JPH021250A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

PURPOSE:To display not only a region impossible to display heretofore but also a region desired to be diagnosed at the center of a picture and to further display a display start depth along with an image by making the display start depth of an ultrasonic wave variable and allowing a display start point to coincide with one end part corresponding to the depth direction of an object to be examined of the display region of a display means. CONSTITUTION:The pulse width TMW from the output terminal Q of a monostable multivibrator 1 is set so as to be equal to or more than the pulse width TSW of a synchronous signal. When the resistance value of a variable resistor 1d is set to zero, TMW=TSW is formed and, when said resistance value is other than zero, TMW>TSW is formed. X-sweeping is performed from the left to the right on a display picture and Y-sweeping is performed from upper to below thereon and, when an image is displayed on the total display picture, the tomographic image of living body tissue 16 within a definite distance from the surface of a vibrator 7 as a display start depth is displayed on the display picture in the case of TMW = TSW and the surface of the vibrator, that is, the surface of the body of an examinee is displayed so as to be allowed to coincide with the upper end of the display picture. In the case of TMW = TSW, a certain depth part going to the interior of the examinee from the surface of the vibrator corresponding to the difference between TMW, TSW is allowed to coincide with the upper end of the display picture and, on the basis thereof, the tomographic image of the living body tissue 16 within a definite distance is displayed on the display picture.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention enables the display start depth of an ultrasonic tomographic image, etc. displayed on a CRT display screen to be easily and easily variably set. The present invention relates to an ultrasonic diagnostic apparatus in which the following information is displayed on a CRT display screen.

[Conventional technology]

In ultrasonic diagnostic equipment, the reflected ultrasonic waves for each ultrasonic wave transmitted from the transducer into the subject are displayed as images on the CRT monitor using A-mode, B-mode, M-mode, etc. However, until now, the display start depth on the display screen has been fixed, and only images within a certain range can be displayed based on this depth. In other words, the body surface of the subject that the probe touches is positioned at the top of the display area of the CRT display screen, and then the inside of the subject is displayed downward, so that the body surface is always visible. It was fixed at the top of the display area.

[Problem to be solved by the invention]

Therefore, even if the image display magnification is variable in conventional devices, if the observer sets the display magnification in the direction of enlarging the image, the thickness of the display screen is constant and the body surface is Because it is fixed to the top of the display area, the display range is restricted and some parts of the image cannot be displayed (deep parts protrude from the display area), and conversely, if you try to display the entire image, The entire image is displayed in a reduced size state, making it impossible to display minute details.

Furthermore, when making a diagnosis by bringing the probe into contact with the subject through an ultrasonic propagation medium such as an ice bag, most of the display area is occupied by the ice bag, and the necessary image of the subject is It has the problem of becoming too small.

The present invention has been made in view of the above-mentioned problems, and it is possible to make the display start depth of ultrasonic waves variable and match the display start point to one end of the display area of the display means corresponding to the depth direction of the subject. The purpose of the present invention is to provide an ultrasonic diagnostic apparatus that can display parts that could not be displayed in the previous system, display the part that is truly desired to be diagnosed in the center of the screen, and display the display start depth along with the image. do.

[Means to solve the problem]

The above problem is to transmit ultrasonic waves from an ultrasonic transducer into a subject, and receive the reflected echo signal by the transducer,
In an ultrasonic diagnostic apparatus that modulates the brightness of the received signal and displays it as an ultrasonic image in a predetermined area of a display means, the display area of the display means is arranged from a certain depth to one end corresponding to the depth direction of the subject. display start depth setting means for displaying the ultrasonic image on the display means as a variable depth; and display start depth display means for displaying the display start depth of the ultrasonic image on the display means together with the ultrasonic image. This is solved by

[Operation] When displaying an echo signal received by an ultrasonic transducer, in a normal display method, the transducer surface is aligned with one end of the display area of the display means corresponding to the depth direction of the subject, for example, the upper end. In contrast, the display start depth setting means matches the position at a certain depth from the vibrator surface to the one end, and displays the deeper part toward the other end. In other words, the ultrasonic image is not displayed from the depth position (the zero depth point is shifted outside the display area, but it is displayed from the middle depth). Also, it becomes possible to display parts that are not displayed, and it also becomes possible to display a part where an abnormality is recognized in the center of the display screen.

The display start depth display means displays the display start depth together with the ultrasonic image when the display start depth setting means controls the display means, so that the upper end of the displayed ultrasonic image is covered. Displays the depth from which the image is displayed within the specimen. This makes it easy to see the display start depth at a glance at the image on the CRT screen, and when diagnosing the image after photographic imaging, from what depth inside the subject's body is the image taken? Is it?
- It's easy to see and very convenient.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the present invention will be described with reference to FIG. 2 and FIG.

