JP2001061841A - Ultrasonograph, and method of producing ultrasonic image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide tomographic images of the same scanned part both in the THI(Tissue Harmonic Imaging) mode and in the regular B mode by imaging under the most suitable transmission condition for either mode. SOLUTION: This ultrasonograph has transmitting/receiving means 21, 13, 22, and 23 for transmitting ultrasonic pulses under the most suitable condition of transmission/receiving for the regular B mode and for the THI(Tissue Harmonic Imaging) mode respectively to the same part of a subject to receive the echo signals in each mode. The apparatus also has tomographic image producing means 24, 25 and 29 for producing tomographic images in the regular B mode and in the THI mode based on the echo signals and display means 26-28 for displaying the tomographic images in the regular B mode and in the THI mode at the same time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus capable of obtaining a tomographic image based on an ultrasonic echo signal reflected from an organ or tissue and observing the shape, dynamics or properties of the organ or tissue from the tomographic image. And a method for generating an ultrasonic image.
In particular, the harmonic imaging method (Harmoni
c Tissue Harmonic Imaging (Tissue Harmonic; HI)
ic Imaging (THI) and normal B-mode imaging individually under optimal transmission conditions, and / or an ultrasonic diagnostic apparatus and a generation of an ultrasonic image having a function of simultaneously providing tomographic images of both imagings About the method.

[0002]

2. Description of the Related Art Ultrasound diagnostic apparatuses that obtain image signals by transmitting and receiving ultrasonic signals to and from a subject have been conventionally used in various modes by utilizing the non-invasiveness of ultrasonic signals.

[0003] The mainstream of this ultrasonic diagnostic apparatus is of a type in which a tomographic image of a soft tissue of a living body is obtained using an ultrasonic pulse reflection method. This imaging method is non-invasive and obtains a tomographic image of the tissue, and can be displayed in real time compared to other medical modalities such as X-ray diagnostic equipment, X-ray CT scanner, MRI equipment, and nuclear medicine diagnostic equipment, The apparatus has many advantages, such as a small and relatively inexpensive apparatus, no exposure to X-rays, and the ability to perform blood flow imaging based on the ultrasonic Doppler method. Therefore, it is suitable for diagnosis of the heart, abdomen, breast line, urology, obstetrics and gynecology, and the like. In particular, simple operations such as applying an ultrasonic probe to the body surface enable real-time observation of heartbeats and fetal movements. There is also an advantage that the inspection can be easily performed by moving the inspection tool.

[0004] There are various imaging methods based on the ultrasonic pulse reflection method, and one of them is an imaging method which has been particularly spotlighted in recent years. This is a method called a harmonic imaging (HI) method, which is currently roughly classified into two types.

[0005] One is an imaging method which is a further development of the contrast echo method performed by administering an ultrasonic contrast agent, and which is a method for more effectively detecting a signal derived from the contrast agent (hereinafter referred to as contrast harmonic. This is called an imaging method). Microbubbles, the main component of the contrast agent,
It has stronger acoustic nonlinearity than a living organ, and generates more harmonic components (non-fundamental components). Therefore, the contrast harmonic imaging method detects a non-linear component with respect to a transmission fundamental frequency, particularly a reflected echo signal of a second harmonic (harmonics) component, and attempts to differentiate a signal level from an organ that does not easily generate harmonics. It is based on things. For example, since the reflected echo signal contains the fundamental frequency component of the transmitted pulse wave and the harmonic component caused by the contrast agent, extracting only these harmonic components from the echo signal makes it possible to use the contrast agent (microbubbles) for the echo signal of the living organ. The signal ratio of the echo signal is significantly improved, and an image reflecting the harmonic component, that is, the degree of enhancement caused by the contrast agent is obtained.

[0006] Thus, the contrast harmonic
By using an imaging method, the presence or absence of a contrast agent in a region of interest, that is, blood flow perfusion can be observed by administering a relatively small amount of a contrast agent, and useful information for diagnosis can be obtained.

The other is a harmonic component caused by the waveform of the ultrasonic pulse being distorted while the ultrasonic pulse propagates through a living organ (hereinafter, this harmonic component is referred to as a non-fundamental component in a broad sense). Is used to extract and image only tissue harmonic imaging (TH)
I) method (for example, JP-A-10-17958)
No. 9). Naturally, it is known that the absolute value of the intensity of the echo signal is smaller than the fundamental component (the center frequency of the transmitted ultrasonic pulse) by the harmonic component by -20 dB or more. Although the use of the harmonic component having a small signal strength requires high-sensitivity signal processing, the imaging by the THI method has the following advantages.

(1) First, in the case of the THI method, the signal of the harmonic component is not directly transmitted from the vibrator, but is generated only when the transmitted ultrasonic pulse propagates a proper distance from the vibrator. You. Therefore, multiple echoes from an obstacle located immediately below the transducer (for example, a rib when scanning a circulatory region from between the ribs) are significantly reduced.

(2) Further, since higher harmonic components are generated more in a portion where the sound pressure is high, the beam in the focal direction (ie, main lobe) is emphasized, and conversely, the side lobe is further reduced. As a result, a sound field beam profile with better directivity is formed.

Therefore, by using the THI method, noise due to multiple reflections and side lobe artifacts is formed, so that the image quality is improved. Specifically, the contrast ratio of the border and parenchyma of the organ is improved, while
Better “looseness” of heart chambers and gallbladder.

Further, in the harmonic imaging method including the THI method, the following two methods are currently mainly used as methods for extracting a harmonic component from an echo signal.

(1) One is a method called a filter method, in which an echo signal is filtered by a high-pass filter. For example, when the transmission frequency is 2 MHz, the echo signal is 4M
It is filtered by a filter that passes only a band above Hz.

(2) Another method is disclosed in, for example,
This is a method called a pulse inversion method (PI method) proposed in Japanese Patent Application Publication No. 164138. According to this method, the ultrasonic pulse whose polarity is inverted is transmitted respectively (that is, transmitted twice to one raster), and the echo signals associated with the two transmissions are added. This allows
Since the component of the linear echo signal is canceled and only the non-linear component remains, the B-mode process using the non-linear signal component as a luminance signal is performed to obtain a tomographic image.

[0014]

SUMMARY OF THE INVENTION As described above, TH
The I method has various advantages over the normal B mode imaging method, but does not surpass the normal B mode method in all aspects. (Note that in the THI method, with respect to processing of an echo signal (a part of it: a harmonic component) into a luminance signal of a tomographic image, a conventional method of converting an entire echo signal into a luminance signal, which is conventionally performed, is used.
It can be equated with the mode method). Therefore, this conventional normal B-mode method is referred to as “normal B-mode method (or normal B-mode imaging method)” and is distinguished from the THI method (THI mode). For example, assuming that the transmission frequencies are the same, TH
Since the frequency of the echo signal received by the I method is normally twice that of the B mode method (when the THI method uses the second harmonic), the amount of attenuation due to the living body is also doubled. The imageable depth decreases. Further, since the signal intensity of the harmonic component is low as described above, it is difficult for some patients to propagate sound waves, and as a result, the image quality of the THI method may be lower than that of the normal B mode.

One of the solutions that can be easily conceived in view of such a situation is to equip a mechanism for switching modes. The conventional ultrasonic diagnostic apparatus is provided with a mode switching button in a very ordinary manner, and by operating this button, it is possible to instruct switching between various imaging modes such as the B mode and the Doppler mode. ing. The switching instruction means using the mode switching button is also applied to mode switching between the normal B mode and the THI mode. Thus, diagnosis may be performed while switching between the normal B mode and the THI mode.

However, the imaging by this switching cannot normally observe both images of the B mode and the THI mode at the same time. Since both modes have both advantages and disadvantages, the desire to simultaneously display tomographic images of both modes at the same time naturally appears on the same screen in order to simultaneously obtain the best points of both modes. It is. However, the above-described switching method cannot meet such needs.

If so, normal B mode and TH
As a method of simultaneously imaging both I-mode tomographic images, a circuit configuration is conceivable in which a transmission pulse signal is commonly used and the echo signal is processed in two ways for each mode. That is, the same echo signal is filtered by a harmonic filter on the one hand to generate a THI mode echo signal, and on the other hand, it is used as it is as a normal B mode echo signal. Thereby, tomographic images of both modes are obtained at the same time.

However, optimum transmission conditions (transmission sound pressure, transmission frequency, transmission rate, probe transmission aperture, transmission focus, etc.) in the THI mode and the normal B mode are different. Therefore, the above-described circuit configuration in which a transmission pulse signal is shared does not enable imaging in an optimal transmission state in both modes. If the transmission condition is set to an optimal condition for one mode, the other mode must accept deterioration of the transmission condition. Therefore, the circuit configuration described above is not a circuit configuration in which the diagnostic utility can be fully exhibited in both modes.

The present invention has been made in view of the current situation of the above-described conventional THI mode and normal B mode itself, and the inconvenience of the imaging method easily conceived from existing imaging methods. Normally, imaging is performed under the optimal transmission conditions for each B mode, and tomographic images of the same scan area in both modes are simultaneously provided, thereby fully utilizing the advantages of both modes and improving the tissue shape and dynamics. A first object is to enable accurate diagnosis and to enrich the information amount of the diagnosis.

Further, according to the present invention, tomographic images of the normal B mode and the THI mode of the same scan site are simultaneously presented on the same screen, and either one of the images is selected and observed, or both images are compared. It is a second object of the present invention to facilitate appropriate observation such as observation.

[0021]

In order to achieve the above object, one category of the present invention is provided as an ultrasonic diagnostic apparatus.

In order to achieve the first object, according to one aspect of the present invention, transmission / reception conditions including a transmission condition optimal for a normal B mode and an optimal condition for a THI (tissue harmonic imaging) mode are set in the same part of a subject. Transmission / reception means for individually transmitting ultrasonic pulses to obtain respective echo signals under the transmission / reception conditions including various transmission conditions, and the normal B mode and THI based on the echo signals obtained by the transmission / reception means. An ultrasonic diagnostic apparatus is provided, comprising: generating means for generating a tomographic image in a mode; and display means for simultaneously displaying the tomographic images in the normal B mode and the THI mode.

As a result, imaging is performed under optimal transmission conditions for the THI mode and the normal B mode, and tomographic images of the same scan site in both modes are simultaneously displayed. Therefore, the advantages of both modes are fully exhibited, and the tissue shape and dynamics can be more accurately diagnosed.

The above configuration can be further developed in various modes.
As an example, the transmission / reception unit transmits an ultrasonic pulse to the subject under transmission / reception conditions including a transmission condition optimal for a normal B mode to obtain an echo signal thereof,
A second transmission / reception unit that transmits an ultrasonic pulse to the subject under transmission / reception conditions including a transmission condition optimal for the THI mode and obtains an echo signal thereof.

Further, the first transmitting / receiving means includes first transmitting means for transmitting an ultrasonic pulse according to an optimum transmission condition for the normal B mode, and an echo signal responsive to the transmission of the ultrasonic pulse to the normal B mode. A first receiving unit for receiving in the B mode, the second transmitting / receiving unit includes: a second transmitting unit for transmitting an ultrasonic pulse according to an optimal transmission condition for the THI mode; Receiving the echo signal in response to the transmission in the THI mode,
May be provided.

Further, for example, the display means is means for simultaneously displaying the tomographic images in the normal B mode and the THI mode on the same screen on the same monitor.

Preferably, the optimal transmission condition for the THI mode is smaller than the optimal transmission condition for the normal B mode.
This is a condition that satisfies at least one of the following items: lower transmission frequency, lower transmission wave number, lower level driving voltage, and lower driving element number.

More preferably, the transmission and reception under the transmission and reception conditions optimal for the normal B mode and the transmission and reception under the transmission and reception conditions optimal for the THI mode are switched for each raster by the ultrasonic pulse. A transmission / reception control unit to be executed may be provided. For example, the transmission / reception control means causes the transmission / reception under the transmission / reception conditions optimal for each mode to be executed at least once for each raster. Further, for example, the transmission / reception control unit causes the transmission / reception under the transmission / reception conditions optimal for both modes to be repeatedly and alternately performed for each raster.

More preferably, the transmission and reception under the optimum transmission and reception conditions for the normal B mode and the transmission and reception under the optimum transmission and reception conditions for the THI mode are switched and executed for each image frame. The control means is provided.
In this case, the transmission / reception control means may cause the transmission / reception under the transmission / reception conditions optimal for the both modes to be repeatedly and alternately executed for each frame. Further, the transmission / reception control means may cause the transmission / reception under the transmission / reception conditions optimal for the both modes to be continuously performed for at least one mode for a plurality of frames. further,
It is preferable that the display means is means for simultaneously displaying the tomographic images in the normal B mode and the THI mode on the same screen of the same monitor.

On the other hand, in order to achieve the second object,
According to another aspect of the present invention, transmitting and receiving means for transmitting an ultrasonic pulse to a subject for each raster and receiving an echo signal, and transmitting means for separately transmitting ultrasonic pulses before and after polarity inversion to the subject for each raster And receiving means for receiving echo signals of the ultrasonic pulse before and after polarity inversion, respectively.
Adding means for mutually adding the echo signals of the ultrasonic pulse before and after the polarity inversion received by the receiving means, and each of the echo signals based on the echo signal added by the adding means and the echo signal received from the transmitting / receiving means. There is provided an ultrasonic diagnostic apparatus including: a generating unit that generates a plurality of types of tomographic images; and a display unit that simultaneously displays the plurality of types of tomographic images.

According to another aspect of the present invention, there is provided a transmitting means for separately transmitting ultrasonic pulses before and after polarity reversal to a subject for each raster, and the ultrasonic means before and after polarity reversal. Receiving means for receiving the echo signal of the sound pulse, an adding means for mutually adding the echo signals of the ultrasonic pulse before and after the polarity inversion received by the receiving means, and an echo signal added by the adding means Generating means for generating a plurality of tomographic images based on at least one of the echo signals of the ultrasonic pulse before and after the polarity inversion received from the receiving means, and display means for simultaneously displaying the plurality of tomographic images. There is provided an ultrasonic diagnostic apparatus comprising:

In order to further achieve the second object,
According to another invention of the present application, transmitting means for transmitting ultrasonic pulses before and after polarity inversion to the subject separately for each raster, and receiving means for receiving echo signals of the ultrasonic pulse before and after polarity inversion, respectively, Multiplying means for multiplying any one of the echo signals of the ultrasonic pulse before and after the polarity inversion received by the receiving means by an adjustable gain as a weighting coefficient; and an echo signal output by the multiplying means and the receiving means Adding means for mutually adding the other of the echo signals of the ultrasonic pulse before and after the polarity reversal received by the adding means, generating means for generating a tomographic image based on the echo signal added by the adding means, There is provided an ultrasonic diagnostic apparatus comprising: display means for displaying an image.

Preferably, the receiving means is means for receiving the echo signal according to a tissue harmonic imaging (THI) method. For example, the receiving means may include a filter means for passing a non-fundamental wave component of the frequency of the ultrasonic pulse.

By using the apparatus using the pulse inversion method, the normal B mode and the TH
I-mode tomographic images are simultaneously presented on the same screen. Therefore, observation can be easily performed in an appropriate mode, such as selecting and observing one of the images or observing while comparing both images.

Further, in order to achieve the above object, another category of the present invention is provided as a method for generating an ultrasonic image.

Specifically, in order to achieve the first object,
According to another aspect of the present invention, the same part of the subject, usually B
Under the transmission / reception conditions including the transmission conditions optimal for the mode and the transmission / reception conditions including the transmission conditions optimal for the THI (tissue harmonic imaging) mode, the ultrasonic pulses are individually transmitted and their echo signals are individually received. An ultrasonic image generating method for generating the normal B mode and THI mode tomographic images based on the echo signals and displaying the normal B mode and THI mode tomographic images simultaneously. .

Further, in order to achieve the second object, according to another invention of the present application, ultrasonic pulses before and after polarity reversal are individually transmitted to the subject for each raster, and the ultrasonic pulses before and after the polarity reversal are transmitted. Each of the echo signals is received, and the received echo signals of the ultrasonic pulse before and after the polarity inversion are added to each other, and at least the added echo signal and the echo signal of the ultrasonic pulse before and after the received polarity inversion are received. There is provided a method for generating an ultrasonic image, wherein a plurality of types of tomographic images are generated based on one of them, and the plurality of types of tomographic images are simultaneously displayed.

Further, in order to achieve the second object, according to another invention of the present application, ultrasonic pulses before and after the polarity inversion are individually transmitted to the subject for each raster, and the ultrasonic pulses before and after the polarity inversion are transmitted. Each of the echo signals is received, and any one of the echo signals of the ultrasonic pulse before and after the polarity inversion is multiplied by an adjustable gain as a weighting factor, and the multiplied echo signal is received. An ultrasonic image generation method, characterized in that the ultrasonic wave echo signals before and after the polarity inversion are mutually added to each other, and a tomographic image is generated and displayed based on the added echo signals. Is done.

[0039]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.
This will be described with reference to the accompanying drawings.

<First Embodiment> The first embodiment is
This will be described with reference to FIGS. The ultrasonic diagnostic apparatus according to this embodiment is configured as an apparatus having a function of identifying abnormal parts by obtaining information on the dynamics and shape of the heart, for example, but is not necessarily limited thereto. Instead, the apparatus may be used for diagnosis of other organs or substantial parts.

The ultrasonic diagnostic apparatus shown in FIG. 1 has an apparatus main body 11 functioning as a control center of the whole system, an electrocardiograph (ECG) 12 connected to the apparatus main body 11, an ultrasonic probe 13, and an operation unit. 14. The operation unit 14 gives various instructions and information from the operator to the apparatus main body 11. In addition to the operation unit main body 14M, a keyboard 14A, a mouse 14B for setting an ROI (region of interest), a trackball 14C. And a mode changeover switch 14D for manually switching the diagnostic mode. In particular, the switch position “normal B” for instructing “scan using both normal B mode and THI mode” in one imaging is set as the switch position by the mode changeover switch 14D.
Mode + THI mode ".

The ultrasonic probe 13 has a piezoelectric vibrator such as a piezoelectric ceramic as an electro / mechanical reversible conversion element. A plurality of piezoelectric vibrators are arranged in an array and provided at the tip of the probe, and a phased array type probe 13 is configured. As a result, the probe 13 converts the pulse drive voltage given from the apparatus main body 11 into an ultrasonic pulse signal and transmits the ultrasonic pulse signal in a desired direction in the subject, and on the other hand, converts the ultrasonic echo signal reflected in the subject into an ultrasonic echo signal. The signal is converted into an echo signal having a voltage corresponding to this.

The apparatus main body 11 includes a probe 13 as shown in FIG.
Transmitting unit 21 and receiving unit 2 connected to
2. Digital filter 23, receiver unit 24, DSC (digital scan converter) unit 25, memory synthesis unit 26, D /
An A converter 27 and a display 28 are provided. DSC unit 25
Is connected to an image memory 29.

The apparatus main body 11 further includes an amplifier 31 and a reference data memory 32 which are sequentially connected to the output side of the electrocardiograph 12. The apparatus main body 11 further includes a CPU (central processing unit) 41 that receives operation data from the operation unit 14, and further includes a trigger signal generator 42 and a timing signal generator 43 that play a role of a control center.

The ultrasonic transmitter 21 includes a pulse generator 51,
It has a transmission delay circuit 52, an electronic switching type switch 53, and a normal B mode pulser 54B and a THI mode pulser 54H.

The pulse generator 51 generates a rate pulse having a rate frequency fr [Hz] of 5 kHz (period: 1 / fr [second]), for example. The rate pulses are distributed to the number of transmission channels and sent to the transmission delay circuit 52. The transmission delay circuit 52 is supplied with a timing signal for determining a delay time from the timing signal generator 43 for each transmission channel. Thereby, the transmission delay circuit 5
2 assigns a command delay time to the rate pulse for each channel.

Switch 53 provided in ultrasonic transmission unit 21
Switches the electronic output path alternatively according to a switching signal sent from the timing signal generator 43. One switching terminal “1” of the switch 53 is connected to a normal B-mode pulser 54B, and the other switching terminal “2” is connected to a THI mode pulse 54H. By the alternate switching operation of the switch 53, the rate pulse to which the delay time is given is output to the normal B mode pulser 54B or the THI mode pulser 54H for each transmission channel.
Supplied to

The normal B-mode pulser 54B applies a drive voltage pulse to the vibrator of the probe 13 for each channel at the timing of the rate pulse received via the switch 53. By this excitation, ultrasonic signals are transmitted from the plurality of piezoelectric vibrators of the ultrasonic probe 13 toward the subject,
Beamforming (phasing addition) is performed in the commanded raster direction in the subject according to the delay time pattern. At the time of transmission in the THI mode, the switch 53 is switched to the switching terminal "2" side, and the THI mode pulser 54H operates in the same manner.

A driving voltage pulse in the normal B mode (normal transmission pulse) and a driving voltage pulse in the THI mode (transmission pulse for THI) relating to the two pulsers 54B and 54H.
The waveform parameters are set in advance so that the optimum ultrasonic transmission can be performed in each mode. The number of driving elements used by the ultrasonic probe 13 is also set to be optimal for each mode. In the present embodiment, transmission conditions are formed by the waveform parameters and the number of driving elements.

FIGS. 2 and 3 show examples of setting transmission conditions. Here, a transmission frequency, a transmission wave number, a drive voltage, and a drive element number are adopted as transmission conditions, and these values are set to optimal values for each mode. Note that these transmission conditions may be recorded in each pulser as a fixed value for each mode, or may be configured to be switchable according to a command from the CPU 41.

First, the transmission frequency is 5 in the normal B mode.
The frequency is set to a relatively high frequency of MHz, while the THI mode is set to a low value of 2.5 MHz (the receiving frequency in this case is, for example, 5 MHz). This is THI
When the same 5 MHz transmission frequency as in the normal B mode is used in the mode, the frequency of the echo signal is 10 MHz.
This is because the value becomes extremely high (at the time of the second harmonic), and when the heart or the liver is set as the region of interest, the attenuation effect is too large and is not suitable for diagnosis.

Next, regarding the number of transmission waves, the number of transmission pulses in the normal B mode is set to one, and the pulse length is shortened to increase the resolution. On the other hand, in the THI mode, two waves are set, and the frequency characteristics have a certain narrow-band characteristic. 3A and 3B show the relationship between the pulse length (wave number) and the frequency band for each mode.

Regarding the drive voltage (transmission voltage), THI
In the mode, a voltage as high as 100 V, for example, is applied to the vibrator and transmitted in order to more effectively extract a nonlinear phenomenon in which the transmitted ultrasonic pulse is distorted. Although there is no particular limitation on this point in the normal B mode, since the total power per unit time of the ultrasonic pulse transmitted into the living body is limited, TH
In order to relatively increase the maximum allowable voltage in the I mode, the transmission voltage in the normal B mode is reduced (for example, 60 V).

Regarding the number of driving elements, for the same reason as the driving voltage described above, when the number of driving elements in the THI mode is set to 80, for example, that in the normal B mode is set to 60, for example.
And set less.

Note that the transmission focus and the transmission rate may be added to the above-described optimal transmission conditions for each mode. For example, the transmission focus is set at the center in the depth direction in the normal B mode, and is set at the depth portion in the depth direction in the TMI mode, with more emphasis on the sensitivity in the deep part. For the transmission rate, for example, TM
The rate of the I mode is set smaller than that of the normal B mode. Note that the control of these transmission conditions may be performed alone or in combination of two or more.

In this embodiment, the normal B-mode pulser 5
Transmission via 4B is referred to as "normal transmission", and transmission via the THI mode pulser 54H is referred to as "THI transmission".

The ultrasonic transmission unit 2 shown in FIG.
Instead of the circuit configuration of FIG. 1, one shown in FIG. 4 may be employed. This uses a waveform generator 55 and a class-A operation type amplifier 56 instead of the normal mode and THI mode pulsers and switches. Waveform generator 55 is CP
A pulse having an arbitrary waveform can be generated in response to a control signal supplied from U41. For example, a pulse having a lower harmonic component than a normal rectangular wave, such as a Sinc waveform, can be generated for each transmission channel. Therefore, for example, a pulse having a different transmission frequency and / or number of transmission waves for each mode can be supplied to the class-A operation amplifier 56 using a Sinc waveform pulse for each transmission channel. The class-A operation type amplifier 56 voltage-amplifies the applied pulse under the class-A operation to generate drive voltage pulses for each transmission channel, and supplies them to the probe 13. Therefore, as in the case of the circuit configuration of FIG. 1, ultrasonic transmission can be performed under optimal transmission conditions for the normal B mode and the THI mode.

On the other hand, the ultrasonic pulse signal transmitted from the ultrasonic probe 13 is reflected on the discontinuous surface of the acoustic impedance in the subject. This reflected ultrasonic signal is received again by the probe 13 and converted into an echo signal of a corresponding voltage amount. This echo signal is output from the probe 13 for each reception channel, and is taken into the ultrasonic receiving unit 22.

The ultrasonic receiver 22 includes a preamplifier 61, an A / D converter 62, and a reception beam former 63 in this order from the input side. The preamplifier 61 and the A / D converter 62 each include an amplifier circuit or an A / D conversion element for the reception channel. Receive beamformer 63
Includes a reception delay circuit having a delay element provided for each reception channel, and an adder for adding their delay outputs. The delay time pattern of the reception delay circuit is provided from the timing signal generator 43 as a trigger signal pattern in accordance with a desired reception directivity. For this reason, the echo signal is amplified by the preamplifier 61 for each channel, and A / A
The data is A / D converted by the D converter 62 and sent to the beam former 63. In this beamformer 63, a delay time is given to digital echo data and added.
As a result, a reflection component from a direction corresponding to a desired reception directivity is emphasized. By combining the transmission directivity and the reception directivity, an overall ultrasonic beam for transmission and reception is formed.

The output end of the beam former 63 reaches the receiver 24 via the digital filter 23 described above.
The filtering coefficient of the digital filter 23 is controlled by the coefficient controller 30, and the signal pass band can be changed according to the coefficient control state. The coefficient controller 30 performs the above-described coefficient control in response to the timing signal from the timing signal generator 43 and the coefficient control signal from the CPU 41.

More specifically, in the case of the normal B mode, the digital filter 23 is band-controlled so as to pass the signal as it is, or is band-controlled so as to be a band-pass filter for the transmission frequency. (This reception state is called “normal reception”). On the other hand, in the THI mode, the band is controlled so as to be a high-pass or band-pass filter that passes only a nonlinear component (for example, a second harmonic component) required for the THI method (at this time, The reception state is called “THI reception”).

On the other hand, although not shown, the receiver section 25 receiving the filtered echo data includes a digital type logarithmic amplifier and an envelope detector. Thereby, the echo data of the normal B mode and the THI mode is converted into a luminance signal and sent to the DSC unit 25. DS
The C unit 25 converts the scan system of the echo data from the ultrasonic system to the standard TV system, and sends it to the memory synthesis unit 26. At the same time, the echo data output by the DSC unit 25 is stored in the frame memory 29 in frame units.

On the other hand, the electrocardiogram signal detected by the electrocardiograph (ECG) 12 is supplied to a reference data memory 32 via an amplifier 31.
Sent to The reference data memory 32 generates reference data such as an electrocardiogram waveform corresponding to the electrocardiogram signal, and sends the reference data to the memory synthesis unit 26.

The memory synthesizing unit 26 has the normal B mode and the T mode.
The image in the HI mode is reconstructed, and the image data and the reference data in both modes are combined with the image data of one frame according to the display mode control signal sent from the CPU 41. The image data in frame units is sequentially read out by the display unit 28 via the D / A converter 27 and displayed on the TV monitor. As will be described later, a typical mode of combining image data in both modes is to arrange or superimpose both image data. As a result, the spatial distribution of the tissue shape of the subject at the same time (timing) is simultaneously displayed almost in real time on the same screen as a normal B-mode and THI-mode tomographic image.

The CPU 41 always executes a predetermined main program, and when the operation unit 14 instructs a scan for automatic mode switching using both the normal B mode and the THI mode (that is, the mode switching switch 14D). Is set to the "normal B mode + THI mode"), the processing shown in FIG. 5 is performed in response to this. As a result, as described later, the normal reception is performed during the normal transmission via the timing signal generator 43.
At the time of THI transmission, THI reception is automatically set.

The CPU 41 also controls the trackball 14
When a ROI setting signal is received from C or the like, the ROI
The graphic data relating to the (region of interest) is sent to the memory synthesis unit 26, and a process of superimposing the graphic data on the display image is performed. Further, the CPU 41 operates the display unit 28 from the keyboard 14A or the like.
When the display mode of the TV monitor is instructed, a signal for instructing the display mode is sent to the memory synthesis unit 26. Further, the CPU 41 controls the setting of a filter coefficient value for the coefficient controller 30.

The timing signal generator 43 includes a CPU 41
The transmission delay circuit 5 transmits a transmission / reception delay time pattern signal relating to scanning in the normal mode and the THI mode, a switching signal of the transmission unit, and a switching timing signal between the two modes of the filter coefficient based on the command from
2. Send them to the receive beamformer 63, the switch 53, and the coefficient controller 30, respectively. By switching between normal transmission and THI transmission by this timing control,
In synchronization with this, switching between normal reception and THI reception is performed.

Next, a scan executed by the CPU 41 in which the normal B mode and the THI mode are used together in the same imaging will be described.

The CPU 41 has a mode changeover switch 14D
Is set to "normal B mode + THI mode", the process of FIG. 5 is started in response to this.

Now, it is assumed that the scanning method of the electronic sector system is adopted. This scanning method is raster (scanning line)
The ultrasonic waves are transmitted and received in sequence for each raster while changing the direction (angle) of. For example, it is generated with 120 rasters.

The CPU 41 starts the processing of FIG. 5 in response to a command from the operation unit 14. Assuming that a parameter indicating a raster position is n and a parameter indicating a scan number is m, in step S1 of FIG.
Initialized to 0.

Next, in step S2, n = n + 1 and m = m + 1 are incremented. This allows
An initial position where the raster position is n = 1 is calculated, and the scan number m = 1 is counted. Thereafter, step S3
, A harmonic transmission and a harmonic reception are instructed to the timing signal generator 43. The scan in the THI mode with the raster position n = 1 and the scan number m = 1 is performed prior to the normal B mode at the same raster position (see FIG. 6).

That is, the switch 53 of the ultrasonic transmitter 21
The coefficient controller 30 on the receiving side is switched in synchronization with the THI mode side. As a result, T
The HI mode pulser 54H can operate, and the band of the digital filter 23 is switched to the THI mode on the receiving side. Therefore, transmission and reception in the THI mode are performed, and echo data relating to the spatial distribution of the tissue or organ of the subject is obtained from the receiver unit 25.

Next, the CPU 41 sets a step S.
Steps S4 and S5 are sequentially performed. In step S4,
Only the scan number m is incremented by m = m + 1. In step S5, the timing signal generator 43
For normal transmission and normal reception. The switch 53 of the ultrasonic transmission unit 21 and the coefficient controller 30 on the receiving side are switched in synchronization with the normal B mode. Normal B with raster position n = 1 and scan number m = 2
The scan in the mode is performed at the same raster position following the THI mode (see FIG. 6).

As a result, the normal B-mode pulser 54B can operate on the transmitting side, and the band of the digital filter 23 is switched to the normal B-mode on the receiving side. Therefore, transmission and reception in the normal B mode are performed, and echo data relating to the spatial distribution of the tissue shape of the subject is obtained from the receiver unit 25.

Next, the CPU 41 proceeds to step S6.
The processing is shifted to the raster position n = n _max(Otherwise 12
0) or scan number m = m_max
(For example, 240 = 120 × 2)
Then, it is determined whether or not to end the scan control. This judgment
If the answer is NO, the process returns to step S2 again, and
A series of processing is repeated.

With the above-described scan control, two transmissions and receptions, one in the THI mode and the other in the normal B mode, are performed for each raster in the same direction, as shown in FIGS. The rasters are sequentially switched, and transmission and reception in the two modes are performed for each raster. As a result,
One scan of normal B-mode image data and one THI mode image data are generated by 240 scans.
The time difference between data collection on the same raster is "1 / fr" seconds, and high real-time performance is maintained.

Echo data obtained by alternately scanning in the two modes passes through the DSC unit 25 and is stored in the memory synthesizing unit 2.
6 sequentially. In the memory synthesizing unit 26, the image data in the normal B mode and the image data in the THI mode, which are alternately sent almost in real time, are sorted by mode. At the same time, the image data of both modes is combined into one frame in accordance with the display mode specified at that time, and displayed on the TV monitor of the display unit 28 almost in real time.

FIG. 8 shows an example of this display. The figure shows
Image _{IM norma l} image IM with THI mode (tomographic image representing the spatial distribution of tissue shape) of the normal B-mode
_{harmon ics} (tomographic image representing the spatial distribution of tissue shape)
Are divided and displayed side by side in one screen.

According to the display example shown in FIG. 8, both the normal B mode image and the THI mode image are displayed in the same size, but the image sizes do not necessarily have to be the same.
In the present invention, it is important that images in both modes transmitted and received at the same timing are simultaneously displayed on the same screen, and there is no limitation on the image size, and the sizes of the two images may be different from each other. . For example, it is preferable that the image in the normal B mode is displayed in a size of 1/4 of the THI mode and displayed in the upper right of the screen.

As described above, on the screen of the display unit 28, two types of tomographic images of the normal B mode and the THI mode, which are obtained by scanning the same scan area at substantially the same time, are displayed almost in real time.

In the tomographic images displayed in these two modes, transmission conditions (transmission frequency, transmission wave number, drive voltage, drive element number, etc.) unique to each mode when transmitting an ultrasonic pulse are set. ing. Therefore, in both the tomographic images in both modes, it is possible to provide a tomographic image of a tissue morphology or organ shape having the best image quality in a given environment in terms of resolution and artifact. That is, it is possible to always provide two types of tomographic images that fully demonstrate the superiority of each mode.
Further, a switching operation between the two modes is not required.

By providing two types of tomographic images at the same time as described above, first, there is a usefulness that a diagnosis can be performed by making use of the features and advantages of each mode.

On the other hand, in the THI mode tomographic image, since multiple echoes at a short distance from the body surface are reduced, the image quality of the short distance portion (for example, when the heart is to be scanned, the image of the myocardial front wall portion) is reduced. improves. In addition, since the directivity of the ultrasonic beam is improved by reducing the side lobe, the heart chamber (in the case of the abdomen, a site of low echo such as the gallbladder)
Is improved in contrast (good omission).

On the other hand, according to the tomographic image in the normal B mode, the beam penetration is excellent, and the morphological observation of a deeper part can be easily performed.

Further, there is a usefulness that a diagnosis can be made by selecting the superior one of the two types of tomographic images or using them complementarily.

That is, when there is a difference in the composition frequency characteristics of the tissue, the difference in the contrast ratio may change between the images in both modes. For example, when a tumor such as a liver cancer exists in the liver parenchyma, the contrast between the parenchyma and the tumor has different frequency characteristics. For example, in a normal B-mode tomographic image, there is no difference in luminance between a parenchyma part and a tumor part (that is, it is difficult to visually distinguish), whereas in a THI-mode tomographic image, a luminance difference occurs in an echo, and it is visually distinguished Easily. The opposite situation may occur for some subjects.

Therefore, if the tomographic images of both modes are displayed on the same screen, the tomographic image of the mode in which the lesion is visually clearer (the degree of differentiation is large) can be quickly determined. It is possible to make a reliable diagnosis. In addition, not only when the degree of visual differentiation does not change so much between the two-mode tomographic images, but also when the degree of such discrimination is large, the tomographic images of both modes are mutually referred to, and the lesion area Can confirm each other's shape and the like, which can contribute to improvement in the reliability of diagnosis.

The following various modifications of the first embodiment described above are also possible.

First, according to one modification, as an additional function of the first embodiment, a function of selectively performing a scan in the normal mode or the THI mode may be provided. Normal mode and THI are set to the mode switch 14D.
It is sufficient to provide a switch position for individually designating the mode scan, and the CPU 41 detects this and forcibly instructs the timing signal generator 43 to select one of the modes (the normal mode or the THI mode).

Another modification relates to changing the scan order for both modes. In the first embodiment, when a scan using both the normal B mode and the THI mode is executed, the scan in the THI mode and the scan in the normal B mode are alternately performed for each raster. Are obtained together. The present modification aims to diversify the scan order.

Basically, one frame of scan (for example, 120 scans) is performed collectively by sequentially changing the direction of the raster for each mode, and when one frame of one mode has been scanned, another scan is performed. Shift to scan in one mode. However, various modifications are possible regarding the number of images and the combination order for each mode. For example, as shown in FIG. 8, scanning in both modes may be performed alternately for each frame. For example, as shown in FIG. 9, when an image for one frame in the THI mode is obtained, then an image for three frames in the normal B mode is obtained, and this is repeated. As a result, the frame rate of each mode can be changed, and a function of increasing the frame rate of one mode can be added to the apparatus if tissue dynamics is to be preferentially observed in one mode.

<Second Embodiment> A second embodiment will be described with reference to FIGS. The ultrasonic diagnostic apparatus according to this embodiment performs the above-described “scan using both the normal B mode and the THI mode” by pulse inversion (P
The method is characterized in that it is carried out according to the method I) and simultaneously provides tomographic images in the normal B mode and the THI mode in one imaging. In this case, the transmission condition may be set to an optimal state for the THI mode, and the THI mode may be prioritized over the normal B mode for optimal transmission conditions.

FIG. 10 shows an ultrasonic diagnostic apparatus according to this embodiment.
As shown in FIG. 1, the circuit shown in FIG. 1 is used, and a circuit for performing the pulse inversion method is added thereto. Specifically, the mode changeover switch 14D includes, in the switch position in the first embodiment, a switch position for commanding “scan using both the normal B mode and the THI mode” based on the PI method. The CPU 41 responds to the switch operation to the switch position by using the timing signal 4.
3 and the memory synthesizing unit 26 can be instructed to perform such a scan.

In the receiving system, a digital type adding circuit 61 is interposed between the digital filter 23 and the receiver section 24. The addition circuit 61 is connected to a line memory 62 having a read / write control unit.

When the “scan using both the normal B mode and the THI mode” based on the PI method is instructed, the control signal from the timing signal generator 43 causes the aforementioned THI
Switching to transmission and THI reception. In this switching state, for example, the ultrasonic pulse is transmitted twice on the same raster in the same manner as in the transmission and reception order of FIG. 6 described above. At this time, as shown in FIG. 11, the polarity of the pulse B of the second transmission is inverted by 180 degrees with respect to the pulse A of the first transmission.

The echo signals A 'and B' are received in response to the transmission of the ultrasonic pulses A and B, and the echo signals are processed in the same manner as in the first embodiment, and added as digital signals. The circuit 61 is entered. The adder circuit 61 once records the first echo signal A 'in the line memory 62 and
Wait for the second echo signal. The adder circuit 61 calls the first echo signal A 'from the line memory 62 in synchronization with the input of the second echo signal B', and adds both of them to form one raster as schematically shown in FIG. To generate an echo signal C ′. In the echo signal C ′, a linear echo component is canceled and a harmonic component remains based on the principle of the PI method (for example, see Japanese Patent Application Laid-Open No. 9-164138). As described above, the added signal C ′, most of which is only harmonic components, is then sent to the receiver unit 24.

As schematically shown in FIG. 12, the adder circuit 61 allows any one of the two input echo signals A 'and B', for example, the echo signal A 'to pass through without being added. , To the receiver 24 prior to the addition signal C ′.

Therefore, the echo signal A not added is
Is processed as an echo signal for the normal B mode, and the added signal C 'is processed by the receiver unit 24 as an echo signal for the THI mode, and sent to the memory synthesis unit 26. As a result, as in the first embodiment, the normal B-mode tomographic image based on the echo signal A 'not added and the THI-mode tomographic image based on the added signal C' are displayed on the screen of the display unit 28. Displayed side by side.

Therefore, according to the present embodiment, the normal B
Although the transmission conditions used for obtaining the tomographic image in the mode are those of the THI mode, the tomographic images in both the normal B mode and the THI mode can be displayed on the same screen at a relatively high frame rate. Therefore, it is possible to observe a lesion by appropriately utilizing both images, such as referring to a normal B-mode tomographic image while mainly using a THI-mode tomographic image. Since the tomographic images of both modes are presented at the same time, there is no need to switch the mode each time, and the operation and diagnosis are greatly reduced.

Also, as in the first embodiment, since the THI mode tomographic image obtained by the pulse inversion method is based on a harmonic signal, multiple echoes at a short distance from the body surface are reduced. In addition, the quality of an image at a short distance (in the heart, an image near the front wall of the heart muscle) is improved. Furthermore, since the directivity of the ultrasonic beam is good, the contrast (good omission) of the heart chamber (a part of low echo such as the gallbladder in the case of the abdomen) is improved.
On the other hand, the tomographic image in the normal B mode is generated by giving the transmission / reception conditions to the THI mode. However, the penetration is relatively good, and the observation of the deep form is easy. Can be covered.

As a modification of the second embodiment, a configuration in which the second embodiment is combined with the above-described first embodiment can be adopted.

For example, three ultrasonic transmission / reception operations may be performed for each raster. Of these, during the first and second transmission / reception, the addition circuit 61 and the line memory 62 according to the second embodiment are used, and the T method using the PI method is used.
An HI mode tomographic image is obtained. However, in this case, the echo signal A ′ (see FIG. 12) that passes through the addition circuit 61 as it is is not generated, and only the addition signal C ′ is obtained.
At the time of the third transmission / reception, normal transmission and normal reception are performed, and the echo signal passes through the addition circuit 61 without addition. As a result, while a THI mode tomographic image is obtained with the THI mode transmission condition set to the optimum value, imaging is also performed in the normal B mode under the optimum transmission condition. Thereby, in addition to the operation and effect of the second embodiment, there is also obtained an advantage that the image quality of the normal B-mode tomographic image is improved.

<Third Embodiment> A third embodiment will be described.
This will be described with reference to FIG. The ultrasonic diagnostic apparatus according to this embodiment executes the “scan using both the normal B mode and the THI mode” based on the pulse inversion (PI) method and superimposes the tomographic images of the normal B mode and the THI mode. Is displayed.

The first embodiment described above is based on the fact that the tomographic images in the normal B mode and the THI mode are displayed side by side on the same screen and are simultaneously displayed (see FIG. 7). On the other hand, in the configuration of the second embodiment, a configuration in which tomographic images of both modes are superimposed and displayed is also possible. This will be described as a third embodiment.

As shown in FIG. 13, the adder circuit 61 shown in FIG. 10 includes a variable gain multiplier 70 in the path of the echo signal B 'for the second transmission and reception, and multiplies the echo signal B' by a gain as a weighting coefficient. It is supposed to. In addition,
The multiplier may be inserted in the path of the first transmitted / received echo signal A '. The multiplier 70 may be configured to perform a multiplication function by software processing, or may use a hardware multiplication circuit. The gain of the multiplier 70 can be manually adjusted by an operator. Through the gain adjustment, a value such as a weighting coefficient of 0.8 is multiplied to the echo signal B ′.

For this reason, the levels of the fundamental wave components when adding the echo signals A 'and B' based on the two transmissions / receptions are made different from each other, so that the fundamental wave component remains in the added echo signal C '. . This echo signal C 'is equivalent to the echo signal A' and C 'shown in FIG. The display unit 28 displays the echo signal C
', One type of tomographic image is displayed. This tomographic image is an image obtained by superimposing both tomographic images in the normal B mode and the THI mode.

The superimposed images of both modes generated in this way have the advantages of compensating for the disadvantages of the modes, having a high resolution and being able to image deep. At this time, since the weighting coefficient can be adjusted by changing the gain of the multiplier, it is possible to prevent a situation in which the effects of the modes are canceled each other, and it is possible to appropriately secure the advantages of both modes.

Note that the ultrasonic diagnostic apparatus according to the present invention is not limited to the configuration described in the above-described embodiment and its modifications, and those skilled in the art will appreciate that the ultrasonic diagnostic apparatus described in the claims can be used. It is needless to say that various modifications can be made according to the purpose.

[0110]

As described above, according to the present invention,
Imaging is performed under optimal transmission conditions for the THI mode and the normal B mode, and tomographic images of the same scan site in both modes are provided at the same time. Can be diagnosed more accurately, and the amount of diagnostic information can be enriched.

Further, according to the present invention, tomographic images of the normal B mode and the THI mode of the same scan area are simultaneously presented almost in real time on the same screen, and either one of the images is selected and observed. Observation in an appropriate mode such as observation while comparing images can be easily performed.

[Brief description of the drawings]

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

FIG. 2 is a diagram illustrating an example of transmission conditions in a normal B mode and a THI mode.

FIG. 3 is a diagram for explaining a relationship between a wave number and a frequency band for each mode.

FIG. 4 is a schematic block diagram showing another example of the ultrasonic transmission unit.

FIG. 5 is a schematic flowchart for controlling the transmission / reception order in scanning using both the normal B mode and the THI mode.

FIG. 6 is a diagram showing an example of the order of transmission and reception within one frame in scanning using both the normal B mode and the THI mode.

FIG. 7: Normal B simultaneously displayed on the screen of the same monitor
The figure which shows the example of a display mode of the tomographic image of mode and THI mode.

FIG. 8 is a diagram showing a modification of the transmission / reception order (transmission / reception order for each frame) in scanning using both the normal B mode and the THI mode.

FIG. 9 is a diagram showing another modification of the transmission / reception order (transmission / reception order for each frame) in scanning using both the normal B mode and the THI mode.

FIG. 10 is a schematic block diagram illustrating an overall configuration of an ultrasonic diagnostic apparatus according to a second embodiment of the present invention.

FIG. 11 is a diagram illustrating a pulse for polarity determination according to the pulse inversion method.

FIG. 12 is a schematic diagram illustrating an addition operation based on a pulse inversion method according to the second embodiment.

FIG. 13 is a schematic diagram illustrating an addition operation based on a pulse inversion method according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 Device main body 13 Ultrasonic probe (transmission means, reception means, transmission / reception means, 1st and 2nd transmission means, 1st and 2nd reception means) 14 operation unit 14D mode changeover switch 21 ultrasonic transmission part (transmission means) , Transmitting / receiving means, first and second transmitting means) 22 ultrasonic receiving section (receiving means, transmitting / receiving means, first and second receiving means) 23 digital filter (receiving means, transmitting / receiving means, first
And second receiving unit) 24 receiver unit (generating unit) 25 DSC (generating unit) 26 memory combining unit (display unit) 27 D / A converter (display unit) 28 display unit (display unit) 29 image memory 30 coefficient Controller (transmission / reception control means) 41 CPU (transmission / reception control means) 42 Trigger signal generator (transmission / reception control means) 43 Timing signal generator (transmission / reception control means) 53 Switch (transmission / reception control means) 54B Pulser for normal B mode 54H For THI mode Pulser 61 Addition circuit (addition means) 62 Line memory (addition means) 70 Multiplier (multiplication means)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4C301 AA02 CC01 CC02 DD06 DD07 EE11 EE20 FF28 GB02 HH01 HH02 HH04 HH07 HH17 HH38 HH52 JB03 JB04 JB11 JB29 JB32 JB36 JB38 JB42 JC14 KK13 KK30 LL02 LL02LL04LL

Claims (20)

