CN115153469A - Human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fiber - Google Patents
Human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fiber Download PDFInfo
- Publication number
- CN115153469A CN115153469A CN202210873107.1A CN202210873107A CN115153469A CN 115153469 A CN115153469 A CN 115153469A CN 202210873107 A CN202210873107 A CN 202210873107A CN 115153469 A CN115153469 A CN 115153469A
- Authority
- CN
- China
- Prior art keywords
- micro
- pulse
- blood pressure
- monitoring device
- self
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 58
- 238000012806 monitoring device Methods 0.000 title claims abstract description 30
- 230000036772 blood pressure Effects 0.000 claims abstract description 69
- 238000012545 processing Methods 0.000 claims abstract description 23
- 230000003287 optical effect Effects 0.000 claims abstract description 22
- 238000000034 method Methods 0.000 claims description 19
- 239000012528 membrane Substances 0.000 claims description 18
- 239000008280 blood Substances 0.000 claims description 17
- 210000004369 blood Anatomy 0.000 claims description 17
- 230000005540 biological transmission Effects 0.000 claims description 14
- 230000008569 process Effects 0.000 claims description 12
- 239000004205 dimethyl polysiloxane Substances 0.000 claims description 11
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 claims description 11
- 210000001367 artery Anatomy 0.000 claims description 10
- 230000035487 diastolic blood pressure Effects 0.000 claims description 10
- 230000035488 systolic blood pressure Effects 0.000 claims description 10
- 210000004204 blood vessel Anatomy 0.000 claims description 9
- 230000008859 change Effects 0.000 claims description 8
- 239000002121 nanofiber Substances 0.000 claims description 8
- 239000011521 glass Substances 0.000 claims description 6
- 238000001361 intraarterial administration Methods 0.000 claims description 6
- -1 polydimethylsiloxane Polymers 0.000 claims description 5
- 230000009471 action Effects 0.000 claims description 3
- 238000003286 fusion draw glass process Methods 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 claims description 2
- 230000007480 spreading Effects 0.000 claims description 2
- 238000003892 spreading Methods 0.000 claims description 2
- 235000013870 dimethyl polysiloxane Nutrition 0.000 claims 3
- 206010020772 Hypertension Diseases 0.000 claims 1
- 230000001631 hypertensive effect Effects 0.000 claims 1
- 230000009466 transformation Effects 0.000 claims 1
- 238000005259 measurement Methods 0.000 abstract description 11
- 230000035485 pulse pressure Effects 0.000 abstract description 3
- 238000005452 bending Methods 0.000 description 6
- 238000012544 monitoring process Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000010989 Bland-Altman Methods 0.000 description 4
- 238000001514 detection method Methods 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 238000001228 spectrum Methods 0.000 description 3
- 238000009530 blood pressure measurement Methods 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 208000026106 cerebrovascular disease Diseases 0.000 description 2
- 238000007872 degassing Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 125000000118 dimethyl group Chemical group [H]C([H])([H])* 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 239000009136 dragon's blood Substances 0.000 description 2
- 230000005684 electric field Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 230000036541 health Effects 0.000 description 2
- 208000015210 hypertensive heart disease Diseases 0.000 description 2
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 2
- 229910052753 mercury Inorganic materials 0.000 description 2
- 239000011259 mixed solution Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 229920005573 silicon-containing polymer Polymers 0.000 description 2
- 239000010409 thin film Substances 0.000 description 2
- 206010005746 Blood pressure fluctuation Diseases 0.000 description 1
- 208000024172 Cardiovascular disease Diseases 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000003745 diagnosis Methods 0.000 description 1
- 235000005911 diet Nutrition 0.000 description 1
- 230000000378 dietary effect Effects 0.000 description 1
- 230000006806 disease prevention Effects 0.000 description 1
- 230000002526 effect on cardiovascular system Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000007726 management method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 229920002379 silicone rubber Polymers 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- 238000004148 unit process Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/021—Measuring pressure in heart or blood vessels
- A61B5/02108—Measuring pressure in heart or blood vessels from analysis of pulse wave characteristics
- A61B5/02125—Measuring pressure in heart or blood vessels from analysis of pulse wave characteristics of pulse wave propagation time
-
- G—PHYSICS
- G16—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
- G16H—HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA
- G16H30/00—ICT specially adapted for the handling or processing of medical images
- G16H30/20—ICT specially adapted for the handling or processing of medical images for handling medical images, e.g. DICOM, HL7 or PACS
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Public Health (AREA)
- Cardiology (AREA)
- Medical Informatics (AREA)
- Surgery (AREA)
- Animal Behavior & Ethology (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Biophysics (AREA)
- Molecular Biology (AREA)
- Physiology (AREA)
- Pathology (AREA)
- Vascular Medicine (AREA)
- Physics & Mathematics (AREA)
- Veterinary Medicine (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Radiology & Medical Imaging (AREA)
- Epidemiology (AREA)
- Primary Health Care (AREA)
- Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
Abstract
A human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fibers relates to the technical field of optical measurement and aims to solve the problems of high cost, poor accuracy and difficulty in realization of the existing optical pulse and blood pressure monitoring device. The device comprises a sensing diaphragm, a laser, a light splitting element, a photoelectric detector, a data acquisition card, a signal processing unit and a blood pressure calculating unit; the sensing diaphragm is used for collecting pulse information; the laser is used for emitting output optical signals, and the output optical signals are returned by the sensing diaphragm together with pulse information to generate self-mixing interference signals with an original optical field; the photoelectric detector is used for converting the optical signal into a continuous analog signal and sending the continuous analog signal to the data acquisition card; the data acquisition card is used for converting the analog signals into digital signals and transmitting the digital signals to the signal processing unit; the signal processing unit is used for processing the digital signals to obtain pulse wave information, and the blood pressure calculating unit is used for calculating a human blood pressure value. The device of the invention is a human body multi-parameter monitoring device with good application prospect.
