JP6904385B2 - 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). 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, a puncture needle is used to puncture the stomach wall through the abdominal cavity to the intrahepatic bile duct, and a guide wire is inserted to secure a route, and the stomach wall and the bile duct wall (liver). ) Is expanded with a dilator or the like to the extent that the distal end of the catheter can be inserted, and then the distal end of the catheter (stent placement) is bridged between the gastric wall puncture hole and the bile duct wall puncture hole. The stent is placed in the puncture hole of the stomach wall and the bile duct wall by pulling out the outer sheath in this state and releasing (exposing / expanding the diameter) the stent.

Japanese Unexamined Patent Publication No. 2012-139471

However, when the distal end of the catheter (stent placement) is inserted into the puncture hole of the stomach wall, the stomach wall is in close contact with the outer periphery of the outer sheath, and the stent is released (diagnosed) in order to release the stent. When the outer sheath is slid in the pulling direction, the close contact portion of the stomach wall is guided (pulled) inward following the outer sheath by friction or the like, and when the diameter of the stent is expanded in this state, the distal end of the stent is reached. Only the part (the end on the liver side) is placed in the puncture hole of the bile duct wall, and the proximal end of the stent (the end on the stomach side) is not placed in the puncture hole of the stomach wall, but on the proximal side of the stent. There is a problem that the opening may be located in the abdominal cavity. If left in place in such an inappropriate state, bile and gastric contents may leak into the abdominal cavity, and the procedure must be redone.

The present invention has been made in view of these points, and is a stent delivery device capable of indwelling a stent in an appropriate state when bypassing between luminal organs by using a self-expanding stent. The purpose is to provide.

The stent delivery device according to the present invention
A stent delivery device that places a self-expanding stent in a puncture hole formed in the wall of a luminal organ.
An inner sheath having a stent placement portion for placing the stent on the outer peripheral surface near the distal end thereof,
An outer sheath in which the inner sheath is slidably inserted and the stent placed in the stent placement portion is held in a reduced diameter state, and an outer sheath.
When the outer sheath is slidably inserted and the outer sheath is slid toward the proximal end side with respect to the inner sheath to pull out the distal end portion of the outer sheath from the puncture hole, the puncture hole It is characterized by comprising a stopper tube having a holding portion at its distal end that abuts at least a portion of the surrounding luminal organ wall.

The stent delivery device according to the present invention further has an operating portion to which the proximal end of the inner sheath is attached and the proximal end of the outer sheath is slidably attached.
A position adjusting means for leasably fixing the proximal end of the stopper tube to the operating portion can be provided.

In the stent delivery device according to the present invention, the holding portion is formed by cutting out the distal end portion of the stopper tube so that the cross section orthogonal to the central axis thereof is a semicircle or an arc shape less than a semicircle. Can be used.

In the stent delivery device according to the present invention, as the holding portion, at least one protrusion that elastically deforms outward as the diameter of the stent expands is provided at the distal end portion of the stopper tube. Can be done.

In the stent delivery device according to the present invention, as the holding portion, a large-diameter portion having an inner diameter larger than the diameter of the expanded diameter of the stent is provided at the distal end portion of the stopper tube. Can be done. In this case, the large diameter portion may have a slit in a direction along its central axis from its distal end.

According to the stent delivery device of the present invention, when the outer sheath is slid toward the proximal end side with respect to the inner sheath in the puncture hole formed in the wall of the luminal organ to release (increase) the stent. Since the holding portion of the stopper tube abuts on at least a part of the wall of the luminal organ around the puncture hole, it moves toward the proximal end side of the wall of the luminal organ as the outer sheath slides toward the proximal end side. The change in position can be reduced. Therefore, the stent can be placed in an appropriate position.

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 partial cross-sectional view which shows the structure of the distal end part of the stent delivery apparatus of embodiment of this invention. It is a perspective view which shows the structure of the distal end part of the stopper tube of the stent delivery device of embodiment of this invention. It is a side view which shows an example of the stent applied to the stent delivery apparatus of embodiment of this invention. It is a partial cross-sectional view which shows the structure of the operation part of the stent delivery apparatus of embodiment of this invention. It is a top view which shows the structure of the operation part of the stent delivery apparatus of embodiment of this invention. It is a figure which shows the operation (catheter part 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 operation (during the release of a stent) 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 operation (the release completion of a stent) 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 operation (catheter part insertion) at the time of placing a stent in a puncture hole using a conventional stent delivery device. It is a figure which shows the operation (during the release of a stent) when a stent is placed in a puncture hole using a conventional stent delivery device. It is a figure which shows the operation (the release completion of a stent) at the time of placing a stent in a puncture hole using a conventional stent delivery device. It is a side surface which shows the modification of the stopper tube of the stent delivery apparatus of embodiment of this invention. It is a side view which shows the other modification of the stopper tube of the stent delivery apparatus of embodiment of this invention. It is a side view which shows the further modification of the stopper tube of the stent delivery device of embodiment of this invention.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In this 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.

