JPH01244738A - Ultrasonic diagnostic device - Google Patents

Abstract

PURPOSE:To improve the detecting ability of slow blood flow velocity and to visually recognize the information of the speed and power of a blood flow by converting the difference in the blood flow power corresponding to the difference in chroma saturation and simultaneously providing a color processing means to convert a difference in the blood flow velocity corresponding to the difference in brightness. CONSTITUTION:The change of a blood flow velocity V is made to correspond to the change of a saturation S by a color processing means 36a, and the difference in the blood flow velocity V is displayed by the difference in the chroma saturation S. Since the change of a blood flow power P is made to correspond to the change of the brightness I along with the information of the blood velocity V, the difference in the blood flow power P is displayed by the difference in the brightness I, and the information of the blood flow power P is also simultaneously displayed. Consequently, since the slow blood flow velocity and fast blood flow velocity are displayed with the same brightness I and the part of the slow blood flow velocity P is clearly displayed in a bright color so as to be easily seen, the velocity can be clearly recognized even at the place of the slow blood flow velocity, and the detecting ability of the slow blood flow velocity P can be improved. Since the change of the blood flow power P is displayed corresponding to the change of the brightness I, the information of both blood flow velocity V and blood flow power P can be visually recognized clearly, and diagnostic ability can be improved.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention is directed to obtaining a tomographic image of a subject from ultrasound echo information or a two-dimensional blood flow image using the Doppler effect of ultrasound, for example. Related to ultrasonic diagnostic equipment.

(Prior Art) An ultrasonic diagnostic apparatus transmits ultrasonic waves from outside the body and uses a two-dimensional image formed by the reflected waves to understand the tissue structure of the human body's details. It is also conventionally possible to determine the rate at which blood flows toward and away from each point in an image using pulsed Doppler techniques. An image of blood flow velocity distribution obtained by such a pulse Doppler method can also be superimposed on an image of a tissue structure. This velocity distribution was displayed in a gray hue, but with this method of displaying the velocity distribution, it was difficult to distinguish the flow velocity image from the tissue structure image.

The solution is to divide the velocity of blood flow in one direction into several velocity ranges, assign an arbitrary color from a group of colors to each division, and apply the same color to the velocity in the opposite direction. There was a similar way to assign colors. In this method of creating a velocity distribution map, the combination of a specific color and a predetermined flow velocity becomes unnatural. For this reason, the flow in one direction was displayed using one fixed hue of red, and the flow in the other direction was displayed using one fixed hue of stable blue. Furthermore, in this method, differences in blood flow velocity are converted to correspond to differences in brightness, and the images are displayed in color. In other words, with this display method, when the blood flow velocity is smaller than the threshold value, it is displayed in black, when the blood flow velocity is slightly larger than the threshold value, it is displayed in dark colors (red, blue), and when the blood flow velocity is slightly larger than the threshold value, it is displayed in black. The brightness increases as the blood flow rate increases, and a bright color (the color with the highest brightness) is displayed when the blood flow velocity is at its maximum. Note that in this display method, information on blood flow power is not displayed simultaneously with information on the self-flow velocity.

(Problems to be Solved by the Invention) As described above, the conventional display methods have the following problems. That is, when the blood flow velocity is slow, the color display becomes dark, making it difficult to see, and there is a problem in that it becomes difficult to detect slow blood flow. Furthermore, it has been desired to simultaneously display blood flow information such as blood flow velocity and blood flow power in clear color.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an ultrasonic diagnostic apparatus that can improve the ability to detect slow blood flow velocity and visually recognize both blood flow velocity information and blood flow power information.

[Structure of the Invention] (Means for Solving the Problems) The present invention takes the following measures to solve the above problems. In other words, in an ultrasonic diagnostic apparatus that displays a tomographic image of a subject based on the reflected components of ultrasound waves transmitted toward the subject, and displays blood flow information in color overlaid on this tomographic image, blood flow velocity is The apparatus includes color processing means for converting differences in color saturation in accordance with differences in color saturation, and converting differences in blood flow power in correspondence to differences in brightness.

Furthermore, in an ultrasonic diagnostic apparatus that displays a tomographic image of a subject based on reflected components of ultrasound waves transmitted toward the subject, and displays blood flow information in color overlaid on this tomographic image,
The apparatus includes color processing means for converting differences in blood flow velocity in accordance with differences in saturation and brightness.

