RU2570071C2 - Bioengineering system for bioimpedance control - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medical equipment. A bioengineering system for bioimpedance control consists of a computer and a mobile unit comprising active and passive electrodes and their current leads, an electronic module, a power supply battery and a wireless interface connected to an output of the electronic module and connecting the mobile unit and computer through a radio channel. A mobile unit body is configured as a hollow cylinder covered from one side with a cone-shaped cap, and on the other side - with a cylindrical lid. The body integrates the electronic module and a membrane mounted perpendicularly with a long axis of the cylindrical body, in the middle of which there is one end of an active electrode rod attached. The other end of the active electrode is integrated into an axial hole of the cone-shaped cap. An outer surface of the body bears a passive electrode representing a current-conducting ring, a button, the above wireless interface and power supply battery, a common wire of which is connected to the passive electrode and a first output of the button.

EFFECT: using the invention is expected to improve accuracy and operational efficiency of bioimpedance studies by enabling the patient to read out the information from the skin surface by him-/herself and thereby control a pressure force of the electrode, as well as by ensuring real-time bioimpedance data transmission into telecommunication networks.

2 cl, 1 tbl, 5 dwg

Description

The invention relates to medical equipment and is intended to measure the integrated electrical resistance of biological tissues and biofluids, and can also be used in electropuncture diagnostics.

A device for monitoring bioimpedance, including an electrode comprising a housing with a conical conductive tip, and a nozzle with a through axial hole, and the nozzle can be mounted on the tip [USSR Author's Certificate No. 680740, class. A61N 1/04, 1975].

A disadvantage of the known electrode is that it is structurally designed as a fixed system. As a result, the influence of a subjective factor determined by the experience and abilities of the operator is introduced into the pressure of the electrode on the skin.

Another device is known that contains active and passive electrodes, current leads of these electrodes, a spring and an active electrode body, an electronic device and an electronic device body, the active electrode being a spring-loaded rod placed in the axial channel of the housing made of insulating material, the current lead of the active electrode is connected to a spring, which in turn is connected to the rod of the active electrode [USSR Author's Certificate No. 1635995, class. A61H 39/00, 1991].

The main disadvantages of the known device is the wide variation in the pressure of the active electrode on the patient’s skin, for example, when measuring skin electrical conductivity or skin resistance to electric current at acupuncture points, as well as insufficient accuracy and reproducibility of the measurement results.

Closest to the technical nature of the proposed device is a device for electropuncture diagnostics, which contains an active and passive electrodes, their conductors, an active electrode housing, an electronic device and an electronic device housing, the active electrode of which is made in the form of a spring-loaded rod, the spring being electrically connected at one end with the rod, and the other with the active electrode conductor. The active electrode moves in the axial channel of the housing, which has travel restrictions and is made of insulating material. An active electrode holder, a cup for accommodating a capillary electrode, a capillary electrode, a ring magnet and a reed switch are also introduced into the device. The housing of the active electrode is made combined with the housing of the electronic device through a moisture-proof wall on which the reed switch is rigidly and hermetically placed with its electrical leads, and the spring concentrically covers the reed switch. The device is intended for electropunctural diagnostics in methods that use acupuncture points to measure electrical conductivity (currents) or skin resistance to electric current [Patent for the invention of the Russian Federation No. 2086176. IPC ⁶ A61B 5/05, A61H 39/00, A61N 1/04. Device for electropuncture diagnostics. Published: 08/10/1997].

The main disadvantage of the known device is the lack of telecommunication, which reduces the efficiency and accuracy of bio-impedance studies.

The second disadvantage of the prototype is the need to connect a passive electrode, which makes it difficult to use this device in a self-examination mode, when the patient is collecting data without the operator. The self-examination mode in bio-impedance studies allows not only to diagnose without the participation of a doctor, but also to significantly increase the accuracy of bio-impedance measurements due to the fact that the patient himself can objectively evaluate the pressure force of the electrode on his body and thereby significantly reduce measurement errors associated with varying electrode pressure to the surface of the skin.

The third disadvantage of the prototype is the lack of multi-frequency bio-impedancemetry, which significantly reduces the information content of bio-impedance studies.

An object of the invention is to increase the accuracy and efficiency of bio-impedance studies, which is due to the patient’s ability to independently remove information from the skin surface and thereby control the pressure force of the electrode, as well as by transmitting bio-impedance research data to telecommunication networks in real time.

