Dynamic test method and system for frequency domain impedance characteristic of tissue

Abstract

The invention discloses a dynamic test method and system for tissue frequency domain impedance characteristics, and belongs to the technical field of medical detection. The system comprises an energy generator, a bipolar scalpel, a signal generator, a radio frequency power amplifier module, a control unit, two loop switches, a sampling probe and a test unit. An electrode of the bipolar scalpel is used for being in contact with a biological tissue to be subjected to frequency domain impedance characteristic testing; the energy generator is connected with the first loop switch and is used for outputting an electric resection / electrocoagulation signal to the biological tissue so as to dynamically reproduce the state change of the biological tissue; and the signal generator inputs a broadband excitation voltage signal to the biological tissue through the radio frequency power amplifier module and the second loop switch. The control unit is used for coordinating on-off of the two loop switches. The sampling probe is used for collecting voltage and current signals of the double electrodes in real time and feeding back the signals to the testing unit. The test unit generates a real-time impedance characteristic spectrogram of the biological tissue along with frequency change. The tissue impedance change can be monitored on line in real time.

Description

Technical Field

[0001] This invention belongs to the field of medical testing technology, specifically relating to a dynamic testing method and system for tissue frequency domain impedance characteristics. Background Technology

[0002] Electrosurgical instruments encompass various categories, including high-frequency electrosurgical units, plasma scalpels, and large vessel closure instruments, and are among the most widely used basic medical equipment in modern surgery. An electrosurgical instrument consists of an energy generator (power source) and a scalpel electrode (actuator). Its working principle involves the energy generator converting mains frequency alternating current into high-frequency alternating current, which is then transmitted to the biological tissue via the scalpel electrode. Surgical operations such as cutting, coagulation, vaporization, or ablation of the biological tissue are performed using the thermal effect of the current or the plasma effect. Therefore, the biological tissue is both the target of the electrosurgical instrument and the external load of the energy generator. From an electrical perspective, the impedance characteristics of the biological tissue directly affect the operation of the energy generator. To develop advanced energy surgical equipment, it is necessary to accurately measure the impedance characteristics of biological tissue.

[0003] However, existing studies on the impedance characteristics of biological tissues mostly use spectrum analyzers or multi-electrode methods such as three-point and four-point methods to test the impedance characteristics of tissues. These tests cannot simulate the dynamic processes such as tissue temperature rise and compression temperature rise caused by surgical procedures such as electrocautery and electrocoagulation, and they also ignore the impact of these processes on impedance, thus failing to reflect the true impedance characteristics of biological tissues during surgical procedures. Summary of the Invention

[0004] To address the problems in the prior art, this invention provides a dynamic testing method and system for the frequency domain impedance characteristics of an organization.

[0005] The technical solution of the present invention is as follows: In a first aspect, the present invention discloses a dynamic testing system for the frequency domain impedance characteristics of tissue, comprising an energy generator, a bipolar scalpel, a signal generator, a radio frequency power amplifier module, a control unit, a dual-channel control module, a sampling probe, and a testing unit; the bipolar scalpel has bipolar surgical electrodes, which are used to contact the biological tissue to be tested for frequency domain impedance characteristics. The dual-channel control module includes a first-loop switch and a second-loop switch; an energy generator is used to output electrocautery / electrocoagulation signals, which are sequentially input into the biological tissue through the first-loop switch and a bipolar surgical electrode, dynamically reproducing the changes in the biological tissue state caused by the electrocautery or electrocoagulation process; a signal generator is used to output a wideband excitation voltage signal to the radio frequency power amplifier module, which amplifies the wideband excitation voltage signal, and the amplified wideband excitation voltage signal is sequentially input into the biological tissue through the second-loop switch and a bipolar surgical electrode. The control unit is used to control the on / off state of the two loop switches; the sampling probe is used to sample the voltage and current signals of the bipolar surgical electrode in real time when the signal generator outputs a wideband excitation voltage signal to the biological tissue, and feeds them back to the test unit; the test unit obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency based on the received voltage and current signals, and completes the frequency domain impedance characteristic test of the biological tissue.

