JP2007020998A - Ultrasonic diagnostic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonograph capable of differentiating characteristics of tissues in a living body only by ultrasonic measurement. <P>SOLUTION: A computing part 3 computes a moving speed or moving displacement of living tissues and a distortion variation by using signals from a transmitting and receiving part 2. A frequency analyzing part 4 performs a frequency analysis calculation on both the moving speed or the moving displacement of the living tissues and the coherence of the distortion variation which are obtained by the computing part 3 and a transfer function. A resonance element detecting part 5 detects the elements of vibrations due to resonances on the moving speed or the moving displacement of the living tissues, and the distortion variation based on the result determined by the frequency analyzing part 4. A tissue property differentiating part 6 differentiates the living tissues from a resonance frequency of the living tissues detected by the resonance element detecting part 5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus that measures a shape characteristic or a characteristic characteristic of a living tissue using ultrasonic waves.

  As one of means for identifying and identifying the properties of the tissue in the living body, as shown in Patent Document 1, the elastic modulus is adjusted according to the elastic fiber, collagen fiber, fat, thrombus, etc. constituting the tissue in the living body. A method for obtaining the elastic modulus from the strain when stress is applied to the tissue in the living body by utilizing the difference is known.

  On the other hand, as shown in Patent Document 2 or Patent Document 3, when a hardness sensor that resonates a piezoelectric element is pressed against the surface of a living tissue, the impedance of the piezoelectric element depends on the hardness of the living tissue. There is a known technique for detecting the hardness of a living tissue by utilizing the fact that the resonance frequency of the piezoelectric element or the output voltage changes.

Japanese Patent Laid-Open No. 10-5226 JP-A-1-290529 Japanese Patent Laid-Open No. 10-216124

  As a method for obtaining the elastic modulus from the strain when stress is applied to the tissue in the living body, for example, when obtaining the elastic modulus of the arterial wall, as shown in Patent Document 1, means for measuring strain by an ultrasonic diagnostic apparatus In addition, a plurality of measuring means of stress measuring means using a sphygmomanometer are required, and parts that can be measured by a plurality of measuring means are limited, and in particular, a part of a living body to which a sphygmomanometer can be applied is limited to the upper arm or the like Therefore, the stress and strain measurement parts need to be the same part, and therefore, the part where the ultrasonic strain measurement is performed is limited to the part where the sphygmomanometer can be applied.

  Also, as shown in Patent Documents 2 and 3, a hardness sensor having a piezoelectric element resonated is pressed against the surface of a living tissue, and the fluctuation of the resonance frequency of the hardness sensor is measured to determine the hardness of the living tissue. In the method for detecting the position, the position where the hardness sensor is installed is limited to the surface of the living tissue, and measurement inside the living tissue is impossible.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ultrasonic diagnostic apparatus capable of identifying a property characteristic of a tissue inside a living body only by ultrasonic measurement.

  In general, an elastic body such as a living tissue has a natural frequency based on factors such as elastic modulus, viscosity, density, and shape. The natural frequency is also called a resonance frequency, and the elastic body resonates when vibration in a frequency band including the resonance frequency is applied. The resonance of the elastic body has resonance forms such as vibration that translates without distortion and compressive vibration that accompanies distortion.

  FIG. 5 is a graph showing the movement displacement of the arterial wall intima and adventitia (arterial wall intima movement displacement 401a and arterial wall adventitia movement displacement 401b) and the arterial wall strain change 402 according to the heartbeat. It is the schematic diagram which expanded one cardiac cycle when the resonant component of one frequency is superimposed. In FIG. 5, with respect to the time axis, one heart cycle is enlarged and displayed. If the amplitudes of the resonance components of the arterial wall intima and adventitia are the same, they are offset by the calculation to determine the amount of arterial wall distortion, and the resonance component does not appear in the amount of strain change. In the case of compressive vibration accompanied by strains having different amplitudes of resonance components, resonance components also appear in the strain change amount 402 as shown in FIG.