Description
Technical Field
The invention relates to the technical field of optical measurement, in particular to a human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fibers.
Background
With the continuous improvement of living standards and the change of dietary structures of people, the threat of cardiovascular and cerebrovascular diseases to human health is becoming more serious, and self-management of health and prevention of diseases through continuous monitoring of pulse information and blood pressure in daily life becomes more important. Therefore, the continuous monitoring of the pulse wave and the blood pressure has important clinical value for the prevention and the diagnosis of the cerebrovascular diseases in the daily life center. The traditional measuring device mostly adopts a mercury sphygmomanometer and an electronic sphygmomanometer, the mercury sphygmomanometer needs to measure the value by personal experience due to artificial auditory and visual errors when monitoring blood pressure and pulse, has higher requirement on an operator, is generally a doctor or an experienced nurse, and is not suitable for common people to measure by themselves; the electronic sphygmomanometer is more convenient to use, but the cuff is also required to be worn for intermittent inflation, so that the measurement operation is inconvenient.
At present, the application of photon sensing technology to monitoring human blood pressure and pulse is receiving attention of researchers, however, devices obtained through current research have the problems of high development cost, poor accuracy, lack of comfort, difficulty in implementation and the like, and even have potential safety hazards due to the problems of poor bending and ductility of used materials, lack of elasticity, easiness in breaking and the like, so that the development of an optical human blood pressure and pulse detection device which is low in cost, high in accuracy, comfortable and feasible is urgently needed.
Disclosure of Invention
The technical problem to be solved by the invention is as follows:
the existing optical pulse and blood pressure monitoring device has the problems of high cost, poor accuracy and difficult realization.
The technical scheme adopted by the invention for solving the technical problems is as follows:
the invention provides a human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fibers, which comprises a sensing diaphragm, a laser, a photoelectric detector, a data acquisition card, a signal processing unit and a blood pressure calculating unit, wherein the sensing diaphragm is arranged on the outer side of the sensing diaphragm;
the sensing diaphragm comprises a micro-nano optical fiber and a flexible diaphragm, the micro-nano optical fiber is embedded in the flexible diaphragm, the sensing diaphragm is used for collecting pulse information, and the flexible diaphragm is deformed due to pulse vibration to change the refraction slope of the micro-nano optical fiber;
the laser is connected with one end of the micro-nano optical fiber through the optical fiber, the other end of the micro-nano optical fiber is provided with a reflection end, the laser can emit an output optical signal with a certain wavelength under the action of driving current, the output optical signal passes through the pulse vibration part and is reflected by the reflection end, and an optical signal carrying pulse information returns to the inside of a laser resonant cavity to generate a self-mixing interference signal with an original optical field;
the photoelectric detector is arranged in the laser and used for converting the self-mixing interference signal into a continuous analog signal and sending the continuous analog signal to the data acquisition card;
the data acquisition card is connected with the photoelectric detector, is a USB dynamic signal acquisition card and is used for converting received analog signals into digital signals and transmitting the digital signals to the signal processing unit;
the signal processing unit is used for processing the received digital signals to obtain pulse wave information and transmitting the pulse wave information to the blood pressure calculating unit;
the blood pressure calculating unit is used for calculating a human blood pressure value according to the pulse wave information.
Furthermore, the micro-nano optical fiber is a biconical micro-nano optical fiber, the length of the conical regions at two ends of the biconical micro-nano optical fiber is 15mm, the length of the waist region is 12mm, and the diameter of the waist region is 1.8 mu m.
Further, the flexible membrane is a polydimethylsiloxane membrane.
Further, the length of the sensing diaphragm is 7.5cm, and the width of the sensing diaphragm is 2.2cm.
Further, the specific implementation process of embedding the micro-nano optical fiber in the flexible diaphragm is as follows: spreading a proper amount of dimethyl silicone polymer subjected to degassing treatment on a glass sheet with a certain size, embedding the micro-nano optical fiber into the dimethyl silicone polymer, curing the micro-nano optical fiber to form a membrane, and taking the membrane off the glass sheet, namely embedding the micro-nano optical fiber into a flexible membrane.
Further, the curing treatment is performed under conditions of heating at a temperature of 80 ℃ for 20 minutes.
Further, the preparation method of the biconical micro-nano optical fiber is to adopt a fusion drawing method to prepare the biconical micro-nano optical fiber through a tapering machine.
Further, the signal processing unit is configured to process the received digital signal to obtain pulse wave information, and the specific implementation process includes: and processing the digital signal by LabVIEW software to obtain a pulse oscillogram, and converting the pulse oscillogram into a pulse spectrogram by Fourier transform to obtain pulse waveform information and frequency information.
