CN115192075A

CN115192075A - Bone density measuring method with self-contained SOS correction and suitable for different physique detection

Info

Publication number: CN115192075A
Application number: CN202210734477.7A
Authority: CN
Inventors: 茅洁芳; 史哲成
Original assignee: Hunan Shengbeite Medical Technology Co ltd
Current assignee: Hunan Shengbeite Medical Technology Co ltd
Priority date: 2022-06-27
Filing date: 2022-06-27
Publication date: 2022-10-18

Abstract

The invention discloses a bone mineral density measuring method with self SOS correction and suitable for different physique detection, which adopts an ultrasonic bone mineral density measuring system comprising an upper computer and a lower computer, wherein the lower computer comprises a bone mineral density measuring instrument, the bone mineral density measuring instrument comprises a shell, an adjustable excitation module, an adjustable receiving module, a control processing module, an ultrasonic probe and a temperature sensor, and the method comprises the following steps: s1, correcting coefficients calculated by the SOS; s2, setting an excitation voltage and a receiving gain; and S3, correcting and acquiring the SOS value. On one hand, the detected target is not influenced by the fat and thin physique through the selection of the excitation voltage and the gain of the receiving circuit, the signal consistency is better, and the requirement of a subsequent signal processing circuit is reduced; on the other hand, the SOS value is compensated and corrected through the acquired environmental temperature and body temperature information, and the accuracy of the SOS value is improved.

Description

Bone density measuring method with self-contained SOS correction and suitable for different physique detection

Technical Field

The invention belongs to the technical field of medical treatment, and particularly relates to a bone mineral density measuring method with self SOS correction and suitable for different physique detection.

Background

The bone density is measured by an ultrasonic bone density measuring instrument, and the ultrasonic bone density measuring instrument has the characteristics of no radiation, convenient operation and low price, is used for detecting parameters of human body bone density, bone strength and the like, and has good reference and guidance values for preventing and treating calcium deficiency of fetuses and infants and fracture/bone loss of pregnant women and lactating mothers and osteoporotic old people.

Ultrasonic bone densitometers are mainly classified into two types according to the difference of measurement positions: the calcaneus ultrasonic bone densitometer and the multi-part acoustic bone densitometer, wherein the multi-part acoustic bone densitometer comprises a radius, a phalanx cavity bone, a hip bone and the like, and the multi-part acoustic bone densitometer has the advantages of simplicity and convenience in operation, high scanning speed, convenience in large-scale data screening, capability of selecting the radius for detection, no cross infection easily caused by heel measurement, capability of causing beriberi, tinea pedis and the like, suitability for broad groups such as infants, children, adults and the old, and good technical advantages and market prospects.

At present, the bone mineral density ultrasonic bone mineral density measurement is bone ultrasonic sound velocity value (SOS). The calcaneus densitometer mainly measures the time of passing through both sides of the fixed length of the heel bone, thereby obtaining the SOS. The basic principle of a multi-site ultrasonic bone densitometer (such as a radius densitometer) is that an ultrasonic probe emits ultrasonic waves from one end of the skin outside a bone, receives the ultrasonic waves attenuated by the bone and soft tissues and reaching the other end of the probe, obtains the time of propagation in the bone, and further measures the bone ultrasonic sound velocity value (SOS) closely related to the bone density.

However, in actual operation, there are the following technical problems:

1. the system circuit of the bone densitometer is a high-voltage circuit of a transmitting end or a digital processing circuit of a receiving end, the amplitude, pulse width and frequency of the generated excitation high voltage are fixed, and all gains of the receiving end are also fixed when the device works after debugging, namely, the formed excitation voltage and detection sensitivity are fixed, so that the signal response difference to different crowds is large, and the consistency is low;

2. the bone densitometer has a limited detection depth and cannot measure particularly obese people;

3. the method is easily influenced by temperature, and the SOS result has certain deviation;

4. the whole size of equipment is great, and outdoor removal is used inconveniently.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a brand-new bone density measuring method with self SOS correction and suitable for different physique detection.