  FIG. 6 is a schematic diagram showing the gain characteristic of the transfer function, the amplitude square coherence function, and the reproducibility evaluation function between the movement displacement of the arterial wall intima and the movement displacement of the adventitia during one cardiac cycle. As shown in FIG. 5, when a resonance component of a single frequency is superimposed, the transfer function between the movement displacement of the arterial wall intima and the movement displacement of the adventitia accompanying the heartbeat is as shown in FIG. ).

  The frequency component of the vibration due to the change in blood pressure of the arterial wall intima movement displacement 401a and the arterial wall epicardium movement displacement 401b has an amplitude of the vibration component between the arterial intima and the adventitia due to the arterial wall distortion. There is a difference. It is known that the frequency component of the motion of the arterial wall due to the blood pressure change is a frequency band from direct current to about several tens of Hz, and is shown in the frequency band A in FIG.

  The frequency component of the vibration due to compressive resonance of the arterial wall intima movement displacement 401a and the arterial wall outer membrane movement displacement 401b is accompanied by distortion of the arterial wall. It is known that the difference in the amplitude of the component is smaller than the distortion due to the blood pressure change. Further, in the case of resonance by translation, the difference in amplitude of the vibration component is 0 between the arterial wall intima and the adventitia. The frequency component of this resonance varies depending on the subject, but exists in a higher frequency band from several tens of Hz to about one hundred Hz compared to the frequency component of arterial wall motion caused by changes in blood pressure. The frequency component of vibration due to this compressive resonance is indicated by frequency band B in FIG.

  On the other hand, as shown in FIG. 5, the coherence of the movement displacement of the arterial wall intima and epicardium accompanying the heartbeat when the resonance component of a single frequency is superimposed is as shown in FIG. It will be a thing.

  The amplitude square coherence function takes a value between 0 and 1, and is close to 1 when the relevance of the two signals is high. Therefore, when the value of the amplitude square coherence function is close to 0, it can be considered as an unrelated random noise component. As shown in FIG. 6B, the frequency band A in which the frequency component of the arterial wall motion due to blood pressure change exists, and the frequency band B in which the frequency component of vibration due to resonance exists, that is, about 100 Hz from DC. In the frequency band, the coherence value is close to 1, and the relevance between the arterial wall intima movement displacement 401a and the arterial wall epicardium movement displacement 401b is high, while the frequency band C of about 100 Hz or more. The coherence value is close to 0, indicating that it is mainly a random noise component.

  In this way, by obtaining the gain characteristics and coherence of the transfer function in the frequency domain for the movement displacement of the arterial wall intima and outer membrane accompanying the heartbeat and the distortion amount change of the arterial wall, It is possible to separate from those caused by vibration due to resonance and random noise components.

  An ultrasonic diagnostic apparatus of the present invention is an ultrasonic diagnostic apparatus that measures a shape characteristic or a characteristic characteristic of a biological tissue, and includes a speed calculation unit that calculates a movement speed of the biological tissue, and a movement displacement of the biological tissue. One of the movement displacement calculation units to be calculated, the movement speed, or the strain change amount calculation unit for calculating the strain change amount of the living tissue based on the movement displacement, the movement speed, the movement displacement, and the strain A biological tissue for at least one of the movement speed, displacement, and strain change based on a frequency analysis unit that performs frequency analysis on at least one of the changes, and a frequency characteristic analyzed by the frequency analysis unit Based on the resonance component detection unit that detects a vibration component due to its own resonance and the resonance frequency of the biological tissue detected by the resonance component detection unit, the characteristics of the biological tissue are identified. , A tissue characterization identification unit for performing those comprising.

  In the ultrasonic diagnostic apparatus of the present invention, the velocity calculation unit, the movement displacement calculation unit, and the strain change calculation unit calculate the motion for a plurality of points of interest or regions of interest set in the living tissue. Including those having the function of obtaining the spatial distribution of velocity, displacement, and strain variation.

