JP2022055095A - Stent and stent delivery system - Google Patents

Abstract

To provide a stent and a stent delivery system that allow a position of the stent to be confirmed by using an endoscope.SOLUTION: A stent delivery system 1 comprises an inner catheter 10, a stent 20, and an outer catheter 30. The stent 20 comprises a stent tube wall part 21, a stent insertion part 22, a stent opening part 23, and a position confirmation part 50 formed in a color different from a predetermined color of the stent 20, and having a predetermined length. The position confirmation part 50 is arranged on the side of a rear end of the stent 20. The position confirmation part 50 serves as a mark for confirming a body insertion position of the stent 20 when the stent 20 is viewed in an endoscope image.SELECTED DRAWING: Figure 3

Description

There is an application for application of Article 30, Paragraph 2 of the Patent Act. Published in Gastroenterological Endoscopy Published by Tokyo Medical Co., Ltd. in March 2020 On August 11, 2020, the website of the Japan Gastroenterological Endoscopy Society (99th Japan Gastroenterological Endoscopy) Published in the abstract collection of the general meeting of the society)

The present invention relates to a stent and a stent delivery system used for bile duct, pancreatic duct drainage and the like.

Stents and stent delivery systems used for bile duct and pancreatic duct drainage are known (Patent Document 1).

In Patent Document 1, a coil formed by winding a wire around an axis and an outer layer formed in a substantially tubular shape with a first resin material and provided on the outer peripheral side of the coil coaxially with the coil. , A medical stent that is formed in a substantially tubular shape with a second resin material and has an internal layer provided on the inner peripheral side of the coil coaxially with the coil, and maintains the property of being easily bent and having little elasticity. However, it is disclosed that the lumen is less likely to be crushed when bent, and the contrastability is improved without deteriorating physical properties such as flexibility and elasticity.

Further, as shown in FIG. 12, a mark 150 having an axial width w is formed at a position on the central portion side of the locking portion 124 of the stent, and the stent is formed when the mark 150 is visible under the endoscope. A stent 120 that can be placed at a target site by releasing the 120 is on the market.

International Publication No. 2011/118081

However, when a stent is placed in a predetermined position (affected area) using an endoscope (a flexible endoscope in the gastrointestinal region), the field of view of the endoscope is narrow and the operation is performed in a narrow space such as the digestive organs. There is a problem that it is difficult to place the stent in a predetermined position because it is necessary to perform the stent.

Further, in the conventional stent 120 on which the above-mentioned mark is formed, the width w of the mark 150 is short, so that the mark 150 is often overlooked when the stent 120 is out of the field of view of the endoscope. There was a point. In particular, since the mark 150 is formed on the central portion side of the locking portion 124, the sense of distance between the mark 150 and the locking portion 124 under an endoscope (relative of the locking portion 124 to the mark 150). There was a problem that it was difficult to grasp the specific position). As a result, it is not possible to determine at what position the mark 150 should be released on the screen of the endoscope, and there is a problem that it is difficult to accurately place the stent 120 at the target site.

In particular, the stent 120 displayed in the image of the endoscope when the stent 120 enters the field of view of the endoscope after the stent 120 is continuously inserted with the mark 150 out of the field of view of the endoscope. Although the portion of is located on the rear end side of the mark 150, it may be mistakenly recognized as a portion located on the tip end side of the mark 150 and kept pressed. As a result, there is a problem that the stent 120 may get lost (placed in a place different from the target site).

By the way, in the invention described in Patent Document 1, since the position of the proximal end portion of the stent can be confirmed under X-ray fluoroscopy by a coil, the stent that prevents the stent from straying or deviating from the narrowed portion of the duodenal papilla and the bile duct. It is a medical stent that can be locked and the stent can be easily recovered. Further, Patent Document 1 discloses that changing the coil pitch causes a difference in X-ray opacity, and the boundary position where the coil pitch is different can be visually recognized under fluoroscopy.

On the other hand, with the progress of medical technology, surgery for performing drainage using an ultrasonic endoscope (EUS) is attracting attention in order to reduce the burden on patients. Unlike conventional drainage via the duodenal papilla, such surgery (for example, endoscopic ultrasonography fistula plasty) penetrates the gastrointestinal wall of the stomach and duodenum and between the bile duct and pancreatic duct. It is connected with a stent. In this surgery, the posterior end of the stent must always be placed in the gastrointestinal tract, otherwise bile and pancreatic juice can leak into the abdominal cavity, resulting in severe peritonitis. In addition, since the gastrointestinal tract such as the stomach and duodenum is a luminal organ, it expands and contracts depending on the position of the endoscope and the state of insufflation. Nor can the posterior end be reliably placed in the gastrointestinal tract.

Therefore, for example, in the drainage under ultrasonic endoscopy, it is required to place a stent under the field of view of the endoscope as an indispensable condition. However, the ultrasonic endoscope has a problem that it is difficult to see the endoscope field as compared with a normal endoscope because the ultrasonic probe is attached to the tip of the optical system monitor. The medical stent described in Patent Document 1 utilizes the difference in X-ray permeability for the position confirmation of the stent, and its characteristics cannot be used for the position confirmation by an endoscope. Therefore, it has been desired to develop a stent having a position confirmation that can be used for a new medical technique.

