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WO2005077016A2 - Endoprothese revetue et imagerie par resonance magnetique associee - Google Patents

Endoprothese revetue et imagerie par resonance magnetique associee Download PDF

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Publication number
WO2005077016A2
WO2005077016A2 PCT/US2005/003905 US2005003905W WO2005077016A2 WO 2005077016 A2 WO2005077016 A2 WO 2005077016A2 US 2005003905 W US2005003905 W US 2005003905W WO 2005077016 A2 WO2005077016 A2 WO 2005077016A2
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WO
WIPO (PCT)
Prior art keywords
recited
stent
coated substrate
component
layer
Prior art date
Legal status (The legal status 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 status listed.)
Ceased
Application number
PCT/US2005/003905
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English (en)
Other versions
WO2005077016A3 (fr
Inventor
Xingwu Wang
Robert W. Gray
Jeffrey L. Helfer
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanoset LLC
Original Assignee
Nanoset LLC
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 Nanoset LLC filed Critical Nanoset LLC
Publication of WO2005077016A2 publication Critical patent/WO2005077016A2/fr
Anticipated expiration legal-status Critical
Publication of WO2005077016A3 publication Critical patent/WO2005077016A3/fr
Ceased legal-status Critical Current

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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
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
    • A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
    • A61L31/08—Materials for coatings
    • A61L31/082—Inorganic materials
    • 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
    • A61L31/14—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
    • A61L31/18—Materials at least partially X-ray or laser opaque
    • 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
    • A61F2310/00—Prostheses classified in A61F2/28 or A61F2/30 - A61F2/44 being constructed from or coated with a particular material
    • A61F2310/00389—The prosthesis being coated or covered with a particular material
    • A61F2310/00574—Coating or prosthesis-covering structure made of carbon, e.g. of pyrocarbon
    • 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
    • A61F2310/00—Prostheses classified in A61F2/28 or A61F2/30 - A61F2/44 being constructed from or coated with a particular material
    • A61F2310/00389—The prosthesis being coated or covered with a particular material
    • A61F2310/00592—Coating or prosthesis-covering structure made of ceramics or of ceramic-like compounds