[0006] Furthermore, the testing unit includes an oscilloscope, a lock-in amplifier, and a host computer; When both circuit switches are turned on simultaneously, the sampling probe feeds back the voltage and current signals to the lock-in amplifier. At the same time, the lock-in amplifier also receives the broadband excitation voltage signal and obtains the voltage component amplitude, voltage component phase, current component amplitude, and current component phase at each preset discrete frequency point in the broadband excitation voltage from the voltage and current signals. The results are then output to the host computer. Based on the voltage component amplitude, voltage component phase, current component amplitude, and current component phase at each preset discrete frequency point, the host computer obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency. When the two circuit switches are not turned on at the same time, the sampling probe feeds back the voltage and current signals to the oscilloscope, which then outputs the voltage and current signals to the host computer. The host computer obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency based on the voltage and current signals.

[0007] Furthermore, both the first circuit switch and the second circuit switch include bidirectional switching transistors, which adopt a bidirectional switching structure consisting of two power MOSFETs connected back-to-back in a common source configuration.

[0008] Secondly, the present invention also discloses a dynamic testing method for the organization frequency domain impedance characteristics of the test system, comprising the following steps: When the control unit simultaneously activates both loop switches, the energy generator outputs an electrocautery / coagulation signal. This signal passes sequentially through the first loop switch and the bipolar surgical electrode into the biological tissue, dynamically reproducing the changes in the biological tissue state caused by the electrocautery or coagulation process. Simultaneously, the signal generator outputs a wideband excitation voltage signal to the radio frequency power amplifier module. The module amplifies the signal, and the amplified signal passes sequentially through the second loop switch and the bipolar surgical electrode into the biological tissue. The sampling probe samples the voltage and current signals from the bipolar surgical electrode in real time and feeds them back to the testing unit. Based on the received voltage and current signals, the testing unit obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency, completing the frequency domain impedance characteristic test of the biological tissue. When the control unit controls the two loop switches to not be turned on simultaneously, and the first loop switch is turned on first and then turned off, and the second loop switch is turned off first and then turned off; the energy generator first outputs an electrocautery / coagulation signal to the biological tissue; then the signal generator outputs a wideband excitation voltage signal to the biological tissue, and at the same time the sampling probe samples the voltage and current signals of the bipolar surgical electrode in real time and feeds them back to the testing unit; the testing unit obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency based on the received voltage and current signals.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) This invention, by setting up two independent and controllable signal paths—an energy generator and a signal generator—can alternately or superimpose electrocautery / electrocoagulation signals and broadband excitation voltage signals on the same bipolar surgical electrode. This allows for the dynamic reproduction of changes in the biological tissue state (such as temperature rise, dehydration, and denaturation) caused during electrocautery or electrocoagulation, while simultaneously measuring its frequency domain impedance characteristics. This overcomes the limitation of existing methods that cannot simulate the dynamic processes of tissue temperature rise and compression temperature rise caused by electrocautery or electrocoagulation, i.e., cannot reflect the impedance changes of tissue under real surgical conditions. 2) This invention adopts an independent circuit switch structure composed of bidirectional MOSFETs, which realizes electrical isolation and independent on / off control between the electrical switching / condensation circuit and the measurement circuit. This effectively prevents interference from high voltage and high current signals to weak measurement signals and equipment damage caused by current backflow, ensuring the safety and signal purity of the impedance measurement process. Attached Figure Description

