KR101637088B1 - Method and apparatus for estimating bone mineral density using a time reversal acoustic focusing technique - Google Patents

Abstract

The present invention relates to an apparatus and method for predicting bone density using a time reversal acoustic focusing technique, and an apparatus for predicting bone density using the time reversed acoustic focusing technique of the present invention includes an ultrasonic transmitter for irradiating ultrasonic waves; An ultrasonic wave receiving unit for receiving the ultrasonic wave irradiated from the ultrasonic wave transmitting unit; A time inverting unit for providing time-inverted ultrasonic waves to the ultrasonic transmitting unit; A converting unit for converting the ultrasonic wave received by the ultrasonic wave receiving unit into an electric signal; A signal processing unit for detecting the electrical signal converted by the ultrasonic conversion unit; And an operation unit for analyzing the electrical signal detected by the conversion unit to calculate a sound velocity of an ultrasonic wave passing through the spongy bone and for predicting a bone density of the spongy bone through a sound velocity of the calculated ultrasonic wave; . ≪ / RTI >
According to the present invention, since bone mineral density is predicted using harmless ultrasound to the human body, damage such as radiation exposure due to measurement using conventional radiation is not generated, and the human body is relatively safe, It is possible to obtain the sound velocity for each region of interest by dividing the region of interest into multiple regions of interest and transmitting the pulsed ultrasonic waves focused on each region of interest using the time reversed acoustic focusing technique and obtaining the bone density image It is possible to predict the bone density with higher accuracy.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and a method for predicting bone mineral density using time-

The present invention relates to an apparatus and a method for predicting bone density using time reversed sound focusing techniques.

Recently, the number of patients with degenerative osteoporosis is also increasing as the standard of living improves, medicine develops, life expectancy increases, and the elderly population increases.

Degenerative osteoporosis is reported to be caused by osteoporosis in skeletal volume reduced by 10% of the total population in the United States. The annual incidence of osteoporosis-related fractures increases and the annual medical expenses are increasing.

In the case of osteoporosis, fracture can be caused by a small impact due to a decrease in bone mineral density below the fracture threshold. In the case of the elderly, fracture is a major cause of death, and prevention is very important. Therefore, development of equipment for verifying bone density is required It is true.

To this end, in Korean Patent Registration No. 10-1053438 (filed on August 22, 2009, registered on July 27, 2011, hereinafter referred to as "prior art"), a radioisotope emitting two or more gamma- To measure bone mineral density.

However, such a conventional technique has a problem that it is inevitable that a patient is exposed to radiation because high-energy radiation is required to measure bone density per unit area.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a technique for predicting bone density without using radiation in measuring bone density.

In order to achieve the above object, the present invention provides an apparatus for predicting bone density using a time-reversed acoustic focusing technique, comprising: an ultrasonic transmitter for irradiating ultrasound; An ultrasonic wave receiving unit for receiving the ultrasonic wave irradiated from the ultrasonic wave transmitting unit; A time inverting unit for providing time-inverted ultrasonic waves to the ultrasonic transmitting unit; A converting unit for converting the ultrasonic wave received by the ultrasonic wave receiving unit into an electric signal; A signal processing unit for detecting the electrical signal converted by the ultrasonic conversion unit; And an operation unit for analyzing the electrical signal detected by the conversion unit to calculate a sound velocity of an ultrasonic wave passing through the spongy bone and for predicting a bone density of the spongy bone through a sound velocity of the calculated ultrasonic wave; . ≪ / RTI >

The ultrasonic transmission unit may further include a reverberation part coupled to the ultrasonic wave irradiation direction to multiply reflect the ultrasonic waves irradiated by the ultrasonic wave transmission unit.

Here, the reverberation portion may be an aluminum plate having a thickness of 15 to 25 mm.

In addition, the calculation unit may predict the bone mineral density of the spongy bone using the linear relationship between the sonic velocity of the ultrasonic wave passing through the caustic bone and the bone mineral density value of the caustic bone.

The apparatus for predicting bone density using the time reversal sound focusing technique may further include an output unit for outputting a sound velocity and a bone density prediction result of ultrasonic waves having passed through the spongy bone formed by the calculation unit; As shown in FIG.

