JPH0479942A - Ultrasonic diagnosing device - Google Patents

Abstract

PURPOSE:To provide color display of the magnitude and direction of blood flow and enable the magnitude and direction of the velocity of blood flow to be easily noticed in real time by converting the amplitude data and angle data of blood flow velocity data into brightness data, hue data and saturation data using a matrix which can be varied with different portions to be observed. CONSTITUTION:In a color synthesis processing circuit 6A, color bar data for the two-dimensional vector data of blood flow velocity data is generated by a color bar generating table 10 and is fed to an MPX 11. The blood flow velocity data is read out from a blood flow image memory 5F and fed to the MPX 11 and is added to the color bar data and the added outputs are fed to an RGB converting table 12. Using a matrix M that corresponds to a select signal ST fed from a controller 7B, the magnitude data and angle data of blood flow velocity data from the blood flow image memory 5F is converted into hue data H, saturation data S and brightness data 1 as three attributes of color by a modulation matrix circuit 12A and are further converted into e.g. R data (red), G data (green) and B data (blue) by an RGB converting circuit 12B using.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention transmits and receives ultrasonic waves to and from a subject, and generates tomographic images and two-dimensional blood flow images based on the signals obtained thereby. The present invention relates to an ultrasonic diagnostic device that displays.

(Prior art) In an ultrasound diagnostic device, ultrasound is transmitted from an ultrasound probe to a living body using the pulse reflection method, and a tomographic image (also known as a B-mode image) is created based on the reflected ultrasound (echo) from the living body. say.)
can be obtained.

In addition, using the ultrasound Doppler method, ultrasound is transmitted to the living body,
By obtaining the frequency shift due to the Doppler effect from the phase change of the reflected wave echo, it is possible to obtain motion information of the moving object at the depth position where the echo was obtained.

According to this ultrasonic Doppler method, it is possible to know the size and direction of blood flow at a position in a living body.

Next, a device to which this ultrasonic Doppler method is applied will be explained. First, in order to obtain blood flow information from ultrasound reception signals,
The ultrasonic probe is driven by a transmitting circuit to repeatedly transmit ultrasonic waves in a certain direction a predetermined number of times, and the received signal is detected by a quadrature phase detection circuit to separate Doppler shift signals caused by blood cells and clutter components. We get a signal consisting of This signal is converted into a digital signal and clutter components are removed by a filter.

Furthermore, to obtain a color Doppler image in real time, the Doppler signal due to blood flow is frequency-analyzed using a high-speed frequency analysis circuit, and the average value of the Doppler shift is calculated.

Obtain the variance value of the Doppler shift, the average intensity of the Doppler shift, etc. In addition, blood velocity color flow mapping data is obtained using an autocorrelator built into the frequency analysis circuit, and this data is color-processed to create a color flow mapping image (CFM image) as two-dimensional blood flow information on a tomographic image. ) are displayed on the TV monitor in an overlapping manner.

In the color processing, blood velocity data in the ultrasound beam direction is one-dimensionally colored according to the direction and size of the blood flow, for example, colored in red or blue.

Also, when blood velocity data or vector data is given as angle data θ and size data r, the blood velocity is
Although it is necessary to display the vector data in a dimensional manner, this vector data has been displayed using arrows, streamlines, etc.

(Problems to be Solved by the Invention) However, displaying blood velocity data using arrows or streamlines is not suitable for real-time display.

In other words, it is difficult to intuitively express the direction and size of blood flow in real time. Furthermore, in the past, there was no way to display vector data of blood flow velocity data in an easy-to-understand manner.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an ultrasonic diagnostic apparatus that displays the direction and magnitude of blood flow as blood velocity in an easy-to-understand manner in real time, thereby reducing the operational burden on the operator.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems and achieve the objects, the present invention takes the following measures. The present invention provides an ultrasonic diagnostic apparatus that obtains blood flow velocity data consisting of tomographic image data, size data, and angle data based on received signals obtained by transmitting and receiving ultrasound waves to and from a subject. The tomographic image data of the point is compared with a first threshold, and the magnitude data of the blood flow velocity data of the observation point is compared with a second threshold, and the data of the observation point is converted into tomographic image data. or includes means for obtaining composite image data by adding tomographic image data or blood flow velocity data of a plurality of observation points determined to be blood velocity data,
It is characterized by displaying a composite image.