Further, the blood pressure calculating unit is used for calculating a human blood pressure value according to the pulse wave information, and the specific implementation process is as follows:
determining the time span from the main wave peak value to the heavy vibration wave peak value according to the pulse spectrogram, wherein the time span is expressed as pulse transmission time PTT, and the relationship between the pulse transmission time PTT and the pulse wave velocity PWV is as follows:
wherein, L represents the length of a blood vessel through which the pulse wave passes;
according to the Brawell-hill equation, the pulse wave velocity PWV can be represented by the blood density ρ and the arterial blood volume v, specifically:
where V is the intra-arterial blood volume, dV is the change in intra-arterial blood volume, dP is the blood pressure difference between the systolic pressure SBP and the diastolic pressure DBP, in mmHg, and dP can be expressed as:
dP＝SBP-DBP (3)
the pulse wave velocity PWV can therefore be expressed as:
from equation (1) and equation (4) we can obtain:
on the other hand, the pulse wave velocity PWV can be expressed by the Moens-korteweg equation:
wherein E in Is the arterial elastic modulus, h is the arterial thickness, r is the arterial radius, ρ is the blood density;
as the mean blood pressure MBP increases, the elastic modulus of the artery increases exponentially, and the elastic modulus of the artery can be expressed as:
E in ＝E 0 e α*MBP (7)
wherein E is 0 The blood pressure value is Young modulus of a blood vessel wall when 0 is obtained, and alpha is a specific parameter related to a human blood vessel;
this is obtained by equations (1), (6) and (7):
and the mean blood pressure MBP can be expressed as:
then it is possible to obtain:
the relationship between the systolic pressure, the diastolic pressure and the time delay can be obtained according to the equations (5) and (10):
wherein H a 、H b 、H c 、J a 、J b 、J c Are coefficients associated with the individuals, respectively; the pulse transmission time can be detected for a large number of individuals, the obtained value is compared with the blood pressure result measured by a standard sphygmomanometer, and then the correlation coefficient is obtained through data fitting.
Further, the coefficient H is determined a 、H b 、H c 、J a 、J b 、J c The specific process comprises the following steps: collecting a plurality of adult blood pressure data without hypertensive heart disease history, and taking a commercial wrist-band sphygmomanometer as a reference standard; the monitoring device of claim 1 and a commercial wrist-band sphygmomanometer are used for synchronously acquiring blood pressure and pulse information of a subject, pulse waveforms acquired by the monitoring device at least comprise 10 pulse periods, an average value of pulse transmission time is obtained to serve as a final PTT value, a nonlinear least square method is adopted to fit a PTT-BP curve, reference values are obtained through fitting, and values of all obtained coefficients are respectively:
H a ＝370.12、H b ＝17.73、H c ＝358.46、J a ＝192.30、J b ＝9.13、J c ＝196.99。
compared with the prior art, the invention has the beneficial effects that:
according to the human body multi-parameter monitoring device based on the self-mixing interference and the micro-nano optical fibers, the pulse vibration signals are captured by using the sensing diaphragm embedded with the micro-nano optical fibers, the pulse vibration signals are captured by utilizing the deformation of the waveguide structure caused by the bending deformation of the micro-nano optical fibers, and the human body multi-parameter monitoring device has high sensitivity; the pulse information is monitored by the self-mixing interference technology of the laser, the blood pressure is further calculated by the pulse information, the accurate pulse information and blood pressure measurement results can be obtained, and convenience is brought to accurate monitoring of the pulse and the blood pressure of a human body.
The device of the invention comprehensively considers the influence of physiological factors of blood density, artery radius, artery thickness, artery blood volume and artery elasticity in the calculation of blood pressure, obtains a nonlinear relation model between systolic pressure, diastolic pressure and pulse transmission time respectively, and can accurately measure the systolic pressure and the diastolic pressure through the pulse transmission time.
The device has the advantages of high accuracy, simple structure, good comfort, low cost and convenient measurement, and is a pulse and blood pressure monitoring device with better application prospect.
Drawings
FIG. 1 is a schematic structural diagram of a human blood pressure monitoring device based on self-mixing interference and micro-nano optical fibers in an embodiment of the invention;
FIG. 2 is a schematic structural diagram of a sensing diaphragm and a photo of the sensing diaphragm after light with a wavelength of 650nm is introduced;
fig. 3 is an electric field intensity distribution diagram corresponding to micro-nano optical fibers in different bending states in an embodiment of the present invention;
FIG. 4 is a graph of a spectrum obtained by Fourier transforming a pulse wave according to an embodiment of the present invention, wherein (a) is a graph of a pulse waveform, (b) is a graph of a partial pulse waveform, and (c) is a graph of a Fourier transformed pulse spectrum;
FIG. 5 is a graph of SBP and DBP versus PTT, and a plot of Bland-Altman for SBP and DBP, where (a) is a graph of SBP versus PTT, (b) is a graph of DBP versus PTT, (c) is a plot of Bland-Altman for SBP, and (d) is a plot of Bland-Altman for DBP, according to an embodiment of the present invention;
FIG. 6 is a graph of SBP and DBP measurements taken by subjects over a day in accordance with an embodiment of the present invention;
FIG. 7 is a waveform diagram and a spectrum diagram after Fourier transform of a finger pulse according to an embodiment of the present invention.