In order to achieve the purpose, the invention adopts the technical scheme that: the utility model provides a from taking SOS to revise and be applicable to the bone density measurement method that different physique detected, it has adopted supersound bone density measurement system, supersound bone density measurement system includes host computer, next machine, and wherein the next machine includes bone density measuring apparatu, and bone density measuring apparatu includes casing, adjustable excitation module, adjustable receiving module, control processing module and ultrasonic probe and temperature sensor, and includes following step:

s1, coefficient correction of SOS calculation

Smearing a couplant on the end part of a bone density measuring instrument where an ultrasonic probe is located, then contacting a body membrane to obtain a corresponding body membrane sound velocity, simultaneously obtaining the ambient temperature by a temperature sensor to be used as the body membrane temperature, automatically reading a standard value of the body membrane velocity at the corresponding temperature by an upper computer, and correcting the coefficient calculated by the SOS;

s2, setting of excitation voltage and receiving gain

The constitution and physical sign parameters of the detected target are input into the upper computer, wherein the BMI value of the detected target is taken as a reference, and the V excitation value of the excitation voltage is selected as follows:

a in the logarithmic function in the formula (1) is a number smaller than 1, and K1 is a range function of amplitude increase and is the difference value between the highest excitation voltage and the standard voltage; k2 is a range function of amplitude reduction and is the difference value of the lowest excitation voltage and the standard voltage;

g of receiving gain _{Gain of} The values were chosen as follows:

b in the logarithmic function in the formula (2) is a number smaller than 1, L1 is a range function for increasing the adjustable gain and is the difference value between the highest adjustable gain and the standard gain; l2 is a range function of amplitude reduction and is the difference between the lowest gain and the standard;

s3, correcting and obtaining SOS value

Coating coupling agent on the surface of the object to be detected, and coating selected V _Excitation And G _{Gain of} Under the working mode, the end part of a bone density measuring instrument where the ultrasonic probe is located is contacted with an object to be detected, the upper computer can display the ultrasonic sound velocity value of the bone corresponding to the detected position in real time, simultaneously detect and obtain the body temperature of the human body according to the temperature sensor, select correction factors of different human body temperatures on the sound velocity of the bone, and then correct the measured sound velocity to obtain an SOS value and a bone density value.

Preferably, in S2, a in formula (1) is 0 to 0.6; b in the formula (2) is 0 to 0.6.

In this case, the general obese people need to have high ultrasonic intensity because the path traversed by the sound wave is long, so the excitation voltage is high. In addition, since the ultrasonic signal finally reaching the receiving probe is weak, the adjustable gain is also large. While the leptin correspondingly attenuates the excitation voltage and the adjustable gain. Therefore, the consistency of signals obtained by detecting the fat and thin human bodies is good, and subsequent signal processing, analysis and comparison are facilitated.

Specifically, when the system excitation voltage is adjusted, the body obesity degree of the detected object is determined according to the BMI value of the detected object input into the system, and the specific excitation voltage is set according to the formula (1).

When the BMI value of the detection object is 18-24 intervals, namely the detection object has a normal body type, the excitation voltage of the system is the default standard voltage. (the standard voltage is generally about 100-200V);

when the BMI value of the detected object is between 24 and 40, namely the detected object is fat, the excitation voltage of the system starts to increase the excitation amplitude on the basis of the standard voltage.

In the formula, a in the logarithmic function is a number smaller than 1 and is generally set to 0 to 0.6. In the formula, K1 is a range function of amplitude increase and is the difference value of the highest excitation voltage and a standard voltage; when the BMI value of the detected object is more than 40, namely the detected object is extremely fat, the excitation voltage of the system modulates the highest excitation voltage (> 400V). When the BMI value of the detection object is 10-18 intervals, namely the detection object is thin, the excitation voltage of the system starts to reduce the excitation amplitude at the standard excitation voltage. In the formula, K2 is a range function of amplitude reduction and is the difference value of the lowest excitation voltage and the standard voltage; when the BMI value of the detected object is less than 11, namely the detected object is extremely thin, the excitation voltage of the system is modulated to the lowest excitation voltage (< 50V).

Meanwhile, when the system receives the adjustable gain adjustment, the body obesity degree of the system is determined according to the BMI value of the detected object input into the system, and the specific gain setting refers to the formula (2).

When the BMI value of the detection object is 18-24 intervals, namely the detection object is normal in body type, the adjustable gain of the system is the default gain. (the standard adjustable gain setting parameter is generally about 20 dB); when the BMI value of the detected object is between 24 and 40, namely the detected object is fat, the adjustable gain of the system starts to increase on the basis of the standard gain. In the formula, b in the logarithmic function is a number smaller than 1 and is generally set to 0 to 0.6. Wherein L1 is a range function of the increase of the adjustable gain and is the difference value of the highest adjustable gain and the standard gain; when the BMI value of the subject is greater than 40, i.e., the subject is extremely obese, the adjustable gain of the system will be set to the maximum gain (> 40 dB). When the BMI value of the detected object is 10-18 intervals, namely the detected object is thin, the adjustable gain of the system starts to reduce the gain on the standard. Wherein L2 is a range function of amplitude reduction and is a difference value of the lowest gain and a standard; when the BMI of the subject is less than 11, i.e., the subject is extremely thin, the adjustable gain of the system is modulated to a minimum value (< 5 dB).

