Patent EA-002395-B1 (EA)
Title: Apparatus for selective photothermolysis of target tissue
Inventor: AZAAR ZION
IPC: A61B18/20
Filed: 1999-04-20
Abstract: 1. Apparatus for selective photothermolysis of a target tissue within the skin, the apparatus comprising: a housing having an opening therein, said housing forming a cavity enclosing a volume of air when said opening is placed in contact with said skin; a pulsable heat source disposed within said housing which heats the volume of air, such that heat is transferred to the skin by the heated air; and a pulsable source of narrow band electromagnetic radiation disposed in the cavity which irradiates the skin with narrow band electromagnetic radiation to selectively heat said target tissue. 2. Apparatus according to claim 1 wherein the pulsable heat source forms a temperature gradient in the air between the source and the skin. 3. Apparatus according to claim 1 or claim 2 wherein comprising a primary sensing and converting unit attached to said housing for sensing the temperature of said skin. 4. Apparatus according to claim 3 wherein said primary sensing and converting unit comprises at least one optical sensor for sensing the temperature of said skin, said at least one optical sensor receives infrared radiation emanating from an area of said skin positioned under said housing, said sensor being connected to said controller. 5. Apparatus according to claim 4 wherein the sensor receives the infra-red radiation through an optical element attached within an aperture in said housing  6. Apparatus according to claim 4 or claim 5 wherein said at least one optical sensor comprises an infra-red light sensitive photo-diode. 7. Apparatus according to claim 3 wherein said primary sensing and converting unit comprises at least one sensing temperature sensor for contacting said skin to sense the temperature of said skin, and for providing said controller with signals indicative of said temperature. 8. Apparatus according to claim 7 wherein said at least one contact temperature sensor comprises a thermistor. 9. Apparatus according to any of claims 3-8 and comprising a controller unit which controls said heat source and said source of electromagnetic radiation, for coordinating the sequence of activation of said heat source and said source of electromagnetic radiation responsive to said sensed temperature. 10. Apparatus according to claim 9 wherein the controller unit is a programmable controller. 11. Apparatus according to claim 9 or claim 10 wherein said controller unit is a controller unit having a data input capable of receiving data determining at least one treatment parameter selected from a plurality of treatment parameters for coordinating the timing and the duration of activation of any of said heat source and said source of narrow band electromagnetic radiation. 12. Apparatus according to claim 11 further including a pump attached to said housing and controlled by said controller for controllably pumping a cooler gas into said housing to displace said volume of air heated by said heat source with air having a temperature lower than the temperature of said volume of air to prevent overheating of said skin. 13. Apparatus according to claim 12 wherein said pump is activated by said controller when said skin has reached a predetermined temperature after said heat source is energized. 14. Apparatus according to claim 12 or claim 13 wherein said controller unit is a controller unit capable of determining at least one treatment parameter selected from a plurality of treatment parameters for coordinating the timing and the duration of activation of said heat source and said source of narrow band electromagnetic radiation. 15. Apparatus according to any of claims 11-14 wherein said controller unit includes a removable storage device on which said plurality of treatment parameters are stored, said removable storage device is capable of being disconnected and removed from said controller for changing the value of at least one of said plurality of treatment parameters, prior to reconnecting said storage device to said controller. 16. Apparatus according to claim 15 wherein said storage device is selected from a flash memory device, a magnetic bubble memory device, an EPROM memory device, an EEPROM memory device, an optical memory device, an opto-magnetic memory device and a magnetic memory device. 17. Apparatus according to claim 9 or claim 10 and including a cooling unit suitably attached to said housing and controlled by said controller for controllably cooling said skin, to prevent overheating of said skin. 18. Apparatus according to claim 17 wherein said cooling unit is activated by said controller when said skin has reached a predetermined temperature after said heat source is energized. 19. Apparatus according to any of claims 9-18 wherein said heat source and said source of narrow band radiation are activated substantially simultaneously. 