Summary of the invention
The purpose of this invention is to provide a kind of nonlinear fetal heart rate surveillance instrument, it can not only show, write down and store the heart rate signal of fetus by computer real-time, and can adopt nonlinear dynamic analysis method (correlation dimension, maximum lipschitz exponent, approximate entropy, power spectrum, auto-correlation function and cross-correlation function) express fetus in the intravital different health status of mother.
The present invention adopts the ultrasonic doppler pick off to extract the cardiechema signals of fetus, utilize the fetal heart rate signal extractor from the audio signal of fetal heart sound, to extract the envelope of audio signal then, and the envelope of audio signal is converted to corresponding with it square-wave signal, makes a square-wave signal corresponding with a fetal heartbeat; To pass to PC6360 mould/number incoming interface card by the square-wave signal that the fetal heart rate signal extractor obtains, finish the mould/number conversion of fetal heart rate signal, and pass to NONLINEAR CALCULATION machine analysis processor, calculate instantaneous fetal heart frequency by NONLINEAR CALCULATION machine analysis processor according to the interval of adjacent twice square wave, NONLINEAR CALCULATION machine analysis processor further can be finished the data of instantaneous fetal heart rate signal and the real-time demonstration of figure, reappear, and the storage of data, the nonlinear kinetics calculation of parameter part of NONLINEAR CALCULATION machine analysis processor can be calculated the correlation dimension of fetal heart rate signal, maximum lipschitz exponent, entropy, complexity, power spectrum, auto-correlation function and cross-correlation function.
The doctor can make diagnostic recommendations according to the different distributions interval of nonlinear characteristic amount and the corresponding relation of different foetus health situations.
Technical solution of the present invention:
As shown in Figure 1, at first extract the cardiechema signals of fetus by the ultrasonic doppler pick off, utilize fetal heart rate signal extractor (its circuit theory diagrams are shown in Fig. 2-8) from the audio signal of fetal heart sound, to extract the envelope (shown in Fig. 2-7) of audio signal, make that the envelope of a fetal heart sound signal is corresponding with a fetal heartbeat, behind zero balancing circuit (Fig. 8), the envelope that makes a cardiechema signals is corresponding to a square-wave signal; The square-wave signal that the fetal heart rate signal extractor is obtained passes to PC6360 mould/number interface card, finish the mould/number conversion of fetal heart rate signal and pass to NONLINEAR CALCULATION machine analysis processor, calculate data and the pictorial display that instantaneous fetal heart frequency further can be finished instantaneous fetal heart rate signal simultaneously by NONLINEAR CALCULATION machine analysis processor according to the interval of adjacent twice square wave, reappear, and the storage of data, NONLINEAR CALCULATION machine analysis processor can calculate the correlation dimension of fetal heart rate signal, maximum lipschitz exponent, entropy, complexity, power spectrum, auto-correlation function and cross-correlation function.The doctor can utilize the different distributions of nonlinear kinetics parameter of Fetal Instantaneous Heart Rate signal and the corresponding relation of foetus health situation, provides diagnostic recommendations.
Related description about circuit theory diagrams:
At first extract the fetal heart sound signal by the ultrasonic multispectral probe of reining in, what connect subsequently is by resistor R
1, capacitor C
1And the cable follower (as shown in Figure 2) of operational amplifier μ A741 composition, wherein resistor R
1Can adopt rheostat, what be connected with the pin 6 of operational amplifier μ A741 is by resistor R
2, R
3, R
4, R
5With the amplifying circuit (as shown in Figure 2) of operational amplifier μ A741 composition, wherein resistor R
5Can adopt rheostat, the amplification of amplifier is adjustable within the specific limits like this.Operational amplifier μ A741 pin of chip 6 is connected with the pin 9 of multiplier MC1495.By resistance R
13, R
14, R
15, R
16, Zener diode D
1, D
2And the square-wave generator (as shown in Figure 3) of operational amplifier μ A741 composition, operational amplifier μ A741 pin of chip 6 is connected with the pin 4 of multiplier (as shown in Figure 4) MC1495.The pin 1 of multiplier MC1495 passes through resistor R
8Be connected with+15V power supply, pin 2 passes through resistor R
10Be connected with+15V power supply, pin 3 passes through resistor R
7Ground connection is connected to resistor R between pin 5 and the pin 6
12, pin 7 connects-the 15V power supply, and pin 8 ground connection are connected with resistor R between pin 10 and the pin 11
11, pin 12 ground connection, pin 13 passes through resistor R
6Be connected with ground, pin 14 passes through resistor R
9Be connected pin 14 direct ground connection simultaneously, pin 2 and by resistor R with+15V power supply
17, R
19, R