And the corresponding adjusting result can be displayed on the upper computer software. Of course, the operator can also manually adjust the related excitation voltage and adjustable gain parameter according to experience and test results to obtain better measurement effect.

According to a specific implementation and preferred aspect of the present invention, in S3, when the temperature sensor detects that the temperature of the target changes from t0 to t, and corresponding to the bone at the depth z, the time shift of the sound wave before and after the temperature change changes is as follows:

θ (ξ) = θ 0+ δ θ (δ 0) in expression (3) is the temperature at the depth ξ; c (xi, theta (xi)) represents the speed of sound at depth xi and temperature theta (xi); α (ξ) represents the coefficient of thermal expansion at ξ; and the calculation formula of the sound velocity at the measured bone is changed from the original one

In the temperature compensation of sound velocity correction, the correction is:

wherein L is the distance of the ultrasonic wave propagating in the bone, and DeltaT is the time of the originally measured sound wave propagating in the bone. Therefore, correction compensation can be carried out according to the environment temperature and the real-time temperature of the probe so as to ensure that the sound velocity of the bone at the measured position is accurately obtained, and therefore the bone density is accurately obtained.

According to a specific implementation and preferred aspect of the present invention, the ultrasonic bone mineral density measuring system comprises an upper computer and a lower computer, wherein the lower computer comprises a bone mineral density measuring instrument, the bone mineral density measuring instrument comprises a housing, an adjustable excitation module, an adjustable receiving module, a control processing module and an ultrasonic probe, wherein the ultrasonic probe comprises one or more groups of ultrasonic transducers, two of the ultrasonic transducers in each group are provided, one of the ultrasonic transducers is communicated with the adjustable excitation module, and the other ultrasonic transducer is communicated with the adjustable receiving module; each group of two ultrasonic transducers are oppositely spaced and arranged in an intersecting manner in the extending direction;

the adjustable excitation module adopts a series resonance circuit, and the amplitude of the formed excitation pulse is in direct proportion to the excitation voltage of the ultrasonic transducer;

the adjustable receiving module adopts a differential amplifying circuit to realize gain adjustment change of 0-60 dB;

the control processing module is in information interaction with an upper computer, the upper computer comprises a BMI index input module of human physiological parameters, the control processing module is used for receiving information input by the BMI index input module and processing the information to form an instruction signal for controlling the triggering time and the triggering period of the pulse, the adjustable excitation module is in information interaction with the control processing module, and the amplitude of the excitation pulse is changed synchronously with the instruction signal.

Preferably, the housing is a block with a cross section being a direction or a circle, the ultrasonic probe is located at one end of the housing, the control processing module is close to the other end of the housing, and the adjustable excitation module and the adjustable receiving module are spaced side by side and located between the ultrasonic probe and the control processing module. Compact structure layout, small volume and convenient carrying.

Preferably, the working frequency of the ultrasonic probe is 1 MHz-3 MHz.

According to a specific implementation and preferred aspect of the invention, the end face of the housing is a plane, and each set of two ultrasonic transducers forms an inclination angle of 15-35 ° with the end face. Therefore, the bone ultrasonic sound velocity value (SOS) can be accurately obtained, and a plurality of groups can be distributed at the same time, so that even the obese people can accurately obtain the bone ultrasonic sound velocity value.

Preferably, a coating shielding layer is formed on the periphery of the end part of the ultrasonic probe where the ultrasonic transducer is located, the coating shielding layer abuts against the inner wall of the end part of the shell and forms a noise and electromagnetic interference prevention area, and one or more groups of ultrasonic transducers are located in the coating shielding layer.

That is, the ultrasonic probe in the portable bone densitometer described above is generally composed of 1 to 2 sets of ultrasonic transducers at an angle to each other. One of the ultrasonic probes in each group is an ultrasonic transmitting probe which is connected with an adjustable excitation module and is responsible for transmitting ultrasonic waves (an excitation probe or a transmitting probe for short) to the skeleton; the other probe is an ultrasonic receiving probe which is connected with an adjustable receiving module and receives ultrasonic waves passing through bones, soft tissues and skin (called receiving probe for short). The working frequency of the ultrasonic probe is generally 1 MHz-3 MHz. The excitation probe and the receiving probe are arranged in an inclined opposite way, and the inclined angle of the excitation probe and the receiving probe is generally about 15 degrees to 35 degrees. To prevent noise and electromagnetic interference, the probe periphery may be shielded with a copper film.

