JP5388416B2 - Ultrasonic diagnostic apparatus and control program for ultrasonic diagnostic apparatus - Google Patents

Description

  The present invention relates to an ultrasonic diagnostic apparatus that obtains biological information in a subject by irradiating an ultrasonic pulse in the subject, receiving ultrasonic echoes generated in the subject, and performing various processes. The present invention relates to an ultrasonic diagnostic apparatus capable of performing imaging by a contrast echo method using a contrast agent, and a control program for the ultrasonic diagnostic apparatus.

  The ultrasonic diagnostic apparatus irradiates an ultrasonic pulse into the subject from a piezoelectric vibrator (ultrasonic vibrator) built in the ultrasonic probe, and receives the ultrasonic echo generated in the subject with the piezoelectric vibrator. This is a device that obtains biological information such as tomographic images and blood flow images of biological tissue in a subject by performing various processes.

One imaging method using this ultrasonic diagnostic apparatus is an imaging method called a contrast echo method. The contrast echo method is intended to enhance ultrasonic scattering echoes by administering microbubbles as a contrast agent into a blood vessel of a subject. In imaging by the contrast echo method, an ultrasonic pulse having a predetermined frequency spectrum is irradiated, and a nonlinear component of an ultrasonic echo obtained from a microbubble that is a contrast agent is used for imaging (for example, see Patent Document 1). .
JP-A-8-182680

  However, in the imaging technique in the conventional contrast echo method, only a part of the bubble administered into the subject contributes to the imaging. This is due to the fact that the signal intensity of the nonlinear component included in the ultrasonic echo strongly depends on the bubble radius when the frequency of the ultrasonic pulse to be irradiated is constant. In other words, since the resonance frequency of the bubble varies depending on the radius, only some of the bubbles administered into the subject have a radius that resonates with the frequency of the transmitted ultrasonic pulse can be used for imaging. Absent.

  For this reason, it is desired from the viewpoint of sensitivity to acquire and visualize ultrasonic echoes from bubbles of different radii.

  On the other hand, there is a problem that bubbles are destroyed by transmitted ultrasonic pulses. For this reason, in imaging using the contrast echo method, an ultrasonic pulse having an amplitude of only about 1/10 that of an ultrasonic pulse normally used in non-contrast imaging is used for imaging. Therefore, there is a problem that sensitivity may be insufficient particularly in a deep part. In particular, in Low MI (mechanical index) mode imaging using a low sound pressure ultrasonic pulse that does not break a bubble, the sensitivity is actually insufficient.

  In addition, a technique has been devised in which a second harmonic (second harmonic) component is used for imaging as a nonlinear component included in an ultrasonic echo from a bubble. However, with this technique, tissue harmonic components from living tissue are also imaged, and there is a problem that it is difficult to see blood flow shadows due to bubbles.

  The present invention has been made to cope with such a conventional situation, and provides an ultrasonic diagnostic apparatus capable of easily recognizing a shadowed image with higher sensitivity and a control program for the ultrasonic diagnostic apparatus. For the purpose.

  It is another object of the present invention to provide an ultrasonic diagnostic apparatus and a control program for the ultrasonic diagnostic apparatus that can reduce the motion artifact of the ultrasonic image. And

  Furthermore, the present invention has been made to cope with such a conventional situation, and an ultrasonic diagnostic apparatus and an ultrasonic diagnostic apparatus control program capable of increasing the signal intensity of a bubble echo while reducing the signal intensity of a tissue echo. The purpose is to provide.

  In addition, the present invention has been made in order to cope with such a conventional situation, and provides an ultrasonic diagnostic apparatus and a control program for the ultrasonic diagnostic apparatus that can thin vertical stripes appearing on an ultrasonic image. For the purpose.

Ultrasonic diagnostic apparatus according to the present invention, in order to solve the above problems, as described in claim 1, the plurality of ultrasonic pulse center frequencies different from each other is transmitted to the object by the ultrasonic probe A first received echo acquisition means for acquiring each received echo received in step (b), and transmitting an ultrasonic pulse having the same frequency component characteristics as the synthesized pulse obtained by synthesizing the plurality of ultrasonic pulses to the subject. A second received echo acquisition means for acquiring the received echo, and a combination of the received echo acquired by the first received echo acquisition means and the received echo acquired by the second received echo acquisition means Receiving echo synthesis means for generating a signal; and image generation means for generating an image of an echo from the subject from the synthesized signal.

In order to solve the above-described problem, a control program for an ultrasonic diagnostic apparatus according to the present invention includes: a computer included in an ultrasonic diagnostic apparatus that includes a plurality of ultrasonic waves having different center frequencies; first received echo acquiring means for acquiring the received echoes of the received ultrasound probe Taso respectively from the ultrasonic probe by a pulse is transmitted from the ultrasonic probe to the subject, the plurality of ultrasonic An ultrasonic pulse having the same frequency component characteristics as the synthesized pulse obtained by synthesizing the pulse is transmitted from the ultrasonic probe to the subject, and a reception echo received by the ultrasonic probe is acquired from the ultrasonic probe . Second received echo acquisition means, received echo acquired by the first received echo acquisition means and second received echo acquisition Receiving echoes synthesizing means for generating a combined signal by combining the received echoes obtained by means and image generating means for generating an echo image from the subject from the composite signal, to function as a.

  In the ultrasonic diagnostic apparatus and the control program for the ultrasonic diagnostic apparatus according to the present invention, it is possible to easily recognize the shadowing due to bubbles with higher sensitivity.

  Further, in the ultrasonic diagnostic apparatus and the control program for the ultrasonic diagnostic apparatus according to the present invention, motion artifacts of the ultrasonic image can be reduced.

  Furthermore, in the ultrasonic diagnostic apparatus and the control program for the ultrasonic diagnostic apparatus according to the present invention, the signal intensity of the bubble echo can be increased while the signal intensity of the tissue echo can be reduced.

  In addition, in the ultrasonic diagnostic apparatus and the control program for the ultrasonic diagnostic apparatus according to the present invention, vertical stripes appearing on the ultrasonic image can be reduced.

  Embodiments of an ultrasonic diagnostic apparatus and a control program for the ultrasonic diagnostic apparatus according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a configuration diagram showing a first embodiment of an ultrasonic diagnostic apparatus according to the present invention.

  The ultrasonic diagnostic apparatus 1 according to the first embodiment is configured by providing an ultrasonic probe 3 and a monitor 4 in an apparatus main body 2. The apparatus main body 2 includes a transmission / reception unit 5, an A / D (analog to digital) converter 6, a signal processing unit 7, a detection unit 8, a scan sequence control unit 9, a system control unit 10, and a display unit 11. Each component of the apparatus main body 2 can be constructed by a circuit or by reading a control program into a CPU (central processing unit) of a computer.

  The ultrasonic probe 3 includes a plurality of ultrasonic transducers. Each ultrasonic transducer converts a transmission signal applied as an electric pulse from the transmission / reception unit 5 into an ultrasonic pulse and transmits the ultrasonic pulse into a subject (not shown). On the other hand, each ultrasonic transducer is generated by the ultrasonic pulse transmitted inside the subject It has a function of receiving an ultrasonic echo and giving it to the transmission / reception unit 5 as a reception echo which is an electric signal.

  The transmission / reception unit 5 applies a transmission signal to each ultrasonic transducer of the ultrasonic probe 3 in accordance with a control signal given as a scan sequence from the scan sequence control unit 9, so that the ultrasonic probe 3 has a predetermined characteristic. It has a function of controlling the ultrasonic probe 3 so that a sound wave pulse is transmitted. Further, it has a function of receiving the received echo from the ultrasonic probe 3 and performing predetermined pre-processing such as delay processing and phasing addition processing, and thereafter giving it to the A / D converter 6.

