JPS6246176B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic diagnostic apparatus used for medical diagnosis.

For example, in an ultrasonic diagnostic apparatus for cardiac diagnosis, a B-mode image is observed almost in real time using a so-called real-time method, that is, a high-speed scanning method such as an electronic scan method, and ultrasonic waves are applied to a desired location in the B-mode image. Techniques for obtaining Doppler images are commonly used.

In order to display these B-mode images and Doppler images, two types of X-Y monitors with different afterglow characteristics are used to display each image. I was trying to display it separately. That is, for real-time B-mode image display, a non-persistent X-Y monitor with a short afterglow time is used because the imaging scanning speed is high, and for Doppler image display, the image forming speed is slow. Therefore, a long afterglow or storage type X-Y monitor with a long afterglow time was used. Figure 1 shows the B-mode image and Doppler image in each
- This shows an outline of the display section of the ultrasonic diagnostic device when displayed on the Y monitor. In this case, the B-mode image IB is displayed on the non-persistence type X-Y monitor M1 as shown in the figure. , the Doppler image ID is displayed on the long afterglow type XY monitor M2.

By the way, understanding the relative relationship between these B-mode images and Doppler images, taking photographs of both images, and using VTR
Considering the convenience of recording images using a video tape recorder, it is far more preferable for these B-mode images and Doppler images to be displayed in parallel on the same screen rather than on separate screens. However, displaying these B-mode images and Doppler images in parallel on the same display screen on the same monitor is difficult due to the difference in afterglow characteristics required for the display mentioned above, and the simultaneous display of each image on the same display screen. Conventionally, this has been difficult to achieve due to the complexity of display scanning to achieve this.

In particular, since ultrasound Doppler images measure the velocity of movement of the heart wall, valves, etc., Doppler images alone are not often used, and in most cases, they are displayed together with B-mode or M-mode images for diagnostic purposes. Demonstrates the effect of For this reason, the Doppler image in particular is B
The mutual relationship with the mode or M-mode image is important, and it is desirable to display these on the same screen.

The present invention was made against the background of the above, and provides an ultrasonic diagnostic apparatus that can display Doppler images obtained by the ultrasonic Doppler method and ultrasonic images obtained by other ultrasound imaging methods in parallel on the same display screen. is intended to provide.

That is, the present invention is characterized by an ultrasonic wave transmitting/receiving means for transmitting an ultrasonic beam toward a subject and receiving an echo of the ultrasonic beam, and an ultrasonic wave supplied from the ultrasonic wave transmitting/receiving means. In an ultrasonic diagnostic apparatus equipped with a signal processing unit that processes echo signals to obtain Doppler information and B or M mode image data, (a) converting the Doppler information and B or M mode image data into digital signals; (b) a memory comprising first and second storage areas for separately storing the Doppler information and B or M mode image data supplied from the A/D converter; (c) write control means for separately writing the Doppler information and B or M mode image data supplied from the A/D converter into the first and second storage areas of the storage means; (d) readout control means for reading out Doppler information and B or M mode image data separately stored in the first and second storage areas of the storage means in television format; (e) this readout control means; a D/A converter that converts the Doppler information read out and the B or M mode image data into an analog video signal; a digital scan converter consisting of the above (a) to (e); and image display means for displaying an analog video signal supplied from the converter.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In this embodiment, a B-mode tomographic image obtained by an electronic linear scan method and a single-probe Doppler image of a predetermined site in this tomographic image are simultaneously displayed on the same screen in substantially real time.

First, the correspondence between the imaging ultrasound beam and the image storage memory in this embodiment will be explained with reference to FIGS. 2 and 3.

In FIG. 2, BP is a B-mode probe that transmits ultrasonic waves when capturing a B-mode image, and B indicates the ultrasound beam position scanned by the B-mode probe BP. The sound wave beam B is B ₁ ,
B ₂ , C ₃ , ..., B _N-1 , B _N , B _N+1 , ... B _M-1 , B _M
The echoes from inside the subject S are detected by the B-mode probe BP for each beam B ₁ to _{B M} by repeating scanning as shown in FIG. Write echo data. In this case, the frame memory FM is divided into a first area ME1 corresponding to the left half of the display screen and a second area ME2 corresponding to the right half of the display screen, and the first area ME1 is used in the B mode. Each of the ultrasound beams B ₁ to B _N to B _M is used for image data.
Memory areas are allocated as shown in the figure R ₁ to R _N to R _M corresponding to each B-mode display scanning line corresponding to the position, and the second area ME2 is for each B-mode display scanning line corresponding to the lapse of time for Doppler image data. Memory areas are allocated as indicated by DR ₁ to _DRL in the figure in correspondence with the scanning lines for Doppler display. Therefore, echo data based on echo signals obtained corresponding to each of the ultrasound beams B ₁ to B _M by the ultrasound beam scanning is transmitted to locations R1 to R corresponding to the B-mode display scanning line in the first region ME1. Write to _M. That is,
When the ultrasonic beam is scanned once from B ₁ to B _M , one image's worth of B-mode image data is written in the first region ME1. In B-mode real-time scanning, the ultrasonic beam scanning is repeated approximately several dozen times (at least approximately ten times) per second, and the data in the first area ME1 of the frame memory FM is updated substantially in real time.

