Method and apparatus for evaluating connective tissue conditions

• US 20050119587A1
• Filed: 09/17/2004
• Published: 06/02/2005
• Est. Priority Date: 07/01/2003
• Status: Abandoned Application

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: University of Michigan
• Inventors: Chen, Tso-Ching, Crane, Nicole, Smukler, Abigail, Morris, Michael D., Goldstein, Steven A., Roessler, Blake, McCreadie, Barbara R.
• Application Number:
  US10/944,518
• Publication Number:
  US 20050119587A1
• Time in Patent Office: Days
• US Class Current: 600/562
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/4504 Bones A61B5/4547 takes precedence
• CPC Class Codes: A61B 5/4509 Bone density determination
• CPC Class Codes: A61B 5/4514 Cartilage
• CPC Class Codes: A61B 5/4523 Tendons
• CPC Class Codes: A61B 5/4533 Ligaments
• CPC Class Codes: G01N 2021/656 Raman microprobe
• CPC Class Codes: G01N 21/35 using infrared light G01N21/39 takes precedence
• CPC Class Codes: G01N 21/65 Raman scattering

Abstract

In a method for evaluating a connective tissue condition of a patient, an indicator of the supporting tissue condition may be generated. A portion of connective tissue of the patient is irradiated using a light source. The connective tissue may be irradiated in vivo through the skin or via an incision, for example. Alternatively, a biopsy of the connective tissue may be irradiated. Then, spectral content information for light scattered, reflected, or transmitted by the connective tissue is determined. The spectral content information is used, at least in part, to generate the indicator. The indicator may assist a physician in diagnosing or ruling out the connective tissue condition, determining a risk of developing a disease, monitoring the progression of a disease, monitoring a response to treatment, etc.

Claims

1. A method for evaluating a supporting tissue condition of a patient, the method comprising:

irradiating a portion of connective tissue of the patient using a light source;

receiving light from the portion of the connective tissue;

determining spectral content information associated with the received light; and

generating, based at least on the spectral content information, an indicator of the connective tissue condition.

2. A method as defined in claim 1, wherein generating the indicator of the connective tissue condition comprises generating an indicator of a bone tissue condition.

3. A method as defined in claim 1, wherein generating the indicator of the connective tissue condition comprises generating an indicator of a cartilage tissue condition.

4. A method as defined in claim 1, wherein irradiating the portion of connective tissue of the patient using the light source comprises irradiating the portion of connective tissue of the patient using a substantially monochromatic light source.

5. A method as defined in claim 4, wherein irradiating the portion of connective tissue of the patient using the substantially monochromatic light source comprises irradiating the portion of connective tissue of the patient using a substantially monochromatic light source that produces light having a wavelength substantially between 700 nanometers and 1100 nanometers.

6. A method as defined in claim 5, wherein irradiating the portion of connective tissue of the patient using the substantially monochromatic light source comprises irradiating the portion of connective tissue of the patient using a substantially monochromatic light source that produces light having a wavelength of substantially 785 nanometers.

7. A method as defined in claim 6, wherein irradiating the portion of connective tissue of the patient using the substantially monochromatic light source comprises irradiating the portion of connective tissue of the patient using a substantially monochromatic light source that produces light having a wavelength of substantially 830 nanometers.

8. A method as defined in claim 1, wherein irradiating the portion of connective tissue of the patient using the light source comprises irradiating the portion of connective tissue of the patient using an infrared light source.

9. A method as defined in claim 1, wherein irradiating the portion of connective tissue of the patient comprises at least one of irradiating the portion of connective tissue in vivo, irradiating the portion of the connective tissue through the skin of the patient, irradiating the portion of the connective tissue via an incision in the patient, and irradiating a biopsy of connective tissue removed from the patient.

10. A method as defined in claim 1, wherein receiving light from the portion of the connective tissue comprises at least one of receiving light scattered from the portion of the connective tissue, receiving light transmitted through the portion of the connective tissue, and receiving light reflected by the portion of the connective tissue.

11. A method as defined in claim 1, wherein determining spectral content information comprises at least one of determining Raman spectra and determining infrared spectra.

12. A method as defined in claim 1, wherein generating the indicator of the connective tissue condition comprises generating an indicator associated with at least one of osteoarthritis, rheumatoid arthritis, chondromalacia, polychondritis, relapsing polychondritis, a genetic disorder, and an acquired disorder.

13. A method as defined in claim 1, wherein the spectral content information includes a plurality of bands corresponding to received light at one or more wavelengths;

wherein generating the indicator of the connective tissue condition comprises determining at least one intensity of at least one band.

14. A method as defined in claim 13, wherein determining the at least one intensity of the at least one band comprises fitting a curve to at least one band.

15. A method as defined in claim 13, wherein determining the at least one intensity of the at least one band comprises calculating an area of at least one band.

16. A method as defined in claim 13, wherein determining the at least one intensity of the at least one band comprises calculating a height of at least one band.

17. A method as defined in claim 13, wherein generating the indicator of the connective tissue condition comprises:

determining a first intensity of at least a first band;

determining a second intensity of at least a second band; and

determining a first ratio of the first intensity and the second intensity.

18. A method as defined in claim 17, wherein generating the indicator of the connective tissue condition further comprises generating the indicator based at least in part on the first ratio.