In view of the above circumstances, it is an object of the present invention to provide a stent and a stent delivery system that can prevent invasion of a stent and confirm the position (release position) of the stent by using an endoscope. ..

As a result of diligent research on the above-mentioned problems, the inventor of the present invention has found the following epoch-making stents and stent delivery systems.

The first aspect of the present invention for solving the above-mentioned problems is a stent used for endoscopic surgery, which includes a stent tube wall portion, a hollow stent insertion portion surrounded by the stent tube wall portion, and a hollow stent insertion portion. The stent is provided with a stent opening arranged at both ends of the stent insertion portion, a locking portion provided at least on the rear end side of the stent tube wall portion, and a positioning portion provided at the locking portion, and the stent has a predetermined color. The position-identifying part is formed in a color different from a predetermined color, and the position-identifying part is in a stent, characterized in that it has a predetermined length.

Here, the "locking portion" refers to a portion for indwelling a stent at a predetermined position, and the location and shape thereof are not particularly limited. As the locking portion, for example, in the case of a pigtail type stent, it corresponds to a wound-shaped portion described later, and in the case of a flap-type stent, it corresponds to a flap-shaped portion described later and a portion of a stent facing the flap-shaped portion. do.

In the first aspect, the stent is inserted into the body under an endoscope, and the position confirmation portion can be visually recognized while looking at the image of the endoscope, so that the insertion position relationship of the stent in the body can be understood. In particular, unlike the conventional stent 120, the locking portion is provided with a position confirmation portion having a predetermined length (wide), so that even a part of the locking portion is displayed in the image of the endoscope. , The position confirmation unit can always be visually recognized. As a result, the position confirmation unit releases the stent when it is displayed on the image of the endoscope, so that the stent can be placed in an appropriate position. That is, it is possible to provide a stent that can prevent invasion and can confirm the position (release position) of the stent by using an endoscope.

In particular, color identification can be easily determined even by a non-experienced doctor. During the insertion of the stent, body fluids such as bile and pancreatic juice overflow from around the organs, making it difficult to secure a visual field and making it difficult to understand the positional relationship of the stent. However, in the stent of this embodiment, since the position confirmation portion has a predetermined length, the position confirmation portion can be easily found by the endoscopic image. In addition, it only forms a color different from a predetermined color, has a simple structure, and can provide a low-cost stent.

In the second aspect of the present invention, the position confirmation portion has at least one of a first extending portion extending toward the distal end side and a second extending portion extending toward the rear end side of the locking portion. The stent according to the first aspect, characterized in having.

In the second aspect, the length of the position confirmation portion can be adjusted according to the situation of the target site, the type and shape of the stent, and the like. As a result, it is possible to provide a stent in which the position (release position) of the stent can be easily confirmed by using an endoscope.

A third aspect of the present invention is described in the first or second aspect, wherein the position confirmation unit is formed of a plurality of short position confirmation units shorter than a predetermined length of the position confirmation unit. It is in the stent of.

In the third aspect, since the position confirmation unit is formed by a plurality of short position confirmation units, the position confirmation unit can be more easily recognized. As a result, it is possible to provide a stent in which the position (release position) of the stent can be more easily confirmed by using an endoscope.

A fourth aspect of the present invention is described in any one of the first to third aspects, wherein the position confirmation portion is not provided in the vicinity of the stent opening on the rear end side of the stent. It is in the stent of.

In the fourth aspect, since the position of the stent opening on the rear end side can be visually recognized, it is possible to further prevent the stent from entering.

Further, when manufacturing a stent, the position confirmation portion may be colored after fixing the vicinity of the stent opening on the rear end side of the stent with a jig. In that case, the jig will hinder the coloring of the position confirmation portion. On the other hand, when the position confirmation portion is not provided in the vicinity of the stent opening on the rear end side of the stent, the jig does not inhibit the coloring in the vicinity of the stent opening of the position confirmation portion. As a result, the stent according to the present invention can be easily manufactured as compared with a stent in which a position confirmation portion is provided near the stent opening on the posterior end side of the stent.

A fifth aspect of the present invention is the stent according to any one of the first to fourth aspects, wherein the attention-calling portion is provided on the distal end side of the stent rather than the position confirmation portion. It is in.

In the fifth aspect, when the stent is inserted, the attention-calling part appears before the position-confirming part in the endoscopic image, so that the position-confirming part is expected to appear in the endoscopic image. be able to. As a result, since the speed of the stent insertion operation can be controlled, it is possible to further avoid the invasion of the stent.

A sixth aspect of the present invention is in the stent according to the fifth aspect, wherein the alerting portion is formed in a predetermined color and a color different from that of the positioning portion.

In the sixth aspect, the difference between the alerting unit and the position confirmation unit becomes clear, and the alerting unit can be found more accurately.

A seventh aspect of the present invention is in the stent according to the fifth or sixth aspect, wherein the alerting portion is formed of a plurality of short alerting portions.

In the seventh aspect, since the attention-calling portion is formed with a plurality of short position confirmation portions, it becomes easy to recognize the attention-calling portion.

