Microcurrent-based skin treatment and pretreatment techniques

1 . A method comprising:

pretreating a skin surface of a subject by applying a voltage or current signal to the skin surface via one or more electrodes, wherein power is output to the skin surface, and

modulating the voltage or current signal, wherein the power output is selected to enhance or increase permeability of the skin surface; and

treating the skin surface by applying an agent thereto;

wherein permeability of the skin to one or more components of the agent is enhanced or increased, responsive to the modulated power output while pretreating the skin surface, absent further voltage or current signal applied to the skin surface via the one or more electrodes; and

generating a feedback signal responsive to change in the applied voltage or current signal, wherein the change is based at least in part on sensing the voltage or current signal proximate one or more of the electrodes;

defining a response curve for modulating the power output between predetermined minimum and maximum power levels, based on the feedback signal; and

reducing the power output by lowering the response curve to or toward the predetermined minimum power level, based on a change in the feedback signal meeting or exceeding a threshold, or

increasing the power output by raising the response curve to or toward the predetermined maximum power level, based on an absence of change in the feedback signal meeting or exceeding the threshold.

2 . The method of claim 1 , further comprising:

generating the voltage or current signal as a DC, pulsed DC, microcurrent, or pulsed microcurrent waveform;

wherein the power output to the skin is charge balanced.

3 . The method of claim 1 , wherein:

the modulated power output is selected for enhanced or increased absorption, adsorption, diffusion or transmissibility of the one or more components of the agent into or through one or more of layers of the skin surface during the treatment period, as compared to said absorption, adsorption, diffusion or transmissibility absent applying the voltage or current signal to the skin surface; and

the one or more layers of the skin surface comprise a stratum corneum, outer epidermis, lower epidermis, or dermis, or wherein the one or more layers of the skin surface comprise vasculature or fibroblasts.

4 . The method of claim 1 , wherein the treatment period extends at least one to two hours after application of the voltage or current signal, or at least twelve to twenty-four hours after application of the voltage or current signal.

5 . The method of claim 1 , further comprising defining a latency period following pretreating the skin surface, wherein no further voltage or current signal is applied to the skin surface via the one or more electrodes during the latency period, wherein:

the agent is applied to the skin surface following the latency period; and

the latency period extends for at least one to two minutes following application of the voltage or current signal, at least one hour following application of the voltage or current signal, or at least six to twelve hours following application of the voltage or current signal.

6 . The method of claim 1 , further comprising generating a waveform for applying the voltage or current signal to the skin surface, wherein the waveform comprises alternating sequences of positive and negative polarity.

7 . The method of claim 6 , wherein the alternating sequences of positive and negative polarity are symmetric or aperiodic, or have randomized or pseudorandom pulse width, pulse height or period.

8 . The method of claim 1 , wherein the voltage or current signal applied to the skin surface comprises:

voltage or current pulses having amplitudes of 100 μA or less, or between 100 and 250 μA; and

voltage or current pulses having individual pulse widths between 1 and 10 ms or less, or between 10 and 100 ms.

9 . The method of claim 1 , wherein applying the voltage or current signal and modulating the power output to the skin surface are performed for a pretreatment period selected to achieve the enhanced or increased permeability of the skin upon application of the agent, and:

wherein the pretreatment period is selected for enhanced or increased absorption, adsorption, diffusion or transmissibility of the one or more components of the agent into or through one or more of layers of the skin surface during the treatment period, as compared to said absorption, adsorption, diffusion or transmissibility absent applying the voltage or current signal to the skin surface; or

wherein the pretreatment period is between one and two minutes, or between two and ten minutes.

10 . The method of claim 1 , wherein the one or more components of the agent for which the permeability is enhanced or increased comprise one or more ions or ionic or polar molecules, proteins or amino acids, or genetic material, genetic markers, allantoin, or caffeine.

