Apparatus and method for causing vasoconstriction by electrical stimulation

Abstract

An apparatus configured to be worn on a hand or a foot, comprising a plurality of electrodes arranged to be located on one or more respective phalanges when the apparatus is attached to the hand or the foot, a support structure configured to attach the apparatus to the hand or the foot and hold the plurality of electrodes, and a control device configured to control the application of signals to the plurality of electrodes. A feedback sensor may be provided and arranged on the finger to monitor the properties of the underlying tissue.

Description

Technical Field

[0001] The present invention relates to a wearable device configured to apply electrical stimulation to the autonomic (sympathetic) nervous system to achieve targeted vasoconstriction.

Background Art

[0002] In the field of chemotherapy treatment, one of the widely observed side effects is chemotherapy-induced peripheral neuropathy (CIPN). Peripheral neuropathy manifests as tingling or numbness in the hands and feet, pain in the hands and feet, and loss of function after chemotherapy, which may lead to a decline in the quality of life.

[0003] The toxicity of chemotherapy drugs is thought to cause nerve damage and result in CIPN. This is a cumulative effect where the toxicity level increases with each chemotherapy treatment. This often leads to a reduction or discontinuation of chemotherapy and can worsen the treatment outcome. CIPN is thought to affect the majority of patients undergoing chemotherapy treatment, meaning that addressing this condition is an urgent unmet clinical need.

[0004] Current methods for treating CIPN are not well tolerated by patients and are not easy for healthcare providers to apply. One of the existing solutions is cryotherapy to cause vasoconstriction. However, such devices have insufficient patient comfort and tolerance due to the very low temperatures required. Due to the length of some chemotherapy sessions, cold inserts need to be replaced regularly or several devices are required, which requires a lot of time from healthcare providers. Such devices are also known to cause burns such as frostbite.

Summary of the Invention

[0005] According to a first aspect of the present invention, there is provided a device configured to be worn on a hand or a foot, the device comprising: a plurality of electrodes arranged to be located on one or more respective phalanges when the device is attached to the hand or the foot; a support structure configured to attach the device to the hand or the foot and hold the plurality of electrodes; and a control device configured to control the application of signals to the plurality of electrodes.

[0006] Each of the plurality of electrodes may be arranged to be located on the proximal phalanx of each respective finger. Alternatively, each of the plurality of electrodes may be arranged to be located on the middle phalanx of each respective finger. Alternatively, each of the plurality of electrodes may be arranged to be located on the distal phalanx of each respective finger. Alternatively, each of the plurality of electrodes may be arranged to be located on the proximal phalanx and the middle phalanx of each respective finger. Alternatively, each of the plurality of electrodes may be arranged to be located on all of the phalanges of each respective finger. The device may further comprise one or more reference electrodes arranged away from the fingers of the hand or the toes on the hand or the foot. The one or more reference electrodes may be positioned on the palm of the hand. The one or more reference electrodes may be positioned on the back of the hand. The one or more reference electrodes may be positioned on the sole of the foot. The one or more reference electrodes may be positioned on the top of the foot.

[0007] The device may further comprise a sensor held by the support structure, the sensor being located on the finger and configured to monitor the characteristics of the underlying tissue.

[0008] The sensor may include a photoplethysmography sensor configured to output a signal to the control device. The control device may be configured to derive a peripheral perfusion index of the underlying tissue based on the signal.

[0009] The sensor may include a surface potential sensor for the peripheral autonomic nerve configured to measure the activity of the autonomic nerve tissue underlying the sensor.

[0010] The sensor may include a surface electromyogram sensor configured to measure the activity of somatic nerve tissue beneath the sensor.

[0011] The control device may be configured to dynamically adjust the characteristics of the signals applied to the plurality of electrodes based on the signals received from the sensor.

[0012] The device may include a plurality of sensors, each of the plurality of sensors being located on a respective finger. Alternatively, some partial collections of fingers may have corresponding sensors.

