Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS20030111142 A1
Publication typeApplication
Application numberUS 10/256,751
Publication dateJun 19, 2003
Filing dateSep 27, 2002
Priority dateMar 5, 2001
Also published asUS20020162605
Publication number10256751, 256751, US 2003/0111142 A1, US 2003/111142 A1, US 20030111142 A1, US 20030111142A1, US 2003111142 A1, US 2003111142A1, US-A1-20030111142, US-A1-2003111142, US2003/0111142A1, US2003/111142A1, US20030111142 A1, US20030111142A1, US2003111142 A1, US2003111142A1
InventorsJoseph Horton, Douglas Parsell
Original AssigneeHorton Joseph A., Parsell Douglas E.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Bulk metallic glass medical instruments, implants, and methods of using same
US 20030111142 A1
Abstract
MRI-compatible medical instruments and appliances are made using bulk metallic glass alloys. MRI-guided methods include the use of articles that include bulk metallic glass alloys.
Images(4)
Previous page
Next page
Claims(7)
What is claimed is:
1. A method of carrying out a medical procedure comprising the steps of:
a. providing an article selected from the group consisting of medical instruments and biomedical appliances, at least a portion of said article comprising a bulk metallic glass; and
b. using said article to carry out a medical procedure wherein an MRI image of at least part of said article is made.
2. A method in accordance with claim 1 wherein said medical procedure is an orthopedic procedure.
3. A method in accordance with claim 1 wherein said medical procedure is an endodontic procedure.
4. A method in accordance with claim 1 wherein said medical procedure comprises an MRI-guided procedure.
5. A method of carrying out an MRI-guided procedure comprising the steps of:
a. providing an article, at least a portion of said article comprising a bulk metallic glass; and
b. using said article to carry out an MRI-guided procedure.
6. A method in accordance with claim 5 wherein said MRI-guided procedure further comprises a medical procedure.
7. A method in accordance with claim 5 wherein said MRI-guided procedure further comprises a non-medical procedure.
Description
    CROSS-REFERENCE TO RELATED APPLICATIONS
  • [0001]
    This application is a divisional application of U.S. patent application Ser. No. 09/799,445, filed on Mar. 5, 2001, the entirety of which is incorporated herein by reference.
  • [0002] This invention was made with Government support under Contract No. DE-AC05-00OR22725 awarded by the United States Department of Energy. The Government has certain rights in the invention.
  • FIELD OF THE INVENTION
  • [0003]
    The present invention relates to medical, surgical, and dental hardware, especially medical instruments and biomedical appliances, and particularly to those instruments and appliances at least partially constructed of a bulk metallic glass (BMG), and to methods of using the same.
  • BACKGROUND OF THE INVENTION
  • [0004]
    The concept of magnetic susceptibility is central to many current research and development activities in magnetic resonance imaging (MRI). For example, the development of MR-guided surgery has created a need for surgical instruments and other devices with susceptibility tailored to the MR environment; susceptibility effects can lead to position errors of up to several millimeters in MR-guided stereotactic surgery; and the variation of magnetic susceptibility on a microscopic scale within tissues contributes to MR contrast and is the basis of functional MRI. The magnetic aspects of MR compatibility are discussed in terms of two levels of acceptability: Materials with the first kind of magnetic field compatibility are such that magnetic forces and torques do not interfere significantly when the materials are used within the magnetic field of the scanner; materials with the second kind of magnetic field compatibility meet the more demanding requirement that they produce only negligible artifacts within the MR image and their effect on the positional accuracy of features within the image is negligible or can readily be corrected. Several materials exhibiting magnetic field compatibility of the second kind have been studied and a group of materials that produce essentially no image distortion, even when located directly within the imaging field of view, is identified. Because of demagnetizing effects, the shape and orientation, as well as the susceptibility, of articles within and adjacent to the imaging region is important in MRI, but the use of literature values for the susceptibility of materials is often difficult because of inconsistent traditions in the definitions and units used for magnetic parameters—particularly susceptibility.
  • [0005]
    Thus, methods and apparatus have long been sought to permit surgical procedures involving surgical instruments and/or surgically implanted appliances to be guided or monitored by MRI.
