Method and apparatus for treatment of skin using rf and ultrasound energies

Abstract

A system and method for treating skin. The System comprises one or more ultrasound transducers and one or more pairs of RF electrodes. The ultrasound transducers are adapted to focus ultrasound energy at one or more focal volumes in the skin. The RF electrodes are adapted to deliver RF energy to the one or more focal volumes. The method comprises heating the skin to a first temperature at one or more focal volumes in the skin by focusing ultrasound energy at the one or more focal volumes. The focal regions are then heated to a second temperature, the second temperature being higher than the first temperature, by generating an RF current in a region of the skin containing the focal regions.

1 .- 38 . (canceled) 
   
   
       39 . A method for treating skin including:
 applying to skin ultrasound radiation and focusing it at one or more focal volumes in the dermis and heating the focal volumes to raise the electrical conductivity of the volumes;   preventing substantial heat flow from the focal volumes in course of the treatment by keeping ultrasound application time below 10 sec;   applying to skin RF energy and generating an RF current further heating the one or more focal volumes with raised electrical conductivity; and   wherein the generated by RF energy current flows through one or more focal volumes with raised electrical conductivity and the electric field generated by the RF current matches in space the focal volumes produced by the ultrasound radiation.   
   
   
       40 . The method according to  claim 39  wherein the RF current matches in time the application of RF energy such that application of the RF energy immediately follows application of the ultrasound radiation or may persist during at least a time ultrasound radiation is applied. 
   
   
       41 . The method according to  claim 39  wherein the RF current has a frequency between 100 KHz and 100 MHz and the ultrasound energy has a frequency between 500 KHz and 50 MHz. 
   
   
       42 . The method according to  claim 39  wherein the RF energy is applied in a train of one or more pulses. 
   
   
       43 . The method according to  claim 39  further including cooling the skin surface. 
   
   
       44 . The method according to  claim 39  wherein one or more of the focal volumes are located between 0.2 mm and 5 mm below the skin surface. 
   
   
       45 . The method according to  claim 44  wherein one or more of the focal volumes are located between 0.2 mm to 2 mm below the skin surface. 
   
   
       46 . The method according to  claim 39  wherein a lateral width of one or more of the focal volumes is between 0.05 mm to 1 mm. 
   
   
       47 . The method according to  claim 46  wherein the lateral width of one or more of the focal volumes is between 0.1 mm to 0.3 mm. 
   
   
       48 . The method according to  claim 39  wherein a lateral spacing between focal volumes is between 0.3 mm to 3 mm. 
   
   
       49 . The method according to  claim 48  wherein the lateral spacing between focal volumes is between 0.5 mm to 1 mm. 
   
   
       50 . The method according to  claim 39  wherein a length of the focal volumes between the RF electrodes is between 1 mm to 20 mm. 
   
   
       51 . The method according to  claim 50  wherein the length of the focal volumes between the RF electrodes is between 3 mm to 10 mm. 
   
   
       52 . A method for treating skin including:
 applying to skin ultrasound radiation and focusing it at one or more focal volumes in the dermis and heating the focal volumes to a first temperature above the temperature of dermis volumes surrounding the focal volumes;   preventing substantial heat flow from the focal volumes in course of the treatment by keeping ultrasound application time below 10 sec;   heating the one or more focal volumes to a second temperature, the second temperature being higher than the first temperature, by generating an RF current in the dermis containing the one or more focal volumes.   
   
   
       53 . The method according to  claim 52  wherein the first temperature is between 44 degree C. to 90 degree C. 
   
   
       54 . The method according to  claim 52  wherein the ultrasound energy is focused on the one or more focal volumes for an amount of time between 10 msec and 10 sec. 
   
   
       55 . The method according to  claim 52  wherein the RF current matches in time the application of RF energy such that application of the RF energy immediately follows application of the ultrasound radiation or may persist during at least a time ultrasound radiation is applied. 
   
   
       56 . The method according to  claim 52  wherein the temperature generated by RF energy current flows through one or more focal volumes with raised electrical conductivity and the electric field generated by the RF current matches in space the focal volumes produced by the ultrasound radiation. 
   
   
       57 . A method for skin treatment, the method including:
 applying to the skin to be treated a system including:   (i) at least one ultrasound transducer configured to focus ultrasound energy at one or more focal volumes in the dermis and heat the volumes such that their electrical conductivity is increased; and   (ii) at least one pair of RF electrodes configured to deliver RF energy to the focal volume with increased electric conductivity; and   wherein the ultrasound heated volumes with raised electrical conductivity form a guided current path through which the RF energy induced current flows further heating the volumes.   
   