In an eighth aspect of the present invention, the alerting portion is a stent at a distance of 1/3 of the length from the distal end of the locking portion to the distal end of the locking portion from the center of the stent. The stent according to any one of the fifth to seventh aspects, characterized in that it is formed at least over the portion of the above.

In such an eighth aspect, when the stent is extruded, a considerable amount of time is obtained until the alert portion appears on the endoscopic image, so that the stent can be released with a margin.

A ninth aspect of the present invention is any one of the fifth to eighth aspects, wherein the alerting portion is formed from the distal end portion of the locking portion to the central portion of the stent. It is in the stent described in.

In such a ninth aspect, when the stent is extruded, a sufficient time is obtained until the alert portion appears on the endoscopic image, so that the stent can be released with a sufficient margin.

A tenth aspect of the present invention is in the stent according to any one of the first to ninth aspects, wherein the locking portion has a wound shape.

In such a tenth aspect, a stent such as a double pigtail type or a single pigtail type according to the present invention can be provided.

An eleventh aspect of the present invention is in the stent according to any one of the first to ten aspects, wherein the locking portion is provided with a plurality of holes.

In the eleventh aspect, body fluids such as bile and pancreatic juice can be reliably introduced into the stent insertion portion.

A twelfth aspect of the present invention is in the stent according to any one of the first to ninth aspects, wherein the locking portion has at least a flap shape.

In such a twelfth aspect, a flap-type stent according to the present invention can be provided.

A thirteenth aspect of the present invention is in the stent according to any one of the first to twelfth aspects, wherein the endoscope is an ultrasonic endoscope.

In the thirteenth aspect, in the ultrasonic endoscope, the field of view of the endoscope can be seen as compared with a normal endoscope due to the structural reason that the ultrasonic probe is attached to the tip of the optical system monitor. It is possible to solve the problem of difficulty and provide a stent that can confirm the position (release position) of the stent using an endoscope.

A fourteenth aspect of the present invention is in a stent delivery system comprising the stent according to any one of the first to thirteenth aspects.

In such a fourteenth aspect, it is possible to provide a stent delivery system that can prevent invasion and can reliably place a stent at a target site by using an endoscope.

It is a schematic side view which shows an example of the stent delivery system which concerns on this invention. The inner catheter of FIG. 1 is shown, (a) is a schematic side view, and (b) is a schematic cross-sectional view taken along the line AA of (a). The pigtail type of the stent of FIG. 1 is shown, (a) is a schematic side view, and (b) is a sectional view taken along the line AA of (a). The flap type of the stent of FIG. 1 is shown, (a) is a schematic side view, (b) is a schematic side view of a lateral bending type, and (c) is a schematic cross-sectional view taken along the line AA of (a) and (b). .. The outer catheter of FIG. 1 is shown, (a) is a schematic side view, and (b) is an A-schematic A sectional view of (a). It is a schematic diagram which shows an example of placing a stent in a target site using the stent delivery system which concerns on this invention. It is a schematic side view which shows Example 1 of the position confirmation part of the stent of this invention, (a) is a pigtail type, (b) flap type. FIG. 7 is a schematic side view showing the second embodiment of the position confirmation unit following FIG. 7, in which (a) is a pigtail type and (b) is a flap type. It is a schematic side view which shows the stent of this invention, (a) is a 1st embodiment, (b) is a 2nd embodiment. Following FIG. 9, (a) is a third embodiment, and (b) is a fourth embodiment. Following FIG. 10, (a) is a fifth embodiment and (b) is a sixth embodiment. It is a schematic side view of a conventional stent.

Hereinafter, embodiments of the stent and the stent delivery system according to the present invention will be described with reference to the accompanying drawings. The present invention is not limited to the following embodiments.

FIG. 1 is a schematic side view showing an example of a stent delivery system according to the present invention. 2A and 2B show an inner catheter of FIG. 1, where FIG. 2A is a schematic side view and FIG. 2B is a schematic cross-sectional view taken along the line AA of FIG. 1A. 3 shows the pigtail type of the stent of FIG. 1, where FIG. 3A is a schematic side view and FIG. 3B is a schematic cross-sectional view taken along the line AA of FIG. 1A. 4A and 4B show the flap type of the stent of FIG. 1, FIG. 4A is a schematic side view, FIG. 4B is a schematic side view of a laterally bent type, and FIG. It is a cross-sectional view. 5A and 5B show the outer catheter of FIG. 1, where FIG. 5A is a schematic side view and FIG. 5B is a schematic cross-sectional view taken along the line AA of FIG. 1A. An example of a stent and a stent delivery system will be described in detail with reference to FIGS. 1-5.

As shown in FIG. 1, the stent delivery system 1 of the present invention includes an inner catheter 10, a stent 20, and an outer catheter 30.

As shown in FIG. 2, the inner catheter 10 has an inner catheter tube wall portion 11 having an annular shape, an inner catheter insertion portion 12 surrounded by the inner catheter tube wall portion 11 and a cavity, and a contrast medium operated by a doctor or the like at one end. It includes an operation unit 40 provided with a port, a GW (guide wire) lumen, and an inner catheter opening 13 provided at one end opposite to the operation unit 40. A guide wire (not shown) penetrates the inner catheter insertion portion 12, and the stent 20 can reach the target site by in-body guidance of the guide wire.