(Effects) By taking such measures, the following effects are achieved. According to the present invention, a change in blood flow velocity is made to correspond to a change in saturation by the color processing means, and a difference in blood flow velocity is displayed as a difference in saturation. In addition to this Ith flow velocity information, since changes in blood flow power correspond to changes in brightness, differences in blood flow power are displayed as differences in brightness, and blood flow power information is also displayed at the same time. Therefore, even parts with slow blood flow speeds are displayed clearly and easily in bright colors, improving the ability to detect slow blood flow speeds, and making it possible to visually clearly recognize both blood flow speed and blood flow power image information. .

In addition, we expanded the color range by changing brightness and saturation in response to changes in blood flow direction and blood flow speed, so slow blood flow is expressed in vivid colors (the highest gradation of pure color). This makes it easier to visually see the velocity distribution, and even slow blood flow can be easily detected.

(Embodiment) FIG. 1 is a block diagram showing a first embodiment of an ultrasonic diagnostic apparatus according to the present invention. In FIG. 1, the ultrasonic diagnostic apparatus includes an electronic scanning ultrasonic probe (hereinafter referred to as "probe") 11, an electronic scanning device analog section 12, a 90'' phase shifter 25, mixers 24a and 24b.

Low-pass filters 26a, 26b, MTI
(MovingTarget indicator)
) arithmetic unit 27, scan conversion means (digital scan
converter) 34, 35, a color processing means 36, a multiplexer (MPX) 37, a D/A (digital/analog) conversion means 38, and a display means 39. The electronic scanning device analog section 12 includes a preamplifier 13.
Balsa 149 oscillator 15° delay line 16. It is configured to include an adder 17 and a detector 18.

One of the signals output from the adder 17 is sent to the scan conversion means 34 via the detector 18. The other signal is sent out from line 19 onwards, and this signal is input via line 19 to mixers 24a and 24b. The mixers 24a and 24b include a 90° phase shifter 2.
5, the reference signal to from the oscillator 15 is inputted so as to produce a phase difference of 90'. and mixer 24a,
24b, the signal from line 19 and the reference signal fO are mixed, and low-pass filters 26a,
26b I, - Doppler shift signals fd, 2fO+fd are input. Furthermore, a low pass filter 26a.

26b, the Doppler shift signal is a high frequency component.

2fO+f+j is removed and only the Doppler shift signal fd is output. This Doppler shift signal becomes a phase detection output signal for calculating blood flow information. Furthermore, the phase detection output signals outputted from the low-pass filters 26a and 26b are inputted to the MTI calculation section 27. This MTI driver section 27 includes A/D converters 28a and 28b.
, MTI filters 29a, 29b, autocorrelator 30, average speed calculation unit 31, variance 8II calculation unit 32,
It is configured to include a power calculation section 33. This MTI is an abbreviation for a moving target indicating device, which detects only moving targets using the Doppler effect. The autocorrelator 30 is one type of frequency analysis method, and is used because it is necessary to perform two-dimensional multi-point frequency analysis in real time.

In addition, the average velocity calculation section 31, the variance calculation section 32, and the power calculation section 33 each calculate the blood flow velocity 1 variance and power by executing predetermined calculations. MTI calculation unit 27
The output is sent to the color processing means 36 via the scan conversion means 35.
The image is taken in by the color processing means 36 and subjected to color processing. The color processing means 36 converts differences in blood flow velocity to correspond to differences in saturation, and also converts differences in blood flow power to correspond to differences in brightness. Note that dispersion and power are also color-processed as appropriate, but this processing is the same as in conventional devices. The output processed by the color processing means 36 and the converted output of the scan conversion means 34 are sent to the display means 39 via the MPX 37 and the D/A converter 38.

Next, color processing means 36a, MPX37. D/A
Details of the converting means 38 will be explained with reference to FIG. 2. As shown in the figure, the color processing means 36a is R0M40.
a to 42a, and the conversion output of the scan conversion means 35 is taken into each R0M 40a to 42a. The ROMs 40a to 42a input information on the direction and velocity of blood flow V and information on blood flow power P from the scan conversion means 35, and display them on the display means 39 in red (R), It converts into digital signals representing the brightness of green (G) and blue (B). In other words, this R
Display means 39 according to storage information of OMs 40a to 42a.
are displayed in various colors. ROfv140a~4
The storage information of 2a is determined as follows.

Fig. 3 (a) and (b) are diagrams showing the Munsell's )-ISf color system, and Fig. 3 (C) shows blood flow velocity ■ and blood flow power P corresponding to the H8I color system. FIG.

