JP6775915B2 - Stent delivery device - Google Patents

Description

The present invention relates to a stent delivery device used to place a stent in the body.

In recent years, in cases of unresectable malignant biliary stricture or obstruction that require biliary drainage, such as when transduodenal papilla approach is not possible, endoscopic ultrasonography-guided transduodenal (or transgastric) There are some reports of performing biliary drainage (EUS-BD) (hepatic). EUS-BD inserts an endoscopic ultrasound into the duodenum (or stomach) and punctures the common bile duct (or intrahepatic bile duct) from the duodenum (or stomach) wall with a puncture needle while observing ultrasonic images in real time. Then, after inserting the guide wire into the bile duct through this puncture hole, insert and indwell the bypass tube that connects the inside of the duodenum (or stomach) and the inside of the common bile duct (or intrahepatic bile duct) along the guide wire. It is a procedure. This procedure enables biliary drainage by implanting a bypass tube in the body.

As a bypass tube used for such EUS-BD, a self-expanding stent provided with a coating film may be used. The stent delivery device used in this case includes, for example, a catheter portion having an inner sheath and an outer sheath into which the inner sheath is slidably inserted, as described in Patent Document 1 below, and has an inner sheath. A stent is placed in a stent placement portion provided near the distal end of the sheath, the stent is held in a reduced diameter inside near the distal end of the outer sheath, and the proximal end side of the catheter portion is held. In the above, there is known a stent in which the diameter of the stent is expanded by sliding the outer sheath with respect to the inner sheath so as to pull it out.

For example, when bypassing the stomach and the intrahepatic bile duct, puncture with a puncture needle from the stomach wall through the abdomen to the intrahepatic bile duct, insert a guide wire to secure a route, and make a puncture hole in the catheter part. After expanding the distal end with a dilator or the like to the extent that the distal end can be inserted, the distal end (stent placement portion) of the catheter portion is inserted into the puncture hole, and in this state, the outer sheath is pulled out and the stent is released (exposed / By expanding the diameter), a stent is placed in the puncture hole.

Since the catheter part needs to follow the shape of the treatment tool guide tube of the endoscope and the shape of the lumen to be inserted, it is made of a soft material from the viewpoint of ensuring sufficient flexibility, and its tip (far). In the position end), a certain thickness is required to maintain the required strength, and it is difficult to insert it as it is into the puncture hole punctured by the puncture needle. Further, a tapered tip tip may be provided at the tip (distal end) of the catheter portion (inner sheath), but for the same reason, a relatively soft material is used, so that the puncture hole is not expanded. It is difficult to insert it as it is. Therefore, conventionally, it has been essential to perform puncture hole expansion work using a dilator after puncturing with a puncture needle and before inserting the catheter portion and indwelling the stent.

Japanese Unexamined Patent Publication No. 2012-139471

As described above, when the conventional stent delivery device is used, it is necessary to expand the puncture hole with a dilator to the extent that the catheter portion can be inserted before inserting the catheter portion into the puncture hole. It is necessary to insert the catheter through the treatment tool guide tube of the endoscope and remove it from the endoscope after dilating the puncture hole, which requires a lot of man-hours and takes a long time to perform the procedure. It was. In addition, it is necessary to remove the dilator from the endoscope after dilating the puncture hole, and it takes a certain amount of time from dilating the puncture hole with the dilator to inserting the catheter part. There was also the problem that it could leak inside.

The present invention has been made in view of such a point, and an object of the present invention is to provide a stent delivery device capable of reducing the work man-hours of the procedure for placing a stent and performing the procedure in a short time. ..

The stent delivery device according to the present invention
A stent delivery device in which a self-expanding stent is placed in a puncture hole in the wall of a luminal organ punctured by a puncture needle or a hole to be expanded including a narrowed portion in the lumen.
An inner sheath having a stent placement portion for placing the stent on the outer peripheral surface near the distal end thereof and the inner sheath are slidably inserted, and the stent placed in the stent placement portion is contracted. A catheter part having an outer sheath that holds it in a diameterd state,
It is composed of a substantially cylindrical member attached to the distal end of the inner sheath, has an outer diameter that can be inserted into the expanded hole, and is expanded when inserted into the expanded hole. It is characterized by including a dilator portion having a tapered portion that expands the hole to such an extent that the distal end portion of the outer sheath can be inserted.