[0013] The control device may be configured to periodically apply signals to the plurality of electrodes with a 50% duty cycle.

[0014] The device may further include auxiliary electrodes arranged to be located on the forearm or foreleg when the device is attached to the hand or foot. The auxiliary electrodes may be arranged to provide an analgesic effect when stimulated.

[0015] The device may include clothing configured to be worn on the hand, and optionally, the clothing is a glove or a mitt. It may be advantageous to configure the clothing as a glove because while the electrical stimulation is being applied, the patient can maintain a certain degree of movement of the fingertips, so that some work can be continuously performed during the treatment.

[0016] The device may include clothing configured to be worn on the foot, and optionally, the clothing is a sock or a shoe.

[0017] According to a second aspect of the present invention, a method of causing vasoconstriction in a peripheral nerve using electrical stimulation, the method comprising attaching a device comprising a plurality of electrodes to a patient's hand or foot such that each electrode is positioned on one or more respective phalanges of the patient, applying a series of test signals using the plurality of electrodes to calibrate a threshold of perception at which the patient perceives a test signal, and applying a treatment signal using the plurality of electrodes, the treatment signal being described as being below the threshold of perception revealed to that patient.

[0018] The method may further comprise monitoring the level of vasoconstriction using one or more sensors and adjusting one or more parameters of the treatment signal based on the monitored level of vasoconstriction.

[0019] The device may comprise auxiliary electrodes arranged to be located on the forearm or lower leg when the device is attached to the patient's hand or foot, and the method may further comprise, after applying the treatment signal, applying one or more auxiliary signals using the auxiliary electrodes to cause an analgesic effect and / or a massage effect on the underlying tissue.

[0020] To more fully understand the general concepts described in the preceding section, embodiments thereof will be described with reference to the accompanying drawings.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4a

Figure 4b

Figure 4c

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

DETAILED DESCRIPTION OF THE INVENTION

[0022] Referring to FIG. 1, an apparatus 100 having the form of a glove is shown. The apparatus 100 includes a support structure 102 that enables the apparatus 100 to be attached to a user's hand. The apparatus 100 also includes a plurality of electrodes 104-1 to 104-5 (generally shown as 104). Each electrode 104 is disposed within each finger of the glove so as to be positioned on each respective finger of the user when the user is wearing the glove. The electrode 104 may be located on the upper side of each finger of the glove so as to contact the upper surface of each finger, or may be located on the lower side of each finger of the glove so as to contact the lower surface of each finger. Alternatively, each electrode 104 may have a ring shape or a partial ring shape so as to partially or completely wrap around each respective finger.

[0023] As shown in FIG. 1, the electrode 104 may extend longitudinally along the length of the user's finger. Alternatively, the electrode 104 may be arranged transversely to the user's finger. In such a configuration, each electrode 104 may be partially wound around each finger so as to cover both the inner and outer sides of the finger.

[0024] In the embodiment shown in FIG. 1, the electrodes 104-1 to 104-5 are each located on the proximal phalanx of each finger. In some other embodiments described later, the electrodes 104-1 to 104-5 may be located on the middle phalanx or the distal phalanx, or may extend over two or more phalanges.

[0025] In addition to these, a reference electrode 105 is arranged on the palm or above / around the wrist of the hand. Each of the electrodes 104-1 to 104-5 can use the common reference electrode 105 together. Alternatively, a plurality of reference electrodes 105 may be provided such that each electrode 104 has a corresponding reference electrode 105. As shown in FIG. 1, the reference electrode 105 may extend longitudinally along the length of the user's palm. Alternatively, the reference electrode 105 may be arranged across the user's palm (transversely to the direction of the fingers). Usually, the reference electrode 105 is arranged away from the fingers.

[0026] When the reference electrode 105 is arranged on the user's palm, it has been observed that the maximum vasoconstriction effect can be obtained. However, the reference electrode 105 may alternatively be located on the back of the user's hand.