  In the ultrasonic diagnostic apparatus of the present invention, the speed calculation unit, the movement displacement calculation unit, and the strain change amount calculation unit obtain a spatial average value of the motion speed, the movement displacement, and the strain change amount. Including those having

  In the ultrasonic diagnostic apparatus of the present invention, the frequency analysis unit includes a function of calculating a frequency spectrum of the motion speed, movement displacement, and strain change amount.

  In the ultrasonic diagnostic apparatus of the present invention, the frequency analysis unit has a function of calculating coherence between at least two points of interest of either the movement speed or the movement displacement, and the correlation between the fixed periods. Including what you want.

  In the ultrasonic diagnostic apparatus of the present invention, the frequency analysis unit has a function of calculating a reproducibility evaluation function of either the movement speed or the movement displacement, and obtains reproducibility for each frequency during a certain period. including.

  In the ultrasonic diagnostic apparatus of the present invention, the frequency analysis unit has a function of calculating a transfer function between at least two points of interest of either the movement speed or the movement displacement, and gain during a certain period. Includes those that require characteristics.

  In the ultrasonic diagnostic apparatus according to the present invention, the resonance component detection unit may perform reproducibility for each frequency of a fixed period or at least two interests of at least one of the movement speed and the movement displacement. Based on the coherence between the points for a certain period and the gain characteristics of the transfer function between the at least two points of interest, any one or all of the motion speed, displacement, and strain variation, This includes detecting vibration components due to resonance of the living tissue itself and identifying the properties of the living tissue.

  In the ultrasonic diagnostic apparatus of the present invention, the resonance component detection unit includes a band pass filter and / or a band limiting filter, which can remove signal components other than the resonance component.

  ADVANTAGE OF THE INVENTION According to this invention, the ultrasonic diagnostic apparatus which can identify the property characteristic of the structure | tissue inside a biological body only by ultrasonic measurement can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. The ultrasonic diagnostic apparatus 20 of FIG. 1 measures the shape characteristic or the characteristic characteristic of a living body using the ultrasonic probe 1, and is particularly preferably used for measuring the elastic modulus of a living tissue. Here, the shape characteristic of the living body is the shape of the living body tissue, the movement speed of the living body tissue due to the time change of the shape, the movement displacement that is an integral value thereof, the strain change amount between two points set in the living body tissue, etc. Say. The characteristic property of a living body refers to the elastic modulus of a living tissue. The ultrasonic diagnostic apparatus 20 includes a transmission / reception unit 2, a calculation unit 3, a frequency analysis unit 4, a resonance component detection unit 5, a tissue property identification unit 6, a display unit 7, a control unit 104, and a storage unit 105.

  The ultrasonic probe 1 is used for transmitting an ultrasonic wave to a living tissue as a measurement target and receiving an ultrasonic echo obtained by reflecting the transmitted ultrasonic wave on the living tissue. The transmission / reception unit 2 generates a predetermined drive pulse signal for driving the ultrasonic probe 1 and outputs it to the ultrasonic probe 1, and delay-synthesizes the ultrasonic echo received by the ultrasonic probe 1.

  The computing unit 3 computes the movement speed or movement displacement and strain change amount of the living tissue using the signal delayed and synthesized by the transmission / reception unit 2. The frequency analysis unit 4 performs frequency analysis calculations such as the movement speed, movement displacement, strain change coherence, and transfer function obtained by the calculation unit 3.

  Based on the determination result of the frequency analysis unit 4, the resonance component detection unit 5 detects a vibration component due to resonance with respect to the movement speed, movement displacement, and strain change of the living tissue. The tissue property identification unit 6 identifies the biological tissue based on the resonance frequency of the biological tissue detected by the resonance component detection unit 5. The display unit 7 displays the identification result of the biological tissue calculated by the tissue property identification unit 6.

