WO2003039407A2 - Method for manufacturing a stent - Google Patents

Method for manufacturing a stent Download PDF

Info

Publication number
WO2003039407A2
WO2003039407A2 PCT/GB2002/005076 GB0205076W WO03039407A2 WO 2003039407 A2 WO2003039407 A2 WO 2003039407A2 GB 0205076 W GB0205076 W GB 0205076W WO 03039407 A2 WO03039407 A2 WO 03039407A2
Authority
WO
WIPO (PCT)
Prior art keywords
stent
powder
manufacturing
laser
set forth
Prior art date
Application number
PCT/GB2002/005076
Other languages
French (fr)
Other versions
WO2003039407A3 (en
Inventor
Denis Dominic Healy
Original Assignee
Biocompatibles Limited
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 Biocompatibles Limited filed Critical Biocompatibles Limited
Priority to AU2002339126A priority Critical patent/AU2002339126A1/en
Publication of WO2003039407A2 publication Critical patent/WO2003039407A2/en
Publication of WO2003039407A3 publication Critical patent/WO2003039407A3/en

Links

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS 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
    • A61F2/00Filters 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
    • A61F2/82Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
    • A61F2/90Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure
    • A61F2/91Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS 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
    • A61F2/00Filters 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
    • A61F2/82Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
    • A61F2/90Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure
    • A61F2/91Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
    • A61F2/915Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C10/00Solid state diffusion of only metal elements or silicon into metallic material surfaces
    • C23C10/28Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes
    • C23C10/30Solid state diffusion of only metal elements or silicon into metallic material surfaces using solids, e.g. powders, pastes using a layer of powder or paste on the surface
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C24/00Coating starting from inorganic powder
    • C23C24/02Coating starting from inorganic powder by application of pressure only
    • C23C24/04Impact or kinetic deposition of particles
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS 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
    • A61F2/00Filters 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
    • A61F2/82Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
    • A61F2/90Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure
    • A61F2/91Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
    • A61F2/915Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other
    • A61F2002/91525Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other within the whole structure different bands showing different meander characteristics, e.g. frequency or amplitude
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS 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
    • A61F2/00Filters 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
    • A61F2/82Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
    • A61F2/90Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure
    • A61F2/91Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
    • A61F2/915Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other
    • A61F2002/91533Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other characterised by the phase between adjacent bands
    • A61F2002/91541Adjacent bands are arranged out of phase
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS 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
    • A61F2/00Filters 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
    • A61F2/82Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
    • A61F2/90Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure
    • A61F2/91Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
    • A61F2/915Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other
    • A61F2002/9155Adjacent bands being connected to each other
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS 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
    • A61F2/00Filters 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
    • A61F2/82Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
    • A61F2/90Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure
    • A61F2/91Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
    • A61F2/915Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other
    • A61F2002/9155Adjacent bands being connected to each other
    • A61F2002/91558Adjacent bands being connected to each other connected peak to peak