  The scan sequence control unit 9 provides the transmission / reception unit 5 with a control signal as a scan sequence so that an ultrasonic pulse corresponding to a predetermined frequency spectrum (frequency component) is transmitted from the ultrasonic probe 3. It has a function to control. Specifically, the scan sequence control unit 9 sequentially transmits a plurality of ultrasonic pulses corresponding to a plurality of frequency spectra in which at least one of the center frequency, amplitude, and frequency band is different from the ultrasonic probe 3. The transmitter / receiver 5 has a function of giving a control signal to control. In addition, when the plurality of ultrasonic pulses are sequentially transmitted, the scan sequence control unit 9 can sequentially transmit at least one of the phase, the transmission aperture, and the transmission focal point for each of the plurality of ultrasonic pulses.

  In particular, the scan sequence control unit 9 sequentially transmits a plurality of ultrasonic pulses having different frequency spectra and ultrasonic pulses reflecting the same frequency component characteristics as the ultrasonic pulse synthesized by linearly calculating them. Is configured to set a scan sequence.

  The A / D converter 6 has a function of converting the analog reception echo received from the transmission / reception unit 5 into a digital reception echo and providing the digital reception echo to the signal processing unit 7 or the detection unit 8.

  The signal processing unit 7 has a function of performing signal processing on the received echo received from the A / D converter 6 and a function of giving the combined signal obtained by the signal processing to the detection unit 8. Specifically, the signal processing unit 7 is configured to perform signal processing for synthesizing received echoes corresponding to ultrasonic pulses having different frequency spectra and generating a synthesized signal.

  The detection unit 8 acquires a necessary pulse signal or reception echo from the signal processing unit 7 or the A / D converter 6, performs envelope detection of the acquired pulse signal or reception echo, and displays the detection result as a detection signal. It has a function to give to. In particular, the detection unit 8 obtains a pulse signal from the signal processing unit 7 for a contrast image using microbubbles by contrast echo method and generates a detection signal, while the tissue (B -Mode) It is configured to acquire a predetermined reception echo from the A / D converter 6 for an image and generate a detection signal.

  Note that the arrangement of the signal processing unit 7 and the detection unit 8 may be reversed. In that case, the detection unit 8 acquires a necessary reception echo from the A / D converter 6 and performs envelope detection of the acquired reception echo. In addition, the signal processing unit 7 performs signal processing on the received echo received from the detection unit 8.

  The display unit 11 includes a DSC (digital scan converter). The display unit 11 has a function of generating a video signal for monitor display from the detection signal received from the detection unit 8 and providing the generated video signal to the monitor 4 for display. The display unit 11 is configured to convert the detection signal received from the detection unit 8 by the DSC from a scanning method of ultrasonic scanning to a television scanning method for display.

  The system control unit 10 performs overall control by giving control signals to the transmission / reception unit 5, the A / D converter 6, the signal processing unit 7, the detection unit 8, and the scan sequence control unit 9, which are each component in the apparatus main body 2. It has a function.

  Next, the operation of the ultrasonic diagnostic apparatus 1 will be described.

  FIG. 2 is a flowchart showing a procedure for imaging blood flow by contrast echo method using microbubbles as a contrast agent by the ultrasonic diagnostic apparatus 1 shown in FIG. Reference numeral indicates each step of the flowchart.

  First, a contrast medium composed of microbubbles is administered to a subject in advance. A large number of microbubbles having various radii are introduced into a region to be imaged such as a blood vessel.

  In step S1, for example, ultrasonic pulses p1 and p2 having different center frequencies f1 and f2 are transmitted from the ultrasonic probe 3 to the imaging target site in the subject at different timings. Then, ultrasonic echoes generated by the microbubbles in the imaging target region are received by the ultrasonic probe 3 and acquired by the signal processing unit 7 as reception echoes E1 and E2.

  That is, the scan sequence control unit 9 generates a scan sequence so that the ultrasonic pulse p1 having the center frequency f1 and the ultrasonic pulse p2 having the center frequency f2 are sequentially transmitted from the ultrasonic probe 3 at regular intervals. However, the center frequency f2 is set to a value different from the center frequency f1.

  The scan sequence control unit 9 gives the generated scan sequence to the transmission / reception unit 5. Then, the transmission / reception unit 5 generates a transmission signal according to the scan sequence received from the scan sequence control unit 9 and gives the generated transmission signal to each ultrasonic transducer of the ultrasonic probe 3. For this reason, the ultrasonic probe 3 transmits an ultrasonic pulse p1 having a center frequency f1 and an ultrasonic pulse p2 having a center frequency f2 (f2 ≠ f1) to the imaging target site in the subject.

  Since there are many microbubbles having different radii in the imaging target region, the ultrasound probe 3 is received by the ultrasound probe 3 as a result of the ultrasound pulse being reflected on the microbubble or tissue. The ultrasonic echoes received by the ultrasonic probe 3 and corresponding to the two ultrasonic pulses p1 and p2 are converted into reception echoes E1 and E2 which are electric signals and sequentially given to the transmission / reception unit 5.

  The transmission / reception unit 5 sequentially provides the reception echoes E 1 and E 2 received from the ultrasonic probe 3 to the A / D converter 6. The A / D converter 6 converts the analog reception echoes E1 and E2 given from the transmission / reception unit 5 into digital reception echoes E1 and E2, respectively. The digitized reception echoes E1 and E2 are sequentially supplied from the A / D converter 6 to the signal processing unit 7.

  The signal processing unit 7 performs predetermined processing such as delay processing and phasing addition processing on the reception echoes E1 and E2 received from the A / D converter 6. The signal processing unit 7 temporarily stores reception echoes E1 and E2 corresponding to the two types of transmission ultrasonic pulses p1 and p2, respectively.

  FIG. 3 is a schematic diagram illustrating an example of a frequency spectrum corresponding to a plurality of ultrasonic pulses sequentially transmitted from the ultrasonic probe 3 of the ultrasonic diagnostic apparatus 1 illustrated in FIG. 1, and FIG. 4 is illustrated in FIG. It is a schematic diagram which shows an example of the frequency spectrum of the reception echo from the bubble each obtained by transmission of each ultrasonic pulse.

  The horizontal axis in FIGS. 3 and 4 indicates the frequency. As shown in FIG. 3, an ultrasonic pulse p1 having an ultrasonic spectrum with a center frequency f1 and an ultrasonic pulse p2 having an ultrasonic spectrum with a center frequency f2 are directed from the ultrasonic probe 3 to the microbubbles in the subject. Are sent sequentially.

  Then, the radii of the microbubbles existing in the imaging target region are distributed in different values, but include the fundamental wave band from the microbubbles having radii that resonate corresponding to each frequency spectrum of the transmitted ultrasonic pulse. A nonlinear signal component can be obtained in a wide area. In other words, by setting each center frequency of each transmitted ultrasonic pulse to a different value and shifting each frequency spectrum, it is nonlinear from microbubbles with more radii in a wide area including the fundamental band. Ingredients can be obtained.

  For this reason, bubble echoes Eb1 and Eb2, which are nonlinear components obtained from the microbubbles in the received echoes E1 and E2, respectively, have frequency spectra of mutually different center frequencies f1 and f2, as shown in FIG. . On the other hand, it is considered that the tissue echoes Ec1 and Ec2 of the clutter components obtained from the living tissue among the reception echoes E1 and E2 are substantially only linear components in the fundamental band.