On the other hand, DP shown in FIG. 2 is a Doppler probe (single probe), and this Doppler probe DP is integrally attached to the side of the B-mode probe BP via a support device DH. This Doppler probe DP is supported by the support device DH so that the position and direction of the Doppler ultrasound beam DB to be transmitted can be adjusted within the tomographic plane by the B-mode probe BP, and this support device The position direction of the ultrasonic beam DB is detected by the DH. The timing of measurement imaging using the Doppler method is as follows: (a) A method in which B-mode images and Doppler images are taken alternately in a short time span (for example, about one frame of B-mode images) (both images are captured in approximately real time). ) (b) A method can be considered in which the B-mode image is temporarily frozen and Doppler imaging is performed over a scheduled period of time (one display is in real time and the other is a frozen display), but here (b) B is considered. The method for freezing the mode will be explained. First, prior to Doppler image measurement and display, the B-mode image is frozen (writing to the frame memory FM is stopped), and then the Doppler measurement beam position and the Doppler measurement position on the beam are set. Doppler measurement beam position is Doppler probe
The Doppler measurement position is determined by the sampling timing of the echo signal, and the beam position mark MB and position mark MP are displayed on the B-mode image and observed. Make settings while doing so. In this way, the ultrasound beam DB is transmitted in a pulsed manner from the Doppler probe DP, Doppler information about the set area is obtained, and this is transmitted to the area corresponding to the Doppler display scanning line in the second area ME2 of the frame memory FM. Data is sequentially updated by sequentially writing to DR ₁ to DR _L and repeating this process. In this case, as a Doppler image, for example, Doppler displacement information about the set part is transformed into a Fast Fourie Transformation (Fast Fourie Transformation ~
The frequency distribution image obtained by FFT) is used. In this way, Doppler displacement information about the set region is collected in the second region ME2 with B-mode scanning temporarily frozen, and its frequency distribution image is written in real time.

The data stored in the frame memory FM is read out and displayed in the first area ME1 and the second area ME2 at once, that is, by reading out and scanning over both areas ME1 and ME2, for example, in a so-called television format (television format). standard method of scanning),
Provide for display. Therefore, the appearance of the display screen approximately corresponds to the storage format of the frame memory FM shown in FIG.

FIG. 4 is a block diagram showing the specific configuration of this embodiment.

In FIG. 4, the B-mode probe BP is composed of a large number of unit oscillators T ₁ , T ₂ , ...T _K , and these unit oscillators T ₁ , T ₂ , ...T _K drive them. Each unit pulsar of pulsar part PL for
PL ₁ , PL ₂ ... are each connected to PL _K. The pulsar unit PL is composed of the unit pulsators PL ₁ , PL ₂ , ... PL _K and the transmission delay lines PDL ₁ , PDL ₂ , PDL _K that are individually connected in series to these unit pulsers. The input sides of ₁ to PDL _K are commonly connected and coupled to the basic control signal generator BCG. The pulser section PL is a unit pulser which is selectively driven by delaying the rate pulse outputted from the basic control signal generator BCG by a scheduled time by the transmission delay lines PDL ₁ to PDL _K , respectively.
It is applied to PL ₁ to PL _K to perform scheduled ultrasonic beam scanning, transmission beam focusing, etc. Delay time control of these transmission delay lines in the pulsar unit PL and unit pulsar PL ₁
The selection control of ~ _PLK is performed according to the output raster address signal of the raster address generator RAG which operates in response to the output rate pulse from the basic control signal generator BCG. Furthermore, the unit oscillators T ₁ , T ₂ , ...T _K of the B-mode probe BP are connected to the respective preamplifiers (preamplifiers) PA ₁ , PA ₂ , ... of the receiver RC for receiving and processing these received signals. Each is connected to PA _K. The receiver RC includes the preamplifiers PA ₁ , PA ₂ , ...PA _K and delay lines for wave reception that are individually connected in series to these.
It is composed of RDL ₁ , RDL ₂ , . . . RDL _K and an adder ADR that adds and synthesizes the outputs of these reception delay lines RDL ₁ to RDK _K. The receiver RC amplifies the echo reception signals received by the unit oscillators T ₁ to T _K of the B-mode probe BP, and delays them by the scheduled time by the reception delay lines RDL ₁ to RDL _K , respectively, and sends them to the adder ADR. The amplification and detection circuit performs focusing operation and synthesis of echo reception signals corresponding to beam scanning by adding
This is what we give to AMD. The output of the amplification detection circuit AMD is given to the digital scan converter DSC.

