WO1995026762A1 - Intravascular polymeric stent - Google Patents
Intravascular polymeric stent Download PDFInfo
- Publication number
- WO1995026762A1 WO1995026762A1 PCT/NL1995/000122 NL9500122W WO9526762A1 WO 1995026762 A1 WO1995026762 A1 WO 1995026762A1 NL 9500122 W NL9500122 W NL 9500122W WO 9526762 A1 WO9526762 A1 WO 9526762A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- manufactured
- stent
- polymer
- cross
- linked
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/30—Low-molecular-weight compounds
- C08G18/32—Polyhydroxy compounds; Polyamines; Hydroxyamines
- C08G18/3271—Hydroxyamines
- C08G18/3278—Hydroxyamines containing at least three hydroxy groups
-
- 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
- A61L31/04—Macromolecular materials
- A61L31/06—Macromolecular materials obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
-
- 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
Definitions
- the invention relates to an intravascular polymeric stent, more particularly to a stent which is manufactured from a biocompatible, non-thrombogenic material.
- Stents are (spiral) bodies suitable for maintaining the patency of veins in the human body, more particularly veins which have undergone a so-called Dotter treatment.
- an intravascular stent can be plac in the treated segment of the vessels in order to maintain patency.
- the first stents were described in 1969 and consisted of a tubular stainless steel coil spring. Thereafter a large number of other designs, substantially consisting of metal, were developed.
- the metal stents currently in use can be divided into two types, based on the manner of placement, viz. self- expanding or balloon-expanding.
- metal stents have been particularly successful in preventing restenosis, but it is to be expected that complications can occur in the long term.
- Metal stents are far from ideal, since metals are relatively thrombogenic and non- degradable. Moreover, metal stents may perforate the walls of the blood vessel.
- An ideal stent would be compatible in the biological system, i.e. compatible with blood, non- thrombogenic, not inducing any rejection reactions, and biodegradable, while any decomposition products would not be toxic.
- the literature describes degradable intravascular stents which are manufactured from poly(L-lactide) .
- Poly(L- lactide) is a hydrolytically labile semi-crystalline aliphatic polyester which is used in a large number of biomedical applications since the degradation product thereof, L-lactic acid, possesses a very minor toxicity.
- Recent developments, however, have shown that implantation of semi-crystalline poly(L-lactide) may eventually lead to a late tissue reaction because of the presence of small highly crystalline low- molecular poly(L-lactide) particles which are hydrolytically rather stable. These particles can be found at the site of implantation up to 5 years after implantation.
- the object of the invention is to provide an intravascular stent suitable for use in blood vessels after a Dotter therapy, which does not have the disadvantages of the above-described materials.
- such an intravascular stent is manufactured from an amorphous, biocompatible polymer.
- amorphous biocompatible polymers are highly suitable for the manufacture of stents, without possessing the disadvantages of, for instance, the semi-crystalline pol (L-lactide) .
- a next advantage of such a polymeric stent resides in the fact that the material, after the cure of the blood vessel, which takes about three weeks, is absorbed by the body, since the material has no further function anymore.
- the stent can be implanted in the blood vessel by a catheter as an elongated spiral of slight diameter.
- the stent is then thermally expanded to its original spiral shape.
- the polymeric material should have a glass transition temperature just below the body temperature.
- the material of the stents should therefore have a so-called thermal shape memory.
- a suitable stent can be manufactured by the in situ polymerization of suitable starting materials in a spiral-shaped matrix, for instance manufactured from PTFE. After polymerization, the spiral obtained can be stretched to any desired shape above the glass transition temperature of the material. This shape can be frozen after cooling to a temperature below the glass transition temperature. This makes it possible to introduce the stent into the blood vessel via a catheter.
- the stent After the stent has been introduced into the blood vessel, it can expand freely to the original spiral shape at body temperature. The closer to the body temperature the T g of the polymeric material is, the faster the material wil l resume its original shape again. The expanding spiral then anchors itself in the blood vessel by exerting pressure on the wall of the blood vessel. It is therefore preferred to use a material which has a T g between 0°C and 37°C.
- creep resistance is a particularly important property because it should be possible for the elongated spiral to expand completely to its original dimensions upon heating. A permanent deformation as a result of the elongation of the coil spring is undesirable. It has been found, however, that the use of polymeric (amorphous) networks as stent material gives an article of sufficient creep resistance. In practice this means that the creep of the material at body temperature is nil.
- plastics are suitable for th> manufacture of the polymeric stent.
- the common feature of these polymers is that they are amorphous, cross-linked biologically active polymers, which are preferably also biodegradable.
