JP2553099B2 - Ultrasonic diagnostic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an apparatus for performing diagnosis using ultrasonic waves, and in particular, an ultrasonic pulse is repeatedly sent from a probe to a subject at a constant cycle, An ultrasonic observation device configured to process a reflected signal to display an ultrasonic tomographic image, and an oscillation frequency corresponding to the natural frequency of the probe, which is selectively connected as an adapter to the ultrasonic observation device. Has an oscillator,
The present invention relates to an ultrasonic diagnostic apparatus including a blood flow analysis unit that detects the Doppler shift of a reflection signal from a subject by the output signal of this oscillator and analyzes the average blood flow velocity, flow velocity distribution, and the like.

[Conventional technology]

An ultrasonic diagnostic apparatus is known that displays a tomographic image by ultrasonic waves and performs blood flow analysis as described above. In this case, it has been proposed that a plurality of probes each having a different natural frequency can be selectively used so that the best blood flow analysis can be performed according to the site to be diagnosed of the subject. In such an ultrasonic diagnostic apparatus, a plurality of oscillators corresponding to the natural frequencies of the respective probes are provided, and one of them is selected according to the probe used to detect the Doppler shift. I am trying. In this case, since the ultrasonic observation unit that displays an ultrasonic tomographic image and the blood flow analysis unit that detects the Doppler shift and performs the blood flow analysis are integrated, the ultrasonic waves supplied to the probe The transmission pulse and the output signal of the oscillator for Doppler shift extraction for blood flow analysis are always synchronized, and it is not necessary to provide a special synchronization means.

On the other hand, there is also proposed an ultrasonic diagnostic apparatus in which a blood flow analysis unit is selectively connected as an adapter to an ultrasonic observation apparatus for displaying an ultrasonic tomographic image so that the function can be expanded. Generally, as a blood flow analysis unit using ultrasonic waves, a continuous Doppler method, a pulse Doppler method, and a two-dimensional blood flow display method have been proposed. Among them, the one adopting the pulse Doppler method is an ultrasonic observation apparatus. It is suitable for the combination of.

[Problems to be solved by the invention]

In the conventional ultrasonic diagnostic apparatus in which the above-mentioned pulse Doppler type blood flow analysis unit is selectively connected to the ultrasonic observation apparatus as an adapter, the ultrasonic waves sent to the body are received by the Doppler Since there is only one oscillator for extracting the shift amount,
When a probe with a different natural frequency was used depending on the diagnosis site, there was a drawback that the efficiency was poor and a sufficient S / N could not be obtained and an accurate blood flow analysis could not be performed. In order to eliminate such a defect, a plurality of blood flow analysis units each having a local oscillator corresponding to the natural frequency of the probe are prepared, and the ultrasonic observation apparatus is selectively selected according to the probe used. Although a system for connecting to the device is conceivable, it requires a plurality of blood flow analysis units, which increases the equipment cost, and the operation for selecting and connecting is troublesome, and there is a possibility that a connection error may occur.

An object of the present invention is to eliminate the above-mentioned conventional drawbacks and to detect the Doppler shift in an optimum state for a plurality of probes each having a different natural frequency using one blood flow analysis unit, Moreover, it is an object of the present invention to provide an ultrasonic diagnostic apparatus which has good operability and is free from operational mistakes.

[Means and Actions for Solving Problems]

The present invention relates to an ultrasonic observation apparatus for repeatedly transmitting ultrasonic pulses from a probe to a subject in response to an ultrasonic transmission pulse and visualizing a reflected signal from the subject, and the ultrasonic observation device. A blood flow that is selectively connected to the device and has an oscillator having an oscillation frequency corresponding to the natural frequency of the probe, and the Doppler shift of the reflected signal is detected by the output signal of the oscillator to analyze the blood flow. In an ultrasonic diagnostic apparatus including an analysis unit, the blood flow analysis unit includes a plurality of oscillators respectively corresponding to a plurality of probes having different natural frequencies, and a probe using these oscillators. It is characterized in that it is provided with an oscillator selecting means that automatically selects the ultrasonic wave in response to the selection, and a synchronizing means that synchronizes the ultrasonic transmission pulse supplied to the probe with the output signal of the selected oscillator.

According to the ultrasonic diagnostic apparatus of the present invention described above, since the oscillator corresponding to the natural frequency of the probe to be used is automatically selected, operability is good, no operation error occurs, and Doppler shift is extracted. Since the optimum oscillator is always selected in order to achieve high efficiency, sufficient S / N can be obtained. Furthermore, since the ultrasonic transmission pulse supplied to the probe is synchronized with the output signal of the oscillator, the Doppler shift can be accurately detected. As described above, according to the ultrasonic diagnostic apparatus of the present invention, the optimum probe can be used according to the diagnosis site, and thus the best diagnosis can be performed.