20. Apparatus according to any of claims 9-19 wherein said source of narrow band radiation is activated by the controller when the skin temperature reaches a predetermined temperature, which predetermined temperature is above 40 degree C. 21. Apparatus according to claim 20 wherein said predetermined temperature is between about 55 degree C and 65 degree C. 22. Apparatus according to any of claims 9-21 wherein said controller interrupts said source of narrow band radiation when the target temperature reaches between about 70 degree C and about 80 degree C. 23. Apparatus according to any of claims 9-22 comprising at least one power source for energizing said heat source, said source of electromagnetic radiation and said controller. 24. Apparatus according to claim 23 wherein said at least one power source is an electrical power source. 25. Apparatus according to claim 23 or claim 24 wherein said at least one power source comprises at least one battery, at least one capacitor and an electronic control circuit. 26. Apparatus according to claim 23 or claim 24 wherein said at least one power source comprises a mains operated direct current supply, at least one capacitor and an electronic control circuit. 27. Apparatus according to any of the preceding claims wherein said cavity is a sealed cavity except for the opening to the skin. 28. Apparatus according to any of the preceding claims wherein said heat source also provides pulsed broad band light for irradiating said region of skin. 29. Apparatus according to claim 28 wherein said housing further includes a reflector for reflecting said pulsed broad band light and said narrow band electromagnetic radiation. 30. Apparatus according to claim 28 or claim 29 wherein at least part of said housing is coated by a layer of material having a high reflectivity for reflecting said pulsed broad band light and said narrow band electromagnetic radiation. 31. Apparatus according to any of he preceding claims wherein said heat source is a flash lamp or an arc discharge lamp. 32. Apparatus according to claim 31 wherein said flash lamp is a glass xenon lamp. 33. Apparatus according to claim 31 wherein said flash lamp is a quartz xenon lamp and wherein said apparatus further comprises a filter attached to said housing and disposed between said flash lamp and said opening for absorbing a pre-selected portion of said pulsed broad band light, said pre-selected portion including radiation in the ultra-violet light range which may be harmful to said skin. 34. Apparatus according to any of claims 31-33 wherein said flash lamp is disposable. 35. Apparatus according to any of the preceding claims wherein said source of narrow band electromagnetic radiation includes a flash lamp or an arc discharge lamp and a filter attached to said housing and disposed between said flash lamp and said opening for absorbing a preselected portion of said pulsed broad band light, to produce narrow band electromagnetic radiation selectively absorbed by said target tissue. 36. Apparatus according to any of the preceding claims wherein said source of narrow band electromagnetic radiation emits radiation between the wavelengths of 550 to 610 nanometers. 37. Apparatus according to any of the preceding claims wherein said housing further comprises a sealing gasket attached to said housing along the circumference of said opening for forming a sealed air cavity disposed between said skin and said heat source. 38. Apparatus according to any of the preceding claims and including an extension, said extension having a first end attachable to said opening and a second end placeable on said skin, said extension has an aperture therethrough defining an area for treating said skin. 39. Apparatus according to any of the preceding claims wherein said housing is made of a heat insulating material. 40. Apparatus according to any of the preceding claims which fits into the palm of a hand. 41. Apparatus according to any of the preceding claims wherein the source of narrow band radiation is a laser. 42. Apparatus according to any of the preceding claims wherein the apparatus is constructed to transfer from from said heated air in an amount sufficient to heat the skin to a temperature over 40 degree C. 43. Apparatus according to one of claims 41 or 42 wherein said temperature is between about 55 degree C and 65 degree C. 44. Apparatus according to claim 42 or claim 43 wherein the apparatus does not irradiate the skip when it reaches said temperature. 45. Apparatus according to any of the preceding claims the pulsable heat source is designed to heat the area subjected to the heat source to substantially the same temperature. 46. Apparatus according to claim 45 wherein the narrow band radiation is designed to selectively heat portions of the area to temperatures higher than other portions.