  • [0006]
    For this to be possible, a new implant material has long been needed which has a low MRI signature. In addition, it would be desirable for such materials to also have high hardness, tensile strength, and toughness. A desirable material would have a lower elastic modulus and an extremely high elastic limit of about 2% compared to that of a typical metal, namely about 0.2%. Bone has an elastic limit of about 1%. Such material would be unique in its ability to flex elastically with the natural bending of the bones and so distribute stresses more uniformly. Faster healing rates would result from reduced stress shielding effects while minimizing stress concentrators. Because of these unique mechanical properties, screws could have a thinner shank and deeper threads yielding greater holding power. Applications where such material is desirable would include such as fracture fixation screws, rods, pins, knee and hip joint wear surfaces and shafts, and aneurysm clips. A large variety of other applications, changes and modifications would be obvious to those skilled in the art.
  • [0007]
    Current implant materials produce a distortion or blooming (enlargement) in the MRI image. Larger implants are even internally heated during an MRI. This is especially important for aneurysm clips where later imaging is often needed and where no movement of the clip as a result of an MRI is essential.
  • [0008]
    Definitions:
  • [0009]
    A bulk metallic glass (BMG) is defined for purposes herein as an amorphous metallic alloy that is cast in bulk form. A BMG is known to be inclusive of amorphous thin-film materials such as those that are typically deposited on surfaces.
  • [0010]
    A medical instrument is defined for purposes herein as any device used by medical and/or dental personnel in any surgical and/or dental procedure.
  • [0011]
    A biomedical appliance is defined for purposes herein as any medically functional device that is configured for disposition on or inside a living body, including surgically implanted orthopedic devices, dental implants, and the like.
  • OBJECTS OF THE INVENTION
  • [0012]
    Accordingly, objects of the present invention include at least the following:
  • [0013]
    provision of new and improved medical instruments and biomedical appliances having at least one of: desirably high elastic limit, hardness, strength, toughness, and ability to hold a cutting edge;
  • [0014]
    provision of new and improved MRI-compatible medical instruments and surgically implantable orthopedic appliances that allow surgeries to be guided in real time by MRI imaging;
  • [0015]
    provision of new and improved surgically implantable appliances (e.g., orthopedic, endodontic, etc.) with mechanical properties compatible with those of bone, low corrosion rate, and good biocompatibility (lack of rejection by human or animal tissue);
  • [0016]
    provision of new and improved articles configured for use as tools, instruments, and parts used for maintaining, inspecting, modifying, operating, or exploring both man-made and naturally-occurring structures which are internally or externally viewable by MRI; and
  • [0017]
    provision of new and improved methods of performing medical and dental procedures utilizing the aforementioned instruments and appliances.
  • [0018]
    Further and other objects of the present invention will become apparent from the description contained herein.
  • SUMMARY OF THE INVENTION
  • [0019]
    In accordance with one aspect of the present invention, the foregoing and other objects are achieved by an article, at least a portion of which includes a bulk metallic glass having magnetic properties suitable for producing an MRI image, the article having a shape suitable for producing an MRI image and being configured for use as a medical instrument and/or a biomedical appliance.
  • [0020]
    In accordance with another aspect of the present invention, a method of carrying out a medical procedure includes the steps of: providing a medical instrument or a biomedical appliance, at least a portion of which includes a bulk metallic glass; and using the medical instrument or biomedical appliance to carry out a medical procedure.
  • [0021]
    In accordance with a further aspect of the present invention, a method of carrying out an MRI-guided procedure includes the steps of: providing an article, at least a portion of which includes a bulk metallic glass; and using the article to carry out an MRI-guided procedure.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0022]
    In the drawings:
  • [0023]
    [0023]FIG. 1 is a full-scale MRI image of a 7 mm diameter rod of a conventional copper alloy (Cu-4 Cri-2 Nb) in salt water.
  • [0024]
    [0024]FIG. 2 is a full-scale MRI image of a 7 mm diameter rod of BAM-11 in salt water in accordance with the present invention.
  • [0025]
    [0025]FIG. 3 is a full-scale MRI image of a 7 mm diameter rod of Ni-free BMG in salt water in accordance with the present invention.
  • [0026]
    [0026]FIG. 4 is a full-scale MRI image of a bullet nosed 6 mm diameter rod of Ti-6 Al-4.
  • [0027]
    [0027]FIG. 5 is a full-scale MRI image of a bullet nosed 6 mm diameter rod of BAM-11 in salt water in accordance with the present invention.
  • [0028]
    [0028]FIG. 6 is a view of a typical conventional orthopedic bone screw.
