Tissue marker for multimodality radiographic imaging

• US 7,702,378 B2
• Filed: 11/17/2005
• Issued: 04/20/2010
• Est. Priority Date: 11/17/2005
• Status: Active Grant

• Current Assignee: Breast-Med, Inc.
• Original Assignee: Breast-Med, Inc.
• Inventors: Halpern, Daniel A., Garwood, Michael, Bolan, Patrick J., Nelson, Michael T.
• Primary Examiner(s): Casler; Brian
• Assistant Examiner(s): Luong; Peter
• Application Number:
  US11/281,801
• Publication Number:
  US 20070110665A1
• Time in Patent Office: 1,615 Days
• Field of Search: 600/414, 600/420, 600/424, 600/426, 600/431
• US Class Current: 600/414
• CPC Class Codes: A61B 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61B 2090/3908 Soft tissue, e.g. breast tissue
• CPC Class Codes: A61B 2090/3925 ultrasonic
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 2090/3958 emitting a signal
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61B 2090/397 electromagnetic other than visible, e.g. microwave
• CPC Class Codes: A61B 2090/3995 Multi-modality markers
• CPC Class Codes: A61B 8/481 involving the use of contrast agent, e.g. microbubbles introduced into the bloodstream analysis of echo signal exploiting properties of a contrast enhancer in devices for short-range imaging with acoustic waves G01S7/52039
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61K 49/0002 General or multifunctional contrast agents, e.g. chelated agents
• CPC Class Codes: A61K 49/0447 Physical forms of mixtures of two different X-ray contrast-enhancing agents, containing at least one X-ray contrast-enhancing agent which is a halogenated organic compound
• CPC Class Codes: A61K 49/18 characterised by a special physical form, e.g. emulsions, microcapsules, liposomes
• CPC Class Codes: A61K 49/223 Microbubbles, hollow microspheres, free gas bubbles, gas microspheres
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50
• CPC Class Codes: A61M 31/005 for contrast media
• CPC Class Codes: G01R 33/4812 MR combined with X-ray or computed tomography [CT]
• CPC Class Codes: G01R 33/4814 MR combined with ultrasound
• CPC Class Codes: G01R 33/5601 involving use of a contrast agent for contrast manipulation, e.g. a paramagnetic, super-paramagnetic, ferromagnetic or hyperpolarised contrast agent
• CPC Class Codes: H01F 41/02 for manufacturing cores, coils, or magnets H01F41/14 takes precedence; for dynamo-electric machines H02K15/00
• CPC Class Codes: H01F 41/0253 : for manufacturing permanent magnets
• CPC Class Codes: Y10T 29/49075 : including permanent magnet or core
• CPC Class Codes: Y10T 29/49888 : Subsequently coating
• CPC Class Codes: Y10T 29/4998 : Combined manufacture including applying or shaping of fluent material
• CPC Class Codes: Y10T 29/49982 : Coating

Abstract

An implantable tissue marker incorporates a contrast agent sealed within a chamber in a container formed from a solid material. The contrast agent is selected to produce a change, such as an increase, in signal intensity under magnetic resonance imaging (MRI). An additional contrast agent may also be sealed within the chamber to provide visibility under another imaging modality, such as computed tomographic (CT) imaging or ultrasound imaging.

Claims

1. An apparatus comprising:

a permanently implantable radiographic marker including;

a fully implantable, biocompatible container formed from a nonbiodegradable solid material and defining an internal chamber; and

a contrast agent sealed within the internal chamber, the contrast agent including a liquid material configured to produce a change in signal intensity in a magnetic resonance (MR) imaging modality with the marker fully implanted in a human or animal subject, wherein the solid material of the container includes a first magnetic susceptibility and the liquid material of the contrast agent includes a second magnetic susceptibility, wherein the solid material and the liquid material are configured such that the first and second magnetic susceptibilities are matched so that the first magnetic susceptibility is substantially equivalent to the second magnetic susceptibility, wherein the permanently implantable radiographic marker is sized and shaped to fit within a lumen of a cannula configured to deliver the permanently implantable radiographic marker to a fully implanted location within the human or animal subject.