Meanwhile, the method of predicting bone density using the time-reversed acoustic focusing technique of the present invention comprises: an ultrasonic wave irradiation step in which an ultrasonic wave transmitting unit irradiates an ultrasonic wave;

A conversion step of receiving the ultrasonic wave irradiated in the ultrasonic wave irradiation step from the ultrasonic wave receiving unit and converting the received ultrasonic wave into an electric signal; And

(SOS) of an ultrasonic wave through the electric signal converted by the operation unit in the conversion step,

The calculation step may include calculating the difference in reception time between an electrical signal detected from the ultrasonic waves passing through the spongy bone in the conversion step and an electrical signal detected from the ultrasonic waves irradiated in a state in which the spongy bone is not positioned, And predicting the bone mineral density of the spongy bone through the sonic velocity of the passed ultrasound.

Here, the step of irradiating the ultrasound waves may be a step of irradiating focused ultrasound waves generated by time-reversing the ultrasound waves reflected by the ultrasonic wave transmitter in the time reversing unit.

The calculating step may include: a sonic velocity calculating step of calculating a sonic velocity (SOS) of the ultrasonic wave through the electrical signal converted in the converting step; And a bone mineral density prediction step of predicting the bone mineral density of the spongy bone using the correlation between the sonic velocity of the ultrasonic wave passing through the spongy bone calculated in the sound velocity calculation step and the bone mineral density of the spongy bone, The correlation between the sonic velocity of the ultrasonic wave passing through the cavernous bone and the bone mineral density of the cavernous bone is linearly proportional to the sonic velocity of the cavernous bone passing through the cavernous bone, Lt; / RTI >

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The method of predicting bone density using the time reversed acoustic focusing technique may further include outputting a sound velocity and a bone density prediction result of the ultrasonic wave having passed through the spongy bone calculated in the calculation step.

As described above, the present invention has the following effects.

First, since the bone density is predicted using ultrasonic waves which are harmless to the human body, the human body is relatively safe because no damage such as radiation exposure due to measurement using conventional radiation occurs.

Second, the sonographic velocity of each region of interest can be obtained by dividing the calcaneal cross-section into multiple regions of interest and transmitting the focused pulsed ultrasonic waves to each region of interest using the time reversed acoustic focusing technique. , It is possible to obtain a bone density image for the cross section of the calcane bone, so that it is possible to predict the bone density with higher accuracy.

FIG. 1 is a schematic view of an apparatus for predicting bone density using a time inversion sound focusing technique according to an embodiment of the present invention.
FIG. 2 shows a focused ultrasound signal generated through the reverberation part and the time reversal part of the present invention.
3 is a graph showing ultrasonic signals that have passed through the cavernous bone and ultrasound signals that have not passed through the cavernous bone.
FIG. 4 is a graph showing the correlation between the sonic velocity of ultrasonic waves passing through spongy bone samples and the bone mineral density of spongy bone samples.
FIG. 5 is a flowchart illustrating a method of predicting bone density using a time inversion sound focusing technique according to an embodiment of the present invention.

The preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings, in which the technical parts already known will be omitted or compressed for simplicity of explanation.

<Time reversal Acoustic focus  Technology for the prediction of bone mineral density>

FIG. 1 is a schematic view of an apparatus for predicting bone density using a time inversion sound focusing technique according to an embodiment of the present invention.

An apparatus 100 for predicting bone density using a time inversion sound focusing technique according to an embodiment of the present invention includes an ultrasonic transmission unit 110, an ultrasonic reception unit 120, a time reversal unit 130, a conversion unit 140, a signal processing unit 150, an operation unit 160, and an output unit 170.

The ultrasonic transmission unit 110 is located in the water and can irradiate ultrasonic waves to the cavernous bone B.

Here, the cavernous bone B to which the ultrasonic transmission unit 110 irradiates the ultrasonic wave is preferably a human heel bone, that is, a calf bone having an anatomical structure that allows easy penetration of ultrasonic waves.

The ultrasonic receiving unit 120 is located in the water and can receive the ultrasound waves irradiated by the ultrasonic transmitting unit 110 and passed through the cavernous bone B.

Here, the ultrasonic transmission unit 110 and the ultrasonic reception unit 120 may use transducers for transmitting and receiving transducers, respectively, and may have a center frequency of 0.5 MHZ.

The ultrasonic transmission unit 110 may further include a reverberation part 112 coupled with the ultrasonic wave irradiation direction of the ultrasonic transmission unit 110 so that ultrasonic waves having a long reverberation time can be irradiated.

An ultrasonic wave irradiated from the ultrasonic wave transmitting unit 110 is transmitted through the aluminum plate, and the ultrasonic waves are multiply reflected in the aluminum plate, so that the aluminum plate It is possible to have a longer reverberation time than an ultrasonic wave to be irradiated without passing through.

