A performance evaluation processing system and method for EIT imaging equipment

Abstract

The present invention discloses a system and method for evaluating the performance of EIT imaging equipment. The system includes: a loop circuit formed by N loop resistors connected in series in sequence and N detection branches, and any one detection branch is set at a connection node between two adjacent loop resistors on the loop circuit; the N loop resistors are any one of 16, 32, and 64; wherein each of the detection branches includes an adjustable resistor component and an electrode buckle; the electrode buckle on the detection branch is used to connect the electrode of the EIT imaging equipment. The detection branch is used to obtain the voltage signal of the EIT equipment under different impedance conditions; the collected voltage signal is subjected to stability statistical processing to achieve evaluation processing of the performance of the EIT imaging equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of EIT imaging equipment, and in particular to a system and method for evaluating the performance of EIT imaging equipment. Background Art

[0002] As we all know, bioelectrical impedance tomography (EIT imaging equipment) achieves non-invasive imaging of the electrical impedance distribution inside tissues by applying a small current on the tissue surface and measuring the response voltage, combined with advanced image reconstruction algorithms. Its fast, real-time, low-cost and high-safety characteristics give it unique advantages in medical monitoring and diagnosis, especially for clinical scenarios that require frequent monitoring and dynamic observation. However, the spatial resolution of EIT is relatively low and it is highly dependent on image reconstruction algorithms, so continuous technological innovation and algorithm optimization remain the key to enhancing its application value.

[0003] At present, the performance evaluation scheme for EIT equipment generally uses a container that can hold water or other conductive liquids. The electrical impedance distribution in the container is changed by putting or removing objects in the liquid, and then the liquid in the container is connected to the EIT cable outside the container through a special metal buckle on the container wall, so that the EIT device can directly measure the impedance in the container and calculate the impedance distribution image. By comparing the impedance distribution image with the objects put in or taken out, the performance of the equipment can be judged.

[0004] However, further research has found that the existing technical performance evaluation scheme still has the following shortcomings: the performance of EIT imaging devices varies, and there is no targeted scientific evaluation method for their specific functionality and reliability; for example, the current performance evaluation scheme for EIT imaging devices generally uses a container that can hold water or other conductive liquids, and changes the electrical impedance distribution in the container by placing or removing objects in the liquid, and then connects the liquid in the container to the EIT cable outside the container through a special metal buckle on the container wall, so that the EIT imaging device can directly measure the impedance in the container and calculate the impedance distribution image. By comparing the impedance distribution image with the objects placed in or taken out, the performance of the EIT imaging device can be judged. However, this processing method, which uses a container water storage model to evaluate the performance of EIT imaging equipment, often fails to achieve quantitative, accurate, and reliable performance evaluation. Summary of the invention

[0005] In view of the above problems, the present invention provides a device and method for EIT performance evaluation. Based on the hardware measurement principle of EIT, the device constructs a flexible, configurable, and high-precision impedance test model, which can achieve accurate and comprehensive performance evaluation of EIT imaging equipment and provide technical decision support for ensuring the reliability and stability of subsequent use of EIT imaging equipment.

[0006] The present invention provides a performance evaluation processing system for an EIT imaging device, comprising:

[0007] The invention comprises: a loop circuit formed by N loop resistors 1 connected in series in sequence and N detection branches 2, wherein any one of the detection branches 2 is arranged at a connection node between two adjacent loop resistors 1 on the loop circuit; the N loop resistors are any one of 16, 32, and 64;

[0008] Each of the detection branches 2 includes an adjustable resistor component 20 and an electrode buckle 21; the electrode buckle 21 on the detection branch 2 is used to connect the electrode of the EIT imaging device;

[0009] The loop circuit is used to simulate the impedance distribution of the EIT device; the detection branch 2 is used to obtain the voltage signal of the EIT device under different impedance conditions; and the collected voltage signal is subjected to stability statistical processing.