[0027] The electrodes 104-1 to 104-5 may be the anodes of the system, and the reference electrode may be the cathode. In this configuration, a signal is applied to the electrode 104 to stimulate along the user's finger.

[0028] The device 100 also includes a control system 106 that is supported by the wrist portion of the glove in this embodiment.

[0029] The support structure 102 may be a glove having a modified area for holding the electrodes 104, and an elongated wrist portion having a modified area or pocket for holding the control system 106. The support structure 102 may include holes or other access points to allow adjustment or replacement of each electrode 104. In some other embodiments, the support structure 102 may include a frame or a mesh structure. This can increase the airflow to the hand compared to a glove. The electrodes 104, 105 and the control system 106 may be held by adjustable and / or elastic straps. Alternatively or additionally, the electrodes may have an adhesive portion for fixing them to the user's skin.

[0030] The control system 106 can include a power source, a pulse generator, and a processing unit (optionally incorporating a feedback circuit) for controlling the application of electrical signals to the electrodes 104. Each of the electrodes 104 can have a separate connection to the control system 106 for this purpose. In some embodiments, the reference electrode may be disposed directly under the control system and / or may be integral with the control system. The control system may also include additional elements that are described in more detail with respect to FIG. 6.

[0031] FIG. 2 shows a system 200 according to some other embodiments in which the control system 106 is disposed outside the device 202. The device 202 includes a hub 204 to which all of the electrodes 104 and the reference electrode 105 are connected. The hub 204 can be sequentially connected and disconnected to the control system 106 via ports of the hub 204 and / or the control system 106. This configuration reduces the complexity of the device 202 and allows the control system 106 to be used with different devices 202, which means that fewer control systems 106 are required.

[0032] In both the embodiments of FIGS. 1 and 2, the electronic components of the devices 100, 202 may be removable from the support structure 102, thereby allowing the support structure to be washed. Alternatively, some or all of the electronic components may be implanted in or otherwise permanently attached to the support structure 102. The support structure 102 may be made of an elastic material to allow for use by patients with different sized hands. Alternatively or additionally, the devices 100, 202 may be provided in a variety of different sizes.

[0033] Referring to FIG. 3, a device 300 according to a further embodiment is shown. The device 300 includes electrodes 104, a reference electrode 105, and a control system 106 in the same arrangement as disclosed in the embodiment of FIG. 1. Further, the device 300 includes at least one sensor 302-1 to 302-5 (generally shown as 302) held by the support structure 102. Each sensor 302 is arranged to be positioned on a finger and is configured to monitor the characteristics of the underlying tissue.

[0034] FIG. 3 shows sensors 302 located on each finger, although in some embodiments only a portion of the illustrated sensors may be present. In some embodiments, only a single sensor may be used. Several different measurement techniques may be used for the sensors 302. In some embodiments, the sensors may include a photoplethysmography (PPG) sensor configured to output a signal to the control system 106. The PPG sensor is located on the underside of the glove so as to contact the pad of each finger when the patient is wearing the glove. The control system 106 is configured to receive a signal from the PPG sensor and derive an indicator of peripheral perfusion (such as peripheral perfusion index - PPI) in the underlying tissue based on the received optical signal. The PPI indicates the degree of blood flow in the finger.

[0035] In some other embodiments, the sensor includes a surface potential sensor for the peripheral autonomic nerves. These are configured to measure the potential indicating the activity of the autonomic nerve tissue underlying the sensor. The control system 106 is configured to receive signals from the surface potential sensor for the peripheral autonomic nerves and determine the degree of blood flow in the finger.

[0036] In some other embodiments, the sensor includes a surface electromyogram sensor. These are configured to measure the activity of the somatic nerve tissue underlying the sensor.