Definitions

  • This invention relates, in one embodiment, to a prosthesis adapted to be visualized under magnetic resonance imaging (MRI) conditions and more particularly to a stent adapted to permit visualization of plaque under MRI conditions.
  • MRI magnetic resonance imaging
  • Medical stents are widely used to treat obstructed lumens, such as blood vessels. Stents are surgically implanted within the lumen of a biological organism. Over time, the undesired reocclusion of the lumen occurs as plaque forms on the surface of the stent; a process referred to as restenosis.
  • a stent is adapted to be implanted in a duct of a human body to maintain an open lumen at the implant site, and to allow viewing body tissue and fluids by magnetic resonance imaging (MRI) energy applied external to the body.
  • the stent constitutes a metal scaffold.
  • An electrical circuit resonant at the resonance frequency of the MRI energy is fabricated integral with the scaffold structure of the stent to promote viewing body properties within the lumen of the stent.”
  • a drawback of stenting is the body's natural defensive reaction to the implant of a foreign object.
  • the reaction is characterized by a traumatic proliferation of tissue as intimal hyperplasia at the implant site, and, where the stent is implanted in a blood vessel such as a coronary artery, formation of thrombi which becomes attached to the stent.
  • a blood vessel such as a coronary artery
  • thrombi which becomes attached to the stent.
  • Each of these adverse effects contributes to restenosis - a re-narrowing of the vessel lumen - to compromise the improvements that resulted from the initial reopening of the lumen by implanting the stent. Consequently, a great number of stent implant patients must undergo another angiogram, on average about six months after the original implant procedure, to determine the status of the tissue proliferation and thrombosis in the affected lumen.
  • United States patent 6,280,385 to Melzer (Stent and MR Imaging Process for the Imaging and the Determination of the Position of a Stent) teaches a stent that has "... at least one passive resonance circuit with an inductance and a capacitance whereby its resonance frequency is essentially equal to the resonance frequency of the applied high-frequency radiation of the magnetic resonance system.”
  • the stent has improved visibility relative to prior art stents.
  • United States patent 6,606,513 to Lardo Magnetic Resonance Imaging Transseptal Needle Antenna discloses "...an MRI transseptal needle that can be visible on an MRI, can act as an antenna and receive MRI signals from surrounding subject matter to generate high-resolution images and can enable real-time active needle tracking during MRI guided transseptal puncture procedures.”
  • United States patents 6,799,067 and 6,845,259 to Pacetti disclose "...a guide wire or other guiding member for use within a patient's body that is at least in part visible under magnetic resonance imaging (MRI) but is not detrimentally affected by the imaging.” Reference may also be had to United States patent 6,712,844 to Pacetti (MRI Compatible Stent); 6,585,755 to Jackson (Polymeric Stent Suitable for Imaging by MRI and Fluoroscopy); and 6,574,497 to Pacetti (MRI Medical 1 Device Markers Utilizing Fluorine-19). United States patent 6,786,904 to Doscher (Method and Device to Treat).
  • Vulnerable Plaque discloses a stent-like-structure that is adapted to remove plaque by heat ablation.
  • MRI Stent United States patent 6,802,857 to Walsh (MRI Stent) teaches a "...stent device [that] includes an electrically conductive helical structure.
  • the stent device also includes an electrically conductive ring structure connected to the helical structure.
  • the ring structure includes an inner conducting ring, an outer conducting ring, and a dielectric material disposed between the inner and outer conducting rings.
  • United States patent 6,831 ,644 to Lienard discloses means for obtaining magnified images of a stent "...images of which are acquired by means of a radiography machine of the type comprising an X-ray source and an image detector and an image display placed opposite the source.”
  • United States patent application 2004/0225326 to Weiner Apparatus for the Detection of Restenosis teaches a stent adapted to detect plaque within the lumen of the stent using electromagnetic radiation.
  • Other attempts to detect or treat restenosis include United States patents 6,015,387; 6,170,488; 6,200,307; 6,488,704; 6,491 ,666 and 6,656,162.
  • a coated stent adapted to be more easily visualized under MR imaging conditions.
  • the techniques and materials described in this specification are advantageous because they are more simple compared to other prior art approaches and may be adapted to function with a variety of stents.
  • Figure 1 is a perspective view of a stent disposed within a lumen ;
  • Figures 2A, 2B and 2C are end views of three stents;
  • Figure 3 is a schematic diagram of a certain circuit
  • Figure 4 is a phase diagram of one composition of the invention.
  • Figures 5A, 5B and 6 are perspective views of coated substrates of the present invention.
  • FIG. 7 is a flow diagram of one process of the present invention.
  • FIG. 8 is an illustration of two out of phase waves used in the present invention.
  • Figure 9 is a photograph of various stents under magnetic resonance imaging conditions both before and after digital post-processing.
  • stents when coated with certain particles, allow for easier visualization of objects contained within the lumens of the stents (for example, plaque due to restenosis).
  • Magnetic resonance imaging can be used to visualize features within a biological organism if there is no magnetic resonance distortion.
  • Many prior art stents give rise to such a distortion, and thus interfere with MR imaging of stents.
  • Figure 1 depicts apparatus 10 wherein stent 14 is disposed within lumen 12.
  • lumen 12 is a blood vessel.
  • lumen 12 may be an artery or vein.
  • other lumens may be used, such as genitourinary lumens and the like.
  • stent 12 is comprised of nitinol. Reference may be had to United States patent 5,147,370 to McNamara (Nitinol Stent for Hollow Body Conduits).
  • stent 12 is comprised of copper. Reference may be had to United States patent 4,969,458 to Wiktor (Intracoronary stent and method of simultaneous angioplasty and stent implant).
  • Figure 2A is an end view of stent 14 under MR imaging conditions. As can be seen in Figure 2A, image artifact 26 obscures any plaque that may be present in stent 14.
  • Figure 2B is an end view of coated stent 24. Disposed about stent 24 is a layer 28 of particles 29. These particles are adapted to at least partially correct the image artifact so that plaque 20 can be visualized within lumen 22 under MRI conditions. In the embodiment depicted in Figure 2B, plaque 20 is present. In the embodiment depicted in Figure 2C, no plaque was detected. Applicants believe that the layer of particles alters the electronic properties of the stent and allows for visualization of the plaque.