[0010] Preferably, as an implementable method, each of the detection branches 2 is used to sequentially connect the 1-N electrodes of the EIT imaging device to the electrode buckles in sequence during the detection of the EIT imaging device, and to sample the excitation current generated by the electrode connected to the currently selected target measurement on the current detection branch, while the other detection branches are used to sample the voltages of the remaining electrodes;

[0011] The other detection branches 2 are used to measure voltage. The measured voltage theoretical value is the current i on the 15 detection branches multiplied by the resistance value R between the adjacent electrodes, that is, u=i*R; wherein R is a known value;

[0012] The detection branch 2 is used to sample and calculate the excitation current generated by the electrode currently selected for target measurement: if the excitation current is I, the resistance values ​​of the 16 loop resistors are R1, R2, R3, ..., R16, and the resistance value between the excitation electrodes is R1, then i is calculated by the following formula i=R1 / (R1+R2+R3+R4+...+R15+R16);

[0013] According to this rule, the ideal value of all voltage values ​​measured by the EIT imaging device is calculated According to the ideal value of voltage The voltage measurement error is obtained by comparing the voltage measured value U with the output of the operation:

[0014] Preferably, as an implementable method, the three parallel branches of the adjustable resistance component 20 are connected in parallel from top to bottom, and each parallel branch arranged from top to bottom is respectively connected with a plurality of fixed capacitors 201, a plurality of fixed resistors 202, and a potentiometer 203 (variable resistor):

[0015] A control switch 204 is provided on the circuit where each parallel branch is located. The control switch can be used to connect or disconnect the fixed resistor 202 and the fixed capacitor 201.

[0016] A control switch 204 is provided on the circuit where each parallel branch is located. The control switch can be used to connect or disconnect the fixed resistor 202 and the fixed capacitor 201.

[0017] Preferably, as an implementable method, it also includes a contact impedance simulation module; the contact impedance simulation module is also composed of an adjustable resistance component.

[0018] It should be noted that, since the EIT imaging device is inevitably troubled by the problem of contact between the electrode and the skin surface during use, the contact impedance simulation is reserved in the performance evaluation device. The contact impedance simulation is also composed of the above-mentioned adjustable resistance component (see the general diagram) to fully simulate the actual use scenario.

[0019] Preferably, as an implementable method; when the loop circuit is used, the resistance values ​​of the loop resistors in the loop circuit are first set to be equal, and the potentiometer 203 on the detection branch and the control switch 204 on the fixed capacitor 201 are closed, so that the resistance in the loop is only provided by the fixed resistor 202; and after the contact resistance values ​​are adjusted to 0, the detection circuit records the voltage measurement value V at this time, and then selects one of the electrodes to adjust the contact impedance of the electrode; gradually increases the contact impedance, observes the voltage values ​​measured by the electrode and the remaining electrodes, and when the voltage value change reaches 5%, records the adjusted contact impedance Rc at this time; and determines that the higher the input impedance of the EIT imaging device, the larger the measured Rc, and the more accurate the measurement value obtained by the EIT imaging device.

[0020] Preferably, as an implementable method, it also includes a voltage and current acquisition stability statistics module; the voltage and current acquisition stability statistics module is used to continuously monitor the voltage value or current value of the measurement signal of each current channel signal acquired by the device, and count the maximum and minimum values ​​within any preset time window, and calculate the difference between the maximum and minimum values ​​and record it as the jitter amplitude; calculate the percentage of the jitter amplitude of the current channel = (maximum value-minimum value) / minimum value, and evaluate the stability of voltage acquisition or current acquisition according to the percentage of the jitter amplitude of the current channel.

[0021] Preferably, as an implementable method, the voltage and current acquisition stability statistics module is used to evaluate and process according to the percentage of the jitter amplitude of the current channel. If the percentage of the jitter amplitude of the current channel is smaller, it is determined that the stability of the voltage acquisition or current acquisition is better.