Detailed Description
In the description of the present invention, it should be noted that the terms "first", "second" and "third" mentioned in the embodiments of the present invention are only used for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
As shown in figure 1, the invention provides a human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fibers, which comprises a sensing diaphragm, a laser, a photoelectric detector, a data acquisition card, a signal processing unit and a blood pressure calculating unit; the type of the laser is S1FC1550PM and THORLABS, light with the output wavelength of 1550nm is output, the output power is 2mW, the type of the data acquisition card is USB-4431, NI;
the sensing diaphragm comprises a micro-nano optical fiber and a flexible diaphragm, the micro-nano optical fiber is embedded in the flexible diaphragm, the sensing diaphragm is used for acquiring pulse information, and the flexible diaphragm is deformed due to pulse vibration to change the refraction slope of the micro-nano optical fiber;
the laser is connected with one end of the micro-nano optical fiber through the optical fiber, the other end of the micro-nano optical fiber is provided with a reflection end, the laser can emit an output optical signal with a certain wavelength under the action of driving current, the output optical signal passes through the pulse vibration part and is reflected by the reflection end, and an optical signal carrying pulse information returns to the inside of a laser resonant cavity to generate a self-mixing interference signal with an original optical field;
the photoelectric detector is arranged in the laser and used for converting the self-mixing interference signal into a continuous analog signal and sending the continuous analog signal to the data acquisition card;
the data acquisition card is connected with the photoelectric detector, is a USB dynamic signal acquisition card and is used for converting received analog signals into digital signals and transmitting the digital signals to the signal processing unit;
the signal processing unit is used for processing the received digital signals to obtain pulse wave information and transmitting the pulse wave information to the blood pressure calculating unit;
the blood pressure calculating unit is used for calculating a human blood pressure value according to the pulse wave information.
As shown in fig. 2, the manufacturing process of the sensing diaphragm is as follows: drawing a standard single-mode fiber (the diameter of a cladding is 125um, the diameter of a fiber core is 9 um) into a double-conical micro-nano fiber by a tapering machine by adopting a melting drawing method, and obtaining the micro-nano fiber with the lengths of conical regions at two ends of 15mm, the length of a waist region of 12mm and the diameter of the waist region of 1.8 um; the preparation method of the flexible membrane comprises the steps of selecting Dow Corning silicon rubber, mixing Polydimethylsiloxane (PDMS) and a curing agent according to the mass ratio of 10 to 1, degassing the PDMS in a vacuum pumping mode, paving a proper amount of degassed polydimethylsiloxane mixed solution on a glass sheet with the length of 7.5cm and the width of 2.2cm, embedding a drawn micro-nano optical fiber into the polydimethylsiloxane mixed solution, curing the micro-nano optical fiber at 80 ℃ for 20 minutes to form a thin film, and taking the thin film off the glass sheet to obtain the sensing membrane with the length of 7.5cm, the width of 2.2cm and the thickness of 0.3 mm.
As shown in FIG. 3, the electric field intensity distribution of the micro-nano optical fiber with the waist diameter of 1.8um at the bending part under the wavelength of 1550nm has the bending radii of 60 μm, 30 μm and 10 μm respectively. It is obvious that when the bending radius of the optical fiber is smaller and smaller, the well-confined guided mode leakage is more obvious and gradually converted into an asymmetric radiation mode, and the energy loss of the laser is larger.
The refractive index (RI = 1.40) of the PDMS flexible membrane of the sensing membrane is lower than the refractive index (RI = 1.46) of the micro-nano optical fiber, the flexible membrane encapsulates and protects the micro-nano optical fiber, the micro-nano optical fiber can be effectively wrapped, an evanescent field is isolated, and high mechanical flexibility and low optical loss of the micro-nano optical fiber are guaranteed.
Compared with the sensing diaphragm with the sandwich structure, the sensing diaphragm prepared by the method can avoid the influence on the detection result caused by bubbles generated in the diaphragm. And the sensing membrane has the advantages of good biocompatibility, corrosion resistance, capability of being tightly attached to the surface of the skin to eliminate air gaps and high sensitivity.
As shown in fig. 4, the signal processing unit processes the received digital signal to obtain the pulse wave information, and the specific implementation process is as follows: and processing the digital signal by LabVIEW software to obtain a pulse oscillogram, and converting the pulse oscillogram into a pulse spectrogram by Fourier transform to obtain pulse waveform information and frequency information.
The blood pressure calculating unit calculates the human blood pressure value according to the pulse wave information, and the specific realization process is as follows:
determining the time span from the main wave peak value to the heavy vibration wave peak value according to the pulse spectrogram, and expressing the time span as pulse transmission time PTT; the relationship between the pulse transmission time PTT and the pulse wave velocity PWV is:
wherein, L represents the length of a blood vessel through which the pulse wave passes;
according to the Brawell-hill equation, the pulse wave velocity PWV can be represented by the blood density ρ and the arterial blood volume v, specifically:
where V is the intra-arterial blood volume, dV is the change in intra-arterial blood volume, dP is the blood pressure difference between the systolic pressure SBP and the diastolic pressure DBP, in mmHg, and dP can be expressed as:
dP＝SBP-DBP (3)
the pulse wave velocity PWV can therefore be expressed as:
from equation (1) and equation (4) we can obtain:
on the other hand, the pulse wave velocity PWV can be expressed by the Moens-korteweg equation:
wherein E in Is the arterial elastic modulus, h is the arterial thickness, r is the arterial radius, ρ is the blood density;
as the mean blood pressure MBP increases, the elastic modulus of the artery increases exponentially, and the elastic modulus of the artery can be expressed as:
E in ＝E 0 e α*MBP (7)
wherein E is 0 The blood pressure value is Young modulus of a blood vessel wall when 0 is obtained, and alpha is a specific parameter related to a human blood vessel;
this is obtained by equations (1), (6) and (7):
and the mean blood pressure MBP can be expressed as:
then it can be obtained:
the relationship between the systolic pressure, the diastolic pressure and the time delay can be obtained according to the equations (5) and (10):
wherein H a 、H b 、H c 、J a 、J b 、J c Respectively, coefficients associated with the individuals; the pulse transmission time of a large number of individuals can be detected, the obtained value is compared with the blood pressure result measured by a standard sphygmomanometer, and then the correlation coefficient is obtained through data fitting.