According to a specific implementation and preferred aspect of the invention, the adjustable excitation module comprises an energy storage inductor, a high-speed switching diode, an isolation capacitor, a matching resistor, an excitation controller and an excitation voltage follower, wherein the instruction can control the high-speed switching diode to be turned on or off.

That is to say, the adjustable excitation module is mainly responsible for generating a high-voltage excitation voltage, and is connected with a transmitting probe in the ultrasonic probe to drive the ultrasonic probe to transmit ultrasonic waves.

Specifically, a series resonant circuit of a low-voltage power supply is adopted, and the module mainly comprises an energy storage inductor L1, a high-speed switching diode Q, an isolation capacitor C1, a matching resistor R1, an excitation module controller G1 and an excitation voltage output device Y1.

Meanwhile, according to physiological parameters of different target human bodies, such as: according to the age, the obesity degree, the sex, the BMI index and the like, the triggering time of the control pulse T is adjusted to control the on-off of the high-speed switch diode according to the experience value obtained in clinical experiments, and the purposes of changing the amplitude and the pulse frequency of the excitation voltage of the ultrasonic probe and generating the ultrasonic excitation pulse with adjustable amplitude can be achieved. And the voltage generated by the ultrasound probe is proportional to the amplitude of the excitation pulse.

According to a specific implementation and preferred aspect of the invention, the differential amplification circuit has two variable gain amplifiers with different modulation accuracies and the two variable gain amplifiers form a cascade.

That is to say, the adjustable receiving module is mainly responsible for receiving the ultrasonic signals detected by the ultrasonic probe, and performing corresponding filtering and gain processing. In order to realize gain adjustability and meet the requirements of different target human signal detection, for example, people with obesity need extremely high gain to realize weak signal amplification so as to meet the requirements of system detection, the system is realized by adopting a Variable Gain Amplifier (VGA). The gain-adjustable differential amplifier circuit mainly adopts a mode of an adjustable gain differential amplifier circuit, and can realize a gain adjustment change of 0-60 dB. To achieve higher required gain control range and step size, it can also be implemented using a form of cascaded VGAs. The modulation accuracy of the two VGAs can also be different, thereby realizing the adjustment of different accuracy requirements and the like.

According to a specific implementation and a preferable aspect of the invention, the bone density measuring instrument further comprises a body temperature sensor and an environment temperature sensor which are respectively communicated with the control processing module, and the upper computer further comprises a bone sound speed trimming module, wherein the bone sound speed trimming module can correct the measured bone sound speed according to real-time changes of the body temperature and the environment temperature.

Preferably, the body temperature sensor is provided with a plurality of body temperature sensors and is arranged at the end part of the shell where the ultrasonic probe is arranged, and the environment temperature sensor is positioned at the end part or/and the side part far away from the ultrasonic probe.

The portable bone densitometer is also provided with a plurality of temperature detectors, wherein the temperature detectors on two sides of the ultrasonic probe are mainly responsible for detecting the body temperature of a detected human body in real time, and the temperature detector on the top end of the densitometer is mainly used for detecting the temperature of the environment. The detected related temperature data is uploaded to the upper computer software in a wireless or wired mode through the control processing module for subsequent temperature compensation.

In addition, the bone mineral density measuring instrument further comprises a power supply arranged in the shell. The power supply is also called as a mobile power supply, and can provide 5-12V voltage output to ensure the normal work of the equipment, charge and the like, and ensure the repeated use. The portable power source can be internally arranged in the portable bone densitometer and charged in a wired or NFC mode. And a rear cover can be arranged to facilitate the replacement of a power supply such as a mobile power supply, an alkaline battery, a button battery and the like.

Meanwhile, the upper computer of the portable bone densitometer is mainly responsible for receiving data transmitted by the bone densitometer and calculating the SOS of the target to be measured by using software installed in the upper computer. The upper computer also has the functions of receiving temperature data to correct SOS, inputting measured target information, intelligently adjusting system working parameters, displaying measurement and statistical results in real time, storing relevant results, issuing final measurement reports and the like. The upper computer can be a computer, an engineering machine, a notebook computer, a panel computer PAD, even a smart phone and the like.

