JP4581596B2 - Ultrasonic diagnostic equipment - Google Patents

Description

  The present invention relates to an ultrasonic diagnostic apparatus that detects the motion speed or displacement of an arterial wall tissue in a living body using ultrasound and calculates the thickness change or elastic modulus of the arterial wall tissue.

  As a technique for diagnosing tissue properties of living tissue using ultrasonic waves, a method for obtaining acoustic impedance by transmitting / receiving ultrasonic pulses in the living body (for example, Patent Document 1), displacement when stress is applied to living tissue There is a known method for measuring the strain and obtaining the strain or elastic modulus (for example, Patent Documents 2 and 3).

  Also, as a technique for measuring the motion speed or displacement of a living tissue using ultrasonic waves, for example, an FFT Doppler method using the Doppler effect of an ultrasonic echo signal, or a method using an autocorrelation method is known. (Non-Patent Document 1).

  Spatial resolution in the measurement of in-vivo tissue by ultrasonic waves is divided into azimuth resolution in the surface direction of the ultrasonic probe determined by the beam convergence width of ultrasonic waves and distance resolution that is resolution in the propagation direction of ultrasonic waves.

  The distance resolution in the propagation direction of ultrasonic waves is determined by the center frequency of ultrasonic pulses, the number of ultrasonic pulses, and the propagation speed of ultrasonic waves in the living body. The propagation speed of ultrasonic waves in tissue in the living body is approximately 1540 m / s. Therefore, the distance resolution in the propagation direction of the ultrasonic wave is determined by the center frequency of the ultrasonic pulse and the number of ultrasonic pulses.

  In addition, if the number of ultrasonic pulses transmitted into the living tissue is small, the frequency spectrum distribution of the ultrasonic pulse is widened. Therefore, the spectral intensity of the center frequency of the ultrasonic echo signal reflected by the tissue in the living body is increased. It becomes smaller and the reception sensitivity decreases.

For this reason, in order to increase the reception sensitivity at the center frequency of the ultrasonic echo signal, for example, as shown in Non-Patent Document 1, by increasing the number of ultrasonic pulses transmitted into the living tissue. A technique for narrowing the frequency distribution of the ultrasonic pulse and increasing the spectral intensity of the center frequency of the ultrasonic echo signal reflected by the tissue in the living body has been performed.
JP 2001-170046 A Japanese Patent Laid-Open No. 11-188036 Japanese Patent Laid-Open No. 10-5226 Japan Electronic Machinery Manufacturers Association "Revised Medical Ultrasound Handbook", Corona, January 20, 1997, pp. 116-123

  As the arterial wall in the body changes with the development of atheroma and calcification due to the disease of arteriosclerosis, it is very important to distinguish and identify the tissue characteristics of the arterial wall. Many ultrasonic measurement and diagnosis are also performed.

  The distance resolution in the propagation direction of ultrasonic waves is determined by the center frequency of ultrasonic pulses, the number of ultrasonic pulses, and the propagation speed of ultrasonic waves in the living body. The propagation speed of ultrasonic waves in tissue in the living body is approximately 1540 m / s. Therefore, the distance resolution in the propagation direction of the ultrasonic wave is determined by the center frequency and the number of ultrasonic pulses of the ultrasonic pulse, and the distance when the number of pulses is set to 1 using the ultrasonic wave with the central frequency of 7.5 MHz. The resolution is about 400 μm.

  However, even if the ultrasonic vibrator is excited with the number of pulses set to 1, the ultrasonic vibrator resonates, so that the transmitted ultrasonic wave has a plurality of pulses called tailing accompanied by attenuation of the vibration of the vibrator. appear.

  For example, when measuring the arterial wall, the acoustic impedance of blood and arterial wall tissue differs at the boundary between the arterial lumen and the inner surface of the arterial wall (intima). And a strong echo with a large amplitude, and interferes with a weak echo portion having a small amplitude of reflection from the inner surface to the outer surface of the artery wall.

  Therefore, when trying to measure the distortion of the arterial wall, it seems that distortion does not occur due to the influence of the strong echo part in the weak echo part where there is a strong echo in the vicinity. It is necessary to set a point, and there is a problem that distance resolution is lowered.

  However, in an arterial wall tissue where only weak echoes without strong echoes are distributed, if it is possible to distinguish each of a plurality of weak echoes distributed, a measurement point is set for each weak echo. The strain can be measured.