[0010] Figure 1 This is a structural diagram of the dynamic testing system for the tissue frequency domain impedance characteristics of the present invention; Figure 2 This is a circuit diagram of the dual-channel control module in the dynamic testing system for tissue frequency domain impedance characteristics of the present invention. Figure 3 This is a circuit diagram of the control unit in the dynamic testing system for tissue frequency domain impedance characteristics of the present invention. Figure 4 This is a timing control diagram of the alternating output of the electro-cutting / electro-coagulation signal and the broadband excitation voltage signal according to the present invention; Figure 5 This is a schematic diagram of the timing control of the superimposed output of the electro-cutting / electro-coagulation signal and the broadband excitation voltage signal of the present invention; Figure 6 This is a flowchart illustrating the impedance frequency domain characteristics of the superimposed output of the electro-cutting / electro-coagulation signal and the broadband excitation voltage signal according to the present invention. Detailed Implementation

[0011] The present invention will be further described and illustrated below with reference to specific embodiments. The embodiments described are merely examples of the content of this disclosure and do not limit the scope of the invention. The technical features of each embodiment in the present invention can be combined accordingly, provided that there is no mutual conflict.

[0012] This invention proposes a dynamic testing method for the frequency domain impedance characteristics of tissues. This method can achieve alternating electrocautery and electrocoagulation operations with the testing of biological tissue impedance characteristics, and can also perform online testing of biological tissue impedance characteristics while performing electrocautery and electrocoagulation.

[0013] This invention proposes a dual-channel control circuit of "high-power cutting signal - wideband voltage excitation". This circuit can control the on and off of the dual signals and prevent current backflow from damaging the equipment.

[0014] This invention also proposes a dual-signal superposition output control method and an alternating output timing control method with dead time.

[0015] This invention also proposes a method for extracting frequency domain information from mixed signals, which can reconstruct the frequency domain impedance signal of biological tissues from high-voltage, large signals.

[0016] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0017] The structural diagram of the dynamic testing system for the tissue frequency domain impedance characteristics of this invention is shown below. Figure 1 As shown in the diagram, the system mainly includes an energy generator 1, a bipolar scalpel 2, a signal generator 4, an RF power amplifier module 5, a control unit 6, a dual-channel control module 7, a voltage probe 8, a current probe 9, an oscilloscope 10, a lock-in amplifier 11, a host computer 12, and a mounting bracket 13. The bipolar scalpel 2 has bipolar surgical electrodes used to contact the biological tissue 3 (the sample being tested) to be subjected to frequency domain impedance characteristic testing. The mounting bracket 13 is used to fix the bipolar scalpel 2.

[0018] The dual-channel control module 7 includes an electrocautery / electrocoagulation circuit switch and a measurement signal circuit switch. The energy generator 1 outputs an electrocautery / electrocoagulation signal, which is sequentially input into the biological tissue 3 to be tested for frequency domain impedance characteristics via the electrocautery / electrocoagulation circuit switch and a bipolar surgical electrode. This dynamically reproduces the changes in the biological tissue state caused by the electrocautery or electrocoagulation process on the biological tissue 3. The signal generator 4 outputs a wideband excitation voltage signal to the RF power amplifier module 5. The RF power amplifier module 5 amplifies the wideband excitation voltage signal, and the amplified wideband excitation voltage signal is sequentially input into the biological tissue 3 to be tested for frequency domain impedance characteristics via the measurement signal circuit switch and a bipolar surgical electrode.

[0019] Control unit 6 is used to control the output of electrocautery / coagulation signals from energy generator 1, and to control the on / off state of the two circuit switches. Voltage probe 8 is used to sample the voltage signal of the bipolar surgical electrode in real time when the signal generator 4 outputs a wideband excitation voltage signal to the biological tissue 3, and feeds it back to oscilloscope 10 or lock-in amplifier 11. Current probe 9 is used to sample the current signal of the bipolar surgical electrode in real time when the signal generator 4 outputs a wideband excitation voltage signal to the biological tissue 3, and feeds it back to oscilloscope 10 or lock-in amplifier 11.

