WO2008001865A1 - Covered stent and method of producing covered stent - Google Patents

Covered stent and method of producing covered stent Download PDF

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Publication number
WO2008001865A1
WO2008001865A1 PCT/JP2007/063034 JP2007063034W WO2008001865A1 WO 2008001865 A1 WO2008001865 A1 WO 2008001865A1 JP 2007063034 W JP2007063034 W JP 2007063034W WO 2008001865 A1 WO2008001865 A1 WO 2008001865A1
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WO
WIPO (PCT)
Prior art keywords
stent
covered stent
covered
cover material
diameter
Prior art date
Application number
PCT/JP2007/063034
Other languages
French (fr)
Japanese (ja)
Inventor
Kouta Inoue
Yoshihide Toyokawa
Masaru Tanaka
Masatsugu Shimomura
Original Assignee
Zeon Medical Inc.
National University Corporation Hokkaido University
Japan Science And Technology Agency
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zeon Medical Inc., National University Corporation Hokkaido University, Japan Science And Technology Agency filed Critical Zeon Medical Inc.
Priority to JP2008522632A priority Critical patent/JPWO2008001865A1/en
Publication of WO2008001865A1 publication Critical patent/WO2008001865A1/en

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Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
    • A61L31/08—Materials for coatings
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/04—Hollow or tubular parts of organs, e.g. bladders, tracheae, bronchi or bile ducts
    • A61F2/06—Blood vessels
    • A61F2/07—Stent-grafts
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/82—Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86—Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
    • A61F2/89—Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02—Prostheses implantable into the body
    • A61F2/04—Hollow or tubular parts of organs, e.g. bladders, tracheae, bronchi or bile ducts
    • A61F2/06—Blood vessels
    • A61F2/07—Stent-grafts
    • A61F2002/075—Stent-grafts the stent being loosely attached to the graft material, e.g. by stitching