[0022] A method for evaluating the performance of an EIT device comprises the following steps:

[0023] connecting the EIT device to the performance evaluation processing system for the EIT imaging device;

[0024] Adjust the resistance value of the adjustable resistor component to simulate different impedance distributions;

[0025] Record the voltage measurements of the EIT equipment under different impedance conditions;

[0026] Compare the recorded voltage measurements with the theoretical values ​​and calculate the measurement error;

[0027] The performance of EIT equipment is evaluated by statistically analyzing the stability of voltage and current acquisition.

[0028] Preferably, as an implementable method; when the loop circuit is used, first, the resistance values ​​of the loop resistors in the loop circuit are set to be equal, and the potentiometer 203 on the detection branch and the control switch 204 on the fixed capacitor 201 are closed, so that the resistance in the loop is only provided by the fixed resistor 202; and after the contact resistance values ​​are adjusted to 0, the detection circuit records the voltage measurement value V at this time, and then selects one of the electrodes to adjust the contact impedance of the electrode; gradually increase the contact impedance, observe the voltage values ​​measured by the electrode and the remaining electrodes, and when the voltage value change reaches 5%, record the adjusted contact impedance Rc at this time; and determine that the higher the input impedance of the EIT imaging device, the larger the measured Rc, and the more accurate the measurement value obtained by the EIT imaging device.

[0029] Preferably, as an implementable method, the voltage and current acquisition stability statistics module continuously monitors the voltage value or current value of the measured signal of each current channel signal acquired by the device, and counts the maximum value and the minimum value within any preset time window, and calculates the difference between the maximum value and the minimum value and records it as the jitter amplitude; calculates the percentage of the jitter amplitude of the current channel = (maximum value - minimum value) / minimum value, and evaluates the stability of the voltage acquisition or current acquisition according to the percentage of the jitter amplitude of the current channel;

[0030] The evaluation process is performed based on the percentage of the jitter amplitude of the current channel. If the percentage of the jitter amplitude of the current channel is smaller, it is determined that the stability of the voltage acquisition or current acquisition is better.

[0031] Compared with the prior art, the present invention has at least the following technical effects:

[0032] The present invention designs a performance evaluation device based on the use principle of the EIT imaging device, and produces a set of effective performance evaluation methods, which realizes accurate performance evaluation of the EIT imaging device through quantitative means. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram of the adjacent electrode method of the EIT imaging device;

[0034] Figure 2 A schematic diagram of the main circuit of a performance evaluation processing system for EIT imaging equipment;

[0035] Figure 3 The present invention is a circuit diagram of an adjustable resistance component used in a performance evaluation processing system of an EIT imaging device.

[0036] Reference numerals: loop resistor 1; detection branch 2; adjustable resistor component 20; fixed capacitor 201; fixed resistor 202; potentiometer 203; control switch 204; electrode buckle 21. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] The present invention is further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0039] First, the device to be evaluated, namely the EIT imaging device, is introduced: the evaluation processing system (also known as the impedance model) in the technical solution of the present invention is mainly used in the EIT imaging device. When the patient uses it, he needs to tie an electrode belt. There are 16 electrodes on the electrode belt. When the device is working normally, the adjacent injection method is usually used for impedance measurement. Taking the 16-electrode cylindrical conductor as an example, Figure 1 Schematic diagram of the adjacent electrode method.

[0040] First, select electrode 1 and electrode 2 as excitation, measure the voltage between electrode 3 and electrode 4, electrode 4 and electrode 5, ..., until electrode 15 and electrode 16, and obtain 13 measurement values. Then, select electrode 2 and electrode 3 as excitation, measure the voltage between electrode 4 and electrode 5, electrode 5 and electrode 6, ..., until electrode 16 and electrode 1, and obtain 13 measurement values. In this way, select electrode 3 and electrode 4, electrode 4 and electrode 5, electrode 5 and electrode 6, until electrode 16 and electrode 1 as excitation, measure the voltage of other adjacent electrode pairs, and obtain 13x 16 = 208 measurement values ​​in total.

