JPH04208141A - Ultrasonic diagnosis device - Google Patents

Abstract

PURPOSE:To enhance the mobility of a probe by transmitting signals on a transmission line between the probe and a main body, giving homodyne detection to a signal received from each vibrator, and processing the detected reception signals through composition and addition. CONSTITUTION:In a probe 20, vibration elements are driven one by on in turn to send and receive waves. From the probe 20 to a main body, a scanning start terminal signal, a transmission waveform signal and a reception signal are each transmitted serially by turns. The signals transmitted to the main body are each separated into three signals by a separation means 38. The separated reception signals are detected in homodyne detection as an example by using the separated transmission waveform signal. The separated signals are composed and added in an opening composition method, and then once stored in a frame memory and further displayed on a display 52.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to ultrasonic diagnosis in which transmission between an ultrasonic probe and an ultrasonic diagnostic device is carried out serially, and signal processing is performed using an aperture synthesis method. A flash appears on the device.

[Prior Art] Ultrasonic diagnostic apparatuses that use ultrasound to obtain tomographic images of in-vivo images are used in the medical field.

FIG. 5 schematically shows signal transmission between an ultrasound probe (hereinafter referred to as a probe) and an ultrasound diagnostic apparatus main body (hereinafter referred to as a main body).

In FIG. 5, an array transducer 10 provided on the probe
is composed of a plurality of vibration elements 10a.

By driving each of the vibrating elements 10a, ultrasonic waves are transmitted and reflected waves from within the living body are received.

As shown in the figure, the reflected wave from the focal point F is received by each vibrating element 10a, and each received signal is independently transmitted to the main body via the probe cable 11.

Then, each transmitted received signal is transmitted through a delay line 14.
A delay is applied to each signal independently, and the respective signals are combined by an adder 16.

“Problems to be Solved by the Invention” As described above, in the conventional ultrasonic diagnostic device, a large number of transmission lines 12 are required between the probe and the main body, which makes it difficult to operate the probe. There was a problem that caused a hindrance.

That is, in the past, the probe cable was
Since it is composed of zero or more signal cables, its diameter increases and its weight increases, and as a result, the movement of the probe that comes into contact with the living body is restricted.

Therefore, in Japanese Patent Application Laid-Open No. 59-156334, an ultrasonic diagnostic method is proposed in which the probe and the main body are connected by a multi-core cable consisting of a large number of optical fiber cables, and the probe and the main body are connected by high-speed digital optical transmission. Equipment is shown.

However, since this ultrasonic diagnostic apparatus requires high-speed conversion in units of GH2, the circuit becomes complex depending on the number of transmission lines, which poses a problem when housed in a small probe.

Further, examples of devices that perform transmission between the probe and the main body in one line include devices disclosed in Japanese Patent Laid-Open No. 63-286140.

In this device, a plurality of delay lines shown in FIG. 5 are housed inside the probe, and the added signals are transmitted to the main body.

However, in the case of this device, since a large number of delay lines are housed inside the probe, the probe itself becomes large and heavy.

The present invention has been made in view of the above-mentioned conventional problems,
The purpose of this is to improve the operability of the probe by transmitting data between the probe and the main body using a single transmission means, and also to easily obtain accurate tomographic image information on the main body side. Our goal is to provide an ultrasonic diagnostic device that can

Another object of the present invention is to provide an ultrasonic diagnostic apparatus in which the probe is cordless.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a scanning means for sequentially driving each vibrating element of an array vibrator one by one to transmit and receive waves, and a scanning means for repeatedly scanning the scanning means. A scanning start end signal related to the above, a transmission waveform signal obtained by branching the transmission drive signal supplied to each of the vibration elements, and a reception signal from each of the vibration elements are sequentially transmitted serially in a predetermined order. a transmission means, a signal separation means for separating the three transmitted signals, and mixing a detection reference signal created by delaying the separated transmission waveform signal in stages into the separated reception signal. , a detection means for outputting a signal having a positive or negative sign according to the product of the phase difference and amplitude of the two, and means for synthesizing and adding the detected signals, the detection means for outputting a signal having a positive or negative sign according to the product of the phase difference and amplitude of the two, and means for performing synthesis and addition of the detected signals, a synthesis control means for synthesizing and adding signals whose one round trip distance to the focus falls within a predetermined wavelength range; a frame memory for storing the synthesized and added signals; and a signal stored in the frame memory. A display device that displays the following.