- suitable groups of polymers are the amorphous non-crystallizable polylactic acid networks, the highly cross-linked polyurethane networks, which also includes the conversion products of star prepolyesters, for instance based on lactic acid copolymers, with diisocyanate.
- the extent of cross-linking should be such that the maximum gel content is obtained. Preferably, no unreacted low-molecular components are present.
- the first group of polymers, amorphous non- crystallizable polylactic acid networks comprises inter alia the amorphous copolymers of lactides and glycolides, which have been converted to a network with suitable cross-linking agents.
- cross-linking for the purpose of forming a network is preferably effected with a tetra- or higher functional cyclic ester, preferably with a tetrafunctional cyclic cross-linking agent such as biscaprolactone.
- This group of polymers consists of cross-linked polyurethane networks obtainable by reacting one or more low- molecular polyols with a functionality of three or more and one or more polyisocyanates with a functionality of two or more in the absence of a solvent.
- the polyols are low-molecular.
- the equivalent weight of the polyol is preferably 125 at a maximum.
- 'Equivalent weight' in this case is understood to mean the molecular weight per hydroxyl group.
- the starting material is 3 or 4 functional polyols, although higher functionalities can be used as well. Practically, an upper limit lies at a functionality of 8. It is also possible, however, to include a minor amount of diols in the mixture.
- diols do not give rise to cross-linking, either the amount thereof should be kept low or one should work with substantially 3 or higher functional isocyanates .
- the number of hydroxyl groups coming from a diol will be less than about 10% of the total number of hydroxyl groups.
- Preferred polyols are selected from the group consisting of triethanolamine (TEA), tri-isopropanolamine, 1,1,1, -trimethylol-propane (TMP) , N,N,N' ,N' -tetrakis (2- hydroxypropy1) -ethylenediamine (Quadrol) , octakis(2- hydroxypropyl) penta-erytrytyltetra-amine, tetrakis ⁇ - hydroxyethyl ⁇ methane, 1,1,1 trihydroxyethylpropane, 1,1,1 trihydroxyethylethane and other polyols. It is also possible to use modified or unmodified pentaerytritol or inositol.
- the polyisocyanates which can be used according to this embodiment of the invention are the conventional diisocyanates and higher isocyanates, for instance selected from the group consisting of butanediisocyanate, hexamethylene diisocyanate, dodecane diisocyanate, trans 1,4-cyclohexane diisocyanate, methylene dicyclohexane diisocyanate, lysine di- or triisocyanate, isophorone diisocyanate, p-phenylene diisocyanate, methylene diphenyl diisocyanate, triphenyl- methanetriisocyanate, thiophosphoric acid tris(4-isocyanati- phenyl ester), polymeric methylene diphenyl diisocyanate as well as trimerization products and adducts of these isocyanates, for instance based on polyols. Examples of suitable polyols have been given hereinabove.
- the third product group comprises the conversion products of star prepolyesters and a di-isocyanate, preferably a di-isocyanate based on an L-lysine derivative or on 1,4-diisocyanatobutane.
- a di-isocyanate preferably a di-isocyanate based on an L-lysine derivative or on 1,4-diisocyanatobutane.
- diisocyanate preferably a lysine derivative is used having one of the formulae 1-3 of the sheet of formulae, or 1,4-diisocyanatobutane.
- suitable polyols such as polyester polyols based on lactide, glycolide, and/or lactones such as ⁇ -caprolactone or ⁇ -valerolactone.
- a polyester can be initiated with a suitable low-molecular polyol, such as glycol, pentaerytritol, myo-inositol and the like.
- the material of the polymeric stent is broker down in the body, it is preferred to manufacture the polymer from polymers whose decomposition products are not toxic.
- the three groups of polymers described hereinabove are highly suitable as such, it may be desirable, in order to obtain the desirable strength properties, that a second phase be incorporated into the material, for instance by the introduction of one or more fillers, fibers and/or a second polymeric phase.
- a second polymeric phase in the form of a separate rubber phase, materials are obtained which possess a particularly good combination of mechanical properties.
- Cross-linked poly(lactide- ⁇ -caprolactone;80/20 mole ratio) was manufactured by in situ polymerization in a spiral- shaped PTFE mold.
- a stent was manufactured from a highly cross-linked polyurethane network, using a PTFE mold.
- the starting materials triethanolamine, tetrakis(2-hydroxypropyl) - ethylenediamine and hexamethylenediisocyanate, were purified by distillation at reduced pressure. The components were then mixed and degassed a number of times. With a syringe the mixture was introduced into the mold and gelled at room temperature. Then curing was allowed to take place for 24 hours at about 100°C, whereafter the stent was removed from the mold. Re s ults
Abstract
The invention relates to an intravascular polymeric stent manufactured from an amorphous, biocompatible polymer.