[0041] like Figure 2 As shown, an embodiment of the present invention provides a performance evaluation processing system for EIT imaging equipment; the architecture block diagram of the performance evaluation processing system for EIT imaging equipment is applicable to EIT imaging equipment with different configurations such as 16 electrodes, 32 electrodes, and 64 electrodes. Each electrode is connected to the device cable through an electrode buckle, and the box position represents an adjustable resistor component. The device simulates different impedance distributions by configuring the resistance value to achieve performance evaluation of the EIT device. Each electrode is connected to the device cable through an electrode buckle, and the box position represents an adjustable resistor component. The evaluation processing system of the present invention simulates different impedance distributions by configuring the resistance value to achieve performance evaluation of the EIT device. Among them, Figure 2 The dots in the figure represent the electrode buckles connected to the device cable, and each box position represents an adjustable resistor component.

[0042] like Figure 2 As shown, the present invention provides a performance evaluation processing system for EIT imaging equipment, comprising: N loop resistors 1 are sequentially connected in series to form a loop circuit and N detection branches 2, and any one of the detection branches 2 is arranged at a connection node between two adjacent loop resistors 1 on the loop circuit; the N loop resistors are any one of 16, 32, and 64;

[0043] Each of the detection branches 2 includes an adjustable resistor component 20 and an electrode buckle 21; the electrode buckle 21 on the detection branch 2 is used to connect the electrode of the EIT imaging device;

[0044] The loop circuit is used to simulate the impedance distribution of the EIT device; the detection branch 2 is used to obtain the voltage signal of the EIT device under different impedance conditions; and the collected voltage signal is subjected to stability statistical processing.

[0045] Preferably, as an implementable method, each of the detection branches 2 is used to sequentially connect the 1-N electrodes of the EIT imaging device to the electrode buckles in sequence during the detection of the EIT imaging device, and to sample the excitation current generated by the electrode connected to the currently selected target measurement on the current detection branch, while the other detection branches are used to sample the voltages of the remaining electrodes;

[0046] The other detection branches 2 are used to measure voltage. The measured voltage theoretical value is the current i on the 15 detection branches multiplied by the resistance value R between the adjacent electrodes, that is, u=i*R; wherein R is a known value;

[0047] The detection branch 2 is used to sample and calculate the excitation current generated by the electrode currently selected for target measurement: if the excitation current is I, the resistance values ​​of the 16 loop resistors are R1, R2, R3, ..., R16, and the resistance value between the excitation electrodes is R1, then i is calculated by the following formula i=R1 / (R1+R2+R3+R4+...+R15+R16);

[0048] According to this rule, the ideal value of all voltage values ​​measured by the EIT imaging device is calculated According to the ideal value of voltage The voltage measurement error is obtained by comparing the voltage measured value U with the output of the operation:

[0049] In the specific technical solution of the present invention, regarding the adjustable resistance component 20;

[0050] like Figure 3 As shown, the adjustable resistance component 20 has three parallel branches from top to bottom, and each parallel branch arranged from top to bottom is respectively connected with a plurality of fixed capacitors 201, a plurality of fixed resistors 202, and a potentiometer 203 (variable resistor): that is, the structure of the adjustable resistance component 20 is shown in the figure, which is composed of a plurality of fixed capacitors 201, a plurality of fixed resistors 202, and a potentiometer 203 connected in parallel;

[0051] A control switch 204 is provided on the circuit where each parallel branch is located. The control switch can be used to connect or disconnect the fixed resistor 202 and the fixed capacitor 201.

