Patent Publication Number: US-2010130972-A1

Title: Electrical skin treatment device and method

Description:
FIELD OF THE INVENTION 
     Our invention relates to an electrical device and method for treating problem skin areas, such as warts and other skin infections, and more particularly to a treatment device and method that applies electric sparks to the problem skin area. 
     BACKGROUND 
     Doctors have been searching for new treatments for problem skin areas, such as warts, for many years. A wart is a viral infection of the skin that creates a thickened area on the skin. Treatments for warts have included cutting and removing a section of flesh around the wart; burning the wart with lasers, heated elements, or chemicals; eroding the wart with acid; and freezing the wart, such as with liquid nitrogen. 
     Doctors also have used high powered electricity to cut and burn a patient&#39;s skin, including for the treatment of warts. Unfortunately, current treatment methods tend to be messy and/or painful, and can do permanent damage to the skin. 
     SUMMARY 
     Our invention provides an electrical device and method that uses a relatively low current and low power to treat problem skin areas, such as an infection in the skin, including but not limited to the treatment of viruses in thickened skin, such as warts. 
     More particularly, our invention provides an electrical device that includes (a) an electrode, and (b) a power source coupled to the electrode for generating an arc over a gap between a distal end of the electrode and a patient&#39;s skin when the electrode is placed in spaced proximity to a patient&#39;s skin. The power source can provide electricity to the electrode with a frequency of at least 100 kHz, an open-circuit voltage of less than 2 kV RMS , and a total power of less than 2 W, without a return electrode. 
     The device also can include one or more of the following features: 
     (a) a non-electrically-conductive spacer extending beyond the distal end of the electrode for contact with the surface of a patient&#39;s skin to define a predetermined gap between a contact surface of the spacer and the distal end of the electrode; 
     (b) an abrasive surface on the electrode to aid in removal of treated skin; 
     (c) oscillating means coupled to the electrode to oscillate the distal end of the electrode within a controlled distance along an axis between an extended position and a retracted position removed from the extended position to facilitate maintaining and re-establishing an arc between the surface of the skin and the distal end of the electrode; 
     (d) a vacuum generator to evacuate air and draw fumes away from the distal end of the electrode and the patient&#39;s skin; 
     (e) an electrode having a length dimension, and the distal end of the electrode is movable relative to a central longitudinal axis; 
     (f) an electrode that is movable relative to the longitudinal axis to allow the distal end of the electrode to sweep through a larger area; 
     (g) an electrode where a portion at a distal end of the electrode is offset from a longitudinal axis of another portion of the electrode; 
     (h) a supply of gas or liquid and an outlet port to direct the fluid toward a distal end of the electrode; 
     (i) the device in combination with a protective non-electrically-conductive material for placement adjacent a treatment area to protect healthy skin from the electrical arc; and 
     (j) an electrode that includes an array of electrodes connected to the voltage generator, and a voltage distributor for applying a voltage to more than one electrode in the array. 
     Our invention also provides a method for treating problem skin areas that includes the following steps: (a) generating a voltage and providing that voltage to a distal end of an electrode, and (b) positioning the electrode in proximity to a patient&#39;s skin to form an arcable gap between the electrode and the skin to produce an electric spark that arcs across the gap with sufficient intensity to treat the problem skin area but insufficient to cause significant damage to normal surrounding tissue. 
     The method can further include one or more of the following steps: 
     (a) generating a high frequency (at least 100 kHz) voltage (less than 2 kV RMS  open circuit) with less than 2 W of power to a monopolar electrode; 
     (b) providing a voltage such that in the moving step the electric spark arcs across the gap with a substantially constant current of less than 30 mA RMS  between the electrode and the skin; 
     (c) contacting the surface of a patient&#39;s skin near a problem skin area with a non-electrically-conductive element that spaces the patient&#39;s skin from a distal end of an electrode to form a gap between a contact surface of the non-electrically conductive element and the distal end of the electrode; 
     (d) generating a vacuum near the patient&#39;s skin to evacuate air and draw fumes away from the patient&#39;s skin; and 
     (e) measuring the size of a treatment area of a patient&#39;s skin, and selecting a plurality of electrodes to distribute voltage to based on the measured size of the treatment area. 