Definitions

  • the present invention is suitably used to expand a stenosis for the purpose of securing a body lumen when a stenosis occurs in a body lumen such as a bile duct, blood vessel, trachea, esophagus and urethra.
  • the present invention relates to a covered stent and a method for manufacturing the covered stent.
  • a stent is generally a cylindrical member in which metal wires are formed in a mesh shape, and can expand and contract in the radial direction.
  • the stent 102 is inserted into a body lumen by a delivery catheter 100 as shown in FIG. 5, for example, with the outer diameter contracted, and placed in a stenosis.
  • the outer diameter of the stent 102 can be expanded at this indwelling position to secure the lumen of the stenosis.
  • 101 indicates an outer tube (sheath) of the delivery catheter
  • 103 indicates an inner tube
  • 104 indicates a tip.
  • a stent is a member in which a metal wire is formed in a mesh shape, it grows so that a tumor tissue or the like enters the inside of the stent from the gap portion of the wire constituting the stent, so that the early stage of stenosis There was a concern about recurrence. For this reason, by providing a cover material made of a resin on the outer periphery of the stent, it is possible to prevent the invasion of tumor tissue, to suppress early recurrence of stenosis, and to suppress the growth of tumor tissue etc. in the body lumen. Coverable stents are also available.
  • Patent Document 1 includes a ring-shaped stent unit configured by a zigzag-shaped wire continuously formed in the circumferential direction and capable of expanding a contracted state force in the radial direction, and configures this stent unit. It is formed by connecting at least one of the zigzag folded ends of the wire and at least one folded end of the zigzag of the wire in another stent unit axially adjacent to the stent unit. Stent, and stent A covered stent is disclosed in which a cover film is wound around the outer periphery! By having this shape, the stent according to Patent Document 1 has excellent flexibility in a contracted state, can be easily inserted into a body lumen, and can easily maintain an expanded state. In addition, the risk of damaging the inner wall of the body lumen and the cover film wound around the outer periphery of the stent can be reduced.
  • Patent Document 2 discloses a stent including a tube-shaped flexible body having a web structure in which a tube wall portion can transfer a non-expanded state force to an expanded state.
  • This web structure has three parts in the pattern where each web is positioned at an angle to each other, thus minimizing its contraction when the stent is expanded and extremely flexible in the unexpanded state. Excellent in properties. Furthermore, it can have a very stable structure in the expanded state.
  • Patent Document 1 International Publication No. WO2006Z001367
  • Patent Document 2 Japanese Translation of Special Publication 2002-524135
  • Such a conventional covered stent cover material includes a method of dipping a bare stent into a resin solution, or a film of a resin coated on a bare stent and bonded with an adhesive or the like. In this way, the stent body and the cover material have not been peeled off.
  • the cover film becomes very thick.
  • the film of the resin is bonded by an adhesive, the part where the adhesive has hardened becomes very hard, so the covered stent cannot be placed without following the movement and bending of the body lumen.
  • the position force deviates, or when the radial stiffness is too high to irritate the living tissue, complications may occur due to the placement of the covered stent.
  • the cover material is covered without reducing the diameter of the stent, and therefore, the remaining cover material when the diameter is reduced in the manufacturing process is folded.
  • the cover material is bulky, and there is a problem that it is difficult to enter a sheath having a small diameter used for stent placement.
  • the cover can be covered without reducing the diameter.
  • the cover material was covered and the diameter of the cover material was reduced, the remaining cover material was folded, so that the folded cover materials were sticking to each other, and the diameter expansion of the covered stent was likely to occur.
  • the covered stent is inserted into the body lumen using a delivery catheter or the like, there is also a problem that the covered stent cannot be easily placed.
  • the object of the present invention is to hold the cover member on the stent body without using an adhesive, and to peel off! /, Which can follow the bending of the body lumen with less irritation to the body lumen wall. It is another object of the present invention to provide a covered stent that can function stably at that position and a manufacturing method thereof.
  • the covered stent (10) of the present invention includes a cylindrical stent (20) and a cover material (30) provided on an outer peripheral portion of the stent, and is used by being placed in a body lumen.
  • the covered stent is a radial stiffness of the stent, Rfs, the bending stiffness of the stent in the long axis direction is Afs, the radial stiffness of the covered stent is Rfc, and the bending stiffness of the covered stent in the long axis direction is Afc.
  • the cover material is 1.2 to 3.0 along the circumferential direction of the stent in the expanded state of the stent.
  • the film is stretched twice.
  • the radial stiffness (Rfs, Rfc) of the stent and the covered stent can be measured using an MSI Radial Expansion Force Gage RX500-01 (manufactured by MSI) in an atmosphere of 37 ° C. According to this, the repulsive force can be measured by uniformly reducing and expanding the entire circumference in the radial direction of the stent and the covered stent.
  • Figure 3 shows how to measure the bending stiffness (A fs, Afc) in the major axis direction.
  • a core rod 133 having an outer diameter substantially equal to the inner diameter of the stent 130 or the covered stent 131 is inserted into the inner lumen of the stent 130 or the covered stent 131 and fixed vertically.
  • the core rod 133 is inserted so that the partial force in which the stent 130 or the covered stent 131 and the core rod 133 do not overlap each other is 20 mm in the lengthwise direction.
  • the end 135 of the core rod 133 on the side inserted into the stent 130 or the covered stent 131 is aligned with the surface position and fixed with a vise.
  • the part that does not overlap with the core rod 133 Push the force gauge 138 at the position where the distance from the end 136 of the core rod 133 on the side of the stent 130 or the covered stent 131 of the minute stent 130 or the covered stent 131 to the major axis direction. Measure the repulsive force when bent so that the angle is 60 °. These are performed using a force gauge 138 in an atmosphere of 37 ° C.
  • the draw ratio Mc of the cover material is the following formula:
  • Mc (the length in the circumferential direction of the covered stent in the expanded state)
  • Z (the length in the circumferential direction of the cover material in the unstretched state)
  • the length of the covered stent in the expanded state in the circumferential direction is measured.
  • the cover material is cut along the long axis direction, and the cover material is peeled off from the stent.
  • the circumferential length of the cover material in an unstretched state from which the stress has been removed is measured. From these measurement results, the draw ratio of the cover material can be specified based on the above formula.
  • the cover material is stretched 1.2 to 3.0 times along the circumferential direction of the stent in the expanded state of the stent, and 1.2 to 2.5 times. Is more preferable.
  • the diameter expansion rate is preferably more than 80% and more than 90%.
  • the “expansion ratio” is a value obtained by (outer diameter of covered stent Z outer diameter of stent) X 100.
  • the diameter expansion rate falls within the above range, the stent body force cover material can be prevented from falling off, and the covered stent can be prevented from deviating from the bile duct.
  • the diameter expansion ratio is in the above range, the narrowed portion can be sufficiently expanded, and the function of the covered stent, that is, the function of ensuring a sufficient lumen. And thus the lumen patency can be lengthened.
  • the structure of the stent used in the covered stent of the present invention is not particularly limited.
  • the stent used in the present invention has a cover material in which the gap formed in the metal wire mesh is narrow to some extent. It is preferable to have a structure that does not enter the inside.
  • the cover material (30) has an initial elastic modulus of 50. It is preferably kPa or less. According to such a configuration, it is possible to keep the value of AfcZAfs small, and thereby it is possible to more easily place in the body lumen, and to place more stably at the position.
  • Initial elastic modulus refers to the value measured first among the elastic modulus of the cover material. The initial elastic modulus is measured by holding the cover material at both ends with a clip and pulling it in the opposite direction.
  • the relational force between the radial rigidity Rfc of the covered stent and the bending rigidity Afc of the long axis of the stent is 30 ⁇ RfcZAfc ⁇ 100.
  • the cover material (30) is made of a hard cam membrane. According to such a configuration, it is possible to reduce the value of the bending rigidity Afc in the major axis direction of the covered stent in which the flexibility of the cover material is high.
  • Her cam membrane refers to a polymer film having a her cam structure, and in the two cam structure, a plurality of holes having a substantially constant hole diameter are regularly arranged. Means a porous structure. In addition, the hole may penetrate through the other surface on the opposite side of the surface force of the honeycomb film, or may not penetrate.
  • the two-cam structure has a hexagonal structure continuously if the polymer film has a structure in which numerous small holes are regularly arranged on the film, such as a honeycomb. It does not have to be a deployed structure.
  • the cover material (30) may be a knitted fabric.
  • Such a configuration has the effect of reducing the value of AfcZAfs.
  • knitted fabric is not particularly limited, but it is preferable because, for example, a knitted fabric force such as stockings is thin and stretchable, and it is difficult to stick to each other even when folded when the stent is contracted.
  • the covered stent (10) of the present invention preferably has a radial rigidity Rfc of 15 N or less and a bending rigidity Afc in the major axis direction of 0.3 N or less. According to such a configuration, there is little effect on the luminal tissue wall in the body, and there is an effect.
  • the method of manufacturing the force bar stent (10) of the present invention used by being placed in a body lumen is a stent diameter reduction process in which the stent is reduced in diameter until the outer diameter becomes 1Z3 to 2Z3. And a cover material coating step of covering the outer peripheral portion of the reduced diameter stent with a cover material.
  • the covered stent of the present invention by placing the bending rigidity in the major axis direction and the rigidity in the radial direction within appropriate ranges, the placement in the body lumen can be facilitated, and the position can be maintained after the placement. It is possible to provide a function of stably securing the body lumen in the position.
  • the diameter of the stent is reduced to a predetermined size, and then the outer peripheral portion of the stent is covered with a cover material without using an adhesive or the like.
  • the cover material can be hugged to the stent. For this reason, indwelling in a body lumen can be facilitated, and the risk of occurrence of complications can be suppressed.
  • FIG. 1 is a perspective view showing a covered stent according to an embodiment of the present invention.
  • FIG. 2 is a schematic view including a method for manufacturing a covered stent according to an embodiment of the present invention.
  • FIG. 3 is a schematic diagram showing a method for measuring bending stiffness Afs and Afc in the major axis direction of a stent and a covered stent.
  • FIG. 5 is a plan view showing a stent delivery catheter with a stent mounted thereon. Explanation of symbols
  • FIG. 1 is a perspective view showing a covered stent according to an embodiment of the present invention.
  • the covered stent 10 according to the embodiment of the present invention includes a cylindrical stent 20 and a cover member 30 provided on the outer peripheral portion of the stent 20.
  • the radial stiffness of the stent 20 is Rfs
  • the bending stiffness in the major axis direction of the stent 20 is Afs
  • the radial stiffness of the covered stent 10 is Rfc
  • the bending stiffness in the major axis direction of the covered stent 10 is When Afc, Rfc / Rfs ⁇ l.5 and AfcZAfs ⁇ 2.0 are satisfied.
  • the cover member 30 is used while being expanded by 1.2 to 3.0 times along the circumferential direction of the stent 20 in the expanded state of the stent 20.
  • the stent used for the covered stent according to the embodiment of the present invention is not particularly limited in its structure. Among them, it is preferable that the stent has a structure in which the cover material narrowed to some extent by the mesh of the metal wire S does not enter the inside of the stent through the mesh space due to compression of the tumor tissue or the like.
  • the stent is configured by a zigzag-shaped wire continuously formed in the circumferential direction, for example, as in the stent described in Patent Document 1, and the contracted state force can be expanded in the radial direction.
  • the stent is preferably formed by connecting two folded ends.
  • the stent includes a tube-like flexible body having a web structure in which the tube wall portion can transfer the non-expanded state force to the expanded state as in the stent described in Patent Document 2.
  • the web structure is preferably a stent such that in its pattern, each web has three parts that are arranged at an angle to each other.
  • the cover material 30 used for the covered stent 10 according to the embodiment of the present invention is stretched 1.2 to 3.0 times along the circumferential direction of the stent in a diameter-expanded state of the stent. 2. It is preferable that the film is stretched 5 times.
  • the initial elastic modulus of the cover material is 20 kPa or less.
  • the initial elastic modulus is If the value is larger than the prescribed value, the diameter expansion of the covered stent 10 is liable to occur, and the bending rigidity Afc in the long axis direction is increased.
  • the initial elastic modulus is the value measured first among the elastic modulus of the cover material. The initial elastic modulus is measured by holding both ends of the cover material with a clip and pulling them in opposite directions on a straight line. Examples of specific methods for measuring the initial elastic modulus will be described in detail in Examples.
  • the material of the cover material 30 is preferably made of a Hercam film!
  • a “her cam membrane” refers to a polymer film having a harm structure.
  • the Hercam structure means a porous structure in which a plurality of holes having a substantially constant hole diameter are regularly arranged (see International Publication No. WO2005 Z051450). Therefore, it is only necessary that the polymer film has a structure in which innumerable small holes are regularly formed on the film like a honeycomb, and the hexagonal structure is continuously developed. There is no need.
  • the average hole diameter of the holes constituting the Hercam structure is preferably 0.1-100 ⁇ m, and 0.1-20 1! 1 is preferably 0. 5 ⁇ : More preferably, LO / zm.
  • the hole diameter refers to the diameter of the maximum inscribed circle with respect to the opening shape of the hole.
  • the aperture shape is circular, it indicates the diameter of the circle, if it is elliptical, it indicates the minor axis of the ellipse, and if it is rectangular, it indicates the length of the short side of the rectangle.
  • the opening shape of the hole is not particularly limited, and may be a round shape, an elliptical shape, a square shape, a rectangular shape, a hexagonal shape or the like!
  • the method for producing the polymer film having the her-cam structure is not particularly limited. To do this, for example, an organic solvent solution of resin is cast on a substrate, and the organic solvent is evaporated and condensation occurs on the cast liquid surface. A method of evaporating the minute water droplets after forming a porous structure is mentioned.
  • the material of the cover member 30 may be a knitted fabric, for example, stockings, in addition to the Herkam film.
  • a knitted fabric such as stockings
  • the thickness is not too thick and can be stretched, so that the bending rigidity in the major axis direction and the rigidity in the radial direction can be suppressed.
  • the covered stent 10 made of knitted fabric can follow the movement and bending of the body lumen. Therefore, the function can be performed stably without deviating from the positional force where the covered stent 10 is placed.
  • the covered stent 10 according to the embodiment of the present invention is manufactured by winding the cover material 30 around the outer peripheral portion of the stent 20. A specific manufacturing method will be described in detail later.
  • the covered stent 10 includes the radial rigidity and the long-axis bending of the covered stent with respect to the radial rigidity and the long-axis bending rigidity of the stent 20, respectively.
  • the stiffness ratio is specified. That is, assuming that the radial stiffness of the stent 20 is Rfs, the bending stiffness in the long axis direction is Afs, the radial stiffness of the covered stent 10 is Rfc, and the bending stiffness in the long axis direction is Afc, Rfc / Rfs ⁇ l 5 and AfcZAfs ⁇ 2.0. Further, the cover material 30 is used by being stretched by 1.2 to 3.0 times along the circumferential direction of the stent 20 in the expanded state of the stent 20.
  • RfcZRfs exceeds 1.5, the rigidity in the radial direction of the covered stent 10 is increased, and stimulation to the body lumen wall is increased, which is not preferable. Also, if the value of AfcZAfs exceeds 2.0, the bending stiffness of the covered stent 10 in the long axis direction becomes high and follows the bending of the body lumen, which is not preferable. Furthermore, when the cover material 30 is stretched by 1.2 to 3.0 times along the circumferential direction of the stent 20 in the expanded state of the stent 20, the cover material 30 is stretched by less than 1.2 times.
  • the cover material 30 does not sufficiently adhere to the stent 20 and the cover material 30 may be peeled off in the body lumen.
  • the cover member 30 is stretched by 3.0 times or more, the cover member 30 is sufficiently tightly attached to the stent 20 and the cover member 30 is stretched to a specified value or more, so that the bending rigidity is increased. Therefore, it is preferable that the covered stent 10 according to the embodiment of the present invention is manufactured with the rigidity defined above, and the cover member 30 is manufactured within the range of the stretching ratio defined above.
  • the covered stent of the present invention can flexibly follow the movement and bending of the body lumen even when it is placed in the body lumen.
  • FIG. 2 (a) is a schematic view showing a method for producing the covered stent 10 of the present invention.
  • the method for manufacturing the covered stent 10 according to the embodiment of the present invention is as follows. First, the stent 20 has a stent diameter-reducing step (first diameter-reducing step) S1 for reducing the diameter of the stent 20 until the outer diameter force becomes 1/3 to 2/3. Next, in this state, there is a cover material coating step S2 for covering the cover material 30 having a size corresponding to one round of the outer diameter in the reduced diameter state.
  • first diameter-reducing step for reducing the diameter of the stent 20 until the outer diameter force becomes 1/3 to 2/3.
  • cover material coating step S2 for covering the cover material 30 having a size corresponding to one round of the outer diameter in the reduced diameter state.
  • the covered stent 10 wound with the cover material 30 is further reduced in diameter so as to be inserted into an inner lumen such as the outer tube (sheath) 101 of the stent delivery force tater shown in FIG. (Second diameter reduction step) S3 is included.
  • the size of the cover material is not limited to the outer diameter of the stent in a reduced diameter state, and a plurality of outer diameters of the stent in a reduced diameter may be included in one circle. You may wind around.
  • the cover material 95 is wound around the stent 99 as shown in FIG. 2 (b).
  • the stent 99 had a step S10 in which the diameter of the stent 99 was not reduced (in the diameter-expanded state), and the cover material 95 having a size corresponding to one circumference was wound around the outer periphery.
  • the covered stent of the present invention is a cover having a size corresponding to one round after the diameter of the stent is reduced until the outer diameter of the stent becomes 1Z3 to 2Z3. Wrap the material.
  • the cover material 30 is stretched by the stent 20 and the stent 20 and the cover material 30 are brought into close contact with each other.
  • the stent 20 and the cover material 30 can be integrated together without using an adhesive. Therefore, the cover material 30 does not cling to the stent 20 due to movement or bending of the body lumen when it is placed in the body lumen.
  • the rigidity of the covered stent can be kept low. Even if the covered stent 10 is placed in the body lumen, the covered stent 10 is placed by the movement or bending of the body lumen. Positional force Deviation can be prevented.
  • the conventional covered stent was covered / covered without being reduced in diameter, so that the remaining cover material was folded when the diameter was reduced in the manufacturing process. This allows the folding force Due to the large amount of the bar material, there is a problem that it becomes bulky and it is difficult to enter a sheath with a small diameter (see FIG. 5) used for stent placement. For this reason, the folded cover materials are sticking to each other, and the diameter of the covered stent tends to be hindered. There was also a problem that could not be done.
  • the cover material when the outer diameter of the stent is reduced and then the cover material is wound, the cover material may be loosened when the diameter is further reduced for insertion into the sheath. And the covered stent can be easily placed in the body lumen.
  • the stent described in Patent Document 1 (hereinafter referred to as “Type A”) was used as the stent.
  • a covered stent test piece was prepared using the above-mentioned Hercam film described in International Publication WO2005Z051450 (hereinafter, simply referred to as “No. 2 cam film”) as the force bar material.
  • the No-Cam membrane was cast in a glass petri dish with a diameter of 20 cm in diameter using a 3 mg / mL chloroform solution of 1,2-polybutadiene (trade name: manufactured by RB820 JSR). It was prepared by volatilizing the black mouth form.
  • the obtained elastic cam film had an initial elastic modulus of 46 kPa.
  • the initial elastic modulus was measured using a RHEO METER (NRM-2002J, manufactured by Fudo Kogyo Co., Ltd.) at a tensile speed of 20 mmZmin with a test piece having a distance of 10 mm between the chuck 150 and 150 (see FIG. 4).
  • the initial elastic modulus is the slope of the approximate curve of the tensile strength curve (horizontal axis: elongation (mm), vertical axis: tensile load (N)) from 0 to 15% elongation, and the cross-sectional area of the tensile specimen. The value divided by.
  • the outer diameter of the stent was first reduced to a size of 5 mm.
  • the cover material was wound eight times with the size of one round of the stent in the reduced state as a single stroke, and further reduced in diameter to produce a cannulated stent.
  • the circumferential dimension in the expanded state was measured.
  • the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured.
  • the circumferential dimension in the expanded state was 28 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 22 mm. Therefore, the draw ratio was 1.3.
  • the diameter expansion rate of the covered stent was 99%.
  • a knitted fabric, here stockings manufactured by Danze Co., Ltd., rsoft fit No. SM-93SJ (material: nylon, polyurethane), approximately 200 / z m thickness) was used as the cover material.
  • a covered stent was produced in the same manner as in Example 1 except that the number of times of covering of the cover material was one.
  • the initial elastic modulus of the knitted fabric constituting the covered stent was 1.2 kPa.
  • the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 27 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 16 mm. Therefore, the draw ratio was 1.7. The diameter expansion rate of the covered stent was 96%.
  • a covered stent was produced in the same manner as in Example 1 except that the stent described in Patent Document 2 (hereinafter referred to as “TypeB ⁇ ”) was used as the stent.
  • the dimension in the circumferential direction in the expanded diameter state was measured.
  • the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured.
  • the circumferential dimension in the expanded state was 27 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 20 mm. Therefore, the draw ratio was 1.4.
  • the diameter expansion rate of the covered stent was 96%.
  • Cover material knitted fabric, stockings (manufactured by Danze Co., Ltd., rsoft fit No. SM -93SJ (material: nylon, polyurethane), about 200 / zm thick) was used.
  • a covered stent was produced in the same manner as in Example 3 except that the number of times of covering of the cover material was one.
  • the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 28 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 16 mm. Therefore, the draw ratio was 1.8 times. The diameter expansion rate of the covered stent was 99%.
  • a covered stent was produced in the same manner as in Example 1 except that the outer diameter of the stent was reduced to 3 mm.
  • the dimension in the circumferential direction in the expanded diameter state was measured.
  • the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured.
  • the circumferential dimension in the expanded state was 22 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 13 mm. Therefore, the draw ratio was 1.7 times.
  • the diameter expansion rate of the covered stent was 70%.
  • a covered stent was produced in the same manner as in Example 4 except that the outer diameter of the stent was reduced to 3 mm.
  • the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 27 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 14 mm. Therefore, the draw ratio was 1.9 times. The diameter expansion rate of the covered stent was 93%.
  • a covered stent was produced in the same manner as in Example 1.
  • the flat membrane constituting this covered stent was cast in a glass petri dish having a diameter of 15 cm with a 7.8 mg ZmL chloroform solution of 1,2-polybutadiene (trade name: manufactured by RB820 JSR). This can be obtained by volatilizing chlorophenol in a draft.
  • the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the dimension in the circumferential direction in the expanded state was 24 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 20 mm. Therefore, the draw ratio was 1.2 times. The diameter expansion rate of the covered stent was 83%.
  • Table 1 shows the measurement results in Examples 1 to 6 and Comparative Example 1 described above.
  • Rfc / Rfs which is the ratio of the radial stiffness of the covered stent to the stent
  • AfcZAfs which is the ratio of the rigidity of the covered stent to the stent in the long axis direction, was 2.0 or less, which also satisfied the specified value of the present invention.
  • the Rfc force which is the ratio of the radial stiffness of the covered stent, is 15 N or less
  • the Afc force which is the ratio of the rigidity in the long axis direction of the covered stent, is 0. 3N or less.
  • the wound diameter of the stent was 5 mm, and the draw ratio of the cover material was 1.3 to 1.8 times.
  • the wound diameter of the stent was 3 mm, and the draw ratio of the cover material was 1.7 to 1.9 times.
  • the range of the stretch ratio of the cover material of the present invention is satisfied, so that even if it is placed in the body lumen, it functions stably at a predetermined position without stimulating the body. I was able to demonstrate what I could do.
  • Comparative Example 1 is not suitable as the covered stent of the present invention because Rfc, which is the rigidity in the radial direction of the covered stent, is larger than 15N and does not satisfy the specified value of the present invention.