[0020] When the energy generator 1 outputs an electro-switching / electrocoagulation signal, the signal generator 4 outputs a wideband excitation voltage signal, and both circuit switches are simultaneously turned on, the voltage probe 8 feeds back the sampled voltage signal to the lock-in amplifier 11, and the current probe 9 feeds back the sampled current signal to the lock-in amplifier 11. At the same time, the lock-in amplifier 11 also receives the wideband excitation voltage signal and obtains the voltage component amplitude, voltage component phase, current component amplitude, and current component phase at each preset discrete frequency point in the wideband excitation voltage from the voltage signal and the current signal, and outputs them to the host computer 12. Based on the voltage component amplitude, voltage component phase, current component amplitude, and current component phase at each preset discrete frequency point, the host computer 12 obtains the real-time impedance characteristic spectrum of the biological tissue 3 as a function of frequency, and completes the frequency domain impedance characteristic test of the biological tissue 3.

[0021] When the energy generator 1 outputs an electro-switching / electrocoagulation signal, the signal generator 4 outputs a wideband excitation voltage signal, and the two circuit switches are not simultaneously turned on, the voltage probe 8 feeds back the sampled voltage signal to the oscilloscope 10, and the current probe 9 feeds back the sampled current signal to the oscilloscope 10; the oscilloscope 10 then outputs the voltage and current signals to the host computer 12, and the host computer 12 obtains the real-time impedance characteristic spectrum of the biological tissue 3 as a function of frequency based on the voltage and current signals, thus completing the frequency domain impedance characteristic test of the biological tissue 3.

[0022] The principle of the dual-channel control module 7 is as follows: Figure 2 As shown, because MOSFET devices inherently possess parasitic body diodes, current may still flow in the reverse direction along the body diode even in the off state, preventing true bidirectional cutoff. Therefore, a bidirectional switching unit is constructed using two MOSFETs connected in series back-to-back with their sources opposite each other. This structure enables simultaneous conduction or blocking of current in both directions. The system comprises four bidirectional switching units. The bidirectional switch composed of MOSFETs Q1 and Q2, along with the bidirectional switch composed of MOSFETs Q3 and Q4, constitutes the electrocautery / coagulation circuit switch, used to control the electrocautery / coagulation circuit. One end of the electrocautery / coagulation circuit switch is connected to the energy generator 1, and the other end is connected to the bipolar surgical electrode (i.e.,...). Figure 2 The scalpel electrode in the circuit is connected to the MOSFET Q5. A bidirectional switch composed of MOSFETs Q5 and Q6, along with a bidirectional switch composed of MOSFETs Q7 and Q8, constitutes a measurement signal loop switch, used to control the measurement signal loop; one end of the measurement signal loop switch is connected to the RF power amplifier module 5 (i.e., MOSFET Q6). Figure 2 The circuit is connected to the radio frequency power amplifier, and the other end of the measurement signal circuit switch is connected to the bipolar surgical electrode. Through the combined control of the above-mentioned electrocautery / electrocoagulation circuit switch and the measurement signal circuit switch, the electrocautery / electrocoagulation circuit and the measurement signal circuit can be independently turned on and off.

[0023] The circuit schematic of control unit 6 is as follows: Figure 3 As shown, the control unit 6 includes a controller for outputting control commands. The controller is capable of outputting an electro-cutting / electrocoagulation output signal to the energy generator 1, and the controller is also capable of outputting an electro-cutting / electrocoagulation circuit switch signal to the electro-cutting / electrocoagulation circuit switch (i.e.,...). Figure 3 The electrical cut / coagulation circuit switch in the middle), and the switch that can output the measurement signal loop switch signal to the measurement signal loop switch (i.e. Figure 3 The control unit 6 (including the measurement signal path switches) is used to achieve independent control of each functional module of the system. Specifically, the electrocautery / electrocoagulation circuit switch signal controls the on / off state of the electrocautery / electrocoagulation circuit switch; the measurement signal circuit switch signal controls the on / off state of the measurement signal circuit switch; and the electrocautery / electrocoagulation output signal drives the energy generator 1 to output electrocautery / electrocoagulation signals, enabling the energy generator 1 to output effective therapeutic energy in electrocautery or electrocoagulation mode. Through these three control signals, the control unit 6 can coordinate and control the treatment circuit, measurement circuit, and the trigger output of therapeutic energy, thereby achieving orderly switching between the therapeutic function and the impedance measurement function.

[0024] The control timing diagrams for the electro-cutting / electrocoagulation signals and the broadband excitation voltage signals are as follows: Figure 4 and Figure 5 As shown, in the superimposed output mode, i.e., when the electrocautery / coagulation signal and the broadband excitation voltage signal are simultaneously input to the bipolar surgical electrode, the electrocautery / coagulation circuit switch and the measurement signal circuit switch are synchronously turned on, such as... Figure 5 As shown. In the alternating output mode, that is, when the electrocautery / coagulation signal and the wideband excitation voltage signal are not simultaneously input to the bipolar surgical electrode, the electrocautery / coagulation circuit switch and the measurement signal circuit switch are alternately turned on. When the electrocautery / coagulation circuit switch is turned on, the energy generator 1 synchronously outputs the electrocautery / coagulation signal.

[0025] In a specific embodiment of the present invention, the workflow of the dynamic testing method for tissue frequency domain impedance characteristics of the present invention is as follows: When control unit 6 controls energy generator 1 to output electrocautery / coagulation signals and controls both circuit switches to be turned on simultaneously, energy generator 1 outputs electrocautery / coagulation signals. These signals are sequentially input into the biological tissue 3 to be tested for frequency domain impedance characteristics via the electrocautery / coagulation circuit switches and bipolar surgical electrodes, dynamically reproducing the changes in the biological tissue state caused by the electrocautery or coagulation process. Simultaneously, signal generator 4 outputs a wideband excitation voltage signal to RF power amplifier module 5. RF power amplifier module 5 amplifies the wideband excitation voltage signal, and the amplified wideband excitation voltage signal is sequentially input into the biological tissue 3 via the measurement signal circuit switch and bipolar surgical electrodes. Voltage probe 8 samples the signals in real time. The voltage signal of the bipolar surgical electrode is fed back to the lock-in amplifier 11; the current probe 9 samples the current signal of the bipolar surgical electrode in real time and feeds it back to the lock-in amplifier 11; at the same time, the lock-in amplifier 11 also receives the broadband excitation voltage signal, and obtains the voltage component amplitude, voltage component phase, current component amplitude, and current component phase at each preset discrete frequency point in the broadband excitation voltage from the voltage signal and the current signal, and outputs them to the host computer 12. The host computer 12 obtains the real-time impedance characteristic spectrum of the biological tissue 3 as a function of frequency based on the voltage component amplitude, voltage component phase, current component amplitude, and current component phase at each preset discrete frequency point, and completes the frequency domain impedance characteristic test of the biological tissue 3.

[0026] When the control unit controls the electrocautery / coagulation circuit switch to be turned on and then off, and controls the measurement signal circuit switch to be turned off first, and controls the energy generator 1 to output electrocautery / coagulation signals when the electrocautery / coagulation circuit switch is turned on, the energy generator 1 first outputs the electrocautery / coagulation signals. The electrocautery / coagulation signals are sequentially input into the biological tissue 3 to be tested for frequency domain impedance characteristics through the electrocautery / coagulation circuit switch and the bipolar surgical electrode, dynamically reproducing the changes in the state of the biological tissue caused by the electrocautery or coagulation process on the biological tissue 3. Then, the signal generator 4 outputs a wideband excitation voltage signal to the radio frequency power amplifier module 5. 5. The wideband excitation voltage signal is amplified by power. The amplified wideband excitation voltage signal is then input into the biological tissue 3 through the measurement signal loop switch and the bipolar surgical electrode. At the same time, the voltage probe 8 samples the voltage signal of the bipolar surgical electrode in real time and feeds it back to the oscilloscope 10. The current probe 9 samples the current signal of the bipolar surgical electrode in real time and feeds it back to the oscilloscope 10. The oscilloscope 10 then outputs the voltage signal and current signal to the host computer 12. The host computer 12 obtains the real-time impedance characteristic spectrum of the biological tissue 3 as a function of frequency based on the voltage signal and current signal, thus completing the frequency domain impedance characteristic test of the biological tissue 3.