Hereinafter, the direction of one end opposite to the operation unit 40 is referred to as the distal end side, and the stent 20 and the outer catheter 30 are also referred to as the distal end side. Further, the side opposite to the distal end side of the stent 20 is expressed as the rear end side, and the distal end side and the posterior end side are collectively referred to as both end sides.

The stent 20 is to be placed at a target site in the body, and as shown in FIGS. 3 and 4, the stent tube wall portion 21 having an annular shape and the stent insertion portion 22 surrounded by the stent tube wall portion 21 and having a cavity are formed. , A stent opening 23 arranged at both ends of the stent insertion portion 22, and a locking portion 24 formed on both ends of the stent 20 are provided.

Here, the stent 20 of the present embodiment is provided with a position confirmation portion 50 (see the diagonal line in FIG. 3) formed in a color different from a predetermined color of the stent 20 at the locking portion 24 on the rear end side. .. The position confirmation unit 50 serves as a mark for confirming the insertion position (release position) of the stent 20 in the body when the stent 20 is viewed on an endoscopic image.

There are a plurality of types of stents 20 having different shapes, but the pigtail type and the flap type will be described below as typical shapes.

The stent 20 shown in FIG. 3 is a pigtail type. The locking portions 24 are arranged on both ends of the stent 20, have a wound shape that is wound once, and are provided with a plurality of holes 25 that penetrate the stent tube wall portion 21.

In the pigtail type having the wound-shaped locking portion 24, it is necessary to provide an important hole 25 for discharging bile, pancreatic juice, etc. However, if there is a coil described in Patent Document 1, the coil is an obstacle. And cannot drain bile and pancreatic juice well. The position of the hole 25 is not particularly limited as long as it is formed in the locking portion 24.

Next, the stent 20 shown in FIG. 4A is a flap type. The locking portions 24 are arranged on both ends of the stent 20 and have a flap shape. The flap shape of the locking portion 24 is formed by partially cutting out the stent tube wall portion 21 and projecting the tip of the flap outward from the stent tube wall portion 21. In the present embodiment, the locking portion 24 includes not only the flap shape but also the stent tube wall portion 21 corresponding to the flap shape.

The stent 20 shown in FIG. 4 (b) has a flap type as in FIG. 4 (a), but has a laterally bent shape in which the rear end side is curved downward. Others are the same as in FIG. 4 (a).

Although it has been described that the locking portions 24 are provided on both end sides in the present embodiment, they may be provided only on the rear end side of the stent 20.

As the material of the stent 20, a metal or a resin is adopted, and a stainless steel, a cobalt-chromium alloy, a platinum-chromium alloy or the like is selected as the metal, and a polymer compound having no magnetism is selected as the resin. The metal generally has a mesh shape, and the metal may be coated with a resin (silicon, polyurethane, etc.).

As shown in FIG. 5, the outer catheter 30 has an outer catheter tube wall portion 31 having an annular shape, a hollow outer catheter insertion portion 32 surrounded by the outer catheter tube wall portion 31, and both ends of the outer catheter 30 are opened. It is provided with an outer catheter opening 33.

As shown in FIG. 1, the stent delivery system 1 is a system in which an inner catheter 10, a stent 20, and an outer catheter 30 are integrated, and may include a guide wire (not shown).

Since the total length of the inner catheter 10 is longer than the total length of the outer catheter 30, when the inner catheter 10 is inserted into the outer catheter insertion portion 32, the distal end side of the inner catheter 10 protrudes from the distal end side of the outer catheter 30. When the protruding portion is inserted into the stent insertion portion 22, the stent opening 23 on the rear end side of the stent 20 and the outer catheter opening 33 on the distal end side of the outer catheter 30 come into contact with each other or come close to each other. Since the length of the portion of the inner catheter 10 protruding from the distal end side of the outer catheter 30 is longer than the total length of the stent 20, the distal end side of the inner catheter 10 is arranged so as to partially protrude from the distal end side of the stent 20.

The inner catheter 10 and the outer catheter 30 are molded from a flexible resin material (for example, polyethylene, polyurethane, polyamide, etc.), but the material is not particularly limited.

FIG. 6 shows an example of placement of a stent 20 at a target site using the stent delivery system 1 of the present embodiment. An example of surgery is endoscopic transpapillary biliary drainage.

The stent delivery system 1 can transport the stent 20 to a target site in the body while looking at the image of the endoscope. For example, the stent 20 is inserted from the duodenum 100 into the common bile duct 101 via the papilla 102 and sent to the place where the bile duct cancer 103 is occurring. The operating doctor confirms the insertion position of the stent 20 by the position confirmation unit 50 while looking at the image of the endoscope, and arranges the stent 20 at the target site. After that, when it is confirmed that biliary drainage is performed, when the inner catheter 10 is pulled out, the movement of the stent 20 is stopped by the locking portion (flap) 24, and the stent 20 is placed at the target site. In the present embodiment, the flap type stent 20 is taken as an example, but the same applies to the pigtail type.

