JPS5854941A - Ultrasonic diagnostic 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 The present invention relates to an ultrasonic diagnostic apparatus that emits ultrasonic pulses into a living body and displays cross-sectional images of tissues in the living body based on ultrasound echoes that are reflected waves thereof.

In general, in ultrasound diagnostic equipment, regardless of whether the electronic scanning method is sector type or linear type, the emission period of ultrasound pulses from the ultrasound probe is unique depending on the diagnostic depth of the subject. Determined by However, for example, the reflected wave (ultrasonic echo) of the nth ultrasonic pulse emitted from the ultrasonic probe may be interfered with by the residual ultrasonic echo based on the ultrasonic pulse emitted earlier. ,For this reason,
It was not possible to display a cross-sectional image of the object with a good sA ratio on the monitor screen.

Therefore, an object of the present invention is to provide an ultrasonic diagnostic apparatus that can control the emission period of ultrasonic pulses and obtain a cross-sectional image of a subject with a good sA ratio.

FIG. 1 is a block circuit diagram of one embodiment of the present invention.

The trigger signal generator 1 is connected to the pulser 2 and a trigger signal is applied to the pulser 2 via this connection. The pulse repetition period control circuit 3 is connected to the pulser 2.

The pulse repetition period control circuit 3 controls the electric pulses generated inside the pulser 2 in response to the application of a trigger signal to the pulser 2.
The signal that controls the timing output from the output section of
It is applied to the pulser 2 via the above connection. The above-mentioned timing is, for example, at a period such that the ultrasonic echo based on the nth ultrasonic pulse does not receive interference from the residual ultrasonic echo based on the (n-1)th emitted ultrasonic pulse, The timing may be set so that the ultrasonic pulse is emitted from the ultrasonic probe 4, or the timing may be set in consideration of interference from residual ultrasonic echoes based on ultrasonic pulses emitted earlier. In short, it is determined so that a good ultrasound diagnosis can be performed based on a cross-sectional image, a planar image, etc. of the subject, and can be arbitrarily varied.

The pulse repetition period control circuit 8 is also connected to the receiver 5 , and the ultrasound probe 4 is also connected to the receiver 5 . Therefore, through these connections, the receiver 5 converts the electric signal received by the ultrasonic probe 4 in synchronization with the application timing of the electric pulse applied from the pulser 2 to the ultrasonic probe 4. Ultrasonic echoes that are converted can be received. The display 6 is connected to the output section of the receiver 5 and displays a cross-sectional image of the subject based on the received output from the receiver 5. The storage circuit 7 is connected to the input section 6 , stores the received output from the receiver 5 , and outputs an electrical signal corresponding to the stored information to the display 6 . Therefore, the display device 6 can also display a cross-sectional image of the subject on the monitor screen included therein at once in response to the stored electrical signal from the storage circuit 7.

The operation of this embodiment will be explained with reference to FIGS. 2 and 3.

Is ultrasonic probe 4 a pulsa? Every time an electric pulse is applied from the in-vivo tissue 8, an ultrasonic pulse is emitted to the in-vivo tissue 8, as shown in FIG.

The emission period of this ultrasonic pulse is controlled by the pulse repetition period control circuit 3, as shown in FIG.
St2. ...5tn1S2, +5221"'+52n
v 5311S321"'1s3nlS4], S4□,
..., are controlled according to the order of S4n. The arrow bones shown in the figure indicate the traveling directions of the ultrasonic pulses and ultrasonic echoes.

The ultrasonic pulses thus emitted are sequentially received as ultrasonic echoes by the ultrasonic probe 4, where they are converted into electrical signals. The receiver 5 receives an electrical signal from the ultrasound probe 4 and outputs a received signal corresponding to the electrical signal to the display 6.

As shown in FIG.
A collection of over 100 horizontal scanning lines per frame.
configured. By displaying a large number of frames per second on the monitor screen, the operator can observe a cross-sectional image of the in-vivo tissue. In this embodiment, first, considering the many horizontal scanning lines within the first frame, the horizontal scanning lines containing the cross-sectional image information of the object are the ultrasonic pulses Sll, S12.
,..., get l =t21 corresponding to S4n...
・, 4, n. That is, ultrasonic pulse 511 + S
12 +..., ultrasonic echoes corresponding to S1n are received by the ultrasonic probe 4.

Then, the receiver 5 detects all the cross-sectional points of the in-vivo tissue 8.
, a+2, .
+..., point b1+ + b+2+... on 61n
・The brightness at b+n changes, and a part of the cross-sectional image of the in-vivo tissue 8 is displayed. Considering the next frame, this time the ultrasonic pulses S21, S22,
.-, the horizontal scanning line on the monitor screen corresponding to S2n is n21 + 1122 +..., #2n.

That is, in the same manner as described above, the cross-sectional point a21 of the in-vivo tissue 8 is
+ a22 +..., horizontal scanning lines 121, 12°,... on the monitor screen corresponding to a2n.

Point b21 on /2n. b+2. ..., the brightness at b2n changes, and thereby a part of the cross-sectional image of the in-vivo tissue 8 is displayed. Therefore, in this way, cross-sectional points of the in-vivo tissue are sequentially displayed on the monitor screen each time the frame changes, and eventually a cross-sectional image of the entire in-vivo tissue is displayed. The memory circuit 7 sequentially stores the received signals from the receiver 5, and when the received signals regarding the entire cross-sectional image of the in-vivo tissue are obtained, the memory circuit 7 derives the stored output all together on the display 6, and displays the stored output. This allows static cross-sectional images of in-vivo tissues to be obtained at once.

In addition, in the above embodiment, the period of the electric pulse applied from the pulser 2 to the ultrasound probe 4 can be changed arbitrarily, and this change may be performed automatically or , the operator may be able to change it while viewing the cross-sectional image of the subject on the monitor screen. In this manner, in the above-described embodiment, based on the cross-sectional image of the subject displayed on the monitor screen, the operator can further use the pulse The repetition period control circuit 8 is set and controlled to lengthen the emission period of the ultrasonic pulse corresponding to the specific portion, thereby making it possible to obtain a cross-sectional image with a good S/N ratio of the object to be observed.

As explained above, according to the present invention, the ultrasonic echo, which is the reflected wave of the ultrasonic pulse, receives interference from residual ultrasonic echoes, etc., and therefore, the S/'N ratio is improved. A cross-sectional image of the subject can be displayed on the monitor screen, and a desirable ultrasound diagnosis can be performed while observing a clear cross-sectional image of the affected area.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram of an embodiment of the present invention, and FIG. 3 is a diagram for explaining display of a cross-sectional image of a subject using horizontal scanning lines on a monitor screen. 1...Trigger signal generation circuit, 2...Pulser~, 3...
...Pulse repetition period control circuit, 4...Ultrasonic probe,
5...Receiver, 6...Display device, 7...Memory circuit agent Patent attorney Kazuhide Okada Figure 12

Claims (1)

[Claims] Emission from the ultrasonic probe to such an extent that the ultrasonic echo based on the nth ultrasonic pulse emitted is not affected by residual ultrasonic echoes etc. based on ultrasonic pulses emitted before the nth pulse. An ultrasonic diagnostic apparatus comprising: a circuit that drives and controls an ultrasonic probe periodically; and a circuit that receives electrical signals related to ultrasonic echoes and displays a cross-sectional image of a subject.