Description
Title: Intravascular polymeric stent
The invention relates to an intravascular polymeric stent, more particularly to a stent which is manufactured from a biocompatible, non-thrombogenic material. Stents are (spiral) bodies suitable for maintaining the patency of veins in the human body, more particularly veins which have undergone a so-called Dotter treatment.
In the 1960s Charles Dotter introduced a technique for treating obstruction of coronary arteries (stenosis), which is generally the result of atherosclerosis. This treatment is presently known as the so-called Dotter therapy, a promising and widely accepted alternative to bypass surgery. Important disadvantages of this technique are acute collapse, chronic complete occlusion and restenosis of the affected vessels.
In order to obviate these problems, an intravascular stent can be plac in the treated segment of the vessels in order to maintain patency. The first stents were described in 1969 and consisted of a tubular stainless steel coil spring. Thereafter a large number of other designs, substantially consisting of metal, were developed. The metal stents currently in use can be divided into two types, based on the manner of placement, viz. self- expanding or balloon-expanding.
These metal stents have been particularly successful in preventing restenosis, but it is to be expected that complications can occur in the long term. Metal stents are far from ideal, since metals are relatively thrombogenic and non- degradable. Moreover, metal stents may perforate the walls of the blood vessel.
An ideal stent, on the other hand, would be compatible in the biological system, i.e. compatible with blood, non- thrombogenic, not inducing any rejection reactions, and biodegradable, while any decomposition products would not be toxic.
The literature describes degradable intravascular stents which are manufactured from poly(L-lactide) . Poly(L- lactide) is a hydrolytically labile semi-crystalline aliphatic
polyester which is used in a large number of biomedical applications since the degradation product thereof, L-lactic acid, possesses a very minor toxicity. Recent developments, however, have shown that implantation of semi-crystalline poly(L-lactide) may eventually lead to a late tissue reaction because of the presence of small highly crystalline low- molecular poly(L-lactide) particles which are hydrolytically rather stable. These particles can be found at the site of implantation up to 5 years after implantation. The object of the invention is to provide an intravascular stent suitable for use in blood vessels after a Dotter therapy, which does not have the disadvantages of the above-described materials.
According to the invention, such an intravascular stent is manufactured from an amorphous, biocompatible polymer. Surprisingly, it has been found that amorphous biocompatible polymers are highly suitable for the manufacture of stents, without possessing the disadvantages of, for instance, the semi-crystalline pol (L-lactide) . A next advantage of such a polymeric stent resides in the fact that the material, after the cure of the blood vessel, which takes about three weeks, is absorbed by the body, since the material has no further function anymore.
The stent can be implanted in the blood vessel by a catheter as an elongated spiral of slight diameter. The stent is then thermally expanded to its original spiral shape. To make this possible, the polymeric material should have a glass transition temperature just below the body temperature. The material of the stents should therefore have a so-called thermal shape memory. A suitable stent can be manufactured by the in situ polymerization of suitable starting materials in a spiral-shaped matrix, for instance manufactured from PTFE. After polymerization, the spiral obtained can be stretched to any desired shape above the glass transition temperature of the material. This shape can be frozen after cooling to a temperature below the glass transition temperature. This makes it possible to introduce the stent into the blood vessel via a
catheter. After the stent has been introduced into the blood vessel, it can expand freely to the original spiral shape at body temperature. The closer to the body temperature the Tg of the polymeric material is, the faster the material wil l resume its original shape again. The expanding spiral then anchors itself in the blood vessel by exerting pressure on the wall of the blood vessel. It is therefore preferred to use a material which has a Tg between 0°C and 37°C.
In such situations, creep resistance is a particularly important property because it should be possible for the elongated spiral to expand completely to its original dimensions upon heating. A permanent deformation as a result of the elongation of the coil spring is undesirable. It has been found, however, that the use of polymeric (amorphous) networks as stent material gives an article of sufficient creep resistance. In practice this means that the creep of the material at body temperature is nil.
According to the invention, a large number of plastics are suitable for th> manufacture of the polymeric stent. The common feature of these polymers is that they are amorphous, cross-linked biologically active polymers, which are preferably also biodegradable. Examples of suitable groups of polymers are the amorphous non-crystallizable polylactic acid networks, the highly cross-linked polyurethane networks, which also includes the conversion products of star prepolyesters, for instance based on lactic acid copolymers, with diisocyanate. The extent of cross-linking should be such that the maximum gel content is obtained. Preferably, no unreacted low-molecular components are present. These polymers moreover have in common that they are sterilizable in the conventional manner with steam and that they meet the biocompatibility requirements given in the introduction (compatible with blood, non-thrombogenic, not causing any rejection reactions, biodegradable, while any decomposition products are non-toxic) .
