JP2019166132A - Stent - Google Patents

Abstract

To provide a stent which enables bypass surgery to be performed between organs with low invasion to a patient and with a small number of steps.SOLUTION: The stent comprises: a cylindrical stent body 10; a first magnetic member 12 formed of a material including a magnetic body and loosely fitted to a periphery of the stent body 10 in a movable manner in an axial direction of the stent body 10; a second magnetic member 14 formed of a material including a magnetic body and loosely fitted to a periphery of the stent body 10 in a movable manner in an axial direction of the stent body 10; and a regulation member 16 arranged between the first and second magnetic members 12, 14, and regulating an axial interval between the first and second magnetic members 12, 14. One or both of first and second magnetic bodies 12, 14 has a magnet, the regulation member 16 is formed of a material including biodegradable material.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a stent.

  As a treatment technique for biliary stricture or obstruction, attention has been paid to endoscopic ultrasound-guided biliary drainage (EUS-BD). EUS-BD is performed when treatment such as excision of a biliary stricture or an obstructed site cannot be performed, and a transduodenal papilla approach is difficult. EUS-BD is advantageous in that it does not reduce the patient's QOL, compared to percutaneous transhepatic biliary drainage, which is an external epilepsy.

  Specifically, the EUS-BD inserts an ultrasonic endoscope into the stomach or duodenum, punctures the bile duct or gallbladder from the stomach wall or duodenal wall with a puncture needle while observing the ultrasonic image in real time, and guide wire Is inserted into the bile duct or gallbladder, and a bypass stent is inserted and placed. This procedure enables biliary drainage in the form of implanting a stent in the body.

  In the case of placing a bypass connection stent between two organs, it is already known to form a fistula so that both organs communicate with each other in a state where adjacent organ walls are pressed against each other (see, for example, Patent Document 1). .

  Patent Document 1 discloses a gastric bypass system in which a gastric wall and an intestinal wall are sandwiched between two magnets and the gastric wall and the intestinal wall are in close proximity to each other, a fistula is formed at a site where the gastric wall and the intestinal wall are close to each other, and the fistula is placed through a stent. It is disclosed. In this gastric bypass system, a magnet is arranged in the stomach by the first endoscopic instrument, and another magnet is arranged in the intestine by the second endoscopic instrument.

Japanese Patent Laid-Open No. 2006-77896

  However, the gastric bypass system described in Patent Document 1 has a large number of treatment steps and is an invasive procedure for a patient. Specifically, the walls of adjacent organs (stomach and intestine) are brought close to each other, a magnet is placed in one organ (stomach) using the first endoscopic instrument, and the second endoscope Another magnet is placed in the other organ (intestine) using an instrument, both organ walls are pressed against each other by two magnets, and a stent is inserted and placed so as to pass through the hollow portion of both magnets. Thus, the number of steps required for the bypass operation is large, and it is necessary to use two endoscopic instruments, and the operation is complicated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a stent capable of performing an inter-organ bypass operation with minimal invasiveness and a small number of steps for a patient. .

  In order to achieve the above object, a stent according to the present invention comprises a cylindrical stent body and a material containing a magnetic material, and is loosely fitted on the outer periphery of the stent body so as to be movable in the axial direction of the stent body. A magnetic material member, a second magnetic material member made of a material containing a magnetic material, and loosely fitted on the outer periphery of the stent body so as to be movable in the axial direction of the stent body; and the first magnetic material member; A regulating member that is disposed between the first magnetic body member and regulates the axial distance between the first magnetic body member and the second magnetic body member. One or both of the magnetic member and the second magnetic member have magnets, and the restriction member is made of a material containing a biodegradable material.

  As described above, in the stent according to the present invention, the interval between the first magnetic member and the second magnetic member that are loosely fitted in the axial direction on the outer periphery of the stent body is regulated by the regulating member. It has become so. As a result, the stent can be fed to a target location in the body while maintaining a constant distance between the first magnetic member and the second magnetic member.

  Specifically, the stent is such that the first magnetic member is located in the first organ (eg, liver) and the second magnetic member is located in the second organ (eg, stomach). The stent is fed by the delivery device. When the required time elapses after the stent is inserted into the body, the regulating member made of the material containing the biodegradable material is biodegraded, and the first magnetic member and the second magnetic member act on the magnetic force. Attract below and get close. As a result, the wall of the first organ and the wall of the second organ are brought into pressure contact and fused. In this way, a fistula in which the first organ and the second organ are fused and communicated is formed, and the stent is inserted and placed in the fistula.

