KR100581229B1 - Method for Measuring the Density of Shinbone by Using Lamb Wave - Google Patents

Abstract

The present invention relates to a bone density measurement device and a method for measuring tibia using lamb wave,

Converting the electrical signal into a lamb wave and irradiating the tibia in a longitudinal direction; Converting the lamb wave transmitted over a predetermined distance into an electrical signal; Converting the electrical signal into a time function; Calculating a speed of a lamb wave by analyzing the electrical signal converted into the time function; Since the bone density measurement method of the tibia using lamb wave, characterized in that it comprises a step of measuring the bone density from the speed of the lamb wave, and characterized in that the device for performing this,

Since bone density is measured by irradiating ram waves to the tibia of the human body, which is made of cortical bone, the risk of fracture can be predicted early and there is an advantage of not receiving harmful radiation to the human body.

Description

Method for Measuring Bone Mineral Density of Tibia Using Lamb's Feet {Method for Measuring the Density of Shinbone by Using Lamb Wave}

1 is a view showing a Bone Mineral Density (BMD) measuring apparatus using a lamb wave according to the present invention.

FIG. 2 is a graph showing the time of the lamb wave transmitted in the longitudinal direction of the tibia.

<Description of Major Reference Signs>

11: ultrasonic transducer for transmission 12: ultrasonic transducer for reception

13: ultrasonic transmitter 14: ultrasonic receiver

15: signal processing module 16: calculation module

17 display unit

The present invention relates to a method for measuring bone density of tibia using lamb wave, and in particular, to measure bone density by transmitting and analyzing lamb wave in the longitudinal direction to the tibia of a human body made of cortical bone (cortical bone) and diagnosing osteoporosis. It is about how to.

Osteoporosis is a disease in which bone fractures can easily occur as a result of bone loss due to bone loss and bone structure microstructure destruction. Up to a decade ago, osteoporosis could only be diagnosed by X-ray findings after fractures of the thigh, radial or spine, or severe bone loss. As such, due to the delayed diagnosis of osteoporosis, most treatment effects could not be expected even if the treatment was started, and fractures could hardly be avoided at any moment. Therefore, the prevention of osteoporosis has naturally been emphasized, and the prevention of the development of appropriate diagnostic devices for early detection of the disease is required.

Among such diagnostic devices, the above-mentioned simple X-ray imaging method may be used as a diagnostic means using radiation irradiation, which is a test capable of seeing severe loss of bone due to osteoporosis at a relatively low cost. However, according to this method, diagnosis can be made only after at least 30% of bone loss has occurred, and it was impossible to observe the treatment effect determination after 1-2 years of drug administration.

On the other hand, as osteoporosis is very important not only in the diagnosis and treatment of patients but also in the economics of medical insurance, attention has been paid to the development of methods to screen inexpensively for as many patients as possible. Accordingly, instead of using isotopes as an energy source, a Dual Energy X-ray Absorptiometry, which can generate and directly radiate dual energy radiation directly from the device itself, similar to a general X-ray imaging machine: DEXA) has been developed and is currently most widely used at home and abroad.

In addition, quantitative computed tomography (QCT) is known, which has been installed in many hospitals by installing an auxiliary device with a built-in reference material indicating progressively higher density from low density, It is a device designed to compare and quantify a patient's bone density. However, the measurement time is longer than the BMD, the accuracy is poor in the elderly, radiation exposure, compared to the bone density meter, it is difficult to see several bones of the spine at the same time, and also took a lot of time taken.

Such a method using the above-mentioned irradiation can have a harmful effect on the human body in common.

However, the diagnosis of osteoporosis using ultrasound, which has recently attracted a lot of attention, has little risk to the human body compared to X-rays, and the ultrasound diagnostic equipment has the advantages of being easy to use and inexpensive. It is very advantageous not only for patients but also for health insurance expenses. By the way, the bone density meter using ultrasonic waves, which are widely used in hospitals, is transmitted to the calcaneus of the human body consisting mostly of cancellous bones, and thus the speed of sound (SOS) and the broadband ultrasonic attenuation. : Method of measuring bone density and diagnosing osteoporosis by measuring BUA), and the method of accurately measuring bone density of cortical bone, which is the first occurrence of fracture, has not been disclosed. In addition, the measurement error according to the thickness of the calcaneus and the surrounding skin tissue, the calcaneal of the calcaneus, the position of the foot and the angle of ultrasound incidence and the lack of reproducibility had limitations in accurate diagnosis of osteoporosis.

The present invention has been made to use the advantages of the above-mentioned ultrasonic diagnostic equipment and to overcome the limitations of the prior art, the object of the invention is to measure the speed of the ram wave by transmitting the ram wave in the longitudinal direction to the tibia of the human body made of cortical bone, It is to provide a bone density measurement method excellent in measurement accuracy and reproducibility.

In order to achieve the above object, the bone density measurement device of tibia using lamb wave according to the present invention,

An ultrasonic transmitter for generating an ultrasonic electric signal;

A transmission ultrasonic transducer for converting the electrical signal into a lamb wave;

An ultrasonic receiver for receiving lamb wave from the ultrasonic transmitter for transmission;

A receiving ultrasonic transducer for converting the lamb wave from the ultrasonic receiver into an electrical signal;

A signal processing module for converting the electrical signal converted by the receiving ultrasonic transducer into a time function;

A calculation module for calculating a speed and bone density of a lamb wave from the electrical signal converted by the signal processing module;

It characterized in that it comprises a display unit for displaying the calculation and diagnostic results obtained in this way.

Further, in the calculation module, the speed of the lamb wave and the bone density are set in a linear relationship.

In addition, it is preferable that a connection device is interposed between the transmitting ultrasonic transducer and the receiving ultrasonic transducer, so that the gap between them is fixed.