〔Example〕

FIG. 1 is a block diagram showing the configuration of an embodiment of the ultrasonic diagnostic apparatus according to the present invention. The ultrasonic diagnostic apparatus of the present invention includes an ultrasonic observation apparatus 1 that displays an ultrasonic tomographic image, and a blood flow analysis unit 21 that is selectively connected to the ultrasonic observation apparatus as an adapter. The ultrasonic observation apparatus 1 can be used by itself, and includes an oscillator 2 that generates a signal having an ultrasonic pulse repetition frequency when the blood flow analysis unit 21 is not connected. The output signal of the oscillator 2 is supplied to the frequency divider 4 via the switching circuit 3. A conductor 7 connected to a positive voltage source + V via a resistor 6 is connected to the control terminal 5 of the switching circuit 3. When the blood flow analysis unit 21 is not connected, the conductor 7 is pulled up to a positive voltage, and the switching circuit 3 supplies the output signal of the oscillator 2 to the frequency divider 4 as shown by the broken line. Driven. The signal frequency-divided by the frequency divider 4 is further supplied to the control circuit 8 to generate an ultrasonic wave transmission pulse, which is supplied from the connector 9 to the probe 10. The ultrasonic waves emitted from the probe 10 to the subject are reflected by the subject, received by the probe, and converted into echo signals.
This echo signal is supplied to the control circuit 8 via the connector 9, converted into an image signal, and displayed on the display device 11, for example,
It is displayed as an ultrasonic tomographic image in B mode. The ultrasonic observation apparatus 1 further has terminals 1a to 1g for connecting the blood flow analysis unit 21, the terminal 1a is connected to the connector 9, and a frequency code signal representing the type of the probe 10 is supplied to the blood flow. It supplies to the analysis unit 21, the terminal 1b is connected to the switching circuit 3, the terminal 1c is connected to the output terminal of the frequency divider 4, and the terminals 1e, 1f, 1g are connected to the control circuit 8. Has been done.

The blood flow analysis unit 21 includes a plurality of oscillators 22a, 22b, 22c each having an oscillation frequency corresponding to the natural frequency of the probe used, and a frequency selector 23 for selecting one of the outputs of these oscillators. And a Doppler control circuit 24 and a synchronization circuit 25 that receive this output. Oscillators 22a-2
The oscillation frequency of 2c can be 3.5, 5.0 and 7.5 MHz, for example. Further, the blood flow analysis unit 21 has terminals 21 connected to the terminals 1a to 1g of the ultrasonic observation apparatus 1, respectively.
a to 21g are provided, the terminal 21a is connected to the control terminal of the frequency selector 23, the terminal 21b is connected to the output terminal of the frequency selector,
Terminals 21c and 21d are respectively connected to the input terminal and the output terminal of the synchronous circuit 25, and the terminal 21e is grounded via the conductor 26,
The terminals 21f and 21g are connected to the input terminal and the output terminal of the Doppler control circuit 24, respectively.

Next, the operation of the apparatus of this example will be described. First, the case where only the ultrasonic observation apparatus 1 is used without connecting the Doppler blood flow analysis unit 21 will be described.

When the blood flow analysis unit 21 is connected, the lead wire 7
The potential of is pulled up to a positive voltage, and the switching circuit 3 is switched so as to supply the output signal of the oscillator 2 to the frequency divider 4. At the same time, the positive potential of the lead wire 7 is also applied to the control circuit 8, so that the control circuit detects that the blood flow analysis unit 21 is not connected. The signal frequency-divided by the frequency divider 4 is supplied to the control circuit 8, and an ultrasonic transmission pulse having a predetermined repetition frequency synchronized with the output signal of the oscillator 2 is applied to the probe 10 via the connector 9. As a result, the probe 10 radiates ultrasonic waves having the natural frequency to the subject. The ultrasonic waves reflected by the subject are received by the probe 10 and converted into echo signals. This echo signal is supplied to the control circuit 8 via the connector 9. The control circuit 8 having a scan converter processes the echo signal to create an image signal, and displays an ultrasonic tomographic image on the display device 11. As described above, since the control circuit 8 detects that the blood flow analysis unit 21 is not connected, the data regarding blood flow is not displayed.

Next, the operation when the blood flow analysis unit 21 is connected to the ultrasonic observation apparatus 1 will be described. In this case, since the conductor 7 is grounded via the terminals 1e and 21e and the conductor 26,
The potential of the lead wire 7 becomes zero, the switching circuit 3 is switched to the position opposite to the position shown by the broken line in FIG. 1, and the control circuit 8 detects that the blood flow analysis unit 21 is connected. Further, since the terminals 1a and 21a are connected, the frequency code representing the natural frequency of the probe 10 is the connector 9
And the terminals 1a and 21a are supplied to the control input terminal of the frequency selector 23, and the frequency selection circuit outputs the output signal of the oscillator 22a, 22b or 22c designated by the frequency code to the conductor 27. This oscillator output signal is
It is supplied to the switching circuit 3 via 21b and 1b, and is further supplied to the frequency divider 4 through this. When detecting that the blood flow analysis unit 21 is connected, the control circuit 8 is prohibited from inputting the output signal of the frequency divider 4 and receives the signal supplied from the terminal 1d. Has become. Therefore, the output signal of the frequency divider 4 is supplied to the synchronizing circuit 25 via the terminals 1c and 21c.