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, and a stent 5 as an indwelling target. The vicinity of the distal end of the catheter portion 2 including the stent 5 may be curved in a curved state depending on the shape of the site to be placed, but in the present embodiment, the vicinity of the distal end is not curled and is linear. The catheter portion 2 is used.

The catheter portion 2 has an inner sheath (inner tube) 21 having a distal end and a proximal end, an outer sheath (outer tube) 22 having a distal end and a proximal end, and a distal end and a proximal end. It is provided with a stopper tube 23.

Contrast-enhanced markers (not shown) are attached in the vicinity of the distal ends of the inner sheath 21, the outer sheath 22, and the stopper tube 23, 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 therein. 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 4.0 mm.

A tip tip 24 formed so as to become thinner toward the tip (distal end) of the inner sheath 21 is attached to the distal end of the inner sheath 21. The tip tip 24 has an opening 24a that communicates with the distal end of the lumen of the inner sheath 21 along its central axis, and its proximal end is the distal end of the lumen of the outer sheath 22. It is a small diameter portion 24b having an outer diameter that can be inserted into the portion (see FIGS. 2 and 3). The tip tip 24 plays a role of reducing the insertion resistance of the catheter portion 2 and facilitating insertion into the body, and is made of polyamide, polyamide elastomer, polyurethane, fluororesin such as polytetrafluoroethylene, polyethylene and the like. It can be formed from a polyolefin resin or the like.

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. 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 4.5 mm, and the outer diameter is about 1.0 to 5.0 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 copolymers, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides, and polyether polyamides. , Polyester polyamide, polyether ether ketone, polyetherimide, polytetrafluoroethylene and various resin materials such as fluororesins such as 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.

The stopper tube 23 is made of a flexible elongated tube and has a cavity into which the outer sheath 22 is slidably inserted. As the stopper tube 23, a tube having an inner diameter larger than the outer diameter of the outer sheath 22 by 0.05 to 1.0 mm and having a wall thickness in the range of 0.1 to 1.0 mm can be used. As the material of the stopper tube 23, polyacetal, polytetrafluoroethylene, tetrafluoroethylene / hexafluoropropylene copolymer, synthetic resin such as polypropylene, metal such as stainless steel, and the like can be used. The stopper tube 23 can slide (relatively move) in the axial direction with respect to the outer sheath 22 by operating the operation unit 3.

The stopper tube 23 slides the outer sheath 22 toward the proximal end side with respect to the inner sheath 21 in the puncture hole formed in the luminal organ wall (in this embodiment, the stomach wall) at the distal end thereof. The stent 5 has a holding portion that abuts at least a part of the wall of the luminal organ around the puncture hole when the stent 5 is released (diameter expanded).

When the stent 5 is released (expanded in diameter), the shape and structure of the holding portion abuts on at least a part of the luminal organ wall around the puncture hole, and the luminal organ wall is on the proximal end side. As long as it can be suppressed from being pulled by the stent 5 and does not hinder the release of the stent 5, it is not particularly limited, but in the present embodiment, as shown in FIGS. 2 to 4, the distal end portion of the stopper tube 23 Is cut out so that the cross section substantially orthogonal to the central axis is semicircular, and the notch portion 23b is formed, and the remaining half-divided cylindrical portion is used as the pressing portion 23a. The length of the notch 23b along the axial direction of the stopper tube 23 should be such that the stopper tube 23 does not interfere with the release of the stent 5 when the pressing portion 23a abuts on the wall of the luminal organ around the puncture hole. For example, it may be set in the range of 3 to 50 mm. The pressing portion 23a may have a shape cut out from the distal end portion of the stopper tube 23 so that the cross section substantially orthogonal to the central axis thereof has an arc shape of less than a semicircle.

The stent 5 is a self-expandable covered stent that expands in diameter from a contracted state by its own elastic force. As shown in FIG. 5, a tubular bare stent 51 formed by a frame and an outer circumference of the bare stent 51 are covered. It has a covering film portion 52 to cover. The bare stent 51 is made of a superelastic metal such as a nickel titanium alloy or a cobalt chrome alloy, a shape memory metal, or the like. The surface of the bare stent 51 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 51 covered with the coating film is covered with a coating film portion 52 such as a polymer film. There is.

