JPH078484A - Ultrasonic doppler diagnostic device - Google Patents

Abstract

PURPOSE:To display the waveform of Doppler signal at an arbitrary position without increasing the storage capacity after the Doppler signal is taken in. CONSTITUTION:An average speed signal to be outputted from a Doppler arithmetic circuit 16 is stored in a speed memory 20 and a distributed signal 102 is stored in a distributed memory 22. The memories 20 and 22 store average speed information or distributed information on each position of the two-dimensional Doppler picture for plural frames. A Doppler signal reproducing circuit 24 reads out the average speed information and the distributed information in time series corresponding to the position when some position to be reproduced is designated, and forms the reproduced Doppler signal by synthesizing them.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic Doppler diagnostic apparatus, and more particularly to an ultrasonic Doppler diagnostic apparatus which two-dimensionally displays the average velocity and dispersion of moving bodies in a living body.

[0002]

2. Description of the Related Art An ultrasonic Doppler diagnostic apparatus displays an average velocity of a moving body such as a blood flow in a living body and a dispersion of the velocity. The conventional ultrasonic diagnostic apparatus disclosed in Japanese Patent Publication No. 62-44494 will be described below.

The ultrasonic waves transmitted into the living body by the ultrasonic probe undergo a so-called Doppler shift when reflected by a moving body (motion reflector) in the living body. The reflected wave that has undergone the Doppler shift is received by the ultrasonic probe, becomes a received signal, is orthogonally detected by the orthogonal detection circuit (complex signal conversion circuit), and only the Doppler shift information is extracted. The signal (Doppler signal) is subjected to an autocorrelation operation in an autocorrelator, and the average velocity of the moving body and the variance of the velocity are obtained from the autocorrelation result (for the variance operation, see, for example, Japanese Patent Publication No. 2-39254). ).

The obtained speed information is the Japanese Examined Patent Publication No. 64-77.
As shown by 85 and the like, the red and blue colors are discriminated depending on whether the velocity is positive or negative, and the images are displayed overlaid on the tomographic image.
If you want to display the velocity dispersion information at the same time,
Other colors are mixed with blue. It is displayed according to the degree of color mixing.

In the conventional apparatus, when it is desired to view the Doppler information of an arbitrary point in a two-dimensional Doppler image as a waveform instead of a color display (waveform display of Doppler signal), a cursor is previously set on the displayed tomographic image. Specify the position with. After that, when Doppler diagnosis is executed,
Separately from the two-dimensional tomographic image and the two-dimensional Doppler image, the waveform of the Doppler signal at the designated position is displayed at a predetermined position in the display image.

Incidentally, in the above Japanese Patent Publication No. 64-7785, the relationship between the Doppler signal waveform and the average velocity and dispersion is illustrated.

[0007]

Therefore, in the prior art, when the display of the Doppler signal waveform is desired, the position must be designated in advance and the Doppler signal itself at that position must be extracted and stored. After the completion of the image, it was not possible to freely reproduce the Doppler waveform at an arbitrary position.

Here, it is possible to store the Doppler waveform itself at all positions for a certain period, but in that case, the frame rate is lowered and a huge storage capacity is required, so that it is not realistic. Absent.

The present invention has been made in view of the above-described conventional problems, and an object thereof is to reproduce a waveform corresponding to a Doppler signal at an arbitrary position after capturing Doppler information while suppressing the storage capacity to a certain limit. An object is to provide an ultrasonic diagnostic apparatus.

[0010]

In order to achieve the above object, the present invention provides an average velocity calculation circuit for calculating an average velocity of a moving body in a living body from a received signal and a velocity of an in-vivo moving body from a received signal. A dispersion calculation circuit that calculates the dispersion and a display that displays a two-dimensional Doppler image that represents the distribution state of the average velocity and the dispersion, and a supercapturing motion information of a moving body in a living body by transmitting and receiving ultrasonic waves. In a sound wave Doppler diagnostic device, for each position in the two-dimensional Doppler image, a speed information storage circuit that stores the calculated average speed over a plurality of frames, and for each position in the two-dimensional Doppler image, the calculated A dispersion information storage circuit for storing dispersion over a plurality of frames, a position designating circuit for designating a reproduction position in the two-dimensional Doppler image, and the average velocity storage circuit. And a Doppler signal reproduction circuit that reproduces the Doppler signal by reproducing the average velocity and the dispersion stored for the reproduction position in time series order from the dispersion storage circuit, and synthesizing them to reproduce the Doppler signal. The Doppler signal is displayed.

