JP2019171224A - Stent delivery device - Google Patents

Abstract

To enable a stent to be placed in an appropriate state.SOLUTION: A stent delivery device for placing a self-expanding type stent 5 in a puncture hole formed on a lumen organ wall (gastric wall 61) includes: an inner sheath 21 having a stent arrangement part for arranging the stent on an outer peripheral surface in the vicinity of the distal end; an outer sheath 22 into which the inner sheath is slidably inserted for holding the stent arranged in the stent arrangement part in a diameter-contracted state; and a stopper tube 23 into which the outer sheath is slidably inserted, which includes a pressing part 23a that abuts against at least part of the gastric wall 61 around the puncture hole when pulling a distal end part of the outer sheath out of the puncture hole at the distal end part.SELECTED DRAWING: Figure 10

Description

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

  In recent years, cases of unresectable malignant biliary strictures or obstructions that require biliary drainage, where transduodenal papilla approach is not possible, etc., and ultrasound-guided transduodenal (or transgastric) There are some reports of hepatic biliary drainage (EUS-BD). EUS-BD inserts an ultrasound endoscope into the duodenum (or stomach) and punctures the common bile duct (or intrahepatic bile duct) with a puncture needle from the duodenum (or stomach) wall while observing ultrasound images in real time. Then, after inserting a guide wire into the bile duct through this puncture hole, a bypass tube connecting the inside of the duodenum (or stomach) and the common bile duct (or intrahepatic bile duct) is inserted and placed along the guide wire. It is a procedure. This procedure enables biliary drainage by embedding a bypass tube in the body.

  As a bypass tube used for such an EUS-BD, a self-expanding stent provided with a coating film may be used. As a stent delivery device used in this case, for example, as described in Patent Document 1 below, a catheter portion having an inner sheath and an outer sheath through which the inner sheath is slidably inserted is provided. A stent is placed in a stent placement portion provided near the distal end of the sheath, and the stent is held in a state where the diameter of the stent is reduced inside the vicinity of the distal end of the outer sheath. Is known to expand the diameter of the stent by sliding the outer sheath with respect to the inner sheath.

  For example, when bypassing the stomach and the intrahepatic bile duct, puncture with a puncture needle from the stomach wall through the abdominal cavity to the intrahepatic bile duct, a guide wire is inserted to secure the path, and the stomach wall and bile duct wall (liver) ) Is expanded with a dilator or the like so that the distal end of the catheter portion can be inserted, and then the distal end portion (stent placement portion) of the catheter portion is bridged between the puncture hole of the stomach wall and the puncture hole of the bile duct wall In this state, the outer sheath is pulled out, and the stent is released (exposed / expanded diameter) to place the stent in the puncture holes of the stomach wall and the bile duct wall.

JP 2012-139471 A

  However, when the distal end portion (stent placement portion) of the catheter portion 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 in order to release (expand the diameter) the stent, When the outer sheath is slid in the pulling direction, the close contact portion of the stomach wall follows the outer sheath due to friction or the like, and is guided (pulled) inward, and when the diameter of the stent expands in this state, the distal end of the stent Only the end of the stent (liver side end) is placed in the puncture hole of the bile duct wall, and the proximal end of the stent (end of the stomach side) is not placed in the puncture hole of the stomach wall. There has been a problem that the opening may be located in the abdominal cavity. If placed in such an inappropriate state, leakage of bile and stomach contents into the abdominal cavity may occur, and the procedure needs to be repeated.

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

The stent delivery device according to the present invention comprises:
A stent delivery device for placing a self-expanding stent in a puncture hole formed in a luminal organ wall,
An inner sheath having a stent placement portion for placing the stent on the outer peripheral surface near the distal end;
An outer sheath that is slidably inserted through the inner sheath and that holds the stent disposed in the stent placement portion in a reduced diameter state; and
The outer sheath is slidably inserted, and when the outer sheath is slid proximally with respect to the inner sheath and the distal end of the outer sheath is pulled out of the puncture hole, And a stopper tube having a pressing portion at a distal end thereof that abuts against at least a part of a surrounding luminal organ wall.

In the stent delivery device according to the present invention, the proximal end of the inner sheath is attached, and the proximal end of the outer sheath is further slidably attached.
Position adjusting means for releasably fixing the proximal end portion of the stopper tube to the operation portion may be provided.

  In the stent delivery device according to the present invention, as the pressing portion, the distal end portion of the stopper tube is cut out so that a cross section perpendicular to the central axis thereof is a semicircle or an arc shape less than a semicircle. Things can be used.