The problem is solved by the fact that in a biotechnological system consisting of a computer and a mobile unit, the latter is additionally equipped with a wireless interface that communicates through the radio channel the communication of the mobile unit with the computer. The mobile unit contains active and passive electrodes and their current leads, an electronic module, a wireless interface and a battery power supply, while the housing of the mobile unit is made in the form of a hollow cylinder, closed on one side with a cone-shaped cap, and on the other hand, with a cylindrical cap inside which are located a membrane fixed perpendicular to the longitudinal axis of the cylindrical body, in the center of which is fixed one of the ends of the rod of the active electrode, while the other end is mounted in an axial hole The term cone-shaped cap, and an electronic module. On the outer surface of the housing there is a passive electrode made in the form of a conductive ring, a button, a wireless interface and a battery pack, the common wire of which is connected to the passive electrode and the first output of the button.

An electronic module of a mobile unit containing an amplifier connected to an active electrode, a resistor connected in series, the first output of which is connected to the active electrode, a second amplifier, a microcontroller, the second analog input of which is connected to the output of the first amplifier, its second digital port is connected to the second output of the button, and the third digital port - with a wireless interface, a digital-to-analog converter and a third amplifier, the output of which is connected to the second output of the resistor.

In FIG. 1 shows a structural diagram of a biotechnological system.

In FIG. 2 is a drawing of a mobile unit of a biotechnological system.

In FIG. 3 shows a diagram of a local program algorithm (local program A is selected as an example).

In FIG. Figure 4 shows the arrangement of bioactive points on the stomach meridian used by the global program for diagnosing the risk of gastrointestinal diseases to organize a dialogue with the patient.

Figure 5 shows a diagram of the algorithm of the global program for diagnosing the risk of diseases of the gastrointestinal tract.

Biotechnical system (Fig. 1) includes a mobile module 1 and a computer 2, connected via a radio channel.

The mobile module (Fig. 2) stands out of the housing 3, made in the form of a hollow cylinder, closed on one side with a conical cap 4, and on the other with a cover 5. Inside the housing there is an active electrode 6, a membrane 7, which allows the active electrode together with the conical cap 4 the electrode 6 is moved in the longitudinal direction, and the electronic module 8. On the surface of the housing 3 there is a button 9, a passive electrode 10 made in the form of a metallized ring, a wireless interface 11 and a power supply 12, the terminals of which are connected to to the input power inputs of the microchips of the electronic unit and the wireless interface, and the common wire, in addition, is connected to the passive electrode 10 and the first output of the button 9.

The electronic module (Fig. 1) contains a resistor 13 connected in series, the first output of which is connected to the active electrode 6, an amplifier 14, a microcontroller 15, the second digital port of which is connected to the second output of the button 9, and the third digital port - with a wireless interface 11, digital-to-analog a converter (DAC) 16 and an amplifier 17, the output of which is connected to the second output of the resistor 13, an amplifier 18, the input of which is connected to the active electrode 6, and the output to the second analog input of the microcontroller 15.

The device operates as follows.

For the device to work in computer 2, a global research program must be loaded. The global research program selects (offers) a medical specialist from the library of standard global research programs or his own program. Using a computer 2 through a wireless interface 11 in the microcontroller 15 is the loading of a local program of bio-impedance studies. The local program establishes a protocol for influencing a biological object with a probing current, and also determines the data format for transferring them to computer 2. After the local program is completed, further research process is controlled by a global program that implements the interaction between the patient and computer 2 through a monitor or sound card and speakers included in the computer kit 2.

After the command “start of research” appeared on the screen of the monitor, the patient takes the mobile unit 1 in the right hand so that the pads of the thumb, index and middle fingers of the right hand rest on the ring of the electrode 10, and pressing the button 9 with the index finger of the right hand confirms the computer 2 their willingness to conduct research. Upon receipt of the computer 2 readiness signal, it gives to the monitor the coordinates of the anatomical region into which the active electrode 6 needs to be installed. If necessary (depending on the implementation of the global research program) a topological picture may appear on the monitor screen, allowing the patient to navigate the anatomical features of the dislocation given body surface coordinates. After executing this command, the patient presses the button 9 to confirm the execution of the command, and the computer 2 through the wireless interface 11 proceeds to exchange information with the microcontroller 15, which executes the local program corresponding to the patient’s command specified by the global program.

The task of the local program is to set the probing current in the bioobject and read the voltage samples at the input and output of the divider formed by the current resistor 13 and the bioobject included in the divider through electrodes 6 and 10.

The installation of the probing current is performed by the microcontroller 15 by issuing at the input of the DAC 16 codes of samples of the voltage sensing. After amplification by the amplifier 17, this voltage is supplied to the input of the scaling amplifier 14 and the second output of the resistor 13. From the first output of the resistor 13, a probing voltage is supplied to the active electrode 6 and to the input of the scaling amplifier 18.

