JPH11137547A - Ultrasonic photographing method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an ultrasonic photographing method and the device wherein a photographing is performed by comprehensively utilizing a plurality of signals being included in the ultrasonic wave which returns from a micro baloon contrast medium. SOLUTION: An ultrasonic wave is cast on a specimen in which a micro baloon contrast medium is injected, and an image is formed based on the echo, and in this case, echos in a frequency zone B2 of the basic wave of the cast ultrasonic wave, and frequency zones B1, B3, B4 on the outside of the frequency zone B2 are respectively utilized for the image formation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic imaging method and apparatus, and more particularly, to a microballoon.
n) An ultrasonic imaging method and apparatus for a subject into which a contrast agent has been injected.

[0002]

2. Description of the Related Art Ultrasonic imaging using a contrast agent uses a microballoon contrast agent in which a large number of air bubbles (microballoons) having a diameter of about several μm are mixed in a liquid, and the non-linear echo (echo) source property is obtained. Contrast imaging is performed using the second harmonic echo based on

[0003]

The ultrasonic wave returning from the micro-balloon contrast agent contains various signals in addition to the second harmonic echo. One of them is the subharmonics (subharmonics) generated by the destruction of microballoons.
ics) ultrasound. It has half the fundamental frequency of the transmitted ultrasound. Subharmonics ultrasound is particularly pronounced when relatively hard microballoons break.

[0004] Also, acoustic emission (asAE: acoustically stimulated acoustic emiss) induced by transmitted ultrasonic waves.
ion). This is an ultrasonic signal having a frequency that is not correlated with the frequency of the transmitted ultrasonic wave.

Further, there is a signal derived from a phenomenon called scintillation, which was discovered by the present inventors. “Scintillation” is a phenomenon in which an echo signal undergoes random modulation in its phase and amplitude, and can be detected as Doppler of the echo signal.

[0006] As described above, various signals are included in the ultrasonic waves returned from the microballoon contrast agent. Conventionally, there has been no idea of performing ultrasonic imaging using the signals comprehensively.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide an ultra-small imaging system that comprehensively utilizes a plurality of signals contained in ultrasonic waves returning from a micro-balloon contrast agent. An object of the present invention is to realize a sound wave imaging method and apparatus.

[0008]

[Means for Solving the Problems]

(1) A first invention for solving the above problems is an ultrasonic imaging method for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium is injected and generating an image based on an echo of the ultrasonic wave. The echo in the frequency band of the fundamental wave of the waved ultrasonic wave and the echoes in the frequency bands on both sides thereof are respectively used for image generation.

(2) A second invention for solving the above problems is an ultrasonic imaging method for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium has been injected and generating an image based on the echo. Receiving an echo in the frequency band of the fundamental wave of the transmitted ultrasonic wave and an echo in a frequency band outside the same, and performing signal modification between the received signals or signals based on the received signals. .

(3) A third invention for solving the above problems is an ultrasonic imaging method for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium has been injected and generating an image based on the echo. Receiving the echo in the frequency band of the fundamental wave of the transmitted ultrasonic wave and the echo in the frequency band outside thereof, and adjusting the time difference between the received signals;
It is characterized by the following.

(4) According to a fourth aspect of the present invention, an ultrasonic wave is transmitted to a subject into which a microballoon contrast medium is injected, and an echo in a frequency band of a fundamental wave of the transmitted ultrasonic wave and both sides of the echo are transmitted. The transmission / reception unit receives the echoes in the frequency bands, and the image generation unit generates an image based on a plurality of echo signals having different frequency bands received by the transmission / reception unit.

(5) According to a fifth aspect of the present invention, an ultrasonic wave is transmitted to a subject into which a microballoon contrast medium has been injected, and the echo in the frequency band of the fundamental wave of the transmitted ultrasonic wave and the outside of the echo. Transmitting / receiving means for receiving echoes in frequency bands, signal modifying means for performing signal modification between a plurality of echo signals or signals based on the echo signals having different frequency bands received by the transmitting / receiving means, and a signal having passed the signal modification Image generating means for generating an image based on
It is characterized by having.