Definitions

  • the present invention relates generally to a manufacturing process for stents and stents formed by the manufacturing process, and in particular to methods and stents formed therefrom having increased radiopacity.
  • a stent is a medical device, usually a hollow tubular structure, which is inserted into a body lumen to provide support thereto.
  • Stents are well known in the art and there are many different types of stents available. Some are configured to be expanded after being located at a desired position in the lumen by an expansive force provided by an inflatable balloon. Others are delivered under compression so that, upon delivery they expand to provide the necessary supporting force. Others are made from heat-sensitive materials that expand at body temperature to provide the necessary supportive force. In recent times there has been a desire to form such stents from smaller and smaller quantities of material to provide greater flexibility, i.e., so that they are more flexible prior to delivery.
  • the present invention seeks to provide a method, and a stent produced therefrom, which increases the radiopacity of the stent without causing some of the problems associated with previous attempts at increasing radiopacity.
  • a method of manufacturing a stent 0 formed from a metal or metal alloy including the steps of applying a powder of a material having a higher radiopacity than that of the material from which the stent is formed to a region of the surface of the stent, and applying laser light to the surface having the radiopaque powder placed thereon such that the surface melts to incorporate the powder.
  • the preferred embodiment of the method may include the step of forming the 5 stent from stainless steel.
  • the powder may be formed from gold, platinum, tantalum, niobium, titanium or tungsten or a combination thereof.
  • the powder may be applied at the same time as applying the laser light.
  • the powder may also be applied by cold gas dynamic spraying.
  • the laser light may be generated by a YAG laser, a CO 2 laser, a Diode laser or Femto 0 laser.
  • the method may also include the step of cutting holes in the stent using the same laser either before or after fixing the powder to the surface of the stent.
  • the laser light may be applied to the powder at least twice in order to smooth the surface profile of the end product.
  • the present invention also may be used to manufacture a stent formed from a metal or
  • the stent having a powder impregnated in the surface thereof and the power being formed from a material having a radiopacity greater than that of the metal or metal alloy.
  • the stent of the present invention manufactured by applying a powder of a material having a higher radiopacity than that of the material from which the stent is formed to a region of the surface of the stent and applying laser light to the surface having the radiopaque powder
  • the powder is selected from the group including gold, platinum, tantalum, niobium, titanium or tungsten or a combination thereof.
  • Figure 1 is a side view of a known stent
  • Figure 2 is a side view of a stent manufactured in accordance with the present invention
  • FIGS 3A and 3B are schematic diagrams of the steps of the method of the present invention.
  • Figures 4A-4C are a series of images of the surface of stents produced in accordance with the method of the present invention.
  • a known stent 1 is shown.
  • the stent 1 has a body portion formed from a hollow tube of metal or metal alloy, usually stainless steel, as is well known in the art with cuts or openings in the surface of the stent 1 in a series of holes 2 which define struts 3.
  • the stent shown is a balloon-expandable stent 1 and the struts 3 are shaped so that, when a balloon 5 is inserted into the stent 1 and expanded, the stent 1 expands to form a rigid structure that can support a body lumen.
  • FIG. 2 shows a stent 1 according to the present invention in which components that correspond to those in the known stent 1 of figure 1 are numbered identically.
  • the stent 1 according to the invention has regions 4 of higher radiopacity 4 bonded on struts 3 at either end of the structure of the stent 1. These regions 4 of higher radiopacity enhance the visibility of the stent 1 under x-ray imaging so that, either during deployment or after deployment, a surgeon can more easily view the location of the stent 1.
  • Figure 3 A illustrates a preferred embodiment of the method of the present invention at various stages in the process of manufacturing the stent 1 of Figure 2.
  • a hollow tube of metal such as stainless steel, is provided with holes 2 etched or cut therein with a laser 6 which may be a YAG laser or, more cost effectively, a CO 2 laser.
  • Powdered radiopaque material is then applied either manually or automatically to at least a portion of the struts 3 at either end of the stent 1.
  • Laser light either from a separate laser light source or the same laser light source 6 that carried out the etching, is then applied so as to either melt the powder, or the surface of the struts 3, or both, when the light is applied in order to impregnate the surface of the stent 1 with the powder to form a radiopaque region 4.
  • the process is repeated in order to provide sufficient number of radiopaque regions 4 to ensure good visibility of the stent 1 in use.
  • the laser 6 may be applied a second time in order to smooth the overall surface.
  • Figure 3B illustrated another embodiment of the method of the present invention.
  • the powder is applied simultaneously with the laser light application.
  • This may involve use of a laser light source 6 with a surrounding powder dispensing nozzle 7 or a separate nozzle 7, both of which are shown in the figure.
  • the speed of the particles of the powder will preferably be in the range of 0.1 to 20m per second, providing flow rate for the powder particles which will be in the region of 1 to 1000 ⁇ g per second.
  • the powder is fed with an inert gas such as argon, helium or nitrogen.
  • the laser may be applied a second time, during which powder is not fed to the surface of the stent.
  • the method may employ one of a number of types of lasers, and in general it would be expected that the power of the laser would be no more than 50 Watts.
  • the method of the invention may be employed using a YAG welding laser with a Nb-Ti alloy powder, and Figure 4A shows a radiopaque region formed by such an approach.
  • a 250 am wide line of radiopaque region is formed which rises about 15 to 20 ⁇ m from of the surface of the stent 1.
  • the laser light was applied as spots which overlapped, and a higher repetition of the spots can increase the smoothness of the applied radiopaque region as can be seen from Figure 4B.
  • Figure 4C shows how the radiopaque region of Figure 4B can be further smoothed by passing the laser light over the region for a second time.