In the stent delivery device according to the present invention, the dilator portion is preferably formed of a material having a shore D hardness of 40 or more.

In the stent delivery device according to the present invention, the outer diameter at a position 1 mm from the distal end of the dilator portion is set to 1.7 mm or less in diameter, the inner diameter is set to 1.0 mm or less in diameter, and the wall thickness is set to 0.35 mm or less. Is preferable.

According to the stent delivery device of the present invention, a tip having an outer diameter that can be inserted into the expanded hole, and when the stent is inserted into the expanded hole, the distal end of the outer sheath inserts the expanded hole. Since the dilator portion having a tapered portion that expands to such an extent is provided, the distal end portion of the catheter portion can be inserted into the dilator portion while the dilator portion expands the dilator portion.

In this way, the dilated hole can be expanded and the catheter portion can be inserted at the same time, and as in the prior art, the catheter portion is prepared independently of the stent delivery device before being inserted into the dilated hole. It is no longer necessary to insert the dilator through the treatment tool guide tube of the endoscope and remove it from the endoscope after the hole to be expanded is expanded, and the work man-hours can be reduced. You can save time. Further, since the dilated hole can be expanded and the catheter portion can be inserted at the same time, it is possible to reduce the leakage of bile and the like into the abdominal cavity.

It is a front view which shows the whole structure of the stent delivery apparatus of embodiment of this invention. It is a side view which shows the structure of the distal end part of the stent delivery apparatus of embodiment of this invention. It is a figure which shows the work (puncture) at the time of placing a stent in a puncture hole by using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the work (puncture hole formation) at the time of placing a stent in a puncture hole using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the work (guide wire insertion) at the time of placing a stent in a puncture hole by using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the work (start of insertion of a catheter part) at the time of placing a stent in a puncture hole by using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the work (in the middle of insertion of a catheter part) at the time of placing a stent in a puncture hole by using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the work (the catheter part insertion completion) at the time of placing a stent in a puncture hole by using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the work (in the middle of a stent release) at the time of placing a stent in a puncture hole by using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the work (stent release completion) at the time of placing a stent in a puncture hole using the stent delivery apparatus of embodiment of this invention. It is a side view which shows the structure of the dilator part of another embodiment of this invention. It is a side view which shows the structure of the dilator part of still another embodiment of this invention.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In the present embodiment, endoscopic ultrasonography-guided transgastric transhepatic biliary drainage (EUS-BD), that is, a bypass tube (self-expandable stent) that bypass-connects the stomach and the intrahepatic bile duct is placed. Will be described as an example. However, the present invention is not limited to those that bypass the stomach and the intrahepatic bile duct, and can be widely applied to those that bypass the luminal organ and other luminal organs such as the duodenum and the common bile duct. Further, the present invention is not limited to the case where such a bypass tube is placed, for example, transduodenal papillary biliary drainage (a stent is placed in a stenosis in the common bile duct), or in a lumen other than the common bile duct. It can also be applied to those in which a stent is placed in the stenosis.

First, refer to FIG. The stent delivery device 1 is connected to the elongated catheter portion 2 inserted into the patient's body (lumen) and the proximal end side of the catheter portion 2 via a treatment tool guide tube of an endoscope (not shown), and is connected to the body. It is configured to roughly include an operation unit 3 for operating the catheter unit 2 in the body from the outside, a guide wire 4, a stent 5 as an indwelling target, and a dilator unit 6. The vicinity of the distal end of the catheter portion 2 including the stent 5 may be curved depending on the shape of the site to be placed, but it is drawn linearly for convenience in the drawing.

The catheter portion 2 includes an inner sheath (inner tube) 21 having a distal end and a proximal end, and an outer sheath (outer tube) 22 having a distal end and a proximal end. Contrast-enhanced markers (not shown) are attached to the vicinity of the distal ends of the inner sheath 21 and the outer sheath 22, respectively. The position of the contrast marker is detected by X-ray fluoroscopy and serves as a marker in the body. For example, the contrast marker is formed of a metal material such as gold, platinum, or tungsten, or a polymer blended with barium sulfate or bismuth oxide. ..