The first group of polymers, amorphous non- crystallizable polylactic acid networks, comprises inter alia
the amorphous copolymers of lactides and glycolides, which have been converted to a network with suitable cross-linking agents. In view of the nature of the materials, cross-linking for the purpose of forming a network is preferably effected with a tetra- or higher functional cyclic ester, preferably with a tetrafunctional cyclic cross-linking agent such as biscaprolactone.
The second group of polymers, highly cross-linked polyurethane networks, is described inter alia in International patent application PCT/NL93/00203 filed 13 October 1993.
This group of polymers consists of cross-linked polyurethane networks obtainable by reacting one or more low- molecular polyols with a functionality of three or more and one or more polyisocyanates with a functionality of two or more in the absence of a solvent.
For obtaining suitable materials it is of importance that the polyols are low-molecular. In practice this means that the equivalent weight of the polyol is preferably 125 at a maximum. 'Equivalent weight' in this case is understood to mean the molecular weight per hydroxyl group. In general, the starting material is 3 or 4 functional polyols, although higher functionalities can be used as well. Practically, an upper limit lies at a functionality of 8. It is also possible, however, to include a minor amount of diols in the mixture.
However, since diols do not give rise to cross-linking, either the amount thereof should be kept low or one should work with substantially 3 or higher functional isocyanates . In general, the number of hydroxyl groups coming from a diol will be less than about 10% of the total number of hydroxyl groups. Preferred polyols are selected from the group consisting of triethanolamine (TEA), tri-isopropanolamine, 1,1,1, -trimethylol-propane (TMP) , N,N,N' ,N' -tetrakis (2- hydroxypropy1) -ethylenediamine (Quadrol) , octakis(2- hydroxypropyl) penta-erytrytyltetra-amine, tetrakis{β- hydroxyethyl}methane, 1,1,1 trihydroxyethylpropane, 1,1,1 trihydroxyethylethane and other polyols. It is also
possible to use modified or unmodified pentaerytritol or inositol.
The polyisocyanates which can be used according to this embodiment of the invention are the conventional diisocyanates and higher isocyanates, for instance selected from the group consisting of butanediisocyanate, hexamethylene diisocyanate, dodecane diisocyanate, trans 1,4-cyclohexane diisocyanate, methylene dicyclohexane diisocyanate, lysine di- or triisocyanate, isophorone diisocyanate, p-phenylene diisocyanate, methylene diphenyl diisocyanate, triphenyl- methanetriisocyanate, thiophosphoric acid tris(4-isocyanati- phenyl ester), polymeric methylene diphenyl diisocyanate as well as trimerization products and adducts of these isocyanates, for instance based on polyols. Examples of suitable polyols have been given hereinabove.
The third product group comprises the conversion products of star prepolyesters and a di-isocyanate, preferably a di-isocyanate based on an L-lysine derivative or on 1,4-diisocyanatobutane. A number of these products are described inter alia in International patent application PCT/NL 88/00060, incorporated herei* y reference.
According to this variant oi the invention, as diisocyanate, preferably a lysine derivative is used having one of the formulae 1-3 of the sheet of formulae, or 1,4-diisocyanatobutane. These isocyanates are reacted with suitable polyols, such as polyester polyols based on lactide, glycolide, and/or lactones such as ε-caprolactone or δ-valerolactone. Such a polyester can be initiated with a suitable low-molecular polyol, such as glycol, pentaerytritol, myo-inositol and the like.
In the case where it is desirable that the material of the polymeric stent is broker down in the body, it is preferred to manufacture the polymer from polymers whose decomposition products are not toxic. Although the three groups of polymers described hereinabove are highly suitable as such, it may be desirable, in order to obtain the desirable strength properties, that a
second phase be incorporated into the material, for instance by the introduction of one or more fillers, fibers and/or a second polymeric phase. In particular by incorporating a second polymeric phase, in the form of a separate rubber phase, materials are obtained which possess a particularly good combination of mechanical properties.
The invention will now be elucidated in and by a few examples which should not be construed as limiting.