  In this way, since the stent is delivered once by the stent delivery device, the first magnetic body member and the second magnetic body member can be fed into the body together with the stent body while being spaced by the regulating member. The number of processes can be reduced compared to the conventional one. In addition, the stent can be placed using one ultrasonic endoscope. Therefore, an inter-organ bypass operation such as EUS-BD can be performed on a patient with minimal invasiveness and a small number of steps.

  In addition, the stent according to the present invention can be configured such that one of the first magnetic member and the second magnetic member is made of a material containing a biodegradable material.

  With this configuration, for example, when the first magnetic member disposed in the first organ (liver) is biodegraded when performing EUS-BD, the first magnetic member is changed to the second magnetic member. The attractive force acting on the member disappears, and the second magnetic member can be selectively dropped into the second organ (stomach).

  In the stent according to the present invention, both the first magnetic member and the second magnetic member can be made of a material containing a biodegradable material.

  With this configuration, the first magnetic member and the second magnetic member, which are foreign matters for the body, can be disassembled and discharged from the body or absorbed by the living body.

  In addition, when performing EUS-BD, the biodegradability of the first magnetic member disposed in the first organ (liver) is changed to the second magnetic member disposed in the second organ (stomach). It may be higher than the biodegradability. That is, the first magnetic member disposed in the first organ is biodegraded faster than the second magnetic member disposed in the second organ stomach. Thereby, the 2nd magnetic body member and stent main body which are arrange | positioned in a 2nd organ can be selectively dropped in a 2nd organ.

  In the stent according to the present invention, each of the first magnetic member and the second magnetic member may have a coil shape.

  With this configuration, the first magnetic member and the second magnetic member can be compressed and expanded in the axial direction and / or the radial direction. Thus, when the stent is loaded into the catheter portion of the stent delivery device, the first magnetic member and the second magnetic member can be loaded in a state compressed in the axial direction and / or the radial direction. Thereby, the volume of the catheter part required for loading can be reduced.

  In the stent according to the present invention, each of the first magnetic member and the second magnetic member may have a ring shape.

  Thereby, since the structure is simple, the manufacture of the first magnetic member and the second magnetic member is facilitated, and the distal end of the catheter portion of the stent delivery device can be easily loaded together with the stent body.

  In the stent according to the present invention, each of the first magnetic member and the second magnetic member may have a configuration in which a plurality of magnets are connected via a connecting portion.

  With this configuration, since a separation portion is formed in the connecting portion of the plurality of magnetic bodies in the circumferential direction, it becomes easy to load the distal end of the catheter portion of the stent delivery device together with the stent body in a radially compressed state.

  In the stent according to the present invention, the connecting portion may be made of a material containing a biodegradable material.

  With this configuration, the connecting portion is biodegraded in the body, and the annular structure of the first magnetic member and the second magnetic member is decomposed. Thereby, the 1st magnetic body member and the 2nd magnetic body member can be dropped from a stent main part.

  In the stent according to the present invention, the biodegradable material constituting the regulating member may include calcium phosphate. Calcium phosphate is also a component of bone and is easily decomposed and absorbed in vivo.

  In the stent according to the present invention, the first magnetic member and the second magnetic member may be flexible.

  With the configuration having this flexible member, when performing an inter-organ bypass operation such as EUS-BD, the first magnetic member and the second magnetic member are less likely to damage the organ wall, It becomes easy to load together with the stent body at the distal end of the catheter portion of the stent delivery device in a state of being compressed in the radial direction.

  In the stent according to the present invention, the first magnetic member and the second magnetic member may be magnetizable by a nuclear magnetic resonance imaging (MRI) apparatus.

  With this configuration, the magnetic force of the first magnetic member and the second magnetic member can be further increased by the high magnetic field generated by the MRI apparatus. Thereby, the press-contact force to an organ wall can be strengthened.

  In the stent according to the present invention, at least one of the first magnetic member and the second magnetic member may be a ferromagnetic material.

  With this configuration, it is possible to suppress the first magnetic member and the second magnetic member from dropping from the regulating member.

  ADVANTAGE OF THE INVENTION According to this invention, the stent which can perform an inter-organ bypass operation with few steps with few invasiveness with respect to a patient can be provided.