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Abstract

A covered stent friendly to living body tissue, in which a cover member presses itself against a stent body without the use of an adhesive agent and does not peel off from it, that causes a body lumen wall less irritations, that follows curves of the body lumen, and, even after indwelled in the body, that stably exhibits its function at the indwelled position, and a method of producing the covered stent. The covered stent (10) has a tubular stent (20) and a cover member (30) provided over the outer periphery of the stent and is used as indwelled in a body lumen. The covered stent satisfies the relationships of Rfc/Rfs ≤ 1.5 and Afc/Afs ≤ 2.0, with Rfs being the radial rigidity of the stent (20), Afs being the bending rigidity in the longitudinal axis direction of the stent (20), Rfc being the radial rigidity of the covered stent (10), and Afc being the bending rigidity in the longitudinal axis direction of the covered stent (10). Also, to use the cover member (30), it is extended in length by 1.2 to 3.0 times the original length with the stent (20) expanded in diameter, where the extension is along the circumferential direction of the stent (20).

Description

明 細 書  Specification
カバードステントおよびカバードステントの製造方法  Covered stent and method for manufacturing covered stent
技術分野  Technical field
[0001] 本発明は、胆管、血管、気管、食道および尿道などの体内管腔に狭窄部が生じた 場合に、体内管腔の確保を目的として、狭窄部を拡張するために好適に用いられる カバードステント、およびカバードステントの製造方法に関する。  [0001] The present invention is suitably used to expand a stenosis for the purpose of securing a body lumen when a stenosis occurs in a body lumen such as a bile duct, blood vessel, trachea, esophagus and urethra. The present invention relates to a covered stent and a method for manufacturing the covered stent.
背景技術  Background art
[0002] 胆管、血管、気管、食道および尿道などの体内管腔に腫瘍組織が形成されて、体 内管腔に狭窄部が生じた場合には、その狭窄部にステントを留置して、体内管腔を 確保する治療法が利用されている。ステントは、一般的に、金属線を網目状に形成し た円筒状の部材であり、径方向への伸縮が可能である。この治療法によれば、ステン ト 102を、外径を収縮させた状態で、例えば、図 5に示すようなデリバリーカテーテル 100により体内管腔に挿入して狭窄部に留置させる。そして、この留置位置でステン ト 102の外径を拡張させて、狭窄部の管腔を確保することができる。なお、図 5中、 10 1はデリバリーカテーテルの外管（シース）を、 103は内管を、そして 104は先端チッ プをそれぞれ示している。  [0002] When a tumor tissue is formed in a body lumen such as the bile duct, blood vessel, trachea, esophagus and urethra and a stenosis occurs in the body lumen, a stent is placed in the stenosis, Therapies that secure the lumen are used. A stent is generally a cylindrical member in which metal wires are formed in a mesh shape, and can expand and contract in the radial direction. According to this treatment method, the stent 102 is inserted into a body lumen by a delivery catheter 100 as shown in FIG. 5, for example, with the outer diameter contracted, and placed in a stenosis. Then, the outer diameter of the stent 102 can be expanded at this indwelling position to secure the lumen of the stenosis. In FIG. 5, 101 indicates an outer tube (sheath) of the delivery catheter, 103 indicates an inner tube, and 104 indicates a tip.
[0003] しかし、ステントは、金属線を網目状に形成した部材であるため、ステントを構成す る線材の隙間部分から、ステントの内側に腫瘍組織などが入り込むように成長して、 狭窄の早期再発が懸念される場合があった。このため、ステントの外周部分に榭脂 製のカバー材を設けることにより、腫瘍組織の入り込みを防いで狭窄の早期再発を 抑えることができ、かつ体内管腔への腫瘍組織等の成長を抑えることが可能なカバ 一ドステントも利用されて 、る。  However, since a stent is a member in which a metal wire is formed in a mesh shape, it grows so that a tumor tissue or the like enters the inside of the stent from the gap portion of the wire constituting the stent, so that the early stage of stenosis There was a concern about recurrence. For this reason, by providing a cover material made of a resin on the outer periphery of the stent, it is possible to prevent the invasion of tumor tissue, to suppress early recurrence of stenosis, and to suppress the growth of tumor tissue etc. in the body lumen. Coverable stents are also available.
[0004] 特許文献 1には、周方向に連続して形成されたジグザグ形状の線材によって構成さ れ、半径方向に収縮状態力 拡張が可能なリング形状のステント単位と、このステント 単位を構成する線材のジグザグ形状の折り返し端部のうち少なくとも一つと、当該ス テント単位に軸方向に隣接する別のステント単位における線材のジグザグ形状の少 なくとも一つの折り返し端部とを連結することにより形成されるステント、およびステント の外周にカバーフィルムが巻かれたカバードステントが開示されて!、る。この形状を 持つことにより、特許文献 1に係るステントは、収縮状態における可撓性に優れ、体内 管腔に容易に挿入することができ、拡径状態を維持しやすくすることができる。加えて 、体内管腔の内壁や、ステントの外周に巻かれたカバーフィルムを損傷するおそれを /J、さくすることちできる。 [0004] Patent Document 1 includes a ring-shaped stent unit configured by a zigzag-shaped wire continuously formed in the circumferential direction and capable of expanding a contracted state force in the radial direction, and configures this stent unit. It is formed by connecting at least one of the zigzag folded ends of the wire and at least one folded end of the zigzag of the wire in another stent unit axially adjacent to the stent unit. Stent, and stent A covered stent is disclosed in which a cover film is wound around the outer periphery! By having this shape, the stent according to Patent Document 1 has excellent flexibility in a contracted state, can be easily inserted into a body lumen, and can easily maintain an expanded state. In addition, the risk of damaging the inner wall of the body lumen and the cover film wound around the outer periphery of the stent can be reduced.
[0005] また、特許文献 2には、管壁部が非膨張状態力も膨張状態まで移行しうるウェブ構 造を持ったチューブ状可撓性本体を備えるステントが開示されて 、る。このウェブ構 造は、そのパターンにおいて、各ウェブが互いに角度を持って配置された 3つの部分 を備えているため、ステントの膨張の際にその収縮を最小化させ、非膨張状態では 極めて可撓性に優れている。さらには膨張状態では極めて安定な構造をとることがで きる。  [0005] Further, Patent Document 2 discloses a stent including a tube-shaped flexible body having a web structure in which a tube wall portion can transfer a non-expanded state force to an expanded state. This web structure has three parts in the pattern where each web is positioned at an angle to each other, thus minimizing its contraction when the stent is expanded and extremely flexible in the unexpanded state. Excellent in properties. Furthermore, it can have a very stable structure in the expanded state.
特許文献 1：国際公開公報 WO2006Z001367号公報  Patent Document 1: International Publication No. WO2006Z001367
特許文献 2 :特表 2002— 524135号公報  Patent Document 2: Japanese Translation of Special Publication 2002-524135
発明の開示  Disclosure of the invention
発明が解決しょうとする課題  Problems to be solved by the invention
[0006] このような従来のカバードステントのカバー材は、裸状のステントを榭脂溶液にディ ップする方法や、榭脂のフィルムを裸状のステントに卷 ヽて接着剤などで接着させる 方法で、ステント本体とカバー材とが剥がれな 、ように作られてきた。  [0006] Such a conventional covered stent cover material includes a method of dipping a bare stent into a resin solution, or a film of a resin coated on a bare stent and bonded with an adhesive or the like. In this way, the stent body and the cover material have not been peeled off.
[0007] しかし、従来のカバードステントは、ディップ法により製造すると、カバー膜が非常に 肉厚になってしまう。また、榭脂のフィルムを接着剤などで接着させる方法により製造 すると、接着剤が固まった部分は非常に硬くなつてしまうため、体内管腔の動きや屈 曲に追従できずにカバードステントが留置位置力 逸脱してしまう場合や、径方向の 剛性が高すぎて生体組織を刺激してしまう場合、さらにはカバードステント留置による 合併症を引き起こす場合があった。  However, when a conventional covered stent is manufactured by the dip method, the cover film becomes very thick. In addition, if the film of the resin is bonded by an adhesive, the part where the adhesive has hardened becomes very hard, so the covered stent cannot be placed without following the movement and bending of the body lumen. When the position force deviates, or when the radial stiffness is too high to irritate the living tissue, complications may occur due to the placement of the covered stent.
[0008] また、従来のカバードステントは、ステントを縮径せずにカバー材を被覆して 、たた め、製造過程で縮径した際に余ったカバー材は折りたたまれていた。しかし、その折 りたたまれるカバー材の量が多いため、嵩高くなり、ステントの留置に用いられる径の 小さなシースに入りにくいという問題があった。この他にも、ステントを縮径せずにカバ ー材を被覆して、縮径した際に余ったカバー材は折りたたまれていたため、折りたた まれたカバー材が互いにくつついて、カバードステントの拡径阻害が生じやすくなつ ていた。これにより、デリバリーカテーテルなどにより体内管腔にカバードステントを挿 入する際に、カバードステントを容易に留置できな 、と 、う問題もあった。 [0008] Further, in the conventional covered stent, the cover material is covered without reducing the diameter of the stent, and therefore, the remaining cover material when the diameter is reduced in the manufacturing process is folded. However, since the amount of the cover material that can be folded is large, the cover material is bulky, and there is a problem that it is difficult to enter a sheath having a small diameter used for stent placement. In addition, the cover can be covered without reducing the diameter. When the cover material was covered and the diameter of the cover material was reduced, the remaining cover material was folded, so that the folded cover materials were sticking to each other, and the diameter expansion of the covered stent was likely to occur. As a result, when the covered stent is inserted into the body lumen using a delivery catheter or the like, there is also a problem that the covered stent cannot be easily placed.
[0009] そこで、本発明は、前記諸点に鑑みてなされたものである。本発明の目的は、接着 剤を用いずともステント本体にカバー部材が抱き付 、て剥がれな!/、だけでなぐ体内 管腔壁への刺激が少なぐ体内管腔の屈曲に追従でき、留置後もその位置で安定 的に機能が発揮できるカバードステント、およびその製造方法を提供することにある。  Therefore, the present invention has been made in view of the above points. The object of the present invention is to hold the cover member on the stent body without using an adhesive, and to peel off! /, Which can follow the bending of the body lumen with less irritation to the body lumen wall. It is another object of the present invention to provide a covered stent that can function stably at that position and a manufacturing method thereof.
[0010] 以下、本発明について説明する。なお、本発明の理解を容易にするために添付図 面の参照符号を括弧書きにて付記するが、それにより本発明が図示の形態に限定さ れるものではない。  [0010] Hereinafter, the present invention will be described. In order to facilitate understanding of the present invention, reference numerals in the attached drawings are appended in parentheses, but the present invention is not limited to the illustrated form.
[0011] 本発明のカバードステント（10)は、筒状のステント（20)と、このステントの外周部分 に設けられて 、るカバー材 (30)とを備え、体内管腔に留置して用いられるカバード ステントであって、ステントの径方向の剛性を Rfs、ステントの長軸方向の曲げ剛性を Afs、当該カバードステントの径方向の剛性を Rfc、当該カバードステントの長軸方向 の曲げ剛性を Afcとしたとき、 RfcZRfs≤l . 5で、かつ AfcZAfs≤2. 0の関係を満 たし、カバー材は、ステントの拡径状態で、ステントの円周方向に沿って 1. 2〜3. 0 倍に延伸されることを特徴とする。  [0011] The covered stent (10) of the present invention includes a cylindrical stent (20) and a cover material (30) provided on an outer peripheral portion of the stent, and is used by being placed in a body lumen. The covered stent is a radial stiffness of the stent, Rfs, the bending stiffness of the stent in the long axis direction is Afs, the radial stiffness of the covered stent is Rfc, and the bending stiffness of the covered stent in the long axis direction is Afc. RfcZRfs≤l.5 and AfcZAfs≤2.0, and the cover material is 1.2 to 3.0 along the circumferential direction of the stent in the expanded state of the stent. The film is stretched twice.