21, R
23, R
25, R
27, R
29, R
31, capacitor C
3, C
5, C
7, C
9, C
11, C
12, C
14And the mid frequency that 4 operational amplifier μ A741 chips are formed is the 8 rank chebyshev low-pass filters (as shown in Figure 5) of 5Hz, the 3rd the operational amplifier μ A741 chip pin 6 of wave filter with by resistor R
18, R
20, R
22, R
24, R
26, R
28, R
30, R
32, capacitor C
4, C
6, C
8, C
10, C
22, C
13, C
25, C
16And the mid frequency that 4 operational amplifier μ A741 chips are formed is the 8 rank chebyshev low-pass filters (as shown in Figure 6) of 5Hz, the 3rd the operational amplifier μ A741 chip pin 6 of wave filter with by capacitor C
17, resistor R
33The zero crossing circuitry of forming (as shown in Figure 7) connects, zero crossing circuitry subsequently with by resistor R
34, R
35, R
36, R
37, R
38, R
39, R
40, R
41, capacitor C
8, C
9, C
10, C
11, C
23, C
24, C
26, C
27 reachThe mid frequency that 4 operational amplifier μ A741 chips are formed is the 8 rank chebyshev low-pass filters (as shown in Figure 7) of 5Hz, the 3rd μ A741 pin of chip 6 of wave filter and resistor R
42, R
43, R
44And the amplifier (as shown in Figure 8) formed of operational amplifier μ A741 chip, the pin 6 of amplifier is connected with the pin 3 of operational amplifier μ A741, pin 2 ground connection of this operational amplifier μ A741, pin 6 and by resistor R
45, R
46, diode D
3, D
4,, capacitor C
28The voltage limiter circuit of forming (as shown in Figure 8), resistor R
46, capacitor C
28The junction, link with the digital input channel of PC6360 mould/number interface card.
By the ultrasonic multispectral fetal heart sound signal that probe collects of reining in, at first pass through the cable follower, be amplifier then, then cardiechema signals and 95Hz square-wave signal carry out coherent detection, signal behind the coherent detection, continuously by 28 rank chebyshev low-pass filters, then through zero crossing circuitry, again through 8 rank chebyshev low-pass filters, then signal is amplified, cross zero balancing then, the voltage amplitude limit is after the digital input channel of PC6360 mould/number interface card inserts NONLINEAR CALCULATION machine analysis processor.Use NONLINEAR CALCULATION machine analysis processor to carry out date processing and analysis at last.
Described NONLINEAR CALCULATION machine analysis processor is equipped with work circle by the nonlinear dynamic analysis software kit of the human-computer interaction interface of VB high-level language establishment and the establishment of VC high-level language, and use TC high-level language has been worked out the analysis software in the nonlinear dynamic analysis software kit.
Analysis software of the present invention is by two-dimensional phase Space Reconstruction program unit, the power spectrum program unit, the time series program unit, the approximate entropy program unit, the correlation function program unit, the correlation dimension program unit, maximum lipschitz exponent unit program and vc boundary element program are formed, at first, open this program of vc interface, what be presented in ours in front is a dialog box, 7 programs is arranged: two-dimensional phase Space Reconstruction program in the drop-down menu of his the inside, the power spectrum program, the time series program, approximate entropy program, correlation function program, the correlation dimension program, maximum lipschitz exponent program.Correlation function program in these 7 program the insides of operation is a parameter for correlation dimension and maximum lipschitz exponent; So, before operation correlation dimension program and maximum lipschitz exponent program, be to move the correlation function program earlier;
Data doctor according to the said procedure gained can analyze fetal heart frequency exactly, the health status of analytical judgment fetus;
The flow process of following each program of division:
The interface program that vc++ weaves into begins to build an engineering.In Dialog, add a dialog box then.Add control (drop-down menu, three buttons, paste bitmap) on Dialog, in the content that the CmyDlg class is added 8 variablees and its representative, respectively top control is added responder, program just is through with like this:
The program flow diagram of approximate entropy is at first opened data file to be analyzed, and it can calculate the total total number of data of this file then; Then, read data number N to be analyzed from file, calculate standard deviation: σ, calculate: 0.2* σ → L, input embeds dimension m, because algorithm requirement itself is 2.The phase space of reconstruct m n dimensional vector n, the distance that calculates any two points in this space is paid count less than the number of L, so approximate entropy is exactly:
Approximate entropy:
And