(6) According to a sixth aspect of the present invention to solve the above-mentioned problems, an ultrasonic wave is transmitted to a subject into which a microballoon contrast agent is injected, and an echo in a frequency band of a fundamental wave of the transmitted ultrasonic wave and an echo outside the same are transmitted. Transmitting and receiving means for receiving echoes in each frequency band, a time difference adjusting means for adjusting a time difference between a plurality of echo signals having different frequency bands received by the transmitting and receiving means, and a signal on which the time difference is adjusted by the time difference adjusting means. Image generating means for generating an image.

In the first to sixth aspects of the present invention, it is preferable to display images based on a plurality of echo signals having different frequency bands in different display colors in order to facilitate identification of a contrast agent image.

Further, in the first to sixth aspects, displaying an image based on echoes in the frequency band of the fundamental wave and an image based on echoes in other frequency bands in combination with the position with respect to the body tissue is preferable. This is preferable in that a contrast agent image having a clear relationship is displayed.

In the first to sixth aspects of the present invention, it is preferable to display images based on a plurality of echo signals having different frequency bands side by side on one screen in order to facilitate comparison and comparison of images. .

In the second invention or the fifth invention, it is preferable to insert the contrast agent image into the in-vivo tissue image by the signal modification in order to clarify the contrast agent image. In this case, it is preferable to cut out the in-vivo tissue image at the portion where the contrast agent image is fitted by the signal modification in order to visualize the in-vivo tissue image of the fitted portion.

In the second invention or the fifth invention, the in-vivo tissue image is enhanced by using the contrast agent image as a mask by the signal modification, in order to clarify the in-vivo tissue image image of the contrast agent injection portion. preferable.

(Function) In the first invention or the fourth invention, imaging is performed by utilizing the echo in the frequency band of the fundamental wave of the transmitted ultrasonic wave and the echoes in the frequency bands on both sides thereof.

In the second invention or the fifth invention, signal modification is performed between a plurality of echo signals having different frequency bands or signals based on the echo signals, and an image is generated based on the signal subjected to the signal modification. And obtain various display images.

In the third invention or the sixth invention, an image having no positional displacement between the echo signals is obtained by adjusting the time difference between a plurality of echo signals having different frequency bands.

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiment.

FIG. 1 shows a block (bloc) of an ultrasonic imaging apparatus.
k) Show the figure. This apparatus is an example of an embodiment of the ultrasonic imaging apparatus of the present invention. An example of an embodiment of the device of the present invention is shown by the configuration of the present device. An example of an embodiment of the method of the present invention is shown by the operation of the present apparatus.

(Configuration) The configuration of the present apparatus will be described. As shown in FIG. 1, the present apparatus has an ultrasonic probe (probe) 2. The ultrasonic probe 2 includes, for example, an unillustrated ultrasonic transducer array (a) formed along an arc that protrudes forward.
rray). That is, the ultrasonic probe 2 is a convex probe. The ultrasonic probe 2 is used in contact with the subject 4 by an operator. A microballoon contrast agent 40 is injected into the subject 4.

The ultrasonic probe 2 is connected to the transmission / reception unit 6. The transmitting / receiving unit 6 supplies a drive signal to the ultrasonic probe 2 to transmit ultrasonic waves into the subject 4. The transmission / reception unit 6 also receives an echo from the subject 4 that the ultrasonic probe 2 has received.
The ultrasonic probe 2 and the transmission / reception unit 6 are an example of an embodiment of a transmission / reception unit in the present invention.

FIG. 2 shows a block diagram of the transmission / reception section 6. In the figure, a transmission timing (timing) generating circuit 602
Is configured to periodically generate a transmission timing signal and input the transmission timing signal to a transmission beam former 604.

The transmission beamformer 604 performs transmission beamforming (beam fo) based on the transmission timing signal.
rming) signal, that is, a plurality of drive signals for driving a plurality of ultrasonic transducers (transducers) in the ultrasonic transducer array with a time difference, and a transmission / reception switching circuit 606.
Is entered.

The transmission / reception switching circuit 606 inputs a plurality of drive signals to a selector 608. The selector 608 selects a plurality of ultrasonic transducers forming a transmission aperture from the ultrasonic transducer array, and supplies a plurality of drive signals to them.

The plurality of ultrasonic transducers respectively generate a plurality of ultrasonic waves having a phase difference corresponding to a time difference between a plurality of drive signals. An ultrasonic beam is formed by wavefront synthesis of those ultrasonic waves. The transmission direction of the ultrasonic beam is determined by the transmission aperture selected by the selector 608.

