JPH0221851A - Ultrasonic device - Google Patents

Abstract

PURPOSE:To grasp a portion where abnormal blood flow occurs by simultaneously reading out stored tomographic signal and Doppler image signal and displaying real time two-dimensional tomographic image and real time two-dimensional Doppler image in such a manner to lie one on top of another. CONSTITUTION:Ultrasonic beams are transmitted and received twice in the same direction to detect the blood flow speed in that direction, and sequentially the transmitting and receiving directions of ultrasonic beams are switched under the control of a control circuit 7 and scanned to obtain two-dimensional tomographic image and two-dimensional Doppler image in a short time. When an image data input switching device 13 is connected to A contact point side, the tomographic image data is stored in a memory 14 and when it is connected to B contact point side, the Doppler image data is stored in the memory 14. When the control for switching the input switching device 13 and the control for writing and reading data in and from the memory 14 are made by a control circuit 16, two-dimensional tomographic image data and Doppler image can be taken in substantially in real time. Further, in order to simultaneously display the two-dimensional tomographic image and Doppler image in such a manner as to lie one on top of another, two sets of memories for tomographic image and Doppler image are provided in the memory 14, and the contents are simultaneously read out to be displayed on a display device.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an ultrasonic device, and particularly an ultrasonic device equipped with a mechanism for displaying a Doppler image (blood flow velocity distribution image) in real time (very short time). This invention relates to an ultrasonic device.

[Prior art]

Conventionally, ultrasonic pulsed Doppler technology has been used to measure, for example, the velocity of blood flow.

In other words, when ultrasonic waves are emitted from the skin toward the blood vessels inside the subject using a probe with a single transducer, waves are reflected from the blood cells in the blood vessels as well as reflected waves from the organ tissues inside the subject. can get. The reflected wave from this blood cell is [6L
The frequency of the transmitted ultrasound changes depending on the flow of blood within the tube.

The difference in frequency between the emitted ultrasonic wave and the reflected wave, that is, the ultrasonic Doppler deviation frequency f d (f d = f, −fl
=2Vcosθ·f+/c, where fo=frequency of the emitted ultrasonic wave, f the frequency of the reflected wave, and C: the speed of sound in the medium.

V: the speed of movement of the reflector; θ: the angle between the direction of the ultrasonic pulse and the direction of movement of the reflector) to measure the blood flow velocity.

[Problem to be solved by the invention]

To determine the ultrasound Doppler deviation frequency fd using the above-mentioned probe with a single transducer, 1 of the ultrasound Doppler frequency
The direction of the ultrasonic beam, that is, the probe, must be fixed for a period longer than the period. In order to two-dimensionally display blood flow velocity distribution and the like on a cross section, a Doppler sample position detection mechanism is required. Furthermore, since it takes time to scan the probe, there are problems such as the need to trigger an ECG or the like in order to apply it to a living body. Therefore, it has been impossible to display a blood flow velocity distribution image in real time as a two-dimensional image corresponding to a cross section of the subject.

The present invention provides the above-mentioned I? This was done in order to eliminate the FINi point.

An object of the present invention is to provide an ultrasound apparatus that can display a real-time two-dimensional tomographic image and a real-time two-dimensional Doppler image in a superimposed manner.

Another object of the present invention is to enable efficient scanning;
Another object of the present invention is to provide an ultrasonic device capable of displaying a two-dimensional distribution image (two-dimensional Doppler image) of blood flow velocity corresponding to a cross section of a subject in real time.

[Means to solve the problem]

The above object is achieved by an ultrasound device equipped with the technical means described below.

That is, an object of the present invention is to provide a single high-speed electronic scanning probe that transmits and receives ultrasonic waves, and a single high-speed electronic scanning probe that transmits and receives ultrasonic waves, and a single high-speed electronic scanning probe that transmits and receives ultrasound waves to a predetermined region with blood flow, such as the heart or blood vessels, in a subject per scan. an ultrasonic scanning means that transmits and receives an ultrasonic pulse beam several times per direction and scans while shifting the transmission and reception direction;
A tomographic image signal is obtained from each received signal, and the amount of phase change corresponding to the Doppler deviation frequency is detected using a delay circuit that delays one period of transmission and reception using the plurality of received signals rJ1 per direction. means for obtaining Doppler image signals at each depth within the subject; storage means for storing the tomographic image signals and Doppler image signals from each transmission/reception direction; This is achieved by an ultrasound apparatus whose main feature is that it is equipped with means for simultaneously reading out image signals and displaying a real-time two-dimensional tomographic image and a real-time two-dimensional Doppler image corresponding to this tomographic image in a superimposed manner.

[Effect]

According to the means for achieving the above object, an ultrasonic pulse beam is transmitted multiple times in one direction from a high-speed electronic scanning probe, a reflected signal is received for each transmitted wave, and one of the reflected signals is
tomographic data.

