Claims
- 1. A medical guidewire for use in intravascular medical procedures and having proximal and distal ends, comprising:
a relatively long, flexible tubular sheath extending for substantially the length of the guidewire, the sheath being made of a polymer material having a high specific electric impedance; with proximal and distal ends of the tubular sheath being sealed shut; a proximal portion of the guidewire having a constant outer dimension, and a distal portion of the guidewire transitioning to a smaller outer dimension at the distal tip of the guidewire; and at least two markers positioned near the distal end of the guidewire, the markers all being surrounded by the tubular sheath, such that no portion of a marker is exposed to an exterior surface of the guidewire; the guidewire being compatible with use in both magnetic resonance and x-ray fluoroscopy environments, wherein the markers are visible under magnetic resonance due to susceptibility-induced magnetic field inhomogeneity; each marker having substantially the same size when viewed under magnetic resonance from any angle; and wherein the guidewire is formed entirely of non-metallic materials.
- 2. The medical guidewire of claim 1, further comprising at least two radiopaque markers visible under x-ray fluoroscopy.
- 3. The medical guidewire of claim 2, wherein the MR markers and x-ray markers are arranged adjacent each other in pairs.
- 4. The medical guidewire of claim 1, wherein the MR markers are formed of dysprosium salt.
- 5. The medical guidewire of claim 2, wherein the x-ray markers are formed of tungsten salt.
- 6. The medical guidewire of claim 1, wherein the markers are dual-function markers, visible under both MR and x-ray fluoroscopy.
- 7. The medical guidewire of claim 1, wherein the markers are formed of polymer material doped with dysprosium salt.
- 8. A medical guidewire for use in intravascular medical procedures and having proximal and distal ends, comprising:
a relatively long, thin core extending for substantially the length of the guidewire, the core being made of a glass having a high specific electric impedance; a polymer sheath surrounding the core; at least one marker affixed to the core and positioned near a distal end of the guidewire, wherein the marker is visible under magnetic resonance due to susceptibility-induced magnetic field inhomogeneity; and the markers all being surrounded by the tubular sheath, such that no portion of a marker is exposed to an exterior surface of the guidewire; and
wherein the guidewire is formed entirely of non-metallic materials.
- 9. The medical guidewire of claim 8, further comprising a plurality of reinforcing fibers affixed to the core to enhance the flexibility and torsion characteristics of the guidewire.
- 10. The medical guidewire of claim 1, further comprising a plurality of reinforcing fibers affixed to the polymer sheath to enhance the flexibility and torsion characteristics of the guidewire.
- 11. The medical guidewire of claim 10, wherein the material of the reinforcing fibers is selected from the group consisting of carbon, borium, aramide, and glass.
- 12. The medical guidewire of claim 8, wherein the material of the core is selected from the group consisting of fiberglass, silica, and quartz.
- 13. The medical guidewire of claim 8 wherein a distal segment of the glass core tapers to a diameter at the distal end of the guidewire that is smaller than the diameter of a major portion of the core.
- 14. The medical guidewire of claim 1, wherein the material of the marker is Dysprosium Oxide (Dy2O3).
- 15. The medical guidewire of claim 1, wherein the distal tip of the guidewire is bent slightly, to facilitate the selective steering of the guidewire along a desired vascular path.
- 16. The medical guidewire of claim 8, wherein the core has a breaking strength, said core being covered with a cladding for increasing said breaking strength.
- 17. The medical guidewire of claim 1, wherein at least a portion of the polymer sheath has a hydrophilic coating.
- 18. The medical guidewire of claim 8, wherein the core is formed of a plurality of glass core strands.
- 19. A medical guidewire for use in intravascular medical procedures and having proximal and distal ends, comprising:
a relatively long, flexible tubular sheath extending for substantially the length of the guidewire, the sheath being made of a polymer material having a high specific electric impedance; with proximal and distal ends of the tubular sheath being sealed shut; a proximal portion of, the guidewire having a constant outer dimension, and a distal portion of the guidewire transitioning to a smaller outer dimension at the distal tip of the guidewire; and at least one pair of two markers positioned near the distal end of the guidewire, the markers all being surrounded by the tubular sheath, such that no portion of a marker is exposed to an exterior surface of the guidewire; the guidewire being compatible with use in both magnetic resonance and x-ray fluoroscopy environments, one of each pair of markers being visible under magnetic resonance, and the other of each pair of markers being visible under x-ray fluoroscopy; wherein the marker is visible under magnetic resonance due to susceptibility-induced magnetic field inhomogeneity; and wherein the guidewire is formed entirely of non-metallic materials.
- 20. The medical guidewire of claim 13, wherein the material of one of each pair of the markers is Dysprosium Oxide (Dy2O3).
- 21. The medical guidewire of claim 13, wherein the material of the other of each pair of markers is stainless steel.
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority of U.S. Provisional Patent Application No. 60/211,157, filed Jun. 12, 2000.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
PCT/US01/18720 |
6/12/2001 |
WO |
|