Further, the present invention is characterized in that the transmission means transmits signals between the ultrasound probe and the main body of the ultrasound diagnostic apparatus using radio waves, light waves, or ultrasound transmission waves.

Furthermore, the present invention is characterized in that a probe power supply section and a transmission transmitter are provided separately from the ultrasonic probe.

[Operation] According to the above configuration, first, in the probe, each vibrating element has one
They are sequentially driven one by one to transmit and receive waves.

Then, a scanning start signal, a transmission waveform signal, and a reception signal are serially transmitted from the probe toward the main body.

Here, it is also possible to use light, radio waves, ultrasonic waves, etc. for the transmission.

The signal transmitted to the main body is separated into three signals by the separation means.

Then, the separated received f2 signal is subjected to, for example, homodyne detection using the separated transmitted waveform signal.

The detected signals are combined and added based on the aperture synthesis method, and then temporarily stored in a frame memory and further displayed.

Therefore, transmission is possible between the probe and the main body using a single transmission line, and even if the transmission is performed using ultrasonic waves, for example, the transmission can be easily performed.

Furthermore, on the main body side, the received signals from each vibrating element are synthesized by the aperture synthesis method, making it possible to obtain tomographic information with high accuracy.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a specific configuration of an ultrasonic diagnostic apparatus according to the present invention.

First, each component provided in the ultrasonic probe 20 will be explained.

The trigger oscillation circuit 22 generates basic transmission pulses, and in this embodiment generates trigger pulses at a repetition frequency of 5 kHz.

The pulses generated by the trigger oscillation circuit 22 are input to a pulse generation circuit 24. This pulse generation circuit 24 generates a 3MH pulse in synchronization with the input pulse, that is, at the repetition frequency of the pulse generated by the trigger oscillation circuit 22.
A transmission pulse of about 100V is generated at z. Specifically, a pulse transmission drive signal having a width of about 167 nS, which is the positive part of the 11th period of a rectangular pulse whose one period is 333.3 nS, is generated.

Then, this transmission drive signal is sequentially sent to the array transducer 26 via the switch 25, and a portion is sent to the time division multiplexer 28.
is supplied as a transmission waveform signal to

Here, the switch 25 switches and supplies the transmission drive signal to each vibration element related to wave transmission and reception one by one.

The array vibrator 26 has a plurality of vibrating elements arranged in an array I, and in this embodiment, it is composed of 256 vibrating elements. The interval between each vibrating element is a pitch of Q-0.3 mm, and the array vibrator 1 is approximately 0.3 mm pitch.
．． It is formed with a length of 3×256=7.7 cm.

In the present invention, each vibrating element is driven one by one, so when the transmission drive signal is supplied, the ultrasonic waves emitted from the k-th vibrating element are transmitted widely within the body, as shown in FIG. The reflected waves from each tissue are received by the same vibrating element, that is, by the vibrating element No. 1''.

Here, in this example, since waves are transmitted sequentially at a pulse repetition frequency, the period between the two transmissions is used as reception time, and as a result, since the repetition frequency is 5 kHz, the period is is 072 m5, and therefore data can be captured within a range of approximately 15 cm from the vibrating element.

Then, the switch 25 sequentially switches each vibration element,
The 1st vibrating element to the 256th vibrating element 11 are sequentially driven, and this process is repeated.

The time division multiplexer 28 provided in the probe 20 has −1(
, ) - The trigger oscillation circuit 22 supplies the scan start signal a related to the scanning of the vibrating element, and the transmission drive signal from the pulse generation circuit 24 branches 1. A width transmission waveform signal, which is a transmission drive signal with a small amplitude, is supplied.