On the other hand, as a bone density measurement method of tibia using lamb wave according to the present invention,

Converting the electrical signal into a lamb wave and irradiating the tibia in a longitudinal direction;

Converting the lamb wave transmitted over a predetermined distance into an electrical signal;

Converting the electrical signal into a time function;

Calculating a speed of a lamb wave by analyzing the electrical signal converted into the time function;

And measuring the bone density from the speed of the lamb wave.

Here, it is preferable to further include the step of diagnosing osteoporosis by comparing the bone density measurement with the database of the average bone density.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 shows a bone density measuring apparatus using a broadband band ultrasonic reflectance according to the present invention, the bone density measuring apparatus is a transmission ultrasonic transducer 11 for converting an electrical signal into a lamb wave, and a receiving for converting a lamb wave into an electrical signal An ultrasonic transducer 12, an ultrasonic transmitter 13 for driving the transmitting ultrasonic transducer 11, an ultrasonic receiver 14 for driving the receiving ultrasonic transducer 12, and the ultrasonic receiver 14 A signal processing module 15 for converting the electrical signal driven by the step into a time function, and a calculation module 14 for calculating the speed and bone density of the lamb wave by analyzing the converted electrical signal in the signal processing module 15. And a display unit 15 for displaying the calculation and diagnosis results on the screen. Since each of the ultrasonic transducer, the ultrasonic transceiver, and the like is a commonly used component, a specific example of the apparatus is not described.

First, the transmitting ultrasonic transducer 11 shown in FIG. 1 is manufactured to have a broadband frequency response characteristic of a 200 kHz center frequency and a diameter of 25.4 mm. In addition, a fixing device for connecting the two ultrasonic transducers may be used so that the distance between the transmitting ultrasonic transducer 11 and the receiving ultrasonic transducer 12 is fixed during measurement for the reliability and reproducibility of the lamb wave velocity measurement. Examples of the fixing device include a frame formed of plastic, and two ultrasonic transducers may be installed through the frame.

The ultrasonic transmitter 13 and the ultrasonic transducer 11 for transmission 11 generate ultrasonic bursts having a frequency of 200 kHz and a constant length. The ultrasonic wave irradiated in the longitudinal direction to the tibia of FIG. 1 is transmitted with the characteristic of the lamb wave whose propagation speed changes according to the thickness of the cortical bone constituting the tibia.

The electrical signal of the lamb wave driven by the receiving ultrasonic transducer 12 and the ultrasonic receiver 14 of FIG. 1 is converted into a time function in the signal processing module 15.

FIG. 2 is a graph showing a waveform as a time function of a lamb wave transmitted when the distance between the transmitting ultrasonic transducer 11 and the receiving ultrasonic transducer 12 is 50 mm in order to measure the speed of the lamb wave. Since obtaining the speed of the lamb wave from the waveform of FIG. 2 is a very general process, detailed description is omitted. In addition, the distance (50 mm) described above is only one experimental example for obtaining the time function waveform of the lamb wave, and it will be obvious that the time function waveform of the lamb wave varies with distance.

Since the speed of the lamb wave depends on the bone density of the cortical bone, it can be used as a variable reflecting the bone density change sensitively. Accordingly, it is possible to analyze the correlation between the measured lamb wave speed and the measured bone density of the tibia directly, which is possible through the simple regression analysis of the lamb wave speed and bone density. As a result of the experiment, the following relational expression can be obtained, and the bone density can be easily obtained from the ram wave speed. Of course, these correlations require several experiments to achieve reliability.

BMD = 0.63 SOS-6.52

Where BMD is the bone density of the tibia and SOS is the velocity of the lamb wave. In this case, the coefficients (0.63) and constants (-6.52) are used in the conventional method of obtaining the respective residuals for a large number of experimental data on BMD and SOS, and the slope and intercept to minimize the sum of squares of the residuals. Depended on

In the display unit 17 of FIG. 1, the T-score (compared to the average bone density of a young adult) and Z-score (compared to the average bone density of the same age group) as well as the lamb wave speed and bone density measurement results. The osteoporosis diagnosis result is displayed on the screen.

In the case of osteoporosis patients, the rate of lamb wave is very different from that of normal people due to the decrease of bone loss and cortical bone thickness due to bone loss, and the bone density is calculated from the linear correlation between the measured lamb wave rate and bone density. Therefore, osteoporosis can be easily diagnosed by comparing the average BMD of the databased young adults, the average BMD of the same age group, and the BMD calculated from the speed of lamb wave.

According to the present invention having the above-described configuration, it can be said that it is very effective to predict the risk of fracture early because the bone density of the cortical bone is measured by irradiating lamb wave to the tibia of the human body made of cortical bone.

In addition, there is an advantage that does not receive harmful radiation to the human body.

In addition, the bone density measurement method of the present invention has the advantage that not only the measurement method is simple but also the measurement time is short, so that the diagnosis result can be quickly known, the portable device of the measuring device can be easily carried out, and the patient can be examined inexpensively as much as possible. .

Claims (5)

delete delete delete Converting the electrical signal into a lamb wave and irradiating the tibia in a longitudinal direction; Converting the lamb wave transmitted over a predetermined distance into an electrical signal; Converting the electrical signal into a time function; Calculating a speed of the lamb wave (SOS) by analyzing the electrical signal converted into the time function; Obtaining the bone mineral density (BMD) of the tibia by the equation BMD = 0.63 SOS-6.52 from the speed of the lamb wave (SOS); Bone density measurement method of tibia using lamb wave, characterized in that comprising a. The method of claim 4, wherein Diagnosing osteoporosis by comparing the bone density measurements with the averaged bone density in the database, the bone density measurement method of the tibia using lamb wave, characterized in that it further comprises.

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