The inner sheath 21 is made of a flexible elongated tube, and a guide wire 4 used as a guide for inserting the catheter portion 2 into the patient's body is inserted into the lumen thereof. After inserting the guide wire 4 into the body to secure a path between the outside and the inside of the body, the catheter portion 2 is pushed (advanced) along the guide wire 4 to make the distal end side of the catheter portion 2 the purpose of the body. Can be inserted into the site. The outer diameter of the inner sheath 21 (the portion where the stent 5 described later is arranged) is about 0.5 to 3.5 mm.

A fixing ring 25 is integrally fixed in the vicinity of the distal end of the inner sheath 21, and the fixing ring 25 is for defining the position of the proximal end of the stent 5, and is from the fixing ring 25. The part on the distal end side is the stent placement part. A stent 5 is arranged in the stent arrangement portion so as to cover the inner sheath 21. Further, another elongated tube (not shown) is coaxially provided on the portion of the inner sheath 21 proximal to the fixing ring 25 so as to cover the elongated tube constituting the inner sheath 21 main body. The portion of the inner sheath 21 on the proximal end side of the fixing ring 25 is thicker than the portion of the inner sheath 21 on the distal end side of the fixing ring 25. Since the portion of the inner sheath 21 on the proximal end side of the fixing ring 25 is thickened in this way, the pushability of the inner sheath 21 is increased and the operability is improved, and the position of the fixing ring 25 is proximal. It is prevented from shifting to the end side.

The outer sheath 22 is made of a flexible elongated tube, has an inner diameter slightly larger than the outer diameter of the inner sheath 21, and the inner sheath 21 is slidably inserted inside the outer sheath 21. The inner diameter of the outer sheath 22 is about 0.5 to 3.5 mm, and the outer diameter is about 1.0 to 4.0 mm. The outer sheath 22 can slide (relatively move) in the axial direction with respect to the inner sheath 21 by operating the operation unit 3.

Examples of the material of the inner sheath 21 and the outer sheath 22 include polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, polyester terephthalate, polybutylene terephthalate and the like, polyester, polyamide and polyether polyamide. , Polyester polyamide, polyether ether ketone, polyetherimide, various resin materials such as fluororesins such as polytetrafluoroethylene and tetrafluoroethylene / hexafluoropropylene copolymer, polystyrene-based, polyolefin-based, polyurethane-based, polyester Various thermoplastic elastomers such as based, polyamide-based, and polybutadiene-based can be used. Two or more of these can be used in combination.

Although not provided in the present embodiment, the outermost pipe (not shown) may be arranged coaxially on the outside of the outer sheath 22. The outermost tube consists of an elongated tube with flexibility and has a lumen into which the outer sheath 22 is slidably inserted. As the outermost tube, a tube having a size larger than the outer diameter of the outer sheath 22 by about 0.05 to 1.0 mm can be used. As the material of the outermost tube, polyacetal, polytetrafluoroethylene, tetrafluoroethylene / hexafluoropropylene copolymer, polypropylene and the like can be used.

The stent 5 is a self-expandable covered stent that expands from a contracted state by its own elastic force, and has a tubular bare stent formed by a frame and a coating film portion that covers the outer periphery of the bare stent. .. The bare stent is formed of a superelastic metal such as a nickel-titanium alloy, a cobalt-chromium alloy, a gold-titanium alloy, or a beta-titanium alloy, or a shape memory metal. The surface of the bare stent is covered with a coating film that spreads so as to fill the space between adjacent frames, and the outer periphery of the bare stent covered with the coating film is covered with a coating film portion such as a polymer film.

The total length of the stent 5 is determined according to the distance between the luminal organs to be bypassed, but is about 30 to 200 mm, and the outer diameter at the time of expansion is the type and size of the luminal organs to be bypassed. Although it is determined according to the bypass, it is about φ2 to φ20 mm. The outer diameter of the stent 5 when the diameter is reduced is about a fraction of the outer diameter when the diameter is expanded. In the present embodiment, the stent 5 is described as one of the constituent members of the stent delivery device 1, but the stent 5 may be replaceable as a separate member from the stent delivery device 1.

As shown in FIG. 1, the guide wire 4 is used as a guide for inserting the catheter portion 2 into the patient's body, is inserted into the lumen of the inner sheath 21, and its distal end is the inner sheath. Along with protruding from the opening at the distal end of the dilator portion 6 of 21, the proximal end thereof is exposed to the outside through the opening 21a at the proximal end of the inner sheath 21 arranged so as to penetrate the operation portion 3. It is located in. As the guide wire, one having a diameter of 0.035 inch (≈0.889 mm) and one having a diameter of 0.025 inch (≈0.635 mm) are generally used, but in the present embodiment, the guide wire is used. As the wire 4, a wire having a diameter of 0.035 inch shall be used.