The total length of the stent 5 is determined according to the distance between the luminal organs to be bypass-connected, 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 bypass-connected. It is determined according to the bypass, etc., but 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.

Returning to FIG. 1, the guide wire 4 is inserted into the lumen of the inner sheath 21, and its distal end protrudes from the opening 24a (see FIGS. 2 and 3) of the distal end of the tip 24 of the inner sheath 21. At the same time, the proximal end thereof is arranged so as to be exposed to the outside through the opening 21a of the proximal end of the inner sheath 21 arranged so as to penetrate the operation portion 3.

As shown in FIGS. 6 and 7, 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 has a through hole in the central portion thereof. The distal end side lid member 31a is closed by being integrally attached, and the proximal end side opening is integrally attached by the proximal end side lid member 31b having a through hole in the central portion thereof. It is blocked.

The proximal end of the outer sheath 22 is slidably inserted into the through hole of the distal end side lid member 31a of the release handle 31, and the proximal end of the outer sheath 22 is located inside the release handle 31. .. A groove 33 is formed on the side wall of the release handle 31 so as to penetrate inward and outward in the direction along the central axis thereof. The foot portion 32a of the release lever 32 having the head portion located outside the release handle 31 and the foot portion 32a erected in the central portion of the head portion is arranged through the groove 33.

The tip (lower end) of the foot 32a 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 33. As a result, 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 31b). ..

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 31b of the release handle 31, and the proximal end thereof is released. It is located outside the handle 31. The inner sheath 21 is fixed to the proximal end side lid member 31b at the portion of the through hole.

When the release lever 32 is moved to the distal end of the groove 33, the distal end of the outer sheath 22 reaches the tip tip 24 and is far from the lumen of the outer sheath 22, as shown in FIGS. 2 and 3. A small diameter portion 24b of the tip tip 24 is interpolated at the distal end portion, and in this state, the stent 5 arranged in the stent arrangement portion of the inner sheath 21 is held inside the stent 5 in a reduced diameter state. It has become. When the release lever 32 is moved to the proximal end side of the groove 33 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 distal to the outer sheath 22. It is pushed out relative to the edge and the stent 5 is released (diameter expanded) by a self-expanding force.

The proximal end of the stopper tube 23 into which the outer sheath 22 is inserted is located outside the protruding tubular portion 35 provided so as to project toward the distal end side from the distal end side lid member 31a of the release handle 31. ing. The protruding cylinder portion 35 has an inner diameter through which the outer sheath 22 can be inserted and an outer diameter such that the outer peripheral side thereof can be covered with the stopper tube 23. A position adjusting stopper (position adjusting means) 28 is fixed to the proximal end of the stopper tube 23. The position adjusting stopper 28 is for fixing the stopper tube 23 to the protruding cylinder portion 35 of the release handle 31 so as to be releasable. In the present embodiment, the position adjusting stopper 28 has a screw member 28a, and when the screw member 28a is screwed, a screw is screwed. By engaging the member 28a with the protruding cylinder portion 35, the stopper tube 23 can be fixed to the release handle 31 without hindering the sliding of the outer sheath 22. On the other hand, by loosening the screw member 28a, the engagement of the screw member 28a with the release handle 31 is released, and the relative position of the stopper tube 23 with respect to the release handle 31 can be adjusted.

By moving the position adjusting stopper 28 (screw member 28a) to the distal end side or the proximal end side of the protruding tubular portion 35 of the release handle 31, the range of the axial length of the protruding tubular portion 35 Within, the position of the distal end of the retainer 23a with respect to the stent 5 can be adjusted. The length of the protruding cylinder portion 35 in the axial direction may be set in the range of, for example, 5 to 50 mm.

Next, a procedure for placing a stent using the stent delivery device of the present embodiment will be described with reference to FIGS. 8 to 10. For example, when a stent is placed in the abdominal cavity so as to bypass the stomach and the intrahepatic bile duct via an endoscopic treatment tool guide tube inserted into the stomach, the stomach wall 61 is as shown in FIG. After puncturing with a puncture needle from the abdominal cavity 63 to the bile duct wall 62, inserting a guide wire to secure a path, and expanding the puncture holes of the stomach wall 61 and the bile duct wall 62 with a dilator or the like as necessary. The distal end of the catheter portion 2 is inserted into the puncture hole. In this operation, in the operation unit 3 shown in FIGS. 6 and 7, the release lever 32 is moved to the distal end of the groove 33 so that the distal end of the outer sheath 22 reaches the tip tip 24. A state in which the outer sheath 22 is slid toward the distal end side, that is, a state in which 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. It is done in.