[0037] In some embodiments, the electrodes 104 used to apply a stimulus to the finger may also be used as sensors. In the above-described embodiments, the surface potential sensor for the peripheral autonomic nerves or the surface electromyogram sensor includes electrodes. These may be the same electrodes 104 used to stimulate the finger. As will be described below with reference to FIG. 4, the stimulus is applied periodically. During the period when no signal is applied to the electrodes 104, they may be used as sensors.

[0038] When an electrical stimulus is applied to the electrodes, it becomes possible to monitor the effectiveness of the treatment in real time by measuring the blood flow in the finger at that time. The information from the sensor can also be used as feedback means for dynamically changing the intensity, frequency, and / or periodicity of the signal applied to the electrodes in order to achieve the highest level of vasoconstriction that continues during the chemotherapy period.

[0039] FIG. 4a is a graph 400 showing the results from a prototype device in which a single electrode was attached to the little finger with a reference electrode attached to the palm. The electrode extended across both the proximal phalanx and the middle phalanx. A PPG sensor was placed at the fingertip of the little finger. The value of the peripheral perfusion index was derived from the optical signal received from the PPG sensor during the test. A 30-second adaptation period was given before applying any signal. Then, an electrical stimulus was applied for 10 seconds, followed by a 10-second off period, and this was repeated periodically. The frequency of the applied signal was approximately 50 hz, the current was 15 mA, and the pulse width was approximately 100 μs.

[0040] As can be seen from the figure, during the initial period of electrical stimulation, the PPI decreased rapidly to approximately 20% of the pre-stimulation value. When the stimulation was removed, the PPI increased over the period without stimulation but decreased again when the stimulation was applied again. As can be seen from graph 400, when electrical stimulation was applied periodically for 10 seconds at a 50% duty cycle, the average PPI during the test period was approximately 40% of the pre-stimulation value. This result indicates that substantial vasoconstriction can be achieved by targeted application of periodic electrical signals to the phalanges. The possible mechanism is by inhibition of local nitric oxide release and subsequent activation of the local autonomic (sympathetic) response.

[0041] Figure 4b includes a series of graphs that first show the pattern of change in stimulation and then some experimental results of the root mean square of the PPG signal over time. These results were obtained using the apparatus shown in Figure 3, where electrode 104 was located on the proximal phalanx of the finger and the reference electrode was located on the palm. The PPG sensor 302 was placed in contact with the ventral side of each finger. After attaching the apparatus 300 to the user, there was a derived stabilization period without the signal being applied.

[0042] Subsequently, electrical stimulation was applied periodically for 20 seconds at a 50% duty cycle. The frequency of the applied signal was approximately 80 hz and the pulse width was approximately 180 μs. The first 20 seconds of the measurement period without the signal being applied was used as the baseline, and in graphing, the signal was normalized with respect to the baseline to enable comparison of the responses between fingers. As seen in the first drawing of Figure 4b, when starting or resuming stimulation, the apparatus has a linear increase over 3 seconds. At pause, the apparatus stops the stimulation with a linear decrease over 1 second.

[0043] Next, six different shapes representing the results from the user's left thumb, index finger, middle finger, ring finger, and little finger are shown. The last shape shows the result from the user's big toe (hallux) (see the description of FIG. 8 below). As can be seen from the figure, when a stimulus signal is applied, there is a significant decrease in the PPG signal intensity caused by substantial vasoconstriction in the peripheral nerves of the finger pad. These tests demonstrate the apparent ability to cause vasoconstriction and maintain this reduced blood flow over an extended period.

[0044] During these tests, the inventors noticed that it was difficult to hold the PPG probe against the thumb because the PPG probe deformed, as evidenced by the progressive decrease in the vasoconstriction effect detected in Shape 1.

[0045] FIG. 4c includes a series of graphs that first show the pattern of stimulus change and then some experimental results of the root mean square of the PPG signal over time, tested with electrode 104 at different positions. The pattern of stimulus change is the same as that described with reference to FIG. 4b. After attaching the device to the user, there was similarly a derived stabilization period when no signal was applied. The first 20 seconds of the measurement period when no signal was applied was used again as the baseline, and the signal was normalized with respect to the baseline in graphing.