It is explanatory drawing which shows the usage example of the stent which concerns on the 1st Embodiment of this invention. 1 is a side view of a stent according to a first embodiment of the present invention. It is the sectional view on the AA line of the stent of FIG. (A) is explanatory drawing which shows the state (before stent expansion | deployment) with which the stent of FIG. 2 was loaded into the stent delivery apparatus, (b) is the state (during stent expansion | deployment) in which the stent is being extruded from a stent delivery apparatus. It is explanatory drawing shown. It is explanatory drawing which shows the state immediately after the stent of FIG. 2 was inserted in the body by the stent delivery apparatus. It is explanatory drawing which shows the state by which the two organ walls are press-contacted by the 1st magnetic body member and 2nd magnetic body member of the stent of FIG. It is explanatory drawing which shows the state which the 1st magnetic body member of the stent of FIG. 2 biodegraded. It is explanatory drawing which shows a mode that the 2nd magnetic body member of the stent of FIG. 2 falls from a stent main body. It is explanatory drawing which shows a mode that the 2nd magnetic body member and stent main body of the stent of FIG. It is a side view of the stent which concerns on the 2nd Embodiment of this invention. It is a side view of the stent which concerns on the 3rd Embodiment of this invention. It is a front view of the 1st and 2nd magnetic body member of the stent of FIG. It is a side view of the stent which concerns on the 4th Embodiment of this invention. It is a side view of the stent which concerns on the 5th Embodiment of this invention. It is a side view of the stent which concerns on the 6th Embodiment of this invention. It is a side view of the stent which concerns on the 7th Embodiment of this invention.

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

[First Embodiment]
The stent 1 according to the first embodiment of the present invention is suitably used for bypass connection between organs. Hereinafter, the stent 1 according to the present embodiment will be described by taking as an example a case where it is used for ultrasonic endoscopic biliary drainage (EUS-BD).

  FIG. 1 shows a state in which the stent 1 according to the present embodiment is placed in the body by the EUS-BD technique. A stenosis 55 exists near the papilla of the duodenum 54 where the biliary tracts such as the bile duct 52 and the gallbladder 53 merge. An EUS-BD operation is performed for a case in which treatment such as approaching and expanding the stenosis 55 from the nipple is not possible. As shown in FIG. 1, the stent 1 bypasses the bile duct 52 and the stomach 51 in the liver 50.

  FIG. 2 is a side view of the stent 1 according to the first embodiment. As shown in FIG. 2, the stent 1 includes a stent main body 10, a first magnetic member 12, a second magnetic member 14, and a regulating member 16.

  The stent main body 10 is formed in a long and thin cylindrical shape with a network structure made of metal (316L stainless steel, tantalum, cobalt alloy, Nitinol, etc.). The stent body 10 may be formed by laser cutting a metal tube, or may be formed by knitting a wire. The stent body 10 is a self-expanding stent, and automatically expands when delivered from a stent delivery device at a target position in the body. The stent body 10 may be a covered stent in which a metallic resin structure is covered with a synthetic resin film (silicon film, polyurethane film, ePTFE (expanded polytetrafluoroethylene) film, etc.). The stent body 10 has a length and a diameter that allow the bypass connection between the intrahepatic bile duct 52 and the stomach 51.

  The stent body 10 according to the present embodiment is made of metal, but may be a tube stent made of synthetic resin, or may be made of a biodegradable resin, a biodegradable metal, or the like. The stent body 10 according to the present embodiment is not limited to a self-expanding stent, and may be a non-expandable type having a constant diameter or a balloon-expandable type that is expanded by a balloon.

  The first magnetic body member 12 is a ring-shaped magnet having a hollow portion. The hollow portion has a size that allows the expanded stent 1 to be inserted. That is, the first magnetic member 12 is loosely fitted on the outer periphery of the stent body 10 so as to be movable in the axial direction of the stent body 10 after the stent is expanded. The second magnetic member 14 is also a ring-shaped magnet having the same shape and structure as the first magnetic member 12.

  The first magnetic member 12 and the second magnetic member 14 of the present embodiment are both magnets, but are not limited to this, and the first magnetic member 12 and the second magnetic member 14 are not limited thereto. At least one may include a magnet and the other may include a ferromagnetic member.

  The first magnetic body member 12 and the second magnetic body member 14 are loosely fitted to the stent body 10 so that the end faces of different polarities face each other. In other words, the first magnetic body member 12 and the second magnetic body member 14 are arranged so that attractive force acts on each other under the action of magnetic force.

  In the present embodiment, the stent 1 includes the first magnetic member 12 and the second magnetic member 14, but the number of magnetic members is not limited to two, and is three or more. May be. For example, the third magnetic member having the same structure as the first and second magnetic members 12 and 14 is arranged to be magnetically attached to the first magnetic member 12 or the second magnetic member 14. It may be.