Abstract

A method of manufacturing a stent formed from a metal or metal alloy includes the steps of applying a powder of a material having a higher radiopacity than that of the material from which the stent is formed to a region of the surface of the stent, and applying laser light to the surface having the radiopaque powder placed thereon so that the powder is incorporated into the surface of the stent. The method may also include forming said stent from stainless steel. In addition, the powder may be selected from the group including gold, platinum, tantalum, niobium, titanium, or tungsten or a combination thereof and the laser light may be generated by a YAG laser, a CO2 laser, a Diode laser or a Femto laser. Alternatively, a stent may be provided formed from a metal or metal alloy with the stent having the powder impregnated in the surface thereof.

Description

METHOD FOR MANUFACTURING A STENT
FIELD OF THE INVENTION The present invention relates generally to a manufacturing process for stents and stents formed by the manufacturing process, and in particular to methods and stents formed therefrom having increased radiopacity.
BACKGROUND OF THE INVENTION A stent is a medical device, usually a hollow tubular structure, which is inserted into a body lumen to provide support thereto. Stents are well known in the art and there are many different types of stents available. Some are configured to be expanded after being located at a desired position in the lumen by an expansive force provided by an inflatable balloon. Others are delivered under compression so that, upon delivery they expand to provide the necessary supporting force. Others are made from heat-sensitive materials that expand at body temperature to provide the necessary supportive force. In recent times there has been a desire to form such stents from smaller and smaller quantities of material to provide greater flexibility, i.e., so that they are more flexible prior to delivery. There has also been a desire to produce stents for smaller lumens. Whilst such stents are often made from materials which are radiopaque, this desire for reduced amounts of material in the stents has led to the stents becoming less radiopaque and, as such, difficult to see under X- ray either during or after deployment.
Attempts have been made to overcome this lack of visibility problem by attaching to the stent pieces of radiopaque material, such as gold. Doing this introduces problems, however, in that it increases the overall bulk of the stent, making it difficult to produce for insertion into small lumens, and reducing its flexibility. It is also difficult to handle the very small pieces of radiopaque material, making manufacture difficult and unreliable. There is also the risk that the attached radiopaque component may detach itself in the body, potentially causing a serious health risk. An alternative approach has been to coat the stent with radiopaque material, again such as gold, in order to increase radiopacity. However, this approach is difficult because of the complexity of the coating processes and because a failure to coat correctly can lead to problems, such as galvanic corrosion. 5 SUMMARY OF THE INVENTION
The present invention seeks to provide a method, and a stent produced therefrom, which increases the radiopacity of the stent without causing some of the problems associated with previous attempts at increasing radiopacity.
According to the present invention there is provided a method of manufacturing a stent 0 formed from a metal or metal alloy, with the method including the steps of applying a powder of a material having a higher radiopacity than that of the material from which the stent is formed to a region of the surface of the stent, and applying laser light to the surface having the radiopaque powder placed thereon such that the surface melts to incorporate the powder.
In addition, the preferred embodiment of the method may include the step of forming the 5 stent from stainless steel. Also, the powder may be formed from gold, platinum, tantalum, niobium, titanium or tungsten or a combination thereof.
The powder may be applied at the same time as applying the laser light. The powder may also be applied by cold gas dynamic spraying.
The laser light may be generated by a YAG laser, a CO2 laser, a Diode laser or Femto 0 laser. The method may also include the step of cutting holes in the stent using the same laser either before or after fixing the powder to the surface of the stent.
The laser light may be applied to the powder at least twice in order to smooth the surface profile of the end product.
The present invention also may be used to manufacture a stent formed from a metal or
.5 metal alloy, with the stent having a powder impregnated in the surface thereof and the power being formed from a material having a radiopacity greater than that of the metal or metal alloy.
The stent of the present invention, manufactured by applying a powder of a material having a higher radiopacity than that of the material from which the stent is formed to a region of the surface of the stent and applying laser light to the surface having the radiopaque powder