Next, in the operation unit 3 shown in FIGS. 6 and 7, the stopper tube 23 is appropriately slid in a state where the screw member 28a of the position adjusting stopper 28 is loosened, and the stopper tube 23 is pressed as shown in FIG. With the distal end of the portion 23a positioned so as to abut against the stomach wall 61 around the puncture hole, the screw member 28a is tightened to fix the stopper tube 23 to the release handle 31.

Next, in the operation unit 3 shown in FIGS. 6 and 7, the release lever 32 is moved to the proximal end side of the groove 33, and as shown in FIG. 9, the outer sheath 22 is proximal to the inner sheath 21. Slide to the side. As the outer sheath 22 slides, the stent 5 is gradually exposed and expanded in diameter from its distal end side, and by moving the release lever 32 to the proximal end of the groove 33, the stent 5 is as shown in FIG. Is exposed and expanded in diameter as a whole. Then, the distal end of the catheter portion 2 is passed through the inside of the enlarged stent 5 and pulled out to complete the placement of the stent 5.

Here, for comparison with the present embodiment, the case where the stent is placed by using the conventional stent delivery device not provided with the stopper tube 23 as in the present embodiment is simplified with reference to FIGS. 11 to 13. Explain to. As shown in FIG. 11, from the state in which the distal end of the catheter portion 2 is inserted from the puncture hole of the stomach wall 61 through the abdominal cavity 63 to the puncture hole of the bile duct wall 62, the outer sheath is as shown in FIG. When 22 is pulled out, the stomach wall 61 around the puncture hole is dragged by the frictional force and pulled toward the proximal end side as the outer sheath 22 is pulled out, and when the outer sheath 22 is completely pulled out, FIG. 13 shows. As shown, when the proximal end of the stent 5 is disengaged from the puncture hole of the stomach wall 61 and the diameter is expanded in the abdominal cavity 63, and the opening on the proximal end side of the stent 5 is placed in the abdominal cavity 63. If the patient is placed in such an inappropriate state, the bile and gastric contents may leak into the abdominal cavity 63, and the procedure must be repeated.

On the other hand, in the stent delivery device 1 of the present embodiment, as shown in FIGS. 8 to 10, the outer sheath 22 is slid toward the proximal end side to release the stent 5, and the outer sheath 22 is slid from the inside of the puncture hole. When pulling out, the distal end of the holding portion 23a of the stopper tube 23 is in contact with the stomach wall 61 around the puncture hole, so that the stomach wall 61 around the puncture hole is dragged by the pulling out of the outer sheath 22. It is prevented from being pulled toward the proximal end side. Therefore, the stent 5 can be placed in an appropriate position.

Further, the stopper tube 23 of the present embodiment is cut out at the distal end portion so that the cross section substantially orthogonal to the central axis thereof is semicircular to form a notch portion 23b, and the remaining half-split cylindrical shape is formed. Since the portion is a pressing portion 23a and the inside of the pressing portion 23a is opened as a notch portion 23b, there is little obstacle when the stent 5 expands in diameter.

Next, a modified example of the holding portion at the distal end of the stopper tube will be described with reference to FIGS. 14 to 16. In the modified example shown in FIG. 14, the holding portion has a tubular portion having an inner diameter and an outer diameter larger than that of the stopper tube 23 arranged at the distal end portion of the stopper tube 23, and the distal end thereof is arranged in the tubular portion. A pair of slits 231b are formed from the side along the central axis thereof, and the remaining portion (a pair of protrusions) is used as a pressing portion 231a.

Here, the slits 231b are formed at positions facing each other 180 degrees, and therefore, two pressing portions 231a having a substantially arcuate cross section are provided. The pressing portion 231a is configured to elastically deform outward, and when the stent 5 is expanded in diameter, it elastically deforms outward due to the pressing force at this time, and does not hinder the expansion of the diameter of the stent 5. I am trying to do it.

When the outer sheath 22 is pulled out from the puncture hole, the distal end of the holding portion 231a of the stopper tube 23 abuts at two points so as to surround the stomach wall around the puncture hole. The stomach wall around the puncture hole is prevented from being dragged by it and pulled towards the proximal end.