Further, in an ultrasonic diagnostic apparatus that obtains blood flow velocity data consisting of tomographic image data, size data, and angle data based on a received signal obtained by transmitting and receiving ultrasound waves to and from a subject, the blood flow velocity data Conversion means for converting size data and angle data into brightness data, hue data, and saturation data using a matrix that varies according to the observation site of the subject is provided, and the size and direction of blood flow are displayed in color. It is characterized by what it did.

The conversion means is characterized in that it converts size data into brightness data and converts angle data into hue data.

The conversion means is characterized in that it converts size data into saturation data and converts angle data into hue data.

The conversion means is characterized in that it converts size data into hue data and converts angle data into brightness data.

(Effects) By taking such measures, the following effects are achieved. Comparison of tomographic image data at any observation point with the first threshold value, comparison of blood flow velocity data with the second threshold value,
The data at the observation point is determined to be tomographic image data or blood flow velocity data by comparison with the threshold value of Because it doesn't use data,
The combined image is free from the influence of angle dependence, and it is possible to improve the blood flow detection ability of a color flow mapping image in which, for example, a monochrome image of the abdomen and blood flow in each direction are mixed.

In addition, the amplitude data and angle data of the blood flow velocity data are converted into brightness data, hue data, and saturation data using a matrix that varies depending on the observation area of the subject, and the size and direction of blood flow can be expressed by color. Since the three attributes are displayed in color, it is easier to understand the magnitude and direction of the blood flow velocity in real time than by displaying arrows or streamlines.

(Example) Hereinafter, specific examples of the present invention will be described.

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

The ultrasonic diagnostic device includes an ultrasonic probe 1. The transmission system 2 includes a pulse generator 2A, a transmission delay circuit 2B, and a balsa 2C. The ultrasonic probe 1 includes a plurality of piezoelectric transducers, and these transducers transmit and receive ultrasonic pulses to and from a subject.

The rate pulse is generated by a pulse generator 2A and supplied to a transmission delay circuit 2B. The rate pulse is given a predetermined delay time for each transducer in order to converge the ultrasound beam in a predetermined direction by the transmission delay circuit 2B,
This delayed rate pulse is supplied to pulser 2C. and the pulser 2 based on the delayed rate pulse.
C, each vibrator of the ultrasonic probe 1 is repeatedly driven a predetermined number of times.

When the ultrasound probe 1 is driven to transmit by the balsa 2C, the ultrasound pulses transmitted from the ultrasound probe 1 to a living body (not shown) are reflected ultrasound waves caused by blood flow flowing in the living body, blood vessels, etc. The received signal is accompanied by reflected ultrasonic waves from walls and the like, and is received by the same transducer of the ultrasonic probe 1.

The receiving system 3 includes a preamplifier 3A, a receiving delay circuit 3. It consists of an adder 3C. The received signal is amplified to a predetermined level by a preamplifier 3A, and a reception delay circuit 3B gives a delay time opposite to the delay time given by the transmission delay circuit 2B to the reception signal from each vibrator. Furthermore, the received signals from each vibrator are added by an adder 3C,
The output of the adder 3C is supplied to the B-mode processing system 4 and the CFM processing system 5.