Then, by scanning while sequentially shifting the ultrasound transmission/reception direction while detecting the amount of phase change corresponding to the Doppler deviation frequency from the blood flow within the subject between each reflected signal,
Tomographic image data and Doppler signal data in each wave transmission/reception direction can be obtained almost in real time. Then, by storing these data in a storage means and reading them out simultaneously, a two-dimensional tomographic image and a two-dimensional Doppler image (
Two-dimensional blood flow velocity distribution images) can be superimposed and displayed in almost real time. By superimposing and displaying the two-dimensional Doppler image and the two-dimensional tomographic image, it is possible to easily and accurately grasp the location where abnormal blood flow occurs, which is extremely effective in terms of diagnosis.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An ultrasonic device according to a preferred embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block configuration diagram for explaining the schematic configuration of an ultrasonic device according to an embodiment of the present invention.

In Fig. 1, 1 is a probe capable of high-speed electronic scanning, preferably an electronic sector type probe, and 2 is an electronic switch circuit, which performs high-speed scanning by switching the transmission and reception of the transducer at high speed. It is for. 3 is a transmitting/receiving circuit, and 4 is a delay circuit for phasing the received signal.

5 is a phase synthesis amplifier, 6 is a detection circuit, and 7 is the electronic switch circuit 2. A control circuit 8 is a delay circuit that controls the sweep signals of the delay circuit 4 and the CRT display device 15. This is to apply a time delay of one cycle of the sound wave launch. Reference numeral 9 denotes a 90 degree phase shift circuit for shifting the phase of the output of the phase synthesis amplifier 5 by 90 degrees.

10A and IOB are limit amplifiers, 11 is a phase detection circuit, 12 is a low band pass filter, 13 is an image data input switch for inputting tomographic image data and Doppler image data to the memory 14, and the A contact side is The tomographic image data and the Doppler image data from the B contact side are input into the memory 14, respectively. The memory 14 is.

Output signal of the low band pass filter 12 or detection circuit 6
It is used to store the output signal of.

15 is a CRT display device, and this CRT display device 15
The horizontal (X) and vertical (Y) sweep signals are outputted from the control circuit 7 in the same direction as the beam direction of the ultrasonic pulse. A control circuit 16 controls switching of the image data input switch 13 and controls writing and reading of the memory 14.

FIG. 2 is a waveform diagram for explaining the phase change amount detection operation of the received signal in the fifth embodiment.

In Fig. 2, a is the output signal of the phase synthesis amplifier 5, and the received signal (echo signal) A of the fixed object and the received signal (echo signal) of the moving object at the time of transmitting and receiving the n-th ultrasonic pulse are in phase. It is a composite of nine things.

b is the output signal of the delay circuit 8, which is the received signal (echo signal) of the fixed object at the time of transmitting and receiving the n-1th ultrasonic pulse.
A and the received signal (echo signal) of the moving object are phase-combined.

C is an output signal of the 90 degree phase shift circuit 9, which is shifted in phase by 90 degrees from the signal port.

d and e are the output signals of the limit amplifiers IOA and 10B, f is the output signal of the phase detection circuit 11, and g is the output signal of the low band pass filter 12, respectively.

Next, the operation of the ultrasonic device of this embodiment will be explained.

In FIG. 1, a control circuit 7 outputs a launch clock along with focus data and ultrasonic pulse beam deflection data, and a delay circuit 4 outputs a predetermined type of launch clock to the ultrasound launch signal launched from the probe 1 according to the contents. A delay is applied.

For example, if there are 10 channels, there will be 10 different delays.

If there are 32 channels, 32 types of delays can be applied.

A high voltage pulse is output from the transmitter/receiver circuit 3 by these delayed launch signals, and is applied to a predetermined element of the probe l, so that an ultrasonic pulse beam is directed in a predetermined direction.
The waves are transmitted once at a time.

Each reflected signal of the ultrasonic beam emitted from the probe l is amplified by the transmitter/receiver circuit 3, aligned in phase by the delay circuit 4, synthesized by the phase synthesis amplifier 5, and detected by the detection circuit 6 to produce a tomographic image. It is output as a signal and input to the memory 14 via the A contact of the image data input switch 13.

As shown in FIG. 2, the output signal a of the one-way sum synthesis amplifier 5 is delayed by one cycle of ultrasonic wave launch in a delay circuit 8 in order to detect the blood flow velocity distribution, and then It is input to the amplifier IOA. Then, the output signal a of the phase synthesis amplifier 5 is shifted in phase by 90 degrees by a 90 degree phase shift circuit 9, and is input to the limit amplifier 1OB. At this time, the output signal C of the delay circuit 8 is the n-1th received signal, and the output signal C of the 90 degree phase shift circuit 9 is the nth received signal, so each of the limit amplifiers IOA, IOB
In the phase detection circuit 11, the output signals d and e have a pulse width corresponding to the phase difference, and the magnitude of the output voltage signal g of the low bandpass filter 12 is determined by the phase difference, that is, the reflector (blood flow).
It is possible to show the moving speed of Therefore, in order to detect the magnitude of the phase change of the received signal as the magnitude of the Doppler frequency, and to detect the amount of phase change, in this embodiment, the reflected signal at the time of transmission of the first ultrasonic pulse, which is a reference, is used. The ultrasonic beam is transmitted and received in the same direction multiple times, specifically twice, so that a reflected signal at the time of the second ultrasonic pulse transmission having a variation amount is obtained.

