JPS6129735B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic diagnostic apparatus that can perform both M-mode measurement and Doppler effect flow rate measurement on a specimen.

In recent years, ultrasonic diagnostic equipment that injects ultrasound into a specimen such as the human body and measures and displays specimen information from the reflected, transmitted, or scattered waves has become more non-invasive and less dangerous than X-ray imaging equipment. It has rapidly become popular due to these features.

There have been various kinds of ultrasonic diagnostic equipment depending on the measurement and display method, but one of them is to fix a probe in acoustic contact with the specimen, and emit ultrasonic waves from this to detect the inside of the specimen. The waves are reflected from the boundaries of each medium with different acoustic impedances, and the reflected waves are received by a probe and converted into electrical signals.The reflected waves are then brightly modulated at the electrical signal level to display the reflection position on a display. By repeating the operation of emitting ultrasonic waves again at regular intervals and displaying the reflected position on a different scanning line at regular intervals, the temporal change in the reflected position within the specimen is displayed.
Mode's ultrasonic diagnostic equipment was installed. According to this M-mode ultrasonic diagnostic apparatus, it is possible to observe the movement of heart valves, etc., and for example, a display as shown in FIG. 1 is displayed on the display.

In addition, conventional ultrasound diagnostic equipment irradiates ultrasonic waves onto a moving medium within a specimen, and measures the frequency shift caused by the Doppler effect between the irradiated ultrasound waves and the reflected ultrasound waves. There were also some that measured the movement of the medium. An ultrasonic diagnostic apparatus that utilizes the Doppler effect can be used to measure blood flow velocity when the specimen is a living body.

However, conventional ultrasonic diagnostic equipment that uses the M mode or the Doppler effect described above can only measure the specimen from one direction, and the M mode and the Doppler effect that use the The positions that can be measured and displayed were different (for example, when the specimen is a human body, the probe position of the M-mode ultrasonic diagnostic device is best between the 2nd and 4th ribs, and the position that uses the Doppler effect is Therefore, it was normal to use both independently.

However, the combined use of the above-mentioned M-mode ultrasound diagnostic device and ultrasound diagnostic device that utilizes the Doppler effect makes the specimen information more useful and accurate than when used alone. ,
It has been more coveted than before.

An object of the present invention is to provide an ultrasonic diagnostic apparatus that satisfies the above requirements by having separate probes for M mode and probes for measuring specimen information using the Doppler effect.

The present invention includes a first probe that emits ultrasonic waves into a specimen, receives the reflected waves, and converts them into electrical signals, and a moving medium inside the specimen that has a different quality than the first ultrasound. a second probe that irradiates ultrasonic waves selected from the above and receives the reflected waves and converts them into electrical signals; a control section that performs M-mode measurement from the received signal of one or both of the probes; a speed detection section that measures the speed of the moving medium by extracting signal fluctuations due to the Doppler effect from the received signal of one or both of the probes; The device is equipped with an output section that visually outputs information, and is configured to obtain an M-mode reception signal and a speed measurement reception signal using the first and second probes, and an example thereof will be explained below. do.

FIG. 2 shows a block system diagram of an embodiment of the apparatus of the present invention. In the figure, 1 is the specimen, and the first probe 2
a, the second probes 2b are in acoustic contact with each other. Here, the probes 2a and 2b are configured to be movable on the same plane, and their ultrasonic waves are applied to, for example, a blood vessel 3 within the specimen 1. Probe 2
The angle θ at which the ultrasonic waves A and B from a and 2b intersect in the blood vessel 3 is detected by an angle detector 4 such as a potentiometer, and the intersection point of both ultrasonic waves A and B is detected by an intersection calculation unit. 5 through arithmetic processing. This calculation is performed using known geometric formulas.

Further, the probes 2a and 2b emit ultrasonic waves at predetermined timings based on output signals from the signal transmitting and receiving circuit sections 7a and 7b whose operation is controlled by signals from the transmitting and receiving timing control section 61 in the control section 6, and the ultrasonic waves are reflected. Receives waves and performs acoustic-to-electrical conversion. The signal transmitting/receiving circuit sections 7a and 7b both have the same configuration, and include a transmitting amplifier 71, a receiving amplifier 72, a filter 73, and the like. However, probes 2a and 2b
The ultrasonic waves A and B emitted from each other are characterized by different qualities (frequency, waveform, pulse train, etc.). Circuit section 7
The characteristics of the filters 73 in a and 7b are different from each other.