  Next, in step S2, an ultrasonic pulse p3 obtained by adding the ultrasonic pulse p1 and the ultrasonic pulse p2 is transmitted from the ultrasonic probe 3, and a reception echo E3 is acquired by the signal processing unit 7. The transmission of the ultrasonic pulse p3 and the acquisition of the reception echo E3 are performed under the control of the scan sequence control unit 9, similarly to the transmission of the ultrasonic pulse p1 and the ultrasonic pulse p2 and the acquisition of the reception echoes E1 and E2.

  That is, an ultrasonic pulse p3 having a frequency spectrum as shown in FIG. Then, as in the case of transmitting ultrasonic pulses p1 and p2, bubble echo Eb3 having a frequency spectrum corresponding to the frequency spectrum of ultrasonic pulse p3 as shown in FIG. 4 as a nonlinear component in a wide region including the fundamental band. Is acquired. Of the reception echo E3 obtained by the ultrasonic pulse p3, the tissue echo Ec3 of the clutter component obtained from the living tissue is similar to the tissue echoes Ec1 and Ec2 that are the clutter components of the reception echoes E1 and E2. In the fundamental band, it is considered that there is almost only a linear component.

  In this manner, three types of ultrasonic pulses p1, p2, two ultrasonic pulses p1, p2 having different frequency spectra and an ultrasonic pulse p3 obtained by adding the two ultrasonic pulses p1, p2 are used. p3 is sequentially transmitted from the ultrasonic probe 3. Then, reception echoes E1, E2, and E3 corresponding to the ultrasonic pulses p1, p2, and p3 are acquired and temporarily stored in the signal processing unit 7. Each reception echo E1, E2, E3 includes bubble echoes Eb1, Eb2, Eb3, which are nonlinear components, and tissue echoes Ec1, Ec2, Ec3, which can be regarded as linear components, in the fundamental band. For convenience of explanation, the transmission order is the order of the ultrasonic pulses p1, p2, and p3, but the transmission order is not limited to the order of the ultrasonic pulses p1, p2, and p3.

Next, in step S3, the signal processor 7 performs a linear operation on the received echoes E1, E2, E3. That is, the signal processing unit 7 adds the reception echo E1 and the reception echo E2, and subtracts the reception echo E3. As described above, the reception echoes E1, E2, and E3 are respectively represented by the bubble echoes Eb1, Eb2, and Eb3 and the tissue echoes Ec1, as shown in the equations (1-1), (1-2), and (1-3). Ec2 and Ec3 are included.
[Equation 1]
E1 = Ec1 + Eb1 (1-1)
E2 = Ec2 + Eb2 (1-2)
E3 = Ec3 + Eb3 (1-3)

The tissue echo Ec3 corresponds to an ultrasonic pulse p3 obtained by adding two ultrasonic pulses p1 and p2 corresponding to the tissue echo Ec1 and the tissue echo Ec2, respectively, and each tissue echo Ec1, Ec2, Since Ec3 can be regarded as only a substantially linear component, Expression (2) is established.
[Equation 2]
Ec3 = Ec1 + Ec2 (2)

On the other hand, since each of the bubble echoes Eb1, Eb2, and Eb3 is a nonlinear component, Expression (3) is established.
[Equation 3]
Eb3 ≠ Eb1 + Eb2 (3)

From equation (1-1), equation (1-2), equation (1-3), equation (2), and equation (3), the received echo E1 and the received echo E2 are added, and the received echo E3 is subtracted. Equation (4) is obtained.
[Equation 4]
E1 + E2-E3 = Ec1 + Eb1 + Ec2 + Eb2-Ec3-Eb3
= Eb1 + Eb2-Eb3
= Eb (4)

  That is, the result of adding the reception echo E1 and the reception echo E2 and subtracting the reception echo E3 is a pulse signal Eb containing only a bubble echo component that is a nonlinear component in the fundamental band of each reception echo E1, E2, E3. It becomes. In other words, the tissue echoes Ec1, Ec2, and Ec3 that can be considered to be composed of only substantially linear components in the fundamental band can be removed from the reception echoes E1, E2, and E3 by linear calculation.

  On the other hand, the bubble echoes Eb1, Eb2, and Eb3 generally have higher signal strengths than the tissue echoes Ec1, Ec2, and Ec3 in the fundamental wave band. In addition, since there are many nonlinear responses to the ultrasonic waves of bubbles in the fundamental band, bubble echoes, which are nonlinear components from the bubbles, remain as pulse signals Eb by linear calculation.

  The pulse signal Eb obtained by such signal processing is given from the signal processing unit 7 to the detection unit 8.

  Next, in step S4, the fundamental wave band of the pulse signal Eb is imaged as an imaging band. The imaging band of the pulse signal Eb is shown in FIG. For this purpose, the detection unit 8 performs envelope detection of the pulse signal Eb and gives the detection result to the display unit 11 as a detection signal. Then, the display unit 11 generates a video signal for monitor display from the detection signal received from the detection unit 8 and gives the generated video signal to the monitor 4 for display.

  As a result, the contrast image of the blood vessel of the subject is displayed on the monitor 4. Since this contrast image is generated from the non-linear component remaining in the fundamental band by linear calculation, the echo from the tissue is suppressed, while the echo from the bubble is selectively used for imaging. Moreover, since echoes from bubbles having different diameters are used for imaging, a contrast image in which contrast blood vessels are rendered better is obtained.

  By the way, in a contrast image in which such tissue echoes are suppressed, it may be difficult to set or maintain a good cross section.

  Therefore, in step S5, a tissue image is generated and displayed together with the contrast image. For generation of the tissue image, the reception echo before linear addition used for generation of the contrast image can be used.

  FIG. 6 is a block diagram showing the flow of signals between the received echo used as contrast image data and the received echo used as background tissue image data in the ultrasonic diagnostic apparatus 1 shown in FIG.

  As shown in FIG. 6, the received echoes E1, E2, and E3 are respectively guided to the signal processing unit 7 to be subjected to linear addition, and then output to the detection unit 8 as a contrast image signal. . A detection signal obtained from the pulse signal for the contrast image is given to the display unit 11 and displayed on the monitor 4 as a contrast image.

  Here, an arbitrary received echo before linear addition in the signal processing unit 7, for example, a received echo E1, is acquired by the detection unit 8 as a signal for a tissue (B-mode) image. Then, the detection unit 8 detects the tissue echo component included in the reception echo E1, and provides it to the display unit 11 as a detection signal for the tissue image. Further, a video signal of a tissue image is generated from the detection signal by the display unit 11 for monitor display, and the generated video signal is given to the monitor 4 so that the tissue image is displayed.

  That is, by handling the received echoes in parallel in the signal processing unit 7, the detection unit 8, and the display unit 11, not only a contrast image but also a tissue image can be generated and displayed. The contrast image and the tissue image generated in this way can be displayed on the monitor 4 by an arbitrary display method.

  FIG. 7 is a schematic diagram showing an example in which a contrast image and a background tissue image are displayed in parallel on the monitor 4 in the ultrasonic diagnostic apparatus 1 shown in FIG. 8 is a schematic diagram showing an example in which a contrast image and a background tissue image are superimposed and displayed on the monitor 4 in the ultrasonic diagnostic apparatus 1 shown in FIG. Further, FIG. 9 is a schematic diagram showing an example in which a contrast image and a background tissue image are watermark-displayed on the monitor 4 in the ultrasonic diagnostic apparatus 1 shown in FIG.

  As shown in FIGS. 7, 8, and 9, the contrast image and the tissue image are displayed in parallel, superimposed, and watermarked respectively, and the display can be switched to display the contrast image and the tissue image by switching the display screen. It is.