Determining the coefficient H a 、H b 、H c 、J a 、J b 、J c The specific process comprises the following steps: collecting a plurality of adult blood pressure data without hypertensive heart disease history, and taking a commercial wrist-band sphygmomanometer as a reference standard; the monitoring device of claim 1 and a commercial wrist-band sphygmomanometer are used for synchronously acquiring blood pressure and pulse information of a subject, pulse waveforms acquired by the monitoring device at least comprise 10 pulse periods, an average value of pulse transmission time is obtained to serve as a final PTT value, a nonlinear least square method is adopted to fit a PTT-BP curve, reference values are obtained through fitting, and values of all obtained coefficients are respectively:
H a ＝370.12、H b ＝17.73、H c ＝358.46、J a ＝192.30、J b ＝9.13、J c ＝196.99。
the calculation models for constructing the systolic pressure and the diastolic pressure are respectively as follows:
the performance evaluation of the blood pressure measuring device of the present invention:
as shown in table 1, 18 subjects were selected to perform blood pressure measurement, and for each subject, blood pressure was measured using the apparatus of the present embodiment while accuracy was verified using an ohron sphygmomanometer, and table 1 includes reference values and deviation values of pulse wave time delay PTT(s), systolic blood pressure SBP (mmHg), diastolic blood pressure DBP (mmHg), pulse wave frequency HR (bpm), and the ohron sphygmomanometer.
The Mean Absolute error (Mean) and Standard Deviation (SD) are used as performance prediction indexes of the device.
TABLE 1
The average absolute error and the average standard deviation are calculated as follows: mean is a measure of the Mean SBP ＝-0.222、Mean DBP ＝-1.056、SD SBP ＝2.636、SD DBP And the result is in an acceptable range, so that the accuracy requirement of people on the blood pressure measuring device can be met, and the reliability of the device is proved.
For better verification of the system detection results, as shown in fig. 5 (a) and fig. 5 (b), the graphs of SBP and DBP versus PTT are shown, respectively, and it can be seen that the measured values of 18 subjects have high correlation with the relationship curves; as shown in fig. 5 (c) and 5 (d), the blood pressure of all the testers was analyzed by the Bland-Altman concordance analysis method, wherein the 95% confidence interval of SBP was-5.457-4.822mmhg and the 95% confidence interval of dbp was-5.651-3.105 mmHg; it can be seen that the measurement results of both SBP and DBP are within the 95% confidence test range, which also indicates that the SBP and DBP have strong consistency, and further verifies the reliability of the device of the invention.
As shown in fig. 6, in order to verify the accuracy of the device of the present invention in monitoring blood pressure fluctuation for a plurality of times in a day, the device of the present invention is used for measuring the blood pressure of the subject for 2 minutes every two hours in a day, and the ohm dragon blood pressure meter is used for measuring the blood pressure of the subject as a reference value, and the measurement is performed for 8 times in total; the blood pressure change trend of the subject is close to the reference value trend, so that the device can accurately monitor the blood pressure for multiple times within a period of time, and a foundation is laid for further research and development of the wearable portable real-time blood pressure monitoring device.
To further verify the performance of the device of the present invention in measuring blood pressure, the blood pressure was measured for ten consecutive days on the subject. The measurement time is 8 o 'clock to 9 o' clock in the evening, and the blood pressure of the subject is measured by using an ohm dragon blood pressure meter as a reference value. As shown in Table 2, the measurement results of a subject for ten days and the measurement error from the reference blood pressure are shown. It can be seen from table 2 that the measurement errors are small and within acceptable ranges.
TABLE 2
As shown in fig. 7, when the sensor is placed on the index finger tip, the fingertip pulse can be detected, and it can be seen that the heavy vibration wave in the obtained waveform result is not obvious enough, so that the micro-nano optical fiber with smaller diameter and the thinner PDMS membrane are needed to improve the sensitivity of the sensor, so as to realize the high-quality signal acquisition of the finger pulse.
Although the present disclosure has been described with reference to the above embodiments, the scope of the present disclosure is not limited thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present disclosure, and these changes and modifications are intended to be within the scope of the present disclosure.