The voltages from the outputs of the amplifiers 14 and 18 are supplied to the corresponding inputs of the ADC of the microcontroller 15. The voltages from these outputs are sampled at the sampling frequency specified by the local program and processed according to the algorithms implemented by the local program.

After the local program completes the processing of the command specified by the global program, the microcontroller 15 sends a message about this to the computer 2 through the wireless interface 11, which goes into dialogue with the patient and gives him the next command.

Figure 3 presents the execution algorithm of the local program. As a rule, a local program performs the same procedure as many times as the global program “asks” it. The performed procedure measures bio-impedance at a point on the skin surface defined by the global program.

The loading of the local program A into the program memory of the microcontroller 15 is carried out in block 19. After the download is completed, program A is launched, the execution of which starts with waiting for the command to start bio-impedance measurements from the computer 2. The nature of the bio-impedance measurements depends on program A, in particular it can be quite complex bioimpedance studies aimed at studying the dispersion properties of biological tissue. The algorithm diagram presented in Fig. 3 illustrates bio-impedance studies, which consist in determining the real and imaginary components of bio-impedance at a selected point on the surface of the body at a fixed frequency and amplitude of the probing current, which is set by the local program A.

In block 19, the calculation of the samples of the sinusoid on the period of the probing current. Program A provides for the calculation of 100 samples, which are recorded in the data memory of the microcontroller 15. After calculating the samples of the sine wave of the probing current, a timer for the digital-to-analog converter 16 is set. The timer controls the output from the registers of the microcontroller 15 of the samples of the sinusoid of the probing current to the input of the digital-to-analog converter 16.

In block 20, the local program expects a command from the computer 2, confirming that the global program has instructed the patient to install the active electrode 6 at a given anatomical point on the surface of his body.

In block 21, the local program A expects the patient to press button 9, confirming that the patient has completed the prescription of the global program for installing the active electrode 6 in a given anatomical region.

и $$u{2}_{\ell }$$

, где $$\ell =\overline{\mathrm{1,200}}$$

.Block 28 sets the cycle of measuring bioimpedance in a given anatomical region. Measurements are carried out over ten cycles of the probe current frequency. The measurement process is structured in such a way that after five cycles of outputting the samples of the probe voltage to the digital-to-analog converter 16, one cycle of input of the samples of the output voltages to the microcontroller 15 is executed. As a result, twenty cycles of reading the samples of the output voltage at the electrode 6 are performed for one period of the probing current. u _k are formed in block 26. The sequence of these samples is controlled by a timer 25, which sets the frequency of the probing voltage. After five cycles of outputting samples of the probe voltage to the digital-to-analog converter 16, information is read from the outputs of amplifiers 14 and 18 (block 27). Thus, two arrays of 200 voltage samples are formed. $$u{\mathrm{one}}_{\ell }$$

and $$u{2}_{\ell }$$

where $$\ell =\overline{\mathrm{1,200}}$$

.

In blocks 28 ... 34, the amplitudes of the real URE and imaginary UIM of the voltage components on the electrode 6 are calculated:

; $$URE=\frac{\mathrm{one}}{180}{\displaystyle \sum _{\ell =21}^{200}u{2}_{\ell }\cdot u{\mathrm{one}}_{\ell }}$$

;

. $$UIM=\frac{\mathrm{one}}{180}{\displaystyle \sum _{\ell =21}^{200}u{2}_{\ell }\cdot u{\mathrm{one}}_{\ell -5}}$$

.

напряжения на выходе усилителя 14. В качестве квадратурной составляющей опорного напряжения используют смещенные на пять отсчетов (четверть периода) отсчеты $$u{1}_{\ell }$$

опорного напряжения, снимаемого с выхода усилителя 14. Отсчеты первого периода не используются при вычислении, то есть при вычислении используются 180 последних отсчетов напряжений $$u{2}_{\ell }$$

на выходе усилителя 18.As a reference voltage, samples are used $$u{\mathrm{one}}_{\ell }$$

voltage at the output of amplifier 14. As a quadrature component of the reference voltage, offset samples are used by five samples (a quarter of a period) $$u{\mathrm{one}}_{\ell }$$

reference voltage taken from the output of the amplifier 14. The samples of the first period are not used in the calculation, that is, the last 180 voltage samples are used in the calculation $$u{2}_{\ell }$$

at the output of the amplifier 18.