[0052] Among them, a potentiometer 203 is used to fine-tune the resistance of the current parallel branch, and can almost achieve continuous adjustment of the resistance; a number of fixed resistors 202 are used for high-precision resistance adjustment, but cannot achieve continuous adjustment of the resistance. The resistance can only be adjusted by switching in a fixed switching mode, but the resistance switching can be fully controlled. The above-mentioned several fixed capacitors 201 are used to adjust the capacitive load of the adjustable resistance component, so that it can fully verify and measure the equipment.

[0053] Each parallel branch is provided with a control switch 204, which can be used to connect or disconnect the fixed resistor 202 and the fixed capacitor 201, making the adjustment of the device intuitive and simple. The adjustable resistor component is used to achieve full adjustability of the measurement environment to achieve its intended purpose.

[0054] Preferably, as an implementable embodiment, it also includes a contact impedance simulation module (not shown in the figure); the contact impedance simulation module is also composed of an adjustable resistance component.

[0055] It should be noted that, since the EIT imaging device is inevitably troubled by the problem of contact between the electrode and the skin surface during use, the contact impedance simulation is reserved in the performance evaluation device. The contact impedance simulation is also composed of the above-mentioned adjustable resistance component to fully simulate the actual use scenario.

[0056] Preferably, as an implementable method; when the loop circuit is used, the resistance values ​​of the loop resistors in the loop circuit are first set to be equal, and the potentiometer 203 on the detection branch and the control switch 204 on the fixed capacitor 201 are closed, so that the resistance in the loop is only provided by the fixed resistor 202; and after the contact resistance values ​​are adjusted to 0, the detection circuit records the voltage measurement value V at this time, and then selects one of the electrodes to adjust the contact impedance of the electrode; gradually increases the contact impedance, observes the voltage values ​​measured by the electrode and the remaining electrodes, and when the voltage value change reaches 5%, records the adjusted contact impedance Rc at this time; and determines that the higher the input impedance of the EIT imaging device, the larger the measured Rc, and the more accurate the measurement value obtained by the EIT imaging device.

[0057] Preferably, as an implementable method, it also includes a voltage and current acquisition stability statistics module; the voltage and current acquisition stability statistics module is used to continuously monitor the voltage value or current value of the measurement signal of each current channel signal acquired by the device, and count the maximum and minimum values ​​within any preset time window, and calculate the difference between the maximum and minimum values ​​and record it as the jitter amplitude; calculate the percentage of the jitter amplitude of the current channel = (maximum value-minimum value) / minimum value, and evaluate the stability of voltage acquisition or current acquisition according to the percentage of the jitter amplitude of the current channel.

[0058] Preferably, as an implementable method, the voltage and current acquisition stability statistics module is used to evaluate and process according to the percentage of the jitter amplitude of the current channel. If the percentage of the jitter amplitude of the current channel is smaller, it is determined that the stability of the voltage acquisition or current acquisition is better.

[0059] Embodiment 2

[0060] Embodiment 2 of the present invention provides a method for evaluating the performance of an EIT device, comprising the following steps:

[0061] connecting the EIT device to the performance evaluation processing system for the EIT imaging device;

[0062] Adjust the resistance value of the adjustable resistor component to simulate different impedance distributions;

[0063] Record the voltage measurements of the EIT equipment under different impedance conditions;

[0064] Compare the recorded voltage measurements with the theoretical values ​​and calculate the measurement error;

[0065] The performance of EIT equipment is evaluated by statistically analyzing the stability of voltage and current acquisition.

[0066] Preferably, as an implementable method; when the above-mentioned loop circuit is used, the resistance values ​​of the loop resistors in the loop circuit are first set to be equal, and the potentiometer 203 on the detection branch and the control switch 204 on the fixed capacitor 201 are turned off, so that the resistance in the loop is only provided by the fixed resistor 202; and after the contact resistance values ​​are adjusted to 0, the detection circuit records the voltage measurement value V at this time, and then selects one of the electrodes to adjust the contact impedance of the electrode; gradually increases the contact impedance, observes the voltage values ​​measured by the electrode and the remaining electrodes, and when the voltage value change reaches 5%, records the adjusted contact impedance Rc at this time; and determines that the higher the input impedance of the EIT imaging device, the larger the measured Rc, and the more accurate the measurement value obtained by the EIT imaging device.