Example 1
Cross-linked poly(lactide-ε-caprolactone;80/20 mole ratio) was manufactured by in situ polymerization in a spiral- shaped PTFE mold. The monomer mixture, the cross-linking agent (5, 5 ' -bis(oxepan-2-one) ) and the catalyst, tin octoate
(monomer-catalyst ratio 1000 based on weight) were introduced into a silanized glass ampoule and melted and homogenized at 130°C. Then the mold, also disposed in the ampoule, was filled with the molten mixture by allowing it to fill up under the influence of gravity. The polymerization was carried out at
130°C for 90 hours. Upon completion of the polymerization the stent obtained could easily be removed from the mold.
Example 2
A stent was manufactured from a highly cross-linked polyurethane network, using a PTFE mold. The starting materials, triethanolamine, tetrakis(2-hydroxypropyl) - ethylenediamine and hexamethylenediisocyanate, were purified by distillation at reduced pressure. The components were then mixed and degassed a number of times. With a syringe the mixture was introduced into the mold and gelled at room temperature. Then curing was allowed to take place for 24 hours at about 100°C, whereafter the stent was removed from the mold.
Re s ults
The mechanical properties of a number of stents manufactured according to Examples 1 and 2 are included in the following table and figures.
Table 1 mechanical properties of polyester and polyurethane networks at different temperatures
T Tensile Young's elongation toughness Tg strength modulus at break
°C MPa MPa % MPa °C
1 40 21 21 450 25 32
2 40 17 57 96 7 23
3 24 60* 1200 26 14 70
4 80 10 21 50 2 70
5 80 10 21 50 2 73
1: poly(lactide-co-ε-caprolactone) , 80/20 mole %, cross- linked with 5,5' -bis(oxepan-2-one)
2: TEA/Quadrol(40: 60)/HDI PU network after water uptake
3,4: TEA/Quadrol(40:60)/HDI PU network
5: TEA/Quadrol(20:80)/HDI PU network *: Yield stress:71 MPa
Claims
1. A polymeric stent manufactured from an amorphous, biocompatible and cross-linked polymer.
2. A stent according to claim 1, manufactured from a polymer having a shape memory at body temperature.
3. A stent according to claim 1 or 2, manufactured from a polymer selected from the group consisting of amorphous, non-crystallizable polylactic acid networks, highly cross- linked polyurethane networks and conversion products of star prepolyesters and di-isocyanate.
4. A stent according to claim 2, manufactured from polylactide copolyester cross-linked with a di-functional cyclic ester.
5. A stent according to claim 4, manufactured from a pol (lactide-ε-caprolactone) cross-linked with biscaprolactone.
6. A stent according to claim 3, manufactured from a polyurethane network obtained by polymerizing a suitable polyol, preferably a triol or a tetra-ol and a suitable polyisocyanate, preferably a diisocyanate, in the absence of solvents.
7. A stent according to claims 1-6, manufactured from a polyphase polymer.
8. A stent according to claim 7, manufactured from a polymer comprising one or more fillers, fibers and/or a second, preferably amorphous, polymeric phase.
9. A biomedical aid manufactured from an amorphous, biocompatible and cross-linked polymer having a shape memory at body temperature.
10. A method for manufacturing a stent or a biomedical aid according to claims 1-9, comprising polymerizing the starting materials for the polymer in a spiral-shaped mold, followed by removing the obtained article from the mold.
11. A method according to claim 10, wherein the mold is manufactured from polytetrafluoroethene.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL9400519 | 1994-03-31 | ||
NL9400519A NL9400519A (en) | 1994-03-31 | 1994-03-31 | Intravascular polymeric stent. |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1995026762A1 true WO1995026762A1 (en) | 1995-10-12 |
Family
ID=19864019
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/NL1995/000122 WO1995026762A1 (en) | 1994-03-31 | 1995-03-30 | Intravascular polymeric stent |
Country Status (2)
Country | Link |
---|---|
NL (1) | NL9400519A (en) |
WO (1) | WO1995026762A1 (en) |
Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1997011725A1 (en) * | 1995-09-27 | 1997-04-03 | Biocon Oy | Under tissue conditions degradable material and a method for its manufacturing |
US5962007A (en) * | 1997-12-19 | 1999-10-05 | Indigo Medical, Inc. | Use of a multi-component coil medical construct |
US6001117A (en) * | 1998-03-19 | 1999-12-14 | Indigo Medical, Inc. | Bellows medical construct and apparatus and method for using same |
US6206883B1 (en) | 1999-03-05 | 2001-03-27 | Stryker Technologies Corporation | Bioabsorbable materials and medical devices made therefrom |
WO2002041929A1 (en) * | 2000-11-21 | 2002-05-30 | Schering Ag | Tubular vascular implants (stents) and methods for producing the same |
US6747121B2 (en) | 2001-09-05 | 2004-06-08 | Synthes (Usa) | Poly(L-lactide-co-glycolide) copolymers, methods for making and using same, and devices containing same |
US7087078B2 (en) | 2000-11-21 | 2006-08-08 | Schering Ag | Tubular vascular implants (stents) and methods for producing the same |
US7091297B2 (en) | 2002-10-11 | 2006-08-15 | The University Of Connecticut | Shape memory polymers based on semicrystalline thermoplastic polyurethanes bearing nanostructured hard segments |
WO2006098757A3 (en) * | 2004-08-16 | 2006-11-16 | Univ California | Shape memory polymers |
US7173096B2 (en) | 2002-10-11 | 2007-02-06 | University Of Connecticut | Crosslinked polycyclooctene |
US7208550B2 (en) | 2002-10-11 | 2007-04-24 | The University Of Connecticut | Blends of amorphous and semicrystalline polymers having shape memory properties |
US7524914B2 (en) | 2002-10-11 | 2009-04-28 | The University Of Connecticut | Shape memory polymers based on semicrystalline thermoplastic polyurethanes bearing nanostructured hard segments |
US8048980B2 (en) | 2007-09-17 | 2011-11-01 | Bezwada Biomedical, Llc | Hydrolysable linkers and cross-linkers for absorbable polymers |
WO2012109535A2 (en) | 2011-02-11 | 2012-08-16 | Bezwada Biomedical, Llc | Amino acid derivatives and absorbable polymers therefrom |
US8367747B2 (en) | 2008-05-23 | 2013-02-05 | Bezwada Biomedical, Llc | Bioabsorbable polymers from bioabsorbable polyisocyanates and uses thereof |
US8449903B2 (en) | 2009-06-08 | 2013-05-28 | Boston Scientific Scimed, Inc. | Crosslinked bioabsorbable medical devices |
US9034356B2 (en) | 2006-01-19 | 2015-05-19 | Warsaw Orthopedic, Inc. | Porous osteoimplant |
US9115245B2 (en) | 2002-10-11 | 2015-08-25 | Boston Scientific Scimed, Inc. | Implantable medical devices |
US9173973B2 (en) | 2006-07-20 | 2015-11-03 | G. Lawrence Thatcher | Bioabsorbable polymeric composition for a medical device |
US9211205B2 (en) | 2006-10-20 | 2015-12-15 | Orbusneich Medical, Inc. | Bioabsorbable medical device with coating |
US9328192B2 (en) | 2014-03-12 | 2016-05-03 | Bezwada Biomedical, Llc | Bio-based monomers and polymers |
US9724864B2 (en) | 2006-10-20 | 2017-08-08 | Orbusneich Medical, Inc. | Bioabsorbable polymeric composition and medical device |
US9745402B2 (en) | 2004-08-16 | 2017-08-29 | Lawrence Livermore National Security, Llc | Shape memory polymers |
US11820852B2 (en) | 2004-08-16 | 2023-11-21 | Lawrence Livermore National Security, Llc | Shape memory polymers |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1989005830A1 (en) * | 1987-12-23 | 1989-06-29 | Stichting Biomat | Biodegradable polyurethanes, products based thereon, and polyester polyol prepolymers |
EP0326426A2 (en) * | 1988-01-28 | 1989-08-02 | JMS Co., Ltd. | Plastic molded articles with shape memory property |
EP0420541A2 (en) * | 1989-09-27 | 1991-04-03 | Bristol-Myers Squibb Company | Biodegradable stent |
EP0428479A1 (en) * | 1989-11-01 | 1991-05-22 | Schneider (Europe) Ag | Stent and catheter for inserting the stent |
EP0460439A2 (en) * | 1990-06-07 | 1991-12-11 | American Cyanamid Company | Deformable surgical device |
WO1992004393A1 (en) * | 1990-09-10 | 1992-03-19 | Rijksuniversiteit Te Groningen | METHOD FOR THE PRODUCTION OF COPOLYMERS OF LACTIDE AND ε-CAPROLACTONE AND ARTICLES THEREOF FOR MEDICAL APPLICATIONS |
WO1993015787A1 (en) * | 1992-02-12 | 1993-08-19 | Chandler Jerry W | Biodegradable stent |
-