\0 placed thereon so that the powder is incorporated into the surface of the stent, includes a body portion having an outer surface with a powder having a higher radiopacity than that of the material from which the stent is formed incorporated into at least a portion of the surface of the stent. In the preferred embodiment of the stent, the powder is selected from the group including gold, platinum, tantalum, niobium, titanium or tungsten or a combination thereof. BRIEF DESCRIPTION OF THE DRAWINGS
Other advantages of the present invention will be readily appreciated and apparent to those skilled in the art as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which:
Figure 1 is a side view of a known stent; Figure 2 is a side view of a stent manufactured in accordance with the present invention;
Figures 3A and 3B are schematic diagrams of the steps of the method of the present invention; and
Figures 4A-4C are a series of images of the surface of stents produced in accordance with the method of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to figure 1, a known stent 1 is shown. The stent 1 has a body portion formed from a hollow tube of metal or metal alloy, usually stainless steel, as is well known in the art with cuts or openings in the surface of the stent 1 in a series of holes 2 which define struts 3. The stent shown is a balloon-expandable stent 1 and the struts 3 are shaped so that, when a balloon 5 is inserted into the stent 1 and expanded, the stent 1 expands to form a rigid structure that can support a body lumen. It will be appreciated that, whilst the method of the present invention is described with reference to such a balloon-expandable stent 1, the teaching herein could equally be applied to other types of stent, such as those which are constructed to be self-expanding either due to the forces formed within the stent or through being formed from a heat-sensitive material such as nitinol.
Figure 2 shows a stent 1 according to the present invention in which components that correspond to those in the known stent 1 of figure 1 are numbered identically. As can be seen from this figure, the stent 1 according to the invention has regions 4 of higher radiopacity 4 bonded on struts 3 at either end of the structure of the stent 1. These regions 4 of higher radiopacity enhance the visibility of the stent 1 under x-ray imaging so that, either during deployment or after deployment, a surgeon can more easily view the location of the stent 1.
Figure 3 A illustrates a preferred embodiment of the method of the present invention at various stages in the process of manufacturing the stent 1 of Figure 2. Initially, a hollow tube of metal, such as stainless steel, is provided with holes 2 etched or cut therein with a laser 6 which may be a YAG laser or, more cost effectively, a CO2 laser. Powdered radiopaque material is then applied either manually or automatically to at least a portion of the struts 3 at either end of the stent 1. Laser light, either from a separate laser light source or the same laser light source 6 that carried out the etching, is then applied so as to either melt the powder, or the surface of the struts 3, or both, when the light is applied in order to impregnate the surface of the stent 1 with the powder to form a radiopaque region 4. The process is repeated in order to provide sufficient number of radiopaque regions 4 to ensure good visibility of the stent 1 in use. The laser 6 may be applied a second time in order to smooth the overall surface.
Figure 3B illustrated another embodiment of the method of the present invention. In this embodiment, the powder is applied simultaneously with the laser light application. This may involve use of a laser light source 6 with a surrounding powder dispensing nozzle 7 or a separate nozzle 7, both of which are shown in the figure. In this case, the speed of the particles of the powder will preferably be in the range of 0.1 to 20m per second, providing flow rate for the powder particles which will be in the region of 1 to 1000 μg per second. Preferably, the powder is fed with an inert gas such as argon, helium or nitrogen. Again, the laser may be applied a second time, during which powder is not fed to the surface of the stent. h both embodiments, the method may employ one of a number of types of lasers, and in general it would be expected that the power of the laser would be no more than 50 Watts.
The method of the invention may be employed using a YAG welding laser with a Nb-Ti alloy powder, and Figure 4A shows a radiopaque region formed by such an approach. A 250 am wide line of radiopaque region is formed which rises about 15 to 20 μm from of the surface of the stent 1. The laser light was applied as spots which overlapped, and a higher repetition of the spots can increase the smoothness of the applied radiopaque region as can be seen from Figure 4B. Figure 4C shows how the radiopaque region of Figure 4B can be further smoothed by passing the laser light over the region for a second time.
The description given above provides example of various embodiments for implementing the method of the present invention and the stent produced therefrom. Variations and modifications may become apparent to those skilled in the art that do not necessarily depart from the basis of this invention. The scope of legal protection given to this invention can only be determined by studying the following claims.