FIG. 2 shows an example of the structure of the synchronizing circuit 25.
This example comprises a D flip-flop 25a, the data input terminal 25b of which is supplied with the output signal from the frequency divider 4 as shown in FIG. 3A, and the clock input terminal 25c of which frequency is shown in FIG. 3B. The output signal from the selector 23 is supplied. Although the phases of these signals are not synchronized with each other due to the phase delay in the frequency divider 4, the frequency output of the frequency selector 2 from the Q output terminal 25d of the D flip-flop 25 as shown in FIG. 3C.
A signal perfectly synchronized with the output signal from 3 will be obtained. This signal is sent to the control circuit 8 via terminals 21d and 1d.
Is supplied to. The control circuit 8 generates an ultrasonic transmission pulse in synchronism with this signal, which is transmitted through the connector 9 to the probe 10
To generate an ultrasonic pulse at a predetermined repetition period. The vibration frequency of this ultrasonic pulse is determined by the natural frequency of the probe 10, but in this example it is approximately 3.5,5.0
And those that generate 7.5 MHz ultrasonic pulse are selectively used according to the site to be diagnosed. The ultrasonic waves reflected from the subject are converted into echo signals by the probe 10 and supplied to the control circuit 8. The control circuit 8 performs the same processing as described above to display an ultrasonic tomographic image on the display device 11. At the same time, the control circuit 8 outputs the echo signal to the terminal 1f.
And 21f to supply to the Doppler control circuit 24. In the Doppler control circuit 24, the echo signal is subjected to synchronous detection by a signal supplied from the frequency selector 23 to extract the Doppler shift, and further frequency analysis is performed to analyze the blood flow such as the average blood flow velocity and blood flow distribution. Form analytical data. The blood flow analysis data is supplied to the control circuit 8 via the terminals 21g and 1g and displayed on the display device 11 together with the ultrasonic tomographic image. As described above, in the present invention, the frequency code is supplied to the frequency selector 23 by connecting the probe 10 to the connector, and the frequency selector outputs the desired oscillator 22a, 22b or 22c according to the frequency code. Since the signal is automatically selected, the operability is very good and the possibility of operation error is greatly reduced. In addition, the signal output from the frequency selector 23 is frequency-divided by the frequency divider 4,
Since the synchronizing circuit 25 is again synchronized with the output signal of the frequency selector, the Doppler control circuit 24 can properly detect the Doppler shift, and accurate blood flow analysis data can be obtained.

〔The invention's effect〕

According to the ultrasonic diagnostic apparatus of the present invention, when a blood flow analysis unit is connected, a plurality of probes each having a different natural frequency can be selectively used according to the site to be diagnosed. Optimal blood flow analysis can be performed according to Furthermore, in this case, the optimum one is automatically selected from the plurality of oscillators provided in the blood flow analysis unit, which simplifies the operation and eliminates the possibility of operation mistakes, thus greatly improving the operability. become.

Further, since the output signal of the oscillator automatically selected in this way and the ultrasonic transmission pulse are synchronized,
The Doppler shift can be accurately extracted.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the ultrasonic diagnostic apparatus according to the present invention, FIG. 2 is a circuit diagram showing the configuration of its synchronizing circuit, and FIGS. 3A, 3B and 3C are the same. It is a signal waveform diagram for explaining. 1 ... Ultrasonic observation device, 2 ... Oscillator 3 ... Switching circuit, 4 ... Divider 8 ... Control circuit, 10 ... Probe 11 ... Display device, 21 ... Blood flow analysis unit 22a , 22b, 22c …… Oscillator 23 …… Frequency selector, 24 …… Doppler control circuit 25 …… Synchronous circuit

Claims (1)

(57) [Claims] 1. An ultrasonic observing device for repeatedly transmitting ultrasonic pulses from a probe to a subject in response to an ultrasonic transmission pulse at a constant cycle to visualize a reflected signal from the subject, and an ultrasonic observation device. A blood analyzer that is selectively connected to the observation device and has an oscillator having an oscillation frequency corresponding to the natural frequency of the probe, detects the Doppler shift of the reflected signal by the output signal of this oscillator, and analyzes the blood flow. In an ultrasonic diagnostic apparatus including a flow analysis unit, the blood flow analysis unit includes a plurality of oscillators respectively corresponding to a plurality of probes having different natural frequencies, and a probe using these oscillators. Ultrasonic diagnostics characterized by including an oscillator selecting unit that automatically selects the ultrasonic transmitting pulse supplied to the probe and a synchronizing unit that synchronizes the ultrasonic transmission pulse supplied to the probe with the output signal of the selected oscillator. Location.