[0046] Shape 2a in FIG. 4c had an electrode located on the proximal phalanx of the left index finger, the reference electrode was located on the palm, and the PPG sensor was located on the pad of the left index finger. Shape 2b in FIG. 4c had an electrode located on the middle phalanx of the left index finger, the reference electrode was located on the palm, and the PPG sensor was located on the pad of the left index finger. Shape 2c in FIG. 4c had an electrode located on the distal phalanx of the left index finger, the reference electrode was located on the palm, and the PPG sensor was located on the pad of the left index finger.

[0047] As can be seen from the figures, when the electrode is located on the proximal phalanx, the largest decrease in the PPG signal during stimulation is observed, and usually the effect is more pronounced with stimulation on the proximal and middle phalanges. However, in all cases, a continuous long-term decrease in the PPG signal is observed, which is due to continuous vasoconstriction and decreased blood flow at the tip of the finger.

[0048] Referring to FIG. 5, an apparatus 500 according to a further embodiment is shown. The apparatus 500 includes an elongated electrode 104 that extends along all of the phalanges of the finger. In other respects, the electrode 104 is the same as those described above. The reference electrode 105 is at a position on the palm (or back of the hand) as described above. The electrodes are connected to and controlled by a control system 106 similar to those already described. Further, the apparatus 500 may optionally include an auxiliary electrode 502 supported on the elongated wrist portion of the glove so as to be located on the patient's forearm when the patient is wearing the glove. The position of the auxiliary electrode 502 is such that applying stimulation results in vasodilation of the underlying tissue. The auxiliary electrode may be a standard TENS electrode. Thus, the auxiliary electrode 502 is not used during the chemotherapy period, but can be activated after treatment for the purpose of increasing peripheral blood flow and providing an analgesic or massage effect.

[0049] Referring to FIG. 6, an apparatus 600 according to a further embodiment is shown. The apparatus 600 includes the electrode 104, the reference electrode 105, and the control system 106 in the same arrangement as disclosed in the embodiment of FIG. 1. However, the finger end of the glove is removed so that the patient's fingertip is exposed when the patient is wearing the apparatus 600. Thereby, the apparatus 600 can be used in combination with an existing PPI monitor such as a pulse oximeter. This design can also allow for greater movement of the fingertips for performing tasks while the patient is undergoing chemotherapy treatment.

[0050] FIG. 7 schematically shows an electronic system 700 for controlling the operation of the aforementioned device. The electronic system 700 includes a control device 702, the aforementioned electrode 104, a reference electrode 105, one or more of the aforementioned monitoring sensors 302, and a power supply 704. Optionally, the electronic system may also include a display 706, a monitoring station 708 and / or a wireless transceiver 710.

[0051] The control device 702 is configured to control the operation of the other components of the electronic system 700. The control device 702 may be, for example, a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), etc. Alternatively, the control device 702 may comprise dedicated processing hardware, for example, programmable hardware incorporating a RISC processor or firmware. The control device 702 may comprise a plurality of processors. The control device 702 may also comprise a memory, for example, a program memory for storing program code (e.g., software or firmware). The program memory may be, for example, a non-volatile memory such as a read-only memory (ROM), a flash memory, or a magnetic drive memory.

[0052] The display 706 may be a standard LCD display, or a touch sensor type display based on capacitive or resistive sensing technology. The display 706 may be removably or permanently attached to the support structure 102 of the device. If the device is a glove, the display 706 may be located on the elongated wrist portion of the glove such that the patient can easily view it without interfering with either the chemotherapy treatment or the electrical stimulation provided by the device. The power supply 704 may be any suitable type of battery and may supply power to all of the other elements of the electronic system 700. The power supply 704 may also be held on or within the support structure 102.