Claims

CLAIMSWhat is claimed is:
1. A method of manufacturing a stent formed from a metal or metal alloy comprising the steps of: applying a powder of a material having a higher radiopacity than that of the material from which the stent is formed to a region of the surface of the stent; and applying laser light to the surface having the radiopaque powder placed thereon so that the powder is incorporated into the surface of the stent.
2. The method of manufacturing a stent set forth in Claim 1, further comprising the step of forming said stent from stainless steel.
3. The method of manufacturing a stent set forth in Claim 1, wherein said powder is selected from the group including gold, platinum, tantalum, niobium, titanium or tungsten or a combination thereof.
4. The method of manufacturing a stent set forth in Claim 1, wherein the steps of applying the powder and applying the laser light may be undertaken simultaneously.
5. The method of manufacturing a stent set forth in Claim 1 , wherein the powder may be applied by cold gas dynamic spraying.
6. The method of manufacturing a stent set forth in Claim 1 , wherein the laser light may be generated by a YAG laser, a CO2 laser, a Diode laser or a Femto laser.
7. The method of manufacturing a stent set forth in Claim 1, further comprising the step of cutting holes in the stent using the same laser either before or after fixing the powder to the surface of the stent.
8. The method of manufacturing a stent set forth in Claim 1 , wherein the laser light may be applied to the powder at least twice in order to smooth the surface profile of the stent.
5 9. A memod of manufacturing a stent formed from a metal or metal alloy comprising the steps of: providing a stent formed from a metal or metal alloy with the stent having a powder impregnated in the surface thereof and the powder being formed from a material having a radiopacity greater than that of the metal or metal alloy; and 0 applying laser light to the surface having the radiopaque powder placed thereon so that the surface melts to incorporate the powder.
10. The method of manufacturing a stent set forth in Claim 1, wherein said powder is selected from the group including gold, platinum, tantalum, niobium, titanium or tungsten or
L 5 a combination thereof.
11. A stent manufactured by applying a powder of a material having a higher radiopacity than that of the material from which the stent is formed to a region of the surface of the stent and applying laser light to the surface having the radiopaque powder placed thereon so
10 that the powder is incorporated into the surface of the stent, the stent comprising: a body portion having an outer surface with a powder having a higher radiopacity than that of the material from which the stent is formed incorporated into at least a portion of the surface of the stent.
15 12. The stent set forth in Claim 11, wherein said powder is selected from the group including gold, platinum, tantalum, niobium, titanium or tungsten or a combination thereof.
PCT/GB2002/005076 2001-11-09 2002-11-11 Method for manufacturing a stent WO2003039407A2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2002339126A AU2002339126A1 (en) 2001-11-09 2002-11-11 Method for manufacturing a stent

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB0127033.9A GB0127033D0 (en) 2001-11-09 2001-11-09 Stent manufacture
GB0127033.9 2001-11-09

Publications (2)

Publication Number Publication Date
WO2003039407A2 true WO2003039407A2 (en) 2003-05-15
WO2003039407A3 WO2003039407A3 (en) 2003-11-27

Family

ID=9925543

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB2002/005076 WO2003039407A2 (en) 2001-11-09 2002-11-11 Method for manufacturing a stent

Country Status (3)

Country Link
AU (1) AU2002339126A1 (en)
GB (1) GB0127033D0 (en)
WO (1) WO2003039407A2 (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10335192A1 (en) * 2003-07-30 2005-03-03 Phytis Medical Devices Gmbh Medical implant for animal or human patient made of material allowing use of implant as visualization marker e.g. X-ray marker
WO2005058537A2 (en) * 2003-12-10 2005-06-30 Boston Scientific Limited Medical devices and methods of making the same
EP1674596A1 (en) * 2004-12-21 2006-06-28 United Technologies Corporation Laser enhancements of cold sprayed deposits
WO2006082170A1 (en) * 2005-02-02 2006-08-10 Siemens Aktiengesellschaft Cold gas spraying method
WO2009059141A2 (en) * 2007-11-02 2009-05-07 Boston Scientific Limited Stent with embedded material
WO2009059180A2 (en) * 2007-11-02 2009-05-07 Boston Scientific Limited Stent
US7739781B2 (en) 1996-12-30 2010-06-22 Sorin Biomedica Cardio S.R.L Process for producing a stent for angioplasty
WO2011083321A1 (en) * 2010-01-11 2011-07-14 Smith & Nephew Plc Medical device and method
US8221822B2 (en) * 2007-07-31 2012-07-17 Boston Scientific Scimed, Inc. Medical device coating by laser cladding

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2187988B1 (en) 2007-07-19 2013-08-21 Boston Scientific Limited Endoprosthesis having a non-fouling surface
WO2009020520A1 (en) 2007-08-03 2009-02-12 Boston Scientific Scimed, Inc. Coating for medical device having increased surface area
WO2009131911A2 (en) 2008-04-22 2009-10-29 Boston Scientific Scimed, Inc. Medical devices having a coating of inorganic material
WO2009132176A2 (en) 2008-04-24 2009-10-29 Boston Scientific Scimed, Inc. Medical devices having inorganic particle layers