In this example, the control processing module is mainly responsible for controlling and working the system, receiving various measurement data, performing relevant processing on the measured signal, and the like, including controlling the parameter setting and the time sequence of the excitation circuit; controlling variable gain, timing and data of the receiving circuit; processing the detection data comprises filtering, gain, envelope acquisition, detection time TOF calculation and the like; acquiring and controlling the work of the temperature detector and receiving related data; the interaction between the bone densitometer and an upper computer is realized.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:

on one hand, the detected target is not influenced by the fat and thin physique through the selection of the excitation voltage and the gain of the receiving circuit, the signal consistency is better, and the requirement of a subsequent signal processing circuit is reduced; on the other hand, the SOS value is compensated and corrected through the acquired environmental temperature and body temperature information, and the accuracy of the SOS value is improved.

Drawings

FIG. 1 is a schematic diagram of an ultrasonic bone density measurement system according to the present invention;

FIG. 2 is a schematic circuit diagram of the adjustable excitation module of FIG. 1;

FIG. 3 is a schematic diagram of the adjustable gain amplifier circuit of FIG. 1;

wherein: 1. an upper computer; 10. a BMI index input module; 11. a bone sound speed trimming module;

2. a lower computer; 20. a bone mineral density measuring instrument; 200. a housing; 201. an adjustable excitation module; 202. an adjustable receiving module; 203. a control processing module; 204. an ultrasonic probe; 205. a mobile power supply; 206. coating a shielding layer; 207. a body temperature sensor; 208. an ambient temperature sensor; a1 A2, an ultrasonic transducer; A. a group of ultrasonic transducers; q, noise and electromagnetic interference prevention zone.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying the present application are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is capable of embodiment in many different forms than those described herein and those skilled in the art will be able to make similar modifications without departing from the spirit of the application and therefore the application is not limited to the specific embodiments disclosed below.

In the description of the present application, it is to be understood that the terms "central," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and to simplify the description, but are not intended to indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and are not to be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless explicitly specified otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and encompass, for example, both fixed and removable connections or integral parts thereof; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature "under," "beneath," and "under" a second feature may be directly under or obliquely under the second feature, or may simply mean that the first feature is at a lesser elevation than the second feature. It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. As used herein, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are for purposes of illustration only and do not denote a single embodiment.

As shown in fig. 1, the bone density measurement method with self-contained SOS correction and suitable for different physical examination in this embodiment employs an ultrasonic bone density measurement system including an upper computer 1 and a lower computer 2 connected by a communication protocol.

The upper computer 1 comprises a BMI index input module 10 of human physiological parameters and a bone sound velocity trimming module 11 (receiving temperature data to correct SOS).

Meanwhile, the upper computer 1 also has SOS calculation software of the object to be measured, and also has auxiliary functions, such as: the intelligent measurement system has the functions of intelligently adjusting the working parameters of the system, displaying measurement and statistical results in real time, storing related results, issuing a final measurement report and the like.

In this example, the upper computer 1 may be a computer, an engineering machine, a notebook computer, a tablet computer PAD, or even a smart phone, and the BMI index input module 10, the bone sound velocity trimming module 11, and the SOS calculation software of the target are all located in the upper computer 1.

The lower computer 2 comprises a bone density measuring instrument 20, wherein the bone density measuring instrument 20 comprises a shell 200, an adjustable excitation module 201, an adjustable receiving module 202, a control processing module 203, an ultrasonic probe 204 and a mobile power supply 205.

Specifically, the cross section of the housing 200 is a block shape of a square or a circle.

In this example, the front projection of the housing 200 is square.

The adjustable excitation module 201 adopts a series resonant circuit, and the amplitude of the formed excitation pulse is in direct proportion to the excitation voltage of the ultrasonic transducer.

The adjustable receive module 202 employs differential amplification circuitry to achieve a gain adjustment variation of 0-60 dB.

The control processing module 203 is in information interaction with the upper computer 1, the upper computer comprises a BMI index input module of human physiological parameters, the control processing module is used for receiving information input by the BMI index input module and processing the information to form an instruction signal for controlling the triggering time and the triggering period of the pulse, the adjustable excitation module is in information interaction with the control processing module, and the amplitude of the excitation pulse is changed synchronously along with the instruction signal.

The ultrasonic probe 204 comprises two groups of ultrasonic transducers a, wherein two ultrasonic transducers a are arranged in each group, one is communicated with the adjustable excitation module 201, and the other is communicated with the adjustable receiving module 202; each set of two ultrasonic transducers a1 and a2 are oppositely spaced, and the extending directions of the two ultrasonic transducers are intersected.