  In other words, the ultrasonic diagnostic apparatus 1 as described above transmits a plurality of ultrasonic pulses having different frequency distributions (frequency spectra) and an ultrasonic pulse obtained by linearly adding the ultrasonic pulses, and the former ultrasonic pulse. The difference between the reception echo addition result for the signal and the reception echo for the latter ultrasonic pulse is taken, and the fundamental band of the difference result is visualized.

  For this reason, echoes from tissues can be sufficiently suppressed, and echoes from bubbles that respond to different frequencies, that is, bubbles having different radii can be visualized. Thereby, the sensitivity of the ultrasonic diagnostic apparatus 1 can be improved.

  In addition, although shown about the example which transmits two ultrasonic pulses from which a center frequency differs, after transmitting similarly the ultrasonic pulse which synthesize | combined N ultrasonic pulses from which a center frequency differs, and N ultrasonic pulses, Each received echo may be linearly added.

  Next, a modified example of the combination of frequency spectra of each ultrasonic pulse transmitted in the ultrasonic diagnostic apparatus 1 will be described.

  FIG. 10 is a diagram showing a modification of the combination of frequency spectra of each ultrasonic pulse transmitted in the ultrasonic diagnostic apparatus 1 shown in FIG.

  As shown in FIG. 10, the ultrasonic pulse p1, the ultrasonic pulse p2, and the ultrasonic pulse p3 can be set to various frequency spectra. The ultrasonic pulses p1 and p2 can be set by changing at least one of the center frequency, amplitude, and band. The ultrasonic pulses p1 and p2 can be sequentially transmitted from the ultrasonic probe 3 toward the microbubbles in the subject with at least one of the phase and the transmission focal point being different. In the example of FIG. 10, an ultrasonic pulse p1 having a frequency spectrum with a center frequency f1, an amplitude A1, and a band B1 is transmitted from the ultrasonic probe 3 at the phase C1 and the transmission focal point F1. On the other hand, an ultrasonic pulse p2 having a frequency spectrum of center frequency f2, amplitude A2, and band B2 is transmitted from the ultrasonic probe 3 at phase C2 and transmission focal point F2.

  The ultrasonic pulse p3 obtained by synthesizing the ultrasonic pulse p1 and the ultrasonic pulse p2 is obtained by linearly adding the ultrasonic pulse p1 and the ultrasonic pulse p2, changing the amplitude to A times, and changing the phase to “ This is changed by ΔC (C2-C1) ".

  Then, reception echoes E1, E2, E3 obtained by transmitting such ultrasonic pulses p1, p2, p3 are acquired in the signal processing unit 7.

The signal processing unit 7 performs phase correction for shifting the phase of the reception echo E3 obtained by the ultrasonic pulse p3 by “−ΔC” and amplitude correction for increasing the amplitude to 1 / A times. Then, as shown in Expression (5), the reception echo E3 ′ after phase correction and amplitude correction is subtracted from the addition result of the reception echo E1 and the reception echo E2 obtained by transmission of the ultrasonic pulse p1 and the ultrasonic pulse p2, respectively. As a result, the pulse signal Eb including only the bubble echo component is generated.
[Equation 5]
Eb = E1 + E2-E3 ′ (5)

  As described above, a plurality of ultrasonic pulses having arbitrary different frequency spectra and ultrasonic pulses obtained by synthesizing all or a part of these ultrasonic pulses by linear calculation may be transmitted.

  In other words, the amplitude and phase of the transmitted ultrasonic pulse are set to arbitrary values as necessary, while the amplitude and / or phase correction of the received echo is performed according to the amplitude and phase of the transmitted ultrasonic pulse. be able to. Therefore, it is possible to generate an ultrasound image that matches the imaging conditions and purpose.

For example, amplitude correction can be performed to increase the amplitude of the received echo while sufficiently reducing the amplitude of the transmitted ultrasonic pulse to the extent that the bubble injected into the subject as a contrast agent is not destroyed. In addition, the phases of ultrasonic pulses transmitted to obtain a target reception echo can be reversed with each other, and the ultrasonic pulse p3 can be set to − (ultrasonic pulse p1 + ultrasonic pulse p2). The generation process of the pulse signal Eb in this case is as shown in Expression (6), and the signal component from the tissue is suppressed and the signal component from the bubble remains.
[Equation 6]
Eb = E1 + E2 + E3 (6)

  According to the ultrasonic diagnostic apparatus 1 and its control program of the present embodiment, the ultrasonic echoes from a larger number of bubbles with different radii are visualized while suppressing the ultrasonic echoes from the living tissue, thereby achieving higher sensitivity. With this, it is possible to easily recognize the shadows caused by bubbles.

  FIG. 11 is a configuration diagram showing a second embodiment of the ultrasonic diagnostic apparatus according to the present invention.

  An ultrasonic diagnostic apparatus 1A according to the second embodiment is configured by providing an ultrasonic probe 3 and a monitor 4 in an apparatus main body 2A. The apparatus main body 2A includes a transmission / reception unit 5, an A / D converter 6, a signal processing unit 7, a detection unit 8, a scan sequence control unit 9A, a system control unit 10, and a display unit 11. Each component of the apparatus main body 2A can be constructed by a circuit or by reading a control program into a CPU of a computer. In the ultrasonic diagnostic apparatus 1A shown in FIG. 11, the same components as those of the ultrasonic diagnostic apparatus 1 shown in FIG.

  In addition to the functions of the scan sequence control unit 9, the scan sequence control unit 9A generates a scan sequence so that ultrasonic pulses p1 and p4 whose frequency bands do not overlap each other are transmitted from the ultrasonic probe 3 at regular intervals. To do. The ultrasonic pulses p1 and p4 are preferably in a relatively narrow frequency band.

  Next, the operation of the ultrasonic diagnostic apparatus 1A will be described.

  FIG. 12 is a flowchart showing a procedure when blood flow is visualized by contrast echo method using microbubbles as a contrast agent by the ultrasonic diagnostic apparatus 1A shown in FIG. 11, and numerals are added to S in the figure. Reference numeral indicates each step of the flowchart.

  For steps S11 to S13 and step S15, the ultrasonic pulse p2 is replaced with the ultrasonic pulse p4, and the ultrasonic pulse p3 is replaced with the ultrasonic pulse p5, so that steps S1 to S3 described with reference to FIG. And step S5 is applied mutatis mutandis. For convenience of explanation, the transmission order is the order of the ultrasonic pulses p1, p4, and p5, but the transmission order is not limited to the order of the ultrasonic pulses p1, p4, and p5.

  FIG. 13 is a schematic diagram illustrating an example of a frequency spectrum corresponding to the ultrasonic pulses p1, p4, and p5 sequentially transmitted from the ultrasonic probe 3 in steps S11 and S12. In addition, each frequency spectrum shown in FIG. 13 is a modification of each frequency spectrum shown in FIG. 3 and FIG.

  The horizontal axis in FIG. 13 indicates the frequency. FIG. 13 shows an ultrasonic pulse p5 obtained by adding an ultrasonic pulse p1 having an ultrasonic spectrum with a center frequency f1, an ultrasonic pulse p4 having an ultrasonic spectrum with a center frequency f4, and ultrasonic pulses p1 and p4. It shows.

  In step S14, the band that does not overlap the fundamental band of the pulse signal Eb is visualized as an imaging band. The imaging band of the pulse signal Eb is shown in FIG. Then, the display unit 11 generates a video signal for monitor display from the detection signal received from the detection unit 8 and gives the generated video signal to the monitor 4 for display.

  For example, when an image of a moving organ such as the heart is visualized, a displacement occurs in each portion between the received signals of the rate due to the influence of the motion. As a result, the fundamental wave remains undisturbed, causing motion artifacts on the ultrasound image. Therefore, in the ultrasonic diagnostic apparatus 1A of the present embodiment, a tissue echo is reduced by imaging a band where the fundamental wave bands in step S14 do not overlap, that is, a region where no tissue echo exists, and motion on the ultrasound image is reduced. Artifacts can be reduced.