  The first magnetic member 12 is made of a material containing a biodegradable material. The biodegradable material may contain, for example, calcium phosphate. Further, the first magnetic member 12 and the second magnetic member 14 may have flexibility so that the organ wall is not easily damaged.

  In the present embodiment, the first magnetic member 12 is made of a material containing a biodegradable material, but the second magnetic member 14 may also be made of a material containing a biodegradable material. When both the first magnetic member 12 and the second magnetic member 14 are made of a material containing a biodegradable material, their biodegradation rates may be different.

  The first magnetic member 12 and the second magnetic member 14 may be magnetizable by a nuclear magnetic resonance imaging (MRI) apparatus. The MRI apparatus can usually generate a static magnetic field of several Tesla. When the first magnetic member 12 and the second magnetic member 14 are arranged in the generated static magnetic field, they are more strongly magnetized. . Similarly, when at least one of the first magnetic member 12 and the second magnetic member 14 is made of a ferromagnetic material, the ferromagnetic material can be strongly magnetized by the MRI apparatus. .

  Further, the first magnetic member 12 and the second magnetic member 14 may be paramagnetic materials. In this case, the first magnetic body member 12 and the second magnetic body member 14 are magnetized in the presence of an external magnetic field and attract each other under the action of magnetic force.

  Next, the regulating member 16 will be described.

  As shown in FIGS. 2 and 3, the regulating member 16 is disposed between the first magnetic member 12 and the second magnetic member 14 on the outer periphery of the stent body 10, and the first magnetic member The distance between the stent 12 and the second magnetic member 14 in the stent axial direction is regulated. That is, the regulating member 16 functions as a spacer that maintains a constant axial interval between the first magnetic member 12 and the second magnetic member 14.

  The regulating member 16 has a cylindrical structure having a hollow portion through which the stent body 10 is inserted, and is freely fitted on the outer periphery of the expanded stent body 10. The regulating member 16 may be formed in a cylindrical structure by winding a belt-like member. The restriction member 16 of the present embodiment is loosely fitted to the expanded stent body 10 so as to be movable in the axial direction, but may be closely fitted to the expanded stent body 10 so as not to move. Good.

  Further, the regulating member 16 is not limited to a cylindrical structure, and may be a coil shape, or one or a plurality of plate-like or rod-like members on the outer periphery of the stent body 10 may be used as the first member. You may make it provide between the magnetic body member 12 and the 2nd magnetic body member 14. FIG. In short, the restricting member 16 may be any member that can keep a certain distance so that the first magnetic member 12 and the second magnetic member 14 do not come close to each other under the action of magnetic force.

  The regulating member 16 is made of a material containing a biodegradable material. The biodegradable material constituting the regulating member 16 and the first and second magnetic members 12 and 14 is not particularly limited as long as it is a material that is decomposed in vivo. Examples of biodegradable materials include biodegradable synthetic polymer materials such as polylactic acid, polyglycolic acid, polycaprolactone, and lactic acid / glycolic acid copolymer, biodegradable natural polymer materials such as collagen, magnesium, and zinc And biodegradable metal materials such as

  Next, the usage method of the stent 1 of this embodiment is demonstrated.

  The procedure of the EUS-BD operation is roughly as follows. First, an ultrasonic endoscope is inserted into the stomach 51, and a puncture needle is punctured from the stomach 51 into the intrahepatic bile duct 52. Next, a guide wire is passed through the puncture route. Then, the catheter portion 40 of the stent delivery device is inserted into the intrahepatic bile duct 52 along the guide wire, and the stent 1 is placed from the intrahepatic bile duct 52 to the stomach 51. Hereinafter, the insertion and placement of the stent 1 in the body will be specifically described.

  FIG. 4A is an explanatory view showing a state in which the stent 1 is loaded in the stent delivery device (before deployment of the stent), and FIG. 4B is a state in which the stent 1 is being pushed out of the stent delivery device (stent FIG. In general, a stent delivery device is connected to an elongated catheter part 40 inserted into a patient's body via a treatment instrument guide tube of an ultrasonic endoscope, and a proximal end side of the catheter part 40, and is connected to the body outside the body. And an operation section for operating the catheter section 40 of the above. FIG. 4 shows a configuration of a portion of the stent delivery device on the distal end side of the catheter unit 40.

  The catheter unit 40 includes an inner sheath (inner tube) 42 and an outer sheath (outer tube) 44. Each of the inner sheath 42 and the outer sheath 44 is made of an elongated tube having flexibility, and the inner sheath 42 has a larger inner diameter than the inner sheath 42 so that the inner sheath 42 can slide inside the outer sheath 44. It is inserted.

