Skin optical characterization device

• US 8,346,347 B2
• Filed: 09/15/2006
• Issued: 01/01/2013
• Est. Priority Date: 09/15/2005
• Status: Expired due to Fees

• Current Assignee: Palomar Medical Technologies Incorporated (Hologic Incorporated)
• Original Assignee: Palomar Medical Technologies Incorporated (Hologic Incorporated)
• Inventors: Altshuler, Gregory, Wang, Guangming, Zenzie, Henry
• Primary Examiner(s): Le, Long V.
• Assistant Examiner(s): HOFFA, ANGELA MARIE
• Application Number:
  US11/522,124
• Publication Number:
  US 20070060819A1
• Time in Patent Office: 2,300 Days
• Field of Search: 250/252.1
• US Class Current: 600/476
• 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 5/0082 adapted for particular medical purposes
• CPC Class Codes: A61B 5/443 Evaluating skin constituents, e.g. elastin, melanin, water
• CPC Class Codes: A61B 5/444 Evaluating skin marks, e.g. mole, nevi, tumour, scar
• CPC Class Codes: A61B 5/445 Evaluating skin irritation or skin trauma, e.g. rash, eczema, wound, bed sore
• CPC Class Codes: A61B 5/6843 Monitoring or controlling sensor contact pressure

Abstract

The present invention is generally directed to dermatological devices and methods in which one or more skin characteristics, such as the melanin index, are determined by analyzing radiation backscattered from a skin region illuminated by at least one, and preferably, two or more wavelengths, e.g., in a range of about 600 nm to about 900 nm. In many embodiments, the radiation is coupled to the skin via a waveguide, and an optical sensor is employed to ascertain contact between the waveguide (e.g., a waveguide surface adapted for contact with the skin) and the skin.

Claims

1. A dermatological treatment device, comprising:

a radiation source assembly configured to generate radiation having at least a first wavelength for tissue irradiation;

a waveguide coupled to said source assembly for directing the radiation from the radiation source assembly to a portion of tissue, and having a surface configured to irradiate said portion with said radiation;

a detector optically coupled to a sidewall of said waveguide and configured to detect radiation backscattered from said tissue in response to irradiation from said radiation source assembly and transmitted through the sidewall to the detector, said detector generating signals indicative of the level of radiation detected;

said sidewall being configured such that the level of backscattered radiation reaching the detector changes due to a change in the level of internal reflection of said backscattered radiation incident on said sidewall based on absence or presence of contact between said surface of the waveguide and the tissue; and

a processor configured to process the level of radiation detected and indicating at least one of contact of said surface of the waveguide with said tissue, absence of contact of said surface of the waveguide with said tissue, and one or more characteristics of said tissue.

2. The device of claim 1, wherein said radiation source assembly includes two or more radiation sources.

3. The device of claim 2, wherein a first radiation source is configured to produce radiation having said first wavelength and wherein a second radiation source is configured to produce radiation having a second wavelength.

4. The device of claim 1, wherein said radiation source assembly includes a single radiation source.

5. The device of claim 4, wherein said radiation source is configured to produce radiation having said first wavelength and radiation having a second wavelength.

6. The device of claim 1, wherein said radiation source assembly includes at least one of a light emitting diode (LED), a bi-color LED, a tunable radiation source, and a laser radiation source.

7. The device of claim 1, wherein said radiation source assembly is configured to generate radiation having a second wavelength.

8. The device of claim 7 wherein said first and second wavelengths are selected from a range of about 350 nm to about 1200 nm.

9. The device of claim 7 wherein said first and second wavelengths are selected from a range of about 600 nm to about 900 nm.

10. The device of claim 1 wherein said first wavelength is selected from a range of about 350 nm to about 1200 nm.

11. The device of claim 1 wherein said first wavelength is selected from a range of about 600 nm to about 900 nm.

12. The device of claim 1, wherein said detector is configured to detect a level of said radiation of said first wavelength.

13. The device of claim 1, wherein said detector is configured to send a signal to said processor indicating that said surface of said waveguide is not in contact with said tissue when the level of radiation detected is below a threshold.

14. The device of claim 1, wherein said detector is configured to send a signal to said processor indicating that said surface of said waveguide is in contact with said tissue when the level of radiation detected is above a threshold.

15. The device of claim 1, wherein said detector is configured to send a signal to said processor indicating that said surface of said waveguide is not in contact with said tissue when the level of radiation detected is above a threshold.

16. The device of claim 1, wherein said detector is configured to send a signal to said processor indicating that said surface of said waveguide is in contact with said tissue when the level of radiation detected is below a threshold.

17. The device of claim 1, wherein said waveguide is configured to totally internally reflect said backscattered radiation along the sidewall when said surface of said waveguide is not in contact with said tissue.