[0012] ステントおよびカバードステントの径方向の剛性 (Rfs、Rfc)の測定は、 MSI Radi al Expansion Force Gage RX500— 01 (MSI製）を用い、 37°Cの雰囲気下で おこなうことができる。これによれば、ステントおよびカバードステントの径方向の全周 を均等に縮径および拡径することで、反発力を測定できる。長軸方向の曲げ剛性 (A fs、 Afc)の測定方法を、図 3に示す。まずステント 130もしくはカバードステント 131 の内側管腔に、ステント 130もしくはカバードステント 131の内径とほぼ等し 、外径の 芯棒 133を挿入して垂直に固定する。その際、ステント 130もしくはカバードステント 1 31と芯棒 133が重ならない部分力 長軸方向に長さ 20mmとなるように芯棒 133を 挿入する。そしてステント 130もしくはカバードステント 131に挿入された側の芯棒 13 3の端 135と面位置をあわせて万力で固定する。次に、芯棒 133と重なっていない部 分のステント 130もしくはカバードステント 131の、ステント 130もしくはカバードステン ト 131に挿入された側の芯棒 133の端 136からの距離が 20mmの位置をフォースゲ ージ 138で押して、長軸方向とのなす角が 60° となるように屈曲させた時の反発力 を測定する。これらは 37°C雰囲気下でフォースゲージ 138を用いておこなう。 [0012] The radial stiffness (Rfs, Rfc) of the stent and the covered stent can be measured using an MSI Radial Expansion Force Gage RX500-01 (manufactured by MSI) in an atmosphere of 37 ° C. According to this, the repulsive force can be measured by uniformly reducing and expanding the entire circumference in the radial direction of the stent and the covered stent. Figure 3 shows how to measure the bending stiffness (A fs, Afc) in the major axis direction. First, a core rod 133 having an outer diameter substantially equal to the inner diameter of the stent 130 or the covered stent 131 is inserted into the inner lumen of the stent 130 or the covered stent 131 and fixed vertically. At that time, the core rod 133 is inserted so that the partial force in which the stent 130 or the covered stent 131 and the core rod 133 do not overlap each other is 20 mm in the lengthwise direction. Then, the end 135 of the core rod 133 on the side inserted into the stent 130 or the covered stent 131 is aligned with the surface position and fixed with a vise. Next, the part that does not overlap with the core rod 133 Push the force gauge 138 at the position where the distance from the end 136 of the core rod 133 on the side of the stent 130 or the covered stent 131 of the minute stent 130 or the covered stent 131 to the major axis direction. Measure the repulsive force when bent so that the angle is 60 °. These are performed using a force gauge 138 in an atmosphere of 37 ° C.
[0013] カバー材の延伸倍率 Mcは、下記式、 [0013] The draw ratio Mc of the cover material is the following formula:
Mc= (拡径状態にあるカバードステントの円周方向の長さ） Z (未延伸状態にある カバー材の円周方向の長さ）  Mc = (the length in the circumferential direction of the covered stent in the expanded state) Z (the length in the circumferential direction of the cover material in the unstretched state)
で求めることができる。具体的には、まず、拡径状態にあるカバードステントの円周方 向の長さを測定する。次に、拡径状態にあるカバードステントから、その長軸方向に 沿ってカバー材を切断してステントからカバー材を剥がし取る。このようにして、応力 が取り除かれた未延伸状態にあるカバー材の円周方向の長さを測定する。これらの 測定結果により、上記式に基づいてカバー材の延伸倍率を特定できる。  Can be obtained. Specifically, first, the length of the covered stent in the expanded state in the circumferential direction is measured. Next, from the covered stent in the expanded diameter state, the cover material is cut along the long axis direction, and the cover material is peeled off from the stent. In this way, the circumferential length of the cover material in an unstretched state from which the stress has been removed is measured. From these measurement results, the draw ratio of the cover material can be specified based on the above formula.
[0014] カバー材は、ステントの拡径状態で、ステントの円周方向に沿って 1. 2〜3. 0倍に 延伸されており、 1. 2〜2. 5倍に延伸されていることがより好ましい。  [0014] The cover material is stretched 1.2 to 3.0 times along the circumferential direction of the stent in the expanded state of the stent, and 1.2 to 2.5 times. Is more preferable.
[0015] 本発明のカバードステントは、拡径した際に、その拡径率が 80%を超え、 90%以 上であることが好ましい。ここで「拡径率」とは、（カバードステントの外径 Zステントの 外径） X 100で求められる値のことである。前記拡径率が上記範囲となることにより、 ステント本体力 カバー材が脱落するのを防止できるとともに、カバードステントが胆 管から逸脱するのを防止できる。さら〖こ、前記拡径率が上記範囲となることにより、狭 窄部を十分に拡げることができて、カバードステント本来の機能、すなわち、十分な内 腔の確保をすることができるという機能を奏することができ、ひいては、管腔の開存期 間を長くすることができる。  [0015] When the diameter of the covered stent of the present invention is expanded, the diameter expansion rate is preferably more than 80% and more than 90%. Here, the “expansion ratio” is a value obtained by (outer diameter of covered stent Z outer diameter of stent) X 100. When the diameter expansion rate falls within the above range, the stent body force cover material can be prevented from falling off, and the covered stent can be prevented from deviating from the bile duct. Furthermore, when the diameter expansion ratio is in the above range, the narrowed portion can be sufficiently expanded, and the function of the covered stent, that is, the function of ensuring a sufficient lumen. And thus the lumen patency can be lengthened.
[0016] 本発明のカバードステントに用いられるステントにおいて、その構造は、特に限定さ れない。例えば、特許文献 1および 2で開示されたステントのように、本発明に用いら れるステントは、金属線の網目にできる隙間がある程度狭ぐカバー材が腫瘍組織な どの圧迫により網目の隙間からステント内部に入り込まないような構造を有しているこ とが好ましい。 [0016] The structure of the stent used in the covered stent of the present invention is not particularly limited. For example, like the stents disclosed in Patent Documents 1 and 2, the stent used in the present invention has a cover material in which the gap formed in the metal wire mesh is narrow to some extent. It is preferable to have a structure that does not enter the inside.
[0017] 本発明のカバードステント（10)において、カバー材（30)は、その初期弾性率が 50 kPa以下であることが好ましい。このような構成によれば、 AfcZAfsの値を小さく保 つことができ、これにより、体内管腔への留置をより一層容易にできるとともに、当該 位置に一層安定して留置させることができる。 [0017] In the covered stent (10) of the present invention, the cover material (30) has an initial elastic modulus of 50. It is preferably kPa or less. According to such a configuration, it is possible to keep the value of AfcZAfs small, and thereby it is possible to more easily place in the body lumen, and to place more stably at the position.
[0018] 「初期弾性率」とは、カバー材の弾性率のうち、最初に測定される値のことをいう。初 期弾性率は、カバー材の両端をクリップのようなもので留め、これを一直線状で相反 する方向へ引っ張ることにより測定する。 [0018] "Initial elastic modulus" refers to the value measured first among the elastic modulus of the cover material. The initial elastic modulus is measured by holding the cover material at both ends with a clip and pulling it in the opposite direction.
[0019] 本発明のカバードステント（10)において、カバードステントの径方向の剛性 Rfcと、 ステントの長軸方向の曲げ剛性 Afcとの関係力 30≤RfcZAfc≤ 100となることが 好ましい。 [0019] In the covered stent (10) of the present invention, it is preferable that the relational force between the radial rigidity Rfc of the covered stent and the bending rigidity Afc of the long axis of the stent is 30≤RfcZAfc≤100.
[0020] 本発明のカバードステント（10)において、カバー材（30)は、ハ-カム膜からなるこ とが好ましい。このような構成によれば、カバー材の柔軟性が高ぐカバードステント の長軸方向の曲げ剛性 Afcの値を小さくできると 、う効果がある。  [0020] In the covered stent (10) of the present invention, it is preferable that the cover material (30) is made of a hard cam membrane. According to such a configuration, it is possible to reduce the value of the bending rigidity Afc in the major axis direction of the covered stent in which the flexibility of the cover material is high.
[0021] 「ハ-カム膜」とは、ハ-カム構造を有した高分子フィルムのことを 、 、、 ノ、二カム構 造とは、孔径がほぼ一定の複数の孔が規則正しく配列してなる多孔構造を意味する 。なお、前記孔は、ハニカム膜の一方の面力 反対側の他方の面へ貫通していても よいし、非貫通であってもよい。ノ、二カム構造は、高分子フィルムの構造が蜂の巣の ように、無数の小さな穴がフィルム上に整然と空いている構造を持っていればよぐ必 ずしも六角形の構造が連続的に展開している構造である必要はない。  [0021] "Her cam membrane" refers to a polymer film having a her cam structure, and in the two cam structure, a plurality of holes having a substantially constant hole diameter are regularly arranged. Means a porous structure. In addition, the hole may penetrate through the other surface on the opposite side of the surface force of the honeycomb film, or may not penetrate. The two-cam structure has a hexagonal structure continuously if the polymer film has a structure in which numerous small holes are regularly arranged on the film, such as a honeycomb. It does not have to be a deployed structure.
[0022] 本発明のカバードステント（10)において、カバー材（30)は、編物であってもよい。  [0022] In the covered stent (10) of the present invention, the cover material (30) may be a knitted fabric.
このような構成によれば、 AfcZAfsの値を小さくできるという効果がある。  Such a configuration has the effect of reducing the value of AfcZAfs.
[0023] 「編物」の種類は特に限定されないが、例えばストッキングのような編物力 厚みが 少なぐ伸縮自在であり、かつステントを縮小したときに折りたたんでも互いにくつっき にくいため、好ましい。  [0023] The type of "knitted fabric" is not particularly limited, but it is preferable because, for example, a knitted fabric force such as stockings is thin and stretchable, and it is difficult to stick to each other even when folded when the stent is contracted.
[0024] 本発明のカバードステント（10)において、カバードステントは、その径方向の剛性 Rfcが 15N以下で、かつその長軸方向の曲げ剛性 Afcが 0. 3N以下であることが好 ま 、。このような構成によれば体内管腔組織壁への刺激が少な 、と 、う効果がある  [0024] In the covered stent (10) of the present invention, the covered stent preferably has a radial rigidity Rfc of 15 N or less and a bending rigidity Afc in the major axis direction of 0.3 N or less. According to such a configuration, there is little effect on the luminal tissue wall in the body, and there is an effect.
[0025] 一方、筒状のステント（20)と、このステントの外周部分に設けられるカバー材（30) とを備え、体内管腔に留置して用いられる本発明の力バーステント（10)の製造方法 は、ステントを、その外径が 1Z3〜2Z3の寸法になるまで縮径させるステント縮径ェ 程と、縮径したステントの外周部分にカバー材を被覆させるカバー材被覆工程と、を 備えることを特徴とする。 [0025] On the other hand, a cylindrical stent (20) and a cover material (30) provided on the outer periphery of the stent The method of manufacturing the force bar stent (10) of the present invention used by being placed in a body lumen is a stent diameter reduction process in which the stent is reduced in diameter until the outer diameter becomes 1Z3 to 2Z3. And a cover material coating step of covering the outer peripheral portion of the reduced diameter stent with a cover material.
発明の効果  The invention's effect
[0026] 本発明のカバードステントによれば、長軸方向の曲げ剛性と、径方向の剛性を適正 な範囲とすることにより、体内管腔への留置を容易にできるとともに、留置後もその位 置で安定的に体内管腔を確保する機能を奏することができる。  [0026] According to the covered stent of the present invention, by placing the bending rigidity in the major axis direction and the rigidity in the radial direction within appropriate ranges, the placement in the body lumen can be facilitated, and the position can be maintained after the placement. It is possible to provide a function of stably securing the body lumen in the position.
[0027] また、本発明のカバードステントの製造方法によれば、ステントを所定の寸法まで縮 径させた後、そのステントの外周部分にカバー材を被覆させることにより、接着剤等を 用いることなくステントにカバー材を抱き付かせることができる。このため、体内管腔へ の留置を容易にできるとともに、合併症等の発生のおそれを抑えることができる。 図面の簡単な説明  [0027] Further, according to the method for manufacturing a covered stent of the present invention, the diameter of the stent is reduced to a predetermined size, and then the outer peripheral portion of the stent is covered with a cover material without using an adhesive or the like. The cover material can be hugged to the stent. For this reason, indwelling in a body lumen can be facilitated, and the risk of occurrence of complications can be suppressed. Brief Description of Drawings