The operation unit 3 has a substantially cylindrical release handle (housing) 31, and the opening on the distal end side of the release handle 31 is integrally provided with a distal end side lid member having a through hole in the central portion thereof. The opening on the proximal end side is closed by being attached, and the opening on the proximal end side is closed by integrally attaching the distal end side lid member having a through hole in the central portion thereof.

The proximal end of the outer sheath 22 is slidably inserted into the through hole of the distal end side lid member of the release handle 31, and the proximal end of the outer sheath 22 is located inside the release handle 31. A groove is formed on the side wall of the release handle 31 so as to penetrate inward and outward along the central axis thereof. In this groove, the foot portion of the release lever 32 having the head portion located on the outside of the release handle 31 and the foot portion erected in the central portion of the head portion is arranged through the groove.

The tip (lower end) of the foot of the release lever 32 is fixed to the proximal end of the outer sheath 22 located inside the release handle 31, and the release lever 32 is moved along the groove. The outer sheath 22 can be slid toward the proximal end side or the distal end side with respect to the inner sheath 21 fixed to the release handle 31 (proximal end side lid member).

The proximal end of the inner sheath 21 inserted through the outer sheath 22 passes through the release handle 31 and through the through hole of the proximal end side lid member of the release handle 31, and the proximal end thereof is the release handle. It is located outside 31. The inner sheath 21 is fixed to the proximal end side lid member (release handle 31) at the portion of the through hole.

When the release lever 32 is moved to the distal end of the groove, the distal end of the outer sheath 22 reaches the dilator portion 6, and in this state, the stent 5 arranged in the stent arrangement portion of the inner sheath 21 is placed. It is in a state of being held inside the reduced diameter state. When the release lever 32 is moved to the proximal end side of the groove from this state, the outer sheath 22 is slid toward the proximal end side with respect to the inner sheath 21, and the stent 5 is the distal end of the outer sheath 22. The stent 5 is released (diameter expanded) by a self-expanding force.

A dilator portion 6 is attached to the distal end portion of the inner sheath 21. The dilator portion 6 is a member having a function (dilation function) as a dilator that expands the catheter portion 2 to the extent that the catheter portion 2 can be inserted into the puncture hole that has been punctured by the puncture needle and has not been expanded. Therefore, in order to realize this function, it is necessary to have a hardness sufficient to expand the non-dilated puncture hole, and its tip (distal end) is thin enough to be inserted into the non-expanded puncture hole. There is a need.

In order to realize such a function, the dilator portion 6 of the present embodiment is composed of a substantially cylindrical member as shown in FIG. 2, and has a luminal organ wall (stomach wall in the present embodiment) and other luminal organs. A tip portion 61 having an outer diameter that can be inserted into a puncture hole punctured by a puncture needle at a wall (intrahepatic bile duct wall in this embodiment), a base end portion 62 attached to the distal end of the inner sheath 21, And, when inserted into the puncture hole, it has a tapered portion 63 that expands the puncture hole to such an extent that the distal end portion of the outer sheath 22 can be inserted. Further, the dilator portion 6 has a lumen (through hole) 6a communicating with the lumen of the inner sheath 21, and a guide wire 4 to be inserted into the inner sheath 21 is inserted into the lumen 6a. ..

The base end portion 62 includes a straight body portion 62a having an outer diameter substantially the same as the outer diameter of the outer sheath 22, and a small diameter portion 62b that is insertably inserted into the distal end portion of the lumen of the outer sheath 22. Have. The distal end of the inner sheath 21 is connected and fixed to the proximal end of the small diameter portion 62b. The proximal end of the tapered portion 62 is integrally connected to the distal end of the straight body portion 62a. The tapered portion 62 is formed in a tapered shape so as to become thinner toward the distal end, and the proximal end of the tip portion 61 is integrally connected to the distal end of the tapered portion 62. In the present embodiment, the outer shape of the tip portion 61 is formed in a tapered shape so as to become thinner toward the distal end side thereof, and the distal end of the tip portion 61 is an opening on the distal end side of the lumen 6a. Has reached. However, the tip portion 61 may have a straight body shape as long as the wall thickness on the distal end surface thereof is such that it can be inserted into the puncture hole.