[0027] Energy generator 1 sends a high-power electrocautery / coagulation signal to the sample under test via bipolar surgical electrodes to simulate surgical procedures. A wideband excitation voltage signal from signal generator 4 is amplified by radio frequency power amplifier module 5 and then fed into the sample under test via bipolar surgical electrodes. Control unit 6 drives the switching of dual-channel control module 7, thereby controlling the connection between energy generator 1 and radio frequency power amplifier module 5.

[0028] When the electrocautery / coagulation circuit switch and the measurement signal circuit switch are set to alternate conduction, the output of high-power electrocautery / coagulation signals and wideband excitation voltage signals can be executed sequentially to achieve long-term monitoring of tissue impedance characteristics after the electrocautery / coagulation operation is completed. At this time, the wideband voltage excitation and wideband current response output by the bipolar surgical electrode are acquired by oscilloscope 10, and the frequency domain impedance characteristics of the sample under test can be obtained by offline processing.

[0029] If both the electrocautery / coagulation circuit switch and the measurement signal circuit switch are set to ON, the high-power electrocautery / coagulation signal can be superimposed with the wideband excitation voltage signal and input to the sample under test. In this case, if the voltage probe 8, current probe 9, and oscilloscope 10 are used directly to test the relatively weak voltage and current across the bipolar surgical electrodes, the test results will be affected by the electrocautery / coagulation signal (high voltage, high current). Therefore, a lock-in amplifier 11 is needed to separately pick up the voltage and current signals acquired by the probes based on the discrete frequency points in the wideband excitation voltage signal. The impedance frequency domain characteristic processing flow for dual-channel signal superposition output is as follows: Figure 6 As shown.

[0030] The wideband excitation voltage signal emitted by signal generator 4 is composed of multiple discrete frequencies. f 1. f 2、…、 f n The superimposed structure, after being amplified by the RF power amplifier module 5, still results in a wideband excitation voltage signal with a frequency of [missing information]. f 1. f 2、…、 f n When the wideband excitation voltage signal and the high-power electrocautery / coagulation signal are superimposed and flow through biological tissue 3 by setting the on / off state of the dual-channel control circuit, the wideband information of biological tissue 3 is overwhelmed by the high-power high-voltage signal, making it difficult to test. A lock-in amplifier 11 is used to connect the bipolar surgical electrodes with a frequency of... f 1. f 2、…、 f n The signal was extracted and reconstructed to obtain biological tissue 3 at a frequency of f 1. f 2、…、 f n The voltage component at that time is U 1.U 2、…、 U n At a frequency of f 1. f 2、…、 f n The current component at time is I 1. I 2、…、 I n Using Ohm's law, we can obtain the biological tissue 3 in... f 1. f 2、…、 f n The impedance magnitude at that time is Z 1. Z 2、…、 Z n This refers to the frequency domain impedance characteristics of the tissue.

[0031] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. Those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A dynamic testing system for the frequency domain impedance characteristics of an organization, characterized in that, It includes an energy generator, a bipolar scalpel, a signal generator, an RF power amplifier module, a control unit, a dual-channel control module, a sampling probe, and a testing unit; the bipolar scalpel has bipolar surgical electrodes, which are used to contact the biological tissue to be tested for frequency domain impedance characteristics; The dual-channel control module includes a first-loop switch and a second-loop switch; an energy generator is used to output electrocautery / electrocoagulation signals, which are sequentially input into the biological tissue through the first-loop switch and a bipolar surgical electrode, dynamically reproducing the changes in the biological tissue state caused by the electrocautery or electrocoagulation process; a signal generator is used to output a wideband excitation voltage signal to the radio frequency power amplifier module, which amplifies the wideband excitation voltage signal, and the amplified wideband excitation voltage signal is sequentially input into the biological tissue through the second-loop switch and a bipolar surgical electrode. The control unit is used to control the on / off state of the two circuit switches; the sampling probe is used to sample the voltage and current signals of the bipolar surgical electrode in real time when the signal generator outputs a wideband excitation voltage signal to the biological tissue, and feed it back to the test unit. Based on the received voltage and current signals, the test unit obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency, thus completing the frequency domain impedance characteristic test of the biological tissue.

