JPS6214837A - Ultrasonic blood flow imaging apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an ultrasonic blood flow imaging apparatus that displays blood flow information within a subject in two-dimensional color.

[Technical background of the invention and its problems] Conventionally, in the field of ultrasonic diagnosis of the circulatory system, etc. of a subject, an ultrasonic blood flow imaging device that displays blood flow information in the circulatory system, etc. in two-dimensional color has been used. exist.

FIG. 4 shows an example of a display in such an apparatus, in which a tomographic image 1 of a subject is displayed in black and white, and color information indicating changes in the velocity of blood flow 2 is displayed in this tomographic image 1. Ru. Further, a color bar 3 is also displayed on the same screen at the same time, and blood flow information can be recognized from the contrast between the color of the color bar 3 and the color of the blood flow 2. Normally, the color bar 3 indicates a change in the blood flow velocity (■) by a color change in the horizontal direction (blue-cut red), and a change in the degree of dispersion (disturbance of the average velocity) σ2 by a color change in the vertical direction.

However, with this kind of display, it is extremely difficult to accurately confirm the areas where the flow is equal in blood flow 2 (hereinafter referred to as "uniform flow areas"). This poses a problem in determining the degree of

[Purpose of the Invention] The present invention has been made in view of the above circumstances, and its purpose is to provide an ultrasonic blood flow imaging device that can accurately and easily confirm uniform flow velocity regions of blood flow. It is about providing.

[Summary of the Invention] The outline of the present invention for achieving the above object is to calculate the average velocity of blood flow from the echo component from the subject of ultrasound transmitted toward the subject, and In an ultrasonic blood flow imaging device that displays average velocity in color,
A speed input section into which a desired blood flow velocity can be input, and a color corresponding to the blood flow velocity inputted by this velocity input section are converted into a color that can be distinguished from adjacent colors on the display screen. The present invention is characterized by comprising a color conversion unit that can set constant flow velocity lines of blood flow on the screen.

[Embodiments of the invention] Hereinafter, the present invention will be specifically explained with reference to Examples.

FIG. 1 is a block diagram showing the main parts of an ultrasonic blood flow imaging apparatus according to an embodiment of the present invention.

4 shows an ultrasonic transmitting and receiving section, which includes an ultrasonic probe 5 that transmits and receives ultrasonic waves, a transmitting means 6 that outputs a transmission pulse to drive the ultrasonic probe 5, and an ultrasonic wave detected by the ultrasonic probe. and receiving means 7 for receiving the echo signal. Further, 8 is a phase detection section that phase-detects the echo signal received by the receiving means 7, 9 is a low-pass filter that removes unnecessary frequency components from the output of this phase detection section 8, and 10 is the output of this low-pass filter 9. 11 is an A/D (analog-to-digital) converter that converts the signal into a digital signal, and 11 is an M that subtracts an echo signal from a region that moves very slowly (for example, the heart wall).
A TI filter, 12 is an average velocity calculation unit that calculates the average velocity of blood flow from the output of the MTI filter 11, and 13 is a DSC (digital 14 is a color conversion unit that converts the output of the DSC 13 into a color signal, and also converts the color at the blood flow velocity input by the velocity input unit 16, which will be described later, to white;
A display section 15 displays blood flow information based on the color signal output from the color conversion section 14. Incidentally, a tomographic image created by a tomographic image processing section (not shown) is also displayed on this display section.

The speed input section 16 is for inputting the blood flow speed that is set to white in the color conversion section 14, and is provided with a speed setting means 17 for setting the blood flow speed, and a speed setting means 17 for setting the blood flow speed. and a variable resistor 18 that continuously varies the blood flow velocity.

Next, the operation of the embodiment device configured as above will be explained.

