Tibial nerve electrical stimulation system

Abstract

The embodiment of the utility model provides a tibial nerve electrical stimulation system. The tibial nerve electrical stimulation system comprises an electrical stimulator and an electrode plate, the electrical stimulator is connected with the electrode plate; wherein the electrical stimulator is used for generating an electrical stimulation signal and transmitting the electrical stimulation signal to the electrode plate; the electrical stimulation signal is a pulse signal with curve envelope; and the electrode slice is connected with a human body and is used for receiving an electrical stimulation signal sent by the electrical stimulator and transmitting the electrical stimulation signal to a tibial nerve.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of medical technology, and specifically to a tibial nerve electrical stimulation system. Background Art

[0002] In the current electrical stimulation scenario, the tibial nerve electrical stimulation system usually uses a square wave pulse stimulation signal to electrically stimulate the patient. When the nerve stimulation intensity reaches the effective treatment level, the patient will feel a strong tingling sensation, causing discomfort to the patient, greatly reducing the compliance with the treatment and thus reducing the effectiveness of the treatment. Utility Model Content

[0003] An embodiment of the present application provides a tibial nerve electrical stimulation system.

[0004] The embodiment of the present application provides a tibial nerve electrical stimulation system, which includes: an electrical stimulator and an electrode sheet; the electrical stimulator is connected to the electrode sheet; wherein,

[0005] The electrical stimulator is used to generate an electrical stimulation signal and transmit the electrical stimulation signal to the electrode sheet; the electrical stimulation signal is a pulse signal with a curved envelope;

[0006] The electrode sheet is connected to the human body and is used to receive the electrical stimulation signal sent by the electrical stimulator and transmit the electrical stimulation signal to the tibial nerve.

[0007] Through the tibial nerve electrical stimulation system provided in the embodiment of the present application, a pulse electrical stimulation signal with a curved envelope is generated by an electrical stimulator, and the electrical stimulation signal is transmitted to the tibial nerve through an electrode connected to the electrical stimulator. The treatment device can gradually increase or decrease the stimulation intensity with a higher resolution within the same change amplitude, so that the patient can adapt to each change more easily without feeling sudden strong tingling, thereby increasing the tolerance of the therapy. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0009] Figure 1 A schematic diagram of the placement of electrodes for the tibial nerve electrical stimulation system provided in an embodiment of the present application;

[0010] Figure 2 Schematic diagram of the electrical stimulation signal provided in the embodiment of the present application Figure 1 ;

[0011] Figure 3 Schematic diagram of the structure of the tibial nerve electrical stimulation system provided in the embodiment of the present application Figure 1;

[0012] Figure 4 Schematic diagram of the structure of the electrical stimulation signal generating module provided in the embodiment of the present application Figure 1 ;

[0013] Figure 5 A schematic diagram of the structure of the constant current module, H-bridge circuit and MCU provided in the embodiment of the present application;

[0014] Figure 6 A schematic structural diagram of a boost module provided in an embodiment of the present application;

[0015] Figure 7 Schematic diagram of the structure of the electrical stimulation signal generating module provided in the embodiment of the present application Figure 2 ;

[0016] Figure 8 Schematic diagram of the electrical stimulation signal provided in the embodiment of the present application Figure 2 ;

[0017] Figure 9 This is a schematic diagram of the structure of the electrical stimulator provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The following will describe the technical solutions in the embodiments of this application in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0019] It should be noted that in the embodiments of the present application, the term "and / or" is merely a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the embodiments of the present application, the character " / " generally indicates that the associated objects are in an "or" relationship.

[0020] In the description of the embodiments of the present application, the term "corresponding" may indicate a direct or indirect correspondence between the two, or an association relationship between the two, or a relationship between indication and being indicated, configuration and being configured, etc.

[0021] To facilitate understanding of the technical solutions of the embodiments of the present application, the relevant technologies of the embodiments of the present application are described below. The following relevant technologies can be arbitrarily combined with the technical solutions of the embodiments of the present application as optional solutions, and they all fall within the protection scope of the embodiments of the present application.

