Medical device with markers for magnetic resonance visibility
Embodiments of the present invention relate to medical devices that provide a suitable disturbance of medical resonance images taken of the devices in order to enhance the visibility of the devices. In one embodiment, paramagnetic and/or ferromagnetic material is applied to a support structure of a device. The magnetic materials provide a suitable distortion of MRI images such that the device (or portions thereof) are easily visible and detectable.
1 . An implantable medical device, comprising:
a support structure formed such that magnetic field changes in a region immediately proximate the support structure, induced by a magnetic resonance imaging process, are substantially unobstructed by the support structure; and
a magnetic material coating at least part of the support structure.
2 . The implantable medical device of claim 1 wherein the implantable medical device comprises a stent, the support structure forming a generally tubular structure that is substantially non-magnetic, and wherein the magnetic material coats the generally tubular structure such that at least part of the generally tubular structure is visible during a magnetic resonance imaging procedure.
3 . The implantable medical device of claim 2 wherein the generally tubular structure is made of a metallic material.
4 . The implantable medical device of claim 3 wherein the metallic material is at least one of Nitinol, stainless steel, tantalum, niobium, titanium and copper.
5 . The implantable medical device of claim 2 wherein the generally tubular structure is made of at least one of a polymer and a ceramic.
6 . The implantable medical device of claim 2 wherein the generally tubular structure is made of a biodegradable material.
7 . The implantable medical device of claim 1 wherein the magnetic material is paramagnetic.
8 . The implantable medical device of claim 1 wherein the magnetic material is ferromagnetic.
9 . The implantable medical device of claim 1 wherein the magnetic material includes at least one of iron, dysprosium, gadolinium, terbium, copper, cobalt, manganese, chromium and nickel.
10 . The implantable medical device of claim 2 wherein the generally tubular structure includes an end portion and the magnetic material is applied to the end portion.
11 . The implantable medical device of claim 2 wherein the generally tubular structure includes a first end portion and a second end portion and the magnetic material is applied only to the first end portion and the second end portion.
12 . A stent comprising:
a generally tubular structure made of a metallic material that is substantially non-magnetic; and
means for rendering the generally tubular structure visible during a magnetic resonance imaging procedure.
13 . The stent of claim 12 wherein the metallic material is at least one of Nitinol, stainless steel, tantalum, niobium, titanium and copper.
14 . The stent of claim 12 wherein the means for rendering is a paramagnetic material.
15 . The stent of claim 12 wherein the means for rendering is a ferromagnetic material.
16 . The stent of claim 12 wherein the means for rendering includes a material that is at least one of iron, dysprosium, gadolinium, terbium, copper, cobalt, manganese, chromium and nickel.
17 . The stent of claim 12 wherein the generally tubular structure includes an end portion and the means for rendering is applied to the end portion.
18 . The stent of claim 12 wherein the generally tubular structure includes a first end portion and a second end portion and the means for rendering is applied to the first end portion and the second end portion.
19 . A method for making an implantable medical device, comprising:
forming a support structure such that magnetic field changes in a region immediately proximate the support structure, inducing by a magnetic resonance imaging process, are substantially unobstructed by the support structure; and
applying a magnetic material to at least part of the support structure such that the support structure is visible during a magnetic resonance imaging procedure.
20 . The method of claim 19 wherein applying comprises using a plasma immersion ion implantation process.
21 . The method of claim 20 wherein applying further comprises shielding a portion of the support structure so that the magnetic material is applied to only an end portion of the support structure.
22 . The method of claim 20 wherein applying further comprises shielding the support structure so that the magnetic material is only applied to a first end portion and a second end portion of the support structure.
23 . The method of claim 19 wherein the support structure is made of a metallic material.
24 . The method of claim 23 wherein the metallic material is at least one of Nitinol, stainless steel, tantalum, niobium, titanium and copper.
25 . The method of claim 19 wherein the support structure is made of at least one of a polymer and a ceramic.
26 . The method of claim 19 wherein the support structure is made of a biodegradable material.
27 . The method of claim 19 wherein the magnetic material is paramagnetic.
28 . The method of claim 19 wherein the magnetic material is ferromagnetic.
29 . The method of claim 19 wherein the magnetic material includes at least one of iron, dysprosium, gadolinium, terbium, copper, cobalt, manganese, chromium and nickel.
30 . An elongated medical instrument comprising:
a support structure including a segment of material helically oriented about an axis of the instrument wherein the material is at least one of a polymer and a ceramic; and
a magnetic material applied to the segment.
31 . The instrument of claim 30 wherein the magnetic material is paramagnetic.
32 . The instrument of claim 30 wherein the magnetic material is ferromagnetic.
33 . The instrument of claim 30 wherein the magnetic material includes at least one of iron, dysprosium, gadolinium, terbium, copper, cobalt, manganese, chromium and nickel.