In the same figure, I (1 degree) is O≦I≦1, S (saturation) is O≦S≦1, and H (hue) is 0≦H≦360°.
shall be.

Now, as shown in the following formula, the above H, S, and I are the blood flow velocity ■
and the blood flow power P. Note that the blood flow velocity V is set to -1/2≦V≦1/2, and the blood flow power P is set to 0≦P≦1.

Here, when the blood flow velocity V is in the range of O≦V≦1/2, H=A S−2X (C−1)×V−+1 1=2×D×V+ExP.

Further, when the blood flow velocity V is in the range of -1/2≦V≦0, H=B S=2 X (1-C) xv+1 1=-2XDXV+EXP.

Note that the constants A and B are arbitrary constants from 0 to 360, and the constants C, D, and E are arbitrary constants from 0 to 1. For example, if the constant is C-0,5,D=0. When E-0,5 is specified, the brightness I increases as the blood flow power P increases from small to large. Also, if you specify constants A = 120° and B = 360°,
The blood flow velocity V flowing toward the observer changes from bright red to dull red, and the blood flow velocity V flowing away from the observer changes from bright blue to dull blue.

FIG. 4 is a diagram showing a zig graph. This ziggraph is a graph that converts H, S, and T corresponding to the blood flow velocity (1) and blood flow power P into R, G, and 8 signals. A conversion table is created in the ROMs 40a to 42a based on this ziggraph. Note that when the blood flow power P is 0 or less than a predetermined threshold value, the determination is made as follows.

R=G=B=O...(4) The MPX 37 is equipped with switches 43, 44, 45, and the switching operation of the switches 43, 44, 45 converts the output of the scan conversion means 34 (B mode image information), Each ROM 40a
A synthesis process with the output of ~42a is performed. The D/A conversion means 38 has D/A converters 4B, 47.48,
A converter 46, 47, 48 causes said switch 43.
The selection outputs of 44° and 45 are converted into analog signals, and these signals are sent to display means 39.

The ultrasonic diagnosis 4ifl configured in this way operates as follows. First, the electronic scanning device analog unit 12 scans the object to obtain a B-mode image, and the B-mode information obtained by this scanning is converted into display system scanning by the scan conversion means 34. D/A
It is sent to the display means 39 via the conversion means 38 and displayed in gradation.

On the other hand, the Doppler data collected at the same time as the B-mode image information collection is taken into the MTI calculation unit 27 via mixers 24a and 24b and low-pass filters 26a and 26b. This data is then stored in the average speed calculating section 319 in the MTI calculating section 27 and the variance calculating section 32. Power calculation section 33
A predetermined calculation is processed, and the calculation result is passed through the scan conversion means 35 to the color processing means 36, where different blood flow velocities V have different saturations (S of Mansen's H8I display system).
, different blood flow power P has different brightness (Munsell's H8I
It is converted into color information of display system 1). And this color information is MPX37. The signal is sent to the display means 39 via the D/A conversion means 38 and displayed superimposed on the B-mode image.

As described above, according to this embodiment, the color processing means 36a makes the change in the blood flow velocity (2) correspond to the change in the saturation S, and the difference in the blood flow velocity V is displayed as the difference in the saturation S. Also this lf
[In addition to information on flow velocity ■, changes in blood flow power P correspond to changes in brightness I, so differences in blood flow power P are displayed as differences in brightness ■, and information on blood flow power P is also displayed at the same time. Is displayed. Therefore, both slow and fast blood flow velocities are displayed with the same brightness I, and areas with slow blood flow velocities P are also clearly displayed in bright colors, making it easy to clearly see the speed even at slow blood velocities. and slow blood flow velocity P
Detection ability will be improved. In addition, since changes in blood flow power P are displayed in response to changes in brightness I, image information on both blood flow velocity V and blood flow power P can be visually recognized clearly, improving diagnostic ability. Can be done.

Next, a second embodiment of the present invention will be described. FIG. 5 shows color processing means 36b, MPX 37. 3 is a diagram showing details of a D/A converter 38. FIG. In this embodiment, the color processing means 36b is changed from the first embodiment, and the other parts have the same circuit configuration as in the first embodiment. As shown in the figure, the color processing means 36b is R0
Equipped with M40b, 41b, 42b, each RQM
40b, 41b, 42b are provided with the scan conversion means 3.
The conversion output of 5 is taken in, and the difference in blood flow velocity is converted into a difference in saturation and brightness. This R0M40b
, 41b, and 42b input information on the direction of blood flow and blood flow velocity from the scan conversion means 35, and display the information on the display means 39 in red (R), green (G), and blue (B).
This converts the brightness into a digital signal representing the brightness of the image.

