, as the material of the stud 22. Note that even if both the loop portion and the stud 22 are made of materials with relatively low resistance, the same effect can be obtained by coating only the stud 22 with a material that has high resistance to high frequencies, such as ceramic or plastic resin. Obtainable. In this case, the loop portion and the stud 22 may be integrally molded from the same material.

In addition, as shown in FIG.
If the rivet 22 is attached toward the center, the rivet 22 will only pierce the lesion to be cauterized, so there is no need for any special measures to change the resistance value at the protrusion and loop portion as described above.

FIG. 4 shows a high frequency snare 30 according to a third embodiment of the present invention.
FIG. 2 is a cross-sectional view of an apparatus for performing a strip biopsy using the . Since the configuration of this device is also not substantially different from that shown in FIG. 8, corresponding parts are given the same reference numerals and a description thereof will be omitted.

In this high frequency snare 30, a snare loop 31 is made of a ferromagnetic material such as ferritic stainless steel. Therefore, when this snare loop 31 is pressed against a lesion 24 with a low prominence, as shown in the figure, when the magnet 32 (the direction of the root of the lesion 24 is the N pole) approaches from the root direction of the protruding lesion outside the body, as shown in the figure, The snare loop 31 is attracted to the magnet 32 by the action of magnetic lines of force and pressed against the body cavity wall at the root of the lesion 24.

Therefore, according to the high-frequency snare 30 of this embodiment, even if the lesion 24 has a small degree of protrusion, the snare loop 31 is crimped to the root of the lesion 24 so as not to come off, and the lesion 24 is removed from the root, that is, the desired area of the lesion 24. can be cauterized. In the high-frequency snare 30 of this embodiment, in order to bring the north pole of the magnet 32 closer to the snare loop 31, if the snare loop 31 is magnetized to the south pole, a stronger attractive force is generated between the snare loop 32 and the snare loop 31. The effect can be further improved by increasing the degree of compression of the loop 31 against the body cavity wall.

FIG. 5 shows a high frequency snare 35 according to a fourth embodiment of the present invention.
FIG. 2 is a cross-sectional view of an apparatus for performing a strip biopsy using the . Since the configuration of this device is also not substantially different from that shown in FIG. 8, corresponding parts are given the same reference numerals and a description thereof will be omitted.

In this example, it is assumed that the lesion 36 is located in a position where it is difficult to approach the magnet from the root direction. Therefore, in this case, the snare loop 37 is magnetized, for example, to the south pole, and the south pole of the magnet 38 is brought close to the lesion 36 from the top direction. Then, the snare loop 37 is repelled between the magnet 38 and pressed against the body cavity wall at the base of the lesion 36. Therefore, in this embodiment as well, the snare loop 31 is crimped to the base of the lesion 36 with a small degree of protrusion so that it does not come off, and the lesion 36 is
6 can be cauterized from the root, ie, the desired area of the lesion 36.

Note that in the third embodiment described above, the snare loop 31 is
In addition to magnetizing the lesion, if the magnet is brought close to the lesion with the S pole facing the lesion from the top direction as in the fourth embodiment, in addition to the attractive force of the magnet from the root direction of the lesion, the top of the lesion will be magnetized. Since the repulsive force of the magnet is also applied in this direction, the snare loop can be pressed against the body cavity wall extremely firmly.

〔Effect of the invention〕

As explained above, according to the present invention, in biopsies including polypectomy and strip biopsy, the snare loop can be prevented from dislodging even if the degree of protuberance is insufficient, or the snare loop can only surround a narrower area than the desired area. , it is possible to reliably bind and cauterize the target lesion in a short period of time.

[Brief explanation of the drawing]

FIG. 1(A) is a front view of the tip of a high-frequency snare according to a first embodiment of the present invention, FIG. 1(B) is a process diagram for manufacturing this high-frequency snare, and FIG. A front view of the tip of the high frequency snare according to the second embodiment, FIG. 3 is the first embodiment of the present invention.
4 and 5 are cross-sectional views of a strip biopsy device using a high-frequency snare according to the fourth and Jth embodiments of the present invention, respectively. Figure 6 is an overall front view of a conventional high-frequency snare, Figures 7 (A) to (C) are front views showing each shape of the high-frequency snare loop, and Figure 8 is a cross-section of a polypectomy device using a conventional high-frequency snare. 9A to 9G are cross-sectional views of various forms of lesions in early stage cancer, and FIGS. 10A to 10H are process diagrams showing each step of strip biopsy. 2... Snare loop, 5... Electrode part, 21... Snare loop, 22... Stud, 24.36... Lesion, 3
2゜38...Magnet. Applicant's agent Hatano Submitted drawings Figure 6 (A) (C) Figure (A) (E) CB') (F) Figure 10 (C) rD>

Claims (1)

[Claims] 1. In a high-frequency snare that is sent into a body cavity through an endoscope and binds and cauterizes a part of the body cavity mucous membrane with a snare loop,
A high-frequency snare characterized in that a portion of the snare loop is provided with a protrusion that can pierce the mucous membrane of a body cavity. 2. In a high-frequency snare that is sent into a body cavity through an endoscope and binds and cauterizes a part of the body cavity mucosa with a snare loop,
A high-frequency snare featuring a magnetic snare loop. 3. A biopsy method using the high-frequency snare according to claim 2, in which lines of magnetic force are applied to the snare loop from outside the body.