Furthermore, a reception signal C received by each vibrating element of the array vibrator 26 is sequentially supplied from the switch 25.

The time division multiplexer 28 then sequentially sends the three signals a, b, and c sent to the modulator 30.

Specifically, a, b, c, b, c, b, c, -.

The data is sent out as b, c, and after one more scan is completed [7], it is sent out again as a, b, c, b, c, . . . from the beginning.

In this case, the received signal C is sent to each vibrating element in turn.

Then, in the modulator 30, the received time division multiplexed signal is subjected to amplitude modulation or frequency modulation 17, for example, and is sent to a transmission wave transmitter 32.

-11,- Here, in order to make the probe 20 cordless without performing line transmission in this embodiment, the transmission transmitter 32
A method of transmission using ultrasonic waves is adopted. Of course, radio waves or light may also be used.

Here, in this embodiment, although not shown, each component is driven by a battery provided inside the probe 20. In practice, since a considerable amount of electric power is required, it is preferable to provide a power supply unit provided separately from the probe.

It is also preferable that the above-mentioned transmission transmitter 32 is configured separately from the probe 20 and integrated with the power supply section, thereby making it possible to reliably and stably transmit each signal. Become. Here, by configuring the power supply line between the power supply section and the probe 20 and the communication cable between the separately provided transmission transmitter in one direction, the probe It is possible to improve the operability of Furthermore, it is preferable to provide the modulator 30 and the like outside the probe for the reasons mentioned above.

Next, the main body of the ultrasonic diagnostic apparatus will be explained.

In the figure, 34 is a transmission wave receiver, which receives the signal transmitted from the transmission wave transmitter 32 described above. In this example, a receiver for transmitting ultrasonic waves is installed.
).

The transmission reception signal received by the transmission receiver 34 is sent to a detection amplifier 36.

This detection amplifier 36 demodulates the signal modulated by the modulator 30 and further amplifies it.

The processed signal is then sent to the signal separation circuit 38.

This signal separation circuit 38 separates the signals time-division multiplexed by the time-division multiplexer 28. That is, the above-mentioned scanning start signal a, the transmission waveform signal S, and the reception signal C of each vibrating element are separated.

Of these three separated signals, the transmission waveform signal is input to the delay circuit 40.

This delay circuit 40 inputs the input transmission waveform signal and delays it in stages (j, the delay -12-).

The output signals are outputted to output terminals number 1 to N=512. Specifically, "double 3 M H
The pulse waveform with a width of 150 ns, which is slightly smaller than the pulse with a width of 167 ns, which is the positive part of the half-wave transmission waveform of z, is
Each output is output from two output terminals. This 150
The time nsxN is equivalent to the time required for the ultrasonic transmission signal transmitted from the transducer to propagate back and forth over the distance from the transducer to each tissue in the living body. That is, in this embodiment, this 150 nsXN corresponds to the round trip propagation time of the ultrasonic wave over a distance of about NX0.11 mm.

In this example, if n=512, the diagnostic distance for ultrasonic diagnosis is 0.11 mm x at most.
512 signals (reference signals) are 5.6 cm, and to cover a larger area, increase N by 0°.The 512 signals (reference signals) sent from the delay circuit 40 are sent to the homodyne detector group 42. has been done.

On the other hand, the other input terminal of the homodyne detector group 42 is supplied with a receiver (B (ii M'') separated from the signal separation circuit 38.

Then, in this homodyne detector group 42, homodyne detection is performed in time series based on the 512 reference signals inputted in pairs to the received signal C.

After such homodyne detection is performed, the 512 output terminals of the homodyne detector group 42 output delayed b
Phase difference between the signal and the currently arriving C signal, Part 1]
A signal having a positive or negative sign is output according to the product of mutual amplitudes of the signals C and C.

In other words, this detected signal is determined by the difference in phase and amplitude of the received signal relative to the transmitted signal reflected from the tissue at each distance of the living tissue, the circumference with the distance from the transceiver element as the radius. It contains relative information. And part 5
Each of the 12 signals is input to the memory element group 44, respectively.