Next, the position confirmation unit 50 will be described in detail with reference to FIGS. 7 to 11. The stent tube wall portion 21 is formed in a predetermined color. The predetermined color is white, yellow, blue, and a light color or the like is used. The stent 20 of the present embodiment is provided with a position confirmation portion 50 having a color different from a predetermined color on the rear end side of the stent 20. Here, the different color is not particularly limited as long as it is different from the stent tube wall portion 21, and examples thereof include black, purple, brown, and red, and a dark color is preferable.

Further, in the conventional stent 120 as shown in FIG. 12, the mark 150 is formed on the central portion side of the locking portion 124, but the width w in the axial direction thereof is as short as several mm. As a result, when the stent 120 was out of the field of view of the endoscope, the mark 150 was often overlooked.

On the other hand, the position confirmation portion 50 in the present invention is formed in the locking portion 24 and has a predetermined length. The "predetermined length" is a length at which a doctor or the like can sufficiently confirm the presence of the position confirmation unit 50 by looking at the image of the endoscope during the stent insertion operation. The predetermined length may be, for example, the length of the entire locking portion 24, or the length of a part thereof. In the pigtail type, the total length of the position confirmation portion 50 is, for example, about 5 cm, but this depends on the size of the radius R of the winding portion. On the other hand, in the flap type, the total length of the position confirmation portion 50 is, for example, about 1.5 cm, which also differs depending on the size of the flap and the distance from the rear end of the stent to the rear end of the locking portion on the rear end side. ..

The stent 20 is placed so as to straddle between the two organs. For example, when placed so as to connect the duodenum and the bile duct through the nipple, the stent 20 is placed near the nipple in each organ with the tip of the stent 20 entering the bile duct through the nipple. It is detained by being locked by the stop portion 24. Endoscopic images are used during the surgery.

In the present embodiment, the stent delivery system 1 is used to guide the stent 20 to a target site and then indwell it. In the stent 20 of the present embodiment, since the position of the position confirmation portion 50 can be specified by the endoscopic image, the insertion operation of the stent 20 can be reliably performed and the stent 20 can be accurately placed at the target site. can. That is, since the position confirmation unit 50 is formed on the stent 20 of the present embodiment, the doctor or the like stops inserting the stent into the target site when the position confirmation unit 50 can be confirmed on the endoscopic image. Then, you can know that it is in a state to be released. As a result, the stent 20 can be accurately placed at the target site.

Here, the insertion of the stent 20 is not easy and requires considerable medical treatment, and in some cases, the tip of the stent 20 may go too deep beyond the target site, resulting in the invasion of the stent 20.

In Patent Document 1, X-ray images are used to confirm the difference in coil pitch, but in surgery using an endoscope, it is not sufficient to confirm the position of the stent 20 due to the difference in X-ray opacity. Therefore, it is also necessary to confirm the position on the endoscopic image. In particular, in endoscopic ultrasonographic fistula plasty using an ultrasonic endoscope, the invasion of the stent 20 is directly linked to the serious contingency of peritonitis, so the position is confirmed by endoscopic images. Is very important.

Further, Patent Document 1 discloses that the boundary can be specified even in appearance by the shade of hue caused by different coil pitches. However, for example, in endoscopic ultrasonographic fistula plasty using an ultrasonic endoscope, the structural reason that the ultrasonic probe is attached to the tip of the endoscope, and the bile and pancreatic fluid from the surroundings. It is very difficult to secure the field of view of the endoscope, and it is extremely difficult to confirm the boundary of the coil pitch.

The stent 20 and the stent delivery system 1 of the present embodiment can use an endoscope to identify the color of the position confirmation unit 50 on an endoscopic image. This color identification can be easily determined by non-experienced doctors.

7A and 7B are side views showing Example 1 of the position confirmation portion of the stent of the present invention, in which FIG. 7A is a pigtail type and FIG. 7B is a flap type. 8 is a side view showing the second embodiment of the position confirmation unit following FIG. 7, in which FIG. 8A is a pigtail type and FIG. 8B is a flap type. In addition, the example of the flap-shaped locking portion of FIGS. 7 (b) and 8 (b) is the linear type of FIG. 4 (b), and the positional relationship of the position confirmation portion is the same on the side of FIG. 4 (c). The direction bending shape type is omitted. The formation position of the position confirmation portion will be described with reference to FIGS. 7 and 8.

FIG. 7 shows an example in which the position confirmation portion 50 is provided in the locking portion 24 on the rear end side of the stent 20. In the present embodiment, the position confirmation unit 50 is provided in the entire locking portion 24, but in the locking portion 24, the location where the position confirmation unit 50 is provided can be selected according to the application.

FIG. 8 is an example in which the position confirmation unit 50 is further extended to the front end side and the rear end side. The region extending toward the distal end side will be referred to as a first extending portion 51, and the region extending toward the rear end side will be referred to as a second extending portion 52.

In the pigtail type of FIG. 8A, the region of the first extending portion 51 is preferably within the outer diameter R when the winding is formed, and the first extending portion 51 has the winding of the stent 20. It is particularly preferable that it is equal to the outer diameter R when formed. When the first extending portion 51 is formed equal to the outer diameter R when the winding of the stent 20 is formed, the stage (location) where the first extending portion 51 can be confirmed on the endoscopic image. When the stent 20 is released at, the outer diameter of the locking portion 24 is formed in the vicinity of the location. As a result, the stent 20 becomes difficult to move from the place, and the stent 20 can be placed at the target site more accurately.