18. The device of claim 1, wherein said waveguide is configured to not totally internally reflect said backscattered radiation along the sidewall when said surface of said waveguide is in contact with said tissue.

19. The device of claim 1 wherein said waveguide is configured to totally internally reflect said backscattered radiation along the sidewall when said surface of said waveguide is in contact with said tissue.

20. The device of claim 1, wherein said waveguide is configured to not totally internally reflect said radiation along the sidewall when said surface of said waveguide is not in contact with said tissue.

21. The device of claim 1, wherein said radiation source assembly is configured to generate radiation having a second wavelength, and said detector is configured to detect a level of said radiation of said first wavelength and of said second wavelength.

22. The device of claim 1, further comprising:

a first polarizer configured to filter radiation of a first polarity from said radiation source assembly; and

a second polarizer configured to filter radiation of a second polarity entering said detector.

23. The device of claim 1, further comprising a filter disposed between the detector and the waveguide.

24. The device of claim 1, wherein said radiation source assembly is configured to generate radiation having three or more wavelengths.

25. The device of claim 24, wherein said radiation source assembly generates a wavelength selected from the group of about 645 nm, about 700 nm, and about 900 nm.

26. The device of claim 1 wherein said waveguide is formed of a material having an index of refraction in a range of about 1.4 to about 2.5.

27. The device of claim 1, further comprising:

a first polarizer configured to filter radiation of a first polarity from said radiation source assembly; and

a second polarizer configured to filter radiation of a second polarity entering said detector.

28. The device of claim 1, further comprising a filter disposed between said waveguide and said detector.

29. The device of claim 1, further comprising a controller coupled to said radiation source assembly, said controller configured to activate said radiation source assembly to produce radiation of different wavelengths at different times.

30. The device of claim 1, wherein said waveguide is an optical fiber.

31. The device of claim 1, further comprising at least one additional waveguide coupled to said source assembly.

32. The device of claim 31, wherein said at least one additional waveguide is an optical fiber.

33. The device of claim 1, wherein the one or more characteristics of the tissue comprises melanin optical density (MOD).

34. The device of claim 33, wherein said radiation source assembly generates a wavelength selected from the group of about 645 nm, about 700, and about 900 nm.

35. A dermatological device for determining a physical characteristic of a portion of skin, comprising

a radiation source assembly configured to generate radiation having at least a first wavelength;

a waveguide coupled to said source assembly for directing the radiation from the radiation source assembly to said portion of skin, and having a surface configured to irradiate said portion with said radiation;

a first detector coupled to said waveguide and configured to detect radiation backscattered from said portion of skin in response to irradiation from said radiation source assembly, said detector generating signals indicative of the level of radiation detected;

a second detector optically coupled to a sidewall of said waveguide for indicating contact of said surface of the waveguide with said portion of skin or absence of contact of said surface of the waveguide with said portion of skin;

said sidewall being configured such that the level of backscattered radiation reaching the second detector changes due to a change in the level of internal reflection of said backscattered radiation incident on said sidewall based on absence or presence of contact between said surface of the waveguide and the tissue; and

a processor in communication with said first detector and said second detector configured to process said signals from the first detector to determine the melanin optical density of said portion of skin, and configured to process signals from the second detector to determine contact or absence of contact of said surface of the waveguide with said portion of skin.

36. The device of claim 35, wherein said first wavelength is approximately 645 nm.

37. The device of claim 35, wherein said first wavelength is approximately 700 nm.

38. The device of claim 35, wherein said surface of said waveguide is adapted for contact with the tissue and inhibits transmission of radiation in absence of skin contact by total internal reflection of radiation reflected thereto from a sidewall of said waveguide.

39. The device of claim 35, further comprising a feedback mechanism in communication with said second detector and said radiation source assembly, wherein said feedback mechanism is capable of inhibiting activation of the radiation source assembly when the second detector indicates lack of contact between the waveguide and the source.

40. The device of claim 35, wherein said waveguide is an optical fiber.

41. The device of claim 35, further comprising at least one additional waveguide.

42. The device of claim 35, wherein a first radiation source produces radiation having the first wavelength and wherein a second radiation source produces radiation having a second wavelength.

43. The device of claim 42, wherein said first and second wavelengths are in a range of about 300 nm to about 1200 nm.

44. The device of claim 42, wherein said first and second wavelengths are in a range of about 600 nm to about 900 nm.

45. The device of claim 42, wherein said first and second wavelengths are in a range of about 630 nm to about 730 nm.

46. The device of claim 42, wherein said first wavelength is approximately 645 nm and said second wavelength is approximately 700 nm.

47. The device of claim 35, wherein said radiation source assembly generates a wavelength selected from the group of about 645 nm, about 700 nm, and about 900 nm.