The time reversing unit 130 may provide the ultrasonic transmission unit 110 with the time-reversed electrical signal obtained by converting the ultrasonic signal received from the ultrasonic transmission unit 120 by the conversion unit 140, do.

The signal a shown in FIG. 2 represents an ultrasonic signal having a long reverberation time while the ultrasonic wave irradiated by the ultrasonic transmitter 110 located in the water is reflected by being reflected by the reverberation portion 112.

The signal b is a signal generated by inverting the time (Time) corresponding to the vertical axis of FIG. 2 of the signal a received by the ultrasonic receiving unit 120 by the time inverting unit 120.

Here, it can be confirmed that the signal b is symmetric with respect to the signal a in the vertical axis time '0', and the signal b is the time-inverted signal of the signal a.

The signal c indicates the ultrasonic signal received by the ultrasonic wave receiving unit 120 when the signal b generated in the time inverting unit 130 is irradiated through the ultrasonic wave transmitting unit 110. [

That is, the time inverting unit 130 receives the ultrasound signal a transmitted from the ultrasound receiving unit 120 through the reverberation portion 112 of the ultrasound transmitting unit 110, and outputs the ultrasound signal b and provides the generated ultrasonic signal to the ultrasonic transmission unit 110 so that the ultrasonic transmission unit 110 can irradiate the focused ultrasonic waves in time.

The converting unit 140 may convert the ultrasound signals received by the ultrasound receiving unit 120 into electrical signals.

Here, the converting unit 140 converts an electrical signal into an ultrasonic wave to cause the ultrasonic wave receiving unit 120 to irradiate the ultrasonic wave. When the ultrasonic wave receiving unit 120 receives the ultrasonic wave irradiated from the ultrasonic wave transmitting unit 110, 140 to an electric signal and transmits the ultrasonic wave to the time inverting unit 130 or the signal processing unit 150.

The signal processing unit 150 may detect the ultrasonic signal converted into the electrical signal by the converting unit 140. [

Here, the signal processor 150 detects an electrical signal transmitted from the converting unit 140, and amplifies and filters the detected electrical signal.

FIG. 3 is a graph showing an ultrasonic signal passing through the cavernous bone and an ultrasonic signal not passing through the cavernous bone, and FIG. 4 is a graph showing a correlation between the sonic velocity of the cavernous bone and the bone mineral density of the cavernous bone.

The calculation unit 160 analyzes the electrical signal detected by the signal processing unit 150, calculates the sound velocity of the ultrasonic wave from the electrical signal, and predicts the bone density of the spongy bone B through the calculated sound velocity.

A signal having a large amplitude among the two ultrasonic signals shown in FIG. 3 is transmitted to the ultrasonic wave receiving unit (not shown) when the ultrasonic wave transmitted from the ultrasonic wave transmitting unit 110 is in the water The signal having a small amplitude is a signal received by the ultrasonic wave receiver 12 after the ultrasonic wave irradiated by the ultrasonic wave transmitter 110 passes through the caustic bone B.

At this time, the arithmetic unit 160 may measure the difference in the reception time of the two signals received by the ultrasonic receiver 120 and calculate the sonic velocity of the ultrasonic wave that has passed through the cavernosal bone B.

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The calculation unit 160 may calculate the correlation between the sonic velocity of the ultrasonic wave that has passed through the spongy bone sample BS previously confirmed through the spongy bone sample BS and the bone mineral density of the spongy bone sample BS, B, the bone mineral density of the caustic bone B can be predicted through the sonic velocity of the ultrasonic waves, which will be described with reference to FIG.

In the graph of FIG. 4, the Y axis represents the sound of speed (SOS), the X axis represents the bone mineral density of the spongy bone sample (BS), and the small femoral spongy bone is used as the spongiform bone sample (BS).

Here, the ultrasonic sound velocity of 14 sponge bone samples (BS) was measured, and the average value of each ultrasonic sound velocity passing through 10 areas by designating 10 areas in each spongy bone sample (BS) , And bone mineral densities of 14 sponge bone samples (BS) were measured.

The black solid line with positive slope in FIG. 4 is a linear regression of the mean value of the ultrasonic sound velocity passed through 14 spongy bone samples (BS), and the sonic sound velocity measured from the 14 spongy bone samples is the small femoral spongy bone sample It is confirmed that there is a positive correlation with the bone mineral density of the BS.