     The foregoing and other features of the invention are more fully described and particularly pointed out in the claims. The following description and annexed drawings set forth in detail several illustrative embodiments, these embodiments being indicative of but a few of the various ways in which the principles of the invention may be employed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of an electrical device provided by our invention. 
         FIG. 2  is a perspective view of an exemplary electrical device provided by our invention. 
         FIG. 3  is a schematic elevation view of the electrical device of  FIG. 2   
         FIG. 4  is a partial view of a distal end of an electrical device provided by our invention. 
         FIG. 5  is a partial view of a distal end of another electrical device provided by our invention. 
         FIG. 6  is a partial of a distal end of another electrical device provided by our invention. 
         FIG. 7  is a perspective view of another electrical device provided by our invention. 
         FIG. 8  is a perspective view of an electrical device similar to the device shown in  FIG. 7 . 
         FIG. 9  is a perspective view of an electrical device similar to the device shown in  FIG. 7 . 
         FIG. 10  is a partial of a distal end of another electrical device provided by our invention. 
         FIGS. 11 and 12  are partial end views of another electrical device provided by our invention that illustrate movement of one element. 
         FIG. 13  is a partial view of an electrical device in combination with a protective sheet provided by our invention. 
         FIG. 14  is a schematic cross-sectional view of an exemplary removable electrode assembly unit mountable to a distal end of another electrical device provided by our invention. 
     
    
    
     DETAILED DESCRIPTION 
     Our invention provides an electrical device and method that uses a relatively low current and low power to treat problem skin areas. Problem skin areas can be caused by, among other things, an infection in the skin, including but not limited to viruses, such as the viruses that cause warts. We have found that in proper use a device employing our invention can effectively and nearly painlessly treat some problem skin areas, and is particularly effective in treating warts, a treatment that has been sought for many years without success. 
     Turning now to the drawings, and initially  FIG. 1 , our invention provides an electrical device  20  that includes at its core an electrode  22  and a power source  24  coupled to the electrode  22  for generating an arc over a gap G ( FIG. 3 ) between a distal end  26  of the electrode  22  and a patient&#39;s skin S ( FIG. 3 ) when the electrode  22  is placed in spaced proximity to a patient&#39;s skin. The power source  24  preferably, although not necessarily, is contained in a housing  28  from which the electrode  22  extends. The electrode  22  has a length dimension and a longitudinal axis generally along its length. The electrode  22  can be a disposable component, or it can be removable for cleaning and sterilization, or replaceable with a different type of electrode. Several different types of electrodes are described below, but other variations in shape and materials are envisioned. The electrode  22  provides an electrically-conductive path for the electricity provided by the power source  24  and typically has a pointed distal end  26  at which an electrical charge can accumulate to create a spark that will arc across the gap. 
     The power source  24  generally includes a controller  30  with a processor  32  and a memory  34  coupled to the processor  32  for storing any programming required for generating, monitoring, and/or regulating the necessary electrical voltage provided to the electrode  22 , and a supply of electricity  36  controlled by the controller  30 . The supply of electricity can include any source of electricity, including an electricity generator, or a power cord for connection to an electrical outlet, and a suitable transformer (not shown). The power source  24  is preferably self-contained within the device  20 , if not within a common insulated housing  28 , so that it can be portable and used unencumbered by a power cord. For example, the supply of electricity  36  can include a single-use or rechargeable battery, a fuel cell, or the like. The power source  24  also can include an input device  40 , such as an on/off switch, and an output device  42 , such as a status-indicator light, for providing information to and from the controller  30 . 
     An exemplary power source  24 , which also could be referred to or include a voltage generator or voltage-generating means, has its output terminal  41  connected to the electrode  22  and provides it with an open circuit voltage of less than 2 kilovolts RMS (2 kV RMS ), at a frequency of at least one hundred kilohertz (100 kHz), and a total power of less than two watts (2 W). The other output terminal  43  of the power source  24  is connected to a small metallic plate  45  which is contained within the common insulated housing  28 . This metallic plate  45  provides capacitive coupling between the power source  24  and the body of the operator of the device. In turn, the operator is capacitively coupled to ground. Since the patient is also capacitively coupled to ground, a complete circuit is available without the need for a return electrode attached to the patient. During arcing, the power source  24  provides an open circuit current of less than thirty milliamps RMS (30 mA RMS ) between a distal end  26  of the electrode  22  and the patient&#39;s skin. These features allow our device  20  to operate with minimal or no pain or damage to normal healthy skin. The voltage and power are much lower than in the electrical devices used for electrosurgery for cutting and cauterizing, which can be both messy and painful. The lower power, however, also means that our device probably is not suitable for the cutting and cauterizing operations traditionally associated with electrosurgical procedures. 
     These basic components can be used to build a simple electrical device, an example of which is shown in  FIGS. 2 and 3 . This electrical device  44  includes an electrode  22  extending from a housing  28 , and a power source  24  coupled to the electrode  22  for generating an arc over a gap G when the distal end  26  of the electrode  22  is placed in spaced proximity to a patient&#39;s skin S. The power source  24  includes a controller  30 , a supply of electricity  36 , an on/off switch input device  40  and a status-indicator light output device  42 . When an arc is generated, it tends to prefer areas of increased resistance, such as thicker, drier skin, including a callous or a wart, for example, rather than normal skin tissue. The doctor or other operator can move the distal end of the electrode over the problem skin area to be treated. The distal end  26  or tip of the electrode  22  can be brought closer to or into contact with the skin to initiate an arc and moved further away from the skin during normal operation to provide a larger gap for treatment with the arcing electrical spark. 
     Other features that can be provided in the device  20  are shown in  FIG. 1  and include one or more of a motive device  50  or motive means coupled to the electrode  22 , a fluid source  52 , and a vacuum generator  54 . The motive device  50  enables movement of the distal end  26  of the electrode  22  relative to a central longitudinal axis. To provide this movement, the motive device  50  includes a motor  56  controlled by the controller  30  and an associated linkage and/or gearing  58  coupling the motor  56  to the electrode  22 . The motive device  50  can move the electrode  22  in any direction, along its axis or another axis, transverse its axis, rotated about an axis, or a combination thereof. 
     One reason for moving the electrode  22  is to help to initiate and/or maintain the arc. For example, the electrode  22  can be controllably oscillated along its length. To that end the motive device  50  includes oscillating means coupled to the electrode  22  to oscillate the distal end  26  of the electrode within a controlled distance along an axis between an extended position and a retracted position removed from the extended position to facilitate maintaining or reestablishing an arc between the surface of the skin and the distal end  26  of the electrode. The oscillating means includes the controller  30  or a separate control mechanism to control the motive device  50  to control movement of the electrode  22  to the extended position for a first time to make it easier for a spark to jump the gap and initiate an arc and to the retracted position for a second time that is longer than the first time to apply the arc for treatment of a problem skin area. The oscillating means also can include means for monitoring the arc voltage to control the position of the distal end  26  of the electrode. This monitoring function can be incorporated into the device controller  30 . By monitoring the voltage, the electrode  22  can be moved automatically to the extended position to re-strike the arc when a voltage drop indicates that the arc has been extinguished. 
     To apply the electric arc treatment provided by the device to a larger area without the doctor or other operator moving the device  20 , the motive device  50  also can move the electrode  22  so that the distal end  26  of the electrode automatically moves through a path or pattern that covers a desired area. The pattern can be circular, linear, zig-zag, or random, for example. 
     One way to move the electrode  22  in a straight line is to provide a linear slide to which the electrode is affixed for movement in one or more directions transverse the longitudinal axis. When coupled with a device to rotate the electrode  22 , a large variety of patterns can be created by moving the electrode linearly and rotatably relative to the axis of rotation. 
     As shown in  FIG. 4 , rotating the distal end  26  of the electrode  22  about a longitudinal axis of rotation  60  from which at least a portion of the distal end of the electrode is displaced or offset, without imparting linear motion, can create a circular pattern. The diameter of the circle through which the distal end of the electrode moves can be varied in several ways. 
     One way to change the diameter is to provide a biasing member  62  coupled to the electrode  22  to bias the electrode toward a central position. This arrangement allows the electrode  22  to move radially outward against the bias force of the biasing member  62  as the electrode rotates. This type of electrode  22  can increase the diameter of the circular pattern through which the distal end  26  moves by increasing the rotational speed. Centrifugal force counters the biasing force to move the distal end  26  outward as a function of the speed. As the rotational speed decreases, the biasing member  62  will urge the electrode  22  back toward a central position and decrease the diameter of the circular path traveled by the distal end  26  of the electrode. 
     Another way to achieve a similar result is to use an electrode  22  that is flexible transverse its length dimension so that the distal end  26  of the electrode moves radially outward as it rotates, as shown in  FIG. 6 . 
     Another way to change the diameter is by offsetting a portion  64  of the electrode  22  toward a distal end  26  relative to another portion  66  of the electrode, and relative to the axis  60  about which the electrode  22  rotates, as shown in  FIG. 5 . Alternatively, the electrode can be curved, so that the distal end of the electrode is offset from an axis of a proximal portion of the electrode. 
     To maintain a constant distance, or spark gap, between the distal end  26  of the electrode  22  and the problem area of a patient&#39;s skin, the electrode  22  can have a variable length dimension which is increased with increasing rotational speed. The electrode can have telescopic sections or can telescope relative to the housing  28  of the device  20  to extend more or less distance from the housing. 
     Another way to treat a larger area is to use multiple electrodes, as shown in  FIGS. 7-9 . In this device  67 , the electrode includes an array  68  of electrodes  22  connected to the voltage generator or power source  24 , and a voltage distributor  70  for applying a voltage to more than one electrode in the array. The voltage distributor  70  is capable of distributing voltage to multiple electrodes simultaneously or sequentially. The voltage distributor  70  also is capable of distributing voltage to fewer than all of the electrodes. 
     Returning to  FIG. 1 , in addition to or in place of the motive device  50 , the device  20  can include the fluid source  52  mentioned above. The fluid source  52  includes supply of fluid  76 , a fluid pump  78 , and an outlet port  80  to direct the fluid toward the distal end  26  of the electrode  22 . The supply of fluid  76  includes a reservoir of fluid, such as a liquid and/or gas. The outlet port  80  can be provided by an outlet nozzle extending from the housing  28  to direct fluid toward the distal end  26  of the electrode  22  to facilitate the formation or maintenance of the arc, or provide an additional treatment for the problem skin area. 
     The other added feature in  FIG. 1  is the vacuum generator  54  mentioned above. The vacuum generator  54  includes an air pump  82 , fan, or other device to create a negative pressure to evacuate air and draw fumes away from the distal end  26  of the electrode  22  and the patient&#39;s skin. The illustrated vacuum generator  54  also includes an inlet port  84 , an example of which is shown in  FIG. 8 , and a filter  86 , such as charcoal filter media, or another filter media, to filter the fumes in the evacuated air drawn away from the distal end  26  of the electrode. The filter  86  can be replaceable, and can capture particulates, liquids, and/or gases in the evacuated air. The filter thus can absorb odors. The vacuum generator  54  also can be used to recover the fluid from the fluid source  52 . The filter can be combined with an electrode so that both the filter and the electrode can be replaced as a unit. One way that this can be accomplished is by incorporating a distal portion of the housing  28  that facilitates interfacing with a receptacle to couple the unit to other components of the device. The device  20  also can include means for introducing a scent into the exhaust air from the air pump  82 . For example, the evacuated filtered air can be passed through or past a scented pad  88  or a gel, for example, as it is exhausted from the housing  28  via an exhaust port  90 . 
     In addition to or as an alternative to these features, we also contemplate that the electrode  22  can be removable, such as for cleaning, sterilizing, or replacement. Or as shown in  FIG. 10 , the electrode  22  can have an abrasive, filed, or otherwise roughened surface  92  mounted to a side of the electrode or integral with the electrode to aid in removal of treated skin where desired. 
     Another feature that can be provided with this device is a non-electrically-conductive spacer  100 , shown in  FIGS. 11 and 12 , for example, that extends beyond the distal end  26  of the electrode  22  for contact with the surface of a patient&#39;s skin to define a predetermined gap G between a contact surface  102  of the spacer  100  and the distal end  26  of the electrode. Another exemplary spacer  104  is shown in  FIG. 9 . 
     The spacer can be removable and disposable, to ensure sterility between patients, using screws or a snap-fit to hold the spacer on the housing  28 , or it can be permanently mounted but movable, for example by being pivotable away from the electrode  22 . Being able to move the spacer is advantageous in that moving the spacer out of the way allows the operator to move the distal end  26  of the electrode to contact the skin and initiate an arc, and then use the spacer to define a predetermined gap over which the arc can travel. This predetermined gap can help the operator maintain a consistent arc. 