1994
- 1994-03-31 NL NL9400519A patent/NL9400519A/en not_active Application Discontinuation
-
1995
- 1995-03-30 WO PCT/NL1995/000122 patent/WO1995026762A1/en active Application Filing
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1989005830A1 (en) * | 1987-12-23 | 1989-06-29 | Stichting Biomat | Biodegradable polyurethanes, products based thereon, and polyester polyol prepolymers |
EP0326426A2 (en) * | 1988-01-28 | 1989-08-02 | JMS Co., Ltd. | Plastic molded articles with shape memory property |
EP0420541A2 (en) * | 1989-09-27 | 1991-04-03 | Bristol-Myers Squibb Company | Biodegradable stent |
EP0428479A1 (en) * | 1989-11-01 | 1991-05-22 | Schneider (Europe) Ag | Stent and catheter for inserting the stent |
EP0460439A2 (en) * | 1990-06-07 | 1991-12-11 | American Cyanamid Company | Deformable surgical device |
WO1992004393A1 (en) * | 1990-09-10 | 1992-03-19 | Rijksuniversiteit Te Groningen | METHOD FOR THE PRODUCTION OF COPOLYMERS OF LACTIDE AND ε-CAPROLACTONE AND ARTICLES THEREOF FOR MEDICAL APPLICATIONS |
WO1993015787A1 (en) * | 1992-02-12 | 1993-08-19 | Chandler Jerry W | Biodegradable stent |
Non-Patent Citations (1)
Title |
---|
P. BRUIN ET AL.: "AUTOCLAVABLE HIGHLY CROSS-LINKED POLYURETHANE NETWORKS IN OPHTHALMOLOGY.", BIOMATERIALS, vol. 14, no. 14, November 1993 (1993-11-01), pages 1089 - 1097 * |
Cited By (39)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1997011725A1 (en) * | 1995-09-27 | 1997-04-03 | Biocon Oy | Under tissue conditions degradable material and a method for its manufacturing |
AU729801B2 (en) * | 1995-09-27 | 2001-02-08 | Biocon Oy | Under tissue conditions degradable material and a method for its manufacturing |
US6503278B1 (en) | 1995-09-27 | 2003-01-07 | Bionx Implants Oy | Under tissue conditions degradable material and a method for its manufacturing |
US5962007A (en) * | 1997-12-19 | 1999-10-05 | Indigo Medical, Inc. | Use of a multi-component coil medical construct |
AU741985B2 (en) * | 1997-12-19 | 2001-12-13 | Indigo Medical, Incorporated | Use of a multi-component coil medical construct |
US6001117A (en) * | 1998-03-19 | 1999-12-14 | Indigo Medical, Inc. | Bellows medical construct and apparatus and method for using same |
US6206883B1 (en) | 1999-03-05 | 2001-03-27 | Stryker Technologies Corporation | Bioabsorbable materials and medical devices made therefrom |
US6716957B2 (en) | 1999-03-05 | 2004-04-06 | Stryker Technologies Corporation | Bioabsorbable materials and medical devices made therefrom |
WO2002041929A1 (en) * | 2000-11-21 | 2002-05-30 | Schering Ag | Tubular vascular implants (stents) and methods for producing the same |
US7087078B2 (en) | 2000-11-21 | 2006-08-08 | Schering Ag | Tubular vascular implants (stents) and methods for producing the same |
US6747121B2 (en) | 2001-09-05 | 2004-06-08 | Synthes (Usa) | Poly(L-lactide-co-glycolide) copolymers, methods for making and using same, and devices containing same |
US7705098B2 (en) | 2002-10-11 | 2010-04-27 | University Of Connecticut | Crosslinked polycyclooctene |
US7091297B2 (en) | 2002-10-11 | 2006-08-15 | The University Of Connecticut | Shape memory polymers based on semicrystalline thermoplastic polyurethanes bearing nanostructured hard segments |
US7173096B2 (en) | 2002-10-11 | 2007-02-06 | University Of Connecticut | Crosslinked polycyclooctene |
US7208550B2 (en) | 2002-10-11 | 2007-04-24 | The University Of Connecticut | Blends of amorphous and semicrystalline polymers having shape memory properties |
US7371799B2 (en) | 2002-10-11 | 2008-05-13 | University Of Connecticut | Blends of amorphous and semicrystalline polymers having shape memory properties |
US7524914B2 (en) | 2002-10-11 | 2009-04-28 | The University Of Connecticut | Shape memory polymers based on semicrystalline thermoplastic polyurethanes bearing nanostructured hard segments |
US7563848B2 (en) | 2002-10-11 | 2009-07-21 | University Of Connecticut | Crosslinked polycyclooctene |
US9115245B2 (en) | 2002-10-11 | 2015-08-25 | Boston Scientific Scimed, Inc. | Implantable medical devices |