The sonic velocity of the ultrasound passed through the spongy bone (B) measured through the bone mineral density predicting apparatus (100) using the time reversal sound focusing technique through the Pearson correlation coefficient R value obtained by the linear regression analysis is 0.92 It can be seen that the bone mineral density of the cavernous bone (B) has a very high correlation.

Accordingly, the operation unit 160 can predict the bone mineral density of the cavernosal bone B through the ultrasonic sound velocity passed through the cavernous bone B.

The output unit 170 can output the bone density of the cavernous bone and the sonic velocity of the ultrasonic wave that has passed through the cavernous bone B calculated by the calculator 160. [

Here, the output unit 170 may include a monitor (not shown), a printer (not shown) for outputting the results of bone mineral density prediction of the spongial bone and the sonic velocity of the ultrasonic wave that have passed through the cavernosal bone B calculated by the calculation unit 160, (Not shown), but it is not limited thereto.

<Time reversal Acoustic focus  Technique for predicting bone mineral density>

FIG. 5 is a flowchart illustrating a method of predicting bone density using a time inversion sound focusing technique according to an embodiment of the present invention.

1. Ultrasonic irradiation step < S100 >

In the ultrasound irradiation step S100, the ultrasound transmitting unit 110 irradiates focused ultrasound to the cavernosal bone B.

The ultrasound receiving unit 120 receives the multiple reflected ultrasound waves irradiated by the ultrasound transmitting unit 110 located in the initial water and is transmitted to the converting unit 140. The converting unit 140 converts the received ultrasound signals into electrical signals And transmits it to the time reversing unit 130. [

Then, the time inverting unit 130 generates a focused ultrasonic wave by inverting the electric signal received from the changing unit 120 for a time, and transmits the focused ultrasonic wave to the ultrasonic transmitting unit 110.

Thereafter, the ultrasonic transmission unit 110 may irradiate focused ultrasonic waves to the cavernous bone B.

At this time, in order to generate an ultrasonic sound velocity value in the water, the ultrasonic transmission unit 110 may irradiate focused ultrasonic waves before positioning the caudal bone B.

Before the ultrasonic irradiation step S100, the ultrasonic sound velocity passed through the caustic bone sample (BS) and the bone mineral density of the caustic bone sample (BS) are measured, and the ultrasonic sound velocity passing through the caustic bone sample (BS) A correlation step between the bone mineral density of the caustic bone B and the ultrasonic sound velocity passing through the caustic grit bone B should be preceded by the step of deriving the correlation between the bone density of the caustic bone B and the bone mineral density of the caustic bone B,

2. Conversion step < S200 >

In the conversion step S200, when the ultrasonic wave receiving unit 120 receives ultrasonic waves irradiated from the ultrasonic wave transmitting unit 110 in the ultrasonic wave irradiation step S100, the converting unit 140 converts the ultrasonic waves into electrical signals, To the signal processor 150.

Thereafter, the signal processing unit 150 obtains only signals useful for amplifying the received electrical signal, filtering the noise to calculate the bone structure, and transmitting the electrical signal, which has been preprocessed through the signal processing unit 150, to the operation unit 160 have.

3. Operation step < S300 >

The operation step S300 is a step in which the operation unit 160 calculates the sound velocity of the ultrasonic wave through the electric signal received from the signal processing unit 150 in the conversion step S200 and calculates the bone density of the spongy bone B by the calculated sonic sound velocity Prediction.

Here, the operation unit 160 may calculate the sound velocity of the ultrasonic wave that has passed through the caudal bone B through the electrical signal converted in the conversion step S200.

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Using the correlation between the ultrasonic sound velocity passed through the caustic bone B obtained through the caustic bone sample BS and the bone density of the caustic bone B in advance, the calculating unit 160 calculates a difference between the sonic velocity of the calculated ultrasonic waves The bone mineral density of the caustic bone B can be predicted.

Thereafter, an output step of outputting the sonic velocity and the bone mineral density prediction result of the ultrasonic wave passing through the spongy bone calculated in the calculation step (S300) through the output unit 170 may be further included.

As a result, the present invention uses ultrasonic waves that are harmless to the human body, unlike the method of measuring bone density, which irradiates high-energy radiation to a patient's measurement site. Therefore, It is possible to minimize the rejection and physical damage of the patient according to the time of the ultrasound signal and to reverse the time of the ultrasound signal having a long reverberation time to generate the focused ultrasound wave so that the time- Since it is possible to obtain the bone density images of the corresponding calcaneal sections by calculating the sound velocity of the ultrasonic waves in each region by dividing a single calcaneal section into a plurality of regions of interest, the time reversal sound focusing technique capable of accurately measuring the bone density can be performed An apparatus and a method for predicting bone density are provided.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. And the scope of the present invention should be understood as the following claims and their equivalents.