  In the stent delivery device according to the present invention, as the pressing portion, one having a distal end portion of the stopper tube provided with at least one protruding portion that elastically deforms outward as the diameter of the stent expands is used. Can do.

  In the stent delivery device according to the present invention, as the pressing portion, a device in which a distal end portion of the stopper tube is provided with a large-diameter portion having an inner diameter larger than the diameter of the expanded state of the stent is used. Can do. In this case, the large diameter portion may have a slit in a direction along the central axis from the distal end.

  According to the stent delivery device of the present invention, when the outer sheath is slid to the proximal end side with respect to the inner sheath in the puncture hole formed in the lumen organ wall, the stent is released (expanded diameter). Since the holding portion of the stopper tube abuts at least a part of the luminal organ wall around the puncture hole, the squeezing of the outer sheath toward the proximal end side of the luminal organ wall accompanying the sliding toward the proximal end side of the outer sheath 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 section figure 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 apparatus 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 section figure 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 | movement (catheter part insertion) at the time of indwelling a stent in a puncture hole using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the operation | movement (during the release of a stent) 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 operation | movement (stent release completion) at the time of indwelling a stent in a puncture hole using the stent delivery apparatus of embodiment of this invention. It is a figure which shows the operation | movement (catheter part insertion) at the time of indwelling a stent in a puncture hole using the conventional stent delivery apparatus. It is a figure which shows the operation | movement (during the release of a stent) at the time of indwelling a stent in a puncture hole using the conventional stent delivery apparatus. It is a figure which shows the operation | movement (stent release completion) at the time of indwelling a stent in a puncture hole using the conventional stent delivery apparatus. 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 other modification of the stopper tube of the stent delivery apparatus of embodiment of this invention.

  Embodiments of the present invention will be specifically described below with reference to the drawings. In this embodiment, ultrasonic endoscopy-guided transgastric transhepatic biliary drainage (EUS-BD), that is, a bypass tube (self-expanding stent) that bypasses the stomach and intrahepatic bile duct is placed. Will be described as an example. However, the present invention is not limited to the one that bypasses 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 a proximal end side of an elongated catheter part 2 inserted into a patient's body (lumen) and the proximal end side of the catheter part 2 through a treatment instrument guide tube of an endoscope (not shown). An operation unit 3 for operating the catheter unit 2 inside the body from the outside, a guide wire 4 and a stent 5 as an indwelling target are roughly provided. The vicinity of the distal end of the catheter part 2 including the stent 5 may be bent in a curved state depending on the shape of the site to be placed, but in this embodiment, a straight line that is not hooked is used. The catheter part 2 is used.

  The catheter part 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. A stopper tube 23 is provided.

  In the vicinity of the distal ends of the inner sheath 21, outer sheath 22, and stopper tube 23, contrast markers (not shown) are respectively attached. A contrast marker is a marker in the body that is detected by fluoroscopy, and is formed of, for example, a metal material such as gold, platinum, or tungsten, or a polymer blended with barium sulfate or bismuth oxide. .

  The inner sheath 21 is composed of an elongated tube having flexibility, and a guide wire 4 used as a guide for inserting the catheter portion 2 into the patient's body is inserted therein. After the guide wire 4 is inserted into the body to secure a path between the outside of the body and the inside of the body, the catheter portion 2 is pushed (advanced) along the guide wire 4 so that the distal end side of the catheter portion 2 is positioned within 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 disposed) is about 0.5 to 4.0 mm.

  A distal tip 24 is attached to the distal end of the inner sheath 21 so as to become thinner as it goes to the distal end (distal end). The tip 24 has an opening 24 a communicating with the distal end of the lumen of the inner sheath 21 along the central axis, and the proximal end thereof is the distal end of the lumen of the outer sheath 22. The small-diameter portion 24b has an outer diameter that can be inserted into the portion (see FIGS. 2 and 3). The distal tip 24 plays a role of reducing insertion resistance of the catheter part 2 and facilitating insertion into the body, such as polyamide, polyamide elastomer, polyurethane, fluorine resin such as polytetrafluoroethylene, and polyethylene. 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 this fixing ring 25 is for defining the position of the proximal end of the stent 5. The distal end side portion is a stent placement portion. In the stent placement portion, the stent 5 is placed so as to cover the inner sheath 21. Further, another elongate tube (not shown) is coaxially provided on the proximal end side of the fixing ring 25 of the inner sheath 21 so as to cover the elongate tube constituting the inner sheath 21 main body, A portion of the inner sheath 21 closer to the proximal end than the fixing ring 25 is thicker than a portion of the inner sheath 21 closer to the distal end than the fixing ring 25. Thus, the proximal end side portion of the inner sheath 21 is thicker than the fixing ring 25, so that the pushability of the inner sheath 21 is increased and the operability is improved, and the position of the fixing ring 25 is proximal. Shifting to the end side is prevented.

