JPH0277241A - Ultrasonic doppler diagnosing device - Google Patents

Abstract

PURPOSE:To execute the action checks and evaluations of a Doppler system and a CFM without using a blood flow phantom by providing a variable delay circuit for changing the delay quantity of a probe signal to the transmitting or receiving circuit of a probe. CONSTITUTION:Echo signals from probes 5a, 5b,... 5n are amplified by preamplifiers 6a, 6b,... 6n, thereafter, they are inputted to a delay adding circuit 15, a delay addition for a steering and a reception focusing is executed, and the signals are bound into one bipolar signal. A phase offset control part 21 instructs the delay quantity of a phase offset part 20 in making a system trigger 16 into a clock, the phase offset part 20 gives a proper delay to the bipolar echo signal from the delay adding circuit 15 based on a control signal from the phase offset control part 21, and the result is outputted to a Doppler processing part after a mixer. At the time of checking the Doppler system and CFM, a phase offset is controlled by a prescribed time chart.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to improvements in ultrasonic Doppler diagnostic equipment.

[Prior Art] Recently, in the medical field, ultrasound has been widely used not only for diagnosis but also for treatment, heating, destruction, and cleaning. In particular, ultrasonic Doppler diagnostic equipment that uses the Doppler effect,
It is used to measure the speed of blood flow in blood vessels, and has great clinical effects.

Fig. 4 is a block diagram of this ultrasonic Doppler diagnostic device, and Fig. 5 is a detailed diagram of its main parts, where 1 is a controller, 2 is a transmission waveform generation circuit, 3 is a driver, 4 is a transmission power source, and 5 is a detailed diagram of the main parts. Probe, 6
is a preamplifier, 7 is a mixer, 8 is a local oscillator, 9 is a low-pass filter, 10 is a range gate, 11 is a Boxcar integrator, 12 is a sample and hold circuit, 13 is a bandpass FFT analysis section, 14 is a transmission delay control circuit , 15 is a delay adder circuit, and 16 is a system trigger.

In the figure, a signal output from a transmission waveform generating circuit 2 is boosted by a driver 3 and sent to a probe 5, where the probe 5 converts it into an ultrasonic wave and transmits it to a target site in the body. The transmitted ultrasonic waves are reflected at various parts of the body and return as echoes, so the echoes are converted into electrical signals by the probe 5, amplified by the preamplifier 6, and output to the mixer 7. The echo signal is mixed in the mixer 7 with a signal having a local oscillation frequency output from the local oscillator 8 to obtain an intermediate frequency of the Doppler frequency, which is output as a Doppler signal via the sample and hold circuit 12.

Note that the driver 3, the probe 5, and the preamplifier 6 are composed of a large number of pieces as shown in FIG. The beam is steered and focused.

[Problems to be Solved by the Invention] By the way, in the above-mentioned conventional ultrasonic Doppler diagnostic device, the Doppler system and CFM (Color F
To check the operation of low Mapplng),
When performing a comprehensive examination including the acoustic system, a blood flow phantom for ultrasonic Doppler diagnostic equipment using simulated blood is required.

However, simulated blood is prone to precipitation and deterioration of solid content, and its stability is problematic, and it also requires equipment to drive the blood flow phantom. It is not possible to perform operation checks and evaluations, which has long been considered a problem.

The present invention was made to solve the above-mentioned problems of conventional devices, and it is possible to use normal B
Using a fixed reflector phantom for mode check,
The present invention aims to provide an ultrasonic Doppler diagnostic device that can check and evaluate the operation of a Doppler system including an acoustic system and CFM.

[Means for Solving the Problems] In order to achieve the above object, the ultrasonic Doppler diagnostic device according to the present invention includes a variable device in the transmitting or receiving circuit of the probe for changing the amount of delay of the probe signal. Equipped with a delay circuit.

[Operation] A pseudo Doppler shift is generated in the echo signal by applying a delay offset to the echo signal from the fixed reflector phantom input to the Doppler processing system using the delay circuit. As a result, this Doppler-shifted signal can be used to improve the Doppler system of diagnostic equipment and CF.
It becomes possible to check M.

[Embodiments of the invention]

Fig. 1 is a partial configuration diagram of a diagnostic device equipped with a variable delay circuit in the receiving system, which is an embodiment of the present invention, and Fig. 2 is a diagram showing changes in each signal when the variable delay circuit is activated. be. In the figure, 2 to 15 are the same or equivalent parts as the conventional device, 2
0 is a phase offset section, 21 is a phase offset control section,
A is a diagram showing the output of the Doppler system trigger, B is a phase offset control signal, and C is a diagram showing the delay amount of the echo signal.