  • Figure 3 is a symbolic representation of a circuit diagram that illustrates one theory regarding the operation of the present invention. Without wishing to be bound to any particular theory, applicants believe the stent in the MR scanner functions as an electrical circuit. Figure 3 is an approximation and simplification to the equivalent circuit for the stent plus coatings.
  • the electrical properties of the coated stents are tunable.
  • the coating provides an additional inductance ("L-coating”) to the stent.
  • the dielectric properties of the coatings provide an additional capacitance (“C-coating”) to the stent. This allows the stent-coating-tissue system's "circuit" parameters to be adjusted by varying the composition of the coating.
  • phase characteristics of the MR signal emitting from the tissue may be controllably adjusted and discriminated in the phase data; (2) nullification of field inhomogeneities due to the MR-induced magnetization of stent materials; (3) reduction of MR-induced eddy and loop currents by changing the surface resistance and the impedance characteristics of the stents, and (4) enhanced edge discrimination compared to uncoated stents.
  • the nullification of field inhomogeneities may be accomplished by altering the composition of the particles (such as iron content) and layer properties (such as thickness). This coating adjustment is interrelated to other stent/coating properties.
  • stents may be made from a variety of materials, including copper and nitinol.
  • Copper has a magnetic susceptibility less than zero while nitinol has a magnetic susceptibility greater than zero. Therefore, the present coatings need to be adjusted differently depending on the substrate that the coatings are applied to.
  • the inductance of the system is related to magnetic susceptibility.
  • the capacitance is related to the dielectric properties. In the case of a nitinol stent, adjustment of the coating capacitance in this oscillating system combined with the inductance properties helps to reduce some of the magnetic susceptibility effects of the substrate.
  • the particles of the present invention are comprised of three moieties, denoted A, B, and C.
  • the particles of this invention are comprised of aluminum, iron, and nitrogen atoms.
  • the particles are comprised of aluminum, iron, and a mixture of nitrogen and oxygen atoms.
  • Figure 4 illustrates a phase diagram comprised of moieties A, B, and C.
  • A is a magnetic moiety.
  • moiety A is selected from the group consisting of iron, nickel, samarium, and gadolinium.
  • moiety A is selected from the group consisting of iron and nickel.
  • moiety A is iron.
  • the moiety B have a resistivity of from about 2 to about 100 microohm-centimeters.
  • moiety B is selected from the group consisting of aluminum, copper, gold, silver, and mixtures thereof.
  • B is aluminum with a resistivity of about 2.824 microohm-centimeters.
  • other materials with resistivities within the desired range also may be used.
  • B is selected from the group consisting of aluminum, silicon, copper, and combinations thereof.
  • B is selected from the group consisting of aluminum, silicon and copper.
  • B is selected from the group consisting of aluminum and copper.
  • B is aluminum.
  • C is selected from the group consisting of nitrogen, oxygen, carbon and combinations thereof. In another embodiment, C is selected from the group consisting of nitrogen, oxygen, and combinations thereof. In yet another embodiment C is a mixture of oxygen and nitrogen.
  • the particles found in these coatings have very small magnetic domains (in one embodiment from about 3 to about 10 nanometers) as opposed to the very large "bulk" magnetic domains in other, prior art magnetic materials. This causes the magnetic moments of the coatings to respond to external field changes. Additionally, the particles may be dispersed within a matrix.
  • the resulting coating may allow more magnetic flux lines to pass through the coating and into the stent's interior than traditional bulk magnetic materials would.
  • this matrix is comprised of aluminum and nitrogen.
  • the size of the magnetic domains can be related to the coherence length between the particles.
  • the coherence length between adjacent A moieties is, on average, preferably from about 0.1 to about 100 nanometers and, more preferably, from about 1 to about 50 nanometers. In one embodiment, the coherence length is from about 3 to about 20 nanometers.
  • the average particle size of the particulates is less than 100 nanometers. In another embodiment, the average particle size of the particulates is less than about 50 nanometers. In another embodiment, the average particle size of the particulates is from about 2 nanometers to about 50 nanometers. In another embodiment, the average particle size of the particulates is from about 2 nanometers to about 10 nanometers.
  • the particulate material is coated onto a stent to form a layer so as to provide a saturation magnetization, at 25 degrees centigrade, of a certain value.
  • this layer has a saturation magnetization of at least about 2,000 gauss.
  • the layer of particulate material has a saturation magnetization of at least about 5,000 gauss.
  • the layer of particulate material has a saturation magnetization of at least about 10,000 gauss.
  • the layer of particulate material has a saturation magnetization of at least about 20,000 gauss.
  • the layer of particulate material has a saturation magnetization of at least about 26,000 gauss.
  • the aforementioned layer of particulate material may be coated onto the stent in various thicknesses.
  • the thickness of the layer is less than about 100 microns. In one embodiment, the thickness of the layer is less than about 10 microns. In another embodiment, the thickness of the layer is less than about 5 microns. In another embodiment, the thickness of the layer is from about 0.1 to about 3 microns.
  • the thickness of the layer of particulate material is measured from the bottom surface of the layer that contains such material to the top surface of such layer that contains such material; and such bottom surface and/or such top surface may be contiguous with other layers of material (such as insulating material) that do not contain these particles. In one embodiment, these other layers consist essentially of aluminum and nitrogen.
  • coated stents of this invention may be prepared by other conventional means such as, e.g., the process described in United States patent 5,540,959 to Wang (Process for Preparing a Coated Substrate).