Claims (10)
1. The human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fibers is characterized by comprising a sensing diaphragm, a laser, a photoelectric detector, a data acquisition card, a signal processing unit and a blood pressure calculating unit;
the sensing diaphragm comprises a micro-nano optical fiber and a flexible diaphragm, the micro-nano optical fiber is embedded in the flexible diaphragm, the sensing diaphragm is used for acquiring pulse information, and the flexible diaphragm is deformed due to pulse vibration to change the refraction slope of the micro-nano optical fiber;
the laser is connected with one end of the micro-nano optical fiber through the optical fiber, the other end of the micro-nano optical fiber is provided with a reflection end, the laser can emit an output optical signal with a certain wavelength under the action of driving current, the output optical signal passes through a pulse vibration part and is reflected by the reflection end, and an optical signal carrying pulse information returns to the inside of a resonant cavity of the laser to generate a self-mixing interference signal with an original optical field;
the photoelectric detector is arranged in the laser and used for converting the self-mixing interference signal into a continuous analog signal and sending the continuous analog signal to the data acquisition card;
the data acquisition card is connected with the photoelectric detector, is a USB dynamic signal acquisition card and is used for converting received analog signals into digital signals and transmitting the digital signals to the signal processing unit;
the signal processing unit is used for processing the received digital signals to obtain pulse wave information and transmitting the pulse wave information to the blood pressure calculating unit;
the blood pressure calculating unit is used for calculating a human blood pressure value according to the pulse wave information.
2. The human body multiparameter monitoring device based on self-mixing interference and micro-nano fibers according to claim 1, wherein the micro-nano fibers are biconical micro-nano fibers, the lengths of the conical regions at the two ends of the biconical micro-nano fibers are both 15mm, the length of the waist region is 12mm, and the diameter of the waist region is 1.8 μm.
3. The human body multiparameter monitoring device based on self-mixing interference and micro-nano optical fibers as claimed in claim 2, wherein the flexible membrane is a polydimethylsiloxane membrane.
4. The human body multiparameter monitoring device based on self-mixing interference and micro-nano optical fibers according to claim 3, wherein the length of the sensing diaphragm is 7.5cm, and the width of the sensing diaphragm is 2.2cm.
5. The human body multiparameter monitoring device based on self-mixing interference and micro-nano optical fibers according to claim 4, wherein the specific implementation process of embedding the micro-nano optical fibers in the flexible membrane is as follows: spreading proper amount of degassed polydimethyl siloxane on a glass sheet with a certain size, embedding the micro-nano optical fiber into the polydimethyl siloxane, curing to form a membrane, and taking down the membrane from the glass sheet, namely embedding the micro-nano optical fiber into the flexible membrane.
6. The human body multiparameter monitoring device based on self-mixing interference and micro-nano optical fibers according to claim 5, wherein the curing treatment is performed by heating at 80 ℃ for 20 minutes.
7. The human body multiparameter monitoring device based on self-mixing interference and micro-nano fibers according to claim 6, wherein the biconical micro-nano fibers are prepared by a fusion-drawing method through a tapering machine.
8. The human body multiparameter monitoring device based on self-mixing interference and micro-nano optical fibers according to claim 1, wherein the signal processing unit is used for processing received digital signals to obtain pulse wave information, and the specific implementation process is as follows: and processing the digital signals by LabVIEW software to obtain a pulse oscillogram, and simultaneously converting the pulse oscillogram into a pulse spectrogram by Fourier transformation to obtain pulse waveform information and frequency information.
9. The human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fibers according to claim 8, wherein the blood pressure calculating unit is used for calculating a human body blood pressure value according to pulse wave information, and the specific implementation process is as follows:
determining the time span from the main wave peak value to the heavy vibration wave peak value according to the pulse spectrogram, and expressing the time span as pulse transmission time PTT; the relationship between the pulse transmission time PTT and the pulse wave velocity PWV is:
wherein, L represents the length of a blood vessel through which a pulse wave passes;
according to the Brawell-hill equation, the pulse wave velocity PWV can be represented by the blood density ρ and the arterial blood volume v, specifically:
where V is the intra-arterial blood volume, dV is the change in intra-arterial blood volume, dP is the blood pressure difference between the systolic pressure SBP and the diastolic pressure DBP, in mmHg, and dP can be expressed as:
dP＝SBP-DBP (3)
the pulse wave velocity PWV can thus be expressed as:
from equation (1) and equation (4) we can obtain:
on the other hand, the pulse wave velocity PWV can be expressed by the Moens-korteweg equation:
wherein E in Is the arterial elastic modulus, h is the arterial thickness, r is the arterial radius, ρIs the blood density;
as the mean blood pressure MBP increases, the elastic modulus of the artery increases exponentially, and the elastic modulus of the artery can be expressed as:
E in ＝E 0 e α*MBP (7)
wherein, E 0 The blood pressure value is Young modulus of a blood vessel wall when 0 is obtained, and alpha is a specific parameter related to a human blood vessel;
this is obtained by equations (1), (6) and (7):
and the mean blood pressure MBP can be expressed as:
then it can be obtained:
the relationship between the systolic pressure, the diastolic pressure and the time delay can be obtained according to the equations (5) and (10):
wherein H a 、H b 、H c 、J a 、J b 、J c Are coefficients associated with the individuals, respectively; the pulse transmission time of a large number of individuals can be detected, and the obtained value is compared with the blood pressure result measured by a standard sphygmomanometerAnd (5) comparing, and then obtaining a correlation coefficient through data fitting.