First, the probes 2a, 2b are driven by the output signals of the transmitting amplifiers in the signal transmitting/receiving circuits 7a, 7b, and from this, ultrasonic waves A and B of different quality are emitted in three directions of blood vessels in the specimen 1. . Here, the second
As shown in the figure, the ultrasonic waves A are emitted in a direction substantially perpendicular to the blood vessel 3, while the ultrasonic waves B are emitted in a direction substantially parallel to the direction in which blood flows within the blood vessel 3. This is for the purpose of displaying the M mode using ultrasonic waves A and measuring blood flow velocity using ultrasonic waves B, which will be described later, at optimal positions.

The reflected waves of the ultrasonic waves A and B are received by the probes 2a and 2b, where they are subjected to acoustic-to-electrical conversion, and then applied to the filter via the receiving amplifiers in the signal transmitting and receiving circuits 7a and 7b. Only the received signal of the reflected wave to be received is separated and extracted. For example, when ultrasonic waves A and B of different frequencies are used, the filter in the signal transmitting/receiving circuit section 7a
A filter 73 in the signal transmitting/receiving circuit section 7b passes only the frequency of the ultrasonic wave B (for example, 1MHz).
A bandpass filter is used that only passes the signal. In addition, if different waveforms (wave width, shape) are used as ultrasonic waves A and B, the signal transmitting/receiving circuit section 7
The filters in a and 7b are filters that discriminate between the wave widths or shapes of the ultrasonic waves A and B.
Furthermore, when ultrasonic waves having pulse trains of different periods are used as the ultrasonic waves A and B, a filter that discriminates the difference in the period of the pulse trains is used as the above-mentioned filter.

In this way, only the received signal of the reflected wave of the ultrasonic wave A is separated and extracted from the signal transmitting/receiving circuit section 7a.
On the other hand, only the received signal of the reflected wave of the ultrasonic wave B is separated and extracted from the signal transmitting/receiving circuit section 7b. The output reception signal of the signal transmission/reception circuit section 7a is applied to the Doppler blood flow detection section 8a and the contact point RO of the changeover switch _SW3 . On the other hand, the output reception signal of the signal transmission/reception circuit section 7b is supplied to the Doppler blood flow detection section 8b.

The Doppler detection units 8a and 8b are known detection units that determine the flow velocity of blood in the blood vessel 3 from the frequency shift caused by the Doppler effect. Here, since the received signal supplied to the Doppler blood flow detection unit 8b is obtained from the reflected wave of the ultrasound wave B that is substantially parallel to the blood flow direction, the Doppler effect can be optimally applied. The detection unit 8b can obtain accurate blood flow measurement results. On the other hand, since the received signal supplied to the Doppler detection unit 8a is obtained from the reflected wave of the ultrasonic wave A, the Doppler effect cannot be expected much, and the Doppler blood flow detection unit 8a performs blood flow measurement with low accuracy. Get results.

The Doppler blood flow detection units 8a and 8b detect the blood flow velocity at the intersection position of the ultrasonic waves A and B using the output signal of the sampling position setting unit 9 to which the output signal of the intersection calculation unit 5 is supplied. It can be done. Of course, the sampling position setting section 9 can set the blood velocity detection position at any position on the propagation path of the ultrasonic waves A and B.

The output signals of the Doppler detection sections 8a and 8b are supplied together with the output signal of the intersection point calculation section 5 to a vector calculation section 10, where a blood flow velocity vector is calculated. That is, as shown in FIG. 3, when the Doppler detection result by ultrasound A is a and the Doppler detection result by ultrasound B is b, the magnitude and angle of this vector of blood flow velocity are as shown in FIG.
Letting the intersection angle be θ, it is expressed by X and α in the following equation.