  • [0029]
    [0029]FIG. 7 is a view of an orthopedic bone screw of an improved design made possible by the use of BMG in accordance with the present invention.
  • [0030]
    For a better understanding of the present invention, together with other and further articles, advantages and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the above-described drawings.
  • DETAILED DESCRIPTION OF THE INVENTION
  • [0031]
    It has been discovered that certain bulk metallic glass (BMG) alloys have a very low MRI signature. BMG materials have high hardness, tensile strength, and toughness. The present invention is based on the discovery that the unique properties of BMG alloys make them especially suitable for biomedical implant applications as well as for medical instruments.
  • [0032]
    The invention described and claimed herein involves both apparatus and methods for the use of medical instruments and surgically implantable devices made of bulk metallic glasses during surgical and dental procedures in an intervention MRI in which the MRI guides the surgery in real time. The bulk metallic glass has an excellent MRI signature due to its amorphous structure. An accurate signature of the metallic implant or instrument is of paramount importance for accurate position information of the instrument or implant device.
  • [0033]
    It is recognized that a large range of specific compositions of BMG are known to and may be used by the skilled artisan in this invention. . For example, see U.S. Pat. No. 5,735,975 issued on Apr. 7, 1998 to Lin, et al. entitled “Quinary Metallic Glass Alloys” and U.S. Pat. No. 5,803,996 issued on Sep. 8, 1998 to Inoue, et al. entitled “Rod-Shaped or Tubular Amorphous Zr Alloy Made by Die Casting and Method for Manufacturing said Amorphous Zr Alloy”. The patents of both Lin and Inoue are incorporated herein by reference. The specific composition of the alloy used in examples described herein is Zr -17.9 Cu -14.6 Ni -5 Ti -10 Al (at %).
  • [0034]
    It is further recognized that attempts have been made in the past to provide medical instruments which cause reduced or enhanced artifact on diagnostic images such as MRI images. One such example is U.S. Pat. No. 5,895,401, issued Apr. 20, 1999, “Controlled-Artifact Magnetic Resonance Instruments” by Daum et al. However, Daum teaches a crystalline alloy comprising at least 85% titanium and does not teach an alloy which is amorphous such as the bulk metallic glass taught herein. Conversely, the bulk metallic glass as taught herein contains no more than 12 at. % titanium. Thus the present invention and Daum teach grossly different materials.
  • [0035]
    Because of the unique atomic structure in an amorphous metallic glass, this material possesses unique magnetic properties that allow the excellent MRI signature.
  • [0036]
    The composition tested contains substantial amounts of a ferromagnetic element, Ni. In a crystalline structure, the presence of Ni produces substantial blooming in an MRI image. All of the other elements in this alloy, namely Zr, Ni, Ti, and Al all have susceptibilities substantially higher than that of human tissues thereby producing a positional error in the MRI image. Only copper has susceptibility similar to human or animal tissues. Comparison images show that the image of the BMG is better even than a copper alloy. All bulk metallic glasses that are not expressly designed for good soft or hard ferromagnetic properties are expected to have this good MRI signature.
  • [0037]
    BMG alloys have a lower modulus and an extremely high elastic limit of about 2% as compared to that of a typical metal, namely about 0.2%. Bone has an elastic limit of about 1%. BMGs are unique in their ability to flex elastically with the natural bending of bones and so distribute stresses more uniformly. Faster healing rates result from reduced stress shielding effects while minimizing stress concentrators. Because of the unique mechanical properties of the BMGs, screws can have a thinner shank and deeper threads yielding greater holding power. Compared to the lowest modulus developmental titanium alloy, for a given load, the BMG will require 1/4 the cross section to carry the load and will undergo twice the deflection. Compared to stainless steel, the area will be 1/3 to carry the load and the BMG will have 5 times the deflection. Potential applications include fracture fixation screws, rods, pins, hip joint wear surfaces and shafts, aneurysm clips, endodontic files and orthodontic arch wires as well as components of devices such as pacemakers, neurostimulators, medicine-metering pumps, and equipment for remotely-viewed microsurgery.