2. The apparatus of claim 1, wherein the contrast agent comprises at least another material selected from the group consisting of gas materials, liquid materials, and gel materials.

3. The apparatus of claim 1, wherein the container is generally spherical or spheroid in shape.

4. The apparatus of claim 1, further comprising a therapeutic agent.

5. The apparatus of claim 1, wherein the solid material forming the container is configured to produce a signal in another imaging modality.

6. The apparatus of claim 1, wherein the first magnetic susceptibility of the solid material of the container is substantially equivalent to a magnetic susceptibility of surrounding tissue.

7. The apparatus of claim 1, wherein the second magnetic susceptibility of the liquid material of the contrast agent is substantially equivalent to a magnetic susceptibility of surrounding tissue.

8. The apparatus of claim 1, wherein the permanently implantable radiographic marker, as a whole, includes an overall magnetic susceptibility substantially equivalent to a magnetic susceptibility of surrounding tissue.

9. The apparatus of claim 1, wherein the liquid material of the contrast agent is configured to produce an increased signal intensity.

10. The apparatus of claim 9, wherein the liquid material of the contrast agent is configured to produce the increased signal intensity in a T1-weighted MR image.

11. The apparatus of claim 1, wherein the container comprises a tube defining first and second end portions, and wherein the first and second end portions are at least substantially sealed.

12. The apparatus of claim 11, wherein the tube is formed from a solid material selected from the group consisting of glass materials, polymer materials, silicone, and carbon fiber.

13. The apparatus of claim 1, wherein the solid material forming the container is configured to produce a signal in another imaging modality in conjunction with the contrast agent sealed within the internal chamber.

14. The apparatus of claim 13, wherein the solid material forming the container and the contrast agent sealed within the internal chamber have different acoustic impedance characteristics.

15. The apparatus of claim 1, wherein the contrast agent includes a gas bubble.

16. The apparatus of claim 15, wherein the contrast agent, including the liquid material and the gas bubble, includes a magnetic susceptibility similar to a magnetic susceptibility of surrounding tissue.

17. The apparatus of claim 1, wherein the contrast agent comprises a mixture of a first contrast agent selected to produce the change in signal intensity in the MR imaging modality and a second contrast agent selected to produce a signal in another imaging modality.

18. The apparatus of claim 17, wherein the other imaging modality is one of an ultrasound imaging modality, an X-ray imaging modality, a fluoroscopy imaging modality, an electrical impedance tomographic imaging modality, a magnetic source imaging (MSI) modality, an magnetic resonance spectroscopic (MRS) modality, a magnetic resonance mammographic (MRM) modality, a magnetic resonance angiographic (MRA) modality, a magnetoelectro-encephalographic (MEG) modality, a laser optical imaging modality, an electric potential tomographic (EPT) modality, a brain electrical activity mapping (BEAM) modality, an arterial contrast injection angiographic modality, a digital subtraction angiographic modality, a positron emission tomographic (PET) modality, and a single photon emission computed tomographic (SPECT) modality.

19. The apparatus of claim 17, wherein the first contrast agent comprises a paramagnetic material.

20. The apparatus of claim 19, wherein the first contrast agent comprises gadolinium.

21. The apparatus of claim 17, wherein the other imaging modality is a computed tomographic (CT) X-ray imaging modality.

22. The apparatus of claim 21, wherein the second contrast agent comprises iodine.

23. An apparatus comprising:

a permanently implantable fiducial marker including;

a fully implantable, biocompatible container formed from a nonbiodegradable solid material and defining an internal chamber;

a first contrast agent sealed within the internal chamber, the first contrast agent configured to produce an increase in signal intensity in a magnetic resonance (MR) imaging modality with the marker fully implanted in a human or animal subject; and