Here, it is assumed that the inner diameter of the inner sheath 6a of the dilator 6 is set to be about the same as the inner diameter of the inner sheath 21, but the inner diameter of the inner sheath 6a of the dilator portion 6 is the same as the outer diameter of the inner sheath 21. The degree may be set so that the distal ends of the inner sheath 21 are inserted into the lumen 6a of the dilator portion 6 to fix them to each other. Further, the inner diameter of the lumen 6a on the proximal end side of the dilator portion 6 is about the same as the outer diameter of the inner sheath 21, and the inner diameter of the lumen 6a on the distal end side of the dilator portion 6 is the same as the inner diameter of the inner sheath 21. By providing a step in the cavity 6a of the dilator portion 6 and inserting the distal end portion of the inner sheath 21 into the cavity 6a of the dilator portion 6, the inner peripheral surface of the dilator portion 6 and the inner sheath are inserted. The inner peripheral surfaces of 21 may be fixed to each other so as to be substantially flush with each other.

The dimensions of each part of the dilator portion 6 are, for example, that the length La1 of the tip portion 61 in the central axis direction is in the range of 1 to 2 mm, and the length La2 of the base end portion 62 in the central axis direction is in the range of 1 to 5 mm. The length La3 of the tapered portion 63 in the central axis direction is set in the range of 2 to 10 mm, and the outer diameter of the straight body portion 62a is set in the range of 2 to 4 mm. In the present embodiment, the length La1 is 1 mm, the length La2 is 3 mm, the length La3 is 9 mm, and the outer diameter of the straight body portion 62a is 2.5 mm.

The dilator portion 6 can set the tip portion 61 to an outer diameter (and therefore thin) small enough to be inserted into the unexpanded puncture hole, and the tapered portion 63 makes the puncture hole of the outer sheath 22. It must be hard enough to provide the ability of the distal end to expand to the extent that it can be inserted. The hardness of the material forming the dilator portion 6 for realizing this is the Shore D hardness (based on ASTM D2240), which is preferably set to a hardness of 40 or more, more preferably 50 or more, and 70. It is most preferable to set the above.

Materials that satisfy the above hardness include PEBAX (registered trademark) 4033 (Shore D hardness 42) and PEBAX5533 (Shore D hardness 55), which are polyether blockamide copolymers manufactured by Arkema, and Nippon Polypro Co., Ltd. Made of polypropylene, Novatec (registered trademark) EA9 (Rockwell R hardness 100), Novatec EG6D (Rockwell R hardness 90), polypropylene (PP: Shore D hardness 50-90), Polytetrafluoroethylene (PTFE: Shore D) Examples thereof include polymer materials such as hardness 50 to 60), polyether ether ketone (PEEK: Rockwell R hardness 120), and various metal materials such as stainless steel. The correspondence between the Rockwell R hardness and the shore D hardness is an approximation, but the Rockwell R hardness 50 corresponds to the shore D hardness 52, and the Rockwell R hardness 100 corresponds to the shore D hardness 92.

In the prior art, when the tip tip is attached to the distal end of the inner sheath 21, the tip tip does not consider the dilation function for expanding the puncture hole, so that the insertion resistance and the followability to the cavity are taken into consideration. Therefore, a relatively soft material that can obtain sufficient flexibility, for example, PEBAX3533 (Shore D hardness 33) manufactured by Arkema, is used, but such a tip has a poor hardness. Sufficient and difficult to insert into an undilated puncture hole.

Assuming that a guide wire 4 having a diameter of 0.035 inches (≈0.889 mm) is used, the outer diameter at a position 1 mm from the distal end of the tip portion 61 of the dilator portion 6 is a diameter of 1. It is preferably 0.7 mm or less, more preferably 1.5 mm or less in diameter, and most preferably 1.2 mm or less in diameter. The inner diameter at a position 1 mm from the distal end of the tip portion 61 of the dilator portion 6 is preferably 0.89 mm or more in diameter and 1.0 mm or less in diameter, and further preferably 0.95 mm or less in diameter. Most preferably, the diameter is 0.90 mm or less. The wall thickness at a position 1 mm from the distal end of the tip portion 61 of the dilator portion 6 is preferably set to 0.35 mm or less, more preferably 0.25 mm or less, and more preferably 0.15 mm or less. Most preferred.