The B-mode processing system 4 includes a logarithmic amplifier 4A, an envelope detection circuit 4B, an A/D (analog-to-digital conversion) 4C, and a monochrome image memory 4D. The received signal output from the adder 3C is logarithmically amplified by a logarithmic amplifier 4A, and the envelope of the signal from the logarithmic amplifier 4A is detected by an envelope detection circuit 4B. The detection output from the envelope detection circuit 4B is converted into a digital signal by the A/D 4C and written into the monochrome image memory 4D as tomographic image data (B-mode image data). The data read from the black and white image memory 4D is supplied to the composition processing circuit 6A.

The CFM (color flow mapping) processing system 5 includes a phase detection circuit 5A, an A/D 5B, an MTI filter 5C, an autocorrelator 5D, an arithmetic unit 5E, and a blood flow image memory 5F.

The received signal from the adder 3C is taken into a phase detection circuit 5A, and quadrature phase detection is performed by the phase detection circuit 5A,
High frequency components are removed by a low-pass filter (not shown) to obtain a Doppler shift signal, that is, a Doppler detection output for a blood flow image.

This Doppler detection output includes, in addition to blood flow information, unnecessary reflected signals (clutter components) from slow-moving objects such as the wall of the heart. Furthermore, the Doppler detection output is A
/D 5 B converts it into a digital signal and sends it to MT
It is supplied to I filter 5C.

MTI is a technology used in radar.Movin
g Target Indicator is a method of detecting only moving targets using the Doppler effect.

The MTI filter 5C detects the movement of blood flow based on the phase change between the same pixels in the N rate pulses, and removes clutter. The Doppler signal from which clutter has been removed is subjected to frequency analysis by an autocorrelator 5D.

The calculating section 5E has an average speed calculating section 1, a dispersion calculating section, and a power calculating section inside. Based on the frequency-analyzed Doppler signal, the average velocity calculation unit calculates the average Doppler shift frequency f.
d is found, the variance σ2 is found by the variance calculation unit,
The total power TP is determined by the power calculation section.

Furthermore, the blood flow information from the arithmetic unit 5E is written into the blood flow image memory 5F, and the data read from the blood flow image memory 5F is supplied to the synthesis processing circuit 6A.

The display system 6 consists of a composition processing circuit 6A, a D/A 6B, and a color monitor 6C, and the control system 7 consists of an operation console 7A and a controller 7B. The controller 7B controls the transmission system 2. Receiving system 3. B mode processing system 4. It has 5 CFM processing systems.

Next, the features of this embodiment will be explained. Second
The figure shows details of the color synthesis processing circuit 6A and its peripheral circuits, and FIG. 3 shows the RG in the color synthesis processing circuit.
A diagram showing the details of the B conversion table, Figure 4 is a diagram in which line A is set along the ultrasound transmission direction with respect to the blood vessel, and Figure 5 is a diagram showing the tomographic image data and blood flow velocity data on the line A. FIG. 6 is a diagram showing the conditions for obtaining the composite data.

The color composition processing circuit 6A uses the color bar generation table 1
0, multiplexer 11, 15 (hereinafter referred to as MPX)
, RGB conversion table 12, attenuator table 13
1 composite logic circuit 14.

The color bar generation table 10 generates two-dimensional vector data of blood velocity data, that is, blood flow size data (r-direction component), angle data (θ
color bar data for the directional component) is generated and this color bar data is provided to MPXII. Blood flow velocity data (size data, angle data) is read out from the blood flow image memory 5F and supplied to the MPXII.

The color bar data and the blood flow velocity data are added by MPXII, and the added output is converted into RGB conversion table 1.
2.

The RGB conversion table 12 includes a modulation matrix circuit 12A and an RGB conversion circuit 12B, as shown in FIG. Note that a selection signal ST for selecting a display mode according to the observed region of the subject is input from the controller 7B to the modulation matrix circuit 12.

Using the matrix M corresponding to the selection signal ST supplied from the controller 7B, the magnitude data and angle data of the blood flow velocity data from the blood flow image memory 5F are converted into three attributes of color by the modulation matrix circuit 12A. Hue data H1, saturation data S, and brightness data I are converted as follows. That is, the data conversion into hue data H1, saturation data S, and brightness data (2) is expressed by the following equation.