  • [0038]
    [0038]FIGS. 1 and 2 show comparison MRI images of a copper alloy and a BMG alloy (Zr -17.9 Cu -14.6 Ni -5.0 Ti -10.0 Al, referred to here as BAM-11 (all compositions are in atomic %) in a flask of salt water showing much less bloom with the BMG alloy. This is a surprising result, since one would expect the susceptibility to be close to that of zirconium as the major constituent and the nickel in the alloy should make it higher. While copper is the metal with a susceptibility closest to that of living human or animal tissue, it is too soft for many uses, especially medical instruments and implants. The toxicity of beryllium all but prohibits the use of the harder Be—Cu alloys. For these reasons, the unique magnetic properties of BMG materials yield the ability to fabricate MRI-friendly implant devices as well as a new class of medical instruments for use within the interventional MRI environment. Minimally invasive procedures not possible via conventional surgical and dental techniques can be successfully performed through interventional MRI, indicating a critical need for instruments to facilitate these procedures.
  • [0039]
    Prior to the recent development of these bulk metallic glasses, rapid solidification such as melt spinning or gas atomization producing thin ribbons or powders (<150 mm) was required to achieve the sufficiently high cooling rates necessary for glass formation. Due to their unique amorphous microstructure with a number of different elements present, the BMGs exhibit a number of exceptional properties. For example, alloy BAM-11 has a yield strength of 1900 MPa, an elastic limit of 2 to 2.2%, Young's Modulus of 90 GPa, Vickers hardness of 590 kg/mm2, and a toughness of 55 to 60 MPa{square root}M. Table 1 lists mechanical properties of BMGs and compares them to that of the three most commonly used implant materials and to one of the new low-modulus titanium alloys under development. Table 2 lists some potential applications for BMG alloys.
  • [0040]
    (Table 1 begins next page)
    TABLE 1
    Mechanical properties of bulk metallic glass compared to
    the three leading implant materials
    Experimen-
    tal Ti-
    BMG Ti-6Al- 35Nb-5
    Property (BAM 11) Co-Cr 4V 316L-CW Bone Ta-7 Zr
    Tensile Yield 1900 450 830 690 Compressive 547
    Strength, MPa 130-150
    (cortical)
    Elastic Strain   2-2.2 0.18 0.67 0.34 1% 0.9
    Limit, %
    Plastic Strain 1 8 10 12 19
    to failure, %
    Young's Modulus, 90 248 124 200 17* 55
    GPa
    Hardness, Vickers, 590 350-390 320 365
    Kg/mm2
    Toughness, Mpa m1/2 55-60 57 100
    Fatigue load for failure 310 520 240 265
    at 107 cycles, MPa
    Density, g/cc 5.9 8.5 4.4 8
    Biocompatibility Good, Good/ Good Good/ good
    initial question- question-
    evaluation able able
    Magnetic Very Probably Ti is Austenitic is Human tissue Probably
    Susceptibility compat- ferro- 182 × 3-6 × is −11 to similar to
    ible magnetic 10−6 10−3 −7 × Ti
    CW is 10−6
    ferro-
    magnetic
  • [0041]
    [0041]
    TABLE 2
    Summary of potential health field application for bulk metallic glasses
    Critical Property
    Application Unique BMG Property Measurement Comments
    Fracture Fixation and Fusion Lower modulus, high Fatigue, crack initiation at Some plates require plastic
    Plates strength drill holes, corrosion, deformation to adjust fit at
    biocompatability time of insertion which
    BMG could not
    accommodate.
    Screws Toughness, high strength Fatigue, corrosion, Less wear debris will lead to
    biocompatability less immune system
    response.
    Hip joints-wear surface Low coefficient of friction, Wear, corrosion, Less wear debris will lead to
    hardness biocompatability less immune system
    response.
    Hip joints-shaft Low modulus Corrosion, biocompatability Lower modulus distributes
    load better
    Cutting tools, scalpel, bone Toughness, high elastic Edge holding, susceptibility May have longer life than
    biopsy osteotome, limit, hardness SS that quickly dull.
    endodontic files
    Aneurysm clips High elastic limit, good MRI Creep, corrosion, Can do emergency MRI
    signature biocompatability later without possible fatal
    results
    Orthodontist Arch Wires High elastic limit, low Processing to preform or Need to slide in mounts
    coefficient of friction cast to proper shape (hard enough to be
    compatible with ceramic
    brackets), maintain force
    over large elastic
    deformations
    MRI interventional surgical Good MRI signature, Edge holding, susceptibility A unique material for the
    instruments toughness, hardness next generation of surgical
    care in an interventional
    MRI
  • EXAMPLE I
  • [0042]
    Initial screening tests on BAM-11 performed at the Biomaterials and Orthopedic Research Department at the University of Mississippi Medical Center have shown biocompatibility comparable to current implant materials. For initial biocompatibility screening, two cell lines were selected: microphage and fibroblast. Because these cell types are key in inflammation and encapsulation processes they are generally predictive of soft tissue biocompatibility. Four analyses of biocompatibility were conducted for each cell type: 1) cellular viability, 2) catalase activity, 3) TNF beta cytokine concentration and 4) lactate dehydrogenase concentration. The results are presented in Table 3.