Further, the region of the second extending portion 52 is preferably up to the stent opening 23 on the rear end side, but it is more preferable that the second extending portion 52 is not formed in the vicinity of the stent opening 23.

In the flap type of FIG. 8B, a first extending portion 51 and a second extending portion 52 are provided around the locking portion 24. In the flap type, the lengths of the first extending portion 51 and the second extending portion 52 differ depending on the length of the locking portion 24. If the locking portion 24 is long, the first extending portion 51 and the second extending portion 52 do not have to be so long, and if the locking portion 24 is short, the first extending portion 51 and the second extending portion 52 are long. Need to take.

In the first embodiment of FIG. 7 (b), the position confirmation unit 50 is provided corresponding to the locking unit 24, but in the second embodiment of FIG. 8 (b), the position confirmation unit 50 is the first. The extending portion 51 and the second extending portion 52 are included, and are formed longer than in the first embodiment. The lengths of the first extending portion 51 and the second extending portion 52 are selectable. That is, the length of the position confirmation portion 50 can be adjusted by either or both of the first extending portion 51 and the second extending portion 52. Further, only one of the first extending portion 51 and the second extending portion 52 may be formed.

Next, some embodiments of the position confirmation unit will be described with reference to FIGS. 9 to 11. As an example, the position confirmation portion is provided in the locking portion, and the extending portion which is a part of the position confirmation portion is omitted for convenience.

In the first embodiment of FIG. 9A, the position confirmation portion 50 is provided in the locking portion 24 at the rear end portion of the stent 20. The distal end side is inserted, for example, into the biliary tract, and the posterior end side is inserted, for example, into the gastrointestinal tract. The position confirmation unit 50 of the first embodiment is continuously formed without interruption of color between predetermined lengths. By constructing the stent 20 in this way, the position of the position confirmation portion 50 can be easily and clearly confirmed on the endoscopic image, so that the locking portion 24 can be reliably placed in one organ. can.

In the second embodiment of FIG. 9B, in the position confirmation unit 50, a plurality of short position confirmation units 50a shorter than the length of the position confirmation unit 50 of the first embodiment are appropriately spaced between predetermined lengths. It is kept and arranged. That is, the set of the plurality of short position confirmation units 50a is the position confirmation unit 50. Further, the length of each short position confirmation portion 50a may be gradually increased toward the stent opening 23 on the rear end side, for example, a gradation arrangement may be used. The length of each short position confirmation unit 50a and the arrangement interval can be appropriately changed. By configuring the stent 20 in this way, the position confirmation portion 50 is formed by a plurality of short position confirmation portions 50a, so that the position of the position confirmation portion 50 can be more easily and clearly defined in the endoscopic image. Since it can be confirmed, the locking portion 24 can be more reliably placed in one of the organs.

In the third embodiment of FIG. 10A, a warning unit 60 (FIG. 10 (FIG. 10)) is used to notify that the position confirmation unit 50 will soon appear during insertion of the stent 20 closer to the tip side of the stent 20 than the position confirmation unit 50. a) See diagonal dashed line). It is preferable that the alert unit 60 and the position confirmation unit 50 are continuously provided. The position on the distal end side of the alerting portion 60 is not particularly limited, but is 1/3 of the length from the distal end side of the locking portion 24 to the central portion of the stent 20 to the distal end side portion of the locking portion 24. If it is formed over a portion of the stent at a distance, a considerable amount of time can be obtained until the alert portion 60 appears in the endoscopic image, and it is preferable. It is particularly preferable that the alerting portion 60 is formed in the above direction because a sufficient time is obtained until the alerting portion 60 appears in the endoscopic image.

If it can be confirmed that the alert unit 60 has appeared, the insertion control of the stent 20 is started. Therefore, if the alert unit 60 and the position confirmation unit 50 are discontinuous, it may lead to an operational error. There is sex. Further, when the first extending portion 51 of the position confirmation portion 50 is provided, it is preferable that the first extending portion 51 and the alerting portion 60 are continuously provided. By continuously providing the first extending portion 51 and the alerting portion 60, it is possible to easily determine where the portion of the stent 20 is visible even in an endoscopic image having a narrow field of view. .. The caution unit 60 may be formed in a color different from or the same color as the predetermined colors of the position confirmation unit 50 and the stent 20, but slightly lighter than the color of the position confirmation unit 50.

The fourth embodiment of FIG. 10B is another embodiment of the alerting unit 60, and like the second embodiment, a plurality of short alerting units shorter than the length of the alerting unit 60 of the third embodiment. The parts 61 are arranged. That is, the set of the plurality of short alerting units 61 is the alerting unit 60. When the predetermined color of the stent 20 is yellow and the color of the short alert portion 61 is black, the color scheme is highly visible. Further, the length of each short warning unit 61 may be arranged so as to gradually increase toward the position confirmation unit 50. By configuring the alerting unit 60 with a plurality of short alerting units 61, the position confirming unit 50 and the alerting unit 60 can be clearly distinguished even if the color and material are the same as those of the position confirming unit 50. can. That is, the attention-calling portion 60 can be formed by the same material (color) and processing method as the position confirmation portion 50.