In this way, by transmitting and receiving an ultrasound beam twice in the same direction, the blood flow velocity in that direction is detected, and the transmission and reception direction of the ultrasound beam is sequentially switched under the control of the control circuit 7 for scanning. (high speed electronic scanning)
Two-dimensional tomographic images and two-dimensional Doppler images can be obtained in an extremely short time.

When the image data input switch 13 is connected to the A contact side, tomographic image data is stored in the memory 14, and when it is connected to the B contact side, Doppler image data is stored in the memory 14. Switching control of the input switch 13 and control of writing and reading from the memory 14 are performed by the control circuit 16. For example, in the receiving operation, for n-1 received signals, the input switch is moved to the A contact side. , for the n-th received signal, connect to the B contact side. This allows two-dimensional tomographic image data and two-dimensional Doppler image data to be captured almost in real time. In order to simultaneously display the two-dimensional tomographic image and the two-dimensional Doppler image in an overlapping manner, the memory 14 should be provided with two sets of memories, one for the tomographic image and one for the Doppler image, and the contents should be simultaneously read out and displayed on the display device. Bye.

As can be seen from the above description, according to the present embodiment, means for transmitting and receiving an ultrasonic beam multiple times in the same direction;
By having means for scanning and deflecting the ultrasonic beam using a high-speed scanning device, and means for detecting the amount of phase change proportional to the Doppler deviation frequency at each depth within the subject of the emitted ultrasonic beam. , it is extremely effective for diagnosis because it allows real-time two-dimensional Doppler images to be obtained.

For example, in the conventional ECG)-Hemlock method, the number of rusks is 100, and when repeating ultrasound pulses, it is 1! If you try to obtain a Doppler image with ff of 200 μsec, it will take 100 seconds (1) assuming the heartbeat period is 1 second, but according to this embodiment.

Since it can be obtained in 200μ5ecX2X100=40+*sec, it is possible to display an image of about 20 to 25 frames per lsec. Furthermore, since a high-speed electronic scanning device such as a high-speed electronic scanner is used, scanning can be performed efficiently.

Further, the present invention includes a memory for storing the amount of phase change and a memory for storing the tomographic image, and displays the real-time two-dimensional tomographic image obtained by the means and the real-time two-dimensional Doppler image in a superimposed manner. This is extremely effective in terms of diagnosis because the site where abnormal blood flow occurs can be easily and accurately identified. It goes without saying that the present invention is not limited to this embodiment, but can also be applied to inspection means for displaying tomographic images and flow velocity distribution images in fluid inspection, etc.

In the present embodiment, a method has been described in which the ultrasound beam is transmitted and received multiple times in one direction and scanned by sequentially shifting the transmission and reception directions, but the present invention is not limited to such a method. It is obvious that the method of determining the Doppler deviation frequency from the frequency difference between the emitted ultrasonic wave and the reflected wave and scanning by sequentially shifting the transmission and reception directions as described in the prior art described above may also be used.

〔Effect of the invention〕

As explained above, according to the present invention, a real-time two-dimensional Doppler image can be obtained, which is extremely effective for one diagnosis. Furthermore, by superimposing and displaying a real-time two-dimensional tomographic image and a real-time two-dimensional Doppler image, it is possible to easily and accurately grasp the location where abnormal blood flow occurs, which is extremely effective for diagnosis.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram for explaining the schematic configuration of an ultrasonic device according to an embodiment of the present invention, and FIG. 2 is a waveform diagram for explaining the phase change amount detection operation of a received signal according to the present embodiment. It is a diagram. In the figure, l... probe, 2... electronic switch circuit, 3
... Transmission/reception circuit, 4, 8... Delay circuit, 5... Phase synthesis amplifier, 6... Detection circuit, 7, 16... Control circuit, 9... 90 degree phase shift circuit, IOA , IOB...
Limit amplifier, 11. ...Phase detection circuit, 12...
-Low band pass filter, 13...image data input switch, 14...memory, 15...CRT display device. Patent applicant Hitachi Medical Co., Ltd.

Claims (1)

[Claims] (1) A single high-speed electronic scanning probe that transmits and receives ultrasonic waves, and multiple times per direction per scan to a predetermined region with blood flow such as the heart or blood vessels within the subject using the probe. an ultrasonic scanning means that transmits and receives an ultrasonic pulse beam and scans while shifting the direction of transmission and reception, and obtains a tomographic image signal from one reception signal per direction received by the ultrasonic scanning means; Using a delay circuit that delays one period of transmission and reception between multiple received signals per direction, the amount of phase change corresponding to the Doppler deviation frequency is detected to obtain Doppler image signals at each depth within the subject. storage means for storing the tomographic image signal and Doppler image signal from each transmission/reception direction; and a storage means for simultaneously reading out the tomographic image signal and Doppler image signal stored in the storage means to produce a real-time two-dimensional tomographic image and this tomographic image. An ultrasonic device characterized by comprising means for superimposing and displaying a real-time two-dimensional Doppler image corresponding to the image.