[0028] [図 1]本発明の実施形態に係るカバードステントを示す斜視図である。 FIG. 1 is a perspective view showing a covered stent according to an embodiment of the present invention.
[図 2]本発明の実施形態に係るカバードステントの製造方法を含む概略図である。  FIG. 2 is a schematic view including a method for manufacturing a covered stent according to an embodiment of the present invention.
[図 3]ステントおよびカバードステントの長軸方向の曲げ剛性 Afsおよび Afcの測定方 法を示す概略図である。  FIG. 3 is a schematic diagram showing a method for measuring bending stiffness Afs and Afc in the major axis direction of a stent and a covered stent.
圆 4]初期弾性率の測定装置を示す概略図である。  IV] Schematic diagram showing a device for measuring the initial elastic modulus.
[図 5]ステントを装着した状態のステントデリバリーカテーテルを示す平面図である。 符号の説明  FIG. 5 is a plan view showing a stent delivery catheter with a stent mounted thereon. Explanation of symbols
[0029] 10 カバードステント [0029] 10 covered stent
20 ステント  20 Stent
30 カバー材  30 Cover material
発明を実施するための最良の形態  BEST MODE FOR CARRYING OUT THE INVENTION
[0030] 本発明の上記した作用及び利得は、次に説明する発明を実施するための最良の 形態から明らかにされる。 [0030] The above-described operation and gain of the present invention will become apparent from the best mode for carrying out the invention described below.
[0031] 以下、本発明を図面に示す実施形態に基づき説明する。 [0032] 図 1は、本発明の実施形態に係るカバードステントを示す斜視図である。本発明の 実施形態に係るカバードステント 10は、筒状のステント 20と、ステント 20の外周部分 に設けられているカバー材 30とを備えている。カバードステント 10では、ステント 20 の径方向の剛性を Rfs、ステント 20の長軸方向の曲げ剛性を Afsとし、カバードステ ント 10の径方向の剛性を Rfc、カバードステント 10の長軸方向の曲げ剛性を Afcとし たとき、 Rfc/Rfs≤l. 5で、かつ AfcZAfs≤2. 0を満たしている。また、カバー材 3 0は、ステント 20の拡径状態で、ステント 20の円周方向に沿って 1. 2〜3. 0倍に延 伸されて用いられる。 Hereinafter, the present invention will be described based on embodiments shown in the drawings. FIG. 1 is a perspective view showing a covered stent according to an embodiment of the present invention. The covered stent 10 according to the embodiment of the present invention includes a cylindrical stent 20 and a cover member 30 provided on the outer peripheral portion of the stent 20. In the covered stent 10, the radial stiffness of the stent 20 is Rfs, the bending stiffness in the major axis direction of the stent 20 is Afs, the radial stiffness of the covered stent 10 is Rfc, and the bending stiffness in the major axis direction of the covered stent 10 is When Afc, Rfc / Rfs≤l.5 and AfcZAfs≤2.0 are satisfied. Further, the cover member 30 is used while being expanded by 1.2 to 3.0 times along the circumferential direction of the stent 20 in the expanded state of the stent 20.
[0033] (ステント）  [0033] (Stent)
本発明の実施形態に係るカバードステントに用いられるステントは、その構造にお いて、特に限定されない。その中でも、前記ステントは、金属線の網目にできる隙間 力 Sある程度狭ぐカバー材が腫瘍組織などの圧迫により網目の隙間からステント内部 に入り込まないような構造を有していることが好ましい。具体的には、前記ステントは、 例えば、特許文献 1に記載のステントのように、周方向に連続して形成されたジグザ グ形状の線材によって構成され、半径方向に収縮状態力 拡張が可能なリング形状 のステント単位と、このステント単位を構成する線材のジグザグ形状の折り返し端部の うち少なくとも一つと、当該ステント単位に軸方向に隣接する別のステント単位におけ る線材のジグザグ形状の少なくとも一つの折り返し端部とを連結することにより形成さ れるステントであることが好ましい。また、この他にも、前記ステントは、特許文献 2に 記載のステントのように、管壁部が非膨張状態力も膨張状態まで移行しうるウェブ構 造を持ったチューブ状可撓性本体を備えるステントであることが好ま 、。このウェブ 構造は、そのパターンにおいて、各ウェブが互いに角度を持って配置された 3つの部 分を備えて 、るようなステントであることが好ま 、。  The stent used for the covered stent according to the embodiment of the present invention is not particularly limited in its structure. Among them, it is preferable that the stent has a structure in which the cover material narrowed to some extent by the mesh of the metal wire S does not enter the inside of the stent through the mesh space due to compression of the tumor tissue or the like. Specifically, the stent is configured by a zigzag-shaped wire continuously formed in the circumferential direction, for example, as in the stent described in Patent Document 1, and the contracted state force can be expanded in the radial direction. At least one of the ring-shaped stent unit, the zigzag folded end of the wire constituting the stent unit, and at least one of the zigzag shape of the wire in another stent unit axially adjacent to the stent unit. The stent is preferably formed by connecting two folded ends. In addition to the above, the stent includes a tube-like flexible body having a web structure in which the tube wall portion can transfer the non-expanded state force to the expanded state as in the stent described in Patent Document 2. Preferable to be a stent. The web structure is preferably a stent such that in its pattern, each web has three parts that are arranged at an angle to each other.
[0034] (カバー材）  [0034] (Cover material)
本発明の実施形態に係るカバードステント 10に用いられるカバー材 30は、ステント の拡径状態で、ステントの円周方向に沿って 1. 2〜3. 0倍に延伸されており、 1. 2 〜2. 5倍に延伸されていることが好ましい。  The cover material 30 used for the covered stent 10 according to the embodiment of the present invention is stretched 1.2 to 3.0 times along the circumferential direction of the stent in a diameter-expanded state of the stent. 2. It is preferable that the film is stretched 5 times.
[0035] また、カバー材の初期弾性率が 20kPa以下であることが好ま U、。初期弾性率がこ の規定値よりも大きいと、カバードステント 10の拡径阻害が生じやすくなり、また、長 軸方向の曲げ剛性 Afcが大きくなつてしまうためである。初期弾性率とは、カバー材 の弾性率のうち、最初に測定される値のことをいう。初期弾性率は、カバー材の両端 をクリップのようなもので留め、これを一直線上で相反する方向へ引っ張ることにより 測定する。初期弾性率の具体的な測定方法例は、実施例において詳述する。 [0035] Further, it is preferable that the initial elastic modulus of the cover material is 20 kPa or less. The initial elastic modulus is If the value is larger than the prescribed value, the diameter expansion of the covered stent 10 is liable to occur, and the bending rigidity Afc in the long axis direction is increased. The initial elastic modulus is the value measured first among the elastic modulus of the cover material. The initial elastic modulus is measured by holding both ends of the cover material with a clip and pulling them in opposite directions on a straight line. Examples of specific methods for measuring the initial elastic modulus will be described in detail in Examples.
[0036] カバー材 30の材質は、ハ-カム膜からなることが好まし!/、。ハ-カム膜とは、ハ-カ ム構造を有した高分子フィルムのことをいう。ハ-カム構造とは、孔径がほぼ一定の 複数の孔が規則正しく配列してなる多孔構造を意味する（国際公開公報 WO2005 Z051450号公報参照)。したがって、高分子フィルムの構造が蜂の巣のように、無 数の小さな孔がフィルム上に整然と空 、て 、る構造を持って 、ればよく、必ずしも六 角形の構造が連続的に展開している必要はない。  [0036] The material of the cover material 30 is preferably made of a Hercam film! A “her cam membrane” refers to a polymer film having a harm structure. The Hercam structure means a porous structure in which a plurality of holes having a substantially constant hole diameter are regularly arranged (see International Publication No. WO2005 Z051450). Therefore, it is only necessary that the polymer film has a structure in which innumerable small holes are regularly formed on the film like a honeycomb, and the hexagonal structure is continuously developed. There is no need.
[0037] このハ-カム構造を構成する孔の平均孔径は、 0. 1-100 μ mであることが好まし ぐ 0. 1〜20 1!1でぁることがょり好ましぐ0. 5〜： LO /z mであることがさらに好ましい 。このような平均孔径を有する孔によって多孔構造を構成することにより、がん細胞な どの腫瘍細胞増殖を抑制するのにより優れた作用を有するフィルムを得ることができ る。ここで、孔径とは、孔の開口形状に対する最大内接円の直径を指す。例えば、孔 の開口形状が円形状である場合はその円の直径を指し、楕円形状である場合はそ の楕円の短径を指し、長方形状である場合その長方形の短辺の長さを指す。なお、 孔の開口形状に特に限定はなぐ円形状、楕円形状、正方形状、長方形状、六角形 状などの!/ヽかなる形状であってもよ!/、。  [0037] The average hole diameter of the holes constituting the Hercam structure is preferably 0.1-100 μm, and 0.1-20 1! 1 is preferably 0. 5 ~: More preferably, LO / zm. By forming a porous structure with pores having such an average pore size, it is possible to obtain a film having a more excellent action for suppressing the growth of tumor cells such as cancer cells. Here, the hole diameter refers to the diameter of the maximum inscribed circle with respect to the opening shape of the hole. For example, if the aperture shape is circular, it indicates the diameter of the circle, if it is elliptical, it indicates the minor axis of the ellipse, and if it is rectangular, it indicates the length of the short side of the rectangle. . It should be noted that the opening shape of the hole is not particularly limited, and may be a round shape, an elliptical shape, a square shape, a rectangular shape, a hexagonal shape or the like!
[0038] このハ-カム構造を有した高分子フィルムの作製方法は特に限定されない。これに は、例えば、榭脂の有機溶媒溶液を基板上にキャストし、このうち有機溶媒を蒸散さ せるとともにキャスト液面で結露を起こさせ、この結露により生じた微小水滴を孔の铸 型として多孔構造を形成させた後、この微小水滴を蒸発させる方法が挙げられる。  [0038] The method for producing the polymer film having the her-cam structure is not particularly limited. To do this, for example, an organic solvent solution of resin is cast on a substrate, and the organic solvent is evaporated and condensation occurs on the cast liquid surface. A method of evaporating the minute water droplets after forming a porous structure is mentioned.
[0039] また、カバー材 30の材質は、ハ-カム膜の他にも、編物、例えば、ストッキングのよ うなものであってもよい。ストッキングのような編物であれば、厚さも厚すぎず、また伸 縮自在であるため、長軸方向の曲げ剛性ゃ径方向の剛性を抑えることができる。この ため、編物をカバー材としたカバードステント 10は、体内管腔の動きや屈曲に追従で き、カバードステント 10が留置された位置力も逸脱しないで安定的にその機能を発 揮できる。 [0039] Further, the material of the cover member 30 may be a knitted fabric, for example, stockings, in addition to the Herkam film. In the case of a knitted fabric such as stockings, the thickness is not too thick and can be stretched, so that the bending rigidity in the major axis direction and the rigidity in the radial direction can be suppressed. For this reason, the covered stent 10 made of knitted fabric can follow the movement and bending of the body lumen. Therefore, the function can be performed stably without deviating from the positional force where the covered stent 10 is placed.
[0040] (カバードステント）  [0040] (Covered stent)
本発明の実施形態に係るカバードステント 10は、上記カバー材 30を上記ステント 2 0の外周部分に巻き付けて作製される。具体的な製造方法は、後に詳述する。  The covered stent 10 according to the embodiment of the present invention is manufactured by winding the cover material 30 around the outer peripheral portion of the stent 20. A specific manufacturing method will be described in detail later.
[0041] 本発明の実施形態に係るカバードステント 10は、ステント 20の径方向の剛性およ び長軸方向の曲げ剛性のそれぞれに対する、カバードステントの径方向の剛性およ び長軸方向の曲げ剛性の比率が規定されている。すなわち、ステント 20の径方向の 剛性を Rfs、長軸方向の曲げ剛性を Afsとし、カバードステント 10の径方向の剛性を Rfc、長軸方向の曲げ剛性を Afcとしたとき、 Rfc/Rfs≤l. 5で、かつ AfcZAfs≤ 2. 0である。また、カバー材 30は、ステント 20の拡径状態で、ステント 20の円周方向 に沿って 1. 2〜3. 0倍に延伸されて用いられる。  [0041] The covered stent 10 according to the embodiment of the present invention includes the radial rigidity and the long-axis bending of the covered stent with respect to the radial rigidity and the long-axis bending rigidity of the stent 20, respectively. The stiffness ratio is specified. That is, assuming that the radial stiffness of the stent 20 is Rfs, the bending stiffness in the long axis direction is Afs, the radial stiffness of the covered stent 10 is Rfc, and the bending stiffness in the long axis direction is Afc, Rfc / Rfs≤l 5 and AfcZAfs≤2.0. Further, the cover material 30 is used by being stretched by 1.2 to 3.0 times along the circumferential direction of the stent 20 in the expanded state of the stent 20.