  The control unit 104 controls the transmission / reception unit 2, the calculation unit 3, the frequency analysis unit 4, the resonance component detection unit 5, the tissue property identification unit 6, and the display unit 7. Various types of information for control by the control unit 104 are stored in the storage unit 105.

  When measuring the shape characteristic or property characteristic of an arterial wall, which is an example of a living tissue, using the ultrasonic diagnostic apparatus 20, as shown in FIG. Measure the displacement of the movement and calculate the strain change. FIG. 4 shows points of interest set on the intima and adventitia of the arterial wall, measurement of movement displacement and distortion associated with heartbeat, movement displacement of the arterial wall intima and adventitia, and arteries. A schematic diagram of the wall strain variation is shown.

  Specifically, an ultrasonic wave is transmitted from the ultrasonic probe 1 installed on the biological tissue surface 201 to the artery 202 in the biological tissue, and an ultrasonic echo generated in the artery 202 is received by the ultrasonic probe 1. Is done. These transmitted ultrasonic waves and received ultrasonic waves form an ultrasonic beam 301. When points of interest are set in the intima and adventitia of the arterial wall located on the ultrasound beam 301, the arithmetic unit 3 obtains the difference between the intima movement displacement waveform 401a and the epicardial movement displacement waveform 401b, and the heartbeat The amount of change 402 in the arterial wall strain associated with the change in blood pressure can be obtained.

  FIG. 2 is a block diagram of the calculation unit 3. The calculation unit 3 is connected to the transmission / reception unit 2, the frequency analysis unit 4, and the resonance component detection unit 5, and either the motion speed calculation unit 31 or the movement displacement calculation unit 32 and the strain change amount calculation. A portion 33 is provided.

  The motion speed calculation unit 31 obtains the motion speed of the interest point or the region of interest set in the living tissue using the ultrasonic echo obtained from the living tissue via the transmission / reception unit 2. Any method such as the FFT Doppler method or the autocorrelation method generally used may be used to detect the motion speed of each point of interest or each region of interest in the motion speed calculation unit 31. The movement displacement calculation unit You may obtain | require by differentiating the movement displacement obtained by 32. Since at least two points of interest or regions of interest are set, the spatial distribution of motion speed can be obtained. It is also preferable to simultaneously detect the motion speeds near each interest point or each region of interest and obtain an average value.

  The movement displacement calculation unit 32 obtains the movement displacement of the interest point or the region of interest set in the living tissue by using the ultrasonic echo obtained from the living tissue via the transmission / reception unit 2. Any method such as the FFT Doppler method or the autocorrelation method that is generally used may be used to detect the movement displacement of each point of interest or each region of interest in the movement displacement calculation unit 32. You may obtain | require by integrating the motion speed obtained by 31. FIG. Since at least two points of interest or regions of interest are set, the spatial distribution of movement displacement can be obtained. It is also preferable to simultaneously detect the movement displacement in the vicinity of each interest point or each region of interest and obtain the average value.

  The strain change amount calculation unit 33 integrates at least two or more interest points set on the ultrasonic beam 301 obtained from the motion speed calculation unit 31 or a difference in motion speed of the region of interest, or The distortion change amount is obtained by using the movement displacement of at least two points of interest or the region of interest set on the ultrasonic beam 301 obtained from the movement displacement calculation unit 32. For the calculation of the strain change amount in the strain change amount calculation unit 33, it is also preferable to simultaneously detect the strain change amount in the vicinity of each interest point or each region of interest and obtain the average value. In addition, the spatial distribution may be obtained.

  FIG. 3 is a block diagram of the frequency analysis unit 4. The frequency analysis unit 4 performs frequency analysis calculations such as the movement speed, movement displacement, strain change coherence, and transfer function obtained by the calculation unit 3. And based on the threshold value obtained from the coherence value for a certain period and the attenuation value for each frequency, the vibration component due to the stress change for any or all of the movement speed, the displacement of movement, and the strain change amount, The vibration component due to resonance and the noise component are separated in the frequency domain. The frequency analysis unit 4 includes a coherence calculation unit 41, a transfer function calculation unit 42, a reproducibility evaluation function calculation unit 44, and a frequency separation determination unit 43.

  Hereinafter, the operation of the frequency analysis unit 4 will be described with reference to FIGS. 3 to 6.

  The transfer function calculation unit 42 obtains a transfer function H (k) between the arterial wall intima movement displacement 401a and the arterial wall outer membrane movement displacement 401b. FIG. 6A is an example of the gain characteristic of the transfer function H (k) between the arterial wall intima movement displacement 401a and the arterial wall adventitia movement displacement 401b shown in FIG. This transfer function H (k) can be calculated by (Equation 1) using the cross spectrum method.

  Here, Xi (k) is the frequency spectrum of the input signal, that is, the frequency spectrum of the displacement displacement 401a of the arterial wall, and Yi (k) is the frequency spectrum of the output signal, that is, the spectrum of the displacement displacement 401b of the arterial wall. Further, i represents the i-th cardiac cycle among M cardiac cycles, and i takes a value of 1... I. k is a discrete frequency, * is a complex conjugate, and E is an average operation between cardiac cycles.

  The coherence calculation unit 41 obtains the correlation for each frequency for each cardiac cycle using the amplitude square coherence function. The amplitude square coherence function is a power ratio of components based on the input signal in the output signal, and is expressed by (Expression 2) when the cross spectrum method is used.

  Here, Xi (k) is the frequency spectrum of the input signal, that is, the frequency spectrum of the displacement displacement 401a of the arterial wall, and Yi (k) is the frequency spectrum of the output signal, that is, the spectrum of the displacement displacement 401b of the arterial wall. Further, i represents the i-th cardiac cycle among M cardiac cycles, and i takes a value of 1... I. k is a discrete frequency, * is a complex conjugate, and E is an average operation between cardiac cycles.

  A reproducibility evaluation function may be used instead of the coherence function. The reproducibility evaluation function calculation unit 44 obtains the reproducibility for each frequency for each cardiac cycle using the reproducibility evaluation function. When the cross spectrum method is used, the reproducibility evaluation function is represented by (Expression 3).

  Here, Xi (k) is the frequency spectrum of the input signal, that is, the frequency spectrum of the displacement displacement 401a of the arterial wall, and Yi (k) is the frequency spectrum of the output signal, that is, the spectrum of the displacement displacement 401b of the arterial wall. Further, i represents the i-th cardiac cycle among M cardiac cycles, and i takes a value of 1... I. k is a discrete frequency, * is a complex conjugate, and E is an average operation between cardiac cycles. The reproducibility evaluation function takes a value between 0 and 1, and is close to 1 when the reproducibility between cycles is high.

  The frequency separation determination unit 43 determines a frequency band in which attenuation is equal to or higher than a preset value in a frequency band having high coherence or reproducibility as a frequency band including resonance, and changes the remaining frequency band to a stress change. It is determined that the frequency band of vibration caused by. Therefore, as shown in FIG. 6, the frequency component in frequency band A is due to vibration due to blood pressure change, the frequency component in frequency band B is due to vibration due to resonance, and the frequency component in frequency band C is the frequency band of either A or B. However, it is possible to separate the noise component.

  In the frequency band where coherence or reproducibility is high, the frequency band where the attenuation is less than the preset value is determined as the frequency band of vibration due to stress change, and the remaining frequency band is the frequency band including resonance. You may make it.

  Based on the determination result of the frequency analysis unit 4, the resonance component detection unit 5 detects a vibration component due to resonance for the movement speed, movement displacement, and strain change of the living tissue. The resonance component detection unit 5 includes a filter and can remove signal components other than the resonance component. The constants of the filter are automatically set mainly by the calculation result of the gain characteristic of the transfer function obtained by the frequency analysis unit 4, the amplitude square coherence function, or the reproducibility evaluation function.

  The filter constants may be arbitrarily set by the operator, and it is also preferable to set a plurality of filter constants in advance so that the operator can select them. .

  Further, when the resonance component detection unit 5 performs filter processing on the movement speed, movement displacement, and strain change of the living tissue, the determination result of the frequency analysis unit 4 of the cardiac cycle before the target cardiac cycle is displayed. To determine the filter characteristics. In this way, the method of performing the filtering process on the data of the target cardiac cycle is preferable because the calculation delay time is small and the filtering process time can be shortened.

  Further, the resonance component detection unit 5 performs a filtering process on the movement speed, movement displacement, and strain change of the living tissue in the cardiac cycle using the determination result of the frequency analysis unit 4 of the target cardiac cycle. This method is preferable because optimal filtering can be performed in real time.

  The tissue property identification unit 6 identifies a biological tissue based on the resonance frequency of the biological tissue detected by the resonance component detection unit 5. The elastic model of biological tissue is similar to an electric circuit, the stress f (t) in the elastic model is the voltage v (t) in the electric circuit, and the strain rate u (t) in the elastic model is the current i in the electric circuit. (T) The mass m in the elastic model is similar to the inductance L in the electric circuit, and the elastic modulus μ1 in the elastic model is similar to the capacitance 1 / C in the electric circuit. The resonance frequency f0 in the electric circuit is obtained by (Equation 4).

  When this equation is applied to an elastic model, it is expressed by (Equation 5) from the similarity with an electric circuit.

The mass m of the elastic model corresponding to the inductance L in the electric circuit has a density of approximately 1.1 × 10 ³ kg / m ^{3 in} the case of a living tissue, and therefore, from the resonance frequency f ₀ The elastic modulus μ1 of the elastic model having a capacity 1 / C in the circuit can be obtained. Note that using only the resonant frequency f _0, may be performed to identify the qualitative biological tissue. In the present embodiment, a method for detecting a resonance component for vibration excited by the living body accompanying the heartbeat has been described. However, a broadband vibration is applied from the surface of the living tissue using an exciter or the like. The resonance component of the living tissue may be detected.

  The display unit 7 displays the identification result of the living tissue calculated by the tissue property identification unit 6. The identification result display is preferably displayed at the same time as a B-mode tomographic image which is a display function of a general ultrasonic diagnostic apparatus. In addition, by scanning an ultrasonic beam, a plurality of points of interest or regions of interest are displayed. When the identification result of the biological tissue is required, it is also preferable that the identification result of the biological tissue is color-converted and displayed on the B-mode tomographic image.

  As described above, the tissue itself in the living body can be obtained only by ultrasonic measurement using the frequency characteristics of the living body signal such as the motion speed of the tissue in the living body or the displacement of the living body that is different depending on the subject using the ultrasonic wave. This resonance component can be detected, and the properties of the living tissue can be identified from the resonance component according to the subject.

  The present invention is suitably used for an ultrasonic diagnostic apparatus for measuring a shape characteristic or a characteristic characteristic of a living tissue. In particular, it is suitably used for an ultrasonic diagnostic apparatus capable of diagnosing a living tissue by identifying a living tissue such as an artery.

Block diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention The block diagram which shows the structure of the calculating part of the ultrasound diagnosing device of embodiment of this invention The block diagram which shows the structure of the frequency analysis part of the ultrasonic diagnosing device of embodiment of this invention Schematic diagram showing how the ultrasonic probe receives and transmits ultrasonic waves, measures the displacement of the arterial wall, and calculates the strain change Schematic diagram explaining the effect on strain change when vibration due to resonance is superimposed on the displacement of the arterial wall Schematic diagram showing transfer function gain characteristics, amplitude squared coherence function, and reproducibility evaluation function between arterial intimal displacement and epicardial displacement during one cardiac cycle