FIG. 1 is a block diagram of an example of an ultrasound diagnostic apparatus according to the present invention. In the figure, reference numeral 1 denotes a monostable multi-high break, and the main body 1a of the monostable multi-high break is provided with a time constant circuit consisting of a capacitor 1b, a fixed resistor 1c, and a variable resistor 1d. Reference numeral 2 denotes a NAND gate, 3 an inverter, 4 a synchronizing signal generating circuit, and 5 a high voltage pulse generating circuit which generates high voltage pulses in response to a synchronizing signal generated by the synchronizing signal generating circuit 4.

6 is a switch that supplies high voltage pulses from the high voltage pulse generation circuit 5 to the transducer 7, the transducer 7 transmits ultrasonic waves to the subject 16, and the echo signal received from within the subject is sent to the amplifier 8.
The output is switched to .

9 is a detection circuit, 10 is a video signal synthesis circuit, and amplifier 8
, the echo signal amplified and detected by the detection circuit 9 is converted into a video signal (luminance modulation signal), and the video signal synthesis circuit 10 is supplied with display start depth data, which will be described later, and is synthesized with the echo signal. It looks like this. 11
is an XY sweep circuit, 12 is a display numerical data generation circuit, 13 is
is an AND gate, 14 is a counter, and 15 is C
It is RT.

Next, the display start depth setting means will be explained in detail.

In this embodiment, a case will be described in which a monostable multi-high break is used as the display start depth setting means.

That is, the display start depth is set by adjusting the time constant of a time constant circuit forming a part of the monostable multi-high break l. As shown in the figure, a capacitor ib, a fixed resistor 1c, and a variable resistor 1d that constitute a time constant circuit are externally attached to the monostable multi-bi break main body 1a as an IC, and the monostable multi-bi break 1 is displayed by this variable resistor 1d. It is designed to function as a starting depth setting means.

By the way, the synchronization signal generation circuit 4 generates a so-called low level state (Y direction) synchronization signal with a period T as shown in FIG.
is triggered at the time of transition to the low level state. This makes the Q of monostable multi-high break 1
From that point on, a high-level pulse signal is obtained from the output terminal as shown in FIG.
This is considered to be the above. When the resistance value of the variable resistor 1d is set to zero, T, W=Ts, and when the resistance value is other than zero, T>TIW. By the way, the Nant gate 2 and the inverter 3 have the above-mentioned difference in pulse width, that is,
This is to detect the TMW-TSW as shown in FIG. 2(d), and the XY sweep circuit 11 controls the CRT 15 in the X direction and Y direction depending on the magnitude of the detected pulse width difference. Sweep start is controlled. That is, if the difference is zero, the display start depth is zero, that is, assuming that there is no delay in the start of the sweep, the Y direction sweep is almost synchronized with the time when the synchronization signal transitions to the high level state, and the X direction sweep is This is done in synchronization with a direction synchronization signal. However, if the difference is other than zero, both sweeps are started with a time delay corresponding to the magnitude of the deviation. FIG. 2 tel shows the Y direction sweep signal controlled as described above. In addition, in this case, the CRT 15 is in a state in which the normal posture is rotated by 90 degrees, so the sweep in the Y direction is performed with a period T, and the sweep in the X direction is performed with the scanning line in the Y direction. It is designed to be carried out at intervals of T, where the number of lines is n.

On the other hand, as shown in FIG. generates a firing pressure pulse for a certain period of time, which is applied to the transducer 7 as a reversible electro-mechanical transducer through the switch 6, so that the ultrasonic wave is emitted from the transducer 7 toward the living tissue 16 for a certain period of time. If the switch 6 is switched at the same time as the application of the high voltage pulse ends, the reflected ultrasound from the living tissue 16 will be transmitted to the transducer 7,
Since it is input to the CRT 15 as a brightness modulation signal via the switch 6, amplifier 8, detection circuit 9, and video signal synthesis circuit 10, the B mode is displayed on the CR7 display screen, that is,
The ultrasonic tomographic image is displayed from the set display start depth. In this case, it goes without saying that the vibrator 7 scans the biological tissue 16 by an appropriate method, such as linear scan or sector scan. Furthermore, it is clear that the time Tv in FIG. 2(e) corresponds to the display depth range.

As described above, the display start depth can be arbitrarily set by appropriately adjusting the variable resistor 1d, and this display start depth is also displayed as a numerical value in a specific display area of the CRT 15.