Note that the hue H2, the saturation S, and the brightness I are expressed using Munsell's color solid or the like. Further, the RGB conversion circuit 12B converts the hue data H1 saturation data S and brightness data 1 into R data (red), G data (green), and B data (blue) using, for example, a fern graph. The B-mode image data from the monochrome image memory 4D is attenuated by a predetermined amount by the attenuation setting value ATT from the attenuator table 13, and the attenuator output is M P
15.

Next, the synthesis logic circuit 14 will be explained using FIGS. 4 to 6. As shown in FIG. 4, the synthesis logic circuit 14 compares the tomographic image data E at an arbitrary observation point on the line A with a first threshold value BWth, and compares the magnitude of the blood flow velocity data at the observation point. data v norm
is compared with the second threshold value vth, and the data at the observation point is determined to be tomographic image data (black and white data) or blood flow velocity data (color data), and the determined plurality of observations on the line A are determined. This is to add tomographic image data or blood flow velocity data at a point.

Next, the operation of the synthesis logic circuit 14 will be explained. First, as shown in FIG. 4, the operator sets line A for blood vessels running left and right by operating the console 7A. Then, as shown in FIG. 5(a), an arbitrary observation point on line A, for example, blood vessel wall R,, R2, is detected by the transmission and reception of ultrasonic waves.
The position y on the y-axis corresponding to . , yl are obtained, and this tomographic data is written into the monochrome image memory 4D. Also, as shown in FIG. 5(b), any observation point on line A, for example, the position on the y-axis corresponding to blood flow S)
Blood flow velocity data is obtained at '++Y2, and the blood flow velocity data is written to the blood flow image memory 5F. Then, under the control of the controller 7B, composite image data is obtained by the composition logic circuit 14 according to composition logic as shown in FIG. For example, on line A shown in Fig. 4, at the observation point of blood vessel wall R1, E≧B Wth, V norn+< V th, so it is determined that the tomographic image data is B/W, and at the observation point of blood flow S, E <B Wth, V nori+≧Vth, so it is determined that the blood flow velocity data is C0LOR, and at the observation point of the blood vessel wall R2, E≧B W th, V norm<V th, it is determined that the tomographic image data is B/W.

These tomographic image data or blood flow velocity data on line A are added to obtain composite image data as shown in FIG. 5(C), and the composite image data is supplied to the MPX 15.

Then, in the MPX 15, the blood flow velocity data of the composite image data is expressed in color using the RGB data from the RGB conversion table 12, and the brightness of the tomographic image is adjusted using the attenuator output for black and white from the attenuator table 13. Further, these data are converted into analog by the D/A 6B, and a composite image, that is, blood flow velocity is displayed in color, and tomographic images of blood vessel walls, etc., are displayed in black and white on the color monitor 6C.

In this way, by comparing the tomographic image data at an arbitrary observation point with the first threshold value and comparing the size data of the blood flow velocity data with the second threshold value, the data at the observation point can be converted into tomographic image data or Since the tomographic image data or blood flow velocity data at multiple observation points determined as blood velocity data are only added together, and the angular data of the blood velocity data is not used, the composite image is free from angle-dependent effects. is gone,
For example, it is possible to improve the blood flow detection ability of a color flow mapping image in which a monochrome image of the abdomen and the like and blood flow in various directions are mixed. Moreover, the sense of incongruity with conventional color flow mapping images is reduced.

In addition, the size data and angle data of blood flow velocity data,
a matrix M that varies depending on the observation site of the subject;
By brightness data, hue data.

The size and direction of blood flow are converted to saturation data and displayed in color using three color attributes, making it easier to understand and operate in real time than when the size and direction of blood flow velocity are displayed using arrows or streamlines. This can reduce the burden on people. Furthermore, by changing the matrix M, it is possible to select a coloring method according to the observed part of the subject.