  Moreover, the echo of the center frequency f1 of the ultrasonic pulse p1 is derived from non-linearity and includes an integer multiple harmonic component. Therefore, it is preferable that the center frequency f4 of the ultrasonic pulse p4 is set to an integer multiple of 2 or more of the center frequency f1 of the ultrasonic pulse p1, and the band in which the fundamental band does not overlap is visualized as an imaging band.

  According to the ultrasonic diagnostic apparatus 1A of the present embodiment and its control program, it is possible to achieve higher sensitivity by imaging ultrasonic echoes from bubbles of different radii while suppressing ultrasonic echoes from living tissue. With this, it is possible to easily recognize the shadows caused by bubbles.

  Further, according to the ultrasonic diagnostic apparatus 1A and the control program thereof according to the present embodiment, the motion artifact of the ultrasonic image can be reduced by setting the fundamental wave component not to be included in the imaging band.

  FIG. 15 is a block diagram showing a third embodiment of the ultrasonic diagnostic apparatus according to the present invention.

  An ultrasonic diagnostic apparatus 1B according to the third embodiment is configured by providing an ultrasonic probe 3 and a monitor 4 in an apparatus main body 2B. The apparatus body 2B includes a transmission / reception unit 5, an A / D converter 6, a signal processing unit 7, a detection unit 8, a scan sequence control unit 9B, a system control unit 10, and a display unit 11. Each component of the apparatus main body 2B can be constructed by a circuit or by causing a CPU of a computer to read a control program. In the ultrasonic diagnostic apparatus 1B shown in FIG. 15, the same elements as those of the ultrasonic diagnostic apparatus 1 shown in FIG.

  In addition to the functions of the scan sequence control unit 9, the scan sequence control unit 9B transmits one of the ultrasonic pulses p1 and p2 having different frequency spectrums from the ultrasonic probe 3 at regular intervals by inverting one phase. A scan sequence is generated as follows. The ultrasonic diagnostic apparatus 1B can be combined with the ultrasonic diagnostic apparatus 1A.

  Next, the operation of the ultrasonic diagnostic apparatus 1B will be described.

  FIG. 16 is a flowchart showing a procedure for imaging a blood flow by contrast echo method using microbubbles as a contrast agent by the ultrasonic diagnostic apparatus 1B shown in FIG. 15, and a number is added to S in the figure. Reference numeral indicates each step of the flowchart.

  In step S21, one of the pulse waveforms of the ultrasonic pulse p1 having the center frequency f1 and the ultrasonic pulse p2 having the center frequency f2 is phase-inverted to perform ultrasonic transmission and receive the reception echoes E1 and E2.

  Note that steps S2 to S5 described with reference to FIG. 2 are applied to steps S22 to S25, respectively. For convenience of explanation, the transmission order is the order of the ultrasonic pulses p1, p2, and p3, but the transmission order is not limited to the order of the ultrasonic pulses p1, p2, and p3.

  FIG. 17 shows an example of two pulse waveforms when two ultrasonic pulses having different frequency spectra (center frequencies in FIGS. 17 and 18) are transmitted in the same phase and a pulse waveform obtained by synthesizing these pulse waveforms. FIG. On the other hand, FIG. 18 shows three pulse waveforms transmitted by the ultrasonic diagnostic apparatus 1B, two pulse waveforms when one of two ultrasonic pulses having different center frequencies is transmitted with phase inversion, and those pulse waveforms. It is a figure which shows an example with the pulse waveform which synthesize | combined the pulse waveform.

  The horizontal axis of FIG. 17 and FIG. 18 shows time. The three pulse waveforms shown in FIG. 17 are the same as the pulse waveforms of the ultrasonic pulses p1 and p2 when the ultrasonic pulses p1 and p2 having different center frequencies are transmitted in the same phase. And a pulse waveform obtained by synthesizing the pulse waveform when transmitting by.

  On the other hand, the three pulse waveforms shown in FIG. 18 are the pulses of the ultrasonic pulses p1 and p2 when one of the ultrasonic pulses p1 and p2 having different center frequencies (for example, the ultrasonic pulse p2) is transmitted with the phase inverted. The waveform and the pulse waveform of the ultrasonic pulse p3 synthesized by linearly calculating the phase-inverted ultrasonic pulses p1 and p2 are shown. It can be seen that the peak of the pulse waveform of the ultrasonic pulse p3 shown in FIG. 18 is reduced by the phase inversion of the ultrasonic pulse p2 compared to the pulse waveform of the ultrasonic pulse p3 shown in FIG. As shown in FIG. 18, when the peak of the pulse waveform of the ultrasonic pulse p3 is reduced, there is an advantage that the saturation of the echo signal received by the transmission of the ultrasonic pulse p3 is reduced. In other words, as shown in FIG. 18, when the peak of the ultrasonic pulse p3 decreases, there is an advantage that the gain of the echo signal received by ultrasonic transmission using the ultrasonic pulse p3 can be set large.

  FIG. 19 is a diagram showing frequency spectra of bubble echoes and tissue echoes depending on whether one of the ultrasonic pulses is phase-inverted.

  The upper part of FIG. 19 shows frequency spectra of bubble echoes and tissue echoes when ultrasonic pulses p1, p2, and p3 are ultrasonically transmitted using the pulse waveforms shown in FIG. On the other hand, the lower part of FIG. 19 shows frequency spectra of bubble echoes and tissue echoes when ultrasonic pulses p1, p2, and p3 are ultrasonically transmitted using the pulse waveforms shown in FIG.

  According to FIG. 19, it is understood that when ultrasonic transmission is performed with each pulse waveform shown in FIG. 18, the signal intensity of the tissue echo can be reduced while the signal intensity of the bubble echo can be increased by decreasing the saturation of the echo signal. When the echo signal is saturated, the tissue echo becomes Ec1 ≠ Ec2 ≠ Ec3, and the clutter component cannot be canceled by linear calculation.

  According to the ultrasonic diagnostic apparatus 1B and its control program of the present embodiment, it is possible to obtain higher sensitivity by visualizing ultrasonic echoes from bubbles of different radii while suppressing ultrasonic echoes from living tissue. With this, it is possible to easily recognize the shadows caused by bubbles.

  Further, according to the ultrasonic diagnostic apparatus 1B and its control program of the present embodiment, the signal intensity of the bubble echo can be increased by reducing the peak of the pulse waveform of the ultrasonic pulse p3 by the phase inversion of the ultrasonic pulse p2. The signal intensity of tissue echo can be reduced.

  FIG. 20 is a configuration diagram showing a fourth embodiment of the ultrasonic diagnostic apparatus according to the present invention.

  An ultrasonic diagnostic apparatus 1C according to the fourth embodiment is configured by providing an ultrasonic probe 3 and a monitor 4 in an apparatus main body 2C. The apparatus main body 2C includes a transmission / reception unit 5, an A / D converter 6, a signal processing unit 7, a detection unit 8, a scan sequence control unit 9C, a system control unit 10, and a display unit 11. Each component of the apparatus main body 2C can be constructed by a circuit or by causing a CPU of a computer to read a control program. In the ultrasonic diagnostic apparatus 1C shown in FIG. 20, the same components as those in the ultrasonic diagnostic apparatus 1 shown in FIG.

  The scan sequence control unit 9C is different from the scan sequence control unit 9 in the usage method of the ultrasonic probe 3 and the transmitted ultrasonic pulse. The ultrasonic diagnostic apparatus 1C can be combined with at least one of the ultrasonic diagnostic apparatus 1, the ultrasonic diagnostic apparatus 1A, and the ultrasonic diagnostic apparatus 1B.