11 . The method of claim 1 , further comprising applying a topical to the skin surface, wherein the topical is applied before applying the voltage or current signal, or while applying the voltage or current signal, wherein the topical comprises a conducting gel, a serum, a moisturizer, or a base component of a skin treatment product, or wherein the topical forms an electrically conducting path for the voltage or current signal between one or more of the electrodes and the skin surface.

12 . A non-transitory computer-readable medium with program code stored thereon, the program code executable on a computer processor or controller to perform a skin treatment method according to claim 1 .

13 . A method comprising:

placing at least two electrodes adjacent a skin area;

providing a microcurrent pretreatment to the skin area via a voltage or current waveform applied to the electrodes;

modulating a power output of the microcurrent pretreatment to enhance or increase permeability of the skin area for a selected treatment substance;

removing the electrodes from adjacent the skin area; and

applying the selected treatment substance to the skin area, wherein the permeability of the skin area to the selected treatment substance is enhanced or increased following removal of the electrodes;

wherein modulating the power output comprises regulating the power output between predetermined minimum and maximum power levels selected to enhance or increase the permeability of the skin surface to the selected treatment substance in the treatment phase, as compared to such a skin surface absent application of the microcurrent pretreatment in the pretreatment phase; and

generating a feedback signal responsive to change in the voltage or current waveform, wherein the change is based at least in part on sensing the voltage or current waveform proximate one or more of the electrodes;

defining a response curve for modulating the power output between the predetermined minimum and maximum power levels, based on the feedback signal; and

reducing the power output by lowering the response curve to or toward the predetermined minimum power level, based on a change in the feedback signal meeting or exceeding a threshold, or

increasing the power output by raising the response curve to or toward the predetermined maximum power level, based on an absence of change in the feedback signal meeting or exceeding the threshold.

14 . The method of claim 13 , wherein:

the waveform has charge-balanced microcurrent functional form, as defined over a period for modulating the power output of at least 100 microseconds, at least 100 milliseconds, or at least one second.

15 . A method for cosmetic treatment of a skin surface comprising a skin area according to claim 13 , and further comprising:

a pretreatment phase, comprising:

disposing the at least two electrodes adjacent the skin surface, with the skin area of the skin surface therebetween, and

providing a microcurrent pretreatment to the skin area of the skin surface via the waveform applied to the electrodes, wherein the waveform comprises one or more pulses with a same or opposite polarity; and

a treatment phase following the pretreatment phase, comprising:

applying a treatment substance to the skin area of the skin surface,

wherein permeability of the skin surface to the treatment substance is enhanced or increased responsive to the microcurrent pretreatment in the skin area between the electrodes, absent further application of the electrical waveform during the treatment phase;

wherein the waveform has a charge-balanced microcurrent functional form, and further comprising:

regulating or modulating a power output of the waveform in the pretreatment phase, wherein the power output is selected to enhance or increase the permeability of the skin surface in the skin area between the electrodes to the treatment substance in the treatment phase, and to enhance or increase user comfort during the pretreatment phase, as compared to application of the microcurrent pretreatment absent regulating or modulating the power output in the pretreatment phase.

16 . The method of claim 15 , further comprising a latency phase defined between the pretreatment phase and the treatment phase, wherein:

the latency phase extends for a period of at least five minutes; and

the treatment phase extends for a period of at least five minutes, during which the permeability of the skin surface to the treatment substance is increased or enhanced in the skin area between the electrodes, as compared to permeability of such a skin surface absent the pretreatment phase.

17 . The method of claim 15 , further comprising applying a conducting gel or fluid to the skin surface prior to or during the pretreatment phase, wherein the conducting gel or fluid is selected to form a conducting path between the electrodes and the skin area of skin surface between the electrodes, and for modulating a current density of the microcurrent pretreatment along the skin area of the skin surface between the electrodes.