The transmission of the ultrasonic beam is repeatedly performed at regular time intervals by the transmission timing signal generated by the transmission timing generation circuit 602. The transmission direction of the ultrasonic beam is sequentially changed by switching the transmission aperture by the selector 608. Thereby, the inside of the subject 4 is scanned by the sound ray formed by the ultrasonic beam. That is, the inside of the subject 4 is scanned in a sound ray sequence.

The selector 608 selects a plurality of ultrasonic transducers forming a receiving aperture from the array of ultrasonic transducers, and transmits a plurality of echo signals received by the ultrasonic transducers to the transmission / reception switching circuit 606. To be entered.

The transmission / reception switching circuit 606 inputs a plurality of echo signals to the reception beamformer 610. The receive beamformer 610 adds a time difference to the plurality of echo signals to adjust the phase, and then adds them to form a receive beamforming, that is, an echo receive signal on the receive sound ray. . Selector 6
By 08, the sound ray of the received wave is also scanned according to the transmitted wave.

The transmission timing generation circuit 602 to the reception beam former 610 are controlled by a control unit 18 described later. For example, scanning as shown in FIG. 3 is performed by the ultrasonic probe 2 and the transmitting / receiving unit 6. That is, as shown in FIG.
As the sound ray 202 emitted from 0 moves on the circular arc 204, the fan-shaped two-dimensional area 206 is scanned in the θ direction, and so-called convex scanning is performed. Sound ray 2
When 02 is extended in the direction opposite to the ultrasonic wave transmission direction (z direction), all sound rays intersect at one point 208. Point 208 is a divergence point of all sound rays.

The transmitting / receiving unit 6 is connected to a B mode (mode) processing unit 10 and a Doppler processing unit 12.
The echo reception signal for each sound ray output from the transmission / reception unit 6 is:
It is input to the B-mode processing unit 10 and the Doppler processing unit 12.

The B-mode processing unit 10 stores B-mode image data
(data). The B-mode processing unit 10
As shown in FIG. 4, four filters 100-1
06, and signal conditioners 110 to 116 connected to each filter.
Output signals of the reception beamformer 610 are input to the filters 100 to 106.

The filters 100 to 106 have frequency pass bands B1 to B4 shown in FIG. Band B1
Is adjusted to half the fundamental frequency f0 of the transmitted ultrasonic wave, that is, the subharmonic. Band B2 is
It is set to the fundamental frequency f0 of the transmitted ultrasonic wave. Band B4
Is adjusted to the second harmonic 2f0 of the transmitted ultrasonic wave. Band B3 matches the band between bands B2 and B4.
The filters 100 to 106 are controlled by a control unit 18 described later.

A signal conditioner (signal conditioner)
ner) 110 to 116 are filters 100 to 1 respectively.
06, logarithmic amplification, envelope detection,
Processing such as level adjustment and delay time adjustment is performed. Signal conditioners 110-116
Are controlled by the control unit 18 described later.

Signal conditioners 110 to 116
In each case, a signal representing the intensity of the echo at each reflection point on the sound ray, that is, an A-scope signal is obtained by logarithmic amplification and envelope detection, and the instantaneous amplitude of the A-scope signal is obtained. B mode (mode) as luminance value
Image data is formed. Thus, four systems of B-mode image data are obtained.

The level of the A scope signal can be adjusted by the level adjusting function of the signal conditioners 110 to 116. The delay amount can be adjusted by the delay time adjusting function.

The Doppler processing section 12 forms Doppler image data. The Doppler processing unit 12 includes a quadrature detection circuit 120 and an MTI filter (movin filter) as shown in FIG.
g target indication filter) 122, autocorrelation circuit 1
24, an average flow speed calculation circuit 126, a dispersion calculation circuit 128, and a power calculation circuit 130.

The Doppler processing unit 12 includes a quadrature detection circuit 12
0, the echo reception signal is subjected to quadrature detection, and the MTI filter 12
2, an autocorrelation circuit 124 performs an autocorrelation operation, an average flow velocity operation circuit 126 obtains an average flow velocity from the autocorrelation operation result, and a dispersion operation circuit 128 obtains a variance of the flow velocity from the autocorrelation operation result. The arithmetic circuit 130 obtains the power of the Doppler signal from the autocorrelation operation result.