In addition, the Doppler probe DP has a Doppler detection section.
It is driven by the Doppler pulser DPL of the DID and provides the received signal to the amplifier AMP. Doppler detection unit DID
The figure shows the Doppler pulser DPL and amplifier.
In addition to AMP, first and second correlation circuits CD ₁ , CD ₂ ,
First and second low-pass filters LPF ₁ , LPF ₂ , first and second sampling and hold circuits SH ₁ , SH ₂ ,
It consists of first and second band pass filters and a range gate generator RGG. The Doppler pulser DPL generates the Doppler probe DP in response to the output rate pulse of the basic control signal generator BCG.
is driving. The output of the amplifier AMP is then given to the first correlation circuit CD ₁ and the second correlation circuit CD ₂ to which the rate pulse of the basic control signal generator BCG is also input. The output of the first correlation circuit CD ₁ is input to the first sampling and hold circuit SH ₁ via the first low-pass filter LPF ₁ , and the output of the second correlation circuit CD ₂ is input to the second low-pass filter LPF ₂ .
The signal is inputted to the second sampling and hold circuit _SH2 via. 1st and 2nd sampling hold circuit
The sampling timing of SH ₁ and SH ₂ is determined by the output range gate signal of the range gate generator RGG which responds to the rate pulse output of the basic control signal generator BCG. The outputs of the first sampling and holding circuit SH ₁ and the second sampling and holding circuit SH ₂ are supplied to the first bandpass filter BPF ₁ and the second bandpass filter BPF ₂ , respectively.
It is input to the fast Fourier transform circuit FFT via. The output of this fast Fourier transform circuit FFT is given to a digital scan converter DSC. The timing of the range gate by the range gate generator RGG corresponds to the position on the Doppler sound beam where Doppler information is collected.

The Doppler beam position signal detected by the support device DH that supports the Doppler probe DP is given to the mark display circuit MD. The mark display circuit MD includes the range gate generator RGG of the Dobra detection unit DID.
A range gate indicating the Doppler information collection position on the Doppler beam is also given, and the beam position mark MB and position mark explained in Fig. 3 are also given.
It is input to the digital scan converter DSC as a mark signal for displaying the MP.

And digital scan converter DSC
The output of is given to a TV (television) monitor TVM. The digital scan converter DSC has the above-mentioned frame memory FM built-in in the form of digital memory, and the basic control signal generator BCG.
Output rate of pulse, raster address generator
RAG raster address signal, amplification detection circuit AMD
In response to the echo signal output of the mark display circuit MD, the mark signal of the mark display circuit MD, and the Doppler image output of the fast Fourier transform circuit FFT, image data is read and written to the frame memory FM as described above in accordance with the raster address signal. Specifically, it is constructed as shown in FIG. 5, for example.

As shown in FIG. 5, the analog image signal input to the digital scan converter DSC, in this case the B-mode echo signal or Doppler image signal input, is an A/D (analog-to-digital) converter.
The ADC converts the data into digital data, the line buffer LB1 collects the data line by line (for example, echo signals corresponding to one ultrasound beam in the case of a B-mode image), and stores the data in the first area ME1 or the second area of the frame memory FM. Each is written in the area ME2 as described above. The data written to this frame memory FM is the frame memory
It is read out in accordance with the television format across both areas ME1 and ME2 in the FM, passes through a line buffer LB2, is converted into an analog value by a D/A (digital-to-analog) converter DAC, and is output as a video signal. The TC controls the operation of each part within the digital scan converter DSC, such as specifying the write address for the frame memory FM, according to the rate pulse output from the basic control signal generator BCG and the raster address signal output from the raster address generator RAG. This is a timing control circuit that controls mark display, etc. according to the mark signal from the mark display circuit MD.

Next, the operation of such a configuration will be described with reference to timing charts shown in FIGS. 6a-d and 7a-e.

