Abstract:
A CFS system includes self-adhesive, disposable pads. Each pad is combined with a sealed, cleanable battery/controller pod and then placed on the body where needed. The battery/controller pod preferably has wireless capability, such as Bluetooth® capability. The patient can download an application to a smartphone or similar mobile device to control the pods.

Description:
REFERENCE TO RELATED APPLICATIONS  
       [0001]    The present application claims the benefit of U.S. Provisional Patent Application No. 61/767,509, filed Feb. 21, 2013. Related subject matter is disclosed in U.S. Patent Application Publication No. 2010/0274327 A1 and in U.S. Pat. Nos. 8,086,322 and 8,386,005. The disclosures of all of the above applications and patents are hereby incorporated by reference in their entireties into the present disclosure. 
     
    
     FIELD OF THE INVENTION  
       [0002]    The present invention is directed to cutaneous field stimulation and more particularly to such stimulation with disposable and rechargeable components. 
       DESCRIPTION OF RELATED ART  
       [0003]    Electroanalgesic therapies are known nonpharmacologic alternatives to conventional analgesic drugs for the management of acute and chronic pain. For example, percutaneous electrical nerve stimulation (PENS) is a known form of electroanalgesic therapy typically used for the treatment of intractable pain associated with chronic low back pain syndrome by stimulating the spinal cord (SCS) using electrodes implanted percutaneously into the epidural space as a trial before a more permanent total implantation of an SCS System. The term PENS has also been used to describe a technique for inserting 32-gauge acupuncture needles into soft tissues or muscles to electrically stimulate peripheral nerve fibers in the sclerotomal, myotomal, or dermatomal distribution corresponding to a patient&#39;s pain symptoms. Medical devices having arrays of percutaneous electrodes that utilize microstructure needles, which are less invasive than deeper-penetrating acupuncture needles, have also been used for delivering PENS. The microstructure needles provide sufficient penetration to overcome the electrical impedance of the skin tissue for effectively recruiting sensory fibers. 
         [0004]    As the understanding of the topographical organization of nociceptive systems becomes more detailed, the target location of the stimulation, the percutaneous electrodes&#39; depth of penetration, and the current amplitude become more exacting. Percutaneous neuromodulation therapy (PNT) and cutaneous field stimulation (CFS) are specific forms of PENS that have been developed using that understanding. PNT is used for the treatment of cervical and lumbar pain and utilizes longer, acupuncture-type needles having a depth of penetration into the skin tissue of up to 3 cm. CFS is used more generally to treat pain and itch and utilizes an array of microstructure needles introduced close to the nerve endings in the skin. Because of the stringent requirements established for needle electrodes by the Food and Drug Administration (FDA) regarding the packaging, sterilization, reuse, and disposal of such electrodes, treatments utilizing such electrodes have generally been administered under the supervision of a physician (e.g., in a doctor&#39;s office or a clinic). 
         [0005]    CFS is used to assist in the management of chronic nociceptive and neuropathic pain based on the understanding that specific types of sensory nerves that are linked to diminishing the perception of pain can be activated by low amplitude, long duration electrical stimulation if electrodes having sharp tips (i.e., microstructure needles) are introduced close to the nerve endings in the skin. CFS treatment also influences specific active components necessary for perceiving itch by inducing long lasting inhibitory mechanisms in central pathways and by actually normalizing the number of epidermal sensory fibers in itchy skin. Accordingly, CFS also provides an alternative to known treatments for localized itch. 
         [0006]    The sensory receptors stimulated by CFS are axons within the skin tissue known as nociceptors, specifically Aδ and C nerve fibers. The stimulation of Aδ and C nerve fibers, although effective in diminishing the perceptions of both pain and itch, can be a relatively uncomfortable treatment because a prickling and/or burning sensation is perceived from the stimulation of the Aδ and C nerve fibers, which can be uncomfortable and painful. Because the aversiveness of Aδ and C nerve fiber stimulation can be masked by Aβ fiber stimulation, it would be a considerable advantage to combine Aδ fiber stimulation (e.g., transcutaneous electrical nerve stimulation (TENS)) and Aδ and C fiber stimulation (e.g., CFS) in the same equipment. Accordingly, there is a need for a method and device that combines Aβ fiber stimulation and Aδ and C fiber stimulation in one treatment. Moreover, there is a need for a method and device that combines TENS and CFS in one treatment. 