a second contrast agent sealed within the internal chamber, the second contrast agent configured to produce a signal in another imaging modality, wherein at least one of the first contrast agent or the second contrast agent includes a liquid material, and wherein the solid material of the container includes a solid material magnetic susceptibility and the liquid material of at least one of the first contrast agent or the second contrast agent includes a liquid material magnetic susceptibility, wherein the solid material and the liquid material are configured such that the solid material magnetic susceptibility and the liquid material magnetic susceptibility are matched so that the solid material magnetic susceptibility is substantially equivalent to the liquid material magnetic susceptibility, wherein the permanently implantable fiducial marker is sized and shaped to fit within a lumen of a cannula configured to deliver the permanently implantable fiducial marker to a fully implanted location within the human or animal subject.

24. The apparatus of claim 23, wherein the first and second contrast agents form a mixture.

25. The apparatus of claim 23, wherein the other imaging modality is one of an ultrasound imaging modality, an X-ray imaging modality, a fluoroscopy imaging modality, an electrical impedance tomographic imaging modality, a magnetic source imaging (MSI) modality, an magnetic resonance spectroscopic (MRS) modality, a magnetic resonance mammographic (MRM) modality, a magnetic resonance angiographic (MRA) modality, a magnetoelectro-encephalographic (MEG) modality, a laser optical imaging modality, an electric potential tomographic (EPT) modality, a brain electrical activity mapping (BEAM) modality, an arterial contrast injection angiographic modality, a digital subtraction angiographic modality, a positron emission tomographic (PET) modality, and a single photon emission computed tomographic (SPECT) modality.

26. The apparatus of claim 23, wherein the first and second contrast agents each comprise at least one material selected from the group consisting of gas materials, liquid materials, and gel materials.

27. The apparatus of claim 23, wherein the container is generally spherical or spheroid in shape.

28. The apparatus of claim 23, further comprising a therapeutic agent.

29. The apparatus of claim 23, wherein the solid material magnetic susceptibility of the container is substantially equivalent to a magnetic susceptibility of surrounding tissue.

30. The apparatus of claim 23, wherein the liquid material magnetic susceptibility of at least one of the first contrast agent or the second contrast agent is substantially equivalent to a magnetic susceptibility of surrounding tissue.

31. The apparatus of claim 23, wherein the permanently implantable fiducial marker, as a whole, includes an overall magnetic susceptibility substantially equivalent to a magnetic susceptibility of surrounding tissue.

32. The apparatus of claim 23, wherein the first contrast agent comprises a paramagnetic material.

33. The apparatus of claim 32, wherein the first contrast agent comprises gadolinium.

34. The apparatus of claim 23, wherein the other imaging modality is a computed tomographic (CT) X-ray imaging modality.

35. The apparatus of claim 34, wherein the second contrast agent comprises iodine.

36. The apparatus of claim 23, wherein the container comprises a tube defining first and second end portions, and wherein the first and second end portions are at least substantially sealed using a biocompatible adhesive.

37. The apparatus of claim 36, wherein the tube is formed from a nonbiodegradable solid material selected from the group consisting of glass materials, polymer materials, silicone, and carbon fiber.

38. The apparatus of claim 23, wherein at least one of the first contrast agent or the second contrast agent includes a gas bubble.

39. The apparatus of claim 38, wherein at least one of the first contrast agent or the second contrast agent, including the liquid material and the gas bubble, includes a magnetic susceptibility substantially equivalent to a magnetic susceptibility of surrounding tissue.

40. The apparatus of claim 23, wherein the liquid material of at least one of the first contrast agent or the second contrast agent is configured to produce an increased signal intensity.

41. The apparatus of claim 40, wherein the liquid material of the at least one of the first contrast agent or the second contrast agent is configured to produce the increased signal intensity in a T1-weighted MR image.