[0022] like Figure 1 As shown, Figure 1 This is a schematic diagram of the electrode placement for the tibial nerve electrical stimulation system provided in an embodiment of the present application. Electrode 1 and Electrode 2 correspond to the locations of the tibial nerve in the calf or at the ankle branches, respectively. The tibial nerve stimulation signal is generated by the electrical stimulator and then transmitted via wires to the electrodes attached to the corresponding locations of the tibial nerve.

[0023] Because the tibial nerve contains nerve fibers from L4 to S3, which originate from the same spinal cord segment as the nerve fibers that control the bladder and pelvic floor, it can treat overactive bladder by stimulating somatic afferent components to inhibit bladder afferent activity and block the transmission of abnormal signals to the spinal cord and brain, thereby achieving "neural regulation."

[0024] Figure 2 Schematic diagram of the electrical stimulation signal provided in the embodiment of the present application Figure 1 ,like Figure 2 As shown, the electrical stimulation signal is a square wave pulse with a frequency of 20 Hz (corresponding to a period of 50 ms) and a pulse width of 200 us. When the nerve stimulation intensity reaches an effective treatment level, the patient will feel a strong tingling sensation, causing discomfort in the patient, affecting the patient's compliance with the treatment, and affecting the treatment effect.

[0025] refer to Figure 3 , Figure 3 Schematic diagram of the structure of the tibial nerve electrical stimulation system provided in the embodiment of the present application Figure 1 ,like Figure 3 As shown, the tibial nerve electrical stimulation system includes: an electrical stimulator and an electrode sheet; the electrical stimulator is connected to the electrode sheet; wherein,

[0026] The electrical stimulator is used to generate an electrical stimulation signal and transmit the electrical stimulation signal to the electrode sheet; the electrical stimulation signal is a pulse signal with a curved envelope;

[0027] The electrode sheet is connected to the human body and is used to receive the electrical stimulation signal sent by the electrical stimulator and transmit the electrical stimulation signal to the tibial nerve.

[0028] The electrode is placed on the stimulation point of the tibial nerve of the human body, and electrical stimulation is performed through a pulse electrical stimulation signal with a curved envelope. The stimulation intensity can be gradually increased or decreased within a smaller amplitude range, reducing the patient's pain and improving the treatment effect.

[0029] Exemplarily, the electrical stimulator includes an electrical stimulation signal generating module, which is used to generate a pulse signal with a curve envelope.

[0030] Example 1

[0031] refer to Figure 4 , Figure 4Schematic diagram of the structure of the electrical stimulation signal generating module provided in the embodiment of the present application Figure 1 In this embodiment, the electrical stimulation signal generation module includes a constant current module, a microcontroller (MCU), and an H-bridge circuit. The constant current module is used to provide a stable current to the H-bridge circuit, and the MCU is used to control the H-bridge circuit to output a pulse signal with a curved envelope.

[0032] refer to Figure 5 , Figure 5 This is a structural diagram of the constant current module, H-bridge circuit and MCU provided in the embodiment of the present application, as shown in FIG. Figure 5 As shown, the H-bridge circuit includes: Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) Q2, MOSFET Q3, MOSFET Q4, MOSFET Q5; the gate of each MOSFET is connected to the MCU, respectively, for receiving control signals SW1, SW2, SW3, SW4 sent by the MCU. Q2, Q3, Q4, Q5 correspond to the control signals SW1, SW2, SW3, SW4, respectively; the source of Q2 is connected to the drain of Q3 and then to one electrode, and the source of Q4 is connected to the drain of Q5 and then to another electrode. The two electrodes are connected to the human body.

