MRI-visible medical devices
View Patent ↗A medical device includes a body, a member in the body, and a contrast agent in the member. The device can be visible by magnetic resonance imaging.
1. A medical device, comprising:
a body formed of a polymer;
a plurality of sealed members comprising a material different from the body, the members being embedded within the body, wherein the plurality of sealed members comprise relatively small fibers having a length-to-width aspect ratio of at least 3:1; and
a contrast agent encapsulated within the sealed members, wherein the contrast agent is different than the sealed members;
wherein the contrast agent is visible by magnetic resonance imaging,
wherein the members are incorporated into the body by mixing the plurality of sealed members with the polymer to form a mixture prior to extrusion and extruding the mixture to form the body.
2. The device of claim 1 , wherein the contrast agent has a contrast to noise ratio greater than about 4 under magnetic resonance imaging.
3. The device of claim 1 , wherein the contrast agent comprises a liquid.
4. The device of claim 1 , wherein the contrast agent comprises a solid.
5. The device of claim 1 , wherein the contrast agent comprises a T1 relaxation time shortening agent.
6. The device of claim 1 , wherein the contrast agent comprises water and a chemical agent.
7. The device of claim 1 , wherein the contrast agent comprises a heavy metal complex.
8. The device of claim 7 , wherein the heavy metal complex comprises Gd-DTPA.
9. The device of claim 1 , wherein the contrast agent comprises glycerin.
10. The device of claim 1 , wherein the contrast agent comprises a T2 relaxation time shortening agent.
11. The device of claim 1 , wherein the members comprise a hollow fiber.
12. The device of claim 1 , wherein the members comprise a polymer material.
13. The device of claim 12 , wherein the polymer material is selected from a group consisting of polypropylene, polyethylene, Nylon, polyethyleneterephthalate, and polyacetonitrile.
14. The device of claim 1 , wherein the members comprise a metal.
15. The device of claim 1 , further comprising a solid chemical agent encapsulated by the members.
16. The device of claim 15 , wherein the solid chemical agent is radiopaque.
17. The device of claim 16 , wherein the solid chemical agent comprises a material selected from a group consisting of gold, tantalum, barium, bismuth, and tungsten.
18. The device of claim 1 , wherein the members extend helically about the body.
19. The device of claim 1 , wherein the device is a guidewire.
20. The device of claim 1 , wherein the device is a vascular graft.
21. The device of claim 1 , wherein the device is a stent-graft.
22. The device of claim 1 , wherein the device is a stent.
23. The device of claim 1 , wherein the device is a medical balloon.
24. The device of claim 1 , wherein the device is a balloon catheter.
25. The device of claim 1 , wherein the members comprise a material have low permeability.
26. A medical tubing, comprising:
a hollow body formed of a polymer;
a plurality of sealed members comprising a material different from the body, the sealed members being embedded within the body, wherein the plurality of sealed members comprise relatively small fibers having a length-to-width aspect ratio of at least 3:1; and
a contrast agent encapsulated within the sealed member, wherein the contrast agent is different than the sealed members;
wherein the contrast agent is visible by magnetic resonance imaging,
wherein the members are incorporated into the body by mixing the members with the polymer to form a mixture prior to extrusion and extruding the mixture to form the body.
27. The tubing of claim 26 , in the form of a medical catheter.
28. A method of making a medical device, the method comprising:
extruding a body comprising a polymer, and a plurality of sealed members comprising a material different from the body and having a contrast agent encapsulated within the member, wherein the contrast agent is different than the sealed members, wherein the sealed members comprise relatively short fibers having a length-to-width aspect ratio of at least 3:1;
wherein the sealed members are embedded within the body and the device is visible by magnetic resonance imaging.
29. The method of claim 28 , wherein the device has a contrast to noise ratio greater than about 4 under magnetic resonance imaging.
30. The method of claim 28 , wherein the body is a tubular member.
31. The method of claim 28 , wherein the contrast agent comprises a liquid.
32. The method of claim 28 , wherein the contrast agent comprises a solid.
33. A method of making a medical device, the method comprising:
forming a mixture comprising a first polymer, and a plurality of sealed members comprising a material different from the first polymer and having a contrast agent that is different from the sealed members and encapsulated within the sealed members, wherein the sealed members are relatively short fibers having a length-to-width aspect ratio of at least 3:1; and
forming the mixture into the medical device;
wherein the members are embedded within the first polymer.
34. The method of claim 33 , further comprising injecting the mixture into a mold.
35. The method of claim 33 , further comprising extruding the mixture.
36. The method of claim 33 , wherein the contrast agent comprises a liquid.
37. The method of claim 33 , wherein the contrast agent comprises a solid.