[0011]

According to the above configuration, when the Doppler information is captured, the average velocity and the variance for each position of the two-dimensional image are stored for a plurality of frames as the two-dimensional Doppler image is displayed. After the acquisition of the Doppler information, if the reproduction position is specified, the average velocity and variance at that position are read out, and by combining them, the Doppler signal waveform (to be exact, approximate or simulated Doppler Signal waveform) is reproduced and displayed on the display.

Since the average velocity indicates the average level of the Doppler signal, and the variance indicates the spread of the velocity, an approximate signal form can be specified with these two data, and as a result, an enormous memory is stored. The Doppler signal can be reproduced after the acquisition of the Doppler information without requiring a capacity.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the overall configuration of an ultrasonic Doppler diagnostic apparatus according to the present invention.

The ultrasonic probe 10 is, for example, in contact with the surface of a living body to transmit and receive ultrasonic waves. A transmission drive signal is supplied from the transmission / reception circuit 12 to the ultrasonic probe 10, and the ultrasonic wave radiated from the probe 10 is reflected at each point in the living body and is transmitted by the probe 10. Received. Here, the reflected wave reflected by the moving body in the living body undergoes so-called Doppler shift.

The received signal output from the probe 10 is subjected to processing such as amplification and detection by the transmission / reception circuit 12 and then becomes a tomographic image signal 100 to a digital scan converter (hereinafter referred to as DSC) 14. Has been sent. This DS
C14 is for forming an ultrasonic image, and specifically includes a frame memory and has functions such as coordinate conversion and image synthesis.

The transmission / reception circuit 12 is provided with a detection circuit for obtaining the tomographic image signal 100 and a quadrature detection circuit for extraction of Doppler information. The complex signal generated by the quadrature detection is sent to the Doppler operation circuit 16. Has been sent. The Doppler arithmetic circuit 16 obtains velocity information of the in-vivo moving body by calculating the autocorrelation between the received signals. The obtained speed is averaged and sent to the DSC 14 as an average speed signal 102. The velocity dispersion is sent to the DSC 14 as a dispersion signal 104.

The DSC 14 creates a black-and-white tomographic image based on the tomographic image signal 100, superimposes a color Doppler image based on the average velocity signal 102 and the dispersion signal 104 on it, and outputs it to the display 18 as image information.

Conventionally, the Doppler arithmetic circuit 16 outputs the Doppler signal 106 to the DSC 14 in order to monitor the Doppler signal at a specific position on the tomographic plane as a waveform. The Doppler signal 106 is a signal before averaging the speed information. However, in the ultrasonic diagnostic apparatus of the present embodiment, since the Doppler signal reproduction circuit described in detail later is provided, it is necessary to specify the observation point of the Doppler signal in advance and store the acquisition of the Doppler signal at the observation point. Moreover, it is possible to reproduce the waveform of the Doppler signal at an arbitrary point after capturing the Doppler information.

The configuration described above is almost the same as the configuration of the conventional ultrasonic Doppler diagnostic apparatus, and the characteristic configuration of the ultrasonic Doppler diagnostic apparatus of the present invention will be described below.

The average speed signal 102 output from the Doppler arithmetic circuit 16 is supplied to the speed memory 20. The speed memory 20 stores the average speed for a plurality of frames over the entire two-dimensional Doppler image. That is, the speed memory 20 is configured in a so-called ring buffer format, and stores the average speed at each position for the number of frames, for example, about ten seconds.

On the other hand, the distributed signal 104 output from the Doppler arithmetic circuit 16 is supplied to the distributed memory 22 in the same manner as described above, and the distributed information for a plurality of frames is stored over the entire two-dimensional Doppler image.

By the way, if the Doppler signal 106 is stored as a waveform for each point of the two-dimensional Doppler image for a dozen seconds, a very large storage capacity is required, but according to the apparatus of this embodiment, it is about 8 Kbytes. Information that constitutes the Doppler signal can be stored with the storage capacity.