2. The dynamic testing system for tissue frequency domain impedance characteristics according to claim 1, characterized in that, The testing unit includes an oscilloscope, a lock-in amplifier, and a host computer; When both circuit switches are turned on simultaneously, the sampling probe feeds back the voltage and current signals to the lock-in amplifier. At the same time, the lock-in amplifier also receives the broadband excitation voltage signal and obtains the voltage component amplitude, voltage component phase, current component amplitude, and current component phase at each preset discrete frequency point in the broadband excitation voltage from the voltage and current signals. The results are then output to the host computer. Based on the voltage component amplitude, voltage component phase, current component amplitude, and current component phase at each preset discrete frequency point, the host computer obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency. When the two circuit switches are not turned on at the same time, the sampling probe feeds back the voltage and current signals to the oscilloscope, which then outputs the voltage and current signals to the host computer. The host computer obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency based on the voltage and current signals.

3. The dynamic testing system for tissue frequency domain impedance characteristics according to claim 1, characterized in that, Both the first circuit switch and the second circuit switch include bidirectional switching transistors, which adopt a bidirectional switching structure consisting of two power MOSFETs connected back-to-back in a common source configuration.

4. The dynamic testing system for tissue frequency domain impedance characteristics according to claim 1, characterized in that, The sampling probe includes a voltage sampling probe and a current sampling probe; the voltage sampling probe is used to sample the voltage signal of the bipolar surgical electrode in real time when the signal generator outputs a wideband excitation voltage signal to the biological tissue; the current sampling probe is used to sample the current signal of the bipolar surgical electrode in real time when the signal generator outputs a wideband excitation voltage signal to the biological tissue.

5. The dynamic testing system for tissue frequency domain impedance characteristics according to claim 1, characterized in that, The testing system includes a fixation bracket; the fixation bracket is used to fix the bipolar scalpel.

6. The dynamic testing system for tissue frequency domain impedance characteristics according to claim 1, characterized in that, The control unit is also used to control the energy generator to output electrical cutting / coagulation signals.

7. A dynamic testing method for the frequency domain impedance characteristics of an organization using the testing system described in any one of claims 1-6, characterized in that, Includes the following steps: When the control unit simultaneously activates both loop switches, the energy generator outputs an electrocautery / coagulation signal. This signal passes sequentially through the first loop switch and the bipolar surgical electrode into the biological tissue, dynamically reproducing the tissue state changes induced by the electrocautery or coagulation process. Simultaneously, the signal generator outputs a wideband excitation voltage signal to the radio frequency power amplifier module. The module amplifies the signal, and the amplified signal passes sequentially through the second loop switch and the bipolar surgical electrode into the biological tissue. The sampling probe samples the voltage and current signals from the bipolar surgical electrode in real time and feeds them back to the testing unit. Based on the received voltage and current signals, the test unit obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency, thus completing the frequency domain impedance characteristic test of the biological tissue. When the control unit controls the two circuit switches to not be turned on at the same time, and the first circuit switch is turned on first and then turned off, and the second circuit switch is turned off first and then turned off; the energy generator first outputs an electrocautery / electrocoagulation signal to the biological tissue; then the signal generator outputs a wideband excitation voltage signal to the biological tissue, and at the same time the sampling probe samples the voltage and current signals of the bipolar surgical electrode in real time and feeds them back to the test unit; Based on the received voltage and current signals, the test unit obtains the real-time impedance characteristic spectrum of the biological tissue as a function of frequency.

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