   
       58 . A system for treating skin, the system including:
 an applicator including one or more pair of RF electrodes and one or more ultrasound transducers with each transducer located between a respective pair of RF electrodes;   a processor controlling at least a power supply operative to drive the ultrasound transducers and at least one power supply operative to drive the RF electrodes, and   wherein each ultrasound transducer produces a focal volume covered by the electric field generated by the respective RF electrodes; and   wherein the power supply drives the RF electrodes immediately following application of ultrasound energy to the focal volumes.   
   
   
       59 . The system according to  claim 58  further including an input device for inputting one or more parameters of the treatment of the processor. 
   
   
       60 . The system according to  claim 59  wherein the one or more parameters are selected from the group consisting of a frequency of RF voltage, an intensity of RF voltage, a duration of RF energy, an intensity of ultrasound region, and a depth below the skin surface of the focal regions. 
   
   
       61 . The system according to  claim 58  wherein RF energy is between 100 KHz and 100 MHz and the ultrasound energy has a frequency between 500 KHz and 50 MHz. 
   
   
       62 . The system according to  claim 58  wherein the processor is configured to apply RF energy in a train of one or more pulses. 
   
   
       63 . The system according to  claim 58  wherein the processor is configured to apply an RF voltage to the RF electrodes for an amount of time between 1 sec and 10 sec and to activate the ultrasound transducer for an amount of time between 1 sec and 10 sec. 
   
   
       64 . The system according to  claim 58  wherein the ultrasound transducers are configured to focus ultrasound energy to one or more focal volumes located in a dermis layer of the skin. 
   
   
       65 . The system according to  claim 58  further including a cooling system cooling the skin surface. 
   
   
       66 . The system according to  claim 58  including an applicator configured to be applied to the skin surface, the applicator containing the ultrasound transducer and the RF electrodes. 
   
   
       67 . The system according to  claim 58  wherein at least one pair of RF electrodes and at least one ultrasound transducer are contained in an applicator in which at least one ultrasound transducer is located between a pair of RF electrodes. 
   
   
       68 . The system according to  claim 58  wherein one or more of the focal volumes are located between 0.2 mm and 5 mm below the skin surface. 
   
   
       69 . The system according to  claim 68  wherein one or more of the focal volumes are located between 0.2 mm to 2 mm below the skin surface. 
   
   
       70 . The system according to  claim 58  wherein a lateral width of one or more of the focal volumes is between 0.05 mm to 1 mm. 
   
   
       71 . The system according to  claim 70  wherein the lateral width of one or more of the focal volumes is between 0.1 mm to 0.3 mm. 
   
   
       72 . The system according to  claim 58  wherein a lateral spacing between focal volumes is between 0.3 mm to 3 mm. 
   
   
       73 . The system according to  claim 72  wherein the lateral spacing between focal volumes is between 0.5 mm to 1 mm. 
   
   
       74 . The system according to  claim 58  wherein a length of the focal volumes between the RF electrodes is between 1 mm to 20 mm. 
   
   
       75 . The system according to  claim 74  wherein the length of the focal volumes between the RF electrodes is between 3 mm to 10 mm. 
   
   
       76 . A system for skin treatment, the system including:
 at least one ultrasound transducer configured to focus ultrasound energy into at least one focal volume in the dermis and operative to raise the electrical conductivity of the volume;   at least one pair of RF electrodes configured to deliver RF energy into the volumes with raised electrical conductivity; and   wherein an RF current generated by the RF energy flows between the pair of RF electrodes through the focal volumes with raised electrical conductivity.   
   
   
       77 . A system for skin treatment, the system including:
 an applicator including one or more pair of RF electrodes and one or more ultrasound transducers with each transducer located between a respective pair of RF electrodes;   a power supply operative to drive the ultrasound transducers and at least one power supply operative to drive the RF electrodes, and   wherein each ultrasound transducer produces a focal volume matched in space with the electric field generated by the respective RF electrodes; and   wherein the power supply matches in time application of RF energy and ultrasound energy to focal volumes such that it drives the RF electrodes immediately following application of ultrasound energy to the focal volumes.   
   
   
       78 . An applicator for skin treatment including one or more pair of RF electrodes and one or more ultrasound transducers with each transducer located between a respective pair of RF electrodes the applicator characterized in that electric field generated by the RF electrode covers focal volume of the respective ultrasound transducer and application of the RF energy to the focal volumes immediately follows the application of ultrasound.