Tissue marker for multimodality radiographic imaging

• US 8,966,735 B2
• Filed: 09/10/2013
• Issued: 03/03/2015
• Est. Priority Date: 11/17/2005
• Status: Active Grant

• Current Assignee: Breast-Med, Inc.
• Original Assignee: Breast-Med, Inc.
• Inventors: Bolan, Patrick, Garwood, Michael G., Nelson, Michael T., Halpern, Daniel A.
• Primary Examiner(s): Bryant, David P.
• Assistant Examiner(s): Koehler, Christopher M
• Application Number:
  US14/022,539
• Publication Number:
  US 20140187911A1
• Time in Patent Office: 539 Days
• Field of Search: 294/60, 294/63, 295/272, 366/108, 600/420, 600/431, 600/414, 600/424, 600/426
• US Class Current: 29/460
• 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 scaled 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. A radiographic marker capable of being permanently implanted in a living human or animal subject, the radiographic marker comprising:

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

a contrast agent positioned within the internal chamber, the contrast agent including a combination of a liquid and a gas, wherein the contrast agent is configured to produce a change in signal intensity in a magnetic resonance (MR) imaging modality with the radiographic marker fully implanted in the subject, wherein the nonbiodegradable solid material of the container includes a first magnetic susceptibility and the contrast agent includes a second magnetic susceptibility, wherein the nonbiodegradable solid material and the contrast agent 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.

2. The radiographic marker of claim 1, wherein the gas is other than ambient air to inhibit ambient air from being sealed within the internal chamber.

3. The radiographic marker of claim 2, wherein the gas includes nitrogen.

4. The radiographic marker of claim 1, wherein the gas includes a mixture of ambient air and one or more other gases.

5. The radiographic marker of claim 1, wherein the gas includes ambient air.

6. The radiographic marker of claim 1, wherein the gas includes nitrogen and one or more other gases.

7. The radiographic marker of claim 1, wherein the liquid is configured to produce the change in signal intensity in the MR imaging modality and the gas is configured to produce a signal in another imaging modality.

8. The radiographic marker of claim 7, wherein the other imaging modality includes an ultrasound based imaging modality.

9. The radiographic marker of claim 1, wherein the gas is dispersed within the liquid.

10. The radiographic marker of claim 1, wherein the nonbiodegradable solid material is configured to produce a signal in an imaging modality other than MR.

11. The radiographic marker of claim 1, wherein the fully implantable, biocompatible container includes a tube defining first and second end portions, and wherein the first end portion and the second end portion include at least one of a biocompatible adhesive and epoxy to seal the contrast agent within the internal chamber.

12. The radiographic marker of claim 1, wherein the fully implantable, biocompatible container includes a solid material including at least one of a glass material, a ceramic material, a polymer material, silicone, and carbon fiber.

13. The radiographic marker of claim 1, wherein the fully implantable, biocompatible container has a vial-shaped portion, the vial-shaped portion including an opening.

14. The radiographic marker of claim 13, wherein the fully implantable, biocompatible container includes a lid portion.

15. The radiographic marker of claim 14, wherein the lid portion is attached to the opening of the vial-shaped portion.

16. The radiographic marker of claim 1, wherein the fully implantable, biocompatible container includes:

a first portion including at least two openings; and

a second and third portion configured to be attached to the first portion at the at least two openings.

17. The radiographic marker of claim 16, wherein the second portion is attached to a first opening of the at least two openings and the third portion is attached to a second opening of the at least two opening.

18. The radiographic marker of claim 1, comprising a coating on an external surface of the fully, implantable, biocompatible container, the coating encapsulating the fully, implantable, biocompatible container.

19. The radiographic marker of claim 18, wherein the coating hermetically seals the fully, implantable, biocompatible container.

20. The radiographic marker of claim 1, wherein the radiographic marker is sized and shaped to fit within a lumen of a cannula configured to deliver the marker to a fully implanted location within the subject.

21. A radiographic marker capable of being permanently implanted in a living human or animal subject, the radiographic marker comprising:

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

a contrast agent positioned within the internal chamber, the contrast agent configured to produce a change in signal intensity in a magnetic resonance (MR) imaging modality with the radiographic marker fully implanted in the subject, wherein the solid material of the fully implantable, biocompatible container includes a first magnetic susceptibility and the contrast agent includes a second magnetic susceptibility, wherein the nonbiodegradable solid material and the contrast agent 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.

22. The radiographic marker of claim 21, wherein the radiographic marker is sized and shaped to fit within a lumen of a cannula configured to deliver the marker to a fully implanted location within the subject.

23. A method of manufacturing a radiographic marker capable of being permanently implanted in a living human or animal subject, the method comprising:

providing or obtaining a fully implantable, biocompatible container formed from a nonbiodegradable solid material, the fully implantable, biocompatible container defining an internal chamber;

at least partially filling the internal chamber with a contrast agent including a combination of a liquid and a gas, wherein the contrast agent is configured to produce a change in signal intensity in a magnetic resonance (MR) imaging modality with the radiographic marker fully implanted in the subject, wherein the nonbiodegradable solid material of the fully implantable, biocompatible container includes a first magnetic susceptibility and the contrast agent includes a second magnetic susceptibility, wherein the nonbiodegradable solid material and the contrast agent 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; and

sealing the contrast agent within the internal chamber.

24. The method of claim 23, wherein at least partially filling the internal chamber includes filling the internal chamber within a chamber filled with the gas.

25. The method of claim 23, wherein the gas is other than ambient air to inhibit ambient air from being sealed within the internal chamber.

26. The method of claim 23, wherein the gas is nitrogen.

27. The method of claim 23, wherein the gas is a mixture of ambient air and one or more other gases.

28. The method of claim 23, wherein the gas is ambient air.

29. The method of claim 23, wherein the gas is nitrogen and one or more other gases.

30. The method of claim 23, comprising mixing the liquid configured to produce the change in signal intensity in the MR imaging modality and the gas configured to produce a signal in another imaging modality, wherein sealing the contrast agent within the internal chamber includes sealing the mixture of the liquid and the gas within the internal chamber.

31. The method of claim 23, wherein the fully implantable, biocompatible container includes a first portion and a second portion, the first portion including at least one opening configured to access the internal chamber, and wherein sealing the contrast agent within the internal chamber includes attaching the second portion at the opening of the first portion.

32. The method of claim 23, wherein the fully implantable, biocompatible container includes:

a first portion including at least two openings; and

a second portion and a third portion configured to be attached to the first portion at the at least two openings, wherein sealing the contrast agent within the internal chamber includes attaching the second and third portions at respective openings of the first portion.

33. The method of claim 23, wherein the fully implantable, biocompatible container includes a first end portion including at least one opening, and wherein sealing the contrast agent within the internal chamber includes sealing the first end portion using at least one of a biocompatible adhesive and epoxy.

34. The method of claim 23, comprising coating the fully implantable, biocompatible container to encapsulate the fully implantable, biocompatible container.

35. The method of claim 23, comprising at least partially filling the internal chamber with the contrast agent within a chamber at a pressure other than ambient pressure.

36. The method of claim 23, comprising applying a therapeutic agent to an external surface of the fully implantable, biocompatible container.