Specifically, the ultrasonic probe 204 is located at the lower end of the square, the control processing module 203 is located at the upper part of the square, and the adjustable excitation module 201 and the adjustable receiving module 202 are spaced side by side and located between the ultrasonic probe 204 and the control processing module 203. Compact structure layout, small volume and convenient carrying.

The working frequency of the ultrasonic probe 204 is 1 MHz-3 MHz.

The bottom surface of the square housing 200 is a plane, and each group of two ultrasonic transducers forms an inclination angle of 20 degrees with the end surface. This corresponds to an accurately obtained ultrasonic sound velocity (SOS), and a plurality of sets can be laid out.

Meanwhile, a coating shielding layer 206 is formed on the periphery of the end of the ultrasonic transducer of the ultrasonic probe 204, the coating shielding layer 206 abuts against the inner wall of the bottom surface of the housing 200 and forms a noise and electromagnetic interference prevention region Q, and the two sets of ultrasonic transducers a are located in the coating shielding layer.

That is, the ultrasonic probe of the portable bone densitometer (i.e., the bone densitometer 20) described above generally consists of 1 to 2 sets of ultrasonic transducers at an angle to each other. One of the ultrasonic probes in each group is an ultrasonic transmitting probe which is connected with an adjustable excitation module and is responsible for transmitting ultrasonic waves (an excitation probe or a transmitting probe for short) to the skeleton; the other probe is an ultrasonic receiving probe which is connected with an adjustable receiving module and receives ultrasonic waves passing through bones, soft tissues and skin (called a receiving probe for short). The working frequency of the ultrasonic probe is generally 1 MHz-3 MHz. The excitation probe and the receiving probe are arranged in an inclined opposite mode, and the inclined angle of the excitation probe and the receiving probe is generally about 20 degrees. To prevent noise and electromagnetic interference, the probe periphery may be shielded with a copper film.

Referring to fig. 2, the adjustable excitation module 201 is a series resonant circuit of a low-voltage power supply, and the module mainly includes an energy storage inductor L1, a high-speed switching diode Q, an isolation capacitor C1, an isolation capacitor C2, two matching resistors R1, an excitation module controller G1, and an excitation voltage output device Y1, where an instruction can control the on/off of the high-speed switching diode Q.

That is, according to the physiological parameters of different target human bodies, such as: according to the age, the obesity degree, the sex, the BMI index and the like, the triggering time of the control pulse T is adjusted to control the on and off of the high-speed switch diode according to the obtained empirical value in the clinical experiment, so that the purposes of changing the amplitude and the pulse frequency of the excitation voltage of the ultrasonic probe and generating the ultrasonic excitation pulse with adjustable amplitude can be realized. And the voltage generated by the ultrasound probe is proportional to the amplitude of the excitation pulse.

As shown in fig. 3, the adjustable receiving module 202 is mainly responsible for receiving the ultrasonic signal detected by the ultrasonic probe, and performing corresponding filtering and gain processing. In order to realize gain adjustability and meet the requirements of different target human signal detection, for example, people with obesity need extremely high gain to realize weak signal amplification so as to meet the requirements of system detection, the system is realized by adopting a Variable Gain Amplifier (VGA). The gain adjusting circuit mainly adopts a mode of an adjustable gain differential amplifying circuit, and can realize gain adjustment change of 0-60 dB. To achieve higher required gain control range and step size, it can also be implemented using cascaded VGAs. The modulation accuracy of the two VGAs can also be different, thereby realizing the adjustment of different accuracy requirements and the like.

The control processing module 203 is mainly responsible for controlling and working the system, receiving various measurement data, performing relevant processing on the measured signals and the like, and comprises parameter setting and time sequence of the control excitation circuit; controlling variable gain, timing and data of the receiving circuit; processing the detection data comprises filtering, gain, envelope extraction, detection time TOF calculation and the like; acquiring and controlling the work of the temperature detector and receiving related data; the interaction between the bone densitometer and an upper computer is realized.

In addition, the bone density measuring instrument 20 further includes a body temperature sensor 207 and an ambient temperature sensor 208 respectively communicated with the control processing module 203, wherein the bone sound velocity modification module 11 can modify the measured bone sound velocity according to the real-time change of the body temperature and the ambient temperature.

The body temperature sensor 207 is provided in plurality at the end of the housing 200 where the ultrasound probe 204 is located, and the ambient temperature sensor 208 is located at the end or/and the side away from the ultrasound probe 204.

