Method and apparatus for the treatment of benign pigmented lesions

• US 20040167592A1
• Filed: 02/25/2004
• Published: 08/26/2004
• Est. Priority Date: 02/25/2003
• Status: Active Grant

• Current Assignee: TRIA Beauty Incorporated (Channel Investments, LLC)
• Original Assignee: TRIA Beauty Incorporated (Channel Investments, LLC)
• Inventors: Island, Tobin C., Grove, Robert E., Weckwerth, Mark V.
• Granted Patent: US 7,981,111 B2
• Time in Patent Office: Days
• US Class Current: 607/96
• CPC Class Codes: A61B 18/082 Probes or electrodes therefor
• CPC Class Codes: A61B 18/203 applying laser energy to the outside of the body
• CPC Class Codes: A61B 2017/00057 Light
• CPC Class Codes: A61B 2017/00061 spectrum
• CPC Class Codes: A61B 2017/00066 intensity
• CPC Class Codes: A61B 2017/00172 Pulse trains, bursts, intermittent continuous operation
• CPC Class Codes: A61B 2017/00734 battery operated
• CPC Class Codes: A61B 2018/00005 Cooling or heating of the probe or tissue immediately surrounding the probe
• CPC Class Codes: A61B 2018/00452 Skin
• CPC Class Codes: A61B 2018/00476 Hair follicles
• CPC Class Codes: A61B 2018/2261 with scattering, diffusion or dispersion of light
• CPC Class Codes: A61B 2090/065 for measuring contact or contact pressure

Abstract

Disclosed is an apparatus and method which employs an energy source, one or more switches, electronic control circuitry, and a surface that can be placed in contact with a region of a person'"'"'s skin containing a benign pigmented lesion. Within the apparatus, electrical current is passed through a heating element that is thermally coupled to the surface so that this surface is heated rapidly and then is subsequently cooled rapidly. By judicious choice of the rate of heating, maximum temperatures achieved, and rate of cooling, thermal injury to the skin can be confined primarily to the epidermal region of the skin in contact with the surface.

Claims

What. What is claimed:

We claim;

1. An apparatus for treatment of a benign pigmented lesion on a region of skin comprising:

an energy source;

a surface of the apparatus configured for contact with the benign pigmented lesion and capable of being rapidly heated and cooled;

an ohmic heating element within the apparatus and thermally coupled to the surface;

a heat removal element within the apparatus and thermally coupled to the surface;

electronic control circuitry responsive to an activation signal so that the energy source is coupled to the ohmic heating element to cause rapid heating of the surface and thereafter to permit rapid cooling of the surface;

whereby thermal injury to the region of skin in contact with the surface is limited primarily to an epidermal layer.

2. The apparatus of claim 1, further including one or more switches and wherein the activation signal is provided by the one or more switches.

3. The apparatus of claim 2, wherein the one or more switches includes a contact sensor.

4. The apparatus of claim 2, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

5. The apparatus of claim 4, wherein the one or more switches is a contact sensor.

6. The apparatus of claim 2, wherein the electronic control circuitry couples the energy source to the ohmic heating element so that the rapid heating heats the lesion to a temperature of at least 60 degrees Celsius in less than 200 milliseconds, and the subsequent rapid cooling cools the lesion to a temperature of less than 50 degrees Celsius in less than 500 milliseconds.

7. The apparatus of claim 6, wherein the one or more switches is a contact sensor.

8. The apparatus of claim 6, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

9. The apparatus of claim 8, wherein the one or more switches includes a contact sensor.

45. The apparatus of claim 1, wherein the energy source is coupled to the ohmic heating element for a selected period of time, and further wherein the heat removal element includes

a thermal insulating portion;

and

a heat absorbing portion;

wherein the thermal insulating portion is selected to have a thermal transfer rate so that it operates as a thermal insulator during at least a portion of the selected period of time, and as a thermal conductor following the selected period of time.

46. The apparatus of claim 45, wherein the thermal insulating portion is a layer selected from a group of materials including transparent tape, glass or mica, and the heat absorbing portion is selected from a block of metal, a phase change material, a thermo-electric module, or a finned heatsink.

10. A handheld, self-contained apparatus for causing controlled heat-induced thermal injury to a region of skin of a person comprising:

a housing configured for gripping by a person'"'"'s hand;

an energy source within the housing;

an ohmic heating element within the housing and thermally coupled to the surface;

one or more heat-removal elements within the housing and thermally coupled to the surface;

a surface of the housing configured for contact with skin;

electronic control circuitry responsive to an activation signal so that the energy source is coupled to the ohmic heating element to cause rapid heating of the surface and thereafter to permit rapid cooling of the surface;

whereby thermal injury to the region of skin in contact with the surface is limited primarily to an epidermal layer.

11. The apparatus of claim 10, including one or more switches which provide the activation signal.

12. The apparatus of claim 11, wherein the one or more switches includes a contact sensor.

13. The apparatus of claim 10, wherein the energy source comprises one or more batteries within the housing.

14. The apparatus of claim 11, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

15. The apparatus of claim 14, wherein the one or more switches includes a contact sensor.

16. The apparatus of claim 11, wherein the rapid heating and subsequent rapid cooling of the surface is adapted to provide thermal injury to the region of the skin suitable for treatment of a benign pigmented lesion.

