Magnetic resonance imaging coated assembly

• US 20040225213A1
• Filed: 05/03/2004
• Published: 11/11/2004
• Est. Priority Date: 01/22/2002
• Status: Abandoned Application

• Current Assignee: Biophan Technologies Incorporated
• Original Assignee: Biophan Technologies Incorporated
• Inventors: Gray, Robert W., Weiner, Michael L., Helfer, Jeffrey L., Wang, Xingwu, Greenwald, Howard J.
• Application Number:
  US10/838,116
• Publication Number:
  US 20040225213A1
• Time in Patent Office: Days
• US Class Current: 600/421
• CPC Class Codes: A61K 49/1818 particles, e.g. uncoated or non-functionalised microparticles or nanoparticles
• CPC Class Codes: A61N 1/16 Screening or neutralising undesirable influences from or using, atmospheric or terrestrial radiation or fields using atmospheric electricity or earth currents H05F3/00
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: B82Y 5/00 Nanobiotechnology or nanomedicine, e.g. protein engineering or drug delivery
• CPC Class Codes: G01R 33/286 involving passive visualization of interventional instruments, i.e. making the instrument visible as part of the normal MR process
• CPC Class Codes: H01B 11/10 Screens specially adapted for reducing interference from external sources
• CPC Class Codes: H01B 11/1083 the coating containing magnetic material
• CPC Class Codes: H01F 10/007 ultrathin or granular films H01F10/005 and H01F10/3227 take precedence; applying ultrathin or granular layers to substrates H01F41/301
• CPC Class Codes: H01F 10/324 Exchange coupling of magnetic film pairs via a very thin non-magnetic spacer, e.g. by exchange with conduction electrons of the spacer

Abstract

An assembly for shielding an implanted medical device from the effects of high-frequency radiation and for emitting magnetic resonance signals during magnetic resonance imaging. The assembly includes an implanted medical device and a magnetic shield comprised of nanomagnetic material disposed between the medical device and the high-frequency radiation. In one embodiment, the magnetic resonance signals are detected by a receiver, which is thus able to locate the implanted medical device within a biological organism.

Claims

1. A magnetic resonance imaging tracking assembly that comprises a medical device having a magnetic shield comprised of a layer of nanomagnetic material, means for contacting said magnetic shield with a first high frequency electromagnetic wave, means for modifying said first high frequency electromagnetic wave with said magnetic shield to produce a second high frequency electromagnetic wave, and means for transmitting said second high frequency electromagnetic wave from said layer of nanomagnetic material, wherein:

a. said medical device is disposed within a biological organism,

b. said nanomagnetic material has an average particle size of less than about 1000 nanometers,

c. said layer of nanomagnetic material has a saturation magnetization of from about 200 to about 26,000 Gauss,

d. said layer of nanomagnetic material is disposed between said first high frequency electromagnetic wave and said medical device,

e. said layer of nanomagnetic material has a thickness of less than about 2 microns,

f. said first high frequency electromagnetic wave has a frequency of from at least 21 megahertz to about 128 megahertz.

2. A magnetic resonance imaging tracking assembly that comprises a medical device having a magnetic shield, means for contacting said magnetic shield with a first electromagnetic wave, means for modifying said first electromagnetic wave with said magnetic shield to produce a second electromagnetic wave, and means for sensing said second electromagnetic wave wherein:

a. said medical device is disposed with a biological organism,

b. said magnetic shield is comprised of a layer of said nanomagnetic material, wherein;

i. said layer of nanomagnetic material is disposed between said first electromagnetic wave and said medical device,

ii. said nanomagnetic material has an average particle size of less than about 100 nanometers, and

iii. said layer of nanomagnetic material has a saturation magnetization of from about 200 to about 26,000 Gauss and a thickness of less than about 10 microns.

3. A magnetic resonance imaging tracking assembly as recited in claim 2, wherein said first electromagnetic wave is a pulsed frequency electromagnetic wave.

4. A magnetic resonance imaging tracking assembly as recited in claim 3, wherein said pulsed frequency electromagnetic wave has a pulse duration of from about 1 microsecond to about 100 milliseconds.

5. A magnetic resonance imaging tracking assembly as recited in claim 2, wherein said medical device is comprised of a conductor.

6. A magnetic resonance imaging tracking assembly as recited in claim 5, wherein said conductor is flexible, having a bend radius of less than 2 centimeters.

7. A magnetic resonance imaging tracking assembly that comprises a medical device having a magnetic shield comprised of nanomagnetic material, means for contacting said magnetic shield with a first electromagnetic wave, means for modifying said first electromagnetic wave to produce a second electromagnetic wave, and means for transmitting said second electromagnetic wave from the nanomagnetic material, wherein:

a. said layer of nanomagnetic material has a saturation magnetization of from about 200 to about 26,000 Gauss,

b. said first electromagnetic wave has a frequency of from at least about 21 megahertz to about 128 megahertz,

c. said nanomagnetic particles are at least triatomic, being comprised of a first distinct atom, a second distinct atom, and a third distinct atom.

8. A magnetic resonance imaging tracking assembly as recited in claim 7, further comprising means for sensing said second electromagnetic wave.

9. A magnetic resonance imaging tracking assembly as recited in claim 8, further comprising means for producing an image from said second electromagnetic wave.

10. A magnetic resonance imaging tracking assembly as recited in claim 9, wherein said first wave is a pulsed electromagnetic wave.

11. A magnetic resonance imaging tracking assembly as recited in claim 7, wherein said first distinct atom selected from the group consisting of iron, nickel, and cobalt.

12. A magnetic resonance imaging tracking assembly as recited in claim 11, wherein said second distinct atom is selected from the group consisting of silicon, aluminum, boron, platinum, tantalum, palladium, yttrium, zirconium, titanium, calcium, beryllium, barium, silver, gold, indium, lead, tin, antimony, germanium, gallium, tungsten, bismuth, strontium, magnesium, and zinc.

13. A magnetic resonance imaging tracking assembly as recited in claim 12, wherein said third distinct atom is selected from the group consisting of oxygen, nitrogen, carbon, fluorine, chlorine, hydrogen, helium, neon, argon, krypton, and xenon.

14. A magnetic resonance imaging tracking assembly as recited in claim 7, wherein said first distinct atom is iron.

15. A magnetic resonance imaging tracking assembly as recited in claim 14, wherein said second distinct atom is aluminum.

16. A magnetic resonance imaging tracking assembly as recited in claim 15, wherein said third distinct atom is nitrogen.

17. A magnetic resonance imaging tracking assembly as recited in claim 15, wherein said nanomagnetic particles are further comprised of a fourth distinct atom.

18. A magnetic resonance imaging tracking assembly as recited in claim 17, wherein said fourth distinct atom is oxygen.

19. A magnetic resonance imaging tracking assembly as recited in claim 14, further comprising means for producing said first electromagnetic wave.

20. A magnetic resonance imaging tracking assembly as recited in claim 14, further comprising means for cooling said medical device.