  The lumen of the inner sheath 42 is configured such that a guide wire used as a guide for inserting the catheter unit 40 into the patient's body can be inserted. The distal end 42a of the inner sheath 42 is provided with a taper that reduces the diameter of the puncture hole drilled by the puncture needle toward the distal portion so that the catheter portion 40 can be inserted. A portion 48 is provided.

  In the vicinity of the distal end of the inner sheath 42, a fixing ring 46 is integrally fixed, and this fixing ring 46 abuts on the proximal end 10a of the stent 1 and thereby the proximal end 10a of the stent 1. The position is defined. A portion from the fixing ring 46 to the distal end side is a stent placement portion. In the stent placement portion, the stent 1 is inserted into the outer sheath 44 in a state of a reduced diameter, and the inner sheath 42 is inserted into the lumen portion of the stent 1. That is, the stent 1 is accommodated in the annular space between the inner sheath 42 and the outer sheath 44.

  In the state shown in FIG. 4A, the stent 1 can be expanded (deployed) by relatively moving the inner sheath 42 and the outer sheath 44. Specifically, since the fixing ring 46 is fixed to the inner sheath 42 side, and the stent 1 is in contact with the fixing ring 46, the inner sheath 42, the fixing ring 46 and the stent 1 are relatively opposed to the outer sheath 44. By moving, the stent 1 can be exposed and expanded from within the outer sheath 44.

  FIG. 4B shows a state of expansion of the stent 1 when the outer sheath 44 is relatively moved in the direction of arrow B. A portion of the stent 1 exposed from the outer sheath 44 is expanded from its contracted state by its own elastic force. When the outer sheath 44 is further moved relative to the direction of arrow B from the state of FIG. 4B, the entire stent 1 is expanded. After the stent 1 is expanded, the expanded (deployed) stent 1 can be placed at a target position in the body by pulling the catheter portion 40 out of the body.

  FIG. 5 shows a state in which the stent 1 is inserted into the body by the stent delivery device. The stent body 10 placed in the body has one end in the intrahepatic bile duct 52 and the other end in the stomach 51, and bypasses both organs. FIG. 5 schematically shows the positional relationship between the liver 50 and the stomach 51. As shown in FIG. 5, the first magnetic member 12 is located in the liver 50, and the second magnetic member 14 is located in the stomach 51. Then, the first magnetic member 12 and the second magnetic member 14 are arranged with a predetermined interval by the restriction member 16.

  When a predetermined time (for example, about several tens of minutes to one hour) elapses in the state of FIG. 5, the regulating member 16 is biodegraded, and as shown in FIG. 6, the first magnetic body member 12 and the second magnetic body The member 14 is attracted by the action of magnetic force and comes close.

  In the state shown in FIG. 6, the wall 50a of the liver 50 and the wall 51a of the stomach 51 are pressed against each other by the first magnetic member 12 and the second magnetic member 14, and when the required time elapses, The wall 51a of the stomach 51 adheres to form a fistula communicating between both organs. At that time, if the perforated portions where the organ tissue is damaged are brought into contact with each other to re-form the tissue, adhesion occurs, and a continuous fistula is easily formed.

  FIG. 7 is an explanatory view showing a state in which the first magnetic member 12 is biodegraded. As shown in FIG. 7, when the first magnetic member 12 located in the liver 50 is made of a material containing a biodegradable material, when the first magnetic member 12 is biodegraded, The attractive force acting on the second magnetic member 14 located in the stomach 51 from the first magnetic member 12 disappears. As a result, as shown in FIG. 8, the second magnetic member 14 moves in the stent body 10 in the axial direction and falls into the stomach 51.

  Next, another method of using the stent 1 of this embodiment will be described.

  By using the stent 1 according to this embodiment, a fistula communicating between the stomach 51 and the intestine 56 can be formed and bypass-connected. 5 to 7 show the bypass connection between the liver 50 (intrahepatic bile duct 52) and the stomach 51, the principle of bypassing the two organs is the same. Therefore, in the following description, FIGS.

  First, the stent 1 is inserted into the body using a stent delivery device (see FIG. 5). Specifically, the first magnetic member 12 is located in the intestine 56 and the second magnetic member 14 is located in the stomach 51. Then, the first magnetic member 12 and the second magnetic member 14 are arranged with a predetermined interval by the restriction member 16.

