Therapeutic light source and method

• US 20020029071A1
• Filed: 03/23/2001
• Published: 03/07/2002
• Est. Priority Date: 03/23/2000
• Status: Active Grant

• Current Assignee: The Lotus Global Group, Inc.
• Original Assignee: Photo Therapeutics Limited (Gadsden Properties, Inc.)
• Inventors: Whitehurst, Colin
• Granted Patent: US 6,645,230 B2
• Time in Patent Office: Days
• US Class Current: 607/88
• CPC Class Codes: A61N 2005/005 for cooling the radiator
• CPC Class Codes: A61N 2005/0611 Vagina
• CPC Class Codes: A61N 2005/0636 Irradiating the whole body
• CPC Class Codes: A61N 2005/0642 Irradiating part of the body at a certain distance
• CPC Class Codes: A61N 2005/0644 Handheld applicators
• CPC Class Codes: A61N 2005/0645 Applicators worn by the patient
• CPC Class Codes: A61N 2005/0647 the applicator adapted to be worn on the head
• CPC Class Codes: A61N 2005/0652 Arrays of diodes
• CPC Class Codes: A61N 2005/0662 Visible light
• CPC Class Codes: A61N 5/0601 Apparatus for use inside the body
• CPC Class Codes: A61N 5/0613 Apparatus adapted for a specific treatment
• CPC Class Codes: A61N 5/0617 Hair treatment
• CPC Class Codes: A61N 5/062 Photodynamic therapy, i.e. excitation of an agent

Abstract

A therapeutic light source, for example for photodynamic therapy (PDT), comprises an air-cooled array of LED'"'"'s (L_x,y), the air being vented in the vicinity of the array. The array may be mounted at the distal end of a hand piece suitable for invasive therapy. The LED'"'"'s may be coupled to a light guide (W, L). The emission spectra of the LED'"'"'s may be substantially limited to the range 550 to 660 nm, and preferably to one of the ranges 590 to 640 nm, 560 to 644 nm, 650 to 660 nm, and 550 to 570 nm. The therapeutic light source may comprise a non-planar array of light-emitting diodes L conforming with the shape of an external area to be treated or diagnosed. The therapeutic light source may comprise a non-planar array of independently switchable red and blue light-emitting diodes L_R, L_B, mounted on a flexible backing.

Claims

1. A light source for therapy and/or diagnosis, comprising an array of light-emitting diodes mounted on a flexible backing, the array including light-emitting diodes of a first type having a first emission spectrum and light-emitting diodes of a second type having a second emission spectrum different from the first emission spectrum.

2. A light source according to claim 1, wherein said light-emitting diodes of the first type are independently switchable from said light-emitting diodes of the first type.

3. A light source according to claim 1 or 2, wherein said first emission spectrum is substantially in the range 370 to 450 nm.

4. A light source according to claim 3, wherein said first emission spectrum is substantially in the range 400 to 430 nm.

5. A light source according to any preceding claim, wherein said second emission spectrum is substantially in the range 620 to 700 nm.

6. Use of a light source according to any preceding claim, in the treatment of a pre-cancerous condition.

7. Use according to claim 6, wherein said pre-cancerous condition is an actinic keratosis.

8. Use of a light source according to any one of claims 1 to 5, for the treatment of a non-melanoma.

9. Use according to claim 8, wherein said non-melanoma is a basal cell or squamous cell carcinoma.

30. A light source as claimed in any preceding claim, wherein the diodes are thermally coupled to one or more heatsinks.

53. A light source as claimed in any preceding claim, wherein said LED'"'"'s include a first set of LED'"'"'s and a second set of LED'"'"'s having different emission spectra from said first set.