The fifth embodiment of FIG. 11A is a case where it is applied to the flap type. The position confirmation portion 50 is provided in the locking portion 24 arranged on the rear end side of the stent 20. Although it has been described that the position confirmation portion 50 is provided in the locking portion 24 including not only the flap shape but also the stent tube wall portion 21 corresponding to the flap shape in the present embodiment, the position confirmation portion 50 is provided only in the flap shape portion. It may be provided only on the stent tube wall portion 21. In the sixth embodiment of FIG. 11B, the alerting unit 60 is provided as in the third embodiment. Other embodiments are the same as those of the second embodiment and the fourth embodiment. By constructing the stent 20 in this way, the position of the position confirmation portion 50 can be easily and clearly confirmed on the endoscopic image, so that the locking portion 24 is more reliably placed in one organ. be able to.

The position confirmation unit 50 is a kind of marker for confirming the insertion position of the stent 20 under an endoscope, and may be a color different from a predetermined color of the stent 20, and the selected color is the same color or a plurality of colors. The color may change toward the posterior end face of the stent 20. The color change, arrangement, and the like can be appropriately selected, and the same applies to the alerting unit 60.

The position confirmation unit 50 is formed in two colors, the surface of the stent 20 is painted, the surface of the stent 20 is roughened, and the surface is processed, the stent 20 is coated, and the stent 20 and the position confirmation unit 50 are connected. It can be formed by such as.

For example, when biliary drainage is performed under the guidance of an ultrasonic endoscope and the stent 20 is placed at the target site, the tip side of the stent 20 is inserted and the position of the stent is confirmed by a fluoroscopic image or an endoscopic image. There is a possibility of 20 intrusions. In the case of the stent 20 of the present embodiment, the position confirmation portion 50 can be visually confirmed on the endoscopic image, the insertion position relationship of the stent 20 can be confirmed, and the insertion of the stent 20 is stopped by the visual recognition, so that the stent 20 is set as the target site. It can be placed accurately. Further, it can be understood that the position confirmation unit 50 will soon appear in the endoscopic image by the alert unit 60, and the speed of the insertion operation of the stent 20 can be controlled. That is, in the insertion operation of the stent 20, it is not easy to suddenly stop the insertion speed, but such an operation is ensured by visually recognizing the alerting unit 60.

The stent 20 of the present invention is a stent 20 used for drainage under an endoscope, and is a stent tube wall portion 21, a hollow stent insertion portion 22 surrounded by the stent tube wall portion 21, and a stent insertion portion 22. A stent is provided with stent openings 23 arranged at both ends, a locking portion 24 provided at least on the rear end side of the stent tube wall portion 21, and a position confirmation portion 50 provided on the rear end side of the stent 20. 20 is formed in a predetermined color, the position confirmation unit 50 is formed in a color different from the predetermined color, and the position confirmation unit 50 has a predetermined length.

By constructing the stent 20 in this way, the stent 20 is inserted into the body under an endoscope, and the position confirmation unit 50 can be visually recognized while looking at the image of the endoscope, so that the insertion position relationship of the stent 20 can be understood. , The target site of the stent 20 can be reliably placed. Color identification can be easily determined by non-experienced doctors. During the insertion of the stent 20, bile, pancreatic juice, etc. overflow from the surroundings, making it difficult to secure a visual field, and it is difficult to understand the positional relationship of the stent 20, but the position confirmation unit 50 has a predetermined length. Therefore, the position confirmation unit 50 can be easily found in the endoscopic image. Further, it is possible to provide a low-cost stent 20 which has a simple structure and only forms a color different from a predetermined color.

As one aspect of the stent 20 of the present invention, for example, the position confirmation portion 50 is a second extending portion 52 extending toward the distal end side and a first extending portion 51 extending toward the distal end side of the locking portion 24. Have at least one. By configuring the stent 20 in this way, the length of the position confirmation unit 50 can be adjusted, and even if the type and shape of the stent 20 are changed according to the situation of the target site, the position confirmation unit 50 has an appropriate length. Can be provided.

As one aspect of the stent 20 of the present invention, for example, the position confirmation unit 50 is formed of a plurality of short position confirmation units 50a shorter than a predetermined length of the position confirmation unit 50. This makes it easier to find the position confirmation unit 50.

As one aspect of the stent 20 of the present invention, for example, the position confirmation portion 50 is not provided in the vicinity of the stent opening 23 on the rear end side of the stent 20. When manufacturing the stent 20, the position confirmation portion 50 may be colored after fixing the vicinity of the stent opening 23 on the rear end side of the stent 20 with a jig. In that case, the jig will hinder the coloring of the position confirmation unit 50. On the other hand, when the position confirmation portion 50 is not provided in the vicinity of the stent opening 23 on the rear end side of the stent, the jig does not inhibit the coloring of the position confirmation portion 50 in the vicinity of the stent opening 23. As a result, the stent 20 in which the position confirmation portion 50 is not provided near the stent opening 23 on the rear end side is compared with the stent in which the position confirmation portion 50 is provided up to the vicinity of the stent opening 23 on the rear end side of the stent 20. And can be easily manufactured.