  • This patent describes and claims a process for preparing a coated substrate, comprising the steps of: (a) creating mist particles from a liquid, wherein: 1. said liquid is selected from the group consisting of a solution, a slurry, and mixtures thereof, 2.
  • said liquid is comprised of solvent and from 0.1 to 75 grams of solid material per liter of solvent, 3. at least 95 volume percent of said mist particles have a maximum dimension less than 100 microns, and 4. said mist particles are created from said first liquid at a rate of from 0.1 to 30 milliliters of liquid per minute; (b) contacting said mist particles with a carrier gas at a pressure of from 761 to 810 millimeters of mercury; (c) thereafter contacting said mist particles with alternating current radio frequency energy with a frequency of at least 1 megahertz and a power of at least 3 kilowatts while heating said mist particles to a temperature of at least about 100 degrees centigrade, thereby producing a heated vapor; (d) depositing said heated vapor onto a substrate, thereby producing a coated substrate; and (e) subjecting said coated substrate to a temperature of from about 450 to about 1 ,400 degrees centigrade for at least about 10 minutes.
  • coatings of certain particles can be applied to the stent so as to alter some of the stent's electrical parameters. These parameters include the stent's surface resistance and its overall inductance. Additionally, the coatings provide a dielectric layer between the conductor of the stent and the body tissue and fluids. This enables multilayer coatings to form a capacitance per unit length of the stent. In one embodiment, one of these layers is a matrix that consists essentially of aluminum and nitrogen.
  • Figure 5A depicts a single layered coating assembly 51.
  • stent 24 is coated with layer 28 with a thickness 52.
  • the particles (not shown) of the present invention are disposed within layer 28.
  • the stents are often coating on all sides. For the sake of clarity, only one side is shown as coated.
  • Figure 5B illustrates a multilayered coating assembly 53.
  • stent 24 is coated with layer 54 which had a thickness 56.
  • layer 54 consists essentially of aluminum and nitrogen. Disposed above layer 54, and congruent therewith, is layer 28. The particles (not shown) of the present invention are disposed within layer 28.
  • FIG 6 is an illustration of another multilayered coating assembly 60.
  • stent 24 is coated with layer 54 which has a thickness 56.
  • layer 54 consists essentially of aluminum and nitrogen. Disposed above layer 54, and contiguous therewith, is layer 28 which has a thickness 52. Disposed within layer 28 are the particles (not shown) of the invention.
  • layer 55 Disposed above layer 28 is layer 55.
  • layer 55 is comprised of substantially the same material as layer 54.
  • layers 28, 54 and 55 have approximately the same thickness. In other embodiments
  • the thicknesses may vary.
  • FIG. 7 is a flow diagram of one process 77 of the invention.
  • a coated stent is imaged by MRI.
  • a stent is coated with particles in accordance with the teachings of this specification.
  • the coated stent is disposed with a biological organism. In one embodiment, the biological organism is a human being.
  • the coated stent is placed within a MR imaging scanner.
  • the stent is exposed to electromagnetic radiation (for example, radio frequency waves) from the MR imaging scanner.
  • electromagnetic radiation for example, radio frequency waves
  • a digital image of the stent is produced by the MR imaging scanner.
  • the resulting digital image is observed by the end user. In this manner, the end user can visualize the interior of the stent and examine it for plaque formation.
  • the digital image is enhanced with post-processing software prior to being observed.
  • suitable post-processing techniques are known to those skilled in the art. It is well established that digital image provided by MR imaging may be separated into magnitude data and phase data. Digital imaging software may be used to enhance the magnitude and phase data.
  • Figure 8 is an illustration of two electromagnetic waves; wave 80 and wave 83.
  • Waves 80 and 83 have magnitudes 81 and 82 respectively. Waves 80 and 83 are out of phase in time by phase difference 84.
  • Prior art digital image process methods teach the use of magnitude and phase data to perform enhancements of digital images. Reference may be had to United States patents 6,674,904 to McQueen (Contour Tracing and Boundary Detection for Object Identification in a Digital Image); 6,215,983 to Dogan (Method and Apparatus for Comlex Phase Equalization for use in a Communication System); 6,370,224 to Simon (System and Methods for the Reduction and Elimination of Image Artifacts in the Calibration of X-Ray Imagers); 6,011 ,862 Doi (Computer-Aided Method for Automated Image Feature Analysis and Diagnosis of Digitized Medical Images); 6,007,052 to Tinkler (System and Method for Local Area Image Processing); 6,005,983 to Anderson (Image Enhancement by Non-Linear Extrapolation in Freque
  • Figure 9 is a photograph 90 of six copper rings under MR imaging conditions.
  • a nylon rod was disposed within the rings to simulate an object within a stent.
  • the first row is the MR image wherein the image was constructed using the magnitude data from the MR scanner.
  • the second and thirds rows are the same image after post-processing enhancements have been applied. In the second row magnitude equalization was used to enhance the image. In the third row the magnitude data was used to perform an edge detection algorithm.
  • the fourth row is the MR image wherein the image was constructed using the phase data from the MR scanner.
  • the fifth and sixth rows are the same image after post-processing enhancements have been applied. In the fifth row, phase equalization was used to enhance the image. In the sixth row the phase data was used to perform an edge detection algorithm.
  • Ring 95 has been cut so that it functions as an idealized reference. Since ring 95 is cut, it has no eddy currents. Thus, the nylon rod within ring 95 is clearly visible under MRI conditions. For example, when an edge detection algorithm is run on the phase data (row six) the nylon rod is quite apparent. Rings 91 , 92, and 93 are uncoated copper rings which serve as a reference. It is clear from Figure 9 that the nylon rod within rings 91 , 92 and 93 are much more difficult to detect. In contrast, ring 94 is coated in accordance with the teachings of this invention.
  • the nylon object within ring 94 is visible under MR imaging conditions.
  • the appearance of the nylon object within ring 94 is markedly superior to the non-coated rings 91 to 93. This is especially true after the image has been subjected to a phase edge detection algorithm.
  • the phase edge detection of ring 94 is substantially to the idealized cut ring 95.