10. The human body multiparameter monitoring device based on self-mixing interference and micro-nano optical fiber according to claim 9, wherein the coefficient H is determined a 、H b 、H c 、J a 、J b 、J c The specific process comprises the following steps: collecting a plurality of adult blood pressure data without hypertensive heart history, and taking a commercial wrist-band sphygmomanometer as a reference standard; the monitoring device of claim 5 and a commercial wrist-band sphygmomanometer are used for synchronously acquiring blood pressure and pulse information of a subject, the pulse waveform acquired by the monitoring device at least comprises 10 pulse periods, the average value of pulse transmission time is obtained and used as a final PTT value, a nonlinear least square method is adopted to fit a PTT-BP curve, a reference value is obtained by fitting, and the obtained values of all coefficients are respectively:
H a ＝370.12、H b ＝17.73、H c ＝358.46、J a ＝192.30、J b ＝9.13、J c ＝196.99。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210873107.1A CN115153469B (en) | 2022-07-22 | 2022-07-22 | Human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210873107.1A CN115153469B (en) | 2022-07-22 | 2022-07-22 | Human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115153469A true CN115153469A (en) | 2022-10-11 |
| CN115153469B CN115153469B (en) | 2024-05-24 |
Family
ID=83497307
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210873107.1A Active CN115153469B (en) | 2022-07-22 | 2022-07-22 | Human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115153469B (en) |
Citations (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4976268A (en) * | 1988-06-24 | 1990-12-11 | Colin Electronics Co., Ltd. | Pressure-pulse-wave detecting apparatus |
| US20060264771A1 (en) * | 2005-05-20 | 2006-11-23 | Dailycare Biomedical Inc. | Apparatus for evaluating cardiovascular functions |
| US20070276265A1 (en) * | 2006-05-24 | 2007-11-29 | John Borgos | Optical vital sign detection method and measurement device |
| US20160038030A1 (en) * | 2013-03-15 | 2016-02-11 | Avinger, Inc. | Optical pressure sensor assembly |
| CN106124029A (en) * | 2016-06-17 | 2016-11-16 | 中国人民解放军国防科学技术大学 | Fiber-optic hydrophone system based on the full optical phase modulator of micro-nano fiber |
| CN106840226A (en) * | 2017-03-29 | 2017-06-13 | 南京大学 | Flexible wearable health sensor and its preparation and measurement method based on micro optical fiber structure |
| CN107817009A (en) * | 2017-09-30 | 2018-03-20 | 中国科学院长春光学精密机械与物理研究所 | A kind of laser detects monitoring device from mixing |
| US20180116512A1 (en) * | 2014-07-17 | 2018-05-03 | I Sonic Medical Corporation, S.A.S. | Measurement of ocular parameters using vibrations induced in the eye |
| WO2018113442A1 (en) * | 2016-12-21 | 2018-06-28 | 天津普仁万合信息技术有限公司 | Continuous ambulatory blood pressure monitoring device and method based on pulse wave transit |
| CN108760024A (en) * | 2018-07-02 | 2018-11-06 | 东北石油大学 | A kind of two vibration parameters detection methods and device based on oneself mixing of laser |
| CN108775954A (en) * | 2018-06-06 | 2018-11-09 | 岭南师范学院 | A kind of adjustable dual wavelength LD of resolution ratio is from mixing vibration measuring instrument and its measurement method |
| US20190125201A1 (en) * | 2017-10-31 | 2019-05-02 | Onesoftdigm Co., Ltd | Method and apparatus for measuring blood pressure using optical sensor |
| CN110226924A (en) * | 2019-05-21 | 2019-09-13 | 华中科技大学 | A kind of wearable blood pressure monitoring device and method |
| US20200275888A1 (en) * | 2017-09-26 | 2020-09-03 | Toyobo Co., Ltd. | Biological information presentation system and training method |
| CN111751330A (en) * | 2020-06-28 | 2020-10-09 | 电子科技大学 | Plasmon gas sensor based on D-shaped optical fiber graphene heterojunction |
| US20200330029A1 (en) * | 2017-12-14 | 2020-10-22 | Essenlix Corporation | Devices, systems, and methods for monitoring hair |
| CN112190245A (en) * | 2020-11-06 | 2021-01-08 | 深圳市汇顶科技股份有限公司 | Blood pressure measuring device and blood pressure measuring method |
| US20210010797A1 (en) * | 2019-07-09 | 2021-01-14 | Apple Inc. | Self-Mixing Interferometry Sensors Used to Sense Vibration of a Structural or Housing Component Defining an Exterior Surface of a Device |
| CN113100731A (en) * | 2021-05-21 | 2021-07-13 | 苏州安莱光电科技有限公司 | Blood pressure monitoring device and method |
| CN113483671A (en) * | 2021-05-11 | 2021-10-08 | 岭南师范学院 | Real-time orthogonal laser self-mixing interference displacement measuring instrument and displacement reconstruction method |
-
2022
- 2022-07-22 CN CN202210873107.1A patent/CN115153469B/en active Active
Patent Citations (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4976268A (en) * | 1988-06-24 | 1990-12-11 | Colin Electronics Co., Ltd. | Pressure-pulse-wave detecting apparatus |
| US20060264771A1 (en) * | 2005-05-20 | 2006-11-23 | Dailycare Biomedical Inc. | Apparatus for evaluating cardiovascular functions |
| US20070276265A1 (en) * | 2006-05-24 | 2007-11-29 | John Borgos | Optical vital sign detection method and measurement device |
| US20160038030A1 (en) * | 2013-03-15 | 2016-02-11 | Avinger, Inc. | Optical pressure sensor assembly |
| US20180116512A1 (en) * | 2014-07-17 | 2018-05-03 | I Sonic Medical Corporation, S.A.S. | Measurement of ocular parameters using vibrations induced in the eye |