18 . A method for treating the skin surface on a subject according to claim 15 , further comprising:

pretreating the skin surface of the subject by applying a voltage or current signal comprising the waveform via one or more of the electrodes, wherein power is output to the skin surface,

modulating the voltage or current signal, wherein the power output is selected to enhance or increase the permeability of the skin surface; and

treating the skin surface by applying an agent comprising the selected treatment substance thereto,

wherein permeability of the skin surface to one or more components of the agent is enhanced or increased, responsive to the modulated power output while pretreating the skin surface, absent further voltage or current signal applied to the skin surface via the one or more electrodes;

and further comprising generating the voltage or current signal as a DC, pulsed DC, microcurrent, or pulsed microcurrent waveform, wherein:

a polarity of the power output to the skin is alternated at periodic or aperiodic intervals.

19 . The method of claim 18 , wherein:

modulating the voltage or current signal comprises adjusting an amplitude of the signal such that the power output is selected for user comfort or efficacy of the enhancement or increase in permeability, or both, as compared to said power output absent modulating the voltage or current signal; or

the modulated power output is selected for the enhanced or increased permeability to include enhanced or increased absorption, adsorption, diffusion or transmissibility of the one or more components of the agent into or through one or more of layers of the skin surface during the treatment period, as compared to said absorption, adsorption, diffusion or transmissibility absent applying the voltage or current signal to the skin surface.

20 . The method of claim 18 , wherein:

the one or more layers of the skin surface comprise a stratum corneum, outer epidermis, lower epidermis, or dermis, or wherein the one or more layers of the skin surface comprise vasculature or fibroblasts, and

the treatment period extends at least one to two hours after application of the voltage or current signal, or at least twenty-four hours after application of the voltage or current signal;

and further comprising defining a latency period following pretreating the skin surface, wherein no further voltage or current signal is applied to the skin surface via the one or more electrodes during the latency period, wherein:

the agent is applied to the skin surface following the latency period, wherein the latency period extends for at least one to two minutes following application of the voltage or current signal, or for at least one to two hours following application of the voltage or current signal.

21 . The method of claim 18 , further comprising generating the waveform for applying the voltage or current signal to the skin surface, wherein the waveform comprises alternating sequences of positive and negative polarity, and:

wherein the alternating sequences of positive and negative polarity are symmetric or aperiodic, or have randomized or pseudorandom pulse width, pulse height or period; and

wherein positive and negative components of the waveform are charge balanced over a period of 0.1-0.2 s, 0.2-1.0 s, or 1.0-1.5 s.

22 . The method of claim 18 , wherein the voltage or current signal applied to the skin surface comprises:

voltage or current pulses having amplitudes of 100 μA or less, or between 100 and 250 μA; or

voltage or current pulses having individual pulse widths between 1 and 10 ms or less, or between 10 and 100 ms.

23 . The method of claim 18 , wherein applying the voltage or current signal and modulating the power output to the skin surface are performed for a pretreatment period selected to achieve the enhanced or increased permeability of the skin surface upon application of the agent, wherein:

the pretreatment period is selected for enhanced or increased absorption, adsorption, diffusion or transmissibility of the one or more components of the agent into or through one or more of layers of the skin surface during the treatment period, as compared to said absorption, adsorption, diffusion or transmissibility absent applying the voltage or current signal to the skin surface; and

the pretreatment period is between about one and two minutes or less, or between two and ten minutes.

24 . The method of claim 23 , further comprising applying a topical to the skin surface, wherein the topical is applied before applying the voltage or current signal or while applying the voltage or current signal, wherein the topical comprises a conducting gel, a serum, a moisturizer, or a base component of a skin treatment product, and wherein the topical forms an electrically conducting path for the voltage or current signal between one or more of the electrodes and the skin surface.