If numerical data is provided as a luminance modulation signal to the CRT 15 via the video signal synthesis circuit 10 within a specific period of the X direction sweep period and also within a specific period of the Y direction sweep period, the specific display area will be displayed. The setting display start depth can be displayed as a numerical value.

Of course, the displayed value in this case is the difference in pulse width T MWT3,
This corresponds to 1. The display numerical value is generated by measuring the difference in pulse width using a clock pulse having a period corresponding to the unit depth. In this example, as shown in the figure, the signal output from the XY sweep circuit 11 prior to the X direction sweep is used as a reset signal (+?) to reset the counter 14, while the first Y direction synchronization signal from the xY sweep circuit 11 is Clock pulses from the synchronizing signal generating circuit 4 are counted by a counter 14 via an AND gate 13 under gate control based on a signal outputted for a certain period of time Ts and a pulse width difference signal obtained from an inverter 3. . If the period of the clock pulse is made to correspond to the unit depth, the count value of the counter 14 will indicate the depth at which the setting display starts. Therefore, under the control of the XY sweep circuit 11, if numerical data is generated from the count value in the display numerical data generation circuit and sent to the CRT 15 via the video signal synthesis circuit 10, the set display start depth is set in the specific display area. It can be displayed.

As a result of the above, the image display mode is as follows.

That is, if the X sweep on the display screen is performed from left to right, and the Y sweep is performed from top to bottom, and the image is displayed on the entire display screen, then if T□=Ts, then A cross-sectional image of the biological tissue 16 within a certain distance from the surface of the transducer 7 as the display start depth is displayed on the display screen with the transducer surface, that is, the body surface of the subject, aligned with the top edge of the display screen. Become. However, in the case of T - TSW, the display start depth is shifted in the 16 direction of the living tissue by the distance corresponding to the difference,
That is, by aligning a certain depth portion from the transducer surface into the subject according to the difference between T and T,8 with the top edge of the display screen,
A cross-sectional image of the living tissue 16 within a certain distance from this point is displayed on the display screen. No matter how the display start depth is set, the image display starts at the top of the display screen, so by setting the display start depth large, the cross section at the deepest part of the biological tissue 16 can also be displayed. It's something you get. In the above embodiment, the χ direction sweep is also delayed by the Y direction sweep delay time, but this is because if this relationship is not maintained, the image as a whole will shift to the right. However, even if the entire X-direction sweep is not delayed, the entire image will actually shift to the right in the X-direction sweep by the Y-direction sweep delay time, and the shift caused by this is extremely small. In practice, this is hardly a problem.

Although the present invention is as described above, there are various other possible display start depth setting means. An example is a digital switch. While displaying the setting display start depth based on the value set by the digital switch, it is sufficient to start the Y direction sweep when the count value of the counter that counts clock pulses matches the above value. .

〔Effect of the invention〕

As explained above, the present invention variably controls the display start point in the depth direction of an ultrasound image by the display start depth setting means so that it matches the end of the CRT display screen corresponding to the depth direction of the subject. By displaying the display start depth as a numerical value on the display screen,
It is now possible to see areas that could not be seen with conventional display methods, display the diagnostic area in the center of the screen, and also display the starting point at what depth within the subject. You can see at a glance from where the depth of the displayed area is being displayed, and even if you take a photo and look at it later, you can immediately see from where the depth of the displayed area is displayed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of an example of an ultrasonic diagnostic apparatus according to the present invention, and FIG. 2 is an input/output signal waveform diagram in the configuration of FIG. 1. DESCRIPTION OF SYMBOLS 1... Monostable multi-bi break, 4... Synchronization signal generation circuit, 10... Video signal synthesis circuit, 11...
XY sweep circuit, 12...display numerical data generation circuit, 1
4...Counter, 15...CRT. Patent applicant Hitachi Medeico Co., Ltd. Agent Patent attorney Masami Akiki (1 other person) Figure 1 Figure 2

Claims (1)

[Claims] 1. Transmit ultrasound from an ultrasound transducer into the subject, receive the reflected echo signal by the transducer, and display the received signal as a brightness modulation signal on a predetermined area of the display means as an ultrasound image. In the ultrasonic diagnostic apparatus, a display start depth setting means for displaying an ultrasound image from a certain depth on the display means as a variable depth aligned with one end corresponding to the depth direction of the subject in the display area of the display means; ,
An ultrasonic diagnostic apparatus comprising: display start depth display means for displaying a display start depth of the ultrasound image on the display means together with the ultrasound image.