US7795350B2 (en) | 2002-10-11 | 2010-09-14 | Connecticut, University Of | Blends of amorphous and semicrystalline polymers having shape memory properties |
US7906573B2 (en) | 2002-10-11 | 2011-03-15 | University Of Connecticut | Crosslinked polycyclooctene |
US11820852B2 (en) | 2004-08-16 | 2023-11-21 | Lawrence Livermore National Security, Llc | Shape memory polymers |
US11453740B2 (en) | 2004-08-16 | 2022-09-27 | Lawrence Livermore National Security, Llc | Shape memory polymers |
US10526437B2 (en) | 2004-08-16 | 2020-01-07 | Lawrence Livermore National Security, Llc | Shape memory polymers |
US9745402B2 (en) | 2004-08-16 | 2017-08-29 | Lawrence Livermore National Security, Llc | Shape memory polymers |
WO2006098757A3 (en) * | 2004-08-16 | 2006-11-16 | Univ California | Shape memory polymers |
US9034356B2 (en) | 2006-01-19 | 2015-05-19 | Warsaw Orthopedic, Inc. | Porous osteoimplant |
US9173973B2 (en) | 2006-07-20 | 2015-11-03 | G. Lawrence Thatcher | Bioabsorbable polymeric composition for a medical device |
US9211205B2 (en) | 2006-10-20 | 2015-12-15 | Orbusneich Medical, Inc. | Bioabsorbable medical device with coating |
US9724864B2 (en) | 2006-10-20 | 2017-08-08 | Orbusneich Medical, Inc. | Bioabsorbable polymeric composition and medical device |
US9045396B2 (en) | 2007-09-17 | 2015-06-02 | Bezwada Biomedical, Llc | Hydrolysable linkers and cross-linkers for absorbable polymers |
US8664429B2 (en) | 2007-09-17 | 2014-03-04 | Bezwada Biomedical, Llc | Hydrolysable linkers and cross-linkers for absorbable polymers |
US9174924B2 (en) | 2007-09-17 | 2015-11-03 | Bezwada Biomedical, Llc | Hydrolysable linkers and cross-linkers for absorbable polymers |
US8048980B2 (en) | 2007-09-17 | 2011-11-01 | Bezwada Biomedical, Llc | Hydrolysable linkers and cross-linkers for absorbable polymers |
US8551519B2 (en) | 2008-05-23 | 2013-10-08 | Bezwada Biomedical, Llc | Bioabsorbable surgical articales or components thereof |
US8367747B2 (en) | 2008-05-23 | 2013-02-05 | Bezwada Biomedical, Llc | Bioabsorbable polymers from bioabsorbable polyisocyanates and uses thereof |
US8449903B2 (en) | 2009-06-08 | 2013-05-28 | Boston Scientific Scimed, Inc. | Crosslinked bioabsorbable medical devices |
WO2012109535A2 (en) | 2011-02-11 | 2012-08-16 | Bezwada Biomedical, Llc | Amino acid derivatives and absorbable polymers therefrom |
US9328192B2 (en) | 2014-03-12 | 2016-05-03 | Bezwada Biomedical, Llc | Bio-based monomers and polymers |
Also Published As
Publication number | Publication date |
---|---|
NL9400519A (en) | 1995-11-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO1995026762A1 (en) | Intravascular polymeric stent | |
US9540478B2 (en) | Biodegradable polyurethane and polyurethane ureas | |
AU2008307139B2 (en) | High modulus polyurethane and polyurethane/urea compositions | |
US6784273B1 (en) | Biomedical polyurethane, its preparation and use | |
US20090299465A1 (en) | Absorbable / biodegradable tubular stent and methods of making the same | |
WO2007126598A2 (en) | Degradable polymeric implantable medical devices with a continuous phase and discrete phase | |
CN103705986A (en) | Degradable vascular stent, and manufacturing method thereof | |
US9840593B2 (en) | Phase segregated block copolymers with tunable properties | |
JP3012442B2 (en) | Impact resistant polyurethane | |
WO2009158290A2 (en) | Implantable medical devices fabricated from radiopaque polymers with high fracture toughness | |
KR102407468B1 (en) | Biodegradable composite material composition for manufacturing stent and manufacturing method thereof | |
Maafi et al. | Synthesis and characterization of new polyurethanes: influence of monomer composition | |
AU2005223917B2 (en) | Biodegradable polyurethane and polyurethane ureas | |
LIANG | Designing and Synthesis of Shape-Memory Polymers for Biomedical Application | |
JP2008120888A (en) | Biodegradable copolymer and method for producing the same | |
Wnek et al. | Elastomers, Biodegradable/John J. Stankus, Jianjun Guan, William R. Wagner |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): FI JP US |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
122 | Ep: pct application non-entry in european phase |