[0053] The electronic system 700 may also optionally include a wireless transceiver 710 for communicating with an external device 712. The wireless transceiver 710 includes a network interface necessary for communicating via 3G, 4G, 5G, Bluetooth, WiFi, Zigbee, or any combination of these protocols, and may further include an antenna. The wireless transceiver 710 may communicate directly with the external device 712, or the communication may be routed via an intermediate device, router, server, or base station. The external device 712 may be a smartphone, tablet, PDA, or other mobile computing device. The external device 712 may be assigned to a patient or the patient's physician or other healthcare provider. The external device 712 may execute an application or other software to display information regarding the operation of the electronic system 700. Additional information regarding the patient's chemotherapy, such as the duration and remaining time of the current treatment, may be aggregated in the application. Information received from the monitoring sensor 302 may be displayed on the display of the external device 712. The application or other software on the external device 712 may also be capable of controlling the electronic system 700, for example, to initiate, stop, and / or pause electrical stimulation, or to change parameters of the applied signal such as current or periodicity (duty cycle). The external device 712 also includes a memory (not shown) that can be used to record any information received from the monitoring sensor 302 for later review or subsequent transmission.

[0054] In some embodiments, the control device 702 and the power supply 704 may be incorporated into the control system 106 shown in FIGS. 1, 2, 5, and 6. The display 706 and the wireless transceiver 710, if present, may also be part of the control system 106. The electrodes 104 and the monitoring sensor 302, if present, need to be remote from the control system 106 so that these components can be placed on the user's finger.

[0055] In some other embodiments, the electronic system 700 includes a monitoring station 708 that can connect to the control device 702. The monitoring station 708 is external to the device and may include a computer terminal. The monitoring station 708 can receive information from the monitoring sensor 302 during use of the device. Thereby, a physician, nurse, or other healthcare provider can observe the effects of the electrical stimulation in real time. In some embodiments, the monitoring station 708 may be able to issue commands to the control device 702 to change parameters of the applied signal, such as current or periodicity (duty cycle). This may be done automatically as a result of feedback from the monitoring sensor 302 to maximize a decrease in peripheral blood flow, or to keep peripheral blood flow at or within a defined limit.

[0056] During use, the control device 702 controls the application of an electrical signal to the electrodes 104 by the power supply 704 according to a preset program. The preset program may be stored in a memory on the control device, a separate memory (not shown) forming part of the electronic system 700, or on the monitoring station 708.

[0057] The control device 702 receives a feedback signal from the monitoring sensor 302 and controls the display of this information on the display 706 if the display 706 is present. The feedback information may be transmitted to the monitoring station 708 for display and / or storage. The feedback information may also be transmitted to an external device 712 via the wireless transceiver 710 for display and / or storage. The control device 702 may receive commands from the monitoring station 708 or the external device 712 to change one or more parameters of the applied signal.

[0058] Referring to FIG. 8, an apparatus 800 according to a further embodiment is shown. The apparatus 800 includes a sock or other clothing configuration that is worn on a patient's foot. The apparatus 800 includes a support structure 802 that enables the apparatus 800 to be attached to the user's foot.

[0059] Device 800 includes a plurality of electrodes 104. Each electrode 104 is disposed on each toe of the sock such that it is positioned on each respective toe of the user when the user is wearing the sock. The electrode 104 may be positioned above each toe region so as to contact the upper surface of each toe, or may be positioned below each toe region so as to contact the lower surface of each toe. Alternatively, each electrode 104 may have a ring shape or a partial ring shape so as to partially or completely wrap around each respective toe. In addition to these, a reference electrode 105 is disposed in contact with / around the back of the foot. In some alternative embodiments, the reference electrode 105 is located on the upper part of the foot portion of the sock or on the ankle portion of the sock. Typically, the reference electrode 105 is disposed away from the toes.

[0060] Device 800 also includes a control system 106 as described above, which in this embodiment is supported on the upper part of the foot portion of the sock. The control system 106 of FIG. 8 may include some of the elements of the electronic system 700 as described above, may be connected to the monitoring station 708 as described above, and / or may communicate with the external device 712.