    TABLE 3
    Initial Biocompatability Tests of BAM-11 compared to two control
    specimens*
    BAM-11 Ti, commercially pure Polyethylene
    Macrophage Viability, 85 90 91
    %
    Macrophage/Catalase 18 22 12
    Activity/standardized
    activity/protein quan-
    tity
    Macrophage/Lactate 6 8 6
    Dehydrogenase, stan-
    dardized activity/pro-
    tein quantity
    Macrophage/Cytokine, 19 18 11
    picograms/protein
    quantity
    Fibroblast Viability, % 95 90 92
    survival
    Fibroblasts/Catalase 9 5 5.5
    Activity standardized
    activity/protein
    quantity
    Fibroblast/Lactate 6.5 4 5
    Dehydrogenase, stan-
    dardized activity/
    protein quantity
  • EXAMPLE II
  • [0043]
    Screening tests on BAM-11 specimens performed at the Biomaterials and Orthopedic Research Department at the University of Mississippi Medical Center have shown corrosion resistance comparable to current implant materials. All specimens were wet ground with SiC paper, 80, 240, 320, 600, and 1500 grit followed by ultrasonic cleaning in distilled water for 5 min. The titanium was additionally passivated in 40% HNO3 for 30 min according to an ASTM standard. Cyclic polarization tests were conducted on triplicate samples of the alloys in Ringer's solution (9.0 g/L-NaCl, 0.42 g/L-KCl, 0.25 g/L-CaCl2). Specimens were allowed to reach an open-circuit potential (Ecorr) for a period of one hour. A potential scan increasing at a rate of 0.1667 mV/s (ASTM G5) was then initiated at 100 mV below Ecorr and continued until a current threshold of 1×10-2A/cm2 was reached. At this point the scan was reversed and decreased in the same rate until Ecorr was reached. The results are presented in Table 4.
    TABLE 4
    Initial corrosion tests of BAM-11
    Alloy Ecorr (mV) Rbr (mV) Icorr (na/cm2)
    Titanium  −51 ± 61.5 None recorded 8.2 ± 3.4
    316L SS −72.7 ± 20    323 ± 66.4 14.1 ± 6.7 
    BAM11 −228.3 ± 38.6  −65.3 ± 53.0  56.1 ± 32.8
  • [0044]
    While currently used surgically implantable orthopedic appliances contain nickel, we have developed compositions that eliminate nickel due to long-term biocompatibility concerns.
  • EXAMPLE III
  • [0045]
    Alloys with composition of Zr-32.5 Cu-5 Ti-10 Al (at. %) were arc cast into a water-cooled copper mold and as cast were 99% amorphous. FIG. 3 shows an MRI image of this new alloy compared to a Cu alloy (FIG. 1) and the BAM-11 alloy (FIG. 2). It is evident that without Ni an even better MRI image is obtained. This is attributed to both removal of Nickel and the high percentage of amorphous material.
  • [0046]
    It is believed that removal of the nickel is not necessary for use of the BMGs as instruments and temporary fixation devices such as immobilizing screws. Instruments such as bone biopsy tools, scalpel blades, and the like have been fabricated by well-known, conventional techniques such as casting, machining, laser welding, grinding, and polishing.
  • [0047]
    Magnetic properties of BMGs are also of interest. One of the first commercial uses of rapidly solidified amorphous metals was the Fe—B based alloy for read-write heads and now transformer cores. The BMGs also have been found to have unusual magnetic properties including a soft magnetic alloy with zero magnetostriction, a hard magnetic alloy with only 30% Fe that does not saturate at 15 Tesla and has the highest ever measured coercivity, 8.4T, although at liquid helium temperature. In general, the magnetic susceptibility is related to density of electronic states at the Fermi energy. Knowledge of the composition dependence of the susceptibility would provide important input in refining models of the amorphous state through first principles calculations of the electronic structure and hence the Fermi energy density of states. The preliminary result presented here concerning a good MRI image was surprising considering the composition and especially the presence of nickel in the alloy. Actual direct measurements of the magnetic susceptibility by a squid magnetometer yield 109×10-6 for BAM-11 versus 182×10-6 for Ti-6 Al-4 V agreeing with the MRI results.