The program flow diagram of correlation dimension is at first opened data file to be analyzed, and it can calculate the total total number of data of this file then; Then, read data number n to be analyzed from file and be put into another data file 1, import initial dimension m then, the step-length mk of growth and retardation k.When m<md enters Do statement, in this circulation the inside, at first want the phase space (its algorithm is identical with the flow chart of two-dimensional phase Space Reconstruction) of reconstruct m n dimensional vector n to be put into two data files 2 respectively, in 3, obtain depositing in the file 4 of counting in the file 2,3 apart from d, just go into next circulation then, input start radius A, the radius step-length B of growth, initialization s is 0.Just go into circulation when r<C: sense data and r ratio from file 4, if d<r, s just adds 1, is just to add 0 greater than r.Can obtain one group of lnC (r) and ln (r) like this under this condition of r<C, the figure that draws then, the slope of this figure are exactly the dimension D of requirement.M adds mk and can obtain a dimension D again then, can obtain one group like this; (jaggies in the flow chart and straight line do not intersect)
The power spectrum program flow diagram is at first opened data file to be analyzed, and it can calculate the total total number of data of this file then; Then, reading data number n to be analyzed from file is put into another data file 1.Be put in the data file 2 as auto-correlation function with this n number, it has been exactly the figure of power spectrum that the data that the data in the reuse 2 obtain as Fourier transform are drawn; (autocorrelative algorithm is exactly the algorithm of the flow chart of correlation function program)
The program flow diagram of correlation function is at first opened data file to be analyzed, and it can calculate the total total number of data of this file then; Then, reading data number N to be analyzed from file is put into the data file 1.Input Nb value (wanting the number of picture point), the m assignment is 0, (N-Nb) composes and gives T.If m<Nb enters outer circulation, be summation variable s assignment 0 then.Enter internal recycle, j is the internal recycle variable, and initial value is 0, j<T.Calculate two retardations and multiply each other, revest s with s and product summation, internal recycle is over and just can obtains a s value.Draw as horizontal, vertical coordinate with m and s.(if calculate from time series reading is exactly self correlation, if be exactly cross-correlation from two different time series readings.First minimum of figure is exactly a time delay)
The program flow diagram of two-dimensional phase Space Reconstruction, start program can be inquired the data file name that you are to be analyzed, can calculate total what data of this file then; Then, read you from this file and want the data number n analyzed, then it is put into again in the data file 1,, embed dimension initial value m=2 with the input delay variate-value, retardation k, initializing variable b is 0, calculates number a little; Then be two Do statements.At first, i is outer circulation, and j is that circulation, and reading is paid variable y from file 1, works as i, when j, k, b, m satisfy condition shown in the block diagram, and just y is write in the file 2 during b=0, when b=1, just write in the file 3, so just can not draw with the data in 2,3 are non-as horizontal vertical coordinate.(top jaggies and straight line do not intersect)
The program flow diagram of temporal sequence, this is the program flow diagram of a calculating time delay amount, at first opens data file to be analyzed, it can calculate the total total number of data of this file then.Then, input starting point vb puts ve finally, calculates: the ve-vb → n that always counts, can draw with that, and abscissa is a natural number, vertical coordinate is the number that reads out from data file.
The program flow diagram of maximum lipschitz exponent is at first opened data file to be analyzed, and it can calculate the total total number of data of this file then.Then, read data number n to be analyzed from file and be put into another data file 1, import initial dimension m=mb then, the step-length mp of growth and retardation k.When m<md enters Do statement, in this circulation the inside, at first want the phase space of reconstruct m n dimensional vector n and it is put in the data file 2, selected 1 j (<n-(m-1) * k), find out its nearest neighbor point J ' then, and calculate it apart from d (0), through τ calculate once more after the time this 2 apart from d (τ), draw d (τ) with the change curve of τ and to ask its slope value be exactly maximum lipschitz exponent value, once more m is added that step-length mp Do statement place calculates.
Good effect of the present invention is:
(1) clinicing aspect: can instruct the clinician to pass through the observation of instantaneous fetal heart frequency and the health status of analytical judgment fetus (clinician is according to the baseline and the direct judgement of the fluctuation foetus health thereof of fetal heart frequency monitoring at present) according to the nonlinear kinetics principle;
(2) master plan fertility: have very profound significance with research to improving the population health situation, improving the health of the people by analysis to the foetus health situation.
(3) low price, market prospect is good, can hospital above county level promote the use of in the whole nation through secondary development.