  Regarding the operation of the ultrasonic diagnostic apparatus 1 </ b> C, the ultrasonic diagnostic apparatus 1, the ultrasonic diagnostic apparatus 1 </ b> A or the ultrasonic diagnosis shown in FIG. 1 is used except for the method of using the ultrasonic probe 3 and the transmitted ultrasonic pulse. It is not substantially different from the operation of the device 1B.

  FIG. 21 to FIG. 24 are diagrams for explaining an ultrasonic pulse transmission method in the ultrasonic diagnostic apparatus 1C shown in FIG.

  As shown in FIGS. 21 to 24, in the ultrasonic diagnostic apparatus 1C, the transmission opening 3a of the ultrasonic probe 3 used for transmission / reception differs for each transmission / reception. That is, the transmission aperture 3a of the ultrasonic probe 3 is divided into a plurality of groups each including at least one different ultrasonic transducer. However, the transmission aperture 3a of the ultrasonic probe 3 is easy to control and practical to be divided into a plurality of groups having mutually exclusive ultrasonic transducers as components.

  For example, as shown in FIG. 21, in the case of an ultrasonic probe 3 having a probe surface in which a plurality of transmission openings 3a are arranged in a one-dimensional manner, the first transmission opening group A and the second transmission opening group B are set. Is done. For example, the first transmission aperture group A and the second transmission aperture group B have no common part and are mutually exclusive.

  Then, as indicated by the hatched portion in FIG. 22, only the transmission aperture 3a belonging to the first transmission aperture group A is used for transmission first, and the center frequency f1 is transmitted from the transmission aperture 3a belonging to the first transmission aperture group A. A first ultrasonic pulse p1 having a frequency spectrum is transmitted. Then, a first sound field is formed by the first ultrasonic pulse p1, and a reception echo E1 corresponding to the first sound field can be obtained.

  Next, as shown by the hatched portion in FIG. 23, only the transmission aperture 3a belonging to the second transmission aperture group B is used for transmission, and the first ultrasonic wave is transmitted from the transmission aperture 3a belonging to the second transmission aperture group B. A second ultrasonic pulse p2 having a frequency spectrum with a center frequency f2 different from the center frequency f1 of the pulse p1 is transmitted. Then, a second sound field is formed by the second ultrasonic pulse p2, and a reception echo E2 corresponding to the second sound field can be obtained. Here, the parameters such as the band B2 and the amplitude A2 other than the center frequency f2 of the second ultrasonic pulse p2 may be set to be different from the parameters such as the band B1 and the amplitude A1 of the first ultrasonic pulse p1. .

  Subsequently, as shown in FIG. 24, both the transmission aperture 3a belonging to the first transmission aperture group A and the transmission aperture 3a belonging to the second transmission aperture group B are simultaneously used for transmission. The first ultrasonic pulse p1 having the frequency spectrum of the center frequency f1 is transmitted from the transmission aperture 3a belonging to the first transmission aperture group A, while the transmission aperture 3a belonging to the second transmission aperture group B is transmitted. The second ultrasonic pulse p2 having a frequency spectrum of the center frequency f2 is transmitted. Then, a third sound field is formed by the first ultrasonic pulse p1 and the second ultrasonic pulse p2, and a reception echo E3 corresponding to the third sound field can be obtained.

  As described above, when the first ultrasonic pulse p1 and the second ultrasonic pulse p2 are transmitted at the same time to form the third sound field, the reception echo E3 obtained by the third sound field becomes the first supersonic wave. This is equivalent to the reception echo obtained when the third ultrasonic pulse p3 obtained by synthesizing the acoustic pulse p1 and the second ultrasonic pulse p2 is transmitted. In other words, the simultaneous transmission of the first ultrasonic pulse p1 and the second ultrasonic pulse p2 from mutually different transmission openings 3a of the ultrasonic probe 3 is substantially equivalent to the first ultrasonic pulse p1 and the second ultrasonic pulse p1. This corresponds to transmitting the third ultrasonic pulse p3 obtained by synthesizing the ultrasonic pulse p2.

  That is, the ultrasonic diagnostic apparatus 1C transmits the ultrasonic pulses p1 and p2 before synthesis from different transmission openings 3a, and synthesizes the ultrasonic pulse p3 to be synthesized not as a transmission pulse but as a transmission sound field. It is a thing. In other words, the ultrasonic diagnostic apparatus 1C is used to transmit the ultrasonic pulses p1 and p2 while transmitting the ultrasonic pulses p1 and p2 before synthesis by switching the channel used in the ultrasonic probe 3. An ultrasonic pulse p3 is synthesized as a transmission sound field using a channel.

  For this reason, as in the case of the ultrasonic diagnostic apparatus 1 shown in FIG. 1, echoes from bubbles having different radii can be visualized while suppressing tissue echoes, so that blood flow visualization sensitivity can be improved. . Furthermore, even when the pulsar provided in the transmission / reception unit 5 does not have sufficient performance to accurately generate and transmit the ultrasonic pulse p3 to be synthesized, the ultrasonic pulse p3 is synthesized as a transmission sound field. Therefore, the effect of suppressing the tissue echo can be sufficiently obtained.

  In addition, the transmission order of FIG.22, FIG.23 and FIG.24 can be changed arbitrarily. Further, the transmission aperture 3a can be divided into three or more transmission aperture groups so that three or more ultrasonic pulses having different frequency spectra can be synthesized as a sound field. In addition, a common ultrasonic transducer may exist between the transmission aperture groups as long as the target sound field can be formed. Alternatively, there may be an ultrasonic transducer that is not used.

  Further, phase correction and amplitude correction can be performed in the linear calculation of the received echo in the signal processing unit 7.

  According to the ultrasonic diagnostic apparatus 1C and its control program of the present embodiment, it is possible to obtain higher sensitivity by visualizing ultrasonic echoes from bubbles of different radii while suppressing ultrasonic echoes from living tissue. With this, it is possible to easily recognize the shadows caused by bubbles.

  FIG. 25 is a block diagram showing a fifth embodiment of the ultrasonic diagnostic apparatus according to the present invention.

  An ultrasonic diagnostic apparatus 1D of the fifth embodiment is configured by providing an ultrasonic probe 3 and a monitor 4 in an apparatus main body 2D. The apparatus main body 2D includes a transmission / reception unit 5, an A / D converter 6, a signal processing unit 7, a detection unit 8, a scan sequence control unit 9D, a system control unit 10, and a display unit 11. Each component of the apparatus main body 2D can be constructed by a circuit or by causing a CPU of a computer to read a control program. In the ultrasonic diagnostic apparatus 1D, a case of convex scan or linear scan is assumed. In the ultrasonic diagnostic apparatus 1D shown in FIG. 25, the same components as those in the ultrasonic diagnostic apparatus 1 shown in FIG.

  The scan sequence control unit 9D is different from the scan sequence control unit 9 in the usage method of the ultrasonic probe 3 and the transmitted ultrasonic pulse. The ultrasonic diagnostic apparatus 1D can be combined with at least one of the ultrasonic diagnostic apparatus 1A and the ultrasonic diagnostic apparatus 1B.

  Regarding the operation of the ultrasonic diagnostic apparatus 1D, the ultrasonic diagnostic apparatus 1, the ultrasonic diagnostic apparatus 1A, or the ultrasonic diagnosis shown in FIG. 1 is used except for the method of using the ultrasonic probe 3 and the transmitted ultrasonic pulse. It is not substantially different from the operation of the device 1B.

  26 and 27 are diagrams for explaining an ultrasonic pulse transmission method in the ultrasonic diagnostic apparatus 1D shown in FIG.