[0042] RfcZRfsの値が 1. 5を超えると、カバードステント 10の径方向の剛性が高くなり、 体内管腔壁への刺激が強くなるため好ましくない。また、 AfcZAfsの値も 2. 0を超 えると、カバードステント 10の長軸方向の曲げ剛性が高くなり、体内管腔の屈曲に追 従しに《なるため好ましくない。さらに、カバー材 30は、ステント 20の拡径状態で、 ステント 20の円周方向に沿って 1. 2〜3. 0倍に延伸されて用いられる力 1. 2倍未 満で延伸した場合、カバー材 30がステント 20に十分に密着せず、カバー材 30が体 内管腔で剥がれるおそれがある。一方、カバー材 30を 3. 0倍以上に延伸した場合、 カバー材 30はステント 20に十分に密着する力 カバー材 30が規定値以上に引き伸 ばされるため、曲げ剛性は高くなる。それゆえに、本発明の実施形態に係るカバード ステント 10は、上記に規定された剛性を、カバー材 30は、上記に規定された延伸倍 率の範囲内で製造されることが好ま 、。  [0042] If the value of RfcZRfs exceeds 1.5, the rigidity in the radial direction of the covered stent 10 is increased, and stimulation to the body lumen wall is increased, which is not preferable. Also, if the value of AfcZAfs exceeds 2.0, the bending stiffness of the covered stent 10 in the long axis direction becomes high and follows the bending of the body lumen, which is not preferable. Furthermore, when the cover material 30 is stretched by 1.2 to 3.0 times along the circumferential direction of the stent 20 in the expanded state of the stent 20, the cover material 30 is stretched by less than 1.2 times. There is a possibility that the cover material 30 does not sufficiently adhere to the stent 20 and the cover material 30 may be peeled off in the body lumen. On the other hand, when the cover member 30 is stretched by 3.0 times or more, the cover member 30 is sufficiently tightly attached to the stent 20 and the cover member 30 is stretched to a specified value or more, so that the bending rigidity is increased. Therefore, it is preferable that the covered stent 10 according to the embodiment of the present invention is manufactured with the rigidity defined above, and the cover member 30 is manufactured within the range of the stretching ratio defined above.
[0043] この規定された比率により、カバードステントの径ゃカバー材の材質が設計変更さ れても、カバードステントの径方向の剛性および長軸方向の曲げ剛性は常に同じよう に保たれる。したがって本発明のカバードステントは、体内管腔に留置されても体内 管腔の動きや屈曲に柔軟に追従することができる。  [0043] With this specified ratio, even if the diameter of the covered stent and the material of the cover material are changed, the radial stiffness and the bending stiffness in the major axis direction of the covered stent are always kept the same. Therefore, the covered stent of the present invention can flexibly follow the movement and bending of the body lumen even when it is placed in the body lumen.
[0044] (カバードステントの製造方法） 図 2 (a)は、本発明のカバードステント 10の製造方法を示す概略図である。本発明 の実施形態に係るカバードステント 10の製造方法は次の通りである。まず、ステント 2 0を、その外径力 1/3〜2/3の寸法になるまで縮径させるステント縮径工程 (第一 縮径工程) S1を有している。次に、この状態で、縮径された状態の外径一周分の大 きさのカバー材 30を被覆させるカバー材被覆工程 S2を有している。そして、カバー 材 30を巻き付けたカバードステント 10を、上記同様、図 5に示すステントデリバリー力 テーテルの外管（シース） 101などの内側管腔に挿入するために、さらに縮径させる ステント縮径工程 (第二縮径工程) S3を有している。なお、カバー材の材質によって は、カバー材の大きさは、ステントの縮径された状態の外径一周分に限られず、ステ ントの縮径された状態の外径一周分を一周分として複数回巻き付けてもよい。 [0044] (Method for producing covered stent) FIG. 2 (a) is a schematic view showing a method for producing the covered stent 10 of the present invention. The method for manufacturing the covered stent 10 according to the embodiment of the present invention is as follows. First, the stent 20 has a stent diameter-reducing step (first diameter-reducing step) S1 for reducing the diameter of the stent 20 until the outer diameter force becomes 1/3 to 2/3. Next, in this state, there is a cover material coating step S2 for covering the cover material 30 having a size corresponding to one round of the outer diameter in the reduced diameter state. Then, the covered stent 10 wound with the cover material 30 is further reduced in diameter so as to be inserted into an inner lumen such as the outer tube (sheath) 101 of the stent delivery force tater shown in FIG. (Second diameter reduction step) S3 is included. Depending on the material of the cover material, the size of the cover material is not limited to the outer diameter of the stent in a reduced diameter state, and a plurality of outer diameters of the stent in a reduced diameter may be included in one circle. You may wind around.
[0045] 一方、従来のカバードステント 90を製造する場合、図 2 (b)に示すように、ステント 9 9にカバー材 95を巻き付ける。その際、ステント 99を縮径しないで (拡径状態におい て）、その外周に一周分の大きさのカバー材 95を巻き付ける工程 S10を有していた。 そして、カバー材 95を巻き付けた後、これを図 5に示すステントデリバリーカテーテル 100の外管（シース） 101などの内側管腔に挿入するために、縮径する工程 S11を有 していた。 On the other hand, when the conventional covered stent 90 is manufactured, the cover material 95 is wound around the stent 99 as shown in FIG. 2 (b). At this time, the stent 99 had a step S10 in which the diameter of the stent 99 was not reduced (in the diameter-expanded state), and the cover material 95 having a size corresponding to one circumference was wound around the outer periphery. Then, after the cover material 95 is wound, there is a step S11 for reducing the diameter in order to insert the cover material 95 into an inner lumen such as the outer tube (sheath) 101 of the stent delivery catheter 100 shown in FIG.
[0046] このように、本発明のカバードステントは、ー且、ステントの外径が 1Z3〜2Z3の寸 法になるまで縮径してから、縮径された状態の一周分の大きさのカバー材を巻き付け る。これにより、カバードステント 10が、体内管腔に留置されて径を拡張させたときに 、カバー材 30がステント 20によって引き伸ばされ、ステント 20とカバー材 30とが密着 する。この結果、接着剤によらないでもステント 20とカバー材 30とを一体ィ匕させること ができる。したがって体内管腔に留置したときに体内管腔の動きや屈曲によってカバ ー材 30がステント 20に抱き付いて剥がれることがない。また、接着剤を使用しないで すむことで、カバードステントの剛性を低く抑えることができ、カバードステント 10を体 内管腔に留置しても、体内管腔の動きや屈曲によってカバードステント 10が留置位 置力 逸脱することを防止できる。  Thus, the covered stent of the present invention is a cover having a size corresponding to one round after the diameter of the stent is reduced until the outer diameter of the stent becomes 1Z3 to 2Z3. Wrap the material. As a result, when the covered stent 10 is placed in the body lumen to expand its diameter, the cover material 30 is stretched by the stent 20 and the stent 20 and the cover material 30 are brought into close contact with each other. As a result, the stent 20 and the cover material 30 can be integrated together without using an adhesive. Therefore, the cover material 30 does not cling to the stent 20 due to movement or bending of the body lumen when it is placed in the body lumen. In addition, by not using an adhesive, the rigidity of the covered stent can be kept low. Even if the covered stent 10 is placed in the body lumen, the covered stent 10 is placed by the movement or bending of the body lumen. Positional force Deviation can be prevented.
[0047] 従来のカバードステントは、縮径せずにカバー材を被覆して!/ヽたため、製造過程で 縮径した際に余ったカバー材は折りたたまれて ヽた。これによりその折りたたまれる力 バー材の量が多いため、嵩高くなり、ステントの留置に用いられる径の小さなシース（ 図 5参照）に入りにくいという問題があった。また、そのため、折りたたまれたカバー材 が互いにくつついて、カバードステントの拡径阻害が生じやすくなり、デリバリーカテ 一テルなどにより体内管腔にカバードステントを挿入する際に、カバードステントを容 易に留置できな 、と 、う問題もあった。 [0047] The conventional covered stent was covered / covered without being reduced in diameter, so that the remaining cover material was folded when the diameter was reduced in the manufacturing process. This allows the folding force Due to the large amount of the bar material, there is a problem that it becomes bulky and it is difficult to enter a sheath with a small diameter (see FIG. 5) used for stent placement. For this reason, the folded cover materials are sticking to each other, and the diameter of the covered stent tends to be hindered. There was also a problem that could not be done.
しかし、本発明のカバードステントのように、ー且、ステントの外径を縮径してから、 カバー材を巻き付けると、上記シースに挿入するためにさらに縮径したときのカバー 材のだぶつきが減少し、カバードステントを体内管腔へ容易に留置することができる 実施例  However, as in the case of the covered stent of the present invention, when the outer diameter of the stent is reduced and then the cover material is wound, the cover material may be loosened when the diameter is further reduced for insertion into the sheath. And the covered stent can be easily placed in the body lumen.
[0048] 以下、本発明を実施例により具体的に説明する。  Hereinafter, the present invention will be specifically described with reference to examples.
1.試験片の作製  1. Preparation of test piece
(実施例 1)  (Example 1)
ステントには、特許文献 1に記載のステント（以下、「TypeA」という。）を用いた。力 バー材には、国際公開公報 WO2005Z051450号公報に記載の上記ハ-カム膜（ 以下、単に「ノヽ二カム膜」という。）を用いて、カバードステントの試験片を作製した。  The stent described in Patent Document 1 (hereinafter referred to as “Type A”) was used as the stent. A covered stent test piece was prepared using the above-mentioned Hercam film described in International Publication WO2005Z051450 (hereinafter, simply referred to as “No. 2 cam film”) as the force bar material.
[0049] ノヽ-カム膜は、 1, 2—ポリブタジエン（商品名： RB820 JSR製）の 3mg/mLクロ口 ホルム溶液を直径 20cmのガラスシャーレにキャストし、高湿度の空気を当てながらド ラフト中でクロ口ホルムを揮発させて作製した。得られたノヽ-カム膜の初期弾性率は 4 6kPaであった。初期弾性率の測定方法としては、試験片をチャック 150、 150間距 離 10mmとして RHEO METER (NRM - 2002J,不動工業株式会社製）で 20m mZminの引張速度で測定した（図 4参照)。初期弾性率は、伸度 0〜15%までの引 張強度曲線 (横軸:伸度 (mm)、縦軸：引張荷重 (N))の近似曲線の傾きを、引張試 験片の断面積で除した値とした。 [0049] The No-Cam membrane was cast in a glass petri dish with a diameter of 20 cm in diameter using a 3 mg / mL chloroform solution of 1,2-polybutadiene (trade name: manufactured by RB820 JSR). It was prepared by volatilizing the black mouth form. The obtained elastic cam film had an initial elastic modulus of 46 kPa. The initial elastic modulus was measured using a RHEO METER (NRM-2002J, manufactured by Fudo Kogyo Co., Ltd.) at a tensile speed of 20 mmZmin with a test piece having a distance of 10 mm between the chuck 150 and 150 (see FIG. 4). The initial elastic modulus is the slope of the approximate curve of the tensile strength curve (horizontal axis: elongation (mm), vertical axis: tensile load (N)) from 0 to 15% elongation, and the cross-sectional area of the tensile specimen. The value divided by.
この試験片の製造方法において、ステントにカバー材を巻き付ける前に、まず、ステ ントの外径を 5mmの寸法になるまで縮径した。そして、この状態で、カバー材を、縮 径された状態でのステント一周分の大きさを 1回分として 8回巻き付けて、さらに縮径 することによりカノ一ドステントを作製した。 [0050] このカバードステントについて、拡径状態での円周方向の寸法を測定した。また、力 バードステントにおいて、その長軸方向に沿ってカバー材を切断し、切断して応力を 取り除いた未延伸状態のカバー材の円周方向の長さを測定した。カバードステントに おいて、拡径状態での円周方向の寸法は 28mmであり、切断した後の未延伸状態 のカバー材の円周方向の長さは 22mmであった。よって、延伸倍率は 1. 3であった 。また、カバードステントの拡径率は 99%であった。 In this test piece manufacturing method, before the cover material was wound around the stent, the outer diameter of the stent was first reduced to a size of 5 mm. In this state, the cover material was wound eight times with the size of one round of the stent in the reduced state as a single stroke, and further reduced in diameter to produce a cannulated stent. [0050] With respect to this covered stent, the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 28 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 22 mm. Therefore, the draw ratio was 1.3. The diameter expansion rate of the covered stent was 99%.
