Method and apparatus for evaluating connective tissue conditions

• US 20070049808A1
• Filed: 09/01/2005
• Published: 03/01/2007
• Est. Priority Date: 09/01/2005
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Roessler, Blake, Morris, Michael, Dehring, Karen
• Granted Patent: US 7,729,749 B2
• Time in Patent Office: Days
• US Class Current: 600/315
• 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 5/413 Monitoring transplanted tissue or organ, e.g. for possible rejection reactions after a transplant
• CPC Class Codes: A61B 5/4514 Cartilage
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• 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 21/359 using near infrared light

Abstract

Methods and apparatus are provided for evaluating a connective tissue condition of a patient (e.g., a disease, a risk of developing a disease, a risk of developing a fracture, etc.). For example, an indicator associated with the connective tissue condition may be generated. First, tissue at a first location of the body of the patient is irradiated using a light source. The tissue may be irradiated in vivo through the skin or via an incision, for example. Alternatively, a biopsy of the tissue may be irradiated. Then, spectral content information for light scattered, reflected, or transmitted by the irradiated tissue is determined. The spectral content information may be used, at least in part, to generate an indicator associated with a condition of connective tissue at a second location of the body of the patient, the second location remote from the first location. The indicator may, for example, assist a physician in diagnosing or ruling out the connective tissue condition.

Claims

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

irradiating a portion of tissue of the patient using a light source, the tissue at a first location of the body of the patient;

receiving light from the portion of the tissue;

determining spectral content information associated with the received light; and

generating, based at least on the spectral content information, an indicator of a connective tissue condition associated with connective tissue at a second location of the body of the patient, the second location remote from the first location.

2. A method as defined in claim 1, wherein the portion of tissue from tissue at the first location comprises at least one of ocular tissue, nasal cartilage tissue, or ear cartilage tissue;

wherein the connective tissue at the second location comprises cartilage from at least one of a joint of the hand, a joint of the foot, a knee joint, a hip joint, a back joint, or a neck joint.

3. 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.

4. 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.

5. A method as defined in claim 1, wherein irradiating the portion of tissue of the patient using the light source comprises irradiating the portion of 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 tissue of the patient using the substantially monochromatic light source comprises at least one of:

irradiating the portion of tissue of the patient using a substantially monochromatic light source that produces light having a wavelength of substantially 785 nanometers;

or

irradiating the portion of tissue of the patient using a substantially monochromatic light source that produces light having a wavelength of substantially 830 nanometers.

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

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

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

10. 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.

11. 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.

12. A method as defined in claim 11, wherein determining the at least one intensity of the at least one band comprises at least one of:

fitting a curve to at least one band;

calculating an area of at least one band;

or

calculating a height of at least one band.

13. A method as defined in claim 11, 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.

14. A method as defined in claim 13, wherein generating the indicator of the connective tissue condition further comprises generating the indicator based at least in part on the first ratio.

15. A method as defined in claim 13, wherein the first band comprises at least one of:

a carbonate band;

a phosphate band;

a band at circa 1230 cm<sup>−

1</sup>;

a band at circa 1240 cm<sup>−

1</sup>;

a band at circa 1260 cm<sup>−

1</sup>;

or

a band at circa 1270 cm<sup>−

1</sup>;

and wherein the second band comprises at least one of;

a carbonate band;

a phosphate band;

a band at circa 1230 cm<sup>−

1</sup>;

a band at circa 1240 cm<sup>−

1</sup>;

a band at circa 1260 cm<sup>−

1</sup>;

or

a band at circa 1270 cm<sup>−

1</sup>.

16. 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.

17. 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 tissue of a patient irradiated by the light source, the tissue from a first location of a body of the patient;

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 a connective tissue condition based at least in part on the spectral content information, the connective tissue condition associated with connective tissue at a second location of the body of the patient, the second location remote from the first location.

18. An apparatus as defined in claim 17, wherein the computing device is configured to generate diagnostic information indicative of a cartilage tissue condition.

19. An apparatus as defined in claim 17, wherein the computing device is configured to generate diagnostic information indicative of a bone tissue condition.

20. An apparatus as defined in claim 17, wherein the light source comprises a substantially monochromatic light source.

21. An apparatus as defined in claim 20, wherein the light source produces light having a wavelength substantially between 700 nanometers and 1100 nanometers.

22. An apparatus as defined in claim 17, wherein the light source comprises an infrared light source.

23. An apparatus as defined in claim 17, wherein the light receiver comprises at least one of a microscope, an optical probe, or a lens coupled to a needle.

24. An apparatus as defined in claim 17, wherein the computing device comprises at least one of a digital circuit, an analog circuit, a mixed analog and digital circuit, or a processor coupled to a memory.

25. An apparatus as defined in claim 17, wherein the connective tissue condition comprises at least one of osteoarthritis, rheumatoid arthritis, chondromalacia, polychondritis, relapsing polychondritis, a genetic disorder, and an acquired disorder.

26. An apparatus as defined in claim 25, 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.

27. An apparatus as defined in claim 26, wherein the computing device is configured to, at least one of:

fit a curve to the at least one band;

determine an area of at least one band;

or

determine a height of at least one band.

28. An apparatus as defined in claim 17, 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.

29. An apparatus as defined in claim 17, 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.

30. A method for evaluating ocular tissue of a patient, the method comprising:

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

receiving light from the portion of the ocular tissue;

determining Raman spectra information associated with the received light; and

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

31. A method as defined in claim 30, wherein the Raman spectra information includes a plurality of bands corresponding to received light at one or more wavelengths;

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

32. A method as defined in claim 31, wherein determining the at least one intensity of the at least one band comprises at least one of:

fitting a curve to at least one band;

calculating an area of at least one band;

or

calculating a height of at least one band.

33. A method as defined in claim 31, 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.

34. A method as defined in claim 33, wherein generating the indicator of the connective tissue condition further comprises generating the indicator based at least in part on the first ratio.

35. An apparatus for evaluating ocular tissue of a patient, comprising:

a light source;

a Raman probe to receive light scattered from a portion of ocular 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 an ocular tissue condition based at least in part on the Raman spectra information.