Active ZRE and reactive ZIM of the biological object resistance are determined in block 36. In block 35, the average current IR1 is determined through resistor R1 (a nominal value of 20 kOhm was used):

. $$IR\mathrm{one}=\frac{\mathrm{one}}{180\cdot R\mathrm{one}}{\displaystyle \sum _{\ell =21}^{200}(u{\mathrm{one}}_{\ell }-u{2}_{\ell })}$$

.

Active resistance of a bioobject is calculated as

, $$ZRE=\frac{URE}{IR\mathrm{one}}$$

,

. $$ZIM=\frac{UIM}{IR\mathrm{one}}$$

.

After calculating the real and imaginary components of the bioimpedance, the microcontroller 15 through the wireless interface 11 enters their values into the computer 2 (block 37) and confirms this event with the message "command completed" (block 38). After that, the condition for completing the execution of programs A is checked (block 39). If all the measurements provided by program A are made, then the microcontroller 15 goes to the completion of program A. Otherwise, a transition to block 20 is carried out, providing for dialogue with computer 2.

We illustrate the work of the global program on the task of predicting diseases of the gastrointestinal tract [Korenevsky N.A., Krupchatnikov R.A., Seregin S.P. Theoretical foundations of the biophysics of acupuncture with applications in biology, medicine and ecology based on fuzzy models. Kursk: OJSC IPP Kursk, 2010. 521 p.].

Prediction of these diseases is based on the analysis of active resistance in four bioactive points: E19, E21, E25 and E36.

The layout of the points selected for predicting gastric diseases is shown in FIG. four.

в риске заболеваний данного класса, которая представлена следующим решающим правилом продукционного типа:To make a decision, a confidence coefficient analysis procedure is used. $$\mathrm{TO}{\mathrm{At}}_{{\omega }_R}$$

at risk of diseases of this class, which is represented by the following decisive rule of the production type:

>0,65, ТО «Высокий риск»,IF $$\mathrm{TO}{\mathrm{At}}_{{\omega }_R}$$

> 0.65, TO "High risk",

ELSE

>0,35, ТО «Средний риск»,IF $$\mathrm{TO}{\mathrm{At}}_{{\omega }_R}$$

> 0.35, TO “Medium Risk”,

ELSE "No risk." (one)

определяется также согласно продукционному правилу:Confidence coefficient $$\mathrm{TO}{\mathrm{At}}_{{\omega }_R}$$

also determined according to the production rule:

IF { $${\left[{(R_{E19}>200\text{kOhm)}}_{}{\text{AND}}_{}{(R_{E21}>200\text{kOhm)}}_{}{\text{AND}}_{}({\mathrm{<figure-callout\; id="25"\; label="R\; E"\; filenames="00000023.png"\; state="\{\{state\}\}">R\; </figure-callout>}}_E>200\text{kOhm)}\right]}_{}$$

}, ТО $${\text{OR}}_{}\left[{(R_{E19}<80\text{kOhm)}}_{}{\text{AND}}_{}{(R_{E21}<80\text{kOhm)}}_{}{\text{AND}}_{}({\mathrm{<figure-callout\; id="25"\; label="R\; E"\; filenames="00000023.png"\; state="\{\{state\}\}">R\; </figure-callout>}}_E<80\text{kOhm)}\right]$$

}, THEN

= $${\displaystyle \sum _k{\overline{\overline{КУ}}}_k^{{\omega }_R}}$$

}{ $$\mathrm{TO}{\mathrm{At}}_{{\omega }_R}$$

= $${\displaystyle \sum _k{\overline{\overline{\mathrm{TO}\mathrm{At}}}}_k^{{\omega }_R}}$$

}

=0. (2)ELSE $$\mathrm{TO}{\mathrm{At}}_{{\omega }_R}$$

= 0. (2)

определяется путем нечеткой операции алгебраического сложения частных коэффициентов уверенности $${\overline{\overline{КУ}}}_k^{{\omega }_R}$$

: $$$$

$${\displaystyle \sum _k{\overline{\overline{КУ}}}_k^{{\omega }_R}}$$

= $$К{У}_{{\omega }_R}(k-1)+{\overline{\overline{КУ}}}_k^{{\omega }_R}(1-К{У}_{{\omega }_R}(k-1))$$

, (3)Value $${\displaystyle \sum _k{\overline{\overline{\mathrm{TO}\mathrm{At}}}}_k^{{\omega }_R}}$$

determined by the fuzzy operation of algebraic addition of partial confidence coefficients $${\overline{\overline{\mathrm{TO}\mathrm{At}}}}_k^{{\omega }_R}$$

: $$$$

$${\displaystyle \sum _k{\overline{\overline{\mathrm{TO}\mathrm{At}}}}_k^{{\omega }_R}}$$