[0061] The support structure 802 may be a sock having a modified region for holding the electrodes 104. The support structure 802 may include holes or other access points to enable adjustment or replacement of each electrode 104.

[0062] Similar to the glove embodiments described above, the electrodes 104 in the sock embodiment of FIG. 8 are positioned to apply electrical stimulation directly to the phalanges, in this case the phalanges of the toes. When an electrical signal is applied in this way, the blood vessels in the toes vasoconstrict, reducing the accumulation of toxicity in the toes from chemotherapy drugs, and as a result reducing nerve damage. The electrodes 104 may also function as sensors for measuring the activity of the underlying nerve tissue in order to monitor the effectiveness of the electrical stimulation and function as feedback to change the electrical stimulation as needed. In some other embodiments, one or more of the toe portions of the device 800 may further be provided with PPG sensors that are capable of independently monitoring blood flow and deriving PPI. Alternatively, one or more ends of the toe portions may be removed to allow a separate PPG sensor to be attached to the toes.

[0063] The device 800 may also include an auxiliary electrode (not shown) supported by an elongated ankle portion (not shown) of the sock such that the auxiliary electrode is positioned on the patient's forefoot. As described above, the auxiliary electrode is not used during chemotherapy, but can be used after treatment to provide an analgesic or massage effect.

[0064] Although the device 800 is shown as having separate portions for each toe, the device 800 may alternatively comprise a single internal space and the electrodes 104 are positioned such that they can be accurately placed on the patient's toes. Further, although the device 800 is depicted as a sock having separate portions for each toe, alternatively the device may take the form of an overshoe or a shoe.

[0065] Referring again to FIG. 4b, the experimental results obtained by applying a signal to the big toe (the great toe of the foot) are shown in graph 6. In this experiment, the electrode was positioned on the proximal phalanx of the big toe and a PPG sensor was attached to the ventral side of the toe. As can be seen from the figure, significant and sustained vasoconstriction in the toe can be obtained using this device.

[0066] FIG. 9 is a flowchart showing an exemplary method for applying a treatment that causes vasoconstriction in a peripheral nerve using electrical stimulation. This treatment can be applied simultaneously with chemotherapy, i.e., during the administration of chemotherapeutic agents, for the purpose of reducing the accumulation of toxicity in the peripheral nerves during chemotherapy that can lead to peripheral neuropathy.

[0067] The process starts in step 900 by attaching a device including a plurality of electrodes to the patient's hand or foot, with each electrode positioned on one or more respective phalanges of the patient's fingers. The device can be any of the devices described with reference to FIGS. 1 - 3, 5, 6, or 8.

[0068] In step 902, a series of test signals are applied using the plurality of electrodes to calibrate the threshold of perception at which the patient perceives the test signals. Ideally, the level of the electrical signals used during treatment is hardly perceptible to the user, both for improved comfort and improved utilization of the treatment. Since each patient has a different perception threshold, it is necessary to determine the perception level calibrated for each patient prior to treatment.

[0069] In step 904, a treatment signal is applied using the plurality of electrodes, and the treatment signal is below the threshold of perception determined for that patient.

[0070] In an optional further step 906, one or more sensors are used to monitor the level of vasoconstriction. These sensors can be any of the aforementioned sensors 302. In an optional further step 908, one or more parameters of the treatment signal are adjusted based on the monitored level of vasoconstriction. The adjustment to the treatment signal is made within predetermined limits and takes into account the perception threshold of the individual patient. In an optional further step 910, one or more auxiliary signals are applied using auxiliary electrodes to cause an analgesic effect and / or a massage effect on the underlying tissue. This step is performed after the treatment signal is completed.