[0067] Preferably, as an implementable method, the voltage and current acquisition stability statistics module continuously monitors the voltage value or current value of the measured signal of each current channel signal acquired by the device, and counts the maximum value and the minimum value within any preset time window, and calculates the difference between the maximum value and the minimum value and records it as the jitter amplitude; calculates the percentage of the jitter amplitude of the current channel = (maximum value - minimum value) / minimum value, and evaluates the stability of the voltage acquisition or current acquisition according to the percentage of the jitter amplitude of the current channel;

[0068] The evaluation process is performed based on the percentage of the jitter amplitude of the current channel. If the percentage of the jitter amplitude of the current channel is smaller, it is determined that the stability of the voltage acquisition or current acquisition is better.

[0069] In summary, the embodiment of the present invention designs a performance evaluation device based on the use principle of the EIT imaging device, and produces a set of effective performance evaluation methods, which realizes accurate performance evaluation of the EIT imaging device through quantitative means.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. A person skilled in the art may modify the technical solutions described in the above embodiments, or replace part or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A performance evaluation processing system for EIT imaging equipment, characterized in that: include: The invention is composed of N loop resistors (1) connected in series in sequence to form a loop circuit and N detection branches (2), and any one of the detection branches (2) is arranged at a connection node between two adjacent loop resistors (1) on the loop circuit; the N loop resistors are any one of 16, 32, and 64; Each of the detection branches (2) comprises an adjustable resistor component (20) and an electrode buckle (21); the electrode buckle (21) on the detection branch (2) is used to connect the electrode of the EIT imaging device; The loop circuit is used to simulate the impedance distribution of the EIT device; the detection branch (2) is used to obtain the voltage signal of the EIT device under different impedance conditions; and the collected voltage signal is subjected to stability statistical processing.

2. The performance evaluation processing system for EIT imaging equipment according to claim 1, characterized in that: Each of the detection branches (2) is used to sequentially connect 1-N electrodes of the EIT imaging device to the electrode buckles in sequence during the detection of the EIT imaging device, and to sample the excitation current generated by the electrode connected to the currently selected target measurement on the current detection branch, while the other detection branches are used to sample the voltages of the remaining electrodes; The other detection branches (2) are used to measure voltage, and the measured voltage theoretical value is the current i on the 15 detection branches multiplied by the resistance value R between the adjacent electrodes, that is, u=i*R; wherein R is a known value; The detection branch (2) is used for sampling and calculating the excitation current generated by the electrode currently selected for target measurement: if the excitation current is I, the resistance values ​​of the 16 loop resistors are R1, R2, R3, ..., R16 respectively, and the resistance value between the excitation electrodes is R1, then i is calculated by the following calculation formula: i=R1 / (R1+R2+R3+R4+...+R15+R16); According to this rule, the ideal value of all voltage values ​​measured by the EIT imaging device is calculated According to the ideal value of voltage The voltage measurement error is obtained by comparing the voltage measured value U with the voltage measured value U: e = (the ideal value of the voltage value – Actual voltage value U) / ideal voltage value 3. The performance evaluation processing system for EIT imaging equipment according to claim 2, characterized in that: The adjustable resistance component (20) has three parallel branches arranged from top to bottom in parallel, and each parallel branch arranged from top to bottom is respectively connected with a plurality of fixed capacitors (201), a plurality of fixed resistors (202), and a potentiometer (203): A control switch (204) is provided on the circuit where each parallel branch is located, and the control switch can be used to connect or disconnect the fixed resistor (202) and the fixed capacitor (201).

4. The performance evaluation processing system for EIT imaging equipment according to claim 3, characterized in that: It also includes a contact impedance simulation module; the contact impedance simulation module is also composed of an adjustable resistance component.