= $$\mathrm{TO}{\mathrm{At}}_{{\omega }_R}(k-\mathrm{one})+{\overline{\overline{\mathrm{TO}\mathrm{At}}}}_k^{{\omega }_R}(\mathrm{one}-\mathrm{TO}{\mathrm{At}}_{{\omega }_R}(k-\mathrm{one}))$$

, (3)

; $$k=\overline{\mathrm{1,4}}$$

; $$\mathrm{TO}{\mathrm{At}}_{{\omega }_R}(k)={\displaystyle \sum _{i=\mathrm{one}}^k{\overline{\overline{\mathrm{TO}\mathrm{At}}}}_i^{{\omega }_R}}$$

; $$k=\overline{1.4}$$

;

, $$\mathrm{TO}{\mathrm{At}}_{{\omega }_{\mathrm{TO}}}(\mathrm{one})={\overline{\overline{\mathrm{TO}\mathrm{At}}}}_{\mathrm{one}}^{{\omega }_R}$$

,

$$К{У}_{{\omega }_{К}}(k)=0приk<1$$

. $$$$

$$\mathrm{TO}{\mathrm{At}}_{{\omega }_{\mathrm{TO}}}(k)=0PR\mathrm{and}k<\mathrm{one}$$

.

.Partial confidence coefficients are determined for each biologically active point, depending on the value of active resistance in it according to table 1. Resistance in biologically active points are indicated $$R_{E19},R_{E21},{\mathrm{<figure-callout\; id="25"\; label="R\; E"\; filenames="00000023.png"\; state="\{\{state\}\}">R\; </figure-callout>}}_E,R_{E36}$$

.

Table 1

Private confidence factors for predicting gastric diseases

Class BAT Resistance ranges, kOhm > 500 400 ...
500 300 ...
399 200 ...
299 one hundred...
199 90 ...
99 80 ...
89 70 ...
79 60 ...
69 fifty...
59 <50 ω E19 0.6 0.5 0.35 0.2 0 0 0.2 0.3 0.45 0.55 0.6 E21 0.65 0.6 0.5 0.25 0 0 0.2 0.35 0.5 0.6 0.65 E25 0.65 0.6 0.5 0.25 0 0 0.25 0.5 0.6 0.65 0.7 E36 0.7 0.6 0.45 0.2 0 0 0.25 0.5 0.65 0.8 0.9

The decision algorithm according to this global program is presented in figure 5.

In block 41, the local program is loaded into the microcontroller 15. Blocks 41 and 42 carry out a dialogue with the patient when measured at the first point E19. In block 44, data is transmitted at the first point from mobile block 1 to computer 2. Blocks 45 ... 53 perform similar procedures for the remaining three points E21, E25, and E36.

In block 53, the determination of particular confidence coefficients is performed according to Table 1, and in block 55, the total confidence coefficient is calculated according to the recurrence formula (3).

The final value of the confidence coefficient is determined according to the product (2) in block 56, and the final diagnosis is made according to the product (1) in block 57.

Thus, using the mobile block of the biotechnological bioimpedance monitoring system, the patient has the opportunity to independently remove diagnostic information from the skin surface and, through the use of telecommunication channels, can quickly obtain information about the group of suspected diagnoses with corresponding risk factors.

Claims (2)

1. Biotechnological system of bioimpedance control, consisting of a computer and a mobile unit containing active and passive electrodes and their current leads, an electronic module, a battery power supply and a wireless interface connected to the output of the electronic module and communicating via a radio channel between the mobile unit and the computer, characterized in that the housing of the mobile unit is made in the form of a hollow cylinder, closed on one side with a cone-shaped cap, and on the other hand, with a cylindrical cap, inside which the membrane is located, akreplennaya perpendicular to the longitudinal axis of the cylindrical housing, in which center one end of the active electrode rod is fixed, while its other end is mounted in the conical axial bore of the cap, and an electronic module; and on the outer surface of the housing there is a passive electrode made in the form of a conductive ring, a button, a wireless interface and a battery pack, the common wire of which is connected to the passive electrode and the first output of the button. 2. The biotechnological system according to claim 1, characterized in that the electronic module of the mobile unit contains a first amplifier connected to the active electrode, a resistor connected in series, the first output of which is connected to the active electrode, a second amplifier, a microcontroller, the second analog input of which is connected to the output the first amplifier, its second digital port is connected to the second output of the button, and the third digital port is connected to a wireless interface, a digital-to-analog converter and a third amplifier, the output of which is connected n to the second terminal of the resistor.

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