Figure 6a shows the output rate pulse of the basic control signal generator BCG, and Figure 6b shows the raster address generator.
Included in the raster address signal output from RAG, when H (high level), B mode scanning, L
(low level), the mode select signal indicates D-enable, that is, Doppler information sampling; c in the figure is a raster address that is included in the raster address signal and specifies the transmitting and receiving ultrasound beam position by each rate pulse; d in the figure is amplification detection circuit
This is the echo signal output from AND. That is, the raster address signal output from the raster address generator RAG is composed of two types of signals: a mode select signal and a raster address.

Delay line PDL ₁ for wave transmission of pulser section PL
The delay time of PDL _K and the delay time of the receiving delay lines RDL ₁ to RDL _K of the receiver RC are set and controlled to a scheduled format corresponding to the raster address, that is, the beam position specified by the raster address generator RAG. Meanwhile basic control signal generator
The rate pulse output from the BCG is connected to the transmission delay line PDL ₁ whose delay time is set by the output raster address of the raster address generator RAG.
〜PLD _K , similarly drives the unit pulsar group (some of PL ₁ to PL _K ) specified according to the raster address, and drives the unit oscillator group of the probe P (T ₁ to _{T K} some of them) to cause the probe P to transmit an ultrasonic beam. The echoes of this ultrasonic beam are received by the same unit transducers as at the time of transmission, and sent to the receiver RC's corresponding preamplifier groups (some of PA ₁ to PA _K ) and reception delay line group ( RDL ₁ to RDL _K ), are added by an adder ADR, are applied to an amplification/detection circuit AMD, and are applied to a digital scan converter DSC as an echo signal as shown in FIG. 6d.

In addition, in order to obtain a Doppler image, the mode select signal in the raster address signal is set to L as shown in FIG.
(low level), that is, D-enable.
At this time, a rate pulse as shown in Figure 7a is sent from the basic control signal generator BCG to the Doppler detector DID.
given to the pulsar DPL for Doppler. The Doppler pulser DPL excites the Doppler probe DP in accordance with the rate pulse and transmits an ultrasound beam into the subject S. Then, the received echo signal received by the Doppler probe DP is given to the first and second correlation circuits CD ₁ and CD ₂ via the amplifier AMP, and is phase-detected, respectively. First and second correlation circuits CD ₁ ,
The phase detection output from CD ₂ is filtered by first and second low-pass filters LPF ₁ and LPF ₂ , respectively. Then, a seventh
By the output range gate signal of the range gate generator RGG as shown in Figure c, the outputs of the first and second low-pass filters LPF ₁ and LPF ₂ are sampled and held in the first and second sampling and hold circuits SH ₁ and SH ₂ , respectively. This results in a waveform as shown in FIG. 7d. The outputs of the first and second sampling and holding circuits SH ₁ and SH ₂ are filtered by first and second band pass filters BPF ₁ and BPF ₂ , and then input to the fast Fourier transform circuit FFT.
The fast Fourier transform circuit FFT performs fast Fourier transform on the Doppler displacement signal and supplies it to the digital scan converter DSC as a frequency distribution signal as shown in FIG. 7e.

The digital scan converter DSC receives the B-mode echo signal from the amplification/detection circuit AMD, the Doppler display signal from the fast Fourier transform circuit FFT, the raster address signal (B-mode raster address and mode select signal) from the raster address generator RAG, and basic control. A rate pulse from a signal generator BCG and a mark signal from a mark display circuit MD are input. In the A/D converter ADC, either the B mode echo or the Doppler display signal is selected according to the H or L of the mode select signal, and the analog value is converted into a digital value. The converted signal is sent to the frame memory via line buffer LB ₁ .
Written to FM. The input signal selection and conversion timing in the A/D converter ADC, the operation timing of the line buffer _LB1 , and the write address and write timing of the frame memory FM are all controlled by the timing control circuit TC. Data is written to the frame memory FM in the first area ME1 when the mode select signal is H.
A B-mode image is written in the second region ME2, and a Doppler image is written in the second region ME2 when the mode select signal is L (D-enable). On the other hand, the data written in the frame memory FM is repeatedly read out in television format (by reading scanning across both the first area ME1 and the second area ME2) between data writing, and is converted into an analog video signal. Given to TV monitor TVM. Therefore, on the screen of the TV monitor TVM, the B-mode image and the Doppler image are displayed in almost real time (the image that is being written and updated at that time), in the same way as the format in the memory shown in Figure 3. are displayed in parallel. In addition, digital scan converter
The timing control circuit TC of the DSC is supplied with a rate pulse, a mode select signal, and a raster address as well as a mark signal from a mark display circuit MD.
A beam position mark MB and a position mark MP are written on the B-mode image by assigning predetermined specific gradation data to an address corresponding to a required mark position in the area ME1, and the beam position mark MB and position mark MP are displayed on the B-mode image.

