Optical system for treatment of vascular lesions

Abstract

An improved optical system for treatment of disorders of the skin, especially vascular lesions, such as Port Wine Stains. The system irradiates the skin with radiation at a predetermined wavelength and cools the skin during a predetermined time interval in coordination with delivery of the radiation. The absorption of the radiation by the skin and the change in temperature of the skin is monitored by the system and the operation of the radiation delivery system is controlled to optimize treatment of the vascular lesion. The source of irradiation is an arc lamp and the cooling system delivers a cooling gas to a lens in contact with the skin. The cooling gas can be carbon dioxide, freon, or any other appropriate gas. The lens used has a high heat conductivity and may be formed of sapphire.

What is claimed is: 
     
       1. An optical system for treating vascular lesions, comprising: irradiating means for irradiating skin with electromagnetic radiation;   monitoring means coupled to said irradiating means for monitoring absorption of said radiation by said skin;   controlling means coupled to said monitoring means and said irradiating means for controlling the operation of said irradiating means to deliver a predetermined dose of radiation to said skin; and   cooling means coupled to said irradiating means for cooling the surface of said skin, said cooling means comprising: a lens having one side in contact with said skin, wherein said lens is comprised of a material that is transparent to visible light and has a high thermal conductivity; and   means for circulating a cooling .[.gas.]. .Iadd.medium .Iaddend.to contact with said lens on the side not in contact with said skin.     
     
     
       2. The system of claim 1, wherein said irradiating means comprises an arc lamp. 
     
     
       3. The system of claim 2, wherein said monitoring means comprises means for measuring the time of .[.absorption.]. .Iadd.delivery .Iaddend.of radiation. 
     
     
       4. The system of claim 2, wherein said monitoring means comprises means for measuring the reflection of radiation from the skin. 
     
     
       5. The system of claim 1, wherein said cooling .[.gas.]. .Iadd.medium .Iaddend.comprises freon. 
     
     
       6. The system of claim 1, wherein said cooling .[.gas.]. .Iadd.medium .Iaddend.comprises carbon dioxide. 
     
     
       7. The system of claim 1, wherein said lens material is sapphire. 
     
     
       8. The system of claim 1, wherein said lens material is diamond. .Iadd. 
     
     
       9.  A method of treatment with light energy comprising the steps of: providing a pulsed light output having a spectrum of frequencies continuous over at least one bandwidth from a non-laser, incoherent light source; and   directing said pulsed light output to skin, said pulsed light having controllable irradiation parameters to produce a controlled peak temperature at a variable controlled depth below a surface of said skin to selectively coagulate a target in said skin. .Iaddend..Iadd.10. A method of treating skin, comprising the steps of:   cooling a surface of skin to a predetermined temperature; and   irradiating said skin with electromagnetic radiation, at a predetermined time relative to initiation of said step of cooling said skin to produce a controlled peak temperature at a variable controlled depth. .Iaddend..Iadd.11. The method according to claim 10, said step of irradiating said skin with electromagnetic radiation further comprising the step of controlling a source of electromagnetic radiation to provide   
     
     
        pulses of electromagnetic radiation. .Iaddend..Iadd.12.  An apparatus for treating skin, comprising: pulsed cooling means operable to cool a surface of skin to a predetermined temperature; and   a source of electromagnetic radiation for irradiating said skin with electromagnetic radiation at a predetermined time relative to pulses of said pulsed cooling said skin to produce a controlled peak temperature at a variable controlled depth below a surface of said skin. .Iaddend..Iadd.13. The apparatus according to claim 12, said source of electromagnetic radiation being operable to provide pulses of   
     
     
        electromagnetic radiation. .Iaddend..Iadd.14.  The apparatus of claim 12, wherein said predetermined time is subsequent to the cooling of said skin. 
     
     
        .Iaddend..Iadd.15.  A method of treating skin, comprising the steps of: heating a portion of skin;   cooling the surface of said skin; and   controlling said heating and cooling steps of establish a controlled temperature at said skin surface and a controlled peak temperature at a   
     
     
        variable controlled depth below said surface. .Iaddend..Iadd.16.  The method according to claim 15, wherein said cooling step comprises contacting said skin with a cooled lens comprising a material with a high thermal conductivity. .Iaddend..Iadd.17. The method of claim 16, said lens comprising sapphire. .Iaddend.