25 . A skin treatment system comprising:

a voltage or current source adapted to generate a voltage or current signal;

one or more electrodes adapted for applying the voltage or current signal to a skin surface of a subject, wherein power is output to the skin surface during a pretreatment phase; and

control circuitry adapted to modulate the power output to the skin surface during the pretreatment phase, wherein the power output is selected to enhance or increase permeability of the skin surface to one or more components of an agent applied to the skin surface during a treatment phase, following the pretreatment phase;

wherein the enhanced or increased permeability of the skin surface is responsive to the modulated power output in the pretreatment phase, absent further voltage or current signal applied to the skin surface via the one or more electrodes in the treatment phase; and

a voltage or current sensor configured for sensing the voltage or current signal proximate one or more of the electrodes; and

a feedback circuit configured for generating a feedback signal responsive to change in the sensed voltage or current signal, based at least in part on impedance of or through the skin surface;

wherein the control circuitry is configured to define a response curve for the power output to the skin surface; and to:

lower the response curve to or toward a predetermined minimum level, based on a change in the feedback signal, or

raise the response curve to or toward a predetermined maximum level, based on an absence of said change in the feedback signal.

26 . The skin treatment system of claim 25 , wherein the voltage or current signal comprises a microcurrent signal selected for a cosmetic treatment of the skin surface and the one or more electrodes comprise one or more pairs of electrodes having an elongated or lobed structure, wherein the voltage or current signal is applied with opposite polarity to said electrodes in each pair.

27 . The skin treatment system of claim 25 , wherein:

wherein the minimum and maximum power levels are selected to maintain user comfort, as compared to application of the voltage or current signal absent modulating the power output during the pretreatment phase; and

wherein the waveform has a charge-balanced microcurrent functional form, as defined over a period for modulating the power output of at least 100 microseconds, at least 100 milliseconds, or at least one second.

28 . The skin treatment system of claim 25 , wherein:

the agent comprises ions, ionic or polar molecules, nonionic or nonpolar molecules, proteins, amino acids, genetic material, genetic markers, allantoin, or caffeine, and

the microcurrent pretreatment is applied for a period of at least ten seconds, at least one minute, or at least two minutes; and

further comprising a latency phase defined between the pretreatment phase and the treatment phase, wherein the latency phase extends for a period of at least five minutes, at least one hour, or at least twelve hours,

wherein the treatment phase extends for a period of at least five minutes, at least one hour, or at least twelve hours, during which the permeability of the skin surface to the treatment substance is increased or enhanced, as compared to permeability of such a skin surface absent the pretreatment phase.

29 . The skin treatment system of claim 25 , wherein the agent comprises a conducting gel or fluid applied the skin surface prior to or during the pretreatment phase, and:

wherein the conducting gel or fluid is selected to form a conducting path between one or more of the electrodes and the skin surface; or

wherein the conducting gel or fluid is selected for modulating a current density of the voltage or current signal applied to an area of the skin surface between the electrodes.

30 . The skin treatment system of claim 25 , further comprising a three-terminal device having a first terminal operatively coupled to the voltage sensor, a second terminal operatively coupled to the feedback circuit, and a gate operatively coupled to the control circuitry to define the response curve based at least in part on the sensed voltage or current and the feedback signal.

31 . The method of claim 6 , wherein modulating the power output comprises controlling a pulse width, period or amplitude of the waveform based on an impedance between two of the electrodes, as determined at least in part from the feedback signal.

32 . The method of claim 1 , wherein modulating the power output is performed with a three-terminal device having a first terminal operatively coupled to a sensor configured for sensing the voltage or current waveform proximate the one or more electrodes, a second terminal operatively coupled to the feedback signal, and a gate adapted to define the response curve.

33 . The method of claim 13 , wherein the selected treatment substance comprises one or more ions, ionic or polar molecules, proteins or amino acids, or genetic material, genetic markers, allantoin, or caffeine.

34 . The method of claim 13 , wherein modulating the power output comprises controlling a pulse width, period or amplitude of the voltage or current waveform based on an impedance between two of the electrodes, as determined at least in part from the feedback signal.