100: Bone density prediction device using time convergence acoustic focusing technique
110: Ultrasonic transmitter
112:
120: Ultrasound receiver
130: half an hour
140:
150: Signal processor
160:
170:
B: spongiform bone
BS: Spongy bone sample

Claims (10)

An ultrasonic transmitter for irradiating ultrasonic waves;
An ultrasonic wave receiving unit for receiving the ultrasonic wave irradiated from the ultrasonic wave transmitting unit;
A time inverting unit for providing time-inverted ultrasonic waves to the ultrasonic transmitting unit;
A converting unit for converting the ultrasonic wave received by the ultrasonic wave receiving unit into an electric signal;
A signal processing unit for detecting the electrical signal converted by the ultrasonic conversion unit; And
And an operation unit for analyzing the electrical signal detected by the ultrasonic transducer unit to calculate the sonic velocity of the ultrasonic wave passing through the spongy bone and for predicting the bone density of the spongy bone through the sonic velocity of the ultrasonic wave,
The ultrasonic transmission unit includes:
And a reverberation part coupled to the ultrasonic wave irradiation direction for multiply reflecting the ultrasonic wave irradiated from the ultrasonic wave transmitter part
Bone Density Prediction System Using Time Inverse Acoustic Focusing Technique.
delete The method according to claim 1,
Wherein the reverberation portion is an aluminum plate having a thickness of 15 to 25 mm
Bone Density Prediction System Using Time Inverse Acoustic Focusing Technique.
The method according to claim 1,
Wherein the calculation unit predicts the bone mineral density of the spongy bone using the fact that the sonic velocity of the ultrasonic wave that has passed through the spongy bone is proportional to the bone mineral density of the spongy bone,
Bone Density Prediction System Using Time Inverse Acoustic Focusing Technique.
The method according to claim 1,
The apparatus for predicting bone density using the time-reversed sound focusing technique comprises:
An output unit for outputting a sound velocity and a bone density prediction result of ultrasonic waves having passed through the spongy bone formed by the operation unit; &Lt; RTI ID = 0.0 &gt;
Bone Density Prediction System Using Time Inverse Acoustic Focusing Technique.
An ultrasonic wave irradiation step in which the ultrasonic wave transmission unit irradiates ultrasonic waves;
A conversion step of receiving the ultrasonic wave irradiated in the ultrasonic wave irradiation step from the ultrasonic wave receiving unit and converting the received ultrasonic wave into an electric signal; And
(SOS) of an ultrasonic wave through the electric signal converted by the operation unit in the conversion step,
Wherein the ultrasonic wave irradiation step is a step of irradiating the focused ultrasonic wave generated by time reversal of the ultrasonic wave reflected by the ultrasonic wave transmitting part in the time inverting part,
The calculation step may include calculating the difference in reception time between an electrical signal detected from the ultrasonic waves passing through the spongy bone in the conversion step and an electrical signal detected from the ultrasonic waves irradiated in a state in which the spongy bone is not positioned, And predicting the bone mineral density of the spongy bone through the sonic velocity of the ultrasound wave
A Method of Predicting Bone Mineral Density Using Time Inverse Acoustic Focusing Technique.
delete The method according to claim 6,
Wherein,
A sound velocity calculating step of calculating a sound velocity (SOS) of an ultrasonic wave through the electrical signal converted in the conversion step; And
And a bone mineral density prediction step of predicting the bone mineral density of the spongy bone using the correlation between the sonic velocity of the ultrasonic wave that has passed through the spongy bone and the bone mineral density of the spongy bone,
The correlation between the sonic velocity of the ultrasonic wave passing through the cavernous bone and the bone mineral density of the cavernous bone in the bone mineral density prediction step is such that the sonic velocity of the cavernous bone passing through the cavernous bone is linearly proportional to the bone mineral density of the cavernous bone And a positive (+) linear relationship.
A Method of Predicting Bone Mineral Density Using Time Inverse Acoustic Focusing Technique.
delete The method according to claim 6,
The method of predicting bone density using the time inversion sound focusing technique comprises:
And outputting the sonic velocity and the bone mineral density prediction result of ultrasonic waves having passed through the spongy bone formed in the calculation step
A Method of Predicting Bone Mineral Density Using Time Inverse Acoustic Focusing Technique.

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