[0033] The constant current module includes: operational amplifier U3.1, resistor RS1, capacitor U4, resistor RS3, resistor RS2, and an operational amplifier equipped with a 5V regulated DC power supply, wherein the DAC is connected to the positive input terminal of the operational amplifier, and the negative terminal of the operational amplifier is the corresponding Iout feedback signal and transistor Q6, and the collector of Q6 is connected to the H-bridge circuit; wherein, the base current of the transistor Q6 is adjusted by the feedback information of the operational amplifier, thereby achieving the effect of adjusting the output current, which is used to ensure that there is a stable current output when the H-bridge switches to output a complex envelope waveform.

[0034] For example, taking the case of forward voltage generation as an example, after the drain of MOSFET Q2 and the drain of MOSFET Q5 are turned on and connected to the high-voltage output, the final output contacts the user through the surface electrode, forming a path (defined as forward voltage). Similarly, after the drain of MOSFET Q3 and the drain of MOSFET Q4 are turned on and connected to the high-voltage output, the final output contacts the user through the surface electrode, forming a path (defined as reverse voltage). Therefore, the MCU can control the on and off of Q2, Q4, Q3 and Q5 by controlling signals SW1, SW2, SW3 and SW4, so that the H-bridge circuit generates a pulse signal with a curved envelope. For example, when Q2 and Q5 are turned on and Q3 and Q4 are turned off, the current flows through the load in the forward direction. When Q3 and Q4 are turned on and Q2 and Q5 are turned off, the current flows through the load in the reverse direction. According to this principle, different waveforms can be generated by repeatedly controlling the on and off.

[0035] Based on this, in an optional embodiment of the present application, the electrical stimulator includes: an electrical stimulation signal generating module; the electrical stimulation signal generating module includes: a constant current module, a microcontroller MCU and an H-bridge circuit; wherein,

[0036] The constant current module is connected to the H-bridge circuit and is used to provide current to the H-bridge circuit;

[0037] The MCU is connected to the H-bridge circuit and is used to send a control signal to the H-bridge circuit, where the control signal is used to control the H-bridge circuit to generate the electrical stimulation signal.

[0038] In an optional embodiment of the present application, the electrical stimulation signal generating module further includes: a sampling module;

[0039] The sampling module is connected to the H-bridge circuit and the MCU, and is used to collect the operating parameters of the H-bridge circuit, obtain a sampling signal, and send the sampling signal to the MCU;

[0040] The MCU is used to receive the sampling signal and adjust the control signal according to the sampling signal.

[0041] Here, the operating parameters of the H-bridge circuit include: current and / or voltage.

[0042] refer to Figure 6 , Figure 6 This is a schematic diagram of the structure of the boost module provided in the embodiment of the present application, as shown in FIG. Figure 6As shown, in this embodiment, the boost module includes: a boost power supply VBAT, a transformer Lp, a capacitor C1, an inductor U1, a diode D2, a diode D1, a transistor Q1, a PWM power supply, a diode D3, an electrolytic capacitor C2 and a capacitor U2, wherein one end of U2, C2 and D3 is connected to the H-bridge circuit in the electrical stimulation signal generating module to provide the electrical stimulation signal generating module with the voltage required to generate the electrical stimulation signal, thereby enhancing the strength of the electrical stimulation signal.

[0043] Based on this, in an embodiment of the present application, the electrical stimulator further includes a boost module, which is connected to the electrical stimulation signal generating module to enhance the strength of the electrical stimulation signal.

[0044] Example 2

[0045] refer to Figure 7 , Figure 7 Schematic diagram of the structure of the electrical stimulation signal generating module provided in the embodiment of the present application Figure 2 In this embodiment, the electrical stimulation signal generating module includes: a pulse signal generating module, an envelope signal generating module and a modulation module; the pulse signal generating module is connected to the modulation module, and the envelope signal generating module is connected to the modulation module;

[0046] The pulse signal generating module is used to generate a pulse signal and send the pulse signal to the modulation module;

[0047] The envelope signal generating module is used to generate a curve envelope signal and send the curve envelope signal to the modulation module;

[0048] The modulation module is used to receive the pulse signal and the curve envelope signal, modulate the pulse signal and the curve envelope signal, and generate an electrical stimulation signal; the electrical stimulation signal is a pulse signal with a curve envelope.