As one aspect of the stent 20 of the present invention, for example, a warning unit 60 is provided closer to the tip of the stent 20 than the position confirmation unit 50. By configuring the stent 20 in this way, it can be understood that the position confirmation unit 50 is approaching the insertion state that can be confirmed by the endoscopic image, the speed of the insertion operation can be controlled, and the stent 20 can be avoided from entering. can. During the insertion of the stent 20, bile, pancreatic juice, etc. overflow from the surroundings, making it difficult to secure a visual field and making it difficult to understand the positional relationship of the stent 20. However, due to the presence of the alerting portion 60, it is possible to perform a calm insertion operation of the stent 20.

As one aspect of the stent 20 of the present invention, for example, the alerting portion 60 is formed in a color different from that of the positioning portion 50. By configuring the stent 20 in this way, the difference between the alerting unit 60 and the position confirmation unit 50 becomes clear, and the alerting unit 60 can be found more accurately.

As one aspect of the stent 20 of the present invention, for example, the alerting portion 60 is formed by a plurality of short alerting portions 61. By configuring the stent 20 in this way, it is possible to facilitate the discovery of the alerting portion 60.

As one aspect of the stent 20 of the present invention, for example, the locking portion 24 has a wound shape. By constructing the stent 20 in this way, the present invention can be applied to the pigtail type stent 20 as well.

As one aspect of the stent 20 of the present invention, for example, the locking portion 24 is provided with a plurality of holes 25. By constructing the stent 20 in this way, body fluids such as bile and pancreatic juice can be reliably introduced into the stent insertion portion 22.

As one aspect of the stent 20 of the present invention, for example, the locking portion 24 has at least a flap shape. By constructing the stent 20 in this way, the present invention can be applied to the flap type stent 20 as well.

The stent delivery system 1 of the present invention includes the stent 20 described above. With this configuration, it is possible to provide a stent delivery system 1 that reliably indwells the stent 20 at a target site.

The present invention is not limited to the above-described embodiment, and can be appropriately modified, improved, and the like. In addition, the material, shape, size, numerical value, form, number, arrangement location, etc. of each component in the above-described embodiment are arbitrary as long as the present invention can be achieved, and are not limited. For example, the locking portion may not have a hole formed.

The stent and stent delivery system of the present invention are most suitable in the field where it is desired to be able to reliably confirm the positional relationship of the stent through endoscopic images during stent insertion.

1 Stent delivery system 10 Inner catheter 11 Inner catheter tube wall 12 Inner catheter insertion part 13 Inner catheter opening 20, 120 Stent 21 Stent tube wall 22 Stent insertion part 23 Stent opening 24, 124 Locking part 25 holes 30 Outer Catheter 31 Outer catheter tube wall 32 Outer catheter insertion 33 Outer catheter opening 40 Operation part 50 Position confirmation part 50a Short position confirmation part 51 First extension part 52 Second extension part 60 Attention part 61 Short attention part Outer diameter when R winding is formed 100 Duodenal 101 Total bile duct 102 Papillary head 150 Mark

Claims (14)

A stent used for endoscopic surgery
Stent tube wall and
A hollow stent insertion part surrounded by the stent tube wall,
Stent openings arranged at both ends of the stent insertion portion and
A locking portion provided at least on the rear end side of the stent tube wall portion, and a locking portion.
A position confirmation portion provided in the locking portion is provided.
The stent is formed in a predetermined color, and the position confirmation portion is formed in a color different from the predetermined color.
The position confirmation unit has a predetermined length.
Stent. The positioning portion is characterized by having at least one of a first extending portion extending toward the distal end side and a second extending portion extending toward the rear end side of the locking portion.
The stent according to claim 1. The position confirmation unit is characterized by being formed of a plurality of short position confirmation units shorter than the predetermined length of the position confirmation unit.
The stent according to claim 1 or 2. The stent is not provided with the position confirmation portion in the vicinity of the stent opening on the rear end side of the stent.
The stent according to any one of claims 1 to 3. A warning portion is provided on the distal end side of the stent rather than the position confirmation portion.
The stent according to any one of claims 1 to 4. The alerting portion is characterized in that it is formed in a color different from the predetermined color and the positioning portion.
The stent according to claim 5. The alerting portion is characterized in that it is formed of a plurality of short alerting portions.
The stent according to claim 5 or 6. The alerting portion extends from the distal end of the locking portion to the stent portion at a distance of 1/3 of the length from the central portion of the stent to the distal end of the locking portion. The stent according to any one of claims 5 to 7, wherein the stent is formed. The stent according to any one of claims 5 to 8, wherein the alerting portion is formed from the distal end side of the locking portion to the central portion of the stent. The locking portion is characterized by having a wound shape.
The stent according to any one of claims 1 to 9. The locking portion is characterized by being provided with a plurality of holes.
The stent according to any one of claims 1 to 10. The locking portion is characterized by having at least a flap shape.
The stent according to any one of claims 1 to 9. The stent according to any one of claims 1 to 12, wherein the endoscope is an ultrasonic endoscope. The stent according to any one of claims 1 to 13 is provided.
Stent delivery system.

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