Next, a second embodiment of the present invention will be described.

In the second embodiment, as described above, the coloring method can be selected according to the observed part of the subject, and the coloring method, for example, M, 2, . M3. RGB conversion table 122 and attenuator table 13. which convert angle data of blood flow velocity data into hue data HD and size data into brightness data ID by setting M other than zero to zero. MPX
15 in the synthesis processing circuit 6A-2, and a monochrome image memory 5F-2 for storing blood flow velocity data as X-direction velocity data Vx and y-direction velocity data vy.

FIG. 8 is a diagram showing a method of coloring the vector display of blood flow velocity in the second embodiment. In FIG. 8, the color is black near the origin O, the brightness increases as the distance from the origin O increases, and the hue H is assigned in the angular direction. FIG. 9 is a diagram showing Munsell's H5I color space. The side frame (shaded area) shown in FIG. 9 is made to correspond to the two-dimensional X direction shown in FIG. 8, and the coloring method in the X direction.

In this way, the hue H is made to correspond to the angle, and the brightness I is made to correspond to the radial direction for color display, so for example, as shown in FIG. The blood flow dynamics can be determined in real time by the difference in hue H and the size of the blood flow by the brightness I of the color.

Next, a third embodiment of the present invention will be described.

In the third embodiment, a coloring method can be selected according to the observed part of the subject, and as shown in FIG. 11, the RGB conversion table 12-2 of the second embodiment is replaced with For example, M12 . By setting M other than M21 to zero, the angle data of blood flow velocity data can be changed to hue data H.
The difference is that an RGB conversion table 12-3 is used to convert size data into chroma data SD and size data into chroma data SD.

FIG. 12 is a diagram showing a method of coloring the vector display of blood flow velocity in the third embodiment. In Figure 12,
The color is black near the origin O, and the saturation S decreases as it moves away from the origin O, and the hue H is assigned in the angular direction. FIG. 13 is a diagram showing Munsell's H5I color space.

Locus S of coordinate changes in the HSI color space shown in Fig. 13.
S2. S3 is shown in Figure 12 in two dimensions (X direction, X direction)
Corresponds to the coloring method.

In this way, the hue H corresponds to the angular direction and the saturation S corresponds to the radial direction for color display.For example, as shown in FIG. Due to the difference in the size of the blood flow, the blood flow dynamics can be determined in real time based on the color saturation S.

Next, a fourth embodiment of the present invention will be described.

In the fourth embodiment, it is possible to select a coloring method according to the observed part of the subject, and as shown in FIG. Among the matrices, for example, M1□ is selected by a selection signal from the controller 7B.

RGB conversion table 1 that converts angle data of blood flow velocity data into brightness data I and size data into hue data H by setting M other than M s 2 to zero.
The difference is that 2-4 is used.

FIG. 16 is a diagram showing a method of coloring the vector display of blood flow velocity data in the fourth embodiment.

In Fig. 16, the area near the origin O is black, and the angle θ
In the range of 1≦θ≦62, the hue H is reddish, and in the angle range other than the above angle range, the hue H is that of fruits and vegetables.

FIG. 17 is a diagram showing Munsell's H3I color space.

Changes H, , H2 in the hue H of the outer periphery shown in FIG.
It corresponds to the two-dimensional (X direction, X direction) coloring method shown in the figure.

In this way, the change in hue H2 is set in the range of angle θ1≦θ≦02, and the change in hue H2 is displayed in color in correspondence with the radial direction of the other angle ranges. For example, as shown in FIG. Regardless of the angle of the blood flow, the size of the blood flow is accurately displayed by the hue H.

Note that the present invention is not limited to the embodiments described above. Blood flow size and direction brightness 1 hue.