[0049] In an embodiment of the present application, the pulse signal includes: a matrix pulse signal.

[0050] In actual application, the therapeutic effect of tibial nerve electrical stimulation using matrix pulse signal is better.

[0051] In the embodiment of the present application, the curve envelope signal includes one or more of the following: a sine envelope signal and a cosine envelope signal. In practical applications, other curve envelope signals may also be used, and the embodiment of the present application does not limit this.

[0052] Exemplary, reference Figure 2 In the embodiment of the present application, the period of the pulse signal is 50ms, and the width of a single pulse is 200us.

[0053] For example, taking the pulse signal as a matrix pulse signal and the envelope signal as a sinusoidal envelope signal as an example, the frequency of the matrix pulse signal is 20 Hz, the period is 50 ms, and the pulse width is 200 μs. The pulse signal can be represented by a unit pulse function, such as: Where T is the period, τ is the pulse width, and the square wave signal s(t) can be expressed as: The frequency of the sinusoidal envelope signal is 2 Hz, and its period is 0.5 seconds. The sinusoidal envelope signal can be expressed as: e(t) = Asin(2πft) = Asin(4πt), where f corresponds to the frequency of 2 Hz, A is the amplitude of the envelope, and t is time. The modulated signal m(t) is the mathematical product of the square wave array s(t) and the sinusoidal envelope e(t), specifically expressed as:

[0054] refer to Figure 8 , Figure 8 Schematic diagram of the electrical stimulation signal provided in the embodiment of the present application Figure 2 , Figure 8 The electrical stimulation signal shown in is a matrix pulse signal modulated by a sinusoidal envelope signal.

[0055] The curve envelope signal can be a periodic signal, and a lower frequency can allow the user to feel a more obvious change in the intensity of the electrical stimulation. Based on this, in the embodiment of the present application, the curve envelope signal is a periodic curve envelope signal, and the frequency of the curve envelope signal is less than or equal to 2Hz.

[0056] The pulse signal generating module includes one or more of the following: a pulse signal generating circuit, a phase-locked loop (PLL), and a function generating circuit.

[0057] Exemplarily, the pulse signal generating circuit includes: a crystal oscillator circuit, a timer chip, and an MCU; the crystal oscillator in the crystal oscillator circuit generates a stable high-frequency oscillation signal as a reference clock signal through the piezoelectric effect, and the corresponding MCU is configured in a steady-state multivibrator mode, and a corresponding pulse signal is generated by installing corresponding external resistors and capacitors on the circuit; Exemplarily, a PLL circuit is used to generate a stable pulse sequence to obtain a pulse signal; Exemplarily, in the function generating circuit, a point-by-point method is used to draw the function value point by point to generate a pulse sequence, and the amplitude is calculated and stored at a specific time point, and then these amplitudes are read and output point by point at the output. For a periodic pulse signal, all points within a period are pre-calculated and stored, and then these points are output cyclically to obtain a pulse signal.

[0058] Based on this, in an optional implementation of the present application, the pulse signal generating circuit includes: a crystal oscillator circuit, a timer chip and an MCU.

[0059] In actual applications, other methods may also be used to generate pulse signals, and the embodiments of the present application do not limit this.

[0060] In an embodiment of the present application, the envelope signal generating module includes one or more of the following: an oscillator circuit, a microcontroller unit (MCU), a direct digital synthesizer (DDS), a phase-locked loop (PLL), and a function generating circuit.