As a result, each data (Doppler image data) representing the average flow velocity of the blood flow in the subject 4 and other Doppler signal sources (hereinafter referred to as blood flow, etc.) and its variance, and the power of the Doppler signal is converted into sound. Obtained line by line. The flow velocity is obtained as a component in the sound ray direction. The direction of the flow is distinguished between a direction approaching and a direction away from it.

The microballoon contrast agent 40 also becomes a Doppler signal source by the above-mentioned "scintillation". Therefore, it is possible to obtain Doppler image data for it.

The B-mode processing unit 10 and the Doppler processing unit 12 are connected to an image processing unit 14. The B-mode processing unit 10, the Doppler processing unit 12, and the image processing unit 14
5 is an example of an embodiment of an image generating unit according to the present invention. The image processing unit 14 generates a B-mode image and a Doppler image based on data input from the B-mode processing unit 10 and the Doppler processing unit 12, respectively.

As shown in FIG. 7, the image processing unit 14 includes a sound ray data memory (d) connected by a bus 140.
ata memory) 142, digital scan converter
(digital scan converter) 144, an image memory 146, and an image processor 148.

The B-mode image data and the Doppler image data input from the B-mode processing unit 10 and the Doppler processing unit 12 for each sound ray are stored in the sound ray data memory 142, respectively.

Digital Scan Converter 144
Is for converting data in a sound ray data space into data in a physical space by scan conversion. The image data converted by the digital scan converter 144 is stored in the image memory 146. That is, the image memory 1
Reference numeral 46 stores image data of the physical space. The image processor 148 performs predetermined data processing on the data in the sound ray data memory 142 and the image memory 146, respectively. The data processing will be described later.

The display section 16 is connected to the image processing section 14. The display unit 16 is provided with an image signal from the image processing unit 14 and displays an image based on the image signal. The display unit 16 is capable of displaying a color image.

The transmission / reception section 6, B-mode processing section 10,
Doppler processing unit 12, image processing unit 14, and display unit 16
Is connected to the control unit 18. The control unit 18 supplies a control signal to each unit to control its operation. Further, the control unit 18 is configured to receive various notification signals from the controlled units. Control unit 18
, The B-mode operation and the Doppler mode operation are performed.

An operation unit 20 is connected to the control unit 18. The operation unit 20 is operated by the operator, and the control unit 18
A desired command or information is input to the device. The operation unit 20 includes, for example, an operation panel provided with a keyboard and other operation tools.

(Operation) The operation of the present apparatus will be described. The operator injects the microballoon contrast agent 40 into the subject 4 in advance, abuts the ultrasonic probe 2 on a desired portion of the subject 4, operates the operation unit 20, and uses, for example, the B mode and the Doppler mode together. Imaging is performed.

Under the control of the control unit 18,
This is performed by a time-sharing operation between the mode and the Doppler mode.
That is, for example, a mixed scan of the B mode and the Doppler mode is performed at a rate of performing the B mode scan once every several times the Doppler mode scan is performed.

In the B mode, the transmission / reception unit 6 scans the inside of the subject 4 in the order of sound rays through the ultrasonic probe 2 and receives the echoes one by one. When the sound ray scans the injection site of the microballoon contrast agent 40, the echo includes
In addition to the fundamental echo from the body tissue, a second harmonic echo and evoked sound from the microballoon contrast agent 40 are included. Further, when the microballoon is destroyed, a subharmonics echo is also included. A signal in which these echoes are mixed is input from the transmission / reception unit 6 to the B-mode processing unit 10.

The B-mode processing unit 10 includes a filter 100,
At 102, 104 and 106, a sub-harmonics echo, a fundamental wave echo, an induced sound and a second harmonic echo are extracted, respectively.

At this time, the second harmonic echo, the subharmonics echo, and the induced sound are generated by a half cycle of the ultrasonic vibration or more than the fundamental wave echo by the echo generation mechanism of the micro balloon. Also, the narrow band characteristics of the filters 106 and 100 for extracting the second harmonic echo and the subharmonics echo, respectively, naturally increase the signal delay.