         [0007]    Cutaneous Field Stimulation (CFS) is a technique for relieving itch and pain that allows topographically restricted and tolerable electrical stimulation of thin (Aδ and C) cutaneous fibers but is not well suited for the stimulation of Aβ fibers. CFS uses a flexible plate with multi-array needle-like electrodes regularly fixed at 2-cm intervals. Each electrode is surrounded by an elevated “stop-device” about 2.0 mm in diameter that protrudes 2.0 mm from the plate. The electrode tip usually protrudes 0.3 mm to 0.4 mm from the stop-device. When gently pressing the electrode plate against the skin, the electrode tips are introduced close to the receptors in the epidermis and the superficial part of dermis. Since the electrodes traverse the electrically isolating horny layer of the epidermis and the current density is high near the sharp electrode tips, the voltage and current required for stimulating cutaneous nerve fibers are small, typically less than 50 V and up to 2 mA, respectively. As the current density decreases rapidly with distance, localized stimulation is achieved. The electrodes are stimulated consecutively with a constant current stimulator, each electrode with a frequency of 1-10 Hz (pulse duration 1.0 ms) and treatment duration of 5-45 min. In its original embodiment, a self-adhesive surface (TENS) electrode served as anode and was usually placed about 5-30 cm away from the needle electrode plate. 
         [0008]    Recent improvements in CFS are taught, e.g., in U.S. Pat. No. 8,086,322. However, it would be helpful to provide a CFS system that is less expensive and more easily used than present systems. 
         [0009]    CFS works best on pain or itch that is focused in one main area. Therefore, one of the challenges of using CFS for itch or pain that is not focused in one particular area is the distribution of the signal. CFS is most effective when placed directly over the area of pain or itch. Therefore, pain or itch that is distributed over multiple areas requires repeated use of the stimulator serially in each zone of pain or itch. Having a system that would allow simultaneous stimulation of multiple sites with an easy to use interface would be advantageous. 
       SUMMARY OF THE INVENTION 
       [0010]    It is therefore an object of the invention, in at least some embodiments, to provide a system using less expensive pads. 
         [0011]    It is another object of the invention, in at least some embodiments, to provide such a system that is easier and more convenient for the patient to use. 
         [0012]    It is still another object of the invention, in at least some embodiments, to provide such a system that uses, as its controller, a device that the patient will likely already own, such as a smartphone. 
         [0013]    To achieve the above and other objects, the present invention, in at least some embodiments, is directed to a CFS system having self-adhesive, disposable pads. Each pad is combined with a sealed, cleanable battery/controller pod and then placed on the body where needed. 
         [0014]    The battery/controller pod preferably has wireless capability, such as Bluetooth® capability. The patient can download an application to a smartphone or similar mobile device (e.g., iPhone, iPad, or Android smartphone). The application guides the patient in the placement of the pads and then controls the smartphone or other mobile device to connect with the battery/controller pods wirelessly and to act as a central controller for the battery/controller pods. The use of that application allows both easy upgradability and a user-friendly graphical user interface and also makes use of a device that the patient likely already has and with which the patient is familiar. 
         [0015]    The patient is also provided with an inductive charger for the battery/controller pods. The inductive charger can also have cleaning capability. Once the treatment is over, the patient discards the pads and places the pods into the charger. 