17. The apparatus of claim 16, wherein the one or more switches includes a contact sensor.

18. The apparatus of claim 16, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

19. The apparatus of claim 18, wherein the one or more switches includes a contact sensor.

20. The apparatus of claim 16, wherein the electronic control circuitry couples the energy source to the ohmic heating element so that the rapid heating heats the lesion to a temperature of at least 60 degrees Celsius in less than 200 milliseconds, and the subsequent rapid cooling cools the lesion to a temperature of less than 50 degrees Celsius in less than 500 milliseconds.

21. The apparatus of claim 20, wherein the one or more switches includes a contact sensor.

22. The apparatus of claim 20, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

23. The apparatus of claim 22, wherein the one or more switches includes a contact sensor.

24. The apparatus of claim 11, wherein the one or more heat-removal elements includes a thermal battery.

25. The apparatus of claim 24, wherein the one or more switches includes a contact sensor.

26. The apparatus of claim 24, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

27. The apparatus of claim 26, wherein the one or more switches includes a contact sensor.

28. The apparatus of claim 24, wherein the rapid heating and subsequent rapid cooling of the surface is adapted to provide thermal injury to the region of the skin suitable for treatment of a benign pigmented lesion.

29. The apparatus of claim 28, wherein the one or more switches includes a contact sensor.

30. The apparatus of claim 28, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

31. The apparatus of claim 30, wherein the one or more switches includes a contact sensor.

32. The apparatus of claim 28 wherein the electronic control circuitry couples the energy source to the ohmic heating element so that the rapid heating heats the lesion to a temperature of at least 60 degrees Celsius in less than 200 milliseconds, and the subsequent rapid cooling cools the lesion to a temperature of less than 50 degrees Celsius in less than 500 milliseconds.

33. The apparatus of claim 32, wherein the one or more switches includes a contact sensor.

34. The apparatus of claim 32 wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

35. The apparatus of claim 34, wherein the one or more switches includes a contact sensor.

36. An apparatus for treatment of a benign pigmented lesion on a region of skin comprising:

an energy source;

a surface of the apparatus configured for contact with the benign pigmented lesion and capable of being rapidly heated and cooled;

an ohmic heating element within the apparatus and thermally coupled to the surface;

a heat removal element within the apparatus and thermally coupled to the surface, wherein the surface is capable of being heated more rapidly than the heat removal element;

electronic control circuitry responsive to an activation signal and which couples the energy source to the ohmic heating element at a power level or duration, or both, sufficient to cause rapid heating of the surface and thereafter permits rapid cooling of the surface;

whereby thermal injury to the region of skin in contact with the surface is limited primarily to an epidermal layer.

37. The apparatus of claim 36, further including one or more switches and wherein the activation signal is provided by the one or more switches.

38. The apparatus of claim 37, wherein the one or more switches includes a contact sensor.

39. The apparatus of claim 37, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

40. The apparatus of claim 39, wherein the one or more switches is a contact sensor.

41. The apparatus of claim 37, wherein the power level or duration, or both, are selected so that the rapid heating heats the lesion to a temperature of at least 60 degrees Celsius in less than 200 milliseconds, and the subsequent rapid cooling cools the lesion to a temperature of less than 50 degrees Celsius in less than 500 milliseconds.

42. The apparatus of claim 41, wherein the one or more switches is a contact sensor.

43. The apparatus of claim 41, wherein the surface is cooled below an average temperature of the skin and placed in contact with the skin prior to activation of the ohmic heating element.

44. The apparatus of claim 43, wherein the one or more switches includes a contact sensor.

47. A method of operating an apparatus for treatment of a benign pigmented lesion on a region of skin, wherein the apparatus includes an energy source, a surface configured for contact with the benign pigmented lesion and capable of being rapidly heated and rapidly cooled, an ohmic heating element, and a heat removal element, the method comprising the steps of:

thermally coupling the ohmic heating element to the surface in a manner so that the surface rises in temperature more rapidly than the heat removal element;

applying a designated amount of power to the ohmic heating element from the energy source to produce a rapid rise in temperature of the surface for a designated period of time;

removing power from the ohmic heating element following the designated period of time so that heat can flow between the surface and the heat removal element to provide a rapid cooling of the surface;

whereby, during operation of the apparatus, thermal injury to the region of skin in contact with the surface is limited primarily to an epidermal layer.

48. The method of claim 47, wherein the apparatus further includes one or more switches, and further including the step of controlling the application of power to the ohmic heating element with the one or more switches.

49. The method of claim 47, wherein the apparatus further includes a contact sensor capable of detecting substantial contact between the surface and the region of skin, and further including the step of inhibiting the application of power to the ohmic heating element unless the substantial contact is detected by the contact sensor.

50. The method of claim 48, wherein the designated amount of power is selected so that the rapid heating of the surface heats the lesion to a temperature of at least 60 degrees Celsius in less than 200 milliseconds, and the subsequent rapid cooling of the surface cools the lesion to a temperature of less than 50 degrees Celsius in less than 500 milliseconds.

51. The method of claim 48, including the steps of cooling the surface below an average temperature of the skin, and placing the surface in contact with the skin prior to applying power to the ohmic heating element.