Since such a delay appears as a positional shift between the images when the images are formed, the delay time adjustment function of the signal conditioners 110 to 116 can be used.
The delay time of each signal is adjusted to eliminate the delay between them. Then, based on such signals, four types of B-mode image data corresponding to each echo are formed. The signal conditioners 110 to 116 are an example of an embodiment of the time difference adjusting means in the present invention.

The image processing section 14 stores the four types of B-mode image data input from the B-mode processing section 10 in the sound ray data memory 142. Thus, four lines of sound ray data space for B-mode image data are formed in the sound ray data memory 142.

In the Doppler mode, the transmission / reception unit 6 scans the inside of the subject 4 in the order of sound rays through the ultrasonic probe 2 and receives the echoes one by one. At this time, transmission of ultrasonic waves and reception of echoes are performed a plurality of times per sound ray.

The Doppler processing unit 12 performs quadrature detection on the echo reception signal by the quadrature detection circuit 120,
2, an autocorrelation circuit 124 obtains an autocorrelation, an average flow velocity operation circuit 126 obtains an average flow velocity, a variance operation circuit 128 obtains a variance, and a power operation circuit 130 obtains a power from the autocorrelation result.

These calculated values become Doppler image data representing, for each sound ray, the average flow velocity of the blood flow and the like, the variance thereof, and the power of the Doppler signal. Further, it becomes Doppler image data indicating “scintillation” of the microballoon contrast agent 40. The MTI filter 122
Is performed using a plurality of echo reception signals per sound ray.

The image processing unit 14 stores Doppler image data for each sound ray input from the Doppler processing unit 12 in the sound ray data memory 142. As a result, a sound ray data space for Doppler image data is formed in the sound ray data memory 142.

The image processor 148 converts the four B-mode image data and the Doppler image data in the sound ray data memory 142 into digital scan converters 144.
And scan-converted and written into the image memory 146.
At this time, the Doppler image data was converted to C
It is written as image data for an FM (color flow mapping) image and image data for a power Doppler image, respectively.

The image processor 148 has four B-systems.
Write the mode image, CFM image and power Doppler image in separate areas. The B-mode image based on the fundamental wave echo shows a tomographic image of the body tissue on the scanning plane. The B-mode image based on the second harmonic echo indicates the spread of the microballoon contrast agent 40 on the scanning plane. The B-mode image based on the induced sound and the B-mode image based on the subharmonics echo also indicate the spread of the microballoon contrast agent 40 on the scanning plane.

The B-mode image based on the second harmonic echo, the B-mode image based on the induced sound, and the B-mode image based on the subharmonics echo all show the image of the microballoon contrast agent 40. Due to the difference in the mechanism of occurrence of these, each of these B-mode images shows a unique mode. The difference in this aspect can be effectively used for pathological diagnosis and the like.

The CFM image is an image showing the two-dimensional distribution of the velocity of blood flow and the like on the scanning plane and the “scintillation” of the microballoon contrast agent 40. The power Doppler image is an image indicating blood flow and the like on the scanning plane and the location of “scintillation”. This “scintillation” also shows the image of the microballoon contrast agent 40 in a unique manner, and has utility from a viewpoint different from that of the B-mode image.

The operator operates the operation unit 20 to display various B-mode images or Doppler images on the display unit 16 as described above. That is, as shown in FIG. 8, for example, a combined image of the tomographic image 160 of the tissue and the second harmonic echo image 162 and a combined image of the tomographic image 160 of the tissue and the induced acoustic image 164 are arranged side by side on one screen. Display. This makes it possible to obtain contrast agent images each having a clear positional relationship with the tissue.

Since the delay time is adjusted by the signal conditioners 110 to 116, the images can be synthesized without displacement. Note that the adjustment of the positional deviation may be performed by the image processor 148 without necessarily adjusting the delay time in the signal conditioners 110 to 116. Here, the image processor 14
FIG. 8 shows an example of the embodiment of the time difference adjusting means in the present invention.

The tomographic image 160, the second harmonic echo image 162, and the induced acoustic image 164 of the tissue are preferably different in display color and the like from the viewpoint of facilitating discrimination. By comparing and contrasting such two display images, pathological diagnosis and the like can be effectively performed.