As shown in the figure, a variable delay circuit including a phase offset section and a phase offset control section is provided after the delay addition circuit 15.

The probes 5as, 5bs, . . . , 5n are driven by drive signals suitably delayed for steering and focusing. probe 5as
After the echo signals from 5bs...5n are amplified by preamplifiers 6a, 6b,...6n, they are input to a delay adder circuit 15, where delay addition is performed for steering and reception focusing. It is combined into one bipolar signal.

The phase offset control section 21 uses the system trigger 16 as a clock to command the delay amount of the phase offset section 20, and the phase offset section 20 uses the system trigger 16 as a clock to command the delay amount of the phase offset section 20.
Based on the control signal from the delay adder circuit 1
It is configured to give an appropriate delay to the bipolar echo signal from 5 and output the result to the Doppler processing section after the mixer.

During normal scanning, the phase offset control unit 21 controls the phase offset unit 20 so that a constant delay is always maintained.
control.

Also, if you want to check the Dotsupura system or CFM,
The phase offset is controlled according to the time chart shown in FIG. That is, the delay amount of the echo signal is changed in the same cycle as the transmission using a Doppler system trigger, and the phase shift section is controlled so that this change is repeated in a certain cycle T. However, the maximum value Δt of the delay amount of the echo signal
The wax must be small enough that the echo signal of the fixed reflector phantom does not deviate from the handling time of the Doppler signal processing section.

By applying the above delay to the echo signal from the fixed reflector phantom, the echo signal is considered to be equivalent to the depth of the fixed reflector phantom changing with the period T1 maximum Δt laX, and the pseudo Doppler is It is considered to be occurring.

In this embodiment, the phase offset section 20 is arranged independently, but the delay adder circuit 15 may be provided with an equivalent function. That is, the same effect can be achieved even if the delay addition control is changed so that the delay amount shown in FIG. 2 is applied equally to the echo signals of all channels.

FIG. 3 is a block diagram showing another embodiment, in which delay and offset control is performed in the transmission system. That is, the transmission delay control circuit 14 includes a phase offset control section 22,
In the normal operation mode, the transmission delay control circuit 14 controls the phase of drive pulses for each channel for steering and focusing, and in the test mode, it applies a delay offset equally to all channels. Also in this embodiment, as in the above embodiment, it is possible to generate a pseudo Doppler shift in the echo signal from the fixed reflector phantom.

[Effects of the Invention] The present invention provides an ultrasonic Doppler diagnostic device that includes variable delay circuits in the receiving system from the probe and the transmitting system to the probe, and performs delay control of echo signals. It has become possible to check the operation of the Doppler system and CFM without using a blood flow phantom that lacks stability, and the efficiency of using the ultrasonic Doppler diagnostic device has been greatly improved.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the main parts of an ultrasonic Doppler diagnostic device showing an embodiment of the present invention, Fig. 2 is a diagram showing the relationship between the human input signal of the variable delay circuit and the system trigger, and Fig. 3 is a diagram showing the relationship between the human input signal of the variable delay circuit and the system trigger. FIG. 4 is a block diagram of the main parts of the ultrasonic Doppler diagnostic apparatus of the embodiment, FIG. 4 is a block diagram of the conventional ultrasonic Doppler diagnostic apparatus, and FIG. 5 is a block diagram of the main parts thereof. In the figure, 20 is the phase offset section, 21.22 is the phase offset control section, A is the output waveform of the Doppler system trigger, B is the output waveform of the phase offset control signal, and C is the waveform showing the delay amount of the echo signal. . Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Patent Attorney Muneharu Sasaki

Claims (2)

[Claims] (1) For the echo signal from the fixed reflector phantom,
An ultrasonic Doppler diagnostic device characterized by being configured to change a system state at the same cycle as a Doppler sampling cycle and generate a pseudo Doppler shift. (2) The means for generating the above-mentioned pseudo Doppler shift includes a variable delay circuit in the transmitting or receiving circuit of the probe of the ultrasonic Doppler diagnostic device, and generates the probe signal at the same period as the Doppler sampling period. 2. The ultrasonic Doppler diagnostic apparatus according to claim 1, wherein the ultrasonic Doppler diagnostic apparatus is configured to apply a delay offset to the echo signal from the fixed reflector phantom by changing the amount of delay.