[0051] (実施例 2)  [0051] (Example 2)
カバー材に、編物、ここではストッキング（ダンゼ株式会社製、 rsoft fit No. SM -93SJ (材質:ナイロン、ポリウレタン）、約 200 /z m厚）を用いた。カバー材巻き付け 回数を 1回とすること以外は、実施例 1と同様の方法でカバードステントを作製した。 このカバードステントを構成する編物の初期弾性率は 1. 2kPaであった。  A knitted fabric, here stockings (manufactured by Danze Co., Ltd., rsoft fit No. SM-93SJ (material: nylon, polyurethane), approximately 200 / z m thickness) was used as the cover material. A covered stent was produced in the same manner as in Example 1 except that the number of times of covering of the cover material was one. The initial elastic modulus of the knitted fabric constituting the covered stent was 1.2 kPa.
[0052] このカバードステントについて、拡径状態での円周方向の寸法を測定した。また、力 バードステントにおいて、その長軸方向に沿ってカバー材を切断し、切断して応力を 取り除いた未延伸状態のカバー材の円周方向の長さを測定した。カバードステントに おいて、拡径状態での円周方向の寸法は 27mmであり、切断した後の未延伸状態 のカバー材の円周方向の長さは 16mmであった。よって、延伸倍率は 1. 7であった 。また、カバードステントの拡径率は 96%であった。  [0052] For this covered stent, the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 27 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 16 mm. Therefore, the draw ratio was 1.7. The diameter expansion rate of the covered stent was 96%.
[0053] (実施例 3)  [0053] (Example 3)
ステントに、特許文献 2に記載のステント（以下、「TypeB^いう。）を用いること以外 は、実施例 1と同様の方法でカバードステントを作製した。  A covered stent was produced in the same manner as in Example 1 except that the stent described in Patent Document 2 (hereinafter referred to as “TypeB ^”) was used as the stent.
[0054] このカバードステントについて、拡径状態での円周方向の寸法を測定した。また、力 バードステントにおいて、その長軸方向に沿ってカバー材を切断し、切断して応力を 取り除いた未延伸状態のカバー材の円周方向の長さを測定した。カバードステントに おいて、拡径状態での円周方向の寸法は 27mmであり、切断した後の未延伸状態 のカバー材の円周方向の長さは 20mmであった。よって、延伸倍率は 1. 4であった 。また、カバードステントの拡径率は 96%であった。  [0054] With respect to this covered stent, the dimension in the circumferential direction in the expanded diameter state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 27 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 20 mm. Therefore, the draw ratio was 1.4. The diameter expansion rate of the covered stent was 96%.
[0055] (実施例 4)  [Example 4]
カバー材に、編物、ここではストッキング（ダンゼ株式会社製、 rsoft fit No. SM -93SJ (材質:ナイロン、ポリウレタン）、約 200 /z m厚）を用いた。カバー材巻き付け 回数を 1回とすること以外は、実施例 3と同様の方法でカバードステントを作製した。 Cover material, knitted fabric, stockings (manufactured by Danze Co., Ltd., rsoft fit No. SM -93SJ (material: nylon, polyurethane), about 200 / zm thick) was used. A covered stent was produced in the same manner as in Example 3 except that the number of times of covering of the cover material was one.
[0056] このカバードステントについて、拡径状態での円周方向の寸法を測定した。また、力 バードステントにおいて、その長軸方向に沿ってカバー材を切断し、切断して応力を 取り除いた未延伸状態のカバー材の円周方向の長さを測定した。カバードステントに おいて、拡径状態での円周方向の寸法は 28mmであり、切断した後の未延伸状態 のカバー材の円周方向の長さは 16mmであった。よって、延伸倍率は 1. 8倍であつ た。また、カバードステントの拡径率は 99%であった。  [0056] For this covered stent, the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 28 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 16 mm. Therefore, the draw ratio was 1.8 times. The diameter expansion rate of the covered stent was 99%.
[0057] (実施例 5)  [0057] (Example 5)
ステントの外径を 3mmの寸法になるまで縮径したこと以外は、実施例 1と同様の方 法でカバードステントを作製した。  A covered stent was produced in the same manner as in Example 1 except that the outer diameter of the stent was reduced to 3 mm.
[0058] このカバードステントについて、拡径状態での円周方向の寸法を測定した。また、力 バードステントにおいて、その長軸方向に沿ってカバー材を切断し、切断して応力を 取り除いた未延伸状態のカバー材の円周方向の長さを測定した。カバードステントに おいて、拡径状態での円周方向の寸法は 22mmであり、切断した後の未延伸状態 のカバー材の円周方向の長さは 13mmであった。よって、延伸倍率は 1. 7倍であつ た。また、カバードステントの拡径率は 70%であった。  [0058] With respect to this covered stent, the dimension in the circumferential direction in the expanded diameter state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 22 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 13 mm. Therefore, the draw ratio was 1.7 times. The diameter expansion rate of the covered stent was 70%.
[0059] (実施例 6)  [Example 6]
ステントの外径を 3mmの寸法になるまで縮径したこと以外は、実施例 4と同様の方 法でカバードステントを作製した。  A covered stent was produced in the same manner as in Example 4 except that the outer diameter of the stent was reduced to 3 mm.
[0060] このカバードステントについて、拡径状態での円周方向の寸法を測定した。また、力 バードステントにおいて、その長軸方向に沿ってカバー材を切断し、切断して応力を 取り除いた未延伸状態のカバー材の円周方向の長さを測定した。カバードステントに おいて、拡径状態での円周方向の寸法は 27mmであり、切断した後の未延伸状態 のカバー材の円周方向の長さは 14mmであった。よって、延伸倍率は 1. 9倍であつ た。また、カバードステントの拡径率は 93%であった。  [0060] With respect to this covered stent, the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the circumferential dimension in the expanded state was 27 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 14 mm. Therefore, the draw ratio was 1.9 times. The diameter expansion rate of the covered stent was 93%.
[0061] (比較例 1)  [0061] (Comparative Example 1)
カバー材に、初期弾性率が高い平膜 (初期弾性率 160kPa)を用いること以外は、 実施例 1と同様の方法でカバードステントを作製した。このカバードステントを構成す る平膜は、直径 15cmのガラスシャーレに、 1, 2—ポリブタジエン（商品名： RB820 J SR製）の 7. 8mgZmLクロ口ホルム溶液をキャストした。これは、ドラフト中でクロロホ ノレムを揮発させること〖こより得ることができる。 Except for using a flat membrane with a high initial elastic modulus (initial elastic modulus 160 kPa) as the cover material, A covered stent was produced in the same manner as in Example 1. The flat membrane constituting this covered stent was cast in a glass petri dish having a diameter of 15 cm with a 7.8 mg ZmL chloroform solution of 1,2-polybutadiene (trade name: manufactured by RB820 JSR). This can be obtained by volatilizing chlorophenol in a draft.
[0062] このカバードステントについて、拡径状態での円周方向の寸法を測定した。また、力 バードステントにおいて、その長軸方向に沿ってカバー材を切断し、切断して応力を 取り除いた未延伸状態のカバー材の円周方向の長さを測定した。カバードステントに おいて、拡径状態での円周方向の寸法は 24mmであり、切断した後の未延伸状態 のカバー材の円周方向の長さは 20mmであった。よって、延伸倍率は 1. 2倍であつ た。また、カバードステントの拡径率は 83%であった。  [0062] For this covered stent, the circumferential dimension in the expanded state was measured. Moreover, in the force bird stent, the cover material was cut along the long axis direction, and the length of the cover material in an unstretched state after cutting to remove the stress was measured. In the covered stent, the dimension in the circumferential direction in the expanded state was 24 mm, and the length in the circumferential direction of the unstretched cover material after cutting was 20 mm. Therefore, the draw ratio was 1.2 times. The diameter expansion rate of the covered stent was 83%.
[0063] 上記の実施例 1〜6および比較例 1における測定結果を表 1に示した。  [0063] Table 1 shows the measurement results in Examples 1 to 6 and Comparative Example 1 described above.
[0064] [表 1] [0064] [Table 1]
Figure imgf000017_0001
Figure imgf000017_0001
[0065] 2.評価結果 [0065] 2. Evaluation results
(実施例 1〜6について）  (Examples 1 to 6)
表 1において、実施例 1〜6は、カバードステントのステントに対する径方向の剛性 の比率である Rfc/Rfsについて、いずれも 1. 5以下で、本発明の規定値を満たした 。また、カバードステントのステントに対する長軸方向の剛性の比率である AfcZAfs は、いずれも 2. 0以下で、これも本発明の規定値を満たした。  In Table 1, in Examples 1 to 6, Rfc / Rfs, which is the ratio of the radial stiffness of the covered stent to the stent, was 1.5 or less and satisfied the specified value of the present invention. In addition, AfcZAfs, which is the ratio of the rigidity of the covered stent to the stent in the long axis direction, was 2.0 or less, which also satisfied the specified value of the present invention.
さらに、実施例 1〜5は、カバードステントの径方向の剛性の比率である Rfc力 い ずれも 15N以下であり、また、カバードステントの長軸方向の剛性の比率である Afc 力 いずれも 0. 3N以下であった。  Further, in Examples 1 to 5, the Rfc force, which is the ratio of the radial stiffness of the covered stent, is 15 N or less, and the Afc force, which is the ratio of the rigidity in the long axis direction of the covered stent, is 0. 3N or less.
[0066] 一方、実施例 1〜4では、ステントの巻き付け径の大きさを 5mmとし、この際カバー 材の延伸倍率が 1. 3〜1. 8倍であった。また、実施例 5〜6は、ステントの巻き付け 径の大きさを 3mmとし、この際カバー材の延伸倍率が 1. 7〜1. 9倍であった。いず れの実施例においても本発明のカバー材の延伸倍率の範囲を満たしており、このた め、体内管腔に留置しても体内を刺激することなぐ所定の位置で安定的に機能を 発揮できることが分力つた。 [0066] On the other hand, in Examples 1 to 4, the wound diameter of the stent was 5 mm, and the draw ratio of the cover material was 1.3 to 1.8 times. In Examples 5 to 6, the wound diameter of the stent was 3 mm, and the draw ratio of the cover material was 1.7 to 1.9 times. In any of the examples, the range of the stretch ratio of the cover material of the present invention is satisfied, so that even if it is placed in the body lumen, it functions stably at a predetermined position without stimulating the body. I was able to demonstrate what I could do.
[0067] (比較例 1について） [0067] (Comparative Example 1)
表 1において、比較例 1は、カバードステントのステントに対する径方向の剛性の比 率である RfcZRfsは 1. 5よりも大きぐ本発明の規定値を満たさな力つた。  In Table 1, in Comparative Example 1, RfcZRfs, which is the ratio of the radial stiffness to the stent of the covered stent, did not satisfy the specified value of the present invention greater than 1.5.
さらに、比較例 1は、カバードステントの径方向の剛性である Rfcが 15Nよりも大きく 、本発明の規定値を満たさな力 たため、本発明のカバードステントとしては適当で はない。  Furthermore, Comparative Example 1 is not suitable as the covered stent of the present invention because Rfc, which is the rigidity in the radial direction of the covered stent, is larger than 15N and does not satisfy the specified value of the present invention.
[0068] 比較例 1は初期弾性率が高い RB平膜を用いたため、カバードステントの拡径状態 でのカバー材の延伸応力が大きくなり、長軸方向の曲げ剛性 Afcが 0. 3Nよりも大き ぐ本発明の規定値以内に納まらな力つた。結果としてこのカバードステントは長軸方 向の曲げ剛性の高 、ものとなることが分力つた。  [0068] Since RB flat membrane with a high initial elastic modulus was used in Comparative Example 1, the stretching stress of the cover material in the expanded state of the covered stent increased, and the flexural rigidity Afc in the major axis direction was greater than 0.3N. The power was not within the specified value of the present invention. As a result, it was found that this covered stent had high bending rigidity in the long axis direction.
[0069] 以上、現時点において、もっとも実践的であり、かつ好ましいと思われる実施形態に 関連して本発明を説明したが、本発明は、本願明細書中に開示された実施形態に 限定されるものではなぐ請求の範囲および明細書全体力 読み取れる発明の要旨 或いは思想に反しな!/、範囲で適宜変更可能であり、そのような変更を伴うカバードス テントおよびカバードステントの製造方法もまた本発明の技術的範囲に包含されるも のとして理解されなければならな!/、。 [0069] While the present invention has been described with reference to the most practical and preferred embodiments at the present time, the invention is limited to the embodiments disclosed herein. Claims that are not things and overall strength of the specification Or, it is contrary to the idea! / Can be appropriately changed within the scope, and the manufacturing method of the covered stent and the covered stent accompanying such a change must also be understood as being included in the technical scope of the present invention. What! /