Conversion to saturation is not limited to the second to fourth embodiments, and may be other conversions. It goes without saying that various other modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the present invention, observation can be performed by comparing tomographic image data at an arbitrary observation point with a first threshold value and by comparing magnitude data of blood velocity data with a second threshold value. The data at a point is determined to be tomographic image data or blood flow velocity data, and the determined tomographic image data or blood flow velocity data at multiple observation points are added together, and the angle data of the blood flow velocity data is not used. The effect of angle dependence is eliminated, and the ability to detect blood flow in a color flow mapping image in which a monochrome image of the abdomen and blood flow in various directions are mixed can be improved.

In addition, the amplitude data and angle data of the blood flow velocity data are converted into brightness data, hue data, and saturation data using a matrix that varies depending on the observation area of the subject, and the size and direction of blood flow are expressed in color. Since the three attributes are displayed in color, it is easier to understand the magnitude and direction of blood flow velocity in real time than by displaying arrows or streamlines, and it is possible to provide an ultrasonic diagnostic apparatus that can reduce the burden on the operator.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram showing an embodiment of the ultrasonic diagnostic apparatus according to the present invention, and FIG. 2 is the color composition processing circuit 6A.
and a diagram showing details of this peripheral circuit; FIG. 3 is a diagram showing details of an RGB conversion table in the color composition processing circuit;
Figure 4 shows line A along the ultrasound transmission direction with respect to the blood vessel.
5 is a diagram showing the composite image data obtained by adding the tomographic image data and blood flow velocity data on the line A, and FIG. 6 is a diagram showing the conditions for obtaining the composite image data. 7 to 10 are diagrams for explaining the second embodiment of the present invention, and FIGS. 11 to 14 are diagrams for explaining the third embodiment of the present invention. Figures 15 to 18
The figure is a diagram for explaining a fourth embodiment of the present invention. 1... Ultrasonic probe, 2A... Pulse generator, 2B
... Transmission delay circuit, 2C ... Balsa, 3A ... Preamplifier, 3B ... Reception delay circuit, 3C ... Adder, 4A ... Logarithmic amplifier, 4B ... Envelope detection circuit,
4C...A/D. 4D...Black and white image memory, 5A...Phase detection circuit, 5B...A/D, 5C...MTI filter, 5D
... Autocorrelator, 5E... Arithmetic unit, 5F... Image memory for blood flow, 6A... Color synthesis processing circuit, 6B.
...D/A, 6C...Color monitor, 12...RG
B conversion table, 12A...modulation matrix, 12
B...RGB conversion circuit, 13...Attenuator table, 4...Synthesis logic circuit, 11°5...MPXo

Claims (5)

[Claims] (1) In an ultrasound diagnostic apparatus that obtains blood flow velocity data consisting of tomographic image data, size data, and angle data based on received signals obtained by transmitting and receiving ultrasound waves to and from a subject,
The tomographic image data of an arbitrary observation point is compared with a first threshold, and the magnitude data of the blood flow velocity data of the observation point is compared with a second threshold, and the data of the observation point is The supercomputer is characterized by comprising means for obtaining composite image data by adding tomogram data or blood flow velocity data of a plurality of observation points determined to be tomogram data or blood flow velocity data, and displaying the composite image. Sonic diagnostic equipment. (2) In an ultrasonic diagnostic apparatus that obtains blood flow velocity data consisting of tomographic image data, size data, and angle data based on received signals obtained by transmitting and receiving ultrasound waves to and from a subject,
The size data and angle data of the blood flow velocity data,
Ultrasonic diagnosis characterized by comprising a conversion means for converting into brightness data, hue data, and saturation data using a matrix that varies according to the observation site of the subject, and displaying the size and direction of blood flow in color. Device. (3) The ultrasonic diagnostic apparatus according to claim 2, wherein the converting means converts size data into brightness data and converts angle data into hue data. (4) The ultrasonic diagnostic apparatus according to claim 2, wherein the converting means converts size data into saturation data and converts angle data into hue data. (5) The ultrasonic diagnostic apparatus according to claim 2, wherein the converting means converts size data into hue data and angle data into brightness data.