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic probe 2 Transmission / reception part 3 Calculation part 4 Frequency analysis part 5 Resonance component separation part 6 Tissue property identification part 7 Display part 31 Movement speed calculation part 32 Movement displacement calculation part 33 Strain change amount calculation part 104 Control part 105 Storage part 201 Biological tissue surface 202 Arterial 301 Ultrasound beam 401a Arterial wall intima movement displacement waveform 401b Arterial wall outer membrane movement displacement waveform 402 Arterial wall distortion change waveform

Claims (9)

An ultrasonic diagnostic apparatus for measuring a shape characteristic or a characteristic characteristic of a biological tissue,
One of a speed calculation unit that calculates the movement speed of the biological tissue, and a movement displacement calculation unit that calculates the movement displacement of the biological tissue,
A strain change amount calculation unit that calculates a strain change amount of the living tissue based on the movement speed or the movement displacement;
A frequency analysis unit that performs frequency analysis on at least one of the movement speed, the movement displacement, and the strain change amount;
Based on the frequency characteristics analyzed by the frequency analysis unit, a resonance component detection unit that detects a vibration component due to resonance of the biological tissue itself with respect to at least one signal among the movement speed, movement displacement, and strain change amount;
Based on the resonance frequency of the biological tissue detected by the resonance component detection unit, a tissue property identification unit that identifies the property of the biological tissue;
An ultrasonic diagnostic apparatus comprising: The ultrasonic diagnostic apparatus according to claim 1,
The speed calculation unit, the movement displacement calculation unit, and the strain change amount calculation unit are configured to calculate the motion speed, the movement displacement, and the strain change amount for a plurality of points of interest or regions of interest set in the living tissue. An ultrasonic diagnostic apparatus having a function for obtaining a spatial distribution. The ultrasonic diagnostic apparatus according to claim 1, wherein:
The speed calculation unit, the movement displacement calculation unit, and the strain change amount calculation unit are ultrasonic diagnostic apparatuses having a function of obtaining a spatial average value of the motion speed, the movement displacement, and the strain change amount. The ultrasonic diagnostic apparatus according to any one of claims 1 to 3,
The frequency analysis unit is an ultrasonic diagnostic apparatus having a function of calculating a frequency spectrum of the movement speed, movement displacement, and strain change amount. The ultrasonic diagnostic apparatus according to any one of claims 1 to 4, wherein
The ultrasonic diagnostic apparatus, wherein the frequency analysis unit has a function of calculating coherence between at least two points of interest of either the movement speed or the movement displacement, and obtains a correlation between fixed periods. The ultrasonic diagnostic apparatus according to any one of claims 1 to 4, wherein
The said frequency analysis part has a function which calculates the reproducibility evaluation function of either the said movement speed or movement displacement, and is an ultrasonic diagnostic apparatus which calculates | requires the reproducibility for every frequency for a fixed period. The ultrasonic diagnostic apparatus according to any one of claims 1 to 4, wherein
The ultrasonic diagnostic apparatus, wherein the frequency analysis unit has a function of calculating a transfer function between at least two points of interest of either the movement speed or the movement displacement, and obtains a gain characteristic for a certain period. The ultrasonic diagnostic apparatus according to any one of claims 1 to 7,
The resonance component detection unit is configured to reproduce at least one of the points of interest of the movement speed and the movement displacement for each frequency of a fixed period, or between a fixed period of at least two points of interest. Based on the coherence and the gain characteristics of the transfer function between at least two points of interest, any one or all of the movement speed, displacement, and strain variation, or all vibration components due to resonance of the living tissue itself An ultrasonic diagnostic apparatus for detecting and identifying a property of the living tissue. The ultrasonic diagnostic apparatus according to any one of claims 1 to 8,
The ultrasonic diagnostic apparatus, wherein the resonance component detection unit includes a band pass filter and / or a band limiting filter, and can remove signal components other than the resonance component.

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