  • [0048]
    Mechanical properties of the BMG described herein are superior for many surgically implantable appliances and medical instruments than currently used materials. These properties include higher yield strength, higher elastic strain limit, lower Young's modulus (better for reducing stress shielding), higher hardness, and comparable toughness. For example, Because of these unique mechanical properties, screws could have a thinner shank and deeper threads yielding greater holding power. For example, FIG. 6 shows of a typical conventional orthopedic bone screw design, while FIG. 7 shows an orthopedic bone screw of an improved design made possible by the use of BMG in accordance with the present invention.
  • [0049]
    BMG is uniquely suited for MRI compatible medical instruments and surgically implantable devices because of minimal generation of image distortion. Information readily available from MRI images is critically helpful for many types of surgical procedures. MRI images not only function to guide the surgeon's tools to the location of the procedure along the least damaging path, but also to differentiate and define tissue types for facilitation of more efficient and complete procedures. BMG constructed surgical tools allow for a host of procedures to be performed in the MRI environment. BMG offers the best MRI-compatible cutting instruments available. As such, procedures involving the cutting of bone could be MRI-guided. Examples of such procedures include craniotomy procedures involving tumors, embolisms or strokes and orthopedic procedures involving femoral avascular necrosis and vertebral fusions.
  • [0050]
    A broad range of other non-medical, even non-biological applications is available to the skilled artisan. Remote viewing and control of diagnostic apparatus and apparatus used to maintain or repair any structure which is viewable using MRI technology is enabled by using instruments and implants constructed of BMG, with minimal invasion of the structure, minimal disturbance of the system the structure functions within, and minimal disruption of processes. Applications might include diagnosis, maintenance, and repair of such structures as electronic structures, composite structures used in aerospace, marine, and other endeavors, or remotely disarming of hazardous structures such as bombs, mines, and other explosives.
  • [0051]
    It should be noted that ferromagnetic metallic glasses are not suitable for MRI imaging and are specifically excluded from the scope of the present invention. See, for example, U.S. Pat. No. 5,976,274 issued on Nov. 2, 1999 to Inoue, et al. entitled “Soft Magnetic Amorphous Alloy and High Hardness Amorphous Alloy and High Hardness Tool Using the Same” and U.S. Pat. No. 4,653,500 issued on Mar. 31, 1987 to Osada, et al. entitled “Electrocardiographic amorphous alloy electrode”.
  • [0052]
    While there has been shown and described what are at present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the inventions defined by the appended claims.
Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3940293 *Jan 27, 1975Feb 24, 1976Allied Chemical CorporationMethod of producing amorphous cutting blades
US4116682 *Dec 27, 1976Sep 26, 1978Polk Donald EAmorphous metal alloys and products thereof
US4318738 *Oct 3, 1979Mar 9, 1982Shin-Gijutsu Kaihatsu JigyodanAmorphous carbon alloys and articles manufactured from said alloys
US4557766 *Mar 5, 1984Dec 10, 1985Standard Oil CompanyBulk amorphous metal alloy objects and process for making the same
US4653500 *Dec 17, 1985Mar 31, 1987Fukuda Denshi Co., Ltd.Electrocardiographic amorphous alloy electrode
US4762677 *Nov 3, 1987Aug 9, 1988Allied-Signal Inc.Method of preparing a bulk amorphous metal article
US4762678 *Nov 3, 1987Aug 9, 1988Allied-Signal Inc.Method of preparing a bulk amorphous metal article