  Next, when a predetermined time (for example, about several tens of minutes to one hour) elapses, the regulating member 16 is biodegraded, and the first magnetic member 12 and the second magnetic member 14 are attracted by the action of magnetic force. And close to each other (see FIG. 5). As a result, the wall 56a of the intestine 56 and the wall 51a of the stomach 51 are brought into pressure contact with each other by the first magnetic member 12 and the second magnetic member 14, and a fistula communicating between the two organs thus formed is formed. The Adhesion occurs about one week after surgery.

  Next, after the adhesion occurs, the first magnetic member 12 located in the intestine 56 is biodegraded, and the attractive force acting on the second magnetic member 14 disappears (see FIG. 6). As a result, as shown in FIG. 8, the stent body 10 together with the second magnetic member 14 is selectively dropped into the stomach 51.

  Next, the effect of the stent 1 which concerns on this embodiment is demonstrated.

  In the stent 1 according to this embodiment, the interval between the first magnetic member 12 and the second magnetic member 14 that are loosely fitted in the axial direction on the outer periphery of the stent body 10 is regulated by the regulating member 16. It has come to be. Thereby, the stent 1 can be sent to a target location in the body while maintaining a constant distance between the first magnetic member 12 and the second magnetic member 14.

  Specifically, the stent 1 is moved by the catheter portion 40 of the stent delivery device so that the first magnetic member 12 is located in the liver 50 and the second magnetic member 14 is located in the stomach 51. It is sent. When the required time elapses after the stent 1 is inserted into the body, the regulating member 16 made of a biodegradable material is biodegraded, and the first magnetic member 12 and the second magnetic member 14 have magnetic forces. Attract and close under action. As a result, the wall 50a of the liver 50 and the wall 51a of the stomach 51 are brought into pressure contact and fused. In this way, a fistula in which the liver 50 and the stomach 51 are fused and communicated is formed, and the stent 1 is inserted and placed in the fistula.

  In this way, the first magnetic body member 12 and the second magnetic body member 14 can be fed into the body together with the stent body 10 by a single feeding step of the stent 1 by the stent delivery device. Compared to the number of processes, In addition, the stent 1 can be placed using one ultrasonic endoscope. Therefore, an inter-organ bypass operation such as EUS-BD can be performed on a patient with minimal invasiveness and a small number of steps.

  Further, the stent 1 according to the present embodiment has a configuration in which the first magnetic member 12 is made of a material containing a biodegradable material. With this configuration, for example, when the first magnetic member 12 disposed in the liver 50 is biodegraded when performing EUS-BD, the first magnetic member 12 to the second magnetic member 14 are biodegraded. Thus, the attractive force acting on the second magnetic member 14 disappears, and the second magnetic member 14 can be selectively dropped into the stomach 51.

  In addition, the stent 1 according to the present embodiment may be configured such that both the first magnetic member 12 and the second magnetic member 14 are made of a material containing a biodegradable material. Thereby, the 1st magnetic body member 12 and the 2nd magnetic body member 14 which are foreign bodies with respect to a body can be decomposed | disassembled, and can be discharged | emitted out of a body or can be bioabsorbed.

  In addition, the biodegradability of the first magnetic member 12 disposed in the liver 50 when performing EUS-BD is greater than the biodegradability of the second magnetic member 14 disposed in the stomach 51. May be high. That is, the first magnetic member 12 disposed in the liver 50 is biodegraded faster than the second magnetic member 14 disposed in the stomach 51. Thereby, the 2nd magnetic body member 14 and the stent main body 10 which are arrange | positioned in the stomach 51 can be selectively dropped in the stomach 51. FIG.

  Further, in the stent 1 according to this embodiment, the first magnetic member 12 and the second magnetic member 14 each have a ring shape. Since the structure is simple, the manufacture of the first magnetic member 12 and the second magnetic member 14 is facilitated, and it is easy to load the distal end of the catheter portion 40 of the stent delivery device together with the stent body 10.

  Moreover, in the stent 1 according to the present embodiment, the biodegradable material constituting the regulating member 16 may contain calcium phosphate. Calcium phosphate is also a component of bone and is easily broken down and absorbed in vivo.

  In the stent 1 according to this embodiment, the first magnetic member 12 and the second magnetic member 14 may have flexibility. With the configuration having this flexible member, when performing an inter-organ bypass operation such as EUS-BD, the first magnetic member and the second magnetic member are less likely to damage the organ wall, It becomes easy to load together with the stent body at the distal end of the catheter portion of the stent delivery device in a state of being compressed in the radial direction.

