Classifications

• • 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
  • A61F2/88—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 formed as helical or spiral coils
• • 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
  • A61F2/01—Filters implantable into blood vessels
• • 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
  • A61F2210/00—Particular material properties of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
  • A61F2210/0014—Particular material properties of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof using shape memory or superelastic materials, e.g. nitinol
  • A61F2210/0019—Particular material properties of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof using shape memory or superelastic materials, e.g. nitinol operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• • 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
  • A61F2250/00—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
  • A61F2250/0003—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof having an inflatable pocket filled with fluid, e.g. liquid or gas
• • 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
  • A61F2250/00—Special features of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
  • A61F2250/0058—Additional features; Implant or prostheses properties not otherwise provided for
  • A61F2250/0067—Means for introducing or releasing pharmaceutical products into the body

Definitions

• This invention is directed to a novel stent. More particularly, this invention is directed to a spiral, wound stent wherein the stent is comprised of a tubular material.
• implantable medical devices such as stents, grafts, or filters
• shape or configuration of such devices may vary, they are typically comprised of solid wire.
• the elastic property of the wire was used, by creating stress in the wire.
• the purpose for creating the stress was to reduce the stent's diameter and restrain the stent, before insertion of the device into a patient's body, whereupon, after the stent was inserted and the restraining means was removed, the stent expands and the stress releases.
• FIG. 1 is a partial, longitudinal cross-sectional view of an embodiment of the invention in unstressed condition
• Fig. 2 is a cross-section of the segment in Fig. 1;
• Fig. 3 is a partial, longitudinal cross-sectional view of an embodiment of the invention under stress to reduce the diameter
• Fig. 4 is a cross-section of the segment in Fig. 3;
• Fig. 5 is a perspective view, with partial sectional areas, of an embodiment of the invention.
• Fig. 6 is a partial cross-sectional view of an embodiment of the invention loaded on a delivery catheter.
• implantable medical devices such as stents, grafts, or filters
• the wire from which such devices are made is hollow, i.e., tubular, rather than solid.
• tubular wires with relatively thin walls are bent, they prove to be much more flexible during bending than would be expected based upon the behavior of solid wire.
• solid wire is bent, the shape of the cross-section remains substantially unchanged, which means that fibers or elements of the wire are unevenly stressed. For example, elements of the wire opposite to the curvature would be strained, whereas elements on the radius of the curvature would be compressed.
• U.S. Pat. No. 4,813,925 describes a spiral ureteral stent with a lumen extending along the entire length of the stent.
• the stent may be straightened by means of a wire stylet inserted into the lumen, to facilitate placement of the stent in the ureter. This means that to insert the device into the body, the radius of curvature of segments of the device is increased. In contrast, in the present invention, to insert the device into the body the radius of curvature is decreased without inserting any device into the inner lumen.
• U.S. Pat. No. 5,234,456 describes a hydrophilic stent having a permeable or semi-permeable hollow wall with hydrophilic material disposed therein.
• the hydrophilic material swells upon introduction of a liquid into the hollow wall, to thereby achieve inflation of the stent.
• This use of a hollow wall is totally different from the present invention, as there is no stress in the stent wall due to being constrained and there is no reduction of stress in the stent wall during opening of the stent.
• a segment 1 of a tubular wire useful according to the invention is shown in Figs. 1 and 2.
• the segment has concave 3 and convex 4 surfaces that are unstressed.
• the radius of curvature 5 extends to the middle 7 of lumen 8.
• Segment 1 has a circular cross- section, as shown in Fig. 2.
• Figs. 3 and 4 represent segment 1 under stress. Tensile forces at the convex surface 4 and compression forces at the concave surface 3, act upon the cross- sectional shape of segment 1. The result is that the radius of curvature 9 is smaller than radius of curvature 5, and the previously circular cross-section becomes elliptical, as shown in Fig. 4. This flattening of the cross-section affects the strain of the longitudinal elements of the tubular wire.
• Fig. 5 is a perspective view of an embodiment of the invention in unstressed condition.
• the stent 12 comprises a spiral coil 14 of hollow, tubular material.
• the inner lumen 16 and coil 14 can be seen in partial cross-sectional areas 18 and 19.
• stent 12 When stent 12 is stressed to reduce its diameter, it can be positioned in stressed form on a catheter 20.
• the tubular material will assume an elliptical cross-section 22, as shown in Fig. 6.
• the balls 24 of stent 12 are restrained, for example, on the outer surface of catheter 20 (not shown) .
• Particulars regarding such restraining systems and the delivery of stents can be seen, for example, in U.S. Patents Nos. 5,246,445 and 5,372,600, both of which are incorporated herein by reference.
• the tubular material useful according to the invention can comprise any suitable physiologically acceptable metallic material, such as stainless steel or an alloy. Especially useful are shape memory alloys, particularly nickel-titanium alloys known as nitinol. Also, the lumen of the tubular material may contain radiopaque material or pharmacological substances. The wall of the tubing may have one or more small or miniature openings so that such pharmacological substances can be dispensed. Each such opening could be from about 0.1 to 1 mm in actual or effective diameter.
• the stents useful according to the invention can have shapes and sizes that will vary according to application.
• the tubular wire could have an o.d. of from about 0.3 to 1 mm, preferably about 0.4 to 0.6 mm, and an i.d. of from about 0.2 to 0.8 mm, preferably from about 0.4 to 0.5 mm.
• the outside diameter of the coiled stents could be from about 0.25 to 2.5 cm, with a coiled length of from about 10 to
• Stent preparation procedures are well known and are, for example, described in one or more of the above patents incorporated herein by reference.

Landscapes

• Health & Medical Sciences (AREA)
• Engineering & Computer Science (AREA)
• Biomedical Technology (AREA)
• Heart & Thoracic Surgery (AREA)
• Transplantation (AREA)
• Oral & Maxillofacial Surgery (AREA)
• Cardiology (AREA)
• Vascular Medicine (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Prostheses (AREA)
• Media Introduction/Drainage Providing Device (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=23560467

Family Applications (1)

Country Status (3)

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Citations (5)

Family Cites Families (12)

• 1996
  • 1996-02-27 WO PCT/US1996/002262 patent/WO1996026682A1/en not_active Application Discontinuation
  • 1996-02-27 AU AU50250/96A patent/AU5025096A/en not_active Abandoned
  • 1996-02-27 EP EP96907075A patent/EP0812165A4/de not_active Withdrawn

Patent Citations (5)

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