That is, various colors are displayed on the display means 39 depending on the information stored in the ROMs 40b to 42b. ROM
The storage information of 40b to 42b is determined as follows.

FIGS. 6(a) and 6(b) are diagrams showing Munsell's 881 color system, and FIG. 6(C) is a diagram showing blood flow velocity V corresponding to the 881 color system. Now, it is assumed that the color changes in accordance with the blood flow velocity V, as shown by the thick line in FIG. 6(C). And R, B.

G is changed in accordance with the blood flow velocity as shown in the equation below. Note that the blood flow velocity V is 11/2≦V≦1/2.

Here, when the blood flow velocity ■ is in the range of 0≦V≦1/2, R=1 G-2(△-0,3) XVlo, 7B=2 (A
−0,3) xVlo, 7.

Moreover, when the blood flow velocity V is in the range of 11/2≦V≦O, R=2 (C-0,1) XVlo, 9G=2 (
C-0, 1) xVlo, 9[3=1.

Here, A and C are red color and the maximum brightness of the front nails, and are specified as, for example, Δ=o, e, and c=o, e. In the figure, α indicates the highest brightness display color with 100% saturation. and blood flow speed
The saturation S and the brightness I change with the change in . Based on this, a conversion table is formed in the ROMs 40b to 42b.

Furthermore, the display means 39 shows the velocity of blood flowing toward the observer V1. i AT is displayed as if changing from bright red to whitish red, and the blood flow velocity V moving away from the observer is displayed as changing from bright blue to whitish blue.

In this way, according to this embodiment, the color range is expanded by changing the brightness and saturation in response to changes in the direction of blood flow and its velocity, so that slow blood flow becomes bright ( The velocity distribution can be expressed in the highest gradation of pure color, making it easier to visually see the velocity distribution, and even slow blood flow can be easily detected.

Note that the present invention is not limited to the embodiments described above, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the present invention, a color processing means is provided which converts differences in blood flow velocity in accordance with differences in saturation, and converts differences in blood flow power in accordance with differences in brightness. Therefore, the ability to detect slow blood flow speed can be improved, and both blood flow speed information and blood flow power information can be visually recognized. In addition, the brightness and saturation are changed in response to changes in the direction of blood flow and the speed of blood flow, expanding the color range, so slow blood flow becomes vivid (!!!the highest gradation of color). It is possible to provide an ultrasonic diagnostic device that can be expressed as follows, the velocity distribution is visually easy to see, and even slow blood flow can be easily detected.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the first embodiment of the ultrasonic diagnostic 'rS device according to the present invention, Fig. 2 is a diagram showing details of the main parts of the device, and Fig. 3<a> and (b) are Munsell Explanatory diagram of color system,
Fig. 3 (C) is a diagram showing blood flow velocity and blood flow power corresponding to the H3I color system, Fig. 4 is an explanatory diagram showing a list of H8I-RGB conversion formulas, and Fig. 5 is a diagram showing the H8I-RGB conversion formula. Figures showing details of the main parts in the example, Figures 6(a) and 6(b) are explanatory diagrams of the Munsell color system, and Figure 6(C) shows blood flow velocity corresponding to the H81 color system. It is a diagram. 11... Ultrasonic probe, 27... MTI calculation unit,
34°35...Scan conversion means, 36a, 36b.
...Color processing means. Applicant's agent Patent attorney Takehiko Suzue Figure 2 Figure 5! (b) Figure 6

Claims (2)

[Claims] (1) In an ultrasonic diagnostic device that displays a tomographic image of a subject based on the reflected components of ultrasound waves transmitted toward the subject, and displays blood flow information in color superimposed on this tomographic image, An ultrasonic diagnostic apparatus characterized by comprising color processing means that converts differences in blood flow velocity to correspond to differences in saturation, and converts differences in blood flow power to correspond to differences in brightness. (2) In an ultrasonic diagnostic device that displays a tomographic image of a subject based on the reflected components of ultrasound waves transmitted toward the subject, blood flow information is displayed in color overlaid on this tomographic image. An ultrasonic diagnostic apparatus characterized by comprising color processing means for converting differences in flow velocity to correspond to differences in saturation and brightness.