The present invention can promote the use of at hospital clinical above county level, can be in institution of higher learning's clinical medicine teaching; Teaching research and scientific research research field are promoted the use of, and economic benefit and social benefit are obvious.
The specific embodiment
Embodiment:
The present invention is made up of four parts:
1. ultrasonic doppler pick off;
2. the fetal heart rate signal extractor of forming by analog circuit and digital circuit;
3. the fetal heart rate signal extractor connects with PC6360 mould/number interface card, finishes the mould/number conversion of fetal heart rate signal;
4. NONLINEAR CALCULATION machine analysis processor;
Further narrate the present invention below in conjunction with accompanying drawing, described fetal heart sound signal is gathered by the ultrasonic multispectral probe of reining in, and what connect subsequently is by resistor R
1, capacitor C
1And the cable follower (as shown in Figure 2) of operational amplifier μ A741 composition, wherein resistor R
1Can adopt variable resistance, what be connected with the pin 6 of the operational amplifier μ A741 of cable follower is by resistor R
2, R
3, R
4, R
5With the amplifying circuit (as shown in Figure 2) that operational amplifier μ A741 forms, wherein R5 can use variable resistance, and the amplification of amplifier is adjustable within the specific limits like this; Cardiechema signals is imported the pin 9 of multiplier MC1495 through after amplifying, and cardiechema signals and square-wave signal carry out coherent detection; By resistor R
13, R
14, R
15, R
16, Zener diode D
1, D
2And the square-wave generator (as shown in Figure 3) of operational amplifier μ A741 composition, the pin 6 of operational amplifier μ A741 is connected with the pin 4 of multiplier MC1495 (as shown in Figure 4); The pin 1 of multiplier MC1495 passes through resistor R
8Be connected with+15V power supply, pin 2 passes through resistor R
10Be connected with+15V power supply, pin 3 passes through resistor R
7Ground connection is connected to resistor R between pin 5 and the pin 6
12, pin 7 connects-the 15V power supply, and pin 8 ground connection are connected with resistor R between pin 10 and the pin 11
11, pin 12 ground connection, pin 13 passes through resistor R
6Be connected with ground, pin 14 passes through resistor R
9Be connected with+15V power supply, pin 14 direct ground connection obtain the cardiechema signals envelope behind the coherent detection simultaneously; Pass through by resistor R subsequently
17, R
19, R
21, R
23, R
25, R
27, R
29, R
31, capacitor C
3, C
5, C
7, C
9, C
11, C
12, C
15, C
14And the mid frequency that 4 operational amplifier μ A741 form is the 8 rank chebyshev low-pass filters (as shown in Figure 5) of 5Hz, the pin 6 of the 3rd operational amplifier μ A741 of wave filter with by resistor R
18, R
20, R
22, R
24, R
26, R
28, R
30, R
32, capacitor C
4, C
6, C
8, C
10, C
22, C
13, C
25, C
16The mid frequency that reaches 4 operational amplifier μ A741 chips compositions is the 8 rank chebyshev low-pass filters (as shown in Figure 6) of 5Hz, and signal is by pin 6 outputs of the 3rd operational amplifier, through obtaining intact hear sounds envelope after twice low-pass filtering; Subsequently signal is carried out zero passage, remove flip-flop; Zero crossing circuitry (as shown in Figure 7) is by capacitor C
17, resistor R
33Form; Subsequently with by resistor R
34, R
35, R
36, R
37, R
38, R
39, R
40, R
41, capacitor C
8, C
9, C
10, C
11, C
23, C
24, C
26, C
27The mid frequency that reaches 4 operational amplifier μ A741 compositions is that the 8 rank chebyshev low-pass filters 9 (as shown in Figure 7) of 5Hz connect, and removes the interference of being introduced by zero passage, pin 6 and the resistor R of the 3rd operational amplifier μ A741 of wave filter
42, R
43, R
44And the amplifier (as shown in Figure 8) that operational amplifier μ A741 forms, signal is amplified; Obtain the square-wave signal of hear sounds envelope after the signal process zero balancing (as shown in Figure 8) after the amplification, through voltage limiter circuit (as shown in Figure 8), remove the negative loop in the signal, obtain the TTL ripple, link with the digital input channel of PC6360 mould/number interface card subsequently and insert NONLINEAR CALCULATION machine analysis processor.By the interval of NONLINEAR CALCULATION machine analysis processor, calculate instantaneous fetal heart frequency according to adjacent twice square wave of record.