US4827931 *Jan 13, 1987May 9, 1989Longmore Donald BSurgical catheters with suturing device and NMR opaque material
US4880482 *Apr 19, 1988Nov 14, 1989Mitsui Engineering & Shipbuilding Co., Ltd.Highly corrosion-resistant amorphous alloy
US5169597 *Jan 28, 1991Dec 8, 1992Davidson James ABiocompatible low modulus titanium alloy for medical implants
US5190546 *Apr 9, 1991Mar 2, 1993Raychem CorporationMedical devices incorporating SIM alloy elements
US5290266 *Aug 14, 1992Mar 1, 1994General Electric CompanyFlexible coating for magnetic resonance imaging compatible invasive devices
US5324368 *May 19, 1992Jun 28, 1994Tsuyoshi MasumotoForming process of amorphous alloy material
US5372660 *Aug 26, 1993Dec 13, 1994Smith & Nephew Richards, Inc.Surface and near surface hardened medical implants
US5380375 *Nov 24, 1993Jan 10, 1995Koji HashimotoAmorphous alloys resistant against hot corrosion
US5460663 *Apr 20, 1994Oct 24, 1995Ykk CorporationHigh corrosion resistant amorphous alloys
US5482580 *Jun 13, 1994Jan 9, 1996Amorphous Alloys Corp.Joining of metals using a bulk amorphous intermediate layer
US5549797 *Mar 7, 1994Aug 27, 1996Koji HashimotoHighly corrosion-resistant amorphous alloys
US5578359 *Nov 29, 1994Nov 26, 1996Hewlett Packard CompanyMagnetic shielding garment for electro-biologic measurements
US5618359 *Dec 8, 1995Apr 8, 1997California Institute Of TechnologyMetallic glass alloys of Zr, Ti, Cu and Ni
US5647361 *Mar 1, 1993Jul 15, 1997Fonar CorporationMagnetic resonance imaging method and apparatus for guiding invasive therapy
US5706814 *Jun 20, 1996Jan 13, 1998Kabushiki Kaisha EgawaMethod of determining a position of a probe relative to a tooth using MRI
US5711363 *Feb 16, 1996Jan 27, 1998Amorphous Technologies InternationalDie casting of bulk-solidifying amorphous alloys
US5735975 *Feb 21, 1996Apr 7, 1998California Institute Of TechnologyQuinary metallic glass alloys
US5769861 *Sep 12, 1996Jun 23, 1998Brainlab Med. Computersysteme GmbhMethod and devices for localizing an instrument
US5772803 *Aug 26, 1996Jun 30, 1998Amorphous Technologies InternationalTorsionally reacting spring made of a bulk-solidifying amorphous metallic alloy
US5797443 *Sep 30, 1996Aug 25, 1998Amorphous Technologies InternationalMethod of casting articles of a bulk-solidifying amorphous alloy
US5803996 *May 21, 1996Sep 8, 1998Research Development Corporation Of JapanRod-shaped or tubular amorphous Zr alloy made by die casting and method for manufacturing said amorphous Zr alloy
US5823778 *Jun 9, 1997Oct 20, 1998The United States Of America As Represented By The Secretary Of The Air ForceImaging method for fabricating dental devices
US5842858 *May 13, 1996Dec 1, 1998Artma Biomedical, Inc.Method of imaging a person's jaw and a model therefor
US5895401 *Apr 26, 1996Apr 20, 1999Daum GmbhControlled-artifact magnetic resonance instruments
US5976274 *Jan 22, 1998Nov 2, 1999Akihisa InoueSoft magnetic amorphous alloy and high hardness amorphous alloy and high hardness tool using the same
US5980652 *Feb 23, 1998Nov 9, 1999Research Developement Corporation Of JapanRod-shaped or tubular amorphous Zr alloy made by die casting and method for manufacturing said amorphous Zr alloy
US6027586 *Mar 17, 1994Feb 22, 2000Tsuyoshi MasumotoForming process of amorphous alloy material
US6077367 *Feb 19, 1998Jun 20, 2000Alps Electric Co., Ltd.Method of production glassy alloy
US6306228 *Jun 24, 1999Oct 23, 2001Japan Science And Technology CorporationMethod of producing amorphous alloy excellent in flexural strength and impact strength
US6675033 *Mar 24, 2000Jan 6, 2004Johns Hopkins University School Of MedicineMagnetic resonance imaging guidewire probe
US6714809 *Nov 20, 2001Mar 30, 2004Surgi-Vision, Inc.Connector and guidewire connectable thereto
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7684860Mar 23, 2007Mar 23, 2010Medtronic, Inc.Components for reducing image distortion