| CN106124029A (en) * | 2016-06-17 | 2016-11-16 | 中国人民解放军国防科学技术大学 | Fiber-optic hydrophone system based on the full optical phase modulator of micro-nano fiber |
| WO2018113442A1 (en) * | 2016-12-21 | 2018-06-28 | 天津普仁万合信息技术有限公司 | Continuous ambulatory blood pressure monitoring device and method based on pulse wave transit |
| CN106840226A (en) * | 2017-03-29 | 2017-06-13 | 南京大学 | Flexible wearable health sensor and its preparation and measurement method based on micro optical fiber structure |
| US20200275888A1 (en) * | 2017-09-26 | 2020-09-03 | Toyobo Co., Ltd. | Biological information presentation system and training method |
| CN107817009A (en) * | 2017-09-30 | 2018-03-20 | 中国科学院长春光学精密机械与物理研究所 | A kind of laser detects monitoring device from mixing |
| US20190125201A1 (en) * | 2017-10-31 | 2019-05-02 | Onesoftdigm Co., Ltd | Method and apparatus for measuring blood pressure using optical sensor |
| US20200330029A1 (en) * | 2017-12-14 | 2020-10-22 | Essenlix Corporation | Devices, systems, and methods for monitoring hair |
| CN108775954A (en) * | 2018-06-06 | 2018-11-09 | 岭南师范学院 | A kind of adjustable dual wavelength LD of resolution ratio is from mixing vibration measuring instrument and its measurement method |
| CN108760024A (en) * | 2018-07-02 | 2018-11-06 | 东北石油大学 | A kind of two vibration parameters detection methods and device based on oneself mixing of laser |
| CN110226924A (en) * | 2019-05-21 | 2019-09-13 | 华中科技大学 | A kind of wearable blood pressure monitoring device and method |
| US20210010797A1 (en) * | 2019-07-09 | 2021-01-14 | Apple Inc. | Self-Mixing Interferometry Sensors Used to Sense Vibration of a Structural or Housing Component Defining an Exterior Surface of a Device |
| CN111751330A (en) * | 2020-06-28 | 2020-10-09 | 电子科技大学 | Plasmon gas sensor based on D-shaped optical fiber graphene heterojunction |
| CN112190245A (en) * | 2020-11-06 | 2021-01-08 | 深圳市汇顶科技股份有限公司 | Blood pressure measuring device and blood pressure measuring method |
| CN113483671A (en) * | 2021-05-11 | 2021-10-08 | 岭南师范学院 | Real-time orthogonal laser self-mixing interference displacement measuring instrument and displacement reconstruction method |
| CN113100731A (en) * | 2021-05-21 | 2021-07-13 | 苏州安莱光电科技有限公司 | Blood pressure monitoring device and method |
Non-Patent Citations (1)
| Title |
|---|
| 姜春雷;周旭明;: "基于激光自混合干涉技术和小波变换的齿轮箱故障诊断", 光学技术, no. 01, 15 January 2017 (2017-01-15) * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115153469B (en) | 2024-05-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100905571B1 (en) | Apparatus for measuring living body information | |
| CN103892818B (en) | A kind of non-invasive central arterial blood pressure measuring method and equipment | |
| Li et al. | Wearable alignment-free microfiber-based sensor chip for precise vital signs monitoring and cardiovascular assessment | |
| CN102772200B (en) | Pulse-taking signal sensor probe and optical fiber pulse-taking information acquisition system | |
| KR20090121874A (en) | Apparatus and method for sensing radial arterial pulses for noninvasive and continuous measurement of blood pressure | |
| US20110152699A1 (en) | Blood pressure measuring apparatus and method for measuring blood vessel elasticity | |
| Li et al. | Continuous and accurate blood pressure monitoring based on wearable optical fiber wristband | |
| CN113348427A (en) | Soft capacitance type pressure sensor | |
| CN103829936A (en) | Optical fiber craniocerebral pressure monitor | |
| Leitão et al. | Optical fiber sensors for central arterial pressure monitoring | |
| CN102579017A (en) | Non-invasive blood flow kinetic parameter analysis meter | |
| Liang et al. | Wearable and multifunctional self-mixing microfiber sensor for human health monitoring | |
| Pang et al. | Singlemode-multimode-singlemode optical fiber sensor for accurate blood pressure monitoring | |
| TW200520728A (en) | Auto diagnosing method and device thereof for autonomic nervous | |
| CN103610454A (en) | Blood pressure measurement method and system | |
| CN115153469B (en) | Human body multi-parameter monitoring device based on self-mixing interference and micro-nano optical fiber | |
| JP2006519045A (en) | Blood pressure microsensor and measuring instrument using the blood pressure microsensor | |
| Taoping et al. | Design of pulse and respiration monitoring system based on fiber optic sensing and VMD-FPR processing algorithm | |
| CN116392091A (en) | Continuous arterial blood pressure waveform detection system and device based on single-channel finger tip PPG | |
| CN110786843A (en) | Noninvasive optical measurement method for intracranial pressure | |
| CN113317765B (en) | Optical tattoo sensing film, preparation method thereof and all-fiber digital pulse instrument | |
| Guo et al. | Combining local PWV and quantified arterial changes for calibration-free cuffless blood pressure estimation: A clinical validation | |
| CN115316966A (en) | Blood pressure detection device and method based on-chip optical microcavity | |
| KR101327229B1 (en) | Pulse wave velocity measurement system and method for u-healthcare using dual-sensor and elastic band | |
| Ma et al. | Pulse wave measuring via fingertip-like sensor to analyze and identify pulse-rate status |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant |