JP2002224114A - Ultrasonic diagnostic instrument and ultrasonic diagnostic method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and accurately describe data expressing the pulsation properties of a blood flow and to allow an operator to certainly discriminate the kind of a blood vessel. SOLUTION: In an ultrasonic diagnostic instrument, scanning means (1-3, 7 and 4A) perform repeatedly first scanning for obtaining a first receiving signal while transmitting ultrasonic pulses plural times in a first direction along a scanning cross section while moving the first direction, and repeatedly second scanning for obtaining a second receiving signal while transmitting ultrasonic pulses plural times in a second direction different from the first direction while moving the second direction, substantially these operations in parallel. An extraction means (4B) extracts a Doppler signal of a blood flow from the first and second receiving signals at every sample point. Processing means (4C-4F) obtain the two-dimensional distribution image data of the acceleration of a blood flow on the basis of the blood flow Doppler signal corresponding to the first and second scanning. A display means (6) displays the two-dimensional distribution image data of the acceleration of the blood flow.

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 and an ultrasonic diagnostic method for displaying the dynamics of moving elements such as blood flow and moving tissue in a subject, and more particularly, to the pulsation of blood flow. The present invention relates to an ultrasonic diagnostic apparatus and an ultrasonic diagnostic method capable of reliably capturing a change in gender and movement of a tissue and displaying the change with high accuracy.

[0002]

2. Description of the Related Art In recent years, an ultrasonic diagnostic apparatus used at a medical site has many imaging modes according to the purpose of diagnosis. The imaging mode includes, for example, a B mode for displaying a tomographic image and a CFM (Color) for displaying a blood flow image.
Flow Mapping mode, TDI (Tissue Doppler I) for displaying the velocity image of tissue
(Mag.) mode.

[0003] Among these imaging modes, the CFM mode displays blood flow information of two-dimensional mapping in real time, and normally displays a flow approaching the ultrasonic probe in red and a flow away from the probe in blue. Let me.

In order to perform the display in the CFM mode, as is conventionally widely known, the same position (scanning line direction) in the subject is scanned a plurality of times (N times) by ultrasonic waves. In addition, the velocity of the blood cell at each depth position is detected from the time-series echo signals collected at each depth position based on the Doppler method. That is, the Doppler signal is a reflection signal (blood flow signal) from blood cells obtained by scanning the same place at predetermined time intervals.
Is obtained from the phase shift amount (Doppler shift amount) within the unit time of the above, and this phase shift amount is converted into the blood flow velocity.

[0005] Echo signals associated with each ultrasonic scan include:
A reflected wave from a moving object such as a blood cell and a reflected wave from a fixed object that hardly moves such as a blood vessel wall or an organ are mixed. What is characteristic is that the latter is dominant in terms of the reflection intensity, and the former has a Doppler shift, while the latter has almost no Doppler shift (fixed reflectors). The reflected wave from is called a clutter signal). Therefore, a Doppler signal is extracted from the echo signal by quadrature phase detection (comprising a mixer and a low-pass filter (LPF)). The Doppler signal is sent to the MTI filter, and the clutter component of the Doppler signal is removed by the MTI filter using the difference in the Doppler shift amount. In this way, a blood flow Doppler signal composed of N pieces of Doppler data is efficiently extracted at each depth position.

[0006] The blood flow Doppler signal is subjected to frequency analysis to determine an average frequency (Doppler frequency) of the spectrum and to calculate a variance value or a reflection intensity (power) from blood cells. The Doppler frequency f _d is

(Equation 1) It can be converted to the Doppler velocity V _d based on the expression. Here, c is the sound velocity, the f _M reference signal frequency of the mixer, theta is the angle between the ultrasound beam and the blood flow (called Doppler angle).

Normally, the Doppler angle differs for each sample position sampled in a space defined by a cross section of a subject (scanned cross section) scanned by ultrasonic waves. However, the per sample position seeking Doppler angle for calculating the Doppler velocity V _d by the equation (1), practically with the computing power, it is difficult. For this reason, conventionally, a simplified arithmetic expression without correction of the Doppler angle is used.

[Number 2] _{V d = f d · c /} (2f M) on the basis of ... (2) Doppler velocity _{V d} is computed.

[0008] computing the Doppler velocity V _d on the basis of the equation (2) may be a velocity of blood flow is actually flowing is the same, the more Doppler angle position greater, to be a slower speed Means. This phenomenon is called angle dependence.

[0009] The (2) the blood flow information of each sample location in the resulting scan section on the basis of the equation, i.e. Doppler velocity V _d is typically monitored on a CFM image of the two-dimensional distribution which is superimposed on the B-mode image Will be displayed.

On the other hand, in the TDI mode, the movement of a tissue such as a myocardium is two-dimensionally displayed in real time.
Also in the TDI mode, the movement of the tissue approaching the ultrasonic probe is normally displayed in red, and the movement of the tissue moving away from the probe is displayed in blue.

In order to perform the display in the TDI mode, as in the case of the above-mentioned CFM mode, the same scanning line direction of the scanning section is ultrasonically scanned a plurality of times at predetermined time intervals, and the reflected signal from the tissue is reflected. (Tissue echo signal) is collected.
The tissue Doppler signal is directly obtained from the phase shift amount (Doppler shift amount) of the reflected signal within a unit time. The tissue Doppler signal in the same manner as described above, is converted into a tissue motion velocity V _d using said without Doppler angle correction (2). Thus tissue motion velocity V _d of each sample position on the obtained scan cross section is typically displayed on a monitor as a TDI image of the two-dimensional distribution is superimposed on the B-mode image.

The CFM mode is a display method for grasping the dynamics of the blood flow from the movement speed based on the blood flow Doppler signal. On the other hand, attempts have been made to make it possible to observe the dynamics of blood flow from acceleration information. As an example, Japanese Patent Publication No. 2768959 (Japanese Patent Application No. 63-3161)
No. 17), based on the blood flow velocities of two consecutive frames written in the frame memory and the time interval between the frames in which these blood flow velocities are detected, the motion acceleration of the blood flow. Is calculated, and the motion acceleration is displayed two-dimensionally.

[0013]

In recent years, with the progress of diagnostic methods, there is a demand for a display method capable of easily and accurately distinguishing blood vessels such as arteries, portal veins, and veins. One way to distinguish the type of blood vessel as described above using ultrasound is to focus on the pulsatility of blood flow.

One method of observing the pulsatility in the conventional CFM mode speed display is to watch the temporal change of the color indicating the speed value. Specifically, if the color indicating the speed value changes over time, it indicates pulsatility, and if it does not change, it indicates a non-pulsatile state. It should be possible.

However, in practice, it is often difficult to discriminate even if the user is gazing at the speed display image, which is not practical. For example, the blood flow velocity, which indicates the pulsation of an artery, rapidly rises and falls during 200 to 300 ms corresponding to the contraction of the heart, and thereafter gradually decreases. For this reason, it is desired that the rapid rise and fall be reliably captured and displayed with high accuracy.However, in the case of the speed display, such a change in the movement cannot always be reliably captured, and the change information may be missed. I was Therefore, there has been a demand for a display method that can more easily identify the pulsatility according to the type of blood vessel.

In addition, as described above, in the case of the CMF mode, the problem of angle dependence is neglected.

In the method of displaying an acceleration distribution image, which is one of the conventional methods described above, the blood flow velocity for two frames, that is, the calculation is performed between frames, so that the calculation is performed at coarse time intervals. I have. For this reason, it is highly likely that satisfactory performance is not necessarily obtained, such as a lack of time resolution for a blood flow that moves violently in a short time period such as the above-mentioned systole of the heart.

On the other hand, in the case of the TDI mode, for example, the state of myocardial movement can be observed, and studies have been made to improve the diagnostic ability of heart diseases. At present, only the speed of tissue movement is considered, but further progress is expected by providing a mode for accurately displaying other parameters useful for tissue movement. However, in the case of the TDI mode, too, since the motion velocity of the tissue obtained by the Doppler method is displayed, the ability to capture a change in the motion is insufficient, particularly when displaying the motion dynamics accompanying the pulsation of the myocardium. .
At the same time, the above-described problem of angle dependence remains.

The present invention has been made in view of the above-mentioned problems of the prior art, and can easily and accurately depict information representing the pulsatility of blood flow, thereby enabling the operator to know the type of blood vessel. An object of the present invention is to provide an ultrasonic diagnostic apparatus capable of making a reliable determination.

Further, the present invention provides an ultrasonic diagnostic apparatus capable of delineating the motion state of a tissue with a two-dimensional distribution image based on a new parameter with high accuracy and accurately reflecting the motion state. , With another purpose.

[0021]

In order to achieve the above object, the ultrasonic diagnostic apparatus according to the present invention can take various forms.

The basic configuration will be described. According to one of the basic configurations, an ultrasonic diagnostic apparatus according to the present invention is an apparatus that transmits an ultrasonic pulse to a subject and scans a desired cross section of the subject, as described in claim 1. A first scan in which the ultrasonic pulse is transmitted a plurality of times in the first direction along the cross section and a scan for obtaining a first reception signal for each transmission is repeated by moving the first direction, and
While transmitting the ultrasonic pulse a plurality of times in a second direction along the cross section different from the first direction, a scan for obtaining a second reception signal for each transmission is moved in the second direction. Scanning means for performing a repetitive second scan substantially in parallel, and first and second motion element signals representing the state of motion of the motion element in the cross section from each of the first and second received signals Extraction means for extracting each of the sample points of the cross section, processing means for obtaining two-dimensional distribution image data of acceleration representing the state of movement of the motion element based on the first and second motion element signals, And a display means for displaying the two-dimensional distribution image data.

According to another basic configuration, an ultrasonic diagnostic apparatus according to the present invention transmits an ultrasonic pulse to a subject to scan a desired cross section of the subject. And transmitting the ultrasonic pulse in the first direction along the cross section a plurality of times, and
A first scan that repeats the scan for obtaining the received signal by moving the first direction, and transmitting the ultrasonic pulse a plurality of times in a second direction along the cross section different from the first direction. Scanning means for performing a scan for obtaining a second reception signal for each transmission while moving in the second direction and repeating the second scan substantially in parallel, and the first and second reception signals. And processing means for obtaining two-dimensional distribution image data of the acceleration representing the state of movement of the motion element in the cross section, and display means for displaying the two-dimensional distribution image data of the acceleration.

Further, according to another basic configuration, a first aspect is provided.
In the ultrasonic diagnostic apparatus according to the first or second aspect, preferably, as described in the third aspect, the scanning unit performs the first and second scans on each of the scan lines on the cross section based on the ultrasonic pulse. A scan control unit is provided which causes one of the two scans to follow the other scan with a certain time difference.

Further, according to another basic configuration, an ultrasonic diagnostic apparatus according to the present invention transmits an ultrasonic pulse to a subject to scan a desired cross section of the subject. Scanning means for obtaining a reception signal for the transmission, speed calculation means for calculating the speed of movement of the motion element existing on the cross section from the reception signal, and calculating the acceleration of the movement of the motion element using the speed. An ultrasonic diagnostic apparatus comprising: an acceleration calculating unit; wherein the speed calculating unit includes a turn-back removing unit that removes an influence of the speed turning phenomenon.

Further, according to another basic configuration, an ultrasonic diagnostic apparatus according to the present invention transmits an ultrasonic pulse to a subject to scan a desired cross section of the subject. A first scan for transmitting a plurality of ultrasonic pulses in a first direction along the cross-section and obtaining a first reception signal for each transmission by moving the first direction in the first direction. And scanning the second direction along the cross section different from the first direction to obtain a second reception signal for each transmission while transmitting the ultrasonic pulse a plurality of times in the second direction along the cross section. Scanning means for performing a second scan that is repeated in a substantially parallel manner, wherein the transmission of the ultrasonic pulse in the first direction based on the first scan and the second scan are performed. The ultrasonic path in a second direction; The time difference from the transmission of a scan line to the time required for scanning one scanning line based on the ultrasonic pulse to the time required for scanning a plurality of scanning lines one less than the plurality of scanning lines for one frame. A desired time difference between the two.

Further, according to the present invention, while transmitting an ultrasonic pulse a plurality of times in a first direction along a section to be imaged in a subject, a first reception is performed for each transmission. A first scan for repeating a scan for obtaining a signal by moving the first direction, and transmitting the ultrasonic pulse a plurality of times in a second direction along the cross section different from the first direction. A scan for obtaining a second received signal for each transmission is performed substantially in parallel with a second scan that is repeated while moving in the second direction, and the cross section is obtained from each of the first and second received signals. The first and second motion element signals representing the motion state of the motion element in are extracted for each sample point of the cross section, and the motion state of the motion element is represented based on the first and second motion element signals. Find two-dimensional distribution image data of acceleration The ultrasonic diagnostic method for displaying a two-dimensional distribution image data of the acceleration, it is characterized is provided.

Further, in the present invention, the ultrasonic pulse is transmitted a plurality of times in the first direction along the section to be imaged in the subject, and the first
A first scan that repeats the scan for obtaining the received signal by moving the first direction, and transmitting the ultrasonic pulse a plurality of times in a second direction along the cross section different from the first direction. The scan for obtaining the second received signal for each transmission is performed substantially in parallel with the second scan that is moved in the second direction and repeated from each of the first and second received signals. It is characterized in that two-dimensional distribution image data of the acceleration representing the state of movement of the motion element in the cross section is obtained, and the two-dimensional distribution image data of the acceleration is displayed.

According to the invention described in claim 1, the invention based on the structure of claim 1, and the inventions described in claims 21 and 22, respectively, the moving fluid such as blood flow in the subject can be obtained. The acceleration image of the dimensional distribution is displayed under the CFM mode. The typical operation and effect will be described below.

In the case of the CFM mode, the first
The section to be imaged is scanned (first scan) while transmitting and receiving ultrasonic pulses a plurality of times in the direction of
In parallel with the first scan, a scan (second scan) for tracking the first scan with a certain time difference while transmitting and receiving ultrasonic pulses a plurality of times in a second direction different from the first direction is performed. Will be A tissue signal is removed from the received signals obtained by the first and second scans, and a blood flow signal is obtained. A blood flow velocity is obtained from a blood flow signal based on each of the first and second scans, and blood flow acceleration information is calculated for each pixel from the blood flow velocity and a time difference between the two scans. This acceleration information is displayed as a two-dimensional image.

As described above, since the acceleration of the blood flow can be directly and two-dimensionally displayed in real time, the pulsation can be displayed in a simple and easy-to-understand manner as compared with the conventional blood flow velocity image of the CFM. Therefore, the visibility and discrimination of arteries, portal veins, veins, and the like are significantly improved, which greatly contributes to improvement in diagnostic performance.

Further, the time difference for obtaining the acceleration is constant, and the acceleration in a constant time width can always be obtained irrespective of the setting condition of the apparatus conditions such as the ROI width in the CFM mode. Further, the time difference is one scan line from the time for scanning one scan line (for example, about 4 ms) to the time for subtracting one scan line from the time for scanning one frame (for example, about 200 ms). It can be set at an arbitrary value for each line. As a result, it is possible to reliably detect the rapid rise and fall acceleration of the artery and set the time difference to obtain an accurate value. For this reason, it is possible to accurately and accurately capture even a fast acceleration of the artery under a stable condition of a constant time width, and to obtain a highly accurate acceleration. Therefore, visibility and identification of an artery, a portal vein, a vein, etc. The performance is improved.

In addition, when the acceleration changes rapidly and is displayed in real time as it is, it may be hard to see. In such a case, the change in the acceleration can be reduced and displayed, whereby the visibility can be improved.

Further, transmission and reception based on the first scan and the second scan may be performed simultaneously in parallel, thereby improving the real-time property.

Further, each of the first scan and the second scan may scan a plurality of scanning lines in parallel, thereby improving the acceleration detection ability at a low flow velocity.

Furthermore, if harmonic signals are extracted from the received signals obtained by the first and second scans, a harmonic image of blood flow acceleration can be obtained, an image with less artifacts can be obtained, and diagnostic performance can be obtained. Will be greatly improved.

It is also preferable to obtain a B-mode tomographic image of a scan section and display the B-mode tomographic image superimposed on a two-dimensional acceleration image of blood flow. As a result, the position of the blood vessel can be easily identified, an acceleration image with further improved visibility can be obtained, and diagnostic efficiency is improved.

On the other hand, according to the invention described in claim 2, the invention based on the structure of claim 2, and the invention described in claims 19 and 21, respectively, a moving tissue such as a myocardium in the subject can be obtained. A two-dimensional distribution acceleration image is displayed under the TDI mode. The typical operation and effect will be described below.

In the case of the TDI mode, the first
The section to be imaged is scanned (first scan) while transmitting and receiving ultrasonic pulses a plurality of times in the direction of
In parallel with the first scan, a scan for tracking the first scan with a certain time difference (second scan) is performed while transmitting and receiving the ultrasonic pulse a plurality of times in the second direction different from the first direction. It is. The acceleration is obtained for each pixel from the tissue movement speed obtained from the received signal (tissue signal) of each of the first and second scans and the time difference between the two scans, and is displayed as a two-dimensional distribution acceleration image of the tissue.

Conventionally, the TDI mode is a speed display,
The acceleration display can be newly provided as a real-time two-dimensional image. For this reason, it is thought that it will exert its power in future research on heart disease and the like. The time difference for obtaining the acceleration is constant, and the time difference can be set within a range of about 4 to 20 ms. Therefore, it is possible to accurately capture the motion of the heartbeat under stable conditions that do not depend on the setting state of the device conditions, and to display the acceleration with good visibility and detectability.

If a harmonic signal is extracted from the received signals obtained by the first and second scans, a harmonic image of tissue motion acceleration can be obtained. This harmonic image has fewer artifacts and is superior in depiction ability than an image using a fundamental wave component.

In the present invention, the other functions and effects described in the CFM mode can be similarly enjoyed in the TDI mode.

Further, according to the present invention, since the influence of the speed folding phenomenon obtained when calculating the acceleration is reliably removed, the accuracy of the finally calculated acceleration data is significantly improved. I do. Thereby, stable and reliable acceleration data can be provided.

The present invention may be an ultrasonic diagnostic apparatus and an ultrasonic diagnostic method to be performed on a subject to which an ultrasonic contrast agent has been administered.

[0045]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) Referring to FIGS.
An ultrasonic diagnostic apparatus according to the first embodiment of the present invention will be described.

FIG. 1 shows a schematic configuration of the ultrasonic diagnostic apparatus. This ultrasonic diagnostic apparatus has a CFM function of displaying blood flow information of a subject two-dimensionally.

As shown in FIG. 1, the ultrasonic diagnostic apparatus includes an ultrasonic probe (hereinafter, referred to as an ultrasonic probe) which is brought into contact with the body surface of a subject.
A transmitting unit 2 and a receiving unit 3 electrically connected to the probe 1; a CFM processing unit 4 and a B-mode processing unit 5 electrically connected to the receiving unit 3; A display unit 6 electrically connected to the two processing units 4 and 5, a transmission unit 2, a reception unit 3, and a CFM processing unit 4;
And a scan control unit 7 which is electrically connected to and outputs a control signal.

The probe 1 has a function of bidirectionally converting a signal between an ultrasonic signal and an electric signal. The probe 1 includes, as an example, an array type piezoelectric vibrator linearly arranged at its tip. The array type piezoelectric vibrator has a structure in which a plurality of piezoelectric elements are arranged in parallel, and the arrangement direction is a scanning direction. Each of the plurality of piezoelectric elements forms a transmission / reception channel.

The transmission section 2 includes a transmission pulse generator 2A for generating a transmission pulse, and a transmission beamformer 2B for receiving the transmission pulse. The transmission beamformer 2B
The transmission pulse is subjected to delay control according to the scan method specified by the scan control unit 7 and is converted into a drive pulse signal, which is output to the probe 1. The scanning method is implemented by applying the present invention. In the probe 1, the vibrator is excited for each of a plurality of transmission channels. Thereby, an ultrasonic pulse is transmitted from the probe 1 into the subject according to the scanning method according to the present invention.

The receiving section 3 includes a preamplifier 3A connected to the probe 1 and a receiving beamformer 3B connected to the preamplifier 3A. Although not shown, the preamplifier 3A includes a preamplifier circuit connected to each transducer of the reception channel of the probe 1, and an A / D converter provided for each reception channel on the output side of each of the preamplifier circuits. Thereby, the echo signal of the electric quantity output from the transducer of the receiving channel of the probe 1 is pre-amplified and then converted into a digital quantity.

Although not shown, the reception beam former 3B includes a reception delay circuit provided for each of a plurality of reception channels, and an addition circuit connected to the output side of each of the reception delay circuits. Thus, the echo signal for each reception channel output from the preamplifier 3A is subjected to reception delay and addition processing by the reception beamformer 3B and beamformed. This reception delay processing is performed in response to a control signal sent from the scan control unit 7, and follows the scanning method of the present invention. As a result, a beam-like echo signal that is directed in the same direction as that at the time of transmission is formed by calculation. This echo signal is sent to the CFM mode processing unit 4 and the B mode processing unit.

As shown in FIG. 1, the CFM mode processing section 4 includes, from its input side, a quadrature phase detector 4A, a motion element signal extractor 4B, an electronic switch 4C, and a switch according to the present invention.
First and second speed calculators 4D and 4 provided exclusively for the first and second scans, respectively.
E and an acceleration calculator 4F are provided in this order.

Therefore, in the CFM mode processing section 4, the echo signal is first subjected to quadrature phase detection by the quadrature phase detector 4A. As a result of the quadrature phase detection, an I (In-phase) signal and a Q (Quad)
A Doppler signal is generated, which comprises a signal of a "ratio-phase" signal. By using the I and Q signals, the direction of movement of the moving element (whether the moving element such as a blood flow is approaching or away from the probe) can be separated.

The I and Q signals (hereinafter, generally referred to as “received signals”) are not shown,
It is sent to the motion element signal extractor 4B. The motion element signal extractor 4B has two MTs separately provided for the I and Q signals.
I (Moving Target Indicatio
n) having a filter; These MTI filters remove an echo component (clutter component) generated from almost stationary tissue from each of the I signal and the Q signal using the difference in the Doppler shift amount. As a result, an I signal and a Q signal, each of which consists almost exclusively of the blood flow Doppler signal, are obtained.

On the output side of the motion element signal extractor 4B, a 1-input 2-output electronic changeover switch 4C is provided. The changeover switch 4C switches its output terminal to the first or second output terminal T1 or T2 in response to a control signal sent from a scan control unit 7 described later.
For this reason, the path of the changeover switch 4 </ b> C
Is switched to the first output terminal T1 when the scan: SN1 is indicated, and is switched to the second output terminal T2 when the second scan: SN2 is indicated.

Specifically, the control signal sent from the scan control unit to the changeover switch 4C is, as described later,
4 is a scan sequence for performing a scan based on the present invention. This example is shown in FIGS.

Therefore, when the current scan pointed by the scan sequence is the first scan SN1, the changeover switch 4C switches its output path to the first output terminal T1 as described above. Thereby, the blood flow Doppler signal (digital amount) obtained by the first scan SN1 is sent to the first velocity calculator 4D. On the other hand, when the current scan pointed by the scan sequence is the second scan SN2, the changeover switch 4C switches the output path to the second output terminal T2 as described above. Thereby, the blood flow Doppler signal obtained by the second scan SN2 is sent to the second velocity calculator 4E.
In the case of the scan sequence illustrated in FIGS. 2 to 4, a scan order that is alternately changed for each scan line between the first and second scans: SN1 and SN2 is set. As a result, the first
Scan: SN1 and the second scan: The blood flow Doppler signal obtained in SN2 is supplied to the first and second velocity calculators 4D and 4E alternately for each scanning line according to the instruction of the scan controller 7. Each will be sent.

Each of the first and second speed calculators 4D and 4E includes, for example, an autocorrelator for performing an autocorrelation process on an input Doppler signal, and scans from a calculation result of the autocorrelator. An average speed calculator for calculating an average Doppler frequency (average speed) of each sample point of the cross section, a dispersion calculator for calculating a variance value, and a power calculator for calculating a signal strength (power) are provided. For this reason,
In the first speed calculator 4D, the Doppler frequency f _{d1 at} each sample position of the scan cross section related to the first scan
Is obtained by the autocorrelation method, and this Doppler frequency f _d1
From this, the Doppler velocity V _d1 (blood flow velocity) is obtained based on equation (2) described above. Similarly, the second speed calculator 4E
Also, for the second scan, the Doppler frequency f _d2 is obtained for each sample position on the scan cross section,
The Doppler velocity V _d2 is obtained from the Doppler frequency f _d2 .

The first and second speed calculators 4D and 4D
The Doppler velocities V _d1 and V _d2 calculated in E are sent to the acceleration calculator 4F for each sample point of the scan section. Also, the acceleration calculator 4F receives a time difference T between the first and second scans from a scan control unit 7 described later.
_dif is provided. For this reason,
The acceleration calculator 4F calculates the magnitude of the acceleration of the blood flow at each sample position based on Expression (5) described later.
Distribution data on the size of the scanning section of the thus computed blood flow acceleration A _cc is sent to the display unit 6.

On the other hand, the above-described B-mode processing unit 5 is configured to generate image data of a B-mode tomographic image of a scan section from the echo signal, and send this image data to the display unit 6.

Although not shown, the display unit 6 receives the two-dimensional distribution data and the B-mode tomographic image data of the magnitude of the blood flow acceleration sent from the CFM mode processing unit 4 and the B-mode processing unit 5. A DSC (Digital Scan Converter) is provided, and a color processor, a D / A converter, and a color monitor are provided on the output side. Therefore, DSC
As an example, image data of a standard television scanning method in which two-dimensional distribution data of blood flow acceleration (CFM mode image data) is superimposed on B-mode tomographic image data and an index such as a color bar indicating the magnitude of acceleration is described. Create at a predetermined display rate. Of the image data, pixels exhibiting blood flow acceleration are subjected to color processing of hue and luminance according to the magnitude and direction of the acceleration by the color processor.
The image data processed in this manner is converted into an analog signal and then displayed on a monitor as a blood flow acceleration image in the CFM mode.

On the other hand, as shown in FIG. 1, the scan control unit 7 includes a time difference data setting unit 7A, and first and second scan sequencers 7 provided for the first and second scans.
B and 7C, and an integrated scan sequencer 7D.

In the scan control section 7, the time difference data setting unit 7A uses the time difference T _dif between two scans (first scan and second scan) which is a feature of the present invention.
Is set, and the set value T _dif is sent to the first and second scan sequencers 7B and 7C and the acceleration calculator 4D of the CFM mode processing unit 4. The first and second scan sequencers 7B and 7C respectively generate a scan sequence with a given time difference T _dif and send this to the integrated scan sequencer 7D. The integrated scan sequencer 7D integrates the two received scan sequences to generate a scan sequence arranged in one time series, and converts the scan sequence into a transmission beamformer 2B,
The signal is sent to the receiving beam former 3B and the changeover switch 4C of the CFM processing unit 4.

In the configuration and processing described above, the probe 1, the transmitter 2, the receiver 3, the scan controller 7, and the quadrature detector 4A constitute the scanning means of the present invention, and the motion element signal extractor 4B constitutes the present invention. The first and second velocity calculators 4D and 4E and the acceleration calculator 4F constitute processing means of the present invention, and the display section 6 constitutes display means of the present invention.

Next, a scan sequence for controlling the order of two scans for calculating the acceleration, which is one feature of the present invention, will be specifically described with reference to FIGS. 2 to 4 show the most basic scan sequences according to the present invention.

FIG. 2 is a scan chart showing the scanning order of each of the first and second scanning lines. The horizontal axis shows the arrangement of the scanning lines, and the vertical axis shows time t. In the same figure, a black circle indicates a CFM mode scan in the first scan, a black star indicates a B mode scan in the first scan, a white circle indicates a CFM mode scan in the second scan, and a white star indicates a second scan. 9 shows a B-mode scan in scanning. Also, in FIG.

[Outside 1] Where the first scan, the second scan, the subscripts _i , _k are the scan line numbers, and j, l are the numbers in the data packet in the CFM mode scan. Is shown. Since the CFM transmits an ultrasonic signal a plurality of times in the same scanning line direction, the data for the plurality of times is collectively referred to as a data packet. Also,

[Outside 2] In the symbol, B indicates B-mode scanning.

The transmission cycle (PRT: Pulse R)
epitition Rate) is indicated by Tr. In the following, it is assumed that Tr = 0.25 ms (that is, the pulse transmission frequency PRF = 4 kHz) as an example.

A feature of the acceleration calculation according to the present invention is that two scans (first and second scans) are performed in parallel, and a symbol indicates these two scans in the figure. In addition, the first scan is performed so as to always follow the second scan with a certain time difference. That is, in FIG. 2, the second scan is performed by scanning lines 5, 6, 7,
8, 9, 10,..., Whereas the first scan is performed with scanning lines 1, 2, 3, 4, 5, 6,. Moreover, as can be seen from the timing chart of FIG. 3, both scans are performed alternately for each scanning line.

In the case of the scan sequence shown in FIG. 2, there is always a space of four scanning lines (scanning line interval N _ras ) between the two scanning lines used in the first and second scans.
Is empty. This situation is schematically shown in FIG. 4 (see the first and second scans: SN1 and SN2 in the time period from time t = ta to tb). As an example, CF
The number of data packets of the M mode scan is 16 and 1
The number of transmissions in the scanning line is 17 in total in the CFM mode and the B mode. Therefore, when the scanning line 1 is being scanned by the first scan, the scanning line 5 is being scanned by the second scan. Therefore, the first
Scan reaches scan line 5 because

(Equation 3) After hours. The time difference T _dif can be set in units of one scanning line interval. As an example, it can be set in units of 8.5 ms as in the above-described example.

Next, the overall operation of the ultrasonic diagnostic apparatus according to the present embodiment will be described.

In this ultrasonic diagnostic apparatus, information for instructing a scan sequence is generated by the scan control unit 7 as shown in FIG. That is, when scanning conditions in the CFM mode are input from an operation panel (not shown), the transmission cycle Tr and the number of data packets in the CFM mode are set via the CPU in the console (not shown), whereby the first and second scans are performed. _Are required to scan one scanning line.

In the case of the example given here, the scanning time T
_ras = 8.5 ms. Further, the operator can set a desired time difference by a switch 7SW provided on the time difference setting device 7A. For this reason, the time difference setting device 7A
A value closest to a desired time difference is selected from an integral multiple of the scanning time T _ras , and a scanning line interval N _ras between the two scans (N _ras = 4 in the above example) is determined. Thereby, the time difference setting device 7A obtains the final time difference T _dif from the following equation. That is,

T _dif = T _ras × N _ras (4) The values of the scanning line interval N _ras and the time difference T _dif are obtained from the time difference data setting unit 7A to the first scan sequencer 7.
B, second scan sequencer 7C, acceleration calculator 4D
Sent to Once set, these values N _ras and T _dif are kept constant until they are changed next.

[0074] The first scan sequence 7B and the second scan sequence. _{7C, N ra s} and through the CPU (not shown) from the operation panel (not shown) configured CFM
A first scan sequence and a second scan sequence are generated based on the scan conditions of the mode, and sent to the integrated scan sequencer 7D. In the integrated scan sequencer 7D, the two scan sequences are integrated to generate a series of scan sequences arranged in time series as shown in FIG. A control signal corresponding to the integrated scan sequence is sent to the transmission beamformer 2B, the reception beamformer 3B, and the CFM processing unit 4.

In response to the transmission, the transmission beamformer 2B performs delay control based on the control signal. As a result, the transmission beam direction is determined for each transmission pulse generated by the transmission pulse generator 2A at the transmission interval Tr.
On the other hand, in the receiving beam former 3B, delay control is performed based on the control signal, and for each transmission interval Tr, a receiving beam having directivity in the same direction as the transmitting beam direction is arithmetically formed, and the receiving beam from the subject is calculated. A reflected signal (echo signal) is received. In this way, the first scan and the second scan are executed almost simultaneously (substantially in parallel),
Scans in the M mode and the B mode are performed.

The echo signal collected in this way is CF
It is sent to the M mode processing unit 4 and the B mode processing unit 5. C
The echo signal sent to the FM mode processing unit 4 is subjected to signal processing in the CFM mode and generation of two-dimensional distribution image data of acceleration, while the echo signal sent to the B mode processing unit 5 is a B mode tomographic image. The image data is generated.

Specifically, the CFM mode processing section 4
The echo signal is subjected to quadrature detection to produce I and Q signals capable of separating the direction of blood flow, that is, a received signal. This received signal is sent to the motion element signal extractor 4A. The motion element signal extractor 4B accumulates time-series packet data using the received signal for each sample point on the space forming the scan section. By this series of packet data, a received signal from which a Doppler signal is formed at each sample point includes a reflected wave from a moving object such as a blood cell,
Reflected waves from a fixed object that hardly moves, such as a blood vessel wall or an organ substance, are mixed. In addition, the latter is dominant in terms of the reflection intensity, while the Doppler shift is caused by the Doppler shift, while the Doppler shift is caused by the reflected wave (clutter signal) from the fixed reflector. Almost no occurrence.

Therefore, in the motion element signal extractor 4A, the clutter component is removed from the Doppler signal using the difference in the Doppler shift amount. Thereby, the blood flow Doppler signal is efficiently extracted. This extraction is performed alternately on each of two different scan lines to be scanned in the first and second scans. That is, the blood flow Doppler signals based on the first and second scans are alternately output from the motion element signal extractor 4A in each transmission cycle PRT.

The blood flow Doppler signal is selectively sent to the first or second speed calculator 4D or 4E via the changeover switch 4C which is switched and controlled as described above. That is,
The blood flow Doppler signal in the first direction obtained in the first scan is sent to the first speed calculator 4D, while the blood flow Doppler signal in the second direction obtained in the second scan is obtained in the second direction. 2 is sent to the speed calculator 4E.

In each of the speed calculators 4D and 4E, the Doppler frequency is obtained based on a method such as the autocorrelation method, and then the Doppler speed is obtained based on the aforementioned equation (2). That is, the first speed calculator 4D obtains the Doppler speed V _d1 based on the first scan, and the second speed calculator 4E.
Then, the Doppler velocity V _d2 based on the second scan is obtained. Among them, the Doppler velocity V collected in the second scan
_{Since d2} precedes the first scan with respect to the scanning line number, it is temporarily stored in a memory built in the second speed calculator 4E.

The temporarily stored data of the Doppler velocity V _d2 based on the second scan is synchronized with the output at the time when the data of the Doppler velocity V _{d1 at} the same sample position in the scan section is output. From the speed calculator 4E. As a result, the Doppler velocity data at the same depth on the same scanning line, that is, the Doppler velocity data at the same sample point, is sent from both velocity calculators 4D and 4E to acceleration calculator 4F in synchronization.

On the other hand, the constant time difference data T _dif is sent from the time difference data setting unit 7A to the acceleration calculator 4F. Therefore, the acceleration calculator 4F determines the magnitude of the acceleration Acc for each sample point of the scan cross section.

(Equation 5) Is calculated. This acceleration calculation is sequentially performed on all the sample points forming the scan section, and the calculation result is temporarily stored in the built-in memory.

The data representing the magnitude of the blood flow motion acceleration Acc obtained in this way is sent to the display unit 6. On the other hand, the data of the B-mode tomographic image of the B-mode processing unit 5 is also sent to the display unit 6. Therefore, the display unit 6 performs predetermined image processing, scan conversion processing to standard television scanning, and display processing on the two-dimensional distribution data and tomographic image data of the acceleration Acc in an appropriate order. As a result, for example, as shown in FIG.
The two-dimensional distribution data of the blood flow acceleration is superimposed and displayed on the mode tomographic image.

The display example of FIG. 5 will be described. The monitor image in FIG. 5 shows an image of the magnitude of the two-dimensional acceleration of the artery AR and the vein VE displayed superimposed on the B-mode tomographic image. On the monitor image, a color bar CB indicating the magnitude of the acceleration is simultaneously displayed on the left side of the tomographic image. Color bar C
B is, for example, red when the absolute value of the acceleration is small, and yellow when the absolute value of the acceleration is large. As will be described later, when performing display in consideration of the direction of acceleration, the color bar CB is represented by different hues (for example, red system and blue system) according to the direction.

The graphs of FIGS. 6A and 6B show the time change of the velocity and the time change of the acceleration at a certain sampling point of each of the vein VE and the artery AR. FIG. 7A shows those changes with respect to the vein VE, and FIG. 7B shows those changes with respect to the artery AR.

The artery AR usually has a large pulsatility that spends about one second per heartbeat. For this reason, the magnitude of the acceleration greatly changes as shown in FIG. Therefore, in the image of the artery AR portion in the acceleration images in FIG. 5, the hue greatly changes from red to yellow every cardiac cycle.

On the other hand, since the vein VE shows almost no pulsatility, the absolute value of the acceleration at each sample point is shown in FIG.
Small as shown. Therefore, the image of the vein VE portion in the acceleration image in FIG. 5 is displayed in almost red hue over the entire cardiac cycle.

As described above, the pulsatile state of the blood flow can be reliably drawn by capturing the acceleration of the blood flow and displaying it as a two-dimensional image. For this reason, the characteristic of whether the pulsatility is large or not depending on the type of blood vessel can be presented much more remarkably than the conventionally used image of blood flow velocity display. Thus, the operator can determine the degree of pulsatility of the blood vessel only by visually observing the screen. Therefore,
Whether the blood vessel to be observed is an artery, a vein, or a portal vein can be easily and quickly identified. By improving the visibility at the time of identification, dynamic information of blood flow useful for diagnosis can be provided, which can contribute to improvement of diagnostic performance.

Further, according to the ultrasonic diagnostic apparatus, in addition to the easy identification of the blood vessel type described above, it is possible to detect the blood flow motion information with high accuracy, and to obtain the feature that the information is hardly missed. This is a feature far exceeding the method described in Japanese Patent No. 2768959 for calculating acceleration between frames.

This will be described in detail. As mentioned above, typical beats of the arteries are observed during systole of the heart, and are
During 0 ms, the speed rises sharply and falls, and then falls slowly (see the upper part of FIG. 6B). Therefore, it is necessary to catch the steep rise and fall without fail. In the present embodiment, the first and second two scans are performed substantially in parallel, and the time difference T _dif between the two scans is set to 1
It is a time N _ras corresponding to a positive integer multiple of the time T _ras required to scan a scanning line, and can be set to a time required for scanning less than one frame (the number of scanning lines of one frame minus one scanning line). is there. That is, this time difference T _dif is
From the time T _ras required to scan one scan line,
Within the time required to scan a plurality of scanning lines that is one scanning line less than the number of scanning lines in one frame,
It can be set selectively at any time.

In the above-described example, the time required to scan one scanning line is T _ras = 8.5 ms, and the time required to scan one frame is usually about 200 ms. For this reason, the time difference T _dif is set from 8.5 ms to “20”.
It can be adjusted up to 0-8.5 "ms. For this reason, by setting the time difference T _dif to an appropriate value, information on the rise and fall of the blood flow motion in the systole can be reliably captured with almost no missing.

On the other hand, the acceleration calculation time by the method described in Japanese Patent No. 2768959 is 200 ms in the above example. For this reason, as described above, the number of calculation frames of the acceleration image in the systole is reduced, and the missing motion is conspicuous.

Further, the ultrasonic diagnostic apparatus has a feature that noise resistance can be improved.
As can be seen from equation (5), the greater the time difference _Tdif , the less likely the value of the acceleration is to be affected by noise, and the more stable the calculated value. Therefore, by adjusting the value of the scanning line interval N _ras , the time difference T _dif is still kept at a small value, and a steep pulsation of the artery is surely captured, and a stable acceleration value with improved noise resistance is obtained. Obtainable. This greatly contributes to improvement of diagnostic performance.

Further, the ultrasonic diagnostic apparatus has a feature that the time difference T _dif for calculating the acceleration can be kept constant even if other conditions change. In particular,
As can be seen from Expression (3), the time difference T _dif changes depending on the transmission cycle PRT and the number of data packets in the CFM mode. That is, it changes depending on the setting conditions of the device,
By adjusting the scanning line interval N _ras , the time difference T
_dif can be kept almost constant. Thus, acceleration, that is, pulsation can be detected under a stable condition without being affected by the setting of the imaging condition of the apparatus.

The ultrasonic diagnostic apparatus according to the first embodiment described above can be implemented with various modified configurations. For example, the scan sequences of FIGS. 2 and 3 described above show the most basic forms, and the scan method of the present invention is not necessarily limited to this.
It can be performed in various scan sequences. The scan sequence may be configured, for example, as shown in the following first and second modifications.

(First Modification) A first modification is shown in FIGS.
It will be described based on. This first modification relates to improvement of the detection ability when the blood flow is slow.

The scan sequences shown in FIGS. 7 and 8 are generated by the scan control unit 7. Specifically, a method of alternately scanning a plurality of (for example, four) scanning lines in each of the first and second directions based on the first and second scannings. 4 scanning lines are alternately scanned.
Focusing on one scanning line, the effective PRT is four times (8Tr) the case (2Tr) in FIGS. For this reason, the low flow velocity detection capability, that is, the low acceleration detection capability is improved four times.
Moreover, the time difference T _dif between the first scan and the second scan is the same as in FIGS. 2 and 3, and is adjusted to, for example, 34 ms.

Even in the case of alternately scanning in this manner, the time difference T _dif can be set in the same manner as in FIGS. 2 and 3, and the value of the scanning line interval N _ras is adjusted so that the steep pulsation of the artery can be reduced. It is possible to reliably capture and obtain a stable acceleration. Therefore, the low flow velocity detection capability, that is, the low acceleration detection capability can be improved by the alternate scanning method for each of the first and second scans, and the various effects described in the first embodiment can be obtained together. Therefore, the diagnosis according to this modified example can be useful for a blood vessel having a relatively slow blood flow velocity and a relatively small acceleration, such as a blood vessel such as an abdomen.

(Second Modification) A second modification is shown in FIGS.
0 will be described. The second modification relates to improvement of real-time property (that is, the number of frames).

According to the second modification, in addition to the transmission / reception of a plurality of scanning lines for each scan described in the first modification, the scan control section 7 performs so-called parallel simultaneous transmission shown in FIGS. The first and second scans are respectively performed based on the reception method to improve real-time properties.

That is, as shown in FIG. 9, the first and second directions related to the first scan and the second scan are transmitted and received simultaneously in parallel. Now, the first direction in which ultrasonic transmission / reception is performed as the first scan includes the directions of the scanning lines 1 to 8, and the second direction in which ultrasonic transmission / reception is performed as the second scan is from the direction of the scanning lines 9 to 16. It is assumed to be. In this case, the parallel simultaneous reception is performed by scanning line 1 (first scan) and scanning line 9 (second scan).
Scan), scan line 2 (first scan) and scan line 1
0 (second scan), scan line 3 (first scan), scan line 11 (second scan), and so on. This is performed by the transmission beamformer 2B and the reception beamformer 3B having received the scan sequence (FIG. 10) of the parallel simultaneous reception system transmitted from the scan control unit 7 controlling the amount of delay in transmission and reception.

Each of the first and second scans has eight alternate scans, and the effective PRT is 8Tr, which is the same as in FIG. However, since parallel simultaneous reception is performed,
In both the first and second scans, twice as many scan lines as the scan lines shown in FIG. 7 can be scanned at the same time, and the real-time property, that is, the number of frames can be doubled. Thereby, the diagnostic ability can be further improved. Further, the time difference T _dif between the first and second scans is 34 ms, which is exactly the same as FIG. This time difference T
As described above, _dif can be adjusted by changing the value of the scanning line interval _Nras .

(Third Modification) On the other hand, the scan controller 7
As a configuration example for flexibly setting the condition in, a third modified example can be given.

FIG. 11 shows a configuration example of a scan control unit and an interface to this control unit according to the third modification. As shown in FIG.
A, an alternate scanning line number setting switch 8B, and a parallel simultaneous reception number setting switch 8C are provided on the operation panel, for example, at a position where the operator can operate, as means for setting these parameters.

In response to this, the scan control unit 7 'includes the time difference data setting unit 7A, the first scan sequencer 7B, the second scan sequencer 7C, the integrated scan sequencer 7D, and the number of alternate scanning lines. Setting device 7
E and a parallel simultaneous receiving direction number setting device 7F are provided. The switch output signals of the above-described scan time difference setting switch 8A, alternate scanning line number setting switch 8B, and parallel simultaneous reception direction number setting switch 8C are output from the time difference data setting unit 7A, the alternate scanning line number setting unit 7E, and the parallel simultaneous reception direction. Each is sent to the number setting device 7F.

As a result, the operator can operate these switches 8
By operating A, 8B, and 8C, the time difference between the first and second scans, the number of alternate scanning lines in each scan, and / or the number of parallel simultaneous receptions in each scan can be appropriately selected and set. The setting devices 7A, 7E, and 7F receive the switch signals and set values of the scan time difference, the number of alternate scanning lines, and the number of parallel simultaneous receptions, and set these values to the first scan sequencer 7B and the second scan sequencer 7B. Send to scan sequencer 7C. In this case, as for the scan time difference, as described above, the value closest to the set value of the setting switch 8A is selected by the setting unit 7A.

The first scan sequencer 7B and the second scan sequencer 7C respectively perform the first scan and the second scan based on the set values such as the transmission cycle Tr and the number of data packets in the CFM mode (not shown). A scan sequence of the second scan is generated. The output of the parallel simultaneous reception direction number setting unit 7F is transmitted to the transmission unit 2
, And also output to the receiving unit 3, and the transmission delay and the reception delay are controlled as described above.

Accordingly, the main parameters of the first and second scans can be manually set from outside the apparatus, so that the optimum scan conditions for detecting pulsatility can be set easily and simply.

(Fourth Modification) Further, according to the above-described first embodiment, the following fourth modification can be presented in order to cope with the angle dependency due to the Doppler angle.

The fourth modification will be described with reference to FIGS.

According to the first embodiment, the acceleration of the blood flow is calculated from the blood flow velocity as shown in equation (5). The blood flow velocity is converted from the Dobra frequency, but the Doppler angle θ
Is not obtained without manual intervention, and it is difficult to obtain the Doppler angle θ for each pixel through manual intervention. Therefore, equation (2) is used instead of equation (1). For this reason, the Dobler angle is not corrected, and there is a problem of angle dependence.

Therefore, as shown in FIG. 13 (a), even when the artery AR is the same, when the angle formed with the ultrasonic beam is nearly parallel, such as at the sample point α, the blood flow velocity is almost the original. However, if the angle between the ultrasonic beam and the ultrasonic beam approaches a right angle like another sample point β, it is detected as a velocity lower than the original blood flow velocity. Accordingly, the acceleration is also affected by the angle dependence. When the angle formed by the ultrasonic beam is almost parallel to the acceleration beam, almost the original acceleration can be obtained (see FIG. 13C). When the angle between the ultrasonic beam and the ultrasonic beam is close to a right angle, it is detected as an acceleration smaller than the original acceleration (see FIG. 13D).

To solve this problem, there is a method of normalizing the speed. That is, the velocities shown in FIGS. 13C and 13D are normalized based on the following formula with the average velocities of one heartbeat < _{Vd, α} >, < _{Vd, β} >. Although the average speed of one heartbeat has been described as an example here, the present invention is not limited to this. For example, the maximum speed of the absolute value of one heartbeat, or a value obtained by multiplying the average speed or the maximum speed by a constant value It may be. First, the speed described in FIGS. 13C and 13D is calculated based on the equation (2).
It is necessary to perform division by osθ (θ: Dobra angle).

Therefore, the first and second positions at the sample point α are
Original speed V for 2 scans _{d1, α}', V
_{d2, α}'(The speed to be used in equation (5)) and one core
Average speed of beat <V_{d, α}> '

(Equation 6) Becomes Therefore,

(Equation 7) If the speed of equation (5) is normalized by the average speed of one heartbeat,

(Equation 8) Thus, the problem of angle dependence is solved.

Similarly, also at the sample point β,

(Equation 9) Becomes As shown in FIG. 13B, when the speeds of the sample points α and β are the same in the same blood vessel AR,

(Equation 10) Because

[Equation 11] And the same acceleration is indicated by the same value without depending on the Dobler angle (FIGS. 13B and 13E).

FIG. 13 shows the configuration of the CFM mode processing section for correcting the Doppler angle.

The CFM mode processing unit 14 shown in FIG. 14 includes an average heart rate detector (or a maximum heart rate detector) 1 in addition to the configuration of the CFM mode processing unit 4 shown in FIG.
4A, coefficient multiplier 14B, and Doppler angle corrector 14C
It has.

The outputs of the first scan speed calculator 4D and the second scan speed calculator 4E are input to a heart rate average speed detector (or a heart rate maximum speed detector) 14A and a detection time length setting device (not shown). Is input to the detector 14A. The detection time length is best obtained by obtaining one heartbeat length based on the electrocardiographic synchronization method. However, considering that one heartbeat is about one second, a set value of about one to two seconds may be set for simplicity.

The average heart rate detector 14A calculates, for example, one heart rate average velocity <V _{d, α} > having angle dependency. The calculated value is input to the coefficient multiplier 14B, and the calculated value is multiplied by a constant value. In the example of FIG. 13, the coefficient is 1. While the output of the coefficient multiplier 14B is input to the Doppler angle corrector 14C, the acceleration calculator 4C
The acceleration value that has not been angle corrected, which is the output of F, is input to the Dobler angle corrector 14C.

For this reason, the Doppler angle corrector 14C performs angle correction based on the equation (8) using both input values, and outputs a normalized acceleration value.

Therefore, since the dependence of the acceleration on the Dobra angle can be eliminated, the same pulsating state in the same blood vessel is drawn with the same hue. Thus, it is possible to prevent a situation where the hue changes from a state to be originally displayed due to the Doppler angle, and the visibility of the acceleration image is also improved.

(Fifth Modification) Further, from the viewpoint of improving the visibility of the acceleration image, a fifth modification is configured.

Generally, the change in the acceleration of the artery is 200 to 3
If it occurs within 00 ms, it may be too fast and difficult to see. With respect to this phenomenon, by performing image processing, the speed of change of the acceleration display can be suppressed, and the image can be easily viewed (observed easily).

FIG. 14 shows a display unit 16 for performing this suppression processing.
Is shown. The display unit 16 is an image processor 17 that performs image processing and scan line conversion (scan conversion).
And a monitor 18 for displaying an image. The image processor 17 includes acceleration change alleviators 17A, C
An FM image processor 17B, a B-mode image processor 17C, and a DSC (digital scan converter) are provided.

The acceleration data sent from the CFM mode processing unit 4 to the image processor 17 is input to the acceleration change alleviator 17A. In the acceleration change alleviator 17A,
As shown in FIG. 15, an acceleration relaxation process is performed.

FIGS. 15A to 15C show changes in the acceleration of the artery at one sample point on the scan section.
FIG. 3A shows the acceleration detected by the CFM mode processing unit 4. A curve obtained by calculating the absolute value of the acceleration is shown in FIG. Further, FIG. 3C shows a curve obtained by performing a process of alleviating a change in acceleration.

The specific relaxation process is performed so that the rising of the acceleration is followed, and the falling is gradually reduced by a certain time constant. According to this method, a large acceleration value can be reliably captured, pulsation can be emphasized, and a change in acceleration can be reduced, and visibility can be improved. By adjusting the time constant, a desired image can be obtained. In particular, with a time constant of about one heartbeat, there is almost no display that dynamically beats in time, blood vessels with a strong pulse like an artery are always displayed in yellow, and a pulse with a weak pulse like a vein. The blood vessels are always displayed in red, and a display indicating the intensity of the beat can be statically displayed in time.

Note that the method of the relaxation processing is not limited to the above-described method. For example, a correlation processing (LPF processing) may be performed on values of the same sample point on the scan cross section that are temporally changed.

In the image processor 17, the acceleration data whose change has been suppressed is sent to the CFM image processor 17B and subjected to various image processing. On the other hand, the tomographic image data output from the B-mode processing unit 5 is sent to a B-mode image processor 17C and subjected to various image processing. These C
The outputs of the FM image processor 17B and the B-mode image processor 17C are sent to the DSC 17D, where they are converted into television scan lines, and an image in which acceleration data is superimposed on tomographic image data is generated. This superimposed image is sent to the monitor 18 and displayed.

By performing acceleration data relaxation processing in this manner, an easy-to-see acceleration distribution image can be provided, and functions useful for diagnosis can be enhanced.

(Sixth Modification) The received blood flow echo contains not only the fundamental signal of the transmitted ultrasonic wave but also its harmonic signal. Since the blood flow echo generally has a low intensity, the harmonic signal is not so strong. However, the harmonic signal can be detected with the improvement of the basic performance and the sensitivity of the ultrasonic diagnostic apparatus. Further, in recent years, the development of ultrasonic contrast agents has been activated, and some of them have been commercialized. If this contrast agent is used, the blood flow echo intensity will be about the same as that of the tissue echo, and the microbubbles that are the main component of the contrast agent will generate strong harmonics. Contains harmonic components. Under such circumstances, it is possible to obtain an acceleration image of a two-dimensional distribution of blood flow using harmonic components. This example will be described as a sixth modification with reference to FIG.

FIG. 16A shows the spectrum of a received echo signal before quadrature phase detection. That is, the echo signal, in addition to the fundamental wave component having a frequency _{f 0,} 2f ₀
Mainly has a harmonic component of Although FIG. 2 shows the second harmonic having the strongest signal strength, there are other harmonics having various frequency components.

[0133] To detect the harmonics, performs orthogonal phase detection to the center of 2f _0. That is, as shown in FIG.
After shifting the harmonic to the baseband, only the harmonic is extracted by a low-pass filter (LPF). This process
This is performed by the reception beam former 3B. The acceleration is calculated by the CFM mode processing unit 4 using the harmonic signal in the same manner as in the first embodiment.

[0134] Note that this acceleration operation, the operation speed is performed as described above, used the f _{M =} 2f ₀ in the reference signal frequency of the mixer of the formula (2) for the speed calculation. On the other hand, the speed calculation processing in the embodiment and the modified example described above uses the fundamental wave.
F _M = f ₀ is used as the reference signal frequency of the mixer, and this value f _M = f ₀ is also used in the calculation of Expression (2). Therefore, when an image is generated using the second harmonic as in this modification, the Dobra frequency is doubled for the same blood flow velocity (ie, for the same Dobra frequency,
The blood flow velocity is 1/2).

On the other hand, as for the B-mode tomographic image to be superimposed and displayed, either a fundamental wave or a harmonic wave may be used, and there is no particular limitation. That is, when generating a CFM image using the fundamental wave component, either the fundamental wave or the harmonic can be selected for the generation of the B-mode tomographic image, and also when generating the CFM image using the harmonic component. , Or a B-mode tomographic image can be selected from either a fundamental wave or a harmonic.

As described above, when the harmonic component is used, the artifact is generally reduced and the image quality is improved as compared with the case where the fundamental component is used. Accordingly, it is possible to provide a two-dimensional distribution acceleration image of the blood flow with improved visibility.

(Seventh Modification) This modification relates to another example in which the two-dimensional distribution data of the acceleration calculated as described above is displayed.

More specifically, the CFM mode processing section 4 is provided with a power calculator for calculating the power of the acceleration data.
The display unit 6 displays a two-dimensional acceleration image based on the power value and the acceleration data calculated by the power calculator.

That is, the DSC of the display unit 6 processes the color data of yellow or red (the higher the acceleration, the more the color changes from red to yellow) according to the magnitude of the acceleration. Accordingly, image data is generated in which the brightness of the hue is made brighter or darker (the greater the power, the greater (brighter) the brightness). DCS
Then, data of a color bar CB to be displayed together with the image data is generated. As shown in FIG. 25, the color bar CB changes from a red color to a yellow color along the vertical direction (acceleration increases as the color becomes yellower), and the luminance changes from dark to bright along the horizontal direction. (The brighter, the greater the power).

As a result, the two-dimensional distribution acceleration image displayed together with the color bar CB on the display unit 6 is represented by a difference in hue according to a change in acceleration and a brightness difference according to the power of the acceleration. As a result, the two-dimensional distribution acceleration image is displayed with a three-dimensional effect, so that the image can be more easily viewed and the blood flow information given to the reader becomes richer.

(Second Embodiment) An ultrasonic diagnostic apparatus according to a second embodiment of the present invention will be described with reference to FIGS.

This embodiment relates to an ultrasonic diagnostic apparatus having a TDI function for two-dimensionally displaying information on the movement of a tissue in a subject.

FIG. 17 is a functional block diagram of the ultrasonic diagnostic apparatus. As shown in the figure, a TDI mode processing unit 19 is provided in place of the CFM mode processing unit 4 of FIG. The difference is that the TDI mode processing unit 19 does not use the motion element signal extractor 4A used in the CFM mode processing unit 4, but the rest of the configuration is the same as that of the CFM mode processing unit 4. That is, the TDI mode processing unit 19 includes a quadrature phase detector 19A, a changeover switch 19C, first and second speed calculators 19D and 19E, and an acceleration calculator 19F.

As a result, in the TDI mode processing unit 19, the movement of the tissue can be targeted, and the speed of the movement is the Dobra signal of the echo signal from the tissue, that is, the tissue Dobra, as in the first embodiment. Signal (Tissue Do
(ppler Signal) by the first and second speed calculators 19D and 19E, respectively. Next, using the calculation results of the two calculators 19D and 19E, two-dimensional distribution data of the magnitude of the acceleration of the tissue motion on the scan section is obtained by the acceleration calculator 19F. This acceleration data is superimposed on the B-mode tomographic image on the display unit 6 and displayed as a two-dimensional distribution acceleration image of the movement of the tissue.

In this embodiment, an acceleration image of the heart wall is displayed as an index indicating cardiac function, superimposed on a tomographic image. This display example is shown in FIG. This figure shows a short-axis image of the heart, in which the heart wall WL periodically repeats contraction / expansion with a heartbeat. A color bar CB indicating the magnitude of the acceleration is also displayed on the display screen.

According to this embodiment, the acceleration, which is one of the indices indicating the motor function of the tissue, including the heart, is 2
The image is displayed with good visibility in a state where the position is identified three-dimensionally. Therefore, contribution to clinical and medical research in the future is expected to be great.

The configurations and processes described in the first to sixth modifications are similarly applied to the display of the two-dimensional distribution acceleration image of the tissue motion described in the second embodiment. .

Therefore, when implementing the second embodiment, any of the scanning methods shown in FIGS. 2, 7, and 9 is used, as in the first embodiment. This makes it possible to reliably capture a steep pulsation of the heart and obtain information on the acceleration in a stable manner, thereby greatly contributing to an improvement in diagnostic performance.

Further, the acceleration, that is, the movement of the tissue can be detected under a stable condition without being affected by the setting of the apparatus, and a great power can be exhibited for diagnosis.

Further, as shown in FIG.
And main imaging parameters of the second scan can be easily set from the outside. Therefore, the pulsatility of the tissue can be detected under optimal conditions.

Further, the motion velocity of the tissue is normalized by using the equations (8), (9), etc., so that the Dobra angle dependence of the acceleration can be eliminated. Thereby, the same movement of the tissue can be indicated by the same color, and the visibility is improved.

Further, as shown in FIG. 14, an easy-to-view image can be obtained by relaxing the acceleration data of the tissue motion.

Further, since the signal intensity of the echo from the tissue is stronger than that of the blood flow, a practical intensity of the harmonic signal can be obtained. Therefore, an acceleration image of the tissue can be obtained using the harmonic signal of the tissue echo, and a clear image with less artifact can be obtained.

It should be noted that the present invention is not limited to the configurations described in the above-described embodiments and modifications thereof, and can be implemented in various modifications or combinations without departing from the scope of the claims. It is.

For example, motion (flow or motion)
An example in which only the magnitude of the acceleration is displayed two-dimensionally has been shown, but a code indicating the direction of the acceleration (a code of direction separation)
May be displayed in combination with different hues, for example. Accordingly, the color bar displayed on the display screen is also provided with, for example, hue information indicating the direction.

Further, according to the present invention, a two-dimensional distribution image of acceleration obtained by injecting an ultrasonic contrast agent into a subject and processing an echo signal having an increased intensity may be displayed.

Further, an electrocardiographic gating method may be used in combination with the present invention. As an example, a region of interest (in this case, an area where an acceleration image is to be displayed) on a scan section is scanned for a certain period of time from the R wave of the ECG (electrocardiogram) signal so that the region is scanned in the systole by the above-described scanning method. The scan start may be commanded with only a delay.

Further, in the second embodiment, the power value calculation of the acceleration data according to the seventh modification of the first embodiment may be used together.

(Third Embodiment) Next, a third embodiment according to the present invention will be described. This embodiment relates to a countermeasure against a turning phenomenon when calculating the speed, and the data of the acceleration image may be calculated between the rasters described above, or may be calculated between frames as in the related art.

The CFM mode processing unit 2 according to this embodiment
1 is shown in FIG. 19, and the configuration of the speed difference corrector 21A mounted on the processing unit 21 is shown in FIG. The speed difference corrector 21A includes a speed difference determiner 21Aa and a turn corrector 21A.
b. In addition, the folding-back removing means according to the present invention,
The speed difference corrector 21A (or the speed difference corrector 21A and the time difference data setting device 7A) is configured.

The speed calculation is performed using data packets, and the data packets are discretely sampled data. Therefore, a folding phenomenon occurs in principle based on the sampling theorem. That is,

(Equation 12) Aliasing occurs at a speed V _N corresponding to Ori return frequency f _N given by, - a "V _N". Therefore, the detectable speed range is usually “−V _{N to} V _N ” (FIG. 21,
22).

For example, assuming that the turning speed is 10 cm / s, the identifiable speed is -10 cm / s to 10 c.
m / s. That is, speed = 11 cm / s and speed =-
The difference between 9 cm / s is indistinguishable and usually speed =-
It is erroneously recognized as 9 cm / s (see FIG. 23A).

Accordingly, when a speed turning phenomenon occurs,
The calculation of the acceleration will also be erroneous. For example, the first
Output _V d1 = 11cm / s of speed calculator 4D, the output _V d2 = 8cm / s of the second speed calculator 4E, assuming that a time difference _{T di} f = 100 ms of the first and second scan, the acceleration _Acc = (11-8) / 100 = 30c
m / s ² . However, due to the fact that the speed is mistaken, the acceleration _{A cc = (- 9-8) /} 100 = -170c
m / ^{s 2} and would by mistake.

[0164] In order to improve such an inconvenience, in response to the speed aliasing limit, the speed difference _{V di f "-V} N ~
V _N ”. That is, the speed difference corrector 21A
, The speed difference determiner 21Aa outputs the speed difference “V _d1
−V _d2 ”is determined for the range of“ −V _{N to} V _N ”,
The folding corrector 21Ab calculates a new speed difference V _{dif in} which the influence of the folding phenomenon is removed according to the determination result. Specifically, as shown in FIGS. 24 (a) and (b),

(Equation 13) Is calculated.

As a result, for example, in the case of the above-described example,

[Equation 14] Because

V _dif = (− 9 + 2 × 10) −8 = 3 cm / s, and a true value is obtained (see the double circled equation in FIG. 23A). As a result, the acceleration calculator 4F

(Equation 16) Acceleration _Acc is calculated, and a true value is obtained. Therefore, the influence of the speed turning on the calculation of the acceleration is greatly improved.

However, when the speed difference is significantly different, that is, when the speed difference V _dif exceeds the range of “−V _{N to} V _N ”, it cannot be dealt with only by the above method. As an example, as described above, the speed difference V _dif is −10c.
V _d1 exceeding the range of m / s to 10 cm / s = 31 cm
/ S, V _d2 = 8 cm / s,

[Number 17] Acc = (31-8) / 100 = spite of a 230cm / ^{s 2,}

(Equation 18) Is incorrectly calculated. Under these conditions, even if the above-mentioned countermeasures against speed turning are taken,

V _dif = (− 9 + 2 × 10) −8 = 3 cm / s, and only an incorrect result is obtained (see FIG. 23B).

In the present invention, however, as shown in the above-described embodiment, by operating the switch 7SW (see the time difference setting device 7A), the operator can adjust the time difference T _dif so as to reduce the time difference T _dif , for example, while viewing the image. Can manually change the scanning operation. As a result, when the rise and fall of the speed are fast, the time T _dif for observing the difference between the two speeds can be reduced. Thus, to reduce the speed difference _{V d an if,} the speed difference V
_dif can be within a specified range “−V _{N to} V _N ”.

For example, in the case of the above example, the time difference T _dif
Is reduced to 100/3 = 33 ms, V _d1 = 1
5.7 cm / s, V _d2 = 8 cm / s,

(Equation 20) Then, a true value is obtained (see FIG. 23C).

That is, the speed difference corrector 21A of the present embodiment can sufficiently remove the influence of the speed turning on the acceleration to the extent that there is no practical problem. Therefore, the accuracy of detecting the acceleration can be greatly improved, and the diagnostic performance can be improved.

It should be noted that the configurations described in the above-described embodiments and modifications thereof are merely examples, and the present invention is not necessarily limited to the illustrated configurations, and does not depart from the gist of the claims. Thus, the configuration of the above-described embodiment can be further modified and changed into various modes and implemented.

[0171]

As described above, according to the first aspect, the invention based on the first aspect, and the invention according to the twenty-second aspect, the blood flow is obtained by capturing the acceleration of the blood flow and displaying it two-dimensionally. Pulsatility can be displayed. In other words, the artery, vein, and portal vein can be captured in a state in which the difference in pulsatility is reflected, so that the type of blood vessel can be easily identified at a glance, and visibility is improved. Therefore, useful information for diagnosis is provided, which contributes to improvement of diagnostic performance.

In particular, a steep pulsation can be reliably detected and a stable acceleration can be obtained, which can greatly contribute to improvement in diagnostic performance. Also, without being affected by the device settings,
Acceleration, that is, pulsatility can be detected under stable conditions, and useful information for diagnosis can be provided.

On the other hand, according to the second aspect, the invention based thereon, and the twenty-third aspect, the motion function of the tissue is indicated by capturing the acceleration of the motion of the tissue and displaying it two-dimensionally. One of the indices can be displayed with good visibility. In particular, an acceleration image of the tissue can be obtained by using a harmonic signal of an echo from the tissue, thereby providing a clear image with few artifacts and greatly contributing to improvement of diagnostic performance.

Further, according to the twentieth aspect of the present invention, the influence of the speed folding phenomenon when obtaining the acceleration can be reliably removed, so that the accuracy of the acceleration calculation is remarkably improved, and the stability and reliability are improved. In addition, acceleration data or an acceleration image of a motion element can be provided.

[Brief description of the drawings]

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

FIG. 2 is a scan chart showing a scan sequence of first and second scans in the first embodiment.

FIG. 3 is a timing chart showing a scan sequence of first and second scans in the first embodiment.

FIG. 4 is an explanatory diagram showing a positional relationship on a scanning cross section of a scanning line by first and second scanning.

FIG. 5 is a schematic diagram showing a two-dimensional blood flow acceleration image according to the first embodiment.

FIG. 6 is a diagram illustrating changes in velocity and acceleration at certain sample points for each vein and artery on a blood flow acceleration image.

FIG. 7 is a scan chart of first and second scans according to a first modification.

FIG. 8 is a timing chart showing a scan sequence of first and second scans according to a first modification.

FIG. 9 is a scan chart of first and second scans according to a second modification.

FIG. 10 is a timing chart showing a scan sequence of first and second scans according to a second modification.

FIG. 11 is a block diagram showing a connection between a scan control unit and switches for externally setting scan conditions according to a third modification;

FIG. 12 is a block diagram of a CFM mode processing unit according to a fourth modification in which a function of correcting an angle dependency due to a Doppler angle is incorporated.

FIG. 13 is a diagram illustrating a relationship among a blood flow acceleration image, speed, and acceleration for explaining correction of angle dependence.

FIG. 14 is a block diagram of a display unit having a function of suppressing a change in acceleration according to a fifth modification.

FIG. 15 is a diagram illustrating suppression of a change in acceleration.

FIG. 16 is a view for explaining a process of extracting a second harmonic component in a sixth modification.

FIG. 17 is a block diagram showing a schematic configuration of an ultrasonic diagnostic apparatus according to a second embodiment of the present invention.

FIG. 18 shows a second example of the myocardium displayed in the second embodiment.
FIG. 4 is a display diagram schematically illustrating a dimensional distribution acceleration image.

FIG. 19 is a functional block diagram of a CFM mode processing unit of the ultrasonic diagnostic apparatus according to the third embodiment of the present invention.

FIG. 20 is a functional block diagram of a speed difference corrector used in the third embodiment.

FIG. 21 is a view for explaining the relationship between the speed color bar and the speed turning phenomenon;

FIG. 22 is a diagram for explaining the relationship between the speed circle and the speed turning phenomenon, in which the speed color bars are connected in a circle.

FIG. 23 is a ring diagram of speed for explaining a correction process for speed turning;

FIG. 24 is a ring diagram of speed for explaining a correction process for speed turning;

FIG. 25 is a view showing another example of a color bar when displaying a two-dimensional acceleration image.

[Explanation of symbols]

 Reference Signs List 1 probe 2 transmission unit 3 reception unit 4 CFM mode processing unit 4A quadrature phase detector 4B motion element signal extractor 4C changeover switch 4D, 4E first and second speed calculators 4F acceleration calculator 5 B mode processing unit 6 display Unit 7 Scan control unit 7A Time difference data setting unit 7B, 7C First and second sequencer 7D Integrated sequencer 7E Alternate scanning line number setting unit 7F Parallel simultaneous reception direction number setting unit 8A to 8C Setting switch 14 CFM mode processing unit 14A Heart rate Average speed detector (heart rate maximum speed detector) 14B Coefficient multiplier 14C Doppler angle corrector 17 Image processor 17A Acceleration change alleviator 17B, 17C Image processor 17D DCS 18 Monitor 19 TDI mode processing unit 19F Acceleration calculator 21 CFM mode Processing unit 21A Speed difference corrector 21Aa Speed difference Joki 21Ab aliasing corrector

Claims (23)

[Claims] 1. An ultrasonic diagnostic apparatus for transmitting an ultrasonic pulse to a subject to scan a desired cross section of the subject, wherein the ultrasonic diagnostic apparatus transmits the ultrasonic pulse a plurality of times in a first direction along the cross section. A first scan that repeats a scan for obtaining a first reception signal for each transmission by moving the first direction, and a second scan along the cross section different from the first direction.
A scan in which a scan for obtaining a second reception signal for each transmission while transmitting the ultrasonic pulse a plurality of times in the direction of is repeated substantially in parallel with moving the second direction. Means for extracting, from each of the first and second received signals, first and second motion element signals representing the state of motion of the motion element in the cross section for each sample point of the cross section; Processing means for obtaining two-dimensional distribution image data of acceleration representing the state of movement of the motion element based on first and second motion element signals; and display means for displaying the two-dimensional distribution image data of acceleration. An ultrasonic diagnostic apparatus characterized by the above-mentioned. 2. An ultrasonic diagnostic apparatus for transmitting an ultrasonic pulse to a subject and scanning a desired section of the subject, wherein the ultrasonic pulse is transmitted a plurality of times in a first direction along the section. A first scan that repeats a scan for obtaining a first received signal for each transmission by moving the first direction, and a second scan along the cross section different from the first direction.
A scan in which a scan for obtaining a second reception signal for each transmission while transmitting the ultrasonic pulse a plurality of times in the direction of is repeated substantially in parallel with moving the second direction. Means for obtaining, from each of the first and second received signals, two-dimensional distribution image data of acceleration representing the state of movement of the motion element in the cross section; and displaying the two-dimensional distribution image data of acceleration. An ultrasonic diagnostic apparatus comprising: a display unit. 3. The ultrasonic diagnostic apparatus according to claim 1, wherein the scanning unit performs the first and second scans for each scan line on the cross section based on the ultrasonic pulse. An ultrasonic diagnostic apparatus comprising: a scan control unit that causes one of the scans to follow the other scan with a certain time difference. 4. The ultrasonic diagnostic apparatus according to claim 3, wherein each of the first and second directions comprises one direction that is changed every time the transmission and reception of the plurality of times in each direction are completed. An ultrasonic diagnostic apparatus characterized by the above-mentioned. 5. The ultrasonic diagnostic apparatus according to claim 4, wherein the scan control means causes the ultrasonic pulse to be transmitted alternately once in the first and second directions at regular intervals of the predetermined time. An ultrasonic diagnostic apparatus for performing the transmission a plurality of times in each of the first and second directions. 6. The ultrasonic diagnostic apparatus according to claim 3, wherein each of the first and second directions comprises a plurality of directions that are changed each time the plurality of transmissions in each direction are completed, The scan control means causes the ultrasonic pulses to be transmitted in parallel in the plurality of first directions so that the transmission is performed a plurality of times in each direction, and the plurality of transmissions is performed in each direction. An ultrasonic diagnostic apparatus, which is means for transmitting the ultrasonic pulses in the plurality of second directions in parallel. 7. The ultrasonic diagnostic apparatus according to claim 6, wherein the scan control unit transmits the ultrasonic pulse once in each of the plurality of first directions and the second plurality of second ultrasonic pulses. An ultrasonic diagnostic apparatus comprising: means for alternately performing one transmission of the ultrasonic pulse in each direction in the direction at predetermined time intervals. 8. The ultrasonic diagnostic apparatus according to claim 3, wherein the processing unit obtains a speed from each of the first and second motion element signals, and uses the two speeds and the fixed time difference. An ultrasonic diagnostic apparatus comprising an arithmetic unit for calculating the acceleration for each of the sample points. 9. The ultrasonic diagnostic apparatus according to claim 8, wherein the processing unit corrects the acceleration according to an angle between the beam of the ultrasonic pulse and a direction of movement of the motion element. An ultrasonic diagnostic apparatus comprising: 10. The ultrasonic diagnostic apparatus according to claim 9, wherein the correction unit is configured to calculate an average speed or a maximum speed of a predetermined period of the movement of the motion element or a time corresponding to the predetermined period, or an average thereof. An ultrasonic diagnostic apparatus, which is means for normalizing the acceleration using a value obtained by multiplying a speed or a maximum speed by a constant value. 11. The ultrasonic diagnostic apparatus according to claim 3, wherein said processing means includes a relaxation means for mitigating a temporal change of said acceleration. 12. The ultrasonic diagnostic apparatus according to claim 3, further comprising a time difference adjusting unit that can adjust the fixed time difference between the first scan and the second scan. Ultrasound diagnostic device. 13. The ultrasonic diagnostic apparatus according to claim 12, wherein the adjustable constant time difference is determined based on a time required to scan one scan line based on the ultrasonic pulse and a plurality of scans for one frame. An ultrasonic diagnostic apparatus characterized in that the difference is a desired time difference until a time required for scanning a plurality of scanning lines one less than the line. 14. The ultrasonic diagnostic apparatus according to claim 12, wherein said time difference adjusting means is means capable of manually adjusting said predetermined time difference. 15. The ultrasonic diagnostic apparatus according to claim 3, wherein the scanning unit causes the transmission of the first scan and the transmission of the second scan to be performed simultaneously in parallel, so that the first and second reception signals are transmitted. An ultrasonic diagnostic apparatus comprising: a parallel simultaneous reception command means for simultaneously receiving data. 16. The ultrasonic diagnostic apparatus according to claim 3, further comprising a harmonic extraction unit that extracts a harmonic signal from each of the first and second reception signals obtained by the scanning unit. An ultrasonic diagnostic apparatus characterized by the above-mentioned. 17. The ultrasonic diagnostic apparatus according to claim 1, further comprising: a B-mode tomographic image obtaining unit configured to obtain a B-mode tomographic image of the cross section, wherein the display unit includes the B-mode tomographic image and the acceleration. An ultrasonic diagnostic apparatus having means for displaying the two-dimensional distribution image of the above on the same monitor. 18. The ultrasonic diagnostic apparatus according to claim 17, wherein the display means displays the acceleration of the B-mode tomographic image in the B-mode tomographic image.
An ultrasonic diagnostic apparatus comprising means for superimposing and displaying a dimensional distribution image. 19. The ultrasonic diagnostic apparatus according to claim 1, wherein said processing means obtains a speed from each of said first and second motion element signals, and controls an influence of a turning phenomenon of said speed. An ultrasonic diagnostic apparatus comprising a folding-back removing means for removing. 20. A scanning unit for transmitting an ultrasonic pulse to a subject to scan a desired section of the subject and obtaining a reception signal for the transmission, and detecting a movement of a motion element existing in the section from the reception signal. An ultrasonic diagnostic apparatus comprising: a speed calculating unit that calculates a speed; and an acceleration calculating unit that calculates an acceleration of the movement of the motion element using the speed, wherein the speed calculating unit includes a turn of the speed. An ultrasonic diagnostic apparatus, comprising: folding back means for removing the effect of a phenomenon. 21. An ultrasonic diagnostic apparatus for transmitting an ultrasonic pulse to a subject to scan a desired section of the subject, wherein the ultrasonic pulse is transmitted a plurality of times in a first direction along the section. A first scan that repeats a scan for obtaining a first received signal for each transmission by moving the first direction, and the ultrasonic pulse in a second direction along the cross section different from the first direction Scanning means for performing a scan for obtaining a second reception signal for each transmission while transmitting a plurality of times by moving the second direction and repeating the second scan substantially in parallel, The time difference between the transmission of the ultrasonic pulse in the first direction based on the scan and the transmission of the ultrasonic pulse in the second direction based on the second scan is represented by 1 based on the ultrasonic pulse. For scanning scan lines From time to, ultrasonic diagnostic apparatus characterized by being set to a desired time difference between the up time required to one less scan a plurality of scan lines than the plurality of scanning lines for one frame. 22. A scan for obtaining a first reception signal for each transmission while transmitting an ultrasonic pulse in a first direction along a section to be imaged in the subject a plurality of times in the first direction. A first scan to be repeated and a scan to obtain a second reception signal for each transmission while transmitting the ultrasonic pulse a plurality of times in a second direction along the cross section different from the first direction. Performing a second scan that is repeated while moving in the second direction, substantially in parallel with each other, and first and second representing the state of motion of the motion element in the cross section from each of the first and second received signals. A second motion element signal is extracted for each sample point of the cross section, and two-dimensional distribution image data of acceleration representing a motion state of the motion element is obtained based on the first and second motion element signals. Display two-dimensional distribution image data of An ultrasonic diagnostic method, comprising: 23. A scan for obtaining a first reception signal for each transmission while transmitting an ultrasonic pulse a plurality of times in a first direction along a section to be imaged in the subject in the first direction. A first scan to be repeated and a scan to obtain a second reception signal for each transmission while transmitting the ultrasonic pulse a plurality of times in a second direction along the cross section different from the first direction. The second scan that is repeated while moving in the second direction is performed substantially in parallel. From each of the first and second received signals, the acceleration 2 representing the state of motion of the motion element in the cross section is calculated. An ultrasonic diagnostic method comprising: obtaining two-dimensional distribution image data; and displaying the two-dimensional distribution image data of the acceleration.