The ultrasound probe 5 is excited by the transmission pulse output from the transmission means 6, and thereby the ultrasound pulse is transmitted toward the subject. Ultrasonic echoes from the subject are received by the ultrasound probe 5 and then received by the receiver 7. The echo signal received by the receiving section 7 is phase-detected by the phase detection section 8, inputted to the A/D converter 10 via the low-pass filter 9, converted into a digital signal, and then averaged via the MTI filter 11. Speed calculation section 1
2 is input. Then, the average speed calculation unit 12 calculates the MT
The average speed of blood flow is calculated from the output of the I filter 11.

As is well known, the average velocity of the blood flow can be determined by calculating the average value of the Doppler shift frequency using, for example, an autocorrelation method, and using the calculation result. The average value fd of the Doppler shift frequency can be calculated using the following equation.

fd = (f r/2π) -tan-'(Σ(Xi
Yi, 1-Yi xi+1 > )/(Σ(Xi
i, 1+Yi Yi, 1') ) ... (1) Here, fr is the ultrasound pulse repetition frequency, X.

Y indicates phase detection outputs whose phases are shifted by 90' from each other. Since the average value fd of the Doppler shift frequency and the average blood flow velocity ■ have the following relationship, the average blood flow velocity ■ can be calculated from this relationship.

fd = (2V(CO3θ)fo)/c...
・(2) Here, C is the sound speed of 1500 m/s.

The calculated blood flow average velocity is then input to the color converter 14 via the DSC 13, where it is color-converted.

When a desired blood flow velocity is input by a doctor or the like via the velocity input section 16, the color conversion section 14 converts the blood flow velocity into (
Convert the input color to white. In other words, as shown in Figure 2, if the average velocity from the DSC 13 can vary within a range of ±15 with O as the center, the average velocity of the blood flow will vary from black to red in response to this change. or blue, and the color is converted to a different luminance. However, if the speed input unit 16 sets a blood flow velocity of +8, for example, the color conversion unit 14 converts the entire area at the average blood flow velocity +8. The reason for converting to white is to clearly distinguish the average velocity of blood flow from the original colors (red, blue).Therefore, colors that can be distinguished from adjacent colors on the display screen. If so, it may be converted to a color other than that of the song.

The blood flow information color-converted in this way is displayed on the display section 15.
is displayed in color. FIG. 3 shows an example of the display on the display unit 15, in which the constant flow line 19 is displayed in white on the blood flow 2, and the color bar 3 also shows the blood to which the constant flow line 19 is set. A constant flow line marker 20 is displayed in white corresponding to the flow velocity. The constant flow velocity line 19 indicates a constant flow velocity region of blood flow.

Therefore, doctors etc.
It is possible to more accurately and easily confirm the uniform flow velocity area,
By setting this constant flow velocity line 19 to an abnormal blood flow velocity, it becomes possible to intuitively determine the severity of the subject based on the area of the abnormal blood flow site.

Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above-mentioned embodiment, and can be modified as appropriate within the scope of the gist of the present invention.

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to provide an ultrasonic blood flow imaging device that can accurately and easily confirm a constant flow region of blood flow information.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the main parts of an ultrasonic blood flow imaging device that is an embodiment of the present invention, and FIG. 2 is an explanatory diagram for explaining the action of the color conversion section in the device of this embodiment.
FIG. 3 is an explanatory diagram showing an example of the display in the device of this embodiment, and FIG. 4 is an explanatory diagram showing an example of the display in the conventional device. 14... Color conversion section, 16... Speed input section.

Claims (1)

[Claims] In an ultrasonic blood flow imaging device that calculates the average velocity of blood flow from the echo component from the subject of ultrasound waves transmitted toward the subject and displays the calculated average velocity of blood flow in color, the desired blood flow is detected. A speed input section where speed can be input;
By converting the color corresponding to the blood flow velocity input by this speed input section into a color that can be distinguished from adjacent colors on the display screen, it is possible to set a constant flow velocity line of blood flow on the display screen. An ultrasonic blood flow imaging device comprising: a conversion section.