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  • Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Animal Behavior & Ethology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • General Health & Medical Sciences (AREA)
  • Vascular Medicine (AREA)
  • Veterinary Medicine (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Epidemiology (AREA)
  • Surgery (AREA)
  • Biomedical Technology (AREA)
  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • Cardiology (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Transplantation (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
  • Materials For Medical Uses (AREA)

Abstract

L'invention porte sur une endoprothèse revêtue d'une couche constituée de particules qui présentent une granulométrie inférieure à 100 manomètres ; une magnétisation à saturation d'au moins 2,000 gauss; le longueur de cohérence moyenne entre les particules étant comprise entre environ 1 et 50 nanomètres.
PCT/US2005/003905 2004-02-05 2005-02-07 Endoprothese revetue et imagerie par resonance magnetique associee Ceased WO2005077016A2 (fr)

Applications Claiming Priority (2)

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US54227004P 2004-02-05 2004-02-05
US60/542,270 2004-02-05

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WO2005077016A3 WO2005077016A3 (fr) 2007-12-13

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JP4149648B2 (ja) * 2000-09-29 2008-09-10 富士フイルム株式会社 磁気記録媒体
US6818138B2 (en) * 2001-06-22 2004-11-16 Hewlett-Packard Development Company, L.P. Slotted substrate and slotting process

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