  As shown in FIGS. 26 and 27, in the ultrasonic diagnostic apparatus 1D, the ultrasonic pulse p6 and the ultrasonic pulse p7 are alternated for each ultrasonic transducer group (for example, 16 ch) of a certain ch (channel) provided in the ultrasonic probe 3. Assigned to. However, it is preferable that the transmission aperture of the ultrasonic probe 3 is divided into a plurality of groups each including an ultrasonic transducer that does not overlap each other.

  FIG. 26 illustrates a case where a transmission beam (reception beam) is formed by a transmission aperture group set regardless of the number of channels of the ultrasonic transducer group. In this way, when the reception beam R is formed based on the transmission aperture group A and the transmission aperture group B (for example, both 20ch), the reception beam RA of the transmission aperture group A and the reception beam RB of the transmission aperture group B are super The ratio of p6 and p7 of the sound wave pulse is different. Therefore, if the reception beams RA and RB are reception beams formed from the ultrasonic pulse p1 (or the ultrasonic pulse p2) of the ultrasonic diagnostic apparatus 1, the degree of nonlinear effect and saturation differ.

  On the other hand, FIG. 27 shows a transmission aperture group used in the ultrasonic diagnostic apparatus 1D, and a transmission beam (reception beam) is formed by a transmission aperture group set to a positive even multiple of the number of channels of the ultrasonic transducer group. Is described. In this way, when the reception beam R is formed based on the transmission aperture group A and the transmission aperture group B (for example, both 32 channels), the reception beam RA of the transmission aperture group A and the reception beam RB of the transmission aperture group B are super The ratios of p6 and p7 of the sonic pulse are the same.

  FIG. 28 is a diagram for explaining an ultrasonic image generated by the ultrasonic diagnostic apparatus 1D shown in FIG.

  The upper part of FIG. 28 shows an ultrasonic image generated based on the transmission aperture set regardless of the number of channels of the ultrasonic transducer group as shown in FIG. On the other hand, as shown in FIG. 27, an ultrasonic image generated based on the transmission aperture set at twice the number of channels of the ultrasonic transducer group is shown.

  The ultrasonic image in the lower part of FIG. 28 has less nonlinear effects and saturation differences compared to the ultrasonic image in the upper part of FIG. 28, and the vertical stripes appearing on the ultrasonic image are thin. I understand.

  According to the ultrasonic diagnostic apparatus 1D and the control program thereof of the present embodiment, the ultrasonic echo from the bubbles with different radii is visualized while suppressing the ultrasonic echo from the living tissue, thereby increasing the sensitivity. With this, it is possible to easily recognize the shadows caused by bubbles.

  Further, according to the ultrasonic diagnostic apparatus 1D of this embodiment and its control program, the ratio of the ultrasonic transducer that transmits the ultrasonic pulse p1 in the transmission aperture to the ultrasonic transducer that transmits the ultrasonic pulse p2 is constant. By setting, the vertical stripe appearing on the ultrasonic image can be thinned.

1 is a configuration diagram showing a first embodiment of an ultrasonic diagnostic apparatus according to the present invention. FIG. The flowchart which shows the procedure at the time of performing the imaging of the blood flow by the contrast echo method which used the microbubble as a contrast agent by the ultrasonic diagnostic apparatus shown in FIG. The schematic diagram which shows an example of the frequency spectrum corresponding to the some ultrasonic pulse transmitted in the ultrasound diagnosing device shown in FIG. The schematic diagram which shows an example of the frequency spectrum of the reception echo from the bubble each obtained by transmission of each ultrasonic pulse shown in FIG. The figure which shows the frequency band imaged in the ultrasonic diagnostic apparatus shown in FIG. The block diagram which showed the flow of the signal of the reception echo used as contrast image data and the reception echo used as background tissue image data in the ultrasonic diagnostic apparatus shown in FIG. The schematic diagram which shows the example which displayed the contrast image and the background tissue image on the monitor in parallel in the ultrasonic diagnostic apparatus shown in FIG. The schematic diagram which shows the example which superimposed and displayed the contrast image and the tissue image of the background on the monitor in the ultrasonic diagnostic apparatus shown in FIG. FIG. 3 is a schematic diagram showing an example in which a contrast image and a background tissue image are watermark-displayed on a monitor in the ultrasonic diagnostic apparatus shown in FIG. The figure which shows the modification of the combination of the frequency spectrum of each ultrasonic pulse transmitted in the ultrasonic diagnosing device shown in FIG. The block diagram which shows 2nd Embodiment of the ultrasonic diagnosing device which concerns on this invention. The flowchart which shows the procedure at the time of performing the imaging of the blood flow by the contrast echo method using the microbubble as a contrast agent by the ultrasonic diagnostic apparatus shown in FIG. FIG. 12 is a schematic diagram illustrating an example of a frequency spectrum corresponding to a plurality of ultrasonic pulses transmitted in the ultrasonic diagnostic apparatus illustrated in FIG. 11. The figure which shows the frequency band imaged in the ultrasonic diagnostic apparatus shown in FIG. The block diagram which shows 3rd Embodiment of the ultrasonic diagnosing device which concerns on this invention. The flowchart which shows the procedure at the time of performing the imaging of the blood flow by the contrast echo method using microbubble as a contrast agent by the ultrasonic diagnostic apparatus shown in FIG. The figure which shows an example of two pulse waveforms in the case of transmitting the two ultrasonic pulses from which a frequency spectrum differs mutually in the same phase, and the pulse waveform which synthesize | combined those pulse waveforms. The figure which shows an example of two pulse waveforms when one of two ultrasonic pulses having different center frequencies is transmitted with phase inversion, and a pulse waveform obtained by synthesizing these pulse waveforms. The figure which shows the frequency spectrum of the bubble echo and tissue echo at the time of transmitting ultrasonically with each pulse waveform shown in FIG. 17, and the frequency spectrum of the bubble echo and tissue echo at the time of transmitting ultrasonically with each pulse waveform shown in FIG. The block diagram which shows 4th Embodiment of the ultrasonic diagnosing device which concerns on this invention. The figure for demonstrating the transmission method of the ultrasonic pulse in the ultrasonic diagnosing device shown in FIG. The figure for demonstrating the transmission method of the ultrasonic pulse in the ultrasonic diagnosing device shown in FIG. The figure for demonstrating the transmission method of the ultrasonic pulse in the ultrasonic diagnosing device shown in FIG. The figure for demonstrating the transmission method of the ultrasonic pulse in the ultrasonic diagnosing device shown in FIG. The block diagram which shows 5th Embodiment of the ultrasonic diagnosing device which concerns on this invention. The figure for demonstrating the transmission method of the ultrasonic pulse in the ultrasonic diagnosing device shown in FIG. The figure for demonstrating the transmission method of the ultrasonic pulse in the ultrasonic diagnosing device shown in FIG. The figure for demonstrating the ultrasonic image produced | generated by ultrasonic diagnostic apparatus 1D shown in FIG.