When a certain position in the two-dimensional Doppler image is designated, the Doppler signal reproducing circuit 24 reads the average velocity information and the variance information stored in the memories 20 and 22 for the position in time series order. To synthesize.

FIG. 2 shows the synthesized reproduced Doppler signal 20.
0 is shown. A line passing through the center of the waveform is the average velocity 202, and a line 204 as dispersion information is displayed above and below the line of the average velocity 202 as the center. The space between the two lines 204 can be filled with a predetermined color, for example. The wider the two lines 204 are, the larger the dispersion is. Of course, such a waveform is not the Doppler signal itself, but it can provide useful information for diagnosis by expressing the essential information contained in the Doppler signal in an easily understandable manner.

As the Doppler signal reproduced by using the average velocity information and the variance information, various types other than such a display form can be adopted.

In FIG. 1, the position designation device 26 is a device for moving the cursor displayed on the screen, and is composed of, for example, a trackball or the like. The reproduction control circuit 28 performs memory reading and control of the Doppler signal reproduction circuit 24 in accordance with the position designated by the position designation device 26.

The reproduced Doppler signal 200 output from the Doppler signal reproduction circuit 24 is sent to the DSC 14, and further sent to the display 18 to display its waveform.

FIG. 3 shows an example of a display screen displayed on the display unit 18. In FIG. 3, a fan-shaped 301 is an ultrasonic image, and a color Doppler image is superimposed and displayed on a black and white tomographic image. In the figure,
Reference numeral 302 denotes a cursor, which is the position specifying device 2 shown in FIG.
6, the cursor 302 can be moved freely, whereby the position where the waveform reproduction of the Doppler signal is required can be specified. In the figure, reference numeral 303 denotes an area in which the waveform of the reproduced Doppler signal is displayed, and for example, the reproduced Doppler signal shown in FIG. 2 is displayed.

In the ultrasonic Doppler diagnostic apparatus of this embodiment, the velocity memory 20 stores the average velocity information of each position in the two-dimensional Doppler image within a fixed period, and the distributed memory 22 stores the two-dimensional within a fixed period. Since the dispersion information of each position in the Doppler image is stored, it is possible to specify the observation point and display the waveform of the reproduced Doppler signal even after the Doppler information is captured. Therefore, for example, when performing ultrasound diagnosis of the heart, if you want to see the Doppler signal at a specific position, first freeze the movement of the ultrasound image by pressing the freeze switch,
After that, the position specifying device 26 is used to specify a desired position with the cursor, and the reproduction execution switch is input, whereby the average speed information and the dispersion information are read out from the predetermined addresses of the two memories, and are combined. Thus, the reproduced Doppler signal is displayed on the display. Also, after displaying the reproduced waveform of the Doppler signal at a certain point, you can move the cursor to reproduce the Doppler signal at another position. There is an advantage that the waveform of can be freely displayed.

[0030]

As described above, according to the present invention,
The Doppler signal can be reproduced after the acquisition of the Doppler information without requiring a huge storage procedure.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing a reproduced Doppler signal.

FIG. 3 is an explanatory diagram showing a display example.

[Explanation of symbols]

 20 speed memory 22 distributed memory 24 Doppler signal reproduction circuit 26 position specification device 28 reproduction control circuit

Claims (1)

[Claims] 1. An average velocity calculation circuit for calculating an average velocity of a moving body in a living body from a received signal, a dispersion calculation circuit calculating a variance of velocity of a moving body in a living body from a received signal, and the distribution of the average velocity and the dispersion. A display for displaying a two-dimensional Doppler image representing a state, and, in an ultrasonic Doppler diagnostic apparatus that captures motion information of a moving body in a living body by transmitting and receiving ultrasonic waves, for each position in the two-dimensional Doppler image A velocity information storage circuit that stores the calculated average velocity over a plurality of frames; a dispersion information storage circuit that stores the calculated dispersion over a plurality of frames for each position in the two-dimensional Doppler image; A position specifying circuit for specifying a reproduction position in the Doppler image, and the average speed storage circuit and the distributed storage circuit are used to identify the reproduction position. A Doppler signal reproduction circuit that reproduces the Doppler signal by reproducing and synthesizing the stored average velocity and dispersion in time series order, and the reproduced Doppler signal is displayed on the display. Ultrasonic Doppler diagnostic device.