  In the stent 1 according to this embodiment, the first magnetic member 12 and the second magnetic member 14 may be magnetizable by a nuclear magnetic resonance imaging (MRI) apparatus. With this configuration, the magnetic force of the first magnetic member 12 and the second magnetic member 14 can be further increased by the high magnetic field generated by the MRI apparatus. Thereby, the press-contact force to an organ wall can be strengthened.

[Second Embodiment]
Next, a stent 1A according to a second embodiment of the present invention will be described.

  The stent 1A according to this embodiment is different from the first embodiment having a ring shape in that the first magnetic member 22 and the second magnetic member 24 have a coil shape. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same configurations, and detailed description thereof is omitted.

  FIG. 10 is a side view of the stent 1A according to the present embodiment. The first magnetic member 22 is a coil-shaped magnet having a hollow portion, and can be compressed and expanded in the axial direction and / or the radial direction. The second magnetic member 24 has the same shape and structure as the first magnetic member 22. Thus, when the stent 1A is loaded into the catheter portion 40 of the stent delivery device, the first magnetic member 22 and the second magnetic member 24 are loaded in a compressed state in the axial direction and / or the radial direction. be able to. Thereby, the volume of the catheter part 40 required for loading can be reduced.

  When the stent 1A is delivered from the catheter portion 40 of the stent delivery device at a target position in the body, the stent body 10 automatically expands, and the compressed first and second magnetic members 22 and 2 in the coil shape are compressed. The magnetic member 24 expands.

  Each of the coil-shaped first magnetic member 22 and second magnetic member 24 has an S pole at one end and an N pole at the other end. The ends having opposite polarities are arranged to face each other, and when the regulating member 16 is biodegraded in the body, the first magnetic member 22 and the second magnetic member 24 are under the action of magnetic force. Attract one another.

[Third Embodiment]
Next, a stent 1B according to a third embodiment of the present invention will be described.

  The stent 1B according to the present embodiment has a ring shape in that the first magnetic member 32 and the second magnetic member 34 are each configured by connecting a plurality of magnets 36 via connecting portions 38. This is different from the first embodiment. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same configurations, and detailed description thereof is omitted.

  FIG. 11 is a side view of the stent 1B according to the present embodiment, and FIG. 12 is a front view of the first magnetic member 32 included in the stent 1B. The first magnetic body member 32 has an annular shape having a hollow portion, and includes four magnets 36 and strip-like or plate-like connecting portions 38 that connect the magnets 36 to each other. The number of magnets 36 is four, but is not limited to this, and may be one or any number. The second magnetic member 34 has the same shape and structure as the first magnetic member 32.

  The first magnetic body member 32 and the second magnetic body member 34 are arranged so that the magnets 36 included in the first magnetic body member 32 and the second magnetic body member 34 are opposed to each other. Have come to attract each other. With this configuration, the portion of the organ wall that is pressure-contacted can be selectively limited to the portion of the magnet 36.

  The connection part 38 is comprised from the material containing a biodegradable material. Thereby, the connection part 38 is decomposed | disassembled in a body, and the cyclic | annular structure of the 1st magnetic body member 32 and the 2nd magnetic body member 34 is decomposed | disassembled. Thereby, the first magnetic body member 32 and the second magnetic body member 34 can be detached from the stent body 10. The biodegradation speed of the connecting portion 38 can be changed by changing the thickness of the connecting portion 38.

[Fourth Embodiment]
Next, a stent 1C according to a fourth embodiment of the present invention will be described.

  The stent 1C according to the present embodiment is different from the first embodiment in that a locking portion 10c having an enlarged diameter is provided at both ends of the stent body 10. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same configurations, and detailed description thereof is omitted.

  FIG. 13 is a side view of the stent 1C according to the present embodiment. Both ends of the cylindrical stent body 10 are expanded in diameter to form a locking portion 10c. The diameter of the locking portion 10 c increases toward the end, and the maximum diameter is larger than the diameter of the hollow portion of the first and second magnetic members 12 and 14. The locking portion 10c prevents the first and second magnetic members 12 and 14 from falling off the stent body 10.

[Fifth Embodiment]
Next, a stent 1D according to a fifth embodiment of the present invention will be described.

  The stent 1D according to the present embodiment is different from the first embodiment in that convex locking portions 10d are provided at both ends of the stent body 10. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same configurations, and detailed description thereof is omitted.

  FIG. 14 is a side view of the stent 1D according to the present embodiment. Convex locking portions 10 d are formed at both ends of the cylindrical stent body 10. There may be one or more convex locking portions 10d at each end. Further, the convex locking portion 10d may be formed in an annular shape on the outer periphery of each end portion. The convex locking portions 10d make it difficult for the first and second magnetic members 12 and 14 to fall off the stent body 10.