  The present invention has been made to solve such a problem, and in the case of measuring strain of a living tissue such as an arterial wall tissue where strong and weak echoes exist, the intensity of the ultrasonic echo signal is increased. Accordingly, an object of the present invention is to enable distortion measurement without error with optimum distance resolution by setting a distance between a plurality of measurement points for measuring distortion.

  The ultrasonic diagnostic apparatus of the present invention stores an ultrasonic probe configured by a group of ultrasonic transducers, a transmission signal generating unit, a transmission / reception signal delay control unit of each ultrasonic transducer, and the delay control amount. A delay control amount storage means; a reception signal synthesis means for synthesizing a reception signal from each ultrasonic transducer group; a detection means for detecting the synthesized reception signal; and a living body from the detected ultrasonic echo detection signal. And a signal processing means for determining the amount of distortion of the arterial wall in the living body from the movement speed.

  With this configuration, it is possible to transmit ultrasonic waves into the living body and detect the motion speed, movement displacement amount, and distortion amount of the arterial wall in the living body from the ultrasonic echo signals obtained from the living body.

  Further, the detection unit has a function of storing a table of waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception, and a function to compare with the ultrasonic echo detection signal Is provided.

  With this configuration, the actually measured ultrasonic echo signal can be compared with the one reflected from the biological tissue by the tailing of the ultrasonic transducer, and according to the ultrasonic transmission / reception center frequency. By making the waveform information into a table, the signals can be compared with respect to various ultrasonic probes having the center frequency.

  Further, the detection unit has a function of calculating waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception, and has a function of comparing with the ultrasonic echo detection signal. .

  With this configuration, the actually measured ultrasonic echo signal can be compared with the one reflected from the biological tissue by the tailing of the ultrasonic transducer, and according to the ultrasonic transmission / reception center frequency. By calculating the waveform information, the signals can be compared for ultrasonic probes having various center frequencies or biological tissues having various attenuation characteristics.

  In addition, the signal processing unit has a plurality of measurement point intervals for calculating the elastic modulus based on a comparison result of the waveform information based on the propagation attenuation characteristic in the living tissue in the detection unit and the ultrasonic echo detection signal. A function to set the setting arbitrarily is provided.

  With this configuration, when measuring strain in living tissue such as arterial wall tissue where strong and weak echoes exist, the distance between multiple measurement points for measuring strain according to the intensity of the ultrasonic echo signal By performing the above setting, it is possible to perform distortion measurement without error with optimum distance resolution.

  The present invention relates to an ultrasonic probe comprising a group of ultrasonic transducers, a transmission signal generating unit, a delay control unit for transmission / reception signals of each ultrasonic transducer, and a delay control amount storage unit for storing the delay control amount. Receiving signal synthesizing means for synthesizing the received signals from each ultrasonic transducer group, detecting means for detecting the synthesized received signals, and detection of the arterial wall tissue in the living body from the detected ultrasonic echo detection signals. An ultrasonic diagnostic apparatus comprising: a motion speed detection means for detecting a motion speed and a movement displacement amount; and a signal processing means for obtaining a distortion amount of an arterial wall in a living body from the motion speed, wherein the detection means However, based on the comparison result of the waveform information based on the propagation attenuation characteristics in the living tissue and the ultrasonic echo detection signal, the setting of the multiple measurement point intervals for calculating the elastic modulus is arbitrarily set. Echo and weak eco When measuring strains of living tissue such as arterial wall tissue where there is a noise, it is optimal to set the distance between multiple measurement points to measure the strain according to the intensity of the ultrasonic echo signal. Distortion measurement without error can be performed with distance resolution.

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

(First embodiment)
FIG. 1 is a block diagram showing a configuration of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. 1 is an ultrasonic transducer group, 2 is an ultrasonic probe, 3 is a delay control unit, and 4 is a delay control amount storage. , 5 is a transmission signal generation unit, 6 is a reception signal synthesis unit, 7 is a reception signal storage unit, 8 is a detection unit, 9 is a motion speed detection unit, 10 is a signal processing calculation unit, 11 is a display unit, and 12 is a control unit. , 13 is a storage unit, and 31 is a biological signal detection unit.

  The ultrasonic transmission signal generated by the transmission signal generation unit 5 is delayed by the delay control unit 3 for each transducer of the ultrasonic transducer group 1, and passes through the ultrasonic transducer group 1 of the ultrasonic probe 2. And transmitted to the living body.

