JPH0716494B2 - Ultrasonic diagnostic equipment - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to an ultrasonic diagnostic apparatus that obtains a tomographic image in a living body by receiving reflected waves of ultrasonic waves that have entered the living body.

[Prior art]

Conventionally, an ultrasonic diagnostic apparatus capable of imaging blood flow information in the heart by pulse Doppler method has been used. Such an ultrasonic diagnostic apparatus is provided with a digital image memory and freezes (freezes) by storing an image in an arbitrary time phase among images continuously obtained in a moving image manner in this memory. You can do it. That is, when the operator presses the button at any time while observing the tomographic image displayed in a moving image manner, the image at that time is frozen and displayed as a still image.

[Problems to be Solved by the Invention]

However, when trying to freeze the image of the blood flow in the heart, the movement of the valve of the heart is very fast, and it is quite difficult to freeze the image of the desired time phase. Of course, if the images obtained sequentially in time are directly displayed on the video tape recorder or the like, the above problem can be solved, but the real-time property is lost. An object of the present invention is to provide an ultrasonic diagnostic apparatus improved so that an image of a subject moving at high speed can be easily frozen at a desired time phase of an operator without sacrificing real-time property. And

[Means for solving problems]

An ultrasonic diagnostic apparatus according to the present invention comprises means for transmitting ultrasonic waves into a subject, means for receiving ultrasonic waves from within the subject, means for forming an image from the received signals, and sequentially for each sampling time. A plurality of image storage means for always storing the obtained image up to a plurality of sampling points before the present time, and the storage operation of the image storage means by an image freeze operation at an arbitrary time ends after a plurality of sampling periods from that time point. And a means for fixing the stored contents.

[Action]

An image storage unit capable of storing a plurality of images is provided, and thus, an image slightly before the present time (that is, obtained at each of a plurality of sampling points immediately before the present time) is always stored. If the operator performs a freeze operation at any time, from that time until a plurality of sampling periods, the image storage operation is being performed as it is, and when a plurality of images are stored from that time, the image storage operation is terminated, The memory contents are fixed. That is, a plurality of images obtained at several sampling points before and after the freeze operation by the operator are stored and fixed. Therefore, even if the operator's operation is delayed for a while, or conversely, it is a little too fast, the images are stored in several images before and after the operation. You can get an image of.

【Example】

The figure shows an embodiment of the present invention. In the figure, an ultrasonic transducer 2 is brought into close contact with the surface of a subject (patient body) 1. A pulse-shaped ultrasonic drive signal is sent from the wave sending circuit 3 to the ultrasonic transducer 2, and the ultrasonic wave is sent into the subject 1. The reflected wave that returns by being reflected in the subject 1 of this ultrasonic wave is received by the transducer 2, and the received signal is guided to the wave receiving circuit 4 to obtain an image signal. This image signal is sent to the image display device 5 and displayed on its display screen. Therefore, pulse ultrasonic wave transmission and reception are repeated for each short sampling period to sequentially obtain images, which are displayed on the image display device 5.
If it is displayed with, a moving image will be displayed. On the other hand, the image signal from the wave receiving circuit 4 is sent not only to the image display device 5, but also to the digital image memory 6 capable of storing a plurality of images. In this image memory 6, for example, an image at a certain time is stored in the image memory for one image, and when a new image is obtained at the next time, the stored image is stored in the image memory for the next one image. By a sequential feeding method such as a shift register in which a new image is sent to store the new image, a plurality of images up to a moment before the present time are always stored in each of the image memories for the plurality of images. The control circuit 7 controls writing and reading of the image memory 6, and when the freeze button is pressed by the operator at an arbitrary time point, a write-inhibit signal is issued after a plurality of images are newly stored from that time point. put out. Therefore, the image memory 6 stores several images before and after the freeze button is pressed, and they are fixed as they are. Therefore, the operator presses the freeze button to freeze the moving image that was being displayed on the image display device 5 at that time to display it as a still image, and to store several images before and after that time stored in the image memory 6. It is possible to display still images one by one like reading frame feed one after another, and select a desired one from those. Therefore, even if the timing of pressing the freeze button is slightly deviated, the still image of the required time phase can be displayed on the image display device 5 in real time.

【The invention's effect】

According to the ultrasonic diagnostic apparatus of the present invention, it is possible to easily freeze a desired time phase image and obtain a still image in real time even in the case of a fast moving subject.

[Brief description of drawings]

The figure is a block diagram of an embodiment of the present invention. 1 ... Subject, 2 ... Ultrasonic transducer, 3 ...
Transmitting circuit, 4 ... Receiving circuit, 5 ... Image display device, 6 ...
… Image memory, 7… Control circuit.

Claims (1)

[Claims] 1. A means for transmitting an ultrasonic wave into a subject, a means for receiving an ultrasonic wave from within the subject, a means for forming an image from the received signal, and an image sequentially obtained at each sampling time. , The image storage means for a plurality of images, which is always stored until a plurality of sampling points from the present time, and the storage operation of the image storage means is terminated after a plurality of sampling periods from that point by an image freeze operation at an arbitrary point And a means for immobilizing the ultrasonic wave.