The induced acoustic image 164 can be replaced with a sub-harmonics echo image by designation. Also, CF
An M image or a power Doppler image can be used instead. Each of those images is also displayed in a unique color or the like. Alternatively, those images may be combined with the tomographic image 160 of the tissue, and all of them may be displayed side by side on the same screen, for example, as shown in FIG. This is preferable in that pathological diagnosis or the like using a comparative control is more effectively performed.

Alternatively, of the second harmonic echo image, the induced acoustic image, the subharmonics echo image, the CFM image and the power Doppler image, the control unit 18 or the image processor 148 has the highest signal level based on a predetermined evaluation criterion. An object may be selected and displayed so as to be superimposed on the fundamental wave echo image. This is preferable in that the clearest contrast agent image is displayed together with the tissue image.

When a mixture of soft and hard microballoon shells is used as the contrast agent, the soft balloon microballoon contrast agent image is mainly composed of the second harmonic echo image (non-destructive mode image). ), And the hard-shell microballoon contrast agent image is mainly obtained as a subharmonics echo image (destruction mode image). Therefore,
The mutual relationship between the two types of microballoons can be grasped from both images, and can be used for diagnosis.

By the way, in synthesizing a tomographic image of a tissue and a contrast agent image, simply adding them together requires
Even if the display colors are different, the contrast part is not always displayed clearly. Therefore, in a portion overlapping with the contrast agent image, fitting is performed instead of adding the images.

Hereinafter, the fitting of the contrast agent image will be described. In one mode of fitting the contrast agent image, the control unit 18
Is the second in the signal conditioner 116, for example.
The level of the harmonic echo signal is monitored, and when it exceeds a predetermined threshold, the level of the fundamental echo signal in the signal conditioner 112 is set to 0 or a very low level. Alternatively, the low-frequency cutoff (cut
off) The frequency is made higher than f0 to prevent the passage of the fundamental echo signal.

That is, the fundamental echo signal is modified based on the second harmonic echo signal. The signal conditioner 112 or the filter 102 and the control unit 18 are an example of an embodiment of a signal modifying unit according to the present invention.

As a result, the image data of the fundamental wave echo image becomes data of 0 or extremely low luminance in a portion overlapping with the second harmonic echo image, and the contrast agent image is embedded in that portion. 8, the display of the second harmonic echo image 162168 becomes clear.

By performing similar processing based on the induced acoustic signal and the sub-harmonics echo signal, the induced acoustic image 164 and the sub-harmonics echo image 166 can be fitted.

The above-described signal processing can also be performed by using the image processor 148. In other words, the data stored in the sound ray data memory 142 or the image memory 146 may be erased from the fundamental wave echo image portion corresponding to the portion where the contrast agent image data exceeds a predetermined threshold value. The effect can be obtained.

Also, the fitting of the contrast agent image 168 represented by the CFM image or the power Doppler image can be performed in the same manner. Here, the image processor 148 is an example of an embodiment of the signal modifying means in the present invention.

When processing is performed by the image processor 148, a so-called non-additive mixing method is used in which pixels of a contrast agent image and pixels of a tomographic image of a tissue are mixed without adding them. It is possible to obtain the same effect as fitting.

When the image is processed by the image processor 148, a tomographic image of the tissue overlapping the contrast agent image is separately cut out and displayed side by side with the composite image as shown in FIG. 10, for example. This is preferable in that the tissue image at the site where the contrast medium is lost can be seen.
This is also an embodiment of signal modification.

When the image processor 148 is used, a tissue image of a portion corresponding to a mask can be enhanced by using a contrast agent image as a mask. That is, of the data stored in the sound ray data memory 142 or the image memory 146, a portion where the contrast agent image data exceeds a predetermined threshold value is set as a mask region, and the luminance of the portion of the fundamental wave echo image corresponding to the mask region is increased. Alternatively, the luminance of a portion other than the mask region is reduced. This is also an embodiment of signal modification.

As a result, for example, as shown in FIG. 11, it is possible to obtain a tomographic image of the tissue in which the portion belonging to the mask region is emphasized, and to display an image in which the tomographic image of the tissue at the site where the contrast medium is injected is particularly emphasized. Can be. In emphasizing, it is preferable to apply emphasis according to the brightness of the contrast agent image in order to add an accent to the display image.