Aforementioned operational amplifier can replace with the operational amplifier of high integration such as NE532.
The circuit elements device parameters:
R
1=200kΩ;R
2=10kΩ;R
3=20kΩ;R
4=20kΩ;R
5=10kΩ;C
1=120pF;R
6=12kΩ;R
7=12kΩ;R
8=3kΩ;
R
9=R
10=20kΩ;R
11=R
12=10kΩ;R
13=R
14=20kΩ;
R
15=48.8kΩ;R
16=473kΩ;
R
17=R
19=R
21=R
23=R
25=R
27=R
29=R
31=100KΩ;
C
3=0.15μF;C
5=0.033μF;C
7=2.2μF;C
9=0.15μF;
C
11=0.047μF;C
12=0.047μF;C
15=0.01μF;C
14=10μF;
R
18=R
20=R
22=R
24=R
26=R
28=R
30=R
32=100kΩ;
C
4=0.15μF;C
6=0.033μF;C
8=2.2μF;C
10=0.15μF;C
22=0.047μF;C
13=0.047μF;C
25=10μF;C
16=0.01μF;C
17=0.1μF;R
33=410Ω;
R
34=R
35=R
36=R
37=R
38=R
39=R
40=R
41=100kΩ;
C
8=0.15μF;C
9=0.033μF;C
10=2.2μF;C
11=0.15μF;C
23=0.047μF;C
24=0.047μF;C
26=10μF;C
27=0.01μF;
R
42=5kΩ;R
43=7.5kΩ;R
44=15kΩ;R
45=470kΩ;R
46=1.5kΩ;C
28=0.01μF。
Wherein resistor all adopts fixed carbon resister, capacitor C
14, C
25, C
26Be electrochemical capacitor, all the other electric capacity are ceramic condenser, diode D
1, D
2, D
3, D
4Be the 5.5V Zener diode, amplifier is operational amplifier μ A741.We also can for example use operational amplifier NE5532 to wait substitution operation amplifier μ A741 with the higher operational amplifier of integrated level.
The operation interface of nonlinear fetal heart rate surveillance instrument, be with the establishment of Visual-Basic high-level language, form by three parts: at first be one and eject the interface, be a patient information input interface then, can import patient's name, age, case number and pregnant all numbers, be working interface at last.
Working interface can be realized following function:
(1) the real-time demonstration and the record of instantaneous fetal heart rate signal, 40-240bpm;
(2) alarm indicator of instantaneous fetal heart rate signal promptly is lower than 120bpm when instantaneous fetal heart frequency value, or is higher than 160bpm, and when continuing 20 seconds on the interface amber light or red light bright;
(3) has the data-storing function;
(4) has the reproduction capability of data and figure.
Nonlinear fetal heart rate surveillance instrument uses the VC high-level language to work out the working interface of nonlinear dynamic analysis software kit, and uses the TC high-level language to work out calculation procedure; Can calculate the correlation dimension of fetal heart rate signal, maximum lipschitz exponent, approximate entropy, power spectrum, auto-correlation function and cross-correlation function.Utilize the corresponding relation of nonlinear kinetics parameter and different foetus health situations, provide diagnostic recommendations.
Operating process of the present invention: ultrasonic Doppler probe is positioned over anemia of pregnant woman's abdominal part, extract the fetal heart sound signal by ultrasonic Doppler probe, to pass to the fetal heart rate signal extractor of forming by analog circuit and digital circuit by the fetal heart sound signal that the ultrasonic doppler sensor probe extracts, the fetal heart rate signal extractor is connected with PC6360 mould/number interface card, finish the mould/number conversion of fetal heart rate signal, go out instantaneous fetal heart frequency by COMPUTER CALCULATION, and be presented on the computer display.Computer was stored the Fetal Instantaneous Heart Rate data automatically after detection finished, and can do nonlinear dynamic analysis to instantaneous fetal heart frequency data by the program that the nonlinear kinetics software kit provides at last.At first, open this program of vc interface, what be presented in ours in front is a dialog box, 7 programs is arranged: two-dimensional phase Space Reconstruction program in the drop-down menu of his the inside, the power spectrum program, time series program, approximate entropy program, the correlation function program, correlation dimension program, maximum lipschitz exponent program.Correlation function program in these 7 program the insides of operation is a parameter for correlation dimension and maximum lipschitz exponent; So, before operation correlation dimension program and maximum lipschitz exponent program, be to move the correlation function program earlier;
Data doctor according to the said procedure gained can analyze fetal heart frequency exactly, the health status of analytical judgment fetus.