Assuming that a guide wire 4 having a diameter of 0.025 inches (≈0.635 mm) is used, the outer diameter of the dilator portion 6 at a position 1 mm from the distal end of the tip portion 61 is the diameter. It is preferably 1.6 mm or less, more preferably 1.3 mm or less in diameter, and most preferably 1.0 mm or less in diameter. The inner diameter at a position 1 mm from the distal end of the tip portion 61 of the dilator portion 6 is preferably 0.64 mm or more in diameter, 0.90 mm or less in diameter, and further preferably 0.80 mm or less in diameter. Most preferably, the diameter is 0.70 mm or less. The wall thickness at a position 1 mm from the distal end of the tip portion 61 of the dilator portion 6 is preferably set to 0.35 mm or less, more preferably 0.25 mm or less, and more preferably 0.15 mm or less. Most preferred.

In the present embodiment, the outer diameter of the dilator portion 6 at a position 1 mm from the distal end of the tip portion 61 is 1.20 mm in diameter, the inner diameter is 0.90 mm, and the wall thickness is 0.15 mm. Further, in the present embodiment, Novatec EG6D is used as a material which is easy to mold the dilator portion 6 having such dimensions and has sufficient hardness.

Next, a procedure for placing a stent using the stent delivery device of the present embodiment will be described with reference to FIGS. 3 to 10. For example, when a stent is placed in the abdominal cavity so as to bypass the stomach and the intrahepatic bile duct, it is punctured with a puncture needle 73 so as to reach the bile duct wall 72 from the stomach wall 71 through the abdominal cavity 75 as shown in FIG. Then, as shown in FIG. 4, a puncture hole 74 is formed in both the stomach and the intrahepatic bile duct. After that, as shown in FIG. 5, a guide wire 4 is inserted into each puncture hole 74 to secure a path.

Next, the release lever 32 of the operation unit 3 was moved to the distal end of the groove, and the outer sheath 22 was slid toward the distal end side without expanding the puncture hole 74 by the dilator, that is, FIG. As shown in the above, the distal end portion of the catheter portion 2 (the distal end portion of the catheter portion 2) while the stent 5 arranged in the stent arrangement portion of the inner sheath 21 is held inside the distal end portion of the outer sheath 22 in a reduced diameter state. The tip portion 61) of the dilator portion 6 is inserted into the puncture hole 74 on the stomach wall 71 side. Since the outer diameter of the tip portion 61 of the dilator portion 6 is sufficiently small and hard, it can be easily inserted while expanding the puncture hole 74 on the stomach wall 71 side.

Next, as shown in FIG. 7, when the catheter portion 2 is inserted so that the dilator portion 6 passes through the puncture hole 74 on the stomach wall 71 side and is inserted deeper into the abdominal cavity 75, the puncture hole 74 on the stomach wall 71 side is inserted. Is gradually expanded by the tapered portion 63 of the dilator portion 6, and the puncture hole 74 on the stomach wall 71 side is expanded by the dilator portion 6 to the extent that the distal end portion of the catheter portion 2 (outer sheath 22) can be inserted. After that, the catheter portion 2 (outer sheath 22) is further inserted, and the distal end portion (tip portion 61 of the dilator portion 6) of the catheter portion 2 is inserted into the puncture hole 74 on the bile duct wall 72 side. Since the outer diameter of the tip portion 61 of the dilator portion 6 is sufficiently small and hard, the puncture hole 74 on the bile duct wall 72 side can be easily inserted while being expanded, as in the case of the puncture hole 74 on the stomach wall 71 side. Can be done.

When the catheter portion 2 (outer sheath 22) is further inserted, the puncture hole 74 on the bile duct wall 72 side is gradually expanded by the tapered portion 63 of the dilator portion 6, and the puncture hole 74 on the bile duct wall 72 side is gradually expanded by the dilator portion 6. The distal end of the catheter portion 2 (outer sheath 22) is expanded to the extent that it can be inserted. The catheter portion 2 (outer sheath 22) was further inserted so that the distal end of the stent 5 was located inside the bile duct wall 72 and the proximal end of the stent 5 was located inside the stomach wall 71, as shown in FIG. In this state, the insertion of the catheter portion 6 is stopped.