In this modification, the tubular portion has a diameter larger than that of the stopper tube 23, but the holding portion is formed by forming a plurality of slits in the tubular portion having the same diameter as the stopper tube 23. May be configured. Further, the number of slits 231b may be two or more, and three or more pressing portions 231a may be formed. Further, although the pressing portion 231a is arranged substantially parallel to the central axis thereof, the pressing portion 231a may be plastically deformed so as to open outward so as to be in a pre-opened state. Further, the distal end portion of the pressing portion 231a may be curled outward.

In the modified example shown in FIG. 15, the holding portion has a tubular portion having an inner diameter and an outer diameter larger than that of the stopper tube 23 arranged at the distal end portion of the stopper tube 23, and the distal end thereof is arranged in the tubular portion. A pair of slits 232b are formed from the side along the central axis thereof, and the remaining portion (a pair of protrusions) is used as a pressing portion 232a. In this modified example, the tubular portion at the distal end of the stopper tube 23 is set to have a larger diameter than the tubular portion of the modified example shown in FIG. 14, and is set to a value larger than the diameter when the stent 5 is released. doing.

Here, the slits 232b are formed at positions facing each other by 180 degrees, and therefore, two pressing portions 232a having a substantially arcuate cross section are provided. Further, since the inner diameter of the holding portion 232a of this modified example is larger than the outer diameter when the diameter of the stent 5 is expanded, it does not hinder the expansion of the diameter of the stent 5 as it is, so that it is not necessarily elastically deformed. No need to configure.

When the outer sheath 22 is pulled out from the puncture hole, the distal end of the holding portion 232a of the stopper tube 23 abuts at two points so as to surround the tissue around the puncture hole of the stomach in a relatively wide range. As the outer sheath 22 is pulled out, the tissue around the puncture hole of the stomach is prevented from being dragged by the outer sheath 22 and pulled toward the proximal end side.

The number of slits 232b may be two or more, and three or more holding portions 232a may be formed. However, in this modified example, unlike the modified example of FIG. 14, the holding portion does not need to be elastically deformed to the outside, so that the number of slits 232b may be one or the slits 232b may not be provided at all. The slit 232b serves as a window for visually observing the stent 5 housed in the outer sheath 22.

In still another modification shown in FIG. 16, a spiral coil spring is provided at the distal end of the stopper tube 23, and this coil spring is used as a pressing portion 233. The diameter of the coil spring 233 gradually increases from the distal end of the stopper tube 23, and the distal end side is configured to have an inner diameter larger than the diameter when the stent 5 is released. When the diameter of the stent 5 is expanded, the urging force of the coil spring 233 can hold down a relatively wide area around the puncture hole as a whole without obstructing the diameter of the stent 5. A single or a plurality of beam members may be fixed to regulate the expansion and contraction of the coil spring 233 in the direction along the central axis thereof.

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 23 ... Stopper tube 23a, 231a, 232a, 233 ... Holding part 28 ... Position adjustment stopper 28a ... Screw member 24 ... Tip tip 3 ... Operation part 31 ... Release handle 32 ... Release lever 33 ... Groove 35 ... Protruding cylinder 4 ... Guide wire 5 ... Stent 61 ... Stomach wall 62 ... Bile duct wall 63 ... Abdominal cavity

Claims (5)

A stent delivery device that places a self-expanding stent in a puncture hole formed in the wall of a luminal organ.
An inner sheath having a stent placement portion for placing the stent on the outer peripheral surface near the distal end thereof,
An outer sheath in which the inner sheath is slidably inserted and the stent placed in the stent placement portion is held in a reduced diameter state, and an outer sheath.
When the outer sheath is slidably inserted and the outer sheath is slid toward the proximal end side with respect to the inner sheath and the distal end portion of the outer sheath is pulled out from the puncture hole, the puncture hole is opened. a stopper tube having a pressing portion to prevent at least partly around the hollow organ wall and abutting the proximal end side tube organ wall is pulled near end side at a distal end thereof A stent delivery device comprising. The holding portion according to claim 1, wherein the holding portion is cut out from the distal end portion of the stopper tube so that the cross section orthogonal to the central axis thereof is a semicircle or an arc shape less than a semicircle. Stent delivery device. The stent delivery according to claim 1, wherein the holding portion is provided at a distal end portion of the stopper tube with at least one protrusion portion that elastically deforms outward as the diameter of the stent increases. apparatus. The stent delivery according to claim 1, wherein the holding portion is provided with a large diameter portion having an inner diameter larger than the diameter of the stent in an expanded state at the distal end portion of the stopper tube. apparatus. The stent delivery device according to claim 4, wherein the large-diameter portion has a slit extending from the distal end of the large-diameter portion along the central axis of the large-diameter portion.

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