As shown in FIG. 3, this memory element group 44 is integrally composed of 512 memory elements for 256 transducers, that is, 512 x 256 = 131,072.
It is something that

Therefore, in this storage element group 44, 512 signals output from the homodyne detector group 42 are stored in time series for each received signal of each vibrating element.

Here, writing to the memory element group 44 is performed at the scan start point (≦a) output from the signal separation circuit 38.

It is controlled by the storage control circuit 46 to which the transmission waveform signal is input, and is performed in an orderly manner.

In this way, the memory element P! Each received signal stored in 144 is read out by a combination control circuit 48 and sent to a combination frame memory 50 based on a combination addition and performance percentage, which will be described later.

Here, the scanning start peak number a and the transmission waveform signal S are supplied to the synthesis control circuit 48 as described above, and the synthesis control circuit 48 performs its control based on these signals.

Then, each received signal stored in the composite frame memory 50 is read out in sequence and displayed on the display 52, thereby forming a tomographic image.

The ultrasonic diagnostic apparatus according to the present invention has the above configuration,
The aperture synthesis method will be described in more detail below.

FIG. 3 shows the concept of storing the detected received signal that reaches the storage element group 44.

Here, the address of each vibrating element of the array vibrator 26 is shown in the vertical direction, and the address of the number of elements in the storage element group 44, that is, 5]2 is shown in the horizontal direction.

In other words, each detected received signal output from the homodyne detector group 42 is stored in such a matrix configuration of addresses.

Specifically, for the 7th and 11th transducer elements (shown in Figure 2), the received information reflected at the nearest point to the transducer element is stored in nh2 The reflected waves from the tissue are sequentially e.g. nk, 2...
is stored in In other words, the circumference at the same distance from the vibrating element.”
The two pieces of tissue information are collectively stored in one storage element at one coordinate in the matrix. In FIG. 2, this is shown as a cross-sectional circle.

Next, signals are read out from the storage element group 44 stored in this manner as follows.

Now, the transmission and reception of waves from number 1 to number 11 is carried out as described above, and is stored in memory elements from number 1 to number 11, and in memory elements from number K to number 256. It is assumed that the signal from the previous scan is retained.

Regarding the distance circumference associated with propagation from the vibrating elements of each row from No. 1 to No. 11, for example, in Fig. 4, when transmitting and receiving waves to the vibrating elements, the signal of N, 11 is the distance where the Nkh point exists. If the signal is from the circumference of Ckb, which is a cut, and corresponds to the distance Ag when seen from point Nkh on the circumference of C or the surface h of G, then the memory system rN,
The storage signals of N, 1. signal. In this way, the distances from each transducer from number 1 to number 11 excluding number 1, and from number 111 to number 512, are each at a corresponding distance under the same conditions as point N1. Add the signal N at the point l&=J responsive memory element n.

gl gl Therefore, for each Nkh point, if the spacing between the array elements of the probe is Bgk and the wavelength is 1-1 as λ, as shown in Fig. 4, the notation h corresponding to the point Nkh corresponding to the distance C is The signal of the corresponding memory element n of the point N from G corresponding to the distance #EAg□ to be added to the memory element "kh" is the following gl
It is sufficient if it is a signal of the correspondence memory search -r of the point with the distance R1 determined by the relationship of the gl expression.

However, the distance Ck1. When we determine the radius of the sphere in N steps, in the example 512 steps, in Equation 1, the distance of 512 steps from G and the calculated value of R1 do not necessarily match any value of 512 steps. . Therefore, the condition A is that the phase difference is within 45 degrees for round trip distance and 22.5 degrees for one way distance.
For the distance of , gl round trip distance is 17 and the phase range is λ/8, the next one-way condition within this range is A , >R, -λ/16 gl gl A , <R, 10λ/16 gI gl is not satisfied, the distance A, N, the point, and the correspondence of that point g1
11; Incorporate the signal value of the 1 storage element n into the composite addition.

gl The spacing B between the array elements of the transducer of the probe shown in Figure 4 is known, and then the maximum distance limit is determined from the 512-step delay amount for the observation depth and diagonal distance range for the living body. If you decide, the corresponding distance R2 at each stage will be Akh
is known, and therefore, for each element, the diagonal distance from other elements to each N stage point is also known, and from this, the mutual relationship between each N point as to whether or not to perform addition for synthesis is also known. Become.