19. A method as defined in claim 17, wherein the first band comprises a carbonate band and wherein the second band comprises a phosphate band.

20. A method as defined in claim 17, wherein the first band comprises a band associate and wherein the second band comprises a band at circa 1270 cm⁻

1.

21. A method as defined in claim 17, wherein determining the first intensity of the at least the first band comprises:

determining a third intensity of the first band;

determining a fourth intensity of a third band; and

generating the first intensity based on the third intensity and the fourth intensity.

22. A method as defined in claim 21, wherein determining the second intensity comprises determining an intensity of a band associated with a matrix of the connective tissue;

wherein determining the third intensity comprises determining an intensity of a carbonate band; and

wherein determining the fourth intensity comprises determining an intensity of a phosphate band.

23. A method as defined in claim 17, wherein generating the indicator of the connective tissue condition comprises:

determining a third intensity of at least a third band;

determining a fourth intensity of at least a fourth band;

determining a second ratio of the third intensity and the fourth intensity.

24. A method as defined in claim 23, wherein generating the indicator of the connective tissue condition further comprises wherein generating the indicator of the connective tissue condition based on the first ratio and the second ratio.

25. A method as defined in claim 1, further comprising determining whether the patient has the connective tissue condition based on the indicator of whether the patient has the connective tissue condition and on at least one of an age of the patient, height of the patient, a weight of the patient, prior weight history of the patient, a blood test, a synovial fluid test, a bone mineral density of the patient, an X-ray, prior medical history of the patient, and a family history of the patient.

26. An apparatus for evaluating a connective tissue condition of a patient, comprising:

a light source;

a light receiver to receive light from a portion of connective tissue of a patient irradiated by the light source;

a spectrum analyzer optically coupled to receive light received by the light receiver, the spectrum analyzer configured to generate spectral content information associated with the received light; and

a computing device communicatively coupled to the spectrum analyzer, the computing device configured to generate diagnostic information indicative of the connective tissue condition based at least in part on the spectral content information.

27. An apparatus as defined in claim 26, wherein the computing device is configured to generate diagnostic information indicative of a cartilage tissue condition.

28. An apparatus as defined in claim 26, wherein the computing device is configured to generate diagnostic information indicative of at least one of a bone tissue condition and a cartilage tissue condition.

29. An apparatus as defined in claim 26, wherein the light source comprises a substantially monochromatic light source.

30. An apparatus as defined in claim 29, wherein the light source produces light having a wavelength substantially between 700 nanometers and 1100 nanometers.

31. An apparatus as defined in claim 26, wherein the light source comprises an infrared light source.

32. An apparatus as defined in claim 26, wherein the light receiver comprises a microscope.

33. An apparatus as defined in claim 26, wherein the light receiver comprises an optical probe.

34. An apparatus as defined in claim 26, wherein the light receiver comprises a lens coupled to a needle.

35. An apparatus as defined in claim 34, wherein the light receiver further comprises at least one optical fiber coupled to the lens.

36. An apparatus as defined in claim 26, wherein the computing device comprises a digital circuit.

37. An apparatus as defined in claim 26, wherein the computing device comprises an analog circuit.

38. An apparatus as defined in claim 26, wherein the computing device comprises a mixed analog and digital circuit.

39. An apparatus as defined in claim 26, wherein the computing device comprises a processor coupled to a memory.

40. An apparatus as defined in claim 26, wherein the connective tissue condition comprises at least one of osteoarthritis, rheumatoid arthritis, chondromalacia, polychondritis, relapsing polychondritis, a genetic disorder, and an acquired disorder.

41. An apparatus as defined in claim 40, wherein the spectral content information includes a plurality of bands corresponding to received light at one or more wavelengths;

wherein the computing device is configured to determine at least one intensity of at least one band.

42. An apparatus as defined in claim 41, wherein the computing device is configured to fit a curve to the at least one band.

43. An apparatus as defined in claim 41, wherein the computing device is configured to determine an area of at least one band.

44. An apparatus as defined in claim 41, wherein the computing device is configured to determine a height of at least one band.

45. An apparatus as defined in claim 41, wherein the computing device is configured to determine a first intensity of at least a first band;

wherein the computing device is configured to determine a second intensity of at least a second band; and

wherein the computing device is configured to determine a first ratio of the first intensity and the second intensity.

46. An apparatus as defined in claim 26, wherein the computing device is configured to generate the diagnostic information indicative of the connective tissue condition further based on at least one of age of the patient, a height of the patient, a weight of the patient, a prior weight of the patient, blood test data, synovial fluid test data, a bone mineral density of the patient, data associated with an X-ray, prior medical history data, and family history data.

47. A method for evaluating a cartilage tissue condition of a patient, the method comprising:

irradiating a portion of cartilage tissue of the patient using a light source;

receiving light from the portion of the cartilage tissue;

determining Raman spectra information associated with the received light; and

generating, based at least on the Raman spectra information, an indicator of the cartilage tissue condition.

48. An apparatus for evaluating a cartilage tissue condition of a patient, comprising:

a light source;

a Raman probe to receive light scattered from a portion of cartilage tissue of a patient irradiated by the light source;

a spectrum analyzer coupled to receive light received by the light receiver and to determine Raman spectra information for the received light; and

a computing device coupled to the spectrum analyzer, the computing device configured to generate diagnostic information indicative of the cartilage tissue condition based at least in part on the Raman spectra information.