After that, in the operation unit 3, the release lever 32 is moved toward the proximal end side of the groove, and the outer sheath 22 is slid toward the proximal end side with respect to the inner sheath 21 as shown in FIG. As the outer sheath 22 slides toward the proximal end, the stent 5 is gradually exposed and expanded in diameter from its distal end, and the release lever 32 is moved to the proximal end of the groove, as shown in FIG. In addition, the stent 5 is exposed and expanded in diameter as a whole. After that, the catheter portion 2 and the dilator portion 6 are passed through the inside of the enlarged stent 5 and pulled out to complete the placement of the stent 5.

Since the stent delivery device 1 of the present embodiment is provided with the dilator portion 6 having a dilation function at the distal end of the catheter portion 2 (inner sheath 21), the puncture hole is punctured by the puncture needle and is not expanded. Since it is not necessary to expand the puncture hole separately by using a dilator, it is possible to omit the work of inserting the dilator via the treatment tool guide tube of the endoscope, expanding the puncture hole, and then removing the puncture hole. It is possible to reduce the work man-hours and the work time. Further, since the distal end of the catheter portion 2 (outer sheath 22) can be inserted into the puncture hole while the puncture hole is expanded by the dilator portion 6, expansion and insertion can be performed substantially at the same time, and bile and the like can be collected in the abdominal cavity 75. It is also possible to suppress leakage to the inside.

Next, as another embodiment of the present invention, a modified configuration of the dilator section will be described with reference to FIG. The dilator portion 8 has a tip portion 81 having an outer diameter that can be inserted into an unexpanded puncture hole, a proximal end portion 82 attached to the distal end of the inner sheath 21, and when inserted into the puncture hole. It has a tapered portion 83 that expands the puncture hole to such an extent that the distal end of the outer sheath 22 can be inserted. Further, the dilator portion 8 has a lumen 8a communicating with the lumen of the inner sheath 21, and a guide wire 4 inserted into the inner sheath 21 is inserted into the lumen 8a.

The base end portion 82 has a base end straight body portion 82a having an outer diameter substantially the same as the outer diameter of the outer sheath 22, and a small diameter portion 82b that is insertably inserted into the distal end portion of the lumen of the outer sheath 22. And have. The small diameter portion 82b is formed in a tapered shape so as to become thinner toward the proximal end, and when the outer sheath 22 is slid toward the distal end side with respect to the inner sheath 21, the lumen of the outer sheath 22 is formed. To facilitate insertion into the distal end of the.

The distal end of the inner sheath 21 is connected and fixed to the proximal end of the small diameter portion 82b. The proximal end of the tapered portion 82 is integrally connected to the distal end of the proximal straight body portion 82a. The tapered portion 82 is formed in a tapered shape so as to become thinner toward the distal end, and the proximal end of the tip portion 81 is integrally connected to the distal end of the tapered portion 82. In the present embodiment, the outer shape of the tip portion 81 is formed in a straight body shape so as to have substantially the same outer diameter over the entire length thereof, and the distal end of the tip portion 81 is on the distal end side of the lumen 8a. It has reached the opening.

The dimensions of each part of the dilator portion 8 are, for example, that the length Lb1 of the straight-body tip portion 81 in the central axis direction is in the range of 1 to 3 mm, and the length Lb2 of the base end portion 82 in the central axis direction is 1 to 5 mm. In the range of, the length Lb3 of the tapered portion 83 in the central axis direction is set in the range of 2 to 10 mm, and the outer diameter of the proximal straight body portion 82a is set in the range of 2 to 4 mm. In the present embodiment, the length Lb1 is 2 mm, the length Lb2 is 3 mm, the length Lb3 is 6 mm, and the outer diameter of the base end straight body portion 82a is 2.5 mm. The diameter of the tip portion 81 is 1.20 mm, the inner diameter of the tip portion 81 is 0.90 mm, and the wall thickness of the tip portion 81 is 0.15 mm. Further, in the present embodiment, Novatec EG6D is used as a material which is easy to mold the dilator portion 6 having such dimensions and has sufficient hardness.

The configuration (hardness, forming material, etc.) of the dilator portion 8 other than the above is the same as that of the dilator portion 6 shown in FIG. 2, and the description thereof will be omitted.