Due to the difference in the temperature of the human body, a difference between the measurement result and the standard body membrane correction result may be caused. Therefore, the system is provided with two soft-contact human body surface temperature detectors on two sides of the probe, can acquire the temperature of the human epidermis in real time and send the temperature to the upper computer software. And according to the result obtained by the human body temperature detector, correspondingly searching correction factors of different human body temperatures obtained by the large measurement database on the bone sound velocity, and then correcting the measured sound velocity so as to obtain a high-precision SOS result.

The power source 205, also called a portable power source, can provide a voltage output of 5-12V to ensure normal operation of the device, and can be charged, etc., to ensure repeated use. The portable power source can be internally arranged in the portable bone densitometer and charged in a wired or NFC mode. And a rear cover can be arranged to facilitate the replacement of a power supply such as a mobile power supply, an alkaline battery, a button battery and the like.

In summary, the implementation process of this embodiment is as follows:

s1, correction of coefficients of SOS calculation

Smearing a couplant on the end part of a bone density measuring instrument where an ultrasonic probe is located, then contacting a body membrane to obtain a corresponding body membrane sound velocity, simultaneously obtaining the ambient temperature by a temperature sensor to be used as the temperature of the body membrane (the body membrane needs to stand in the ambient environment for a period of time until the body membrane is consistent with the ambient temperature), automatically reading a standard value of the speed of the body membrane at the corresponding temperature by an upper computer, and carrying out SOS calculated coefficient correction;

s2, setting of excitation voltage and receiving gain

The physique and sign parameters of the detected target are input into the upper computer, wherein the BMI value of the detected target is taken as a reference, and the V excitation value of the excitation voltage is selected as follows:

a in the logarithmic function in the formula (1) is a number smaller than 1, and K1 is a range function of amplitude increase and is the difference value of the highest excitation voltage and the standard voltage; k2 is a range function of amplitude reduction and is the difference value of the lowest excitation voltage and the standard voltage;

g of receiving gain _{Gain of} The values were chosen as follows:

b in the logarithmic function in the formula (2) is a number smaller than 1, L1 is a range function for increasing the adjustable gain and is a difference value between the highest adjustable gain and the standard gain; l2 is a range function of amplitude reduction and is the difference between the lowest gain and the standard;

s3, correcting and obtaining SOS value

Coating coupling agent on the surface of the object to be detected, and coating selected V _Excitation And G _{Gain of} In a working mode, the end part of a bone density measuring instrument where an ultrasonic probe is located is in contact with an object to be detected, the upper computer can display the ultrasonic sound velocity value of the bone corresponding to the detected position in real time, meanwhile, the ultrasonic sound velocity value is obtained by detecting the body temperature of a human body according to the temperature sensor, correction factors of different human body temperatures on the sound velocity of the bone are selected, specifically, when the temperature sensor detects that the target temperature is changed from t0 to t, the temperature sensor corresponds to the bone at the depth z, and the time shift change of sound waves before and after the temperature change is as follows:

θ (ξ) = θ 0+ δ θ (δ 0) in the formula (3) is the temperature at the depth ξ; c (xi, theta (xi)) represents the speed of sound at depth xi and temperature theta (xi); α (ξ) represents the coefficient of thermal expansion at ξ; and the calculation formula of the sound velocity at the measured bone is changed from the original one

In the temperature compensation of the sound velocity correction, the correction is:

Further, it should be noted that: the system automatically selects excitation and gain, can also manually adjust excitation voltage and receive gain according to the experience of an operator or the test result of the system, and can directly input related system parameters on an upper computer to carry out system setting and adjustment.

In summary, the present embodiment has the following advantages:

1. the problems of fixation and insufficient adjusting capacity of a circuit module of the conventional ultrasonic bone mineral density tester can be effectively solved, and automatic selection and setting of the excitation voltage and the receiving circuit gain can be carried out according to the input physique of a target object (the excitation voltage and the receiving gain can also be adjusted manually according to the experience of an operator or the system test result), so that the same equipment can detect obese and tall people, very thin and thin people, people with different physiques such as old people and young people and the like, the signal consistency is good, and the requirement of a subsequent signal processing circuit is reduced;

2. the detection depth is designed along with two or more groups of relatively inclined probes, and even the obese people can accurately obtain the bone ultrasonic sound velocity value;

3. in order to further ensure the precision bone ultrasonic sound velocity value, a plurality of temperature detectors are inherited, so that the environment temperature can be detected, the surface temperature of a human body can also be detected, and the temperature of a measurement result can be corrected;

4. simple structure, it is small, and form portable wireless bone densimeter structure, the operation is more convenient and light.

The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered in the protection scope of the present invention.