  The ultrasonic echo reflected by the tissue in the living body is received by each transducer of the ultrasonic transducer group 1 of the ultrasonic probe 2, subjected to delay control by the delay control unit 3, and then received by the reception signal synthesis unit 6. Synthesized into an ultrasonic echo signal.

  The detection unit 8 detects the ultrasonic echo signal synthesized by the reception signal synthesis unit 6.

  The detection unit 8 has a function of storing a table of waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception, and an ultrasonic echo obtained by detection The detection signal is compared with preset waveform information.

  Furthermore, the detection unit 8 has a function of calculating waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception, and an ultrasonic echo detection signal obtained by detection And the previously calculated waveform information are compared.

  The detection method in the detection unit 8 may be any method such as envelope detection or quadrature detection.

  The motion speed detector 9 detects the motion speed and displacement of the tissue in the living body that is the measurement target from the ultrasonic echo detection signal detected by the detector 8.

  The movement speed of each measurement point in the living body can be detected by any of the commonly used methods such as FFT Doppler method and autocorrelation method. In addition, the motion speed of a plurality of measurement points in the living body may be detected.

  The motion speed detector 9 can set a plurality of measurement points in one ultrasonic echo signal and simultaneously detect the motion speeds or movement displacements of the plurality of measurement points.

  In the signal processing calculation unit 10, it is possible to obtain the amount of distortion from the movement speed and movement displacement of the arterial wall in the living body at a plurality of measurement points detected by the movement speed detection unit 8.

  Further, it is possible to obtain the elastic modulus from the amount of distortion of the arterial wall using the blood pressure value detected by the biological signal detection unit 31 or a preset blood pressure value.

  The display unit 11 displays the motion speed and displacement of the in-vivo arterial wall detected by the motion speed detection unit 8, and the strain amount and elastic modulus of the in-vivo artery wall obtained by the signal processing calculation unit.

  The motion speed, displacement, strain, and elastic modulus of the arterial wall in the living body may be displayed superimposed on a B-mode tomographic image that is a basic function of a general ultrasonic diagnostic apparatus.

  The control unit 12 controls the delay control unit 3, the transmission signal generation unit 5, the reception signal synthesis unit 6, the motion speed detection unit 8, the signal processing calculation unit 9, and the display unit 10, and the delay control unit 3, Information obtained by the transmission signal generation unit 5, the reception signal synthesis unit 6, the motion speed detection unit 8, the signal processing calculation unit 9 and the display unit 11 and the control information are stored in the storage unit 13.

  FIG. 2 shows an example of measuring the motion speed, displacement, and strain of a living artery wall.

  As shown in one embodiment of FIG. 2, a plurality of measurement points are set on the intima side and the adventitia side of the arterial wall on one ultrasonic beam, and at the same time, the motion speed or displacement of the plurality of measurement points is set. To detect.

  In this embodiment, the measurement points are set on the intima side and the adventitia side of the artery wall, but a plurality of measurement points may be set from the intima side to the adventitia side.

  Further, as shown in one embodiment of FIG. 2, it is possible to spatially measure the arterial wall motion speed, displacement, and strain by scanning an ultrasonic beam.

(Second Embodiment)
FIG. 3 shows a waveform based on the ultrasonic echo detection signal detected by the detection unit 8 and the propagation attenuation characteristic in the living tissue for each pulse number when there is a weak echo reflector in the vicinity of the strong echo reflector. It is one Example which compares information.

  The detection unit 8 has a function of storing a table of waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception, and an ultrasonic echo detection signal obtained by detection And the preset waveform information can be compared, and the waveform information can be compared using the amplitude value of the waveform or the cross-correlation method.

  As shown in FIG. 3, the ultrasonic wave transmitted from the ultrasonic probe 2 is reflected at the boundary surface A and the boundary surface B, and the ultrasonic echo signal is transmitted at the boundary surface A corresponding to the propagation distance from the ultrasonic probe. And the reflection on the boundary surface B are detected as one time signal having a time difference.

  The ultrasonic waves reflected by the boundary surface A and the boundary surface B appear as peaks in the ultrasonic echo signal. When there are two boundary surfaces A and B as shown in FIG. appear.

  The amplitude of the peak of the ultrasonic echo signal changes depending on the difference in acoustic impedance between the two media constituting the boundary surface.

  The detector 8 has a function of detecting the peak of the ultrasonic echo signal reflected at the boundary surface, like the ultrasonic echo signal shown in FIG.

  As an example of peak detection, an ultrasonic echo signal can be easily detected by detecting an envelope and detecting an inflection point of the obtained envelope.

  In this embodiment, the waveform used for peak detection is obtained by envelope detection of an ultrasonic echo signal. However, an amplitude waveform obtained from a signal obtained by orthogonal detection of the ultrasonic echo signal may be used.

  The detector 8 also has a function of storing a table of waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception.

  Waveform information is the theoretical value of the detection signal based on the propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasound transmission / reception. A plurality of waveform information is tabulated according to the conditions of ultrasound transmission / reception. Prepared.

  Further, the detection unit 8 compares the tabulated waveform information with the ultrasonic echo detection signal obtained by the detection.

  The comparison is performed by comparing the amplitude of the ultrasonic echo detection signal obtained by detection with respect to the theoretical value of the propagation attenuation characteristic in the living tissue for each center frequency and number of pulses of the tabulated ultrasonic transmission / reception. This is done by detecting the difference between amplitude and phase.

  As an example of the comparison, a cross-correlation between the theoretical value of the propagation attenuation characteristic in the living tissue for each center frequency and number of pulses of the ultrasonic transmission / reception and the ultrasonic echo detection signal obtained by the detection is taken. The correlation window width may be fixed, but may be arbitrarily set based on the half-value width of the maximum amplitude of the theoretical value, for example.

  In this embodiment, the theoretical value was compared with the ultrasonic detection signal by taking the cross-correlation, but the theoretical value was compared with the peak amplitude value of the detected ultrasonic echo detection signal. You can do it.

(Third embodiment)
The detection unit 8 has a function of calculating waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception, and an ultrasonic echo detection signal obtained by detection. And the previously calculated waveform information can be compared, and the waveform information can be compared using the amplitude value of the waveform or the cross-correlation method.

  The waveform information is obtained from the transmission signal waveform of the ultrasonic probe 2 and the attenuation characteristics of the ultrasonic wave in the living tissue.

  Here, it is generally known that the transmission signal waveform of the ultrasonic probe 2 can be approximated by a Gaussian function, and the transmission signal waveform has the propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception. It is obtained by multiplying the result of calculating the waveform information based on it.

  The attenuation rate of ultrasonic waves in living tissue is expressed in units of dB / cm / MHz, and has a frequency dependence. The attenuation rate of general living tissue is 0.5 to 0.7 dB / cm / MHz.

Using this attenuation factor, when attenuation is expressed as a system function H (d, f),
H (d, f) = exp (-2αdf)
The relational expression between the signal Y (d, f) received by the probe and the transmission signal X (d, f) is
Y (d, f) = H (d, f) X (d, f)
Can be expressed as

  Here, a is the attenuation factor, d is the position of the reflection source, and f is the frequency.

  The detection unit 8 calculates the attenuation characteristic of each frequency based on the frequency spectrum distribution that changes depending on the number of pulses of ultrasonic transmission, and obtains the propagation attenuation characteristic in the living tissue according to the number of pulses of ultrasonic transmission.

  In the present embodiment, the method of calculating the attenuation characteristic of each frequency based on the frequency spectrum distribution of the ultrasonic transmission signal is shown. However, when the frequency spectrum distribution is narrow, only the center frequency of the ultrasonic transmission signal is shown. Only the attenuation characteristic may be calculated.

  In the present embodiment, a method of approximating an ultrasonic transmission signal with a Gaussian function is shown. However, an ultrasonic transmission signal actually measured with a hydrophone or the like may be stored as a table.

  Further, as in the second embodiment, the detection unit 8 compares the calculated waveform information with the ultrasonic echo detection signal obtained by detection.

  The comparison is performed by comparing the amplitude of the ultrasonic echo detection signal obtained by detection with respect to the theoretical value of the propagation attenuation characteristic in the living tissue for each center frequency and number of pulses of the tabulated ultrasonic transmission / reception. This is done by detecting the difference between amplitude and phase.

  As an example of the comparison, a cross-correlation between the theoretical value of the propagation attenuation characteristic in the living tissue for each center frequency and number of pulses of the ultrasonic transmission / reception and the ultrasonic echo detection signal obtained by the detection is taken. The correlation window width may be fixed, but may be arbitrarily set based on the half-value width of the maximum amplitude of the theoretical value, for example.

  In this embodiment, the theoretical value was compared with the ultrasonic detection signal by taking the cross-correlation, but the theoretical value was compared with the peak amplitude value of the detected ultrasonic echo detection signal. You can do it.

(Fourth embodiment)
The signal processing calculation unit 10 of the ultrasonic diagnostic apparatus according to the embodiment of the present invention is based on the comparison result between the waveform information based on the propagation attenuation characteristic in the living tissue in the detection unit 9 and the ultrasonic echo detection signal. It is possible to arbitrarily set a plurality of measurement point intervals for calculating the rate.

  FIG. 4 shows a schematic diagram of an anatomical structure of an arterial long-axis section and an ultrasonic tomogram.

  As shown in FIG. 4, the anatomical structure of the arterial wall is a three-layer structure of the intima, media and adventitia from the lumen side of the artery. The far side is called the rear wall.

  When an artery having such a three-layer structure is measured with ultrasound, the ultrasound is reflected at the boundary portion where the acoustic impedance is different, so that the boundary between the arterial side and the blood in the arterial lumen, the arterial outer membrane, Reflection occurs at the boundary of the surrounding tissue, the boundary between the media and the outer membrane, and the ultrasonic tomogram is as shown in the schematic diagram of FIG.

  However, the reflection intensity of the ultrasonic wave at the boundary surface varies greatly depending on the difference in acoustic impedance at each boundary surface. For example, reflection from the boundary surface between the blood in the artery lumen and the intima becomes a strong echo. On the other hand, the reflection intensity at the boundary surface between the inner membrane and the inner membrane is a very small weak echo.

  Furthermore, as described above, the width of the reflected wave is widened due to the number of transmitted ultrasonic pulses and tailing, resulting in a decrease in distance resolution, and the weak echo reflector is located in the vicinity of the strong echo reflector. In this case, the weak echo is buried in the strong echo, making it difficult to separate.

  In order to measure strain on the arterial wall, it is necessary to set multiple measurement points, track each set measurement point, and obtain the difference in motion speed or movement displacement of the multiple measurement points set at the same time If a plurality of measurement points are set in the same strong echo portion, distortion cannot be obtained.

  FIG. 5 and FIG. 6 are schematic diagrams of measurement point setting based on a comparison result between waveform information based on distance attenuation characteristics in a living tissue and an ultrasonic echo detection signal.

  In FIG. 5, boundary A is a boundary surface that reflects strong echoes and boundary B is a boundary surface that reflects weak echoes.

  When an ultrasonic wave is incident from the ultrasonic probe 2 from the boundary A side, the tail of the strong echo generated at the boundary A extends to a position exceeding the weak echo portion generated at the boundary B side. If the reflected echo intensity is smaller than the reflected echo intensity generated at the boundary A where the distance is attenuated, the reflected echo from the boundary B cannot be identified.

  On the other hand, in FIG. 6, both the boundary A and the boundary B are boundary surfaces that reflect the same echo intensity.

  When an ultrasonic wave enters from the boundary A side from the ultrasonic probe 2, the tail of the strong echo generated at the boundary A extends to a position exceeding the weak echo portion generated at the boundary B side. When the reflected echo intensity from the boundary B is larger than the reflected echo intensity generated at the boundary A where the distance is attenuated, the reflected echo from the boundary B can be identified.

  The signal processing calculation unit 10 has a plurality of measurement point intervals for calculating the elastic modulus based on the comparison result of the waveform information based on the propagation attenuation characteristic in the living tissue in the detection unit 9 and the ultrasonic echo detection signal. The setting can be arbitrarily set.

  With this configuration, when measuring strain in living tissue such as arterial wall tissue where strong and weak echoes exist, the distance between multiple measurement points for measuring strain according to the intensity of the ultrasonic echo signal By performing the above setting, it is possible to perform distortion measurement without error with optimum distance resolution.