In this way, the B-mode image and the Doppler image are displayed side by side on the same screen, making it easier to compare and contrast them and improving diagnostic ability. Since the Doppler image is recorded, the recording process becomes easier and the diagnostic value of the record increases.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings, but can be implemented with various modifications without changing the gist thereof.

For example, in the above embodiment, a B-mode image obtained by an electronic linear scan and an ultrasound Doppler image obtained by fast Fourier transforming a frequency distribution image obtained by fast Fourier transforming Doppler phase displacement information obtained by a single probe are stored in the first and second frames of the frame memory FM. The areas ME1 and ME2 are stored in parallel, and these are read out all at once and displayed in parallel on the same screen. However, as a means of capturing a B-mode image, it is possible to capture an image using a B-mode image capturing method other than electronic linear scan. A Doppler image capturing means other than the above-mentioned method may be used as a means for capturing a Doppler image, and a B-mode image or other ultrasound image may be displayed in parallel with the Doppler image instead of the B-mode image. Also good. When a Doppler image and an M-mode image are displayed in parallel, both can be displayed in real time.

As detailed above, according to the present invention, there is provided an ultrasonic diagnostic apparatus that can display a Doppler image obtained by the ultrasonic Doppler method and an ultrasonic image obtained by another ultrasonic imaging method in parallel on the same display screen. Can be done.

Therefore, just by looking at one and the same screen, a Doppler image and its related B-mode image or M-mode image can be viewed. Moreover, when recording with photographs or VTRs, each image can be recorded on the same film or tape, making it easy to associate each image when viewing it again.

In particular, a VTR can directly store video signals read out in television format. When displayed, the Doppler information and B/M mode image data are displayed without flickering because they are displayed in the above-mentioned television format, making image observation and diagnosis easier.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining a display method in a conventional device, and FIGS. 2 and 3 are diagrams for explaining an imaging method and data storage format in a frame memory in an embodiment of the present invention. FIG. 4 is a block diagram showing the configuration of the same embodiment, FIG. 5 is a block diagram showing the main structure of the same embodiment, and FIGS. 6 a to d and 7 a to e are for explaining the same embodiment. It is a waveform diagram of each part. BP...Probe for B mode, _T1 to _TK ...Unit oscillator, PL...Pulser part, _PL1 to _PLK ...Unit pulser,
PDL ₁ to PDL _K ...Delay line for transmitting waves, RC...Receiver, PA ₁ to PA _K ...Preamplifier, RDL ₁ to RDL _K
...Delay line for reception, ADR...Adder, AMD
…Amplification detection circuit, DSC…Digital scan converter, BCG…Basic control signal generator, RAG…
Raster address generator, TVM...TV monitor,
ADC...A/D converter, LB ₁ , LB ₂ ...Line buffer, DAC...D/A converter, FM...Frame memory, TC...Timing control circuit, DP...Doppler probe, DH...Support device, MD...Mark display Circuit, DID...Doppler detection unit, DPL...Doppler pulser, AMP...amplifier, CD ₁ , CD ₂ ...first and second correlation circuits, LPF ₁ , LPF ₂ ...low pass filter,
BPF ₁ , BPF ₂ ...Band pass filter, SH ₁ , SH ₂
…Sampling hold circuit, RGG…Range gate generator, FFT…Fast Fourier transform circuit.

Claims (1)

[Claims] 1. Ultrasonic wave transmitting/receiving means for transmitting an ultrasonic beam toward a subject and receiving echoes of the ultrasonic beam, and an echo signal supplied from the ultrasonic wave transmitting/receiving means as a signal. In an ultrasonic diagnostic apparatus comprising a signal processing unit that processes Doppler information and obtains B or M mode image data, (a) an A/D that converts the Doppler information and B or M mode image data into digital signals; a converter; (b) storage means comprising first and second storage areas for separately storing the Doppler information and B or M mode image data supplied from the A/D converter; (c) ) write control means for separately writing the Doppler information and B or M mode image data supplied from the A/D converter into the first and second storage areas of the storage means; (d) the readout control means for reading out Doppler information and B or M mode image data separately stored in the first and second storage areas of the storage means in television format; a D/A converter that converts the Doppler information and B or M mode image data into analog video signals; a digital scan converter consisting of the above (a) to (e); 1. An ultrasonic diagnostic apparatus comprising: image display means for displaying an analog video signal.