[0083]

As described above in detail, according to the present invention, an ultrasonic imaging method and apparatus for performing imaging by comprehensively utilizing a plurality of signals contained in ultrasonic waves returning from a microballoon contrast agent. Can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram of a device according to an example of an embodiment of the present invention.

FIG. 2 is a block diagram of a transmission / reception unit in the device according to an embodiment of the present invention;

FIG. 3 is a conceptual diagram of sound ray scanning performed by the apparatus according to the embodiment of the present invention;

FIG. 4 is a block diagram of a B-mode processing unit in the apparatus according to the embodiment of the present invention;

FIG. 5 is a graph showing a pass band of a filter in the device according to the embodiment of the present invention;

FIG. 6 is a block diagram of a Doppler processing unit in the apparatus according to the embodiment of the present invention;

FIG. 7 is a block diagram of an image processing unit in the apparatus according to the embodiment of the present invention;

FIG. 8 is a schematic diagram of a display image in the device according to an example of the embodiment of the present invention.

FIG. 9 is a schematic diagram of a display image in the device according to an example of the embodiment of the present invention.

FIG. 10 is a schematic diagram of a display image in the device according to an example of the embodiment of the present invention.

FIG. 11 is a schematic diagram of a display image in a device according to an example of an embodiment of the present invention.

[Explanation of symbols]

 2 Ultrasonic probe 4 Subject 40 Micro balloon contrast agent 6 Transmitter / receiver 10 B-mode processor 12 Doppler processor 14 Image processor 16 Display unit 18 Control unit 20 Operation unit 602 Transmission timing generation circuit 604 Transmission beamformer 606 Transmission / reception Switching circuit 608 Selector 610 Received beamformer 100-106 Filter 110-116 Signal conditioner 120 Quadrature detection circuit 122 MTI filter 124 Autocorrelation circuit 126 Average flow velocity operation circuit 128 Distributed operation circuit 130 Power operation circuit 140 Bus 142 Sound ray data memory 144 Digital scan converter 146 Image memory 148 Image processor 200 Radiation point 202 Sound ray 204 Arc 206 Two-dimensional area 208 Divergence point

Claims (6)

[Claims] 1. An ultrasonic imaging method for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium is injected and generating an image based on an echo of the ultrasonic wave, wherein a frequency band of a fundamental wave of the transmitted ultrasonic wave is provided. An ultrasonic imaging method characterized in that the echo of (1) and the echoes of frequency bands on both sides thereof are used for image generation, respectively. 2. An ultrasonic imaging method for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium is injected and generating an image based on an echo of the ultrasonic wave, wherein a frequency band of a fundamental wave of the transmitted ultrasonic wave is provided. And an echo in a frequency band outside of the received signal and a signal modification between the received signals or signals based on the received signals. 3. An ultrasonic imaging method for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium has been injected and generating an image based on an echo of the ultrasonic wave, wherein a frequency band of a fundamental wave of the transmitted ultrasonic wave is provided. And receiving the echoes in the frequency band outside the echo and the time difference between the received signals. 4. A transmission / reception means for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium is injected, and receiving an echo in a frequency band of a fundamental wave of the transmitted ultrasonic wave and an echo in a frequency band on both sides thereof, An ultrasonic imaging apparatus comprising: an image generation unit configured to generate an image based on a plurality of echo signals having different frequency bands received by the transmission / reception unit. 5. A transmission / reception means for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium has been injected, and receiving an echo in a frequency band of a fundamental wave of the transmitted ultrasonic wave and an echo in a frequency band outside the same, respectively; A plurality of echo signals having different frequency bands received by the transmitting / receiving means or a signal modifying means for performing signal modification between signals based on the echo signals; and an image generating means for generating an image based on the signal after the signal modification. An ultrasonic imaging apparatus comprising: 6. A transmitting / receiving means for transmitting an ultrasonic wave to a subject into which a microballoon contrast medium has been injected, and receiving an echo in a frequency band of a fundamental wave of the transmitted ultrasonic wave and an echo in a frequency band outside the ultrasonic wave, respectively, The transmission / reception unit includes a time difference adjustment unit that adjusts a time difference between a plurality of echo signals having different frequency bands, and an image generation unit that generates an image based on the signal whose time difference has been adjusted by the time difference adjustment unit. An ultrasonic imaging apparatus characterized by the above-mentioned.