[Claims] 1. An ultrasonic pulse is transmitted to the same part of a subject under transmission / reception conditions including transmission conditions optimal for normal B mode and transmission / reception conditions including transmission conditions optimal for THI (tissue harmonic imaging) mode. Transmitting / receiving means for individually transmitting and separately obtaining their echo signals; generating means for generating the normal B mode and THI mode tomographic images based on the echo signals obtained by the transmitting / receiving means; An ultrasonic diagnostic apparatus comprising: display means for simultaneously displaying a THI mode tomographic image. 2. The ultrasonic diagnostic apparatus according to claim 1, wherein the transmission / reception unit transmits an ultrasonic pulse to the subject under transmission / reception conditions including a transmission condition optimal for a normal B mode, and transmits an echo signal thereof. A first transmitting / receiving unit for obtaining an ultrasonic pulse to the subject under the transmitting / receiving conditions including a transmitting condition optimal for the THI mode to obtain an echo signal thereof. Ultrasound diagnostic device. 3. The ultrasonic diagnostic apparatus according to claim 2, wherein the first transmitting / receiving unit transmits an ultrasonic pulse according to an optimal transmission condition for the normal B mode, and the ultrasonic transmitting unit transmits the ultrasonic pulse. A first receiving unit that receives the echo signal in response to the transmission of the pulse in the normal B mode, and the second transmitting / receiving unit transmits an ultrasonic pulse according to an optimal transmission condition for the THI mode. An ultrasonic diagnostic apparatus comprising: a second transmitting unit; and a second receiving unit that receives an echo signal in response to the transmission of the ultrasonic pulse in the THI mode. 4. The ultrasonic diagnostic apparatus according to claim 1, wherein the display unit displays the tomographic images in the normal B mode and the THI mode on the same screen of the same monitor at the same time. An ultrasonic diagnostic apparatus, which is a means. 5. The ultrasonic diagnostic apparatus according to claim 1, wherein an optimal transmission condition for the THI mode is lower than an optimal transmission condition for the normal B mode. An ultrasonic diagnostic apparatus, characterized in that the condition satisfies at least one item among a frequency, a smaller number of transmission waves, a lower level driving voltage, and a smaller number of driving elements. 6. The ultrasonic diagnostic apparatus according to claim 1, wherein the transmission / reception under the optimal transmission / reception conditions for the normal B mode and the transmission / reception conditions optimal for the THI mode are performed. An ultrasonic diagnostic apparatus comprising transmission / reception control means for switching and executing the transmission and reception in each raster by the ultrasonic pulse. 7. The ultrasonic diagnostic apparatus according to claim 6, wherein the transmission / reception control means performs at least one transmission / reception of each raster under transmission / reception conditions optimal for each mode.
An ultrasonic diagnostic apparatus characterized by being executed twice. 8. The ultrasonic diagnostic apparatus according to claim 7, wherein said transmission / reception control means causes said transmission / reception under optimum transmission / reception conditions for both modes to be repeatedly and alternately executed for each raster. Ultrasound diagnostic equipment. 9. The ultrasonic diagnostic apparatus according to claim 1, wherein the transmission / reception under the optimal transmission / reception conditions for the normal B mode and the transmission / reception conditions optimal for the THI mode are performed. An ultrasonic diagnostic apparatus comprising transmission / reception control means for switching between the transmission and reception in each of the frames for execution. 10. The ultrasonic diagnostic apparatus according to claim 9, wherein said transmission / reception control means causes said transmission / reception under optimal transmission / reception conditions for both modes to be repeatedly and alternately executed for each frame. Ultrasound diagnostic equipment. 11. The ultrasonic diagnostic apparatus according to claim 9, wherein the transmission / reception control means continuously performs the transmission / reception under the transmission / reception conditions optimal for the both modes for at least one mode for a plurality of frames. An ultrasonic diagnostic apparatus characterized by being executed by: 12. The ultrasonic diagnostic apparatus according to claim 9, wherein the display unit simultaneously displays the normal B mode and THI mode tomographic images on the same screen of the same monitor. An ultrasonic diagnostic apparatus, which is a means. 13. A transmitting / receiving means for transmitting an ultrasonic pulse to a subject for each raster and receiving an echo signal, and a transmitting means for separately transmitting ultrasonic pulses before and after polarity inversion to the subject for each raster. Receiving means for receiving echo signals of the ultrasonic pulse before and after the polarity inversion, respectively, adding means for mutually adding the echo signals of the ultrasonic pulse before and after the polarity inversion received by the receiving means, and this adding means Generating means for respectively generating a plurality of tomographic images based on the added echo signal and the echo signal received from the transmitting / receiving means, and display means for simultaneously displaying the plurality of tomographic images. Ultrasound diagnostic device characterized by the following. 14. A transmitting means for individually transmitting ultrasonic pulses before and after polarity inversion to a subject for each raster, a receiving means for receiving echo signals of the ultrasonic pulses before and after polarity inversion, respectively, and the receiving means. Adding means for mutually adding the echo signals of the ultrasonic pulse before and after the polarity inversion received, and the echo signal added by the adding means and the echo of the ultrasonic pulse before and after the polarity inversion received by the receiving means An ultrasonic diagnostic apparatus comprising: generating means for generating a plurality of types of tomographic images based on at least one of signals; and display means for simultaneously displaying the plurality of types of tomographic images. 15. A transmitting means for individually transmitting ultrasonic pulses before and after polarity reversal to a subject for each raster, a receiving means for receiving echo signals of the ultrasonic pulses before and after polarity reversal, and the receiving means. Multiplying means for multiplying any one of the echo signals of the ultrasonic pulse before and after the received polarity inversion by an adjustable gain as a weighting coefficient; and an echo signal output by the multiplying means and received by the receiving means. Adding means for mutually adding the other of the echo signals of the ultrasonic pulse before and after the polarity inversion, generating means for generating a tomographic image based on the echo signal added by the adding means, and displaying the tomographic image An ultrasonic diagnostic apparatus comprising: a display unit. 16. The ultrasonic diagnostic apparatus according to claim 13, wherein said receiving means is means for receiving said echo signal according to a tissue harmonic imaging (THI) method. Ultrasonic diagnostic equipment. 17. The ultrasonic diagnostic apparatus according to claim 16, wherein said receiving means includes a filter means for passing a non-fundamental wave component of the frequency of said ultrasonic pulse. . 18. An ultrasonic pulse is transmitted to the same part of the subject under the transmission and reception conditions including the transmission conditions optimal for the normal B mode and the transmission and reception conditions including the transmission conditions optimal for the THI (tissue harmonic imaging) mode. Separately transmitting and receiving their echo signals separately, generating the tomographic images of the normal B mode and the THI mode based on the echo signals, and displaying the tomographic images of the normal B mode and the THI mode simultaneously A method for generating an ultrasonic image, comprising: 19. An ultrasonic pulse before and after the polarity inversion is transmitted to the subject separately for each raster, and an echo signal of the ultrasonic pulse before and after the polarity inversion is received, and the received ultrasonic pulse before and after the polarity inversion is received. The echo signals of the ultrasonic pulse are added to each other, and a plurality of types of tomographic images are generated based on the added echo signal and at least one of the received echo signals of the ultrasonic pulse before and after the polarity inversion. A method for generating an ultrasonic image, wherein a tomographic image of a subject is displayed simultaneously. 20. Transmitting ultrasonic pulses before and after the polarity inversion to the subject for each raster, receiving echo signals of the ultrasonic pulses before and after the polarity inversion, respectively, and receiving the echo signals before and after the received polarity inversion. Multiply any one of the echo signals of the ultrasonic pulse by an adjustable gain as a weighting coefficient, and multiply the echo signal subjected to this multiplication and the other of the echo signals of the ultrasonic pulse before and after the received polarity inversion. A method for generating an ultrasonic image, wherein the ultrasonic signals are added to each other, and a tomographic image is generated and displayed based on the added echo signals.