Explanation of symbols

1, 1A, 1B, 1C, 1D Ultrasound diagnostic apparatus 2, 2A, 2B, 2C, 2D Device body 3 Ultrasonic probe 4 Monitor 5 Transmitter / receiver 6 A / D converter 7 Signal processor 8 Detectors 9, 9A, 9B , 9C, 9D Scan sequence control unit 10 System control unit 11 Display unit

Claims (30)

First received echo acquisition means for acquiring each received echo received by transmitting a plurality of ultrasonic pulses having different center frequencies to each other by an ultrasonic probe;
A second received echo acquisition means for transmitting an ultrasonic pulse having the same frequency component characteristics as a synthesized pulse obtained by synthesizing the plurality of ultrasonic pulses to the subject and acquiring a received echo;
A reception echo synthesis means for generating a synthesized signal by synthesizing the reception echo acquired by the first reception echo acquisition means and the reception echo acquired by the second reception echo acquisition means;
Image generating means for generating an image of an echo from the subject from the synthesized signal;
An ultrasonic diagnostic apparatus comprising: 2. The ultrasonic diagnosis according to claim 1, wherein the first reception echo acquiring unit changes at least one of a center frequency, an amplitude, and a band of the frequency spectrum as the plurality of ultrasonic pulses. apparatus. When transmitting the plurality of ultrasonic pulses, the first reception echo acquiring unit changes at least one of the phase, the transmission aperture, and the transmission focus for each of the plurality of ultrasonic pulses in addition to the center frequency. The ultrasonic diagnostic apparatus according to claim 2. The said 1st reception echo acquisition means reverses the phase of the pulse waveform of one ultrasonic pulse, when transmitting two ultrasonic pulses as these ultrasonic pulses. Ultrasonic diagnostic equipment. The ultrasonic diagnostic apparatus according to claim 3, wherein the transmission opening is a positive even multiple of an ultrasonic transducer group that transmits each ultrasonic pulse. The ultrasonic diagnostic apparatus according to claim 5, wherein the transmission opening is twice as large as the ultrasonic transducer group. The ultrasonic diagnostic apparatus according to claim 1, wherein the first reception echo acquisition unit sets the plurality of ultrasonic pulses so that frequency bands do not overlap each other. The ultrasonic diagnostic apparatus according to claim 7, wherein each center frequency of the plurality of ultrasonic pulses is set to an integer multiple of 2 or more. The reception echo synthesis means is configured to synthesize the reception echo acquired by the first reception echo acquisition means and the reception echo acquired by the second reception echo acquisition means by processing including addition / subtraction. The ultrasonic diagnostic apparatus according to claim 1. The reception echo synthesis means is configured to perform at least one amplitude correction of the reception echo acquired by the first reception echo acquisition means and the reception echo acquired by the second reception echo acquisition means. The ultrasonic diagnostic apparatus according to claim 1. The reception echo synthesis means is configured to perform phase correction of at least one of the reception echo acquired by the first reception echo acquisition means and the reception echo acquired by the second reception echo acquisition means. The ultrasonic diagnostic apparatus according to claim 1. A tissue image generation unit that generates a tissue image of the subject from at least one of the reception echo acquired by the first reception echo acquisition unit and the reception echo acquired by the second reception echo acquisition unit; The ultrasonic diagnostic apparatus according to claim 1, further comprising display means for displaying an image and the tissue image. The second received echo acquisition means is configured to generate a control signal for transmitting an ultrasonic pulse having the same frequency component characteristics as a synthesized pulse obtained by synthesizing the plurality of ultrasonic pulses from an ultrasonic probe. The ultrasonic diagnostic apparatus according to claim 1. The second reception echo acquisition means is configured to synthesize an ultrasonic pulse having the same frequency component characteristics as an ultrasonic pulse obtained by synthesizing the plurality of ultrasonic pulses as a transmission sound field. The ultrasonic diagnostic apparatus according to claim 1. The first reception echo acquisition unit is configured to transmit the plurality of ultrasonic pulses by switching channels of the ultrasonic probe, while the second reception echo acquisition unit is configured to transmit the plurality of ultrasonic pulses. The ultrasonic diagnostic apparatus according to claim 14, wherein the transmission sound field is synthesized by using a channel used for transmitting a sound wave pulse. The computer included in the ultrasound diagnostic device
First receiving a plurality of ultrasonic pulse center frequencies are different from each other to obtain a received echo of the received Taso respectively by the ultrasonic probe by being transmitted from the ultrasonic probe to the subject from the ultrasound probe Echo acquisition means,
Wherein the received echo received by the ultrasonic probe by the ultrasonic pulse is transmitted to the subject from the ultrasonic probe having the characteristics of the same frequency component as the synthetic pulse obtained by combining the plurality of ultrasonic pulses than Second received echo acquisition means for acquiring from the acoustic probe ;
A reception echo synthesizing unit that generates a composite signal by synthesizing the reception echo acquired by the first reception echo acquisition unit and the reception echo acquired by the second reception echo acquisition unit; and Image generation means for generating an echo image from the subject;
A control program for an ultrasound diagnostic apparatus, characterized in that The ultrasonic diagnosis according to claim 16, wherein the first reception echo acquiring unit changes at least one of a center frequency, an amplitude, and a band of the frequency spectrum as the plurality of ultrasonic pulses. Device control program. When transmitting the plurality of ultrasonic pulses, the first reception echo acquiring unit changes at least one of the phase, the transmission aperture, and the transmission focus for each of the plurality of ultrasonic pulses in addition to the center frequency. The control program for an ultrasonic diagnostic apparatus according to claim 17. The said 1st reception echo acquisition means reverses the phase of the pulse waveform of one ultrasonic pulse, when transmitting two ultrasonic pulses as these ultrasonic pulses. Control program for ultrasonic diagnostic equipment. 19. The control program for an ultrasonic diagnostic apparatus according to claim 18, wherein the transmission aperture is a positive even number multiple of an ultrasonic transducer group that transmits each ultrasonic pulse. 21. The control program for an ultrasonic diagnostic apparatus according to claim 20, wherein the transmission opening is twice as large as the ultrasonic transducer group. 17. The control program for an ultrasonic diagnostic apparatus according to claim 16, wherein the first reception echo acquisition means sets the plurality of ultrasonic pulses so that frequency bands do not overlap each other. The control program for an ultrasonic diagnostic apparatus according to claim 22, wherein each center frequency of the plurality of ultrasonic pulses is set to an integer multiple of 2 or more. The reception echo synthesis means synthesizes the reception echo acquired by the first reception echo acquisition means and the reception echo acquired by the second reception echo acquisition means by a process including addition and subtraction. A control program for an ultrasonic diagnostic apparatus according to claim 16. The reception echo synthesis means performs amplitude correction of at least one of the reception echo acquired by the first reception echo acquisition means and the reception echo acquired by the second reception echo acquisition means. Item 17. A control program for an ultrasonic diagnostic apparatus according to Item 16. The reception echo synthesis means performs at least one phase correction of the reception echo acquired by the first reception echo acquisition means and the reception echo acquired by the second reception echo acquisition means. Item 17. A control program for an ultrasonic diagnostic apparatus according to Item 16. Tissue image generation for generating a tissue image of the subject from at least one of the reception echo acquired by the first reception echo acquisition means and the reception echo acquired by the second reception echo acquisition means. Means and
Display means for displaying the image and the tissue image;
The control program for an ultrasonic diagnostic apparatus according to claim 16, wherein the control program is made to function as: The second received echo acquisition means generates a control signal for transmitting from the ultrasonic probe an ultrasonic pulse having the same frequency component characteristics as the synthesized pulse obtained by synthesizing the plurality of ultrasonic pulses. The control program for an ultrasonic diagnostic apparatus according to claim 16. 17. The second received echo acquisition unit synthesizes an ultrasonic pulse having the same frequency component characteristics as an ultrasonic pulse obtained by synthesizing the plurality of ultrasonic pulses as a transmission sound field. Control program for ultrasonic diagnostic equipment. The first reception echo acquisition means transmits the plurality of ultrasonic pulses by switching the channel of the ultrasonic probe, while the second reception echo acquisition means transmits the plurality of ultrasonic pulses. 30. The control program for an ultrasonic diagnostic apparatus according to claim 29, wherein the transmission sound field is synthesized by using a used channel.

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