[0061] Here, taking the curve envelope signal as a sine wave as an example, the oscillator circuit can specifically be an RC oscillator circuit, corresponding to an oscillator circuit of a resistor and capacitor. When the capacitor is charged through the resistor, the capacitor voltage increases over time. Conversely, when the capacitor is discharged through the resistor, the internal voltage of the capacitor decreases. By controlling the charging and discharging timing, the output of the sine wave is achieved. The MCU can pre-calculate the sample points of the sine waveform, store these sample points in an array, use a timer to output these sample points at regular intervals, and output the analog signal through a DAC. After calculating the sample points, the MCU can also output a duty cycle modulated signal through PWM, and then convert the PWM signal into an analog sine wave signal through a low-pass filter. The DDSIC generates a precise sine wave envelope signal through a lookup table and a digital-to-analog converter (DAC). A PLL circuit is used to generate a sine wave envelope signal synchronized with the pulse signal. In the function generation circuit, the waveform is generated by plotting the function value point by point using the point-by-point method. The amplitude of the waveform is calculated and stored at specific time points, and then read and output these amplitudes point by point during output. For a periodic sine wave, all points within a period are pre-calculated and stored, and then these points are cyclically output to obtain a sine wave envelope signal.

[0062] In actual applications, other methods may also be used to generate the curve envelope signal, and the embodiments of the present application do not limit this.

[0063] In practical applications, since the pulse matrix has a specific output frequency, an analog switch is required to control the on and off of the pulse signal, and a sine wave signal controls the on-time of the switch. Only during the on-time can the corresponding modulation signal enter the modulation module.

[0064] In an embodiment of the present application, the modulation module includes: an analog multiplier chip.

[0065] The analog multiplier chip includes: a first input end, a second input end and a first output end; the first input end is connected to the pulse signal generating module, for receiving the pulse signal connected and sent by the pulse signal generating module; the second input end is connected to the envelope signal generating module, for receiving the curve envelope signal connected and sent by the envelope signal generating module; the first output end is used to output an electrical stimulation signal with a curve envelope.

[0066] The modulation module can be implemented using an analog multiplier chip, which multiplies a pulse signal and a curve envelope signal to achieve amplitude modulation. For example, the AD633 multiplier chip can be used. Its main function is achieved through multiple internal operational amplifiers and a resistor network. The connection method of the power amplifier determines the operation rules of the input signal (such as multiplying two signals, or more input signals). The resistor network is used to set the weighting and adjustment of the input signal to achieve multiplication. The output signal of the multiplier chip is a pulse signal with a sine wave envelope.

[0067] In actual applications, the modulation module may also adopt other circuits, and the embodiments of the present application do not limit this.

[0068] Reference to the examples in this application Figure 9 , Figure 9 This is a structural diagram of the electrical stimulator provided in an embodiment of the present application, wherein the electrical stimulator further includes a boost module; the boost module is connected to the modulation module in the electrical stimulation signal generating module, and the boost module is used to enhance the strength of the electrical stimulation signal.

[0069] After the modulation module generates the envelope stimulation signal, the signal strength is increased by the boost module to achieve the stimulation level of transcutaneous electrical stimulation. Exemplarily, the boost module can adopt a boost converter.

[0070] Exemplarily, the circuit of a boost converter includes the following key components: a boost power supply, a switching element, a diode, an energy storage inductor, and a capacitor.

[0071] For example, the switching element may be a MOSFET, which is mainly responsible for periodically switching the current on and off, and regulating the transfer of energy by controlling the opening and closing of the switch. The specific process is as follows: the MOSFET is turned on, the input power supply voltage flows through the inductor, the current in the inductor gradually increases, and the energy stored in the inductor increases. At this time, the current cannot flow to the output end because the diode is reverse biased. During the discharge process, the MOSFET is turned off, and the current in the inductor cannot continue to flow to the MOSFET, so the current in the inductor flows to the output capacitor through the diode. The energy stored in the inductor is released, pushing the voltage in the capacitor to increase, thereby achieving a boost conversion. At the same time, in order to achieve a stable boost, the switching frequency and duty cycle of the MOSFET can also be adjusted through a feedback circuit.

[0072] The tibial nerve electrical stimulation system provided in the embodiment of the present application generates an electrical stimulation signal with high-resolution change levels. Each patient has different tolerance to stimulation intensity. The high-resolution level change can more accurately adjust to the optimal treatment intensity suitable for the individual, providing a personalized and comfortable treatment experience. The tibial nerve electrical stimulation system provided in the embodiment of the present application can gradually increase or decrease the stimulation intensity with a higher resolution within the same change amplitude. The step-by-step and smooth intensity change can significantly reduce the discomfort caused by sudden changes, allowing patients to adapt to each change more easily without feeling sudden strong tingling, reducing patients' resistance during treatment and increasing tolerance to the therapy.

[0073] The tibial nerve electrical stimulation system provided in the embodiment of the present application has an electrode placed on the tibial nerve stimulation point on the user's skin. The electrode is connected to the electrical stimulator through a wire, and is used to apply the electrical stimulation signal generated by the electrical stimulator to the corresponding stimulation point for electrical stimulation treatment.

[0074] In the several embodiments provided in this application, it should be understood that the disclosed systems and devices can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0075] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0076] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A tibial nerve electrical stimulation system, comprising: An electrical stimulator and an electrode sheet; the electrical stimulator is connected to the electrode sheet; wherein, The electrical stimulator is used to generate an electrical stimulation signal and transmit the electrical stimulation signal to the electrode sheet; the electrical stimulation signal is a pulse signal with a curved envelope; The electrode sheet is connected to the human body and is used to receive the electrical stimulation signal sent by the electrical stimulator and transmit the electrical stimulation signal to the tibial nerve.

2. The tibial nerve electrical stimulation system according to claim 1, wherein: The electrical stimulator includes: an electrical stimulation signal generating module; the electrical stimulation signal generating module includes: a constant current module, a microcontroller MCU and an H-bridge circuit; wherein, The constant current module is connected to the H-bridge circuit and is used to provide current to the H-bridge circuit; The MCU is connected to the H-bridge circuit and is used to send a control signal to the H-bridge circuit, where the control signal is used to control the H-bridge circuit to generate the electrical stimulation signal.

3. The tibial nerve electrical stimulation system according to claim 2, wherein: The electrical stimulation signal generating module further includes: a sampling module; The sampling module is connected to the H-bridge circuit and the MCU, and is used to collect the operating parameters of the H-bridge circuit, obtain a sampling signal, and send the sampling signal to the MCU; The MCU is used to receive the sampling signal and adjust the control signal according to the sampling signal.

4. The tibial nerve electrical stimulation system according to claim 1, wherein: The electrical stimulator includes: an electrical stimulation signal generating module; the electrical stimulation signal generating module includes: a pulse signal generating module, an envelope signal generating module and a modulation module; the pulse signal generating module is connected to the modulation module, and the envelope signal generating module is connected to the modulation module; The pulse signal generating module is used to generate a pulse signal and send the pulse signal to the modulation module; The envelope signal generating module is used to generate a curve envelope signal and send the curve envelope signal to the modulation module; The modulation module is used to receive the pulse signal and the curve envelope signal, modulate the pulse signal and the curve envelope signal, and generate the electrical stimulation signal.

5. The tibial nerve electrical stimulation system according to claim 4, characterized in that: The curve envelope signal includes one or more of the following: a sine envelope signal and a cosine envelope signal.

6. The tibial nerve electrical stimulation system according to claim 4, characterized in that: The envelope signal generating module includes one or more of the following: an oscillator circuit, an MCU, a direct digital synthesizer DDS, a phase-locked loop PLL, and a function generating circuit.

7. The tibial nerve electrical stimulation system according to claim 4, characterized in that: The pulse signal generating module includes one or more of the following: a pulse signal generating circuit, a phase-locked loop (PLL), and a function generating circuit.

8. The tibial nerve electrical stimulation system according to claim 4, wherein: The modulation module includes: an analog multiplier chip.

9. The tibial nerve electrical stimulation system according to any one of claims 2 to 8, characterized in that: The electrical stimulator further comprises: a boost module; The boost module is connected to the electrical stimulation signal generating module and is used to enhance the strength of the electrical stimulation signal.

10. The tibial nerve electrical stimulation system according to claim 9, characterized in that: The boost module includes: a boost power supply, a switch, a diode, a capacitor and an inductor.

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