[Sixth Embodiment]
Next, a stent 1E according to a sixth embodiment of the present invention will be described.

  The stent 1E according to the present embodiment is different from the first embodiment in that a locking portion 10c having an enlarged diameter is provided at one end portion of the stent body 10. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same configurations, and detailed description thereof is omitted.

  FIG. 15 is a side view of the stent 1E according to the present embodiment. One end portion of the cylindrical stent body 10 is expanded in diameter to form a locking portion 10c. The diameter of the locking portion 10 c increases toward the end, and the maximum diameter is larger than the diameter of the hollow portion of the first and second magnetic members 12 and 14. By providing the locking portion 10c only at one end portion on the second organ side, it is possible to prevent the bile duct from falling off and to selectively drop the stent body into the second organ (stomach).

[Seventh Embodiment]
Next, a stent 1F according to a seventh embodiment of the present invention will be described.

  The stent 1F according to the present embodiment is different from the first embodiment in that a convex locking portion 10d is provided at one end of the stent body 10. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same configurations, and detailed description thereof is omitted.

  FIG. 16 is a side view of the stent 1F according to the present embodiment. A convex locking portion 10 d is formed at one end of the cylindrical stent body 10. There may be one or more convex locking portions 10d at the end. Further, the convex locking portion 10 d may be formed in an annular shape on the outer periphery of one end portion of the stent body 10. By providing the locking portion 10c only at one end portion on the second organ side, it is possible to prevent the bile duct from falling off and to selectively drop the stent body into the second organ (stomach).

  In the first to seventh embodiments, EUS-BD has been described as an example, but the application is not limited to this. The stent of the present invention is generally a technique for bypassing two organs (gastrointestinal tract, biliary tract, etc.), and can be suitably used for fisturing the walls of two organs through which the stent is inserted to form a fistula It is. For example, it can also be suitably used when bypassing the stomach and intestines.

  As described above, the present invention has an effect that an inter-organ bypass operation can be performed on a patient with minimal invasiveness and a small number of steps, and is useful for all stents.

1, 1A, 1B, 1C, 1D, 1E, 1F Stent 10 Stent body 10c, 10d Locking portion 12, 22, 32 First magnetic member 14, 24, 34 Second magnetic member 16 Restricting member 36 Magnet 38 connecting part 40 catheter part 42 inner sheath 44 outer sheath 46 fixing ring 50 liver 50a liver wall 51 stomach 51a stomach wall 52 bile duct 53 gall bladder 54 duodenum 55 bile duct stenosis part 56 intestine 56a intestinal wall

Claims (11)

A cylindrical stent body;
A first magnetic body member made of a material containing a magnetic body and loosely fitted to the outer periphery of the stent body so as to be movable in the axial direction of the stent body;
A second magnetic member made of a material containing a magnetic body and loosely fitted to the outer periphery of the stent body so as to be movable in the axial direction of the stent body;
A restricting member that is disposed between the first magnetic member and the second magnetic member and restricts the axial distance between the first magnetic member and the second magnetic member; ,
The stent is characterized in that one or both of the first magnetic member and the second magnetic member has a magnet, and the regulating member is made of a material containing a biodegradable material.   The stent according to claim 1, wherein one of the first magnetic member and the second magnetic member is made of a material containing a biodegradable material.   The stent according to claim 1, wherein both the first magnetic member and the second magnetic member are made of a material containing a biodegradable material.   The stent according to any one of claims 1 to 3, wherein each of the first magnetic member and the second magnetic member has a coil shape.   The stent according to any one of claims 1 to 3, wherein each of the first magnetic member and the second magnetic member has a ring shape.   The first magnetic member and the second magnetic member each have a configuration in which a plurality of magnets are connected via a connecting portion. The described stent.   The stent according to claim 6, wherein the connecting portion is made of a material containing a biodegradable material.   The stent according to any one of claims 1 to 7, wherein the biodegradable material constituting the regulating member includes calcium phosphate.   The stent according to any one of claims 1 to 8, wherein the first magnetic member and the second magnetic member are flexible.   The stent according to any one of claims 1 to 9, wherein the first magnetic member and the second magnetic member can be magnetized by a nuclear magnetic resonance imaging (MRI) apparatus.   The stent according to any one of claims 1 to 10, wherein at least one of the first magnetic member and the second magnetic member is a ferromagnetic material.

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