  The outer sheath 22 is made of an elongated tube having flexibility, has an inner diameter slightly larger than the outer diameter of the inner sheath 21, and the inner sheath 21 is slidably inserted into the inner 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 is slidable (relatively moved) in the axial direction with respect to the inner sheath 21 by operating the operation unit 3.

  Examples of the material for the inner sheath 21 and the outer sheath 22 include polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamide, and polyether polyamide. , Polyester polyamide, polyetheretherketone, polyetherimide, various resin materials such as polytetrafluoroethylene and fluororesin such as tetrafluoroethylene / hexafluoropropylene copolymer, polystyrene, polyolefin, polyurethane, polyester It is possible to use various thermoplastic elastomers such as those based on polyamide, polyamide and polybutadiene. Two or more of these can be used in combination.

  The stopper tube 23 is made of an elongated tube having flexibility, and has a lumen into which the outer sheath 22 is slidably inserted. As the stopper tube 23, a tube having an inner diameter 0.05 to 1.0 mm larger than the outer diameter of the outer sheath 22 and having a 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, or the like can be used. The stopper tube 23 can be slid (relatively moved) in the axial direction with respect to the outer sheath 22 by operating the operation unit 3.

  The stopper tube 23 is slid to the proximal end side with respect to the inner sheath 21 within the puncture hole formed in the lumen organ wall (in this embodiment, the stomach wall) at the distal end thereof. When the stent 5 is released (expanded diameter), it has a pressing portion that comes into contact with at least a part of the luminal organ wall around the puncture hole.

  When the stent 5 is released (expanded diameter), the shape and configuration of the pressing portion is in contact with at least a part of the luminal organ wall around the puncture hole so that the luminal organ wall is on the proximal end side. Although it is not particularly limited as long as it can be prevented from being pulled by the tube and does not hinder the release of the stent 5, in this embodiment, as shown in FIGS. 2 to 4, the distal end portion of the stopper tube 23 is used. Is cut out so that the cross section substantially perpendicular to the central axis thereof is semicircular, and a cutout portion 23b is formed, and the remaining half-cylindrical portion is used as a pressing portion 23a. The length of the notch portion 23b along the axial direction of the stopper tube 23 is such that the stopper tube 23 does not interfere with the release of the stent 5 when the pressing portion 23a comes into contact with the luminal organ wall around the puncture hole. What is necessary is just to set in the range of 3-50 mm, for example. In addition, as the holding | suppressing part 23a, it is good also as a shape notched so that the cross section substantially orthogonal to the central axis may become circular arc shape which is less than a semicircle at the distal end part of the stopper tube 23.

  The stent 5 is a self-expanding covered stent that expands from its contracted state by its own elastic force. As shown in FIG. 5, a cylindrical bare stent 51 formed by a frame and an outer periphery of the bare stent 51 And a covering film portion 52 for covering. The bare stent 51 is formed of a superelastic metal such as a nickel titanium alloy or a cobalt chromium alloy, a shape memory metal, or the like. The surface of the bare stent 51 is covered with a coating film spreading so as to fill between adjacent frames, and the outer periphery of the bare stent 51 covered with the coating film is covered with a covering film portion 52 such as a polymer film. Yes.

  The total length of the stent 5 is determined according to the distance between the luminal organs to be bypassed, and is about 30 to 200 mm. The outer diameter at the time of diameter expansion is the type and size of the luminal organ to be bypassed. Although it is determined depending on the size, 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 stent 5 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 24 a (see FIGS. 2 and 3) at the distal end of the tip tip 24 of the inner sheath 21. In addition, the proximal end of the inner sheath 21 is disposed so as to be exposed to the outside through the opening 21 a at the proximal end of the inner sheath 21 disposed through the operation unit 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 at the center 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 at the center 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 in the side wall of the release handle 31 so as to penetrate inward and outward in a direction along the central axis. In the groove 33, the foot 32a of the release lever 32 having a head positioned outside the release handle 31 and a foot 32a erected in the center of the head is disposed.

  The distal end (lower end) of the foot 32 a of the release lever 32 is fixed to the proximal end of the outer sheath 22 located inside the release handle 31, and moves the release lever 32 along the groove 33. Thus, the outer sheath 22 can be slid to 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 portion of the inner sheath 21 inserted through the outer sheath 22 passes through the release handle 31, passes through the through hole of the proximal end side lid member 31b of the release handle 31, and the proximal end 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.