The calculation result of the vector calculation section 10 is supplied to the contact point RO of the changeover switch _SW1 . changeover switch
The SW ₁ has contacts A and B, and the output signal of the Doppler blood flow detection section 8b is supplied to the contact A. _SW2 is also a changeover switch, contact A is an empty contact, and contact B is supplied with a signal taken out from the movable contact piece of changeover switch _SW3 .

Now, to explain the case where the M mode display and the blood flow velocity are displayed, in this case, the changeover switch SW 1 is set to contact A, and the changeover switch SW ₁ is set to contact A.
SW ₂ and SW ₃ are each connected to contact RO. As a result, the received signal taken out from the signal transmitting/receiving circuit section 7a is supplied to the display/recording section 11 via the changeover switches SW ₃ and SW ₂ , where the blood vessel 3 is displayed in M mode, and the blood vessel 3 is displayed in the M mode. The state of expansion and contraction is displayed. Meanwhile, at the same time, the Doppler detection section 8
The output signal taken from b is the changeover switch SW ₁
The output signal and the output signal from the sampling position setting section 9 are then supplied to the display/recording section 11, where the measurement results of the blood flow velocity using the ultrasonic waves of the probe 2b of the blood vessel 3 are displayed.

In this case, when further displaying blood flow velocity measurement points on the M mode display, the scanning line of the M mode display in the display recording section 11 and the scanning line of the display of the received signal for flow velocity measurement obtained from the probe 2b are The intersection points of both scanning lines can be set in advance so that they intersect obliquely or at right angles, respectively, and the intersection point of both scanning lines can be displayed on the display screen in M mode, and this can be used as the blood flow velocity measurement point. Therefore, in this case, during the M mode display shown in FIG. 4, the blood flow velocity shown by and the velocity measurement point shown by can be displayed. Further, at this time, control may be performed so that the intersection of both scanning lines automatically becomes the blood flow velocity measurement point.

Next, we will explain the operation when simultaneously displaying the M mode using ultrasound from the probe 2a and displaying the blood velocity vector at the same point as the M mode measurement point. Changeover switch SW ₁ ,
Both SW ₂ and SW ₃ are connected to the contact low side. As a result, the display recording section 11 has the signal transmitting/receiving circuit 7a.
At the same time that the output reception signal is supplied, the output signal of the vector calculation section 10 is supplied, and the blood flow velocity vector at the measurement point in the M mode is displayed. This case has the advantage that the measurement result of the blood flow velocity in the blood vessel 3 becomes more accurate.

Next, each embodiment of the display method in the display recording section 11 will be described. First, the first display method is to display the magnitude and angle of the blood flow velocity or blood flow velocity vector in a direction perpendicular to the display time axis, with the display point of the blood flow velocity measurement point on the display scanning line of M mode as the base point. Display above. In this case, the blood flow velocity is displayed as shown in FIG. 4, the magnitude of the blood flow velocity vector is shown in FIG. 5, and its angle is displayed as shown in the same figure. Here, FIGS. 4 and 5
In the figure, indicates the M mode display, and indicates the speed measurement point display.

The second display method is a method in which the M mode, blood flow velocity, blood flow velocity vector size, and angle are all displayed in different colors. Furthermore, the third
As shown in Fig. 6, the display method is to display an arrow whose magnitude of the blood flow velocity vector is proportional to its length and whose angle is proportional to its direction, with the blood velocity velocity display measurement point as the base point. method (arrows may be line segments or other shapes). In this case, it is easy to understand intuitively if the direction of the M mode scanning line is used as a reference. Of course, vector display arrows, line segments, and other figures can also be displayed in M mode and in different colors. Further, the above-mentioned arrows, line segments, and other figures displayed as vectors may be recorded at specific time intervals. This is to prevent continuous display from overlapping the previous display portion and making it unsightly.

The above display and recording by the display recording section 11 is performed by an output control signal from the display control section 62 that is synchronized with the transmission/reception timing within the control section 6 in FIG.
In addition, when changeover switch SW ₂ is connected to contact point RO, when changeover switch SW ₁ is connected to contact point A, only the blood flow velocity in blood vessel 3 is displayed, and when SW ₁ is connected to contact point RO, the blood flow rate is displayed. It is clear from FIG. 2 that only the flow velocity vector is displayed.

In addition, the blood flow velocity in the blood vessel 3 is not uniform (it has a parabolic distribution in laminar flow), and it is necessary to find the average velocity, but it is not possible to find the average velocity from the velocity vector X etc. obtained by the Doppler effect. Since it is generally known, the explanation is omitted.

As described above, according to the present invention, the M-mode measurement is performed from the signal received by the first probe, and the velocity of the moving medium is measured by the Doppler effect from the signal received by the second probe. Therefore, the first and second probes can be assigned to the most suitable position for M mode measurement and display, and the most suitable position for speed measurement and display, and also for M mode in the display recording section. Since the display scanning line and the display scanning line of the received signal for flow rate measurement are set in advance to be oblique or perpendicular to each other, and the intersection of both scanning lines is displayed, the flow rate measurement point is displayed on the M mode display. Furthermore, since the flow velocity is measured and displayed by vector calculation of each of the signals received from the first and second probes, only the signals received from the second probe are used. It is possible to obtain more accurate flow velocity information than in the case of
When a figure whose direction changes proportionally is displayed, it is possible to intuitively understand the magnitude and direction of the flow velocity, which is more useful and accurate than displaying the M mode and the flow velocity separately. It has features such as rapid diagnosis.

[Brief explanation of the drawing]

Figure 1 shows an example of the display in M mode, Figure 2 shows an example of the display in M mode.
The figure is a block system diagram showing one embodiment of the device of the present invention, FIG. 3 is a diagram explaining the calculation method of the vector calculation section in FIG. 2, and FIGS. It is a figure showing each display mode in a device. 1... Specimen, 2a, 2b... Probe, 3... Blood vessel, 4... Angle detector, 6... Control unit, 7a, 7
b...Signal transmission/reception circuit, 8a, 8b...Doppler blood flow detection section, 9...Sampling position setting section, 1
0...Vector calculation unit, 11...Display recording unit.

Claims (1)

[Claims] 1. A first probe that emits ultrasonic waves into a specimen and receives the reflected waves and converts them into electrical signals;
A second probe that irradiates a moving medium within the specimen with an ultrasonic wave selected to have a quality different from that of the reflected wave from the first probe, and receives the reflected wave and converts it into an electrical signal. a control unit that drives each of the first and second probes and performs M-mode measurement from a received signal of the one probe; and a received signal of one or both of the probes; The first and second probes are equipped with a velocity detection section that extracts signal fluctuations due to the Doppler effect from the moving medium and measures the velocity of the moving medium, and an output section that visually outputs the measurement information.
An ultrasonic diagnostic apparatus characterized by obtaining a mode reception signal and a speed measurement display reception signal. 2. The output section performs each display so that the M mode display scanning line and the output signal display scanning line of the speed detection section are obliquely or orthogonally crossed, respectively, and both scanning lines of the output section 2. The ultrasonic diagnostic apparatus according to claim 1, wherein the intersection point is displayed as the velocity measurement point of the area in the specimen measured in M mode. 3. The speed detection unit is a detection and calculation unit that calculates a vector of the velocity from the results obtained by measuring the velocity of the moving medium separately using the Doppler effect from the received signals of the first and second probes. and the output unit is configured to display the M-mode display and the velocity measurement result, and the M-mode display and the velocity vector of the moving medium are simultaneously displayed, respectively. The ultrasonic diagnostic apparatus according to item 1. 4 The visible light output section outputs the M mode measurement information and the M mode measurement information.
Measurement information regarding speed other than mode measurement information and at least one of color difference or position difference.
An ultrasonic diagnostic apparatus according to any one of claims 1 to 3, characterized in that the ultrasonic diagnostic apparatus outputs images by distinguishing between the two. 5. The visible light output section is configured to display the measured vector information using either a pattern indicating the rotation angle and the magnitude of the vector, or a display pattern having a direction and magnitude corresponding to the vector information. An ultrasonic diagnostic apparatus according to any one of claims 1 to 4.