42. A method of identifying a location within a body of a patient, the method comprising:

fully implanting a marker proximate the location using a cannula, the marker comprising a fully implantable, biocompatible container formed from a solid nonbiodegradable material and defining an internal chamber, the marker further comprising a contrast agent sealed within the internal chamber, the contrast agent including a liquid material configured to produce an increase in signal intensity in a magnetic resonance (MR) imaging modality with the marker fully implanted in a human or animal subject, wherein the solid material of the container includes a first magnetic susceptibility and the liquid material of the contrast agent includes a second magnetic susceptibility, wherein the solid material and the liquid material are configured such that the first and second magnetic susceptibilities are matched so that the first magnetic susceptibility is substantially equivalent to the second magnetic susceptibility, wherein the marker is configured to fit within a lumen of the cannula; and

generating a first image of the location in the magnetic resonance (MR) imaging modality.

43. The method of claim 42, wherein the contrast agent comprises at least another material selected from the group consisting of gas materials, liquid materials, and gel materials.

44. The method of claim 42, wherein the container is generally spherical or spheroid in shape.

45. The method of claim 42, wherein the solid material forming the container is configured to produce a signal in another imaging modality.

46. The method of claim 42, wherein the first magnetic susceptibility of the solid material of the container is substantially equivalent to a magnetic susceptibility of surrounding tissue.

47. The method of claim 42, wherein the second magnetic susceptibility of the liquid material of the contrast agent is substantially equivalent to a magnetic susceptibility of surrounding tissue.

48. The method of claim 42, wherein the permanently implantable radiographic marker, as a whole includes an overall magnetic susceptibility substantially equivalent to a magnetic susceptibility of surrounding tissue.

49. The method of claim 42, wherein the container comprises a tube defining first and second end portions that are at least substantially sealed using a biocompatible adhesive.

50. The method of claim 49, wherein the tube is formed from a solid material selected from the group consisting of glass materials, polymer materials, silicone, and carbon fiber.

51. The method of claim 42, wherein the solid material forming the container is configured to produce a signal in another imaging modality in conjunction with the contrast agent sealed within the internal chamber.

52. The method of claim 51, wherein the solid material forming the container and the contrast agent sealed within the internal chamber have different acoustic impedance characteristics.

53. The method of claim 42, wherein the contrast agent includes a gas bubble.

54. The method of claim 53, wherein the contrast agent, including the liquid material and the gas bubble, includes a magnetic susceptibility substantially equivalent to a magnetic susceptibility of surrounding tissue.

55. The method of claim 42, wherein the liquid material of the contrast agent is configured to produce an increased signal intensity.

56. The method of claim 55, wherein the liquid material of the contrast agent is configured to produce the increased signal intensity in a T1-weighted MR image.

57. The method of claim 42, further comprising generating a second image of the location in another imaging modality, wherein the contrast agent comprises a mixture of a first contrast agent configured to produce the increase in signal intensity in the MR imaging modality and a second contrast agent configured to produce a signal in the other imaging modality.

58. The method of claim 57, wherein the other imaging modality is one of an ultrasound imaging modality, an X-ray imaging modality, a fluoroscopy imaging modality, an electrical impedance tomographic imaging modality, a magnetic source imaging (MSI) modality, an magnetic resonance spectroscopic (MRS) modality, a magnetic resonance mammographic (MRM) modality, a magnetic resonance angiographic (MRA) modality, a magnetoelectro-encephalographic (MEG) modality, a laser optical imaging modality, an electric potential tomographic (EPT) modality, a brain electrical activity mapping (BEAM) modality, an arterial contrast injection angiographic modality, a digital subtraction angiographic modality, a positron emission tomographic (PET) modality, and a single photon emission computed tomographic (SPECT) modality.

59. The method of claim 57, wherein the first contrast agent comprises a paramagnetic material.

60. The method of claim 59, wherein the first contrast agent comprises gadolinium.

61. The method of claim 57, wherein the other imaging modality is a computed tomographic (CT) X-ray imaging modality.

62. The method of claim 61, wherein the second contrast agent comprises iodine.