Description of the Reference Numerals

[0071] 100 device 102 support structure 104 electrode 104-1 First electrode etc. 105 reference electrode 106 control system 200 system 202 device 204 hub 300 device 302 sensor 302-1 First sensor etc. 400 graph 500 device 502 auxiliary electrode 600 device 700 electronic system 702 control device 704 power supply 706 display 708 monitoring station 710 wireless transceiver 712 external device 800 device 802 support structure

Claims

1. A device configured to be worn on the hand or foot, The aforementioned device is When the device is attached to the hand or foot, a plurality of electrodes are arranged to be positioned on one or more of the respective phalanges, A support structure configured to be attached to the hand or foot and to hold the plurality of electrodes, and An apparatus comprising a control device configured to control the application of signals to the plurality of electrodes.

2. The apparatus according to claim 1, wherein each of the plurality of electrodes is positioned on the proximal phalanx of each finger.

3. The apparatus according to claim 1, wherein each of the plurality of electrodes is positioned on the middle phalanx of each finger.

4. The apparatus according to claim 1, wherein each of the plurality of electrodes is positioned on the distal phalanx of each finger.

5. The apparatus according to claim 1, wherein each of the plurality of electrodes is positioned on the proximal and middle phalanges of each finger.

6. The apparatus according to claim 1, wherein each of the plurality of electrodes is positioned on all of the phalanges of each finger.

7. The apparatus according to claim 1 or 4, further comprising one or more reference electrodes positioned on the hand or foot, separated from the fingers or toes.

8. The device further comprises a sensor held by the support structure, The apparatus according to claim 1, wherein the sensor is positioned on a finger and configured to monitor the characteristics of the underlying tissue.

9. The apparatus according to claim 8, wherein the sensor includes a photoplethysmography sensor configured to output a signal to the control device.

10. The apparatus according to claim 9, wherein the control device is configured to derive a peripheral perfusion index of the underlying tissue based on the signal.

11. The apparatus according to claim 8, wherein the sensor includes a peripheral autonomic nerve surface potential sensor configured to measure the activity of autonomic nerve tissue located beneath the sensor.

12. The apparatus according to claim 8, wherein the sensor includes a surface electromyography sensor configured to measure the activity of somatic nerve tissue located beneath the sensor.

13. The apparatus according to any one of claims 8 to 12, wherein the control device is configured to dynamically adjust the characteristics of the signals applied to the plurality of electrodes based on the signals received from the sensor.

14. The apparatus according to any one of claims 8 to 12, wherein the apparatus comprises a plurality of sensors, each of which is located on a finger.

15. The apparatus according to claim 1, wherein the control device is configured to periodically apply a signal to the plurality of electrodes with a duty cycle of 50%.

16. The apparatus according to claim 1, further comprising an auxiliary electrode positioned to be located on the forearm or foreleg when the apparatus is attached to the hand or foot.

17. The apparatus according to claim 1, comprising clothing configured to be worn on the hand, wherein the clothing is optionally a glove or a mitt.

18. The apparatus according to claim 1, comprising clothing configured to be worn on the foot, wherein the clothing is optionally a sock or a shoe.

19. A method for inducing vasoconstriction in peripheral nerves using electrical stimulation, The aforementioned method, A device equipped with multiple electrodes is attached to the patient's hand or foot such that each electrode is positioned on one or more of the patient's phalanges. To calibrate the perceptual threshold at which the patient perceives the test signals, a series of test signals are applied using the plurality of electrodes, and A method comprising applying a therapeutic signal using the plurality of electrodes, wherein the therapeutic signal is below the threshold of perception revealed to the patient.

20. Monitoring the level of vasoconstriction using one or more sensors, and Adjusting one or more parameters of the therapeutic signal based on the monitored level of vasoconstriction, The method according to claim 19, further comprising:

21. The apparatus comprises an auxiliary electrode positioned to be located on the forearm or foreleg when the apparatus is attached to the patient's hand or foot, and the method further comprises, after applying the therapeutic signal, applying one or more auxiliary signals using the auxiliary electrode to induce an analgesic and / or massage effect on the underlying tissue, according to claim 19 or 20.

Images