US7890165Feb 16, 2010Feb 15, 2011Medtronic, Inc.Implantable medical device with reduced MRI image distortion
US7927737Mar 23, 2007Apr 19, 2011Medtronic, Inc.Implantable medical device and lithium battery
US8014867Sep 6, 2011Cardiac Pacemakers, Inc.MRI operation modes for implantable medical devices
US8032228Oct 4, 2011Cardiac Pacemakers, Inc.Method and apparatus for disconnecting the tip electrode during MRI
US8057530Nov 15, 2011Tyco Healthcare Group LpMedical devices with amorphous metals, and methods therefor
US8086321Dec 27, 2011Cardiac Pacemakers, Inc.Selectively connecting the tip electrode during therapy for MRI shielding
US8131368Mar 23, 2007Mar 6, 2012Medtronic, Inc.Implantable medical device with material for reducing MRI image distortion
US8160717Apr 17, 2012Cardiac Pacemakers, Inc.Model reference identification and cancellation of magnetically-induced voltages in a gradient magnetic field
US8311637Feb 6, 2009Nov 13, 2012Cardiac Pacemakers, Inc.Magnetic core flux canceling of ferrites in MRI
US8527046Sep 21, 2004Sep 3, 2013Medtronic, Inc.MRI-compatible implantable device
US8543207Jul 8, 2011Sep 24, 2013Cardiac Pacemakers, Inc.MRI operation modes for implantable medical devices
US8548591Feb 16, 2012Oct 1, 2013Medtronic Inc.Implantable medical device
US8554335Jul 19, 2011Oct 8, 2013Cardiac Pacemakers, Inc.Method and apparatus for disconnecting the tip electrode during MRI
US8565874Oct 19, 2010Oct 22, 2013Cardiac Pacemakers, Inc.Implantable medical device with automatic tachycardia detection and control in MRI environments
US8571661Sep 28, 2009Oct 29, 2013Cardiac Pacemakers, Inc.Implantable medical device responsive to MRI induced capture threshold changes
US8639331Dec 16, 2009Jan 28, 2014Cardiac Pacemakers, Inc.Systems and methods for providing arrhythmia therapy in MRI environments
US8886317Sep 16, 2013Nov 11, 2014Cardiac Pacemakers, Inc.MRI operation modes for implantable medical devices
US8897875Nov 22, 2011Nov 25, 2014Cardiac Pacemakers, Inc.Selectively connecting the tip electrode during therapy for MRI shielding
US8923969Sep 27, 2013Dec 30, 2014Medtronic, Inc.Implantable medical device
US8977356Jan 23, 2014Mar 10, 2015Cardiac Pacemakers, Inc.Systems and methods for providing arrhythmia therapy in MRI environments
US9357996 *Mar 26, 2015Jun 7, 2016DePuy Synthes Products, Inc.Fixation device with magnesium core
US9381371Oct 20, 2013Jul 5, 2016Cardiac Pacemakers, Inc.Implantable medical device with automatic tachycardia detection and control in MRI environments
US20060210880 *Jan 31, 2006Sep 21, 2006Medtronic, Inc.Current collector
US20070248881 *Mar 23, 2007Oct 25, 2007Medtronic, Inc.Implantable medical device and lithium battery
US20080103543 *Oct 31, 2006May 1, 2008Medtronic, Inc.Implantable medical device with titanium alloy housing
US20080125848 *Jun 29, 2007May 29, 2008Kusleika Richard SMedical devices with amorphous metals, and methods therefor
US20080190521 *Sep 5, 2005Aug 14, 2008Eidgenossische Technische Hochschule ZurichAmorphous Alloys on the Base of Zr and their Use
US20090139612 *Nov 21, 2008Jun 4, 2009Kun LuZr-based amorphous alloy and a preparing method thereof
US20090288741 *Nov 26, 2009Faliang ZhangAmorphous Alloy and A Preparation Method Thereof
US20100145183 *Feb 16, 2010Jun 10, 2010Medtronic, Inc.Implantable medical device
EP1632584A1 *Sep 6, 2004Mar 8, 2006Eidgenössische Technische Hochschule ZürichAmorphous alloys on the base of Zr and their use
WO2006026882A1 *Sep 5, 2005Mar 16, 2006Eidgenössische Technische Hochschule ZürichAmorphous alloys on the base of zr and their use
Classifications
U.S. Classification148/561
International ClassificationA61L31/18, A61B10/00, C22C14/00, C22C9/00, A61B10/02, A61L31/02, A61B17/32, C22C45/10, A61B17/86
Cooperative ClassificationA61L31/18, A61B17/866, A61B10/02, A61B17/3211, C22C9/00, C22C45/10, A61L31/026, C22C14/00
European ClassificationC22C9/00, A61B17/86M, A61L31/18, C22C45/10, A61L31/02F, C22C14/00