Claims

1. A bone density measuring method with self SOS correction and suitable for different physique detection is characterized in that: it has adopted supersound bone density measurement system, supersound bone density measurement system includes host computer, next machine, and wherein the next machine includes bone density measuring apparatu, and bone density measuring apparatu includes casing, adjustable excitation module, adjustable receiving module, control processing module and ultrasonic probe and temperature sensor, and includes following step:

s1, correction of coefficients of SOS calculation

Smearing a couplant on the end part of a bone density measuring instrument where an ultrasonic probe is located, contacting a body membrane to obtain a corresponding body membrane sound velocity, simultaneously obtaining the ambient temperature by a temperature sensor to serve as the temperature of the body membrane, automatically reading a standard value of the speed of the body membrane at the corresponding temperature by an upper computer, and correcting the coefficient calculated by the SOS;

s2, setting of excitation voltage and receiving gain

g of the receiving gain _{Gain of} The values were chosen as follows:

s3, correcting SOS value and acquiring bone density

Coating coupling agent on the surface of the object to be detected, and coating selected V _Excitation And G _{Gain of} Under the working mode, the end part of a bone density measuring instrument where the ultrasonic probe is positioned is contacted with an object to be detected, the upper computer can display the ultrasonic sound velocity value of the bone corresponding to the detected position in real time, simultaneously detect and acquire the body temperature of the human body according to the temperature sensor, select correction factors of different body temperatures to the sound velocity of the bone, and then measure the ultrasonic sound velocity valueThe speed of sound is corrected to obtain the SOS value and the bone density value.

2. The method of bone density measurement with SOS correction and adapted for different physical examination of claim 1, wherein: in S2, a in formula (1) is 0 to 0.6; b in the formula (2) is 0 to 0.6.

3. The method of bone density measurement with SOS correction and adapted for different physical examination of claim 1, wherein: in S3, when the temperature sensor detects that the temperature of the target changes from t0 to t, the time shift of the sound wave before and after the temperature change changes corresponding to the bone at the depth z as follows:

where L is the distance the ultrasound propagates in the bone and Δ T is the time the originally measured sound wave propagates in the bone.

4. The method of bone density measurement with SOS correction and adapted for different physical examination of claim 1, wherein: the ultrasonic probe comprises one or more groups of ultrasonic transducers, wherein each group of ultrasonic transducers comprises two ultrasonic transducers, one ultrasonic transducer is communicated with the adjustable excitation module, and the other ultrasonic transducer is communicated with the adjustable receiving module; each group of two ultrasonic transducers are oppositely spaced, and the extension directions of the two ultrasonic transducers are intersected.

5. The method of bone density measurement with SOS correction and adapted for different physical examination of claim 4, wherein: the working frequency of the ultrasonic probe is 1 MHz-3 MHz; the end face of the shell is a plane, and each group of two ultrasonic transducers and the end face form an inclined angle of 15-35 degrees.

6. The method of bone density measurement with SOS correction and adapted for different physical examination of claim 5, wherein: and forming a coating shielding layer on the periphery of the end part of the ultrasonic transducer of the ultrasonic probe, wherein the coating shielding layer is abutted against the inner wall of the end part of the shell and forms a noise and electromagnetic interference prevention area, and one or more groups of ultrasonic transducers are all positioned in the coating shielding layer.

7. The method of bone density measurement with self-contained SOS correction and adapted for different physical examination of claim 1, wherein: the adjustable excitation module adopts a series resonance circuit, and the amplitude of the formed excitation pulse is in direct proportion to the excitation voltage of the ultrasonic transducer.

8. The method of bone density measurement with self-contained SOS correction and adapted for different physical examination of claim 1, wherein: the adjustable receiving module adopts a differential amplifying circuit to realize one gain adjustment change of 0-60dB, and the differential amplifying circuit comprises two variable gain amplifiers with different modulation accuracies, wherein the two variable gain amplifiers form cascade connection.

9. The method of bone density measurement with self-contained SOS correction and adapted for different physical examination of claim 8, wherein: the adjustable receiving module further comprises a filter arranged on the differential amplifying circuit.

10. The method of bone density measurement with SOS correction and adapted for different physical examination of claim 1, wherein: the control processing module is in information interaction with the upper computer, the upper computer comprises a BMI index input module of human physiological parameters, the control processing module is used for receiving information input by the BMI index input module and processing the information to form command signals for controlling the triggering time and the triggering period of the pulse, the adjustable excitation module is in information interaction with the control processing module, and the amplitude of the excitation pulse is changed synchronously with the command signals.