         [0016]    A CFS system that has multiple channels with a fewer number of needle like (NL) electrodes per electrode plate (4 to 6 instead of 14 to 16) could be tailored to more effectively treat each zone of pain or itch by titrating the level of stimulation or amplitude for each channel or zone. The size of the treatment zone could also be increased or decreased by adding multiple disposable electrode plates to match the size of the pain or itch zone. The level of stimulation or amplitude of each electrode plate could be individually adjusted and tuned to provide the optimal amount needed at each zone. Using a remote controller (e.g., a smartphone) to adjust the output and parameters of each zone and connecting the controller with each of the electrode plates using Bluetooth or other wireless technology would greatly increase the convenience and ease of use of the CFS system. This type of CFS system would provide a more effective and easier to use treatment of pain and itch due to its scalability, convenience and adjustability. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    A preferred embodiment of the present invention will be set forth in detail with reference to the drawings, in which: 
           [0018]      FIG. 1  is a drawing showing the configuration of a pad; 
           [0019]      FIG. 2  is a drawing showing a retail package in which the pads are sold to the patient; 
           [0020]      FIG. 3  is a drawing showing the way in which the pad and the pod are combined for use; 
           [0021]      FIG. 4  is a schematic diagram showing the circuitry in the pod of  FIG. 3 ; 
           [0022]      FIG. 5  is a drawing showing the way in which the pods are placed into the charger after use; 
           [0023]      FIG. 6  is a drawing showing the smartphone running the CFS application, the communication between the mobile device and the pads, and the placement of the pads on the patient&#39;s body; 
           [0024]      FIGS. 7A through 7L  are diagrams showing steps in the use of the CFS system; 
           [0025]      FIG. 8  is a drawing showing a possible modification of the pads; 
           [0026]      FIG. 9  is a drawing showing one possible configuration for the charger; 
           [0027]      FIG. 10A  is a perspective view showing another possible configuration for the charger; 
           [0028]      FIG. 10B  is a cross-sectional view taken along lines XB-XB of  FIG. 10A ; and 
           [0029]      FIG. 11  is a drawing showing another possible modification of the pads. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0030]    A preferred embodiment of the present invention and variations thereof will be set forth in detail with reference to the drawings, in which like reference numerals refer to like elements or steps throughout. 
         [0031]      FIG. 1  shows a pad  100  according to the preferred embodiment. The pad  100  includes a substrate  102  carrying a flexible circuit  104 , TENS pads  106 , and CFS blades  108 . An adhesive  110  is applied to allow adhesion to the patient&#39;s skin, and a cover  112  (not shown in  FIG. 1 , but shown in  FIG. 7B ) is disposed on the pad  100 . The flexible circuit  104  has a portion  114  formed in a pocket  116  in the substrate  102  to receive power from a pod (to be described below). 
         [0032]    The pad  100  is consumable, disposable, and self-adhesive. It has a flexible circuit, one-use gel pads, and one-use CFS blades. 
         [0033]      FIG. 2  shows multiple pads  100  in an over-the-counter consumer 12-pack  200  having a sheet  202  and an envelope  204 . Of course, the pads  100  could be packaged singly or in any number, and the configuration of the packaging can be changed as desired as long as the pads  100  are adequately protected. 
         [0034]      FIG. 3  shows a pod  300  for use with the pad  100 . The pod  300  is reusable and rechargeable and is inserted into the pocket  116  of the pad  100 . The pod  300  can have a surface antimicrobial treatment to assure cleanliness and decrease any possibility of contamination. In addition, or instead, a disinfecting device, to be described below, can be used, or the pods can be wiped with disinfecting cloths between uses. 
         [0035]      FIG. 4  is a circuit diagram showing the circuitry contained in the pod  300 . The pod  300  contains a 3V battery  402  and output circuitry  404  for providing a 50V output. The battery  402  has a life of 20 minutes and operates under control of a microelectronic controller  406  and a Bluetooth communication device  408 . Of course, any suitable values and any suitable communication protocol could be used instead. 
         [0036]      FIG. 5  shows an inductive pod charger  500  into which multiple pods  300  are inserted for inductive charging. 
         [0037]      FIG. 6  shows multiple pads  100  placed on the back of a patient P. A suitably programmed smartphone or other wireless device  600  communicates with the pods (not shown in  FIG. 6 ) using a Bluetooth connection  602 . 
         [0038]      FIGS. 7A through 7L  show steps in the use of the preferred embodiment. In  FIG. 7A , the patient P is suffering from lower-back and shoulder pain. In  FIG. 7B , the patient P peels off the cover  112  from the pad  100  and inserts a battery/controller pod  300 . In  FIG. 7C , the patient P places a pad, with the pod inserted, at each pain zone. In  FIG. 7D , the patient P runs the smartphone application on the smartphone  600  and selects the transducer locations on the application&#39;s graphical user interface  702 . The application can also prompt the patient on where to place the pads using diagrams or photographs taken by the doctor at the initial appointment. Of course, the order of performing the steps of  FIGS. 7B-7C  and the step of  FIG. 7D  could be reversed. In  FIG. 7E , the patient P chooses a treatment program for each zone on the graphical user interface  702 . The programs can be custom-designed by the user and saved and named if liked, or the doctor can set and lock each program. In  FIG. 7F , the patient P presses the “Start Treatment” button  704  on the graphical user interface  702 . The graphical user interface  702  can show intensity, program curves, and the like. The application can also play music or video or allow the patient to play a game. In  FIG. 7G , the pods  300  and the smartphone  600  communicate wirelessly over the Bluetooth connection  602  to control each pod  300  to load and start the appropriate treatment to the zone where it is located. In  FIG. 7H , the treatment programs are running, and the patient P can relax during treatment. In  FIG. 71 , the treatment programs are finished, and the patient P removes each pad  100  and removes each pod  300  from its corresponding pad. In  FIG. 7J , each pad, which is intended for a single use, is discarded. In  FIG. 7K , the pods  300  are placed into an inductive charger  500 . In  FIG. 7L , the process ends, and the patient&#39;s pain is relieved. 
         [0039]    The application can wirelessly transmit information after each treatment to the doctor for the patient&#39;s file. The details can include duration, program setting, date and time. The application can also provide regular reminders to help the patient tailor and follow treatment guidelines as fits the patient&#39;s schedule. Communication with the doctor&#39;s office can be by any suitable communication technology, e.g., the data connection or SMS functionality in the smartphone  600 . 
         [0040]    The use of a smartphone or tablet means less physical product to track, produce, repair, or update, since the application can be implemented on hardware that the patient likely already has. Alternatively, a dedicated device can be produced. Product updates can largely be done by releasing updates of the application. Such updates can upgrade the look/feel and performance of the user interface and the programs. 
         [0041]    The product will conform to the patient&#39;s aesthetics because the patient has already chosen the device and the cover. The user interface can also include options to customize such things as the color schemes. 
         [0042]    Small, independent transducers (pad/pod combinations) make placement, coverage, and focus easier. In a variation of the preferred embodiment, shown in  FIG. 8 , changeable color-coded rings  800  provide a visual reference for placement and program options in the user interface. 
         [0043]      FIG. 9  shows an example of an inductive charging pad  500 . The charging pad  500  has a dimple  902  into which each pod  300  can be snapped for charging. Some sort of contact charging can be provided instead. 
         [0044]      FIGS. 10A and 10B  are a perspective view and a cross-sectional view, respectively, of a charging box  1000  that charges one side and disinfects the other side simultaneously. The box  1000  includes an inductive charging mat  1002  and a capillary foam  1004  for applying a sterilization fluid  1006  to the pod  300 . 
         [0045]      FIG. 11  shows multiple sheets  1100  to keep different colored transducers  1102  separate. This can be useful if, for example, different types of transducers are provided. 
         [0046]    While a preferred embodiment and variations thereon have been set forth in detail above, those skilled in the art who have reviewed the present disclosure will readily appreciate that other embodiments can be realized within the scope of the invention. For example, numerical values are illustrative rather than limiting, as are disclosures of specific technologies, technical standards, and methods of charging the pods. Therefore, the present invention should be construed as limited only by the appended claims.