57. Use of a light source as claimed in any preceding claim, for cosmetic treatment of a patient.

61. Use of a light source as claimed in any one of claims 1 to 56, for medical treatment of a patient.

62. Use as claimed in claim 61, for photodynamic treatment of a patient.

63. Use as claimed in claim 62, in the treatment of one or more of actinic/solar keratoses, Bowen'"'"'s disease, superficial basal cell carcinoma, squamous cell carcinoma, intraepithelial carcinoma, mycosis fungoides, T-cell lymphoma, acne and seborrhoea, eczema, psoriasis, nevus sebaceous, gastrointestinal conditions (e.g. Barratt'"'"'s oesophagus and colorectal carcinomas), gynaecological disorders (e.g. VIN, CIN and excessive uterine bleeding), oral cancers (e.g. pre-malignant or dyplastic lesions and squamous cell carcinomas), viral infections such as herpes simplex, molluscum contagiosum, and warts (recalcitrant, verruca vulgaris or verruca plantaris), alopecia areata, or hirsutism.

10. A light source for therapy and/or diagnosis, comprising a non-planar array of discrete light-emitting diodes mounted on a head portion for attachment to the head of a patient such that light is emitted onto the face of the patient.

11. A light source for therapy and/or diagnosis, comprising a first rigid array of light-emitting diodes, a second rigid array of light emitting diodes movably connected to an edge of the first array and a third rigid array of light-emitting diodes movably connected to another edge of the first array.

12. A light source as claimed in claim 11, further including a fourth array of light-emitting diodes movably to a further edge of the first array.

13. A light source as claimed in claim 11 or 12, arranged for treatment of the face and/or scalp.

15. A light source as claimed in claim 14, wherein said support includes a further array of light-emitting diodes.

16. A light source as claimed in claim 15, wherein said further array comprises a plurality of sections which are independently switchable.

19. A light source as claimed in claim 18, wherein the aperture and housing are dimensioned to allow one or both elbows of the patient to be inserted into the housing.

14. A light source for therapy and/or diagnosis, comprising a support for supporting the patient and an array of light-emitting diodes mounted on the curved inner surface of a rigid cover arranged to cover at least part of the length of a patient when supported by the support.

17. A light source as claimed in any one of claims 14 to 16, wherein said further array is planar.

18. A light source for therapy or diagnosis of a patient, comprising an array of light-emitting diodes arranged within a housing, and an aperture allowing a part of the patient'"'"'s body to be inserted into the housing, the array being arranged to direct light onto the part of the patient'"'"'s body when inserted into the housing.

20. A light source for therapy or diagnosis of a patient, comprising a plurality of independently switchable co-planar arrays of light-emitting diodes.

21. A light source for therapy or diagnosis of a patient, comprising a housing in the form of a trapezoid prism open at the base and having an upper inner surface carrying an array of light-emitting diodes.

22. A light source as claimed in claim 21, wherein at least one of the inner side faces is reflective.

23. A light source as claimed in claim 21, wherein at least one of the inner side faces carries a further array of light-emitting diodes.

25. A light source as claimed in claim 24, wherein said surface is substantially cylindrical.

26. A light source as claimed in claim 24, wherein said surface is substantially spherical.

29. A light source as claimed in claim 27 or 28, arranged so that light from the light-emitting diodes has a spatial intensity fluctuation of approximately 10% or less in the treatment field.

31. A light source as claimed in claim 27, wherein the diodes are mounted at the distal end of a passage for carrying the air from the proximal to the distal end.

32. A light source as claimed in claim 31, including a fan mounted at the proximal end of the passage.

33. A light source as claimed in claim 31 or claim 32, wherein the distal end is dimensioned so as to be locatable proximate a cervix such that light from the diode array is incident on the cervix.

34. A light source as claimed in claim 33, wherein the distal end is concave so as to fit over the cervix.

36. A light source according to claim 35, including a parallel-sided light guide coupled to the tapered light guide so that the light emitted by the light-emitting diodes is concentrated into the parallel-sided light guide.