     The illustrated spacer  100  includes a movable element  106  that is movable between an extended position to allow the electrode  22  to extend to the contact surface  102  to initiate the electric spark, as shown in  FIG. 11 , and a retracted position removed from the extended position to space the electrode  22  from the contact surface  102  a distance that provides electrical arcing, as shown in  FIG. 12 . The illustrated spacer  100  also includes a biasing element  110 , such as a spring, that biases the movable element  106  in a distal direction to the extended position. 
     The spacer is relatively open, or alternatively clear, to maintain visual contact with the distal end  26  of the electrode  22  and to provide visual confirmation of the existence of an electric arc. The transparency required is only such that the doctor or other operator can determine whether the arcing spark is present or has been extinguished. Accordingly, a transparent spacer is not always necessary and a translucent spacer may be suitable for some applications. 
     We also contemplate using the device we have described in combination with a protective non-electrically-conductive material, in this case a sheet material  112  for placement adjacent a treatment area to protect healthy skin from the electrical arc. The non-electrically-conductive sheet  112  shown in  FIG. 13  has an opening  114  for access to the treatment area. The sheet material  112  preferably at least partially surrounds the treatment area. The non-electrically-conductive sheet material  112  may also have a thickness sufficient to space the electrode  22  a distance to provide an optimal electrical arc. The electrical resistance of this material  112  also can help to focus the electrical discharge on the treatment area. The material  112  might have a higher resistance than the treatment area, for example. The sheet material  112  also can protect the treated area after treatment, when the treated area might be more sensitive. This combination can be considered a kit, including both the electrical device  20  and the non-electrically-conductive material, which also can function as a bandage. 
       FIG. 14  shows an exemplary removable electrode assembly unit  120  that includes an electrode  122  having a threaded base, a filter  86  and a housing or shroud  126  that includes one or more passages  124  that define an inlet port  84  for drawing air from around the electrode through the filter  86 . The shroud  126  also serves as a spacer to space a distal tip  128  of the electrode  122  relative to a contact surface  130  at a distal end of the shroud  126 . Instead of or in addition to the threaded connection shown, the electrode  122  and/or the shroud  126  can be secured to a distal end of the housing  28  ( FIG. 1 ), and in fact the shroud  126  can define a distal portion of the housing  28 . The shroud  126  and/or the electrode  122  can be secured in place for use by a threaded, snap, or press-fit connection that allows for the removal and replacement of the electrode assembly  120  as a unit. 
     Our invention also provides a method for treating problem skin areas that includes the following steps: (a) generating a voltage and providing that voltage to a distal end of an electrode; and (b) positioning the electrode in proximity to a patient&#39;s skin to form an arcable gap between the electrode and the skin to produce an electric spark that arcs across the gap with sufficient intensity to treat the problem skin area but insufficient to cause significant damage to normal surrounding tissue. The generating step includes generating a high frequency (at least 100 kHz) voltage (less than 2 kV RMS  open circuit) with less than 2 W of power to a monopolar electrode. The generating step also can include providing a voltage such that in the moving step the electric spark arcs across the gap with a substantially constant open circuit current of less than thirty milliamps RMS (30 mA RMS ) between the electrode and the skin. 
     When employing a spacer, the positioning step includes contacting the surface of a patient&#39;s skin near a problem skin area with a non-electrically-conductive element that spaces the patient&#39;s skin from a distal end of an electrode to form a gap between a contact surface of the non-electrically conductive element and the distal end of the electrode. 
     When the device includes a vacuum source, the method can include the step of generating a vacuum near the patient&#39;s skin to evacuate air and draw fumes away from the patient&#39;s skin, and/or filtering fumes from the evacuated air drawn from the patient&#39;s skin. 
     As mentioned above, in the multiple-electrode embodiment of the device, fewer than all of the electrodes can be energized. Accordingly, the method can include the steps of: (a) measuring the size of a treatment area of a patient&#39;s skin; and (b) selecting a plurality of electrodes to distribute voltage to based on the measured size of the treatment area. In this way, the problem skin area can be treated all at once or in less time than if a single electrode had to be moved over the same area. 
     Although the invention has been shown and described with respect to certain embodiments, equivalent alterations and modifications will occur to others skilled in the art upon reading and understanding this specification and the annexed drawings. In particular regard to the various functions performed by the above described integers (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such integers are intended to correspond, unless otherwise indicated, to any integer which performs the specified function of the described integer (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment of the invention.