As a result, the signals at each distance stage of the other array elements that have finished transmitting and receiving waves are set at the distances mentioned above, compared to the signal at the time series point of the N stage distance of the signal currently being transmitted and received. By adding only the stored signals that meet the conditions for addition based on the relationship, signals can be synthesized in real time.

As described above, in the present invention, since it is possible to realize the transmission using a single line transmission path between the probe and the main body, it is possible to make the probe cordless, and it is also possible to make the probe cordless. This has the effect of improving the operability of the touch panel.

In addition, even if the transmission path is limited to one line, the main body can analyze the received information with high precision based on the aperture synthesis method, so it is possible to obtain tomographic images similar to conventional ones. .

[Effects of the Invention] As explained above, according to the present invention, signals can be transmitted between the probe and the main body through one transmission line, and the received signals of each transducer are subjected to homodyne detection and then synthesized. Since signal processing can be performed by addition, the maneuverability of the probe can be improved, and for example, it is possible to arrange the probe and the main body at a distance from each other.

In addition, by making the probe cordless, it is possible to further improve its mobility, and it is now easier to contact areas such as the side of the body, which were traditionally restricted by the probe cable. It is possible.

Furthermore, according to the present invention, for example, probes that could not be replaced conventionally due to the difference between the linear type and the convex type can be easily replaced by changing the program of the main body. It also has the effect of improving compatibility.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an ultrasonic diagnostic apparatus according to the present invention, FIG. 2 is an explanatory diagram showing ultrasound propagation from a specific vibration element, and FIG. 3 is storage of received signals in the storage element group 44. FIG. 4 is an explanatory diagram for explaining aperture synthesis, and FIG. 5 is a diagram of the operating principle of a conventional ultrasonic probe. 20 ... Ultrasonic probe 26 ... Array transducer 28 ... Time division multiplexer 32 ... Transmission transmitter 34 ... Transmission receiver 38 ... Signal separation circuit 40 ... Delay circuit 42 ... Homodyne detector group 44 ... Memory element group 46 ... Memory control circuit 48 ... Synthesis control circuit

Claims (3)

[Claims] (1) A scanning means for sequentially driving each vibrating element of the array vibrator one by one to transmit and receive waves, a scanning start signal related to repeated scanning of the scanning means, and a transmission drive signal supplied to each of the vibrating elements. Serial transmission means for serially transmitting a branched transmission waveform signal and reception signals from each of the vibrating elements in a predetermined order; and signal separation means for separating the three transmitted signals. , Mixing a detection reference signal created by delaying the separated transmission waveform signal in stages with the separated reception signal, and outputting a signal having a positive or negative sign according to the product of the phase difference and amplitude of the two. and a means for performing synthesis and summation of the detected signals, wherein one round trip distance from the vibrating element to the focal point of each of the detected signals satisfies a condition that the distance falls within a predetermined wavelength range. An ultrasonic diagnostic apparatus comprising: a synthesis control means that synthesizes and adds signals, a frame memory that stores the synthesized and added signals, and a display that displays the signals stored in the frame memory. . (2) In the ultrasonic diagnostic apparatus according to claim (1), the transmission means transmits signals between the ultrasonic probe and the main body of the ultrasonic diagnostic apparatus using radio waves, light waves, or ultrasonic waves. An ultrasonic diagnostic device characterized by: (3) The ultrasonic diagnostic apparatus according to claim (2), characterized in that a probe power supply unit and a transmission transmitter are provided separately from the ultrasonic probe. Ultrasonic diagnostic equipment.