  In a state where 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 as shown in FIGS. The small diameter portion 24b of the distal tip 24 is inserted into the distal end portion, and in this state, the stent 5 disposed in the stent placement portion of the inner sheath 21 is held in its reduced 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 moved to the distal side of the outer sheath 22. The stent 5 is pushed out relatively from the end, and the stent 5 is released (expanded diameter) by the self-expanding force.

  The proximal end of the stopper tube 23 in which the outer sheath 22 is inserted is located outside the protruding cylindrical portion 35 provided so as to protrude from the distal end side lid member 31a of the release handle 31 to the distal end side. ing. The protruding cylindrical 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 can be covered with the stopper tube 23. A position adjusting stopper (position adjusting means) 28 is fixed to the proximal end portion of the stopper tube 23. The position adjusting stopper 28 fixes the stopper tube 23 to the projecting cylindrical portion 35 of the release handle 31 so as to be releasable. In this embodiment, the position adjusting stopper 28 has a screw member 28a. By engaging the member 28 a 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 adjustment stopper 28 (screw member 28a) to the distal end side of the projecting cylinder part 35 of the release handle 31 or to the proximal end side, the range of the axial length of the projecting cylinder part 35 Inside, the position with respect to the stent 5 of the distal end of the holding | suppressing part 23a can be adjusted. In addition, what is necessary is just to set the length of the axial direction of the protrusion cylinder part 35 in the range of 5-50 mm, for example.

  Next, a procedure for placing a stent using the stent delivery device of this embodiment will be described with reference to FIGS. For example, when a stent is placed so as to bypass the stomach and the intrahepatic bile duct in the abdominal cavity via the treatment instrument guide tube of the endoscope inserted into the stomach, as shown in FIG. Puncture with a puncture needle so as to reach the bile duct wall 62 through the abdominal cavity 63, pass through the guide wire, and after expanding the puncture holes of the gastric wall 61 and the bile duct wall 62 with a dilator or the like as necessary, The distal end portion of the catheter portion 2 is inserted through the puncture hole. 6 and 7, the operation is performed by moving the release lever 32 to the distal end of the groove 33 so that the distal end of the outer sheath 22 reaches the distal tip 24. A state in which the outer sheath 22 is slid to the distal end side, that is, a state in which the stent 5 arranged in the stent placement portion of the inner sheath 21 is held in the distal end portion of the outer sheath 22 in a reduced diameter state. Done in

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

  6 and 7, the release lever 32 is moved to the proximal end side of the groove 33 to move the outer sheath 22 to the proximal end with respect to the inner sheath 21 as shown in FIG. 9. Slide to the side. As the outer sheath 22 slides, the stent 5 is gradually exposed and expanded in diameter from the distal end side thereof, and the release lever 32 is moved to the proximal end of the groove 33, whereby as shown in FIG. Is exposed and expanded in diameter. Thereafter, the distal end of the catheter portion 2 is pulled out through the inside of the expanded stent 5 to complete the placement of the stent 5.

  Here, for comparison with the present embodiment, a case where a stent is placed using a conventional stent delivery device that does not include the stopper tube 23 as in the present embodiment is simply described with reference to FIGS. Explained. As shown in FIG. 12, from the state in which the distal end of the catheter portion 2 is inserted so as to reach the puncture hole of the bile duct wall 62 from the puncture hole of the stomach wall 61 through the abdominal cavity 63, as shown in FIG. When the outer sheath 22 is pulled out, the stomach wall 61 around the puncture hole is dragged by the frictional force with the outer sheath 22 being pulled and pulled toward the proximal end side. When the outer sheath 22 is completely pulled out, FIG. As shown, when the proximal end portion of the stent 5 is removed from the puncture hole of the stomach wall 61 and expands in the abdominal cavity 63, and the opening on the proximal end side of the stent 5 is placed in the abdominal cavity 63. In such an inappropriate state, leakage of bile and stomach contents to the abdominal cavity 63 may occur, so the procedure needs to be repeated.

  On the other hand, in the stent delivery device 1 of the present embodiment, as shown in FIGS. 8 to 10, in order to release the stent 5, the outer sheath 22 is slid to the proximal end side, and from inside the puncture hole. When pulling out, since 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, the stomach wall 61 around the puncture hole is dragged along with the withdrawal of the outer sheath 22. Therefore, it is prevented from being pulled toward the proximal end side. Therefore, the stent 5 can be placed in an appropriate position.