5. The performance evaluation processing system for EIT imaging equipment according to claim 1, characterized in that: When the loop circuit is used, the resistance values ​​of the loop resistors in the loop circuit are first set to be equal, and the potentiometer (203) on the detection branch and the control switch (204) on the fixed capacitor (201) are closed, so that the resistance value in the loop is only provided by the fixed resistor (202); and after the contact resistance values ​​are all adjusted to 0, the detection circuit records the voltage measurement value V at this time, and then selects one of the electrodes to adjust the contact impedance of the electrode; gradually increases the contact impedance, observes the voltage values ​​measured by the electrode and the remaining electrodes, and when the voltage value change reaches 5%, records the adjusted contact impedance Rc at this time; and determines that the higher the input impedance of the EIT imaging device, the larger the measured Rc, and the more accurate the measurement value obtained by the EIT imaging device.

6. The performance evaluation processing system for EIT imaging equipment according to claim 1, characterized in that: It also includes a voltage and current acquisition stability statistics module; the voltage and current acquisition stability statistics module is used to continuously monitor the voltage value or current value of the measurement signal of each current channel signal collected by the device, and to count the maximum and minimum values ​​within any preset time window, and calculate the difference between the maximum and minimum values ​​and record it as the jitter amplitude; calculate the percentage of the jitter amplitude of the current channel = (maximum value-minimum value) / minimum value, and evaluate the stability of voltage acquisition or current acquisition according to the percentage of the jitter amplitude of the current channel.

7. The performance evaluation processing system for EIT imaging equipment according to claim 5, characterized in that: The voltage and current acquisition stability statistics module is used for evaluating and processing according to the percentage of the jitter amplitude of the current channel. If the percentage of the jitter amplitude of the current channel is smaller, it is determined that the stability of voltage acquisition or current acquisition is better.

8. A method for evaluating the performance of an EIT device, characterized in that: The following steps are involved: connecting the EIT device to the performance evaluation processing system for the EIT imaging device; Adjust the resistance value of the adjustable resistor component to simulate different impedance distributions; Record the voltage measurements of the EIT equipment under different impedance conditions; Compare the recorded voltage measurements with the theoretical values ​​and calculate the measurement error; The performance of EIT equipment is evaluated by statistically analyzing the stability of voltage and current acquisition.

9. The method according to claim 8, characterized in that When the loop circuit is used, the resistance values ​​of the loop resistors in the loop circuit are first set to be equal, and the potentiometer (203) on the detection branch and the control switch (204) on the fixed capacitor (201) are closed, so that the resistance value in the loop is only provided by the fixed resistor (202); and after the contact resistance values ​​are all adjusted to 0, the detection circuit records the voltage measurement value V at this time, and then selects one of the electrodes to adjust the contact impedance of the electrode; gradually increases the contact impedance, observes the voltage values ​​measured by the electrode and the remaining electrodes, and when the voltage value change reaches 5%, records the adjusted contact impedance Rc at this time; and determines that the higher the input impedance of the EIT imaging device, the larger the measured Rc, and the more accurate the measurement value obtained by the EIT imaging device.

10. The method according to claim 9, characterized in that The voltage and current acquisition stability statistics module continuously monitors the voltage value or current value of the measured signal of each current channel acquired by the device, and counts the maximum and minimum values ​​within any preset time window, and calculates the difference between the maximum and minimum values ​​and records it as the jitter amplitude; calculates the percentage of the jitter amplitude of the current channel = (maximum value - minimum value) / minimum value, and evaluates the stability of voltage acquisition or current acquisition according to the percentage of the jitter amplitude of the current channel; The evaluation process is performed based on the percentage of the jitter amplitude of the current channel. If the percentage of the jitter amplitude of the current channel is smaller, it is determined that the stability of the voltage acquisition or current acquisition is better.

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