Claims

請求の範囲 The scope of the claims
[1] 筒状のステントと、このステントの外周部分に設けられているカバー材とを備え、体 内管腔に留置して用いられるカバードステントであって、  [1] A covered stent comprising a cylindrical stent and a cover material provided on an outer peripheral portion of the stent, and being used in an indwelling body lumen,
前記ステントの径方向の剛性を Rfs、前記ステントの長軸方向の曲げ剛性を Afs、 前記カバードステントの径方向の剛性を Rfc、前記カバードステントの長軸方向の曲 げ剛性を Afcとしたとき、 RfcZRfs≤l. 5で、かつ AfcZAfs≤2. 0の関係を満たし 前記カバー材は、前記ステントの拡径状態で、前記ステントの円周方向に沿って 1 . 2〜3. 0倍に延伸されるカバードステント。  When the radial stiffness of the stent is Rfs, the bending stiffness of the stent in the long axis direction is Afs, the radial stiffness of the covered stent is Rfc, and the bending stiffness of the covered stent in the long axis direction is Afc, RfcZRfs≤l.5 and AfcZAfs≤2.0 is satisfied. The cover material is stretched 1.2 to 3.0 times along the circumferential direction of the stent in the expanded diameter state of the stent. Covered stent.
[2] 前記カバー材は、その初期弾性率が 50kPa以下である、請求の範囲第 1項に記載 のカバードステント。 [2] The covered stent according to claim 1, wherein the cover material has an initial elastic modulus of 50 kPa or less.
[3] 前記カバードステントの径方向の剛性 Rfcと、前記カバードステントの長軸方向の曲 げ剛性 Afcとの関係力 30≤RfcZAfc≤100となる、請求の範囲第 1項に記載の力 バードステント。  [3] The force bird stent according to claim 1, wherein the relational force between the radial rigidity Rfc of the covered stent and the bending rigidity Afc of the long axis direction of the covered stent is 30≤RfcZAfc≤100. .
[4] 前記カバー材は、ハ-カム膜からなることを特徴とする、請求の範囲第 1項に記載 のカバードステント。  [4] The covered stent according to claim 1, wherein the cover material is made of a Hercam film.
[5] 前記カバー材は、編物であることを特徴とする、請求の範囲第 1項に記載のカバー ドステント。  [5] The covered stent according to claim 1, wherein the cover material is a knitted fabric.
[6] 前記カバードステントの径方向の剛性 Rfcが 15N以下で、かつ前記カバードステン トの長軸方向の曲げ剛性 Afcが 0. 3N以下であることを特徴とする、請求の範囲第 1 項に記載のカバードステント。  [6] The radial stiffness Rfc of the covered stent is 15N or less, and the bending stiffness Afc in the major axis direction of the covered stent is 0.3N or less. The covered stent as described.
[7] 筒状のステントと、このステントの外周部分に設けられるカバー材とを備え、体内管 腔に留置して用いられる請求の範囲第 1項に記載の力バーステントの製造方法であ つて、 [7] The method for producing a force bar stent according to claim 1, comprising a cylindrical stent and a cover material provided on an outer peripheral portion of the stent, and used by being placed in a body lumen. ,
前記ステントを、その外径が 1Z3〜2Z3の寸法になるまで縮径させるステント縮径 工程と、前記縮径したステントの外周部分に前記カバー材を被覆させるカバー材被 覆工程と、  A stent diameter-reducing step of reducing the diameter of the stent until the outer diameter thereof becomes a dimension of 1Z3 to 2Z3; and a cover material covering step of covering the outer peripheral portion of the diameter-reduced stent with the cover material;
を備えることを特徴とする、カバードステントの製造方法。  A method for producing a covered stent, comprising:
PCT/JP2007/063034 2006-06-30 2007-06-28 Covered stent and method of producing covered stent WO2008001865A1 (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5575327B2 (en) * 2011-03-08 2014-08-20 株式会社パイオラックスメディカルデバイス Stent
WO2014171448A1 (en) 2013-04-18 2014-10-23 国立大学法人 山形大学 Stent to be placed in bile duct and process for producing same
JP2015161576A (en) * 2014-02-27 2015-09-07 日本ゼオン株式会社 Measuring method and measuring apparatus for measuring deformability of stent in bending direction
US9637722B2 (en) 2013-07-09 2017-05-02 Toyoda Gosei Co., Ltd. Production method of polyurethane porous membrane to be used for at least one of applications of cell culture and cancer cell growth inhibition
JP2018161163A (en) * 2017-03-24 2018-10-18 ニプロ株式会社 Stent
CN111419470A (en) * 2020-03-17 2020-07-17 首都医科大学附属北京安贞医院 Support laminating machine
CN113367834A (en) * 2020-03-10 2021-09-10 上海微创医疗器械（集团）有限公司 Covered stent and preparation method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1099448A (en) * 1996-05-21 1998-04-21 Cordis Europ Nv Tube-like artificial organ
JPH10510445A (en) * 1994-12-16 1998-10-13 フーエール，アラン Surgical expandable body tube for expanding a body conduit
JP2005152004A (en) * 2003-11-20 2005-06-16 Terumo Corp Covered stent
JP2005152527A (en) * 2003-11-28 2005-06-16 Zeon Medical Inc Stent for digestive system
JP2006130064A (en) * 2004-11-05 2006-05-25 National Cardiovascular Center Stent delivery system

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2247891C (en) * 1996-03-07 2007-07-31 Med Institute, Inc. An expandable stent
US7147659B2 (en) * 2004-10-28 2006-12-12 Cordis Neurovascular, Inc. Expandable stent having a dissolvable portion

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10510445A (en) * 1994-12-16 1998-10-13 フーエール，アラン Surgical expandable body tube for expanding a body conduit
JPH1099448A (en) * 1996-05-21 1998-04-21 Cordis Europ Nv Tube-like artificial organ
JP2005152004A (en) * 2003-11-20 2005-06-16 Terumo Corp Covered stent
JP2005152527A (en) * 2003-11-28 2005-06-16 Zeon Medical Inc Stent for digestive system
JP2006130064A (en) * 2004-11-05 2006-05-25 National Cardiovascular Center Stent delivery system

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5575327B2 (en) * 2011-03-08 2014-08-20 株式会社パイオラックスメディカルデバイス Stent
WO2014171448A1 (en) 2013-04-18 2014-10-23 国立大学法人 山形大学 Stent to be placed in bile duct and process for producing same
US10080640B2 (en) 2013-04-18 2018-09-25 National University Corporation Yamagata University Stent to be placed in bile duct
US9637722B2 (en) 2013-07-09 2017-05-02 Toyoda Gosei Co., Ltd. Production method of polyurethane porous membrane to be used for at least one of applications of cell culture and cancer cell growth inhibition
JP2015161576A (en) * 2014-02-27 2015-09-07 日本ゼオン株式会社 Measuring method and measuring apparatus for measuring deformability of stent in bending direction
JP2018161163A (en) * 2017-03-24 2018-10-18 ニプロ株式会社 Stent
CN113367834A (en) * 2020-03-10 2021-09-10 上海微创医疗器械（集团）有限公司 Covered stent and preparation method thereof
CN113367834B (en) * 2020-03-10 2024-02-27 上海微创医疗器械（集团）有限公司 Tectorial membrane bracket and preparation method thereof
CN111419470A (en) * 2020-03-17 2020-07-17 首都医科大学附属北京安贞医院 Support laminating machine
CN111419470B (en) * 2020-03-17 2022-08-30 首都医科大学附属北京安贞医院 Support laminating machine

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