  In addition, the stopper tube 23 of the present embodiment has a notch 23b formed at the distal end thereof so as to have a semicircular cross section substantially perpendicular to the center axis thereof, and the remaining half-cylindrical cylindrical shape. 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 obstruction when the stent 5 expands in diameter.

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

  Here, the slit 231b is formed at a position opposed to each other by 180 degrees, and therefore, two pressing portions 231a having a substantially arc-shaped cross section are provided. The pressing portion 231a is configured to be elastically deformed outward. When the diameter of the stent 5 is expanded, the pressing portion 231a is elastically deformed outward by the pressing force at this time, and does not become an obstacle to the diameter expansion of the stent 5. I am doing so.

  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 locations so as to surround the stomach wall around the puncture hole. It is prevented that the stomach wall around the puncture hole is dragged by this and pulled toward the proximal end side.

  In this modification, the cylindrical portion has a larger diameter than the stopper tube 23. However, the holding portion is formed by forming a plurality of slits in the cylindrical portion having the same diameter as the stopper tube 23. May be configured. The number of slits 231b may be two or more, and three or more pressing portions 231a may be formed. Moreover, although the holding | maintenance part 231a is arrange | positioned substantially parallel to the central axis, you may carry out the plastic deformation so that the holding | maintenance part 231a may open outside, and you may make it the state opened beforehand. Furthermore, it is good also as a shape which curled (curved) the distal end part of the holding | suppressing part 231a outside.

  In the modification shown in FIG. 15, the holding portion has a cylindrical 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 on the cylindrical portion. A pair of slits 232b are formed in the direction along the central axis from the side, and the remaining portions (a pair of protrusions) are used as the pressing portions 232a. In this modification, the cylindrical portion of the distal end portion of the stopper tube 23 is set to have a larger diameter than that of the tubular portion of the modification shown in FIG. 14, and is set to a value larger than the diameter when the stent 5 is released. is doing.

  Here, the slit 232b is formed at a position facing each other by 180 degrees, and therefore, two pressing portions 232a having a substantially arc-shaped cross section are provided. Moreover, since the holding | maintenance part 232a of this modification is larger than the outer diameter at the time of the diameter expansion of the stent 5, since it does not become an obstacle of diameter expansion of the stent 5 as it is, it does not necessarily elastically deform. There is 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 locations so as to surround the tissue around the stomach puncture hole 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 pulled and pulled to the proximal end side.

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

  In still another modification shown in FIG. 16, a helical coil spring is provided at the distal end portion of the stopper tube 23, and this coil spring is used as the 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, a relatively wide range around the puncture hole can be pressed down as a whole by the biasing force of the coil spring 233 without becoming an obstacle. Note that one or more beam members for restricting expansion and contraction of the coil spring 233 in the direction along the central axis may be fixed.

  The embodiment described above is described for facilitating understanding of the present invention, and is 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.

DESCRIPTION OF SYMBOLS 1 ... Stent delivery apparatus 2 ... Catheter part 21 ... Inner sheath 22 ... Outer sheath 23 ... Stopper tube 23a, 231a, 232a, 233 ... Pressing part 28 ... Position adjustment stopper 28a ... Screw member 24 ... End tip 3 ... Operation part 31 ... Release handle 32 ... Release lever 33 ... Groove 35 ... Projecting cylinder 4 ... Guide wire 5 ... Stent 61 ... Gastric wall 62 ... Bile duct wall 63 ... Abdominal cavity

Claims (5)

A stent delivery device for placing a self-expanding stent in a puncture hole formed in a luminal organ wall,
An inner sheath having a stent placement portion for placing the stent on the outer peripheral surface near the distal end;
An outer sheath that is slidably inserted through the inner sheath and that holds the stent disposed in the stent placement portion in a reduced diameter state; and
The outer sheath is slidably inserted, and when the outer sheath is slid proximally with respect to the inner sheath and the distal end of the outer sheath is pulled out of the puncture hole, A stent delivery device comprising: a stopper tube having a holding portion that abuts at least a part of a surrounding luminal organ wall at a distal end portion thereof.   The said holding | suppressing part is notched so that the cross section orthogonal to the center axis may become a circular arc which is less than a semicircle or a semicircle at the distal end part of the said stopper tube. Stent delivery device.   The stent delivery according to claim 1, wherein the pressing portion is provided with at least one protrusion that elastically deforms outward as the stent expands in diameter at a distal end portion of the stopper tube. 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 a diameter of the expanded stent at a 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 a distal end of the large-diameter portion along a central axis of the large-diameter portion.

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