Next, as still another embodiment of the present invention, a modified configuration of the dilator section will be described with reference to FIG. The dilator portion 9 was inserted into a tip portion 91 having an outer diameter that can be inserted into an unexpanded puncture hole, a base end portion 92 arranged on the proximal end side opposite to the tip portion 91, and the puncture hole. Occasionally, it has a tapered portion 93 that expands the puncture hole to such an extent that the distal end of the outer sheath 22 can be inserted. Further, the dilator portion 9 has a lumen 9a, a distal end portion of the inner sheath 21 is inserted into the lumen 9a, and the distal end portion of the inner sheath 21 penetrates the dilator portion 9. , Slightly protruding toward the distal end side, and in this state, the dilator portion 9 is fixed to the inner sheath 21.

The base end portion 92 includes a straight body portion 92a having an outer diameter substantially the same as the outer diameter of the outer sheath 22, and a small diameter portion 92b that is insertably inserted into the distal end portion of the lumen of the outer sheath 22. Have. The small diameter portion 92b is formed in a tapered shape so as to become thinner toward the proximal end, and when the outer sheath 22 is slid toward the distal end side with respect to the inner sheath 21, the inner sheath 22 is inside the outer sheath 22. It is designed for easy insertion into the distal end of the cavity.

The proximal end of the tapered portion 92 is integrally connected to the distal end of the straight body portion 92a. The tapered portion 92 is formed so as to become thinner toward the distal end, and the proximal end of the tip portion 91 is integrally connected to the distal end of the tapered portion 92. In the present embodiment, the outer shape of the tip portion 91 is formed in a tapered shape so as to become thinner toward the distal end side thereof, and the distal end of the tip portion 91 is an opening on the distal end side of the lumen 9a. Has reached.

The dimensions of each part of the dilator portion 9 are, for example, that the length Lc1 of the tip portion 91 in the central axis direction is in the range of 1 to 2 mm, and the length Lc2 of the base end portion 92 in the central axis direction is in the range of 1 to 10 mm. The length Lc3 of the tapered portion 93 in the central axis direction is in the range of 2 to 5 mm, the outer diameter of the straight body portion 92a is in the range of 2 to 4 mm, and the protruding length from the distal end of the dilator portion 9 of the inner sheath 21. Lc4 is set in the range of 0.5 to 15 mm. In the present embodiment, the length Lc1 is 1 mm, the length Lc2 is 6 mm, the length Lc3 is 3 mm, the outer diameter of the straight body portion 92a is 2.5 mm, and the length Lc4 is 2 mm.

The configuration (hardness, forming material, etc.) of the dilator portion 9 other than the above is the same as that of the dilator portion 6 shown in FIG. 2, and the description thereof will be omitted.

The embodiments described above are described for facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above-described embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

1 ... Stent delivery device 2 ... Catheter part 21 ... Inner sheath 22 ... Outer sheath 3 ... Operation part 31 ... Release handle 32 ... Release lever 4 ... Guide wire 5 ... Stent 6 ... Dilator part 61 ... Tip part 62 ... Base end part 63 ... Tapered portion 71 ... Stomach wall 72 ... Bile duct wall 73 ... Puncture needle 74 ... Puncture hole 75 ... Abdominal cavity

Claims (1)

A stent delivery device in which a self-expanding stent is placed in a hole to be expanded, which is a puncture hole in the wall of a luminal organ punctured by a puncture needle.
An inner sheath having a stent placement portion for placing the stent on the outer peripheral surface near the distal end thereof and the inner sheath are slidably inserted, and the stent placed in the stent placement portion is contracted. A catheter part having an outer sheath that holds it in a diameterd state,
It consists of a substantially cylindrical member having a single lumen attached to the distal end of the inner sheath, and is inserted into the dilated hole and the tip having an outer diameter that can be inserted into the dilated hole. At that time, the dilator portion having a tapered portion that expands the expanded hole to the extent that the distal end portion of the outer sheath can be inserted is provided.
The proximal end of the tip is integrally connected to the distal end of the taper.
The tip portion is formed of a material having a straight body shape having a length in the central axis direction of 1 to 3 mm, a shore D hardness of 70 or more, and a hardness of 70 or more.
The stent delivery device is characterized in that the tapered portion has a tapered shape that becomes thinner toward the distal end and has a length in the central axis direction of 2 to 10 mm.

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