  The present invention relates to an ultrasonic probe comprising a group of ultrasonic transducers, a transmission signal generating unit, a delay control unit for transmission / reception signals of each ultrasonic transducer, and a delay control amount storage unit for storing the delay control amount. Receiving signal synthesizing means for synthesizing the received signals from each ultrasonic transducer group, detecting means for detecting the synthesized received signals, and detection of the arterial wall tissue in the living body from the detected ultrasonic echo detection signals. An ultrasonic diagnostic apparatus comprising: a motion speed detection means for detecting a motion speed and a movement displacement amount; and a signal processing means for obtaining a distortion amount of an arterial wall in a living body from the motion speed, wherein the detection means However, based on the comparison result of the waveform information based on the propagation attenuation characteristics in the living tissue and the ultrasonic echo detection signal, the setting of the multiple measurement point intervals for calculating the elastic modulus is arbitrarily set. Echo and weak eco When measuring strains of living tissue such as arterial wall tissue where there is a noise, it is optimal to set the distance between multiple measurement points to measure the strain according to the intensity of the ultrasonic echo signal. Strain measurement without error can be performed with distance resolution, and the amount of strain is obtained from the movement speed and displacement of the arterial wall in the living body measured at multiple measurement points, and further detected by the biological signal detection means This is useful for an ultrasonic diagnostic apparatus or the like that obtains the strain amount and elastic modulus of an arterial wall in a living body using the blood pressure value set in advance or the blood pressure value set in advance.

1 is a schematic block diagram of an ultrasonic diagnostic apparatus according to a first embodiment of the present invention. The schematic diagram which showed the measurement of the movement speed of the arterial wall in the 1st Embodiment of this invention, a movement displacement, and distortion amount Waveform information based on detected ultrasonic echo signals and propagation attenuation characteristics in living tissue when a weak echo reflector is in the vicinity of a strong echo reflector in the second and third embodiments of the present invention Schematic showing one example of comparing Schematic diagram of anatomical structure and ultrasonic tomographic image of arterial long-axis section in the fourth embodiment of the present invention The schematic diagram of the measurement point setting based on the comparison result of the waveform information based on the distance attenuation | damping characteristic in the biological tissue and the ultrasonic echo detection signal in the 4th Embodiment of this invention The schematic diagram of the measurement point setting based on the comparison result of the waveform information based on the distance attenuation | damping characteristic in the biological tissue and the ultrasonic echo detection signal in the 4th Embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic transducer group 2 Ultrasonic probe 3 Delay control part 4 Delay control amount memory | storage part 5 Transmission signal generation part 6 Received signal synthetic | combination part 7 Received signal memory | storage part 8 Detection part 9 Motion speed detection part 10 Signal processing calculating part 11 Display Unit 12 Control unit 13 Storage unit 31 Biosignal detection unit

Claims (4)

In an ultrasonic diagnostic apparatus that displays a tomographic image in a living tissue, an ultrasonic probe configured by an ultrasonic transducer group that transmits and receives ultrasonic waves to and from an arterial wall tissue in the living body, and each ultrasonic transducer group A delay control unit that performs delay control of the ultrasonic transducer, a delay control amount storage unit that stores a delay control amount of each of the ultrasonic transducers, and any ultrasonic echo signal received by the ultrasonic transducer group A reception signal synthesizer that selects and synthesizes an ultrasonic echo signal of an ultrasonic transducer; and an ultrasonic echo detection signal obtained by detecting the ultrasonic echo signal synthesized by the reception signal synthesizer; a detection unit for comparing the waveform information based on the propagation attenuation characteristics of the detection signal and the living tissue, and pre-Symbol movement speed detection means for detecting a movement speed or the displacement of the arterial wall tissue from the ultrasound echo detection signal, the From the difference of the arterial wall tissue motion velocity or the displacement of the measurement point of the two points that are arbitrarily selected from a plurality of measurement points set in the membrane wall, the thickness variation of the arterial wall, the signal processing to calculate the elastic modulus Computing means and display means for displaying the computation results obtained by the signal processing computing means, the signal processing computing means from the plurality of measurement points based on the comparison results of the detection unit An ultrasonic diagnostic apparatus having a function of arbitrarily selecting two measurement points having different echo signal intensities . The detection unit has a function of storing a table of waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception, and has a function of comparing with the ultrasonic echo detection signal. The ultrasonic diagnostic apparatus according to claim 1. The detection unit had a function of calculating waveform information based on propagation attenuation characteristics in the living tissue for each center frequency and number of pulses of ultrasonic transmission / reception, and had a function of comparing with the ultrasonic echo detection signal The ultrasonic diagnostic apparatus according to claim 1. 4. The comparison according to claim 1, wherein the comparison is performed by detecting an amplitude or a difference in amplitude and phase between the ultrasonic echo detection signal and waveform information based on propagation attenuation characteristics in the living tissue. Ultrasonic diagnostic equipment.

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