38. A light source as claimed in claim 37, wherein the diodes are thermally coupled to thermoelectric cooling means.

39. A light source as claimed in claim 35 or 37, wherein the parallel-sided light guide comprises one or more optical fibres and/or liquid light guides.

24. A light source for therapy or diagnosis of a patient, comprising an intraluminal probe carrying on a surface thereof an array of discrete light-emitting diodes.

27. A therapeutic light source, comprising an array of light-emitting diodes arranged so that light from the light-emitting diodes is incident directly on the treatment field with an intensity of at least approximately 10 mW/cm², and means for cooling the diodes by forced air convection.

54. A light source as claimed in any one of claims 27 to 36 and 40 to 52, or claim 53 when dependent thereon, wherein the array is mounted on a flexible circuit board.

28. A therapeutic light source, comprising an array of discrete light-emitting diodes arranged to give an output intensity of at least approximately 10 mW/cm², and means for cooling the diodes by forced air convection.

35. A therapeutic light source, comprising an array of discrete light emitting diodes coupled to a tapered light guide arranged to concentrate light emitted by the light-emitting diodes.

37. A therapeutic light source, comprising an integrated array of light emitting diodes coupled directly to a parallel-sided light guide.

40. A therapeutic light source comprising an array of light emitting diodes having emission wavelengths substantially within the range 550 to 660 nm.

41. A light source as claimed in claim 40, wherein the emission wavelengths are substantially within the range 590 to 640 nm.

42. A light source as claimed in claim 41, wherein the diodes are of aluminium indium gallium phosphide/gallium phosphide die material.

43. A light source as claimed in claim 42, wherein the emission wavelengths are substantially within the range 560 to 644 nm.

44. A light source as claimed in claim 43, wherein the diodes are of aluminium indium gallium phosphide/gallium arsenic die material.

45. A light source as claimed in claim 42, wherein the emission wavelengths are substantially within the range 650 to 660 nm.

46. A light source as claimed in claim 45, wherein the diodes are of aluminium gallium arsenic die material.

47. A light source as claimed in claim 42, wherein the emission wavelengths are substantially within the range 550 to 570 nm.

48. A light source as claimed in claim 47, wherein the diodes are of gallium phosphide die material.

50. A light source as claimed in claim 49, wherein the diodes are of indium gallium nitride die material.

49. A therapeutic light source comprising an array of LED'"'"'s with peak emission spectra of approximately 470 nm, 505 nm or 525 nm.

51. A therapeutic light source comprising an array of LED'"'"'s with peak emission spectra of approximately 430 nm.

52. A light source as claimed in claim 51, wherein the diodes are of gallium nitride/silicon die material.

55. A therapeutic light source, comprising an LED array including a first set of LED'"'"'s and an independently switchable second set of LED'"'"'s having different emission spectra from said first set.

58. Use as claimed in claim 57, for photodynamic treatment of the patient.

59. Use as claimed in claim 58, for portwine stain removal, or hair restoration or removal.

60. Use as claimed in claim 57, for skin rejuvenation, wrinkle removal or biostimulation.

56. A light source for therapy or diagnosis, comprising an LED array including a first set of LED'"'"'s and a second, spatially distinct set of LED'"'"'s independently switchable from said first set.

64. A light source for therapy or diagnosis substantially as herein described with reference to and/or as shown in FIGS. 1 to 4, or FIG. 5, or FIG. 6, or FIG. 7, or FIG. 8, or FIG. 9, or FIGS. 10a and 10b, or FIGS. 11a to 11c, or FIG. 12, or FIG. 13, or FIG. 14, or FIG. 15, or FIGS. 16a and 16b, or FIGS. 17a and 17b, or FIGS. 18a and 18b, or FIGS. 19a and 19b, or FIGS. 20a and 20b, or FIG. 21, or FIGS. 22a to 22c, or FIGS. 23a to 23c, or FIG. 24, or FIG. 25, or FIG. 26 of the accompanying drawings.