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2551770A1 (en) * 1983-09-14 1985-03-15 Honda Motor Co Ltd METHOD FOR SURFACE TREATMENT OF A REFLECTIVE METAL PIECE AND PRODUCTS OBTAINED
EP0824900A2 (en) * 1996-08-22 1998-02-25 Advanced Cardiovascular Systems, Inc. Protective coating for a stent with intermediate radiopaque coating
WO2001049340A1 (en) * 1999-12-30 2001-07-12 Advanced Cardiovascular Systems, Inc. Stent with radiopaque coating consisting of particles in a binder
WO2002026162A2 (en) * 2000-09-26 2002-04-04 Advanced Cardiovascular Systems, Inc. A method of loading a substance onto an implantable device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2551770A1 (en) * 1983-09-14 1985-03-15 Honda Motor Co Ltd METHOD FOR SURFACE TREATMENT OF A REFLECTIVE METAL PIECE AND PRODUCTS OBTAINED
EP0824900A2 (en) * 1996-08-22 1998-02-25 Advanced Cardiovascular Systems, Inc. Protective coating for a stent with intermediate radiopaque coating
WO2001049340A1 (en) * 1999-12-30 2001-07-12 Advanced Cardiovascular Systems, Inc. Stent with radiopaque coating consisting of particles in a binder
WO2002026162A2 (en) * 2000-09-26 2002-04-04 Advanced Cardiovascular Systems, Inc. A method of loading a substance onto an implantable device

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7946019B2 (en) 1996-12-30 2011-05-24 Sorin Biomedica Cardio S.R.L. Process for producing a stent for angioplasty
US7739781B2 (en) 1996-12-30 2010-06-22 Sorin Biomedica Cardio S.R.L Process for producing a stent for angioplasty
DE10335192A1 (en) * 2003-07-30 2005-03-03 Phytis Medical Devices Gmbh Medical implant for animal or human patient made of material allowing use of implant as visualization marker e.g. X-ray marker
WO2005058537A2 (en) * 2003-12-10 2005-06-30 Boston Scientific Limited Medical devices and methods of making the same
WO2005058537A3 (en) * 2003-12-10 2005-11-10 Scimed Life Systems Inc Medical devices and methods of making the same
EP1674596A1 (en) * 2004-12-21 2006-06-28 United Technologies Corporation Laser enhancements of cold sprayed deposits
WO2006082170A1 (en) * 2005-02-02 2006-08-10 Siemens Aktiengesellschaft Cold gas spraying method
KR101254150B1 (en) * 2005-02-02 2013-04-18 지멘스 악티엔게젤샤프트 Cold gas spraying method
US8021715B2 (en) 2005-02-02 2011-09-20 Siemens Aktiengesellschaft Cold gas spraying method
US8221822B2 (en) * 2007-07-31 2012-07-17 Boston Scientific Scimed, Inc. Medical device coating by laser cladding
WO2009059180A2 (en) * 2007-11-02 2009-05-07 Boston Scientific Limited Stent
WO2009059141A3 (en) * 2007-11-02 2010-08-12 Boston Scientific Limited Stent with embedded material
WO2009059180A3 (en) * 2007-11-02 2009-09-24 Boston Scientific Limited Stent
WO2009059141A2 (en) * 2007-11-02 2009-05-07 Boston Scientific Limited Stent with embedded material
WO2011083321A1 (en) * 2010-01-11 2011-07-14 Smith & Nephew Plc Medical device and method

Also Published As

Publication number Publication date
WO2003039407A3 (en) 2003-11-27
GB0127033D0 (en) 2002-01-02
AU2002339126A1 (en) 2003-05-19

Similar Documents

Publication Publication Date Title
US7574799B2 (en) Methods of making medical devices
US9675477B2 (en) Welded stent having a welded soluble core
EP1974701B1 (en) Stents incorporating radiopaque markers
WO2003039407A2 (en) Method for manufacturing a stent
EP1652495B1 (en) Expandable stent having a dissolvable portion
US9114032B1 (en) Method of making a stent
US7674416B2 (en) Hybrid intravascular stent
EP2353554B1 (en) Stent
JP2008539889A (en) Tubular stent and manufacturing method thereof
US20100217376A1 (en) Medical devices
US20030065381A1 (en) Longitudinal focussed force stent
EP2185109B1 (en) Endoprostheses having porous claddings prepared using metal hydrides
US20080071344A1 (en) Medical device with porous surface
EP1389451B1 (en) Stent
EP1472991B1 (en) Bifurcated stent with concentric body portions

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SC SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LU MC NL PT SE SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase in:

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP