Tunable constant-current intrusive electrocoagulation equipment

Abstract

The invention discloses a tunable constant-current intrusive electrocoagulation device which comprises a display screen, a current adjusting button, a tunable constant-current electrocoagulation device, an intrusive medical guide wire interface and a medical guide wire, and the tunable constant-current electrocoagulation device comprises a battery, a power module, a high-frequency arbitrary waveform generation module and a constant-current output module. The high-frequency arbitrary waveform generation module comprises a digital control module and a frequency synthesis module, and the constant current output module comprises a current sampling circuit and a constant current module. The amplitude and frequency of the output waveform are flexibly configured through the microcontroller, the high-frequency alternating current of 1-37.5 MHz can be tuned and output, the weak alternating current constant current output of 0-3mA is realized, the stepping range of 100 [mu] A is met, the capacity of outputting the constant-current alternating current of the electrocoagulation equipment is expanded, the stepping precision of the output weak current is improved, and the stability of the electrocoagulation equipment is improved. Neural reflex reaction caused by electrocoagulation treatment on cerebrovascular diseases by direct current signals in a traditional electrocoagulation treatment scheme is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of medical electronic equipment, and in particular relates to a tunable constant current interventional electrocoagulation device. Background Art

[0002] Intravascular electrocoagulation is a method of passing an electric current through a metal device inserted into an artery or aneurysm cavity, simulating the reversal of the vascular endothelial potential to adsorb negatively charged blood components, thereby forming a local thrombus and occluding the blood vessel and aneurysm cavity.

[0003] At present, the commonly used intravascular interventional treatment in clinical practice adopts simple coil embolization, balloon / stent assisted coil embolization and covered stent / blood guide device placement, which have high consumables and cannot effectively treat small blood vessels. Compared with traditional treatment options, micro-guidewire electrocoagulation treatment is simpler to operate, more cost-effective and can treat small blood vessels.

[0004] Existing micro-guidewire electrocoagulation treatment programs are mainly concentrated in laboratory research, using weak direct current for electrocoagulation treatment. The electrocoagulation equipment used in the research cannot support real-time adjustment of current frequency and intensity, and it is difficult to provide high-frequency alternating current. On the one hand, the integrity of the experiment is limited, and on the other hand, direct current will cause the animal's nerve reflex reaction, resulting in experimental failure. Therefore, there is an urgent need for an interventional electrocoagulation device that is flexible and portable and can generate frequency-tunable and intensity-controllable alternating current to meet the needs of experimental research. Summary of the invention

[0005] In view of this, the present invention aims to overcome the deficiencies of the above-mentioned problems in the prior art and proposes a tunable constant current interventional electrocoagulation device.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] The first aspect of the present invention provides a tunable constant current electrocoagulation device, which can tunably output a high frequency alternating current of 1 to 37.5 MHz, realize a weak alternating current constant current output of 0 to 3 mA, and meet a step range of 100 μA.

[0008] A second aspect of the present invention provides a tunable constant current interventional electrocoagulation device, comprising the above-mentioned tunable constant current electrocoagulation device, an interventional medical guidewire interface and a medical guidewire;

[0009] The tunable constant current electrocoagulation device comprises a battery, a power module, a high-frequency arbitrary waveform generation module, and a constant current output module, wherein the battery is connected to the power module, the power module is respectively connected to the high-frequency arbitrary waveform generation module and the constant current output module, and the high-frequency arbitrary waveform generation module is connected to the constant current output module; the interventional medical guide wire interface is used to connect the constant current output module and the medical guide wire;

[0010] The high-frequency arbitrary waveform generation module includes a digital control module and a frequency synthesis module, and the digital control module is connected to the frequency synthesis module; the digital control module includes a microcontroller, and the frequency synthesis module includes a DDS circuit, a filter circuit and a feedback amplifier circuit, and the DDS circuit is connected to the filter circuit, and the filter circuit is connected to the feedback amplifier circuit;

[0011] The constant current output module includes a current sampling circuit and a constant current module;

[0012] The medical guide wire is used as a carrier of electric current to puncture into a patient's blood vessel.

[0013] Further, the power module includes a voltage conversion circuit, and the voltage conversion circuit is used to convert the battery voltage into a target voltage of other modules;

[0014] The voltage conversion circuit includes multiple power rails, namely a first power rail, a second power rail, a third power rail, a fourth power rail and a fifth power rail, which respectively generate +15V, +5V, +12V, -15V and -12V voltages required by the target module;

[0015] The first power rail input is powered by a battery and generates a +15V voltage through a DC step-down circuit;

[0016] The input voltage of the second power rail is the output voltage of the first power rail, and the input voltage is converted into a +5V voltage by a step-down circuit;

[0017] The input voltage of the third power rail is the output voltage of the first power rail, and the input voltage is converted into a +12V voltage by a step-down circuit;

[0018] The fourth power rail voltage input is the voltage output of the second power rail, and the input voltage is converted into a -15V output through a polarity reversal circuit;

[0019] The fifth power rail voltage input is the voltage output of the fourth power rail, and the input voltage is converted into a -12V output through a step-down circuit.

[0020] Furthermore, it also includes a display screen and a current adjustment button, the display screen adopts a TFT display screen, the display screen is connected to a digital control module, and the current adjustment button is connected to the digital control module.

[0021] Furthermore, the microcontroller is used to communicate with the frequency synthesis module to control the output waveform, signal frequency and signal amplitude of the frequency synthesis module.

[0022] Furthermore, the DDS circuit controls the output of an analog signal with adjustable frequency amplitude through a digital signal, and the signal is used to control the output AC frequency to be adjustable between 1 and 37.5 MHz. The filter circuit is used for high-frequency filtering, and the feedback amplifier circuit uses co-directional amplification to adjust the output signal amplitude.

[0023] Furthermore, the filtering circuit adopts a sixth-order passive Butterworth LC low-pass filter.

[0024] Furthermore, the current sampling circuit is used to detect the output current, convert the output current into a voltage value and send it to the digital control module.

[0025] Furthermore, the constant current module is used to generate alternating current constant current electricity.

[0026] Furthermore, when the digital control module configures the frequency synthesis module to output an AC signal, the constant current module can output a weak AC current in the range of 0 to 3 mA with a step accuracy of 100 μA.

[0027] Compared with the prior art, the tunable constant current interventional electrocoagulation device described in the present invention has the following advantages:

[0028] The interventional electrocoagulation device of the present invention adopts a modular circuit structure and is small in size and easy to carry.

[0029] In view of the drawback that batteries are used as electrocoagulation equipment in existing experimental research and thus the current frequency and intensity cannot be adjusted, the present invention utilizes a high-frequency arbitrary waveform generation module and a constant current output module to adjust the frequency and intensity of the output current in real time, thereby improving the flexibility and precision of the electrocoagulation equipment and compensating for the defect of insufficient experimental data due to equipment limitations.

[0030] The present invention flexibly configures the amplitude and frequency of the output waveform through a microcontroller, can tune and output high-frequency alternating current of 1 to 37.5 MHz, achieves a constant-current output of weak alternating current of 0 to 3 mA, meets a step range of 100 μA, expands the ability of the electrocoagulation equipment to output constant-current alternating current, improves the step accuracy of the output weak current, and avoids the nerve reflex reaction caused by the direct current signal in the traditional electrocoagulation treatment scheme when performing electrocoagulation treatment on cerebral hemangioma diseases. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 A diagram of the architecture of a tunable constant current interventional electrocoagulation device provided for this embodiment.

[0033] Figure 2 A block diagram of a multi-power rail architecture of a tunable constant current interventional electrocoagulation device provided in this embodiment.

[0034] Figure 3 A circuit structure diagram of a power supply module of a tunable constant current interventional electrocoagulation device provided in this embodiment.

[0035] Figure 4 A circuit structure diagram of a digital control module of a tunable constant current interventional electrocoagulation device provided in this embodiment.

[0036] Figure 5 A circuit structure diagram of a frequency synthesis module of a tunable constant current interventional electrocoagulation device provided in this embodiment.

[0037] Figure 6 A circuit structure diagram of current sampling for a tunable constant current interventional electrocoagulation device provided in this embodiment.

[0038] Figure 7 A circuit structure diagram of a constant current module of a tunable constant current interventional electrocoagulation device provided in this embodiment. DETAILED DESCRIPTION

[0039] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0040] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0041] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0042] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0043] In one embodiment, Figure 1 As shown, a schematic diagram of the architecture of a tunable constant-current interventional electrocoagulation device is provided, including a display screen, a current adjustment button, a tunable constant-current electrocoagulation device, an interventional medical guidewire interface and a medical guidewire. The display screen adopts a TFT display screen, and the current adjustment button is a mechanical button. The interventional electrocoagulation device mainly includes a battery, a power module, a high-frequency arbitrary waveform generation module, a constant current output module, an interventional medical guidewire interface and a medical guidewire.

[0044] In the above embodiment, the display screen adopts a conventional TFT display screen, the current adjustment button adopts a mechanical button, and the battery adopts a conventional instrument dry cell connected in series to the power module, and the power module converts the battery voltage into power for the high-frequency arbitrary generation module and the constant current output module. The high-frequency arbitrary waveform generation module includes a digital control module and a frequency synthesis module. The digital control module includes a microcontroller chip for controlling the output waveform, signal frequency and signal amplitude of the frequency synthesis module; the frequency synthesis module includes a DDS circuit, a filter circuit and a feedback amplifier circuit. The DDS circuit can control the output frequency amplitude of the adjustable analog signal through a digital signal, the filter circuit is used for high-frequency filtering, and the feedback amplifier circuit adopts the same direction amplification for adjusting the output signal amplitude. The constant current output module includes a current sampling circuit and a constant current module. The current sampling is used to detect the output current size, convert the output current into a voltage value and send it to the digital control module, and the constant current module is used to generate weak AC and DC. The invasive medical guide wire interface is used to connect the constant current output module and the medical guide wire. The medical guide wire is used as a carrier of current to puncture into the patient's blood vessels.

[0045] In one embodiment, Figure 2 The first power rail input is powered by a battery. Figure 3The power module shown converts the battery voltage into the voltage required by each module in the device. The battery voltage is connected to the chip input pin of U25 after capacitor filtering, and the input voltage is output +15V through the DC-DC step-down circuit. The input voltage of the second power rail is the output voltage of the first power rail, positive 15V, and the +15V voltage is connected to the chip input pin of U9 to generate a +5V voltage. The input voltage of the third power rail is the output voltage of the first power rail, +15V is connected to the chip input pin of U30, and converted to +12V voltage through the step-down circuit. The voltage input of the fourth power rail is the voltage output of the second power rail, and the +5V voltage is connected to the chip input pin of U26. By adjusting the resistance ratio of the feedback circuit, the theoretical output voltage value is calculated, and the +5V is converted to -15V output through the polarity reversal circuit. The voltage input of the fifth power rail is the voltage output of the fourth power rail, -15V is connected to the input pin of the U29 chip, and converted to -12V output through the step-down circuit.

[0046] The power module of the present invention is designed to adapt to the voltage standards of subsequent different modules. In order to generate the positive and negative voltage values ​​required by the high-frequency arbitrary waveform generation module and the constant current output module, a positive power supply input method is adopted in this embodiment, and the required positive and negative voltage values ​​are obtained through multi-stage power rails. The unipolar power supply effectively improves the portability and flexibility of the device.

[0047] In one embodiment, Figure 4 The digital control module shown in the figure includes a microcontroller chip, which is used to configure the output waveform, signal frequency and signal amplitude of the frequency synthesis module. The microcontroller in the digital control module provides two configuration methods for configuring the frequency synthesis module. The first method is to modify it in real time through the host computer, and the second method is to solidify the configuration information in the internal storage device and modify it manually through the current adjustment button.

[0048] In one embodiment, Figure 5 The frequency synthesis module shown includes a DDS circuit, a filter circuit and a feedback amplifier circuit. The DDS circuit can control the output of an analog signal with adjustable frequency amplitude through a digital signal. The filter circuit is used for high-frequency filtering. The feedback amplifier circuit uses the same-direction amplification to adjust the output signal amplitude.

[0049] In the above embodiment, the DDS circuit builds a peripheral circuit around U11, and the DDS chip pin 1 is connected to the DAC output pin of the microcontroller through a series resistor R132. The microcontroller changes the output current of U11 by changing the DAC output voltage. Pin 8 of the DDS chip is connected to the clock output pin of the U12 crystal oscillator. U12 is an active crystal oscillator that provides an external reference clock for the DDS chip. Pins 12 to 16 are the serial protocol data ports of the DDS chip, which are connected to the microcontroller to configure the DDS chip. Pins 19 and 20 are the output pins of the DDS chip, which are connected to the feedback amplifier circuit through the filter circuit and then to the connector.

[0050] In the previous embodiment, the filtering circuit is used to perform low-pass filtering on the output signal of the DDS chip. A sixth-order passive Butterworth LC low-pass filter composed of resistors and inductors is used to filter the high-order noise on the output signal. The feedback amplifier circuit is used to adjust the amplitude of the output signal of the DDS chip. The output signal of the DDS chip is limited by the chip itself and cannot adapt to the input voltage range of the constant current output module. Using the in-phase amplification structure of the feedback amplifier circuit, the positive input end of the amplifier is connected to the signal output end of the DDS chip, and the 0.6V voltage output by the pin 2 of the DDS chip is used as the reference voltage for feedback. The voltage of the pin 1 of the DDS chip is changed by the digital control module, and the voltage range of the output signal of the feedback amplifier circuit is changed, which is used for signal conditioning to provide a suitable signal amplitude for the constant current output module.

[0051] In one embodiment, Figure 6 The current sampling circuit shown is used to detect the output current and convert the output current into a voltage value and send it to the digital control module. The current sampling circuit consists of a precision sampling resistor and a current sensing amplifier. Resistor R7 is a precision sampling resistor. The two ends of resistor R7 are respectively connected to the positive and negative input pins of the current sensing amplifier U4. The current passes through the two ends of the sampling resistor to form a voltage difference. The current sensing amplifier collects the voltage difference across the resistor and sends the collected information to the digital control module through the serial port protocol. The data control module calculates the sampled information and transmits the calculation results to the display screen for display.

[0052] In one embodiment, Figure 7 The constant current module shown can be used to generate both AC constant current and DC constant current. Figure 7 In the figure, the input signal is input to the negative input terminal of the operational amplifier U2 through the H3 connector in series with resistors R6 and R3. The operational amplifier U3 acts as a follower, and the pin 6 of U2 outputs AC and DC signals that are connected to the H4 connector through resistor R2.

[0053] In the above embodiments, in order to better demonstrate the frequency tuning and intensity control of high-frequency alternating current by the present invention, the tuning process and current step control will be further described.

[0054] The frequency tuning process of high-frequency alternating current is as follows: Figure 4 The digital control module shown is configured via the SPI serial port protocol on pins PA5 to 7. Figure 5 The register value of the DDS chip in the DDS chip is configured with different register values ​​to make the DDS chip output a high-frequency AC signal of 1 to 37.5 MHz. The high-frequency AC signal output by the DDS chip is connected to the socket CN3 through Figure 7 The socket H3 is connected to the negative input terminal of the operational amplifier U2 through resistors R6 and R3. The high-frequency AC signal passes through the two-stage negative feedback amplifier circuit of U2 and U3, and outputs a high-frequency AC of 1 to 37.5MHz from pin 6 of U2.

[0055] The AC current intensity and step control are as follows: Figure 4 The digital control module shown adjusts the voltage value of the internal DAC output of the PA4 pin by changing the internal register value. This signal is connected to Figure 5 One side of the middle resistor R132. Figure 5 The pin 19 of the DDS outputs an AC signal. The voltage value output by the DAC controls the swing of the AC signal between 0 and 0.6V. The AC signal output by the DDS is amplified to between 0 and 1.2V through the feedback amplifier circuit of U14. Figure 7 The constant current module circuit shown in the figure obtains a weak AC current of 0 to 3 mA, which is the ratio of the AC signal swing to the resistor R2. At this time, the accuracy of the internal DAC is 12 bits, the swing range is 0.6V, and the output step accuracy of the AC current is 0.6 / 2 12 , about 100μA.

[0056] The present invention can also change the output mode of AC and DC power, which is achieved through the following control: the configuration information of the frequency synthesis module controls the frequency synthesis module to output an AC signal, the constant current module follows the output AC current, and the AC current intensity is controlled by the resistor R2 and the input voltage; the digital control module changes the configuration information of the frequency synthesis module, controls the frequency synthesis module to output a DC signal, the constant current module follows the output DC current, and the DC current intensity is controlled by the resistor R2 and the input voltage.

[0057] In one embodiment, the medical guidewire interface includes a return interface and a four-core Lemo connector, one end of the Lemo connector is connected to the output current interface of the constant current output module, and the other end is connected to the medical guidewire. The return interface is connected to another medical guidewire using a copper wire and a clip for the loop path of the current. The medical guidewire is made of titanium alloy, with a tip diameter of 0.4mm and a rear section diameter of 0.7mm. When in use, the medical guidewire is used as a carrier of current to puncture into the patient's blood vessels.

[0058] In the electrocoagulation treatment experiment on the blood vessels of mice, the device of the present application was used to apply high-frequency weak alternating current of 1MHz~1mA, 17.5MHz~1.5mA, 37.5MHz~2.5mA, and high-frequency weak direct current of 1MHz~1mA, 17.5MHz~1.5mA, 37.5MHz~2.5mA, respectively. It was found that regardless of the AC or DC conditions, the current intensity would only affect the speed of electrocoagulation to form thrombi, and when direct current was applied, the experimental mice had a slight or obvious knee jerk reflex reaction, while when alternating current was applied, there was no reaction. It can be seen that the device of the present application can tunably output high-frequency weak alternating current of 1~37.5MHz and 0~3mA, which can avoid the nerve reflex reaction caused by the direct current signal in the traditional electrocoagulation treatment scheme when electrocoagulating cerebral hemangioma diseases.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A tunable constant current electrocoagulation device, characterized in that: The high-frequency AC output can be tuned to 1 to 37.5 MHz, achieving a weak AC constant current output of 0 to 3 mA, meeting a step range of 100 μA.

2. A tunable constant current interventional electrocoagulation device, characterized in that: It comprises the tunable constant current electrocoagulation device, the interventional medical guidewire interface and the medical guidewire as described in claim 1; The tunable constant current electrocoagulation device comprises a battery, a power module, a high-frequency arbitrary waveform generation module, and a constant current output module, wherein the battery is connected to the power module, the power module is respectively connected to the high-frequency arbitrary waveform generation module and the constant current output module, and the high-frequency arbitrary waveform generation module is connected to the constant current output module; the interventional medical guide wire interface is used to connect the constant current output module and the medical guide wire; The high-frequency arbitrary waveform generation module includes a digital control module and a frequency synthesis module, and the digital control module is connected to the frequency synthesis module; the digital control module includes a microcontroller, and the frequency synthesis module includes a DDS circuit, a filter circuit and a feedback amplifier circuit, and the DDS circuit is connected to the filter circuit, and the filter circuit is connected to the feedback amplifier circuit; The constant current output module includes a current sampling circuit and a constant current module; The medical guide wire is used as a carrier of electric current to puncture into a patient's blood vessel.

3. The tunable constant current interventional electrocoagulation device according to claim 2, characterized in that: The power module includes a voltage conversion circuit, which is used to convert the battery voltage into a target voltage of other modules; The voltage conversion circuit includes multiple power rails, namely a first power rail, a second power rail, a third power rail, a fourth power rail and a fifth power rail, which respectively generate +15V, +5V, +12V, -15V and -12V voltages required by the target module; The first power rail input is powered by a battery and generates a +15V voltage through a DC step-down circuit; The input voltage of the second power rail is the output voltage of the first power rail, and the input voltage is converted into a +5V voltage by a step-down circuit; The input voltage of the third power rail is the output voltage of the first power rail, and the input voltage is converted into a +12V voltage by a step-down circuit; The fourth power rail voltage input is the voltage output of the second power rail, and the input voltage is converted into a -15V output through a polarity reversal circuit; The fifth power rail voltage input is the voltage output of the fourth power rail, and the input voltage is converted into a -12V output through a step-down circuit.

4. The tunable constant current interventional electrocoagulation device according to claim 2, characterized in that: It also includes a display screen and a current adjustment button. The display screen adopts a TFT display screen. The display screen is connected to a digital control module. The current adjustment button is connected to the digital control module.

5. The tunable constant current interventional electrocoagulation device according to claim 2, characterized in that: The microcontroller is used to communicate with the frequency synthesis module and control the output waveform, signal frequency and signal amplitude of the frequency synthesis module.

6. The tunable constant current interventional electrocoagulation device according to claim 2, characterized in that: The DDS circuit controls the output of an analog signal with adjustable frequency and amplitude through a digital signal, the filter circuit is used for high-frequency filtering, and the feedback amplifier circuit uses co-directional amplification to adjust the output signal amplitude.

7. The tunable constant current interventional electrocoagulation device according to claim 6, characterized in that: The filtering circuit adopts a sixth-order passive Butterworth LC low-pass filter.

8. The tunable constant current interventional electrocoagulation device according to claim 2, characterized in that: The current sampling circuit is used to detect the output current, convert the output current into a voltage value and send it to the digital control module.

9. The tunable constant current interventional electrocoagulation device according to claim 2, characterized in that: The constant current module is used to generate alternating current constant current electricity.

10. The tunable constant current interventional electrocoagulation device according to claim 2, characterized in that: When the digital control module configures the frequency synthesis module to output an AC signal, the constant current module outputs a weak AC current.

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