JP2763140B2 - Ultrasound diagnostic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an ultrasonic diagnostic apparatus including a reception delay unit for setting a plurality of reception focus areas for each ultrasonic echo to be received. About.

(Prior Art) As is conventionally known, a sector scan type ultrasonic diagnostic apparatus transmits an ultrasonic beam B to a living body by a vibrator 1 as shown in FIG. 4 to perform a sector scan. To obtain a tomographic image of a living body. In this sector scan type ultrasonic diagnostic apparatus, the transducer 1 is composed of a plurality of juxtaposed arrays, and a desired delay time is given to each of these arrays by a transmission delay unit (not shown). Then, the combined wavefront is converted into an ultrasonic beam focusing in an arbitrary direction, and the ultrasonic beam is scanned in a sector shape toward the living body.

Then, the ultrasonic beam reflected from the living body is received by the vibrator 1 as an echo signal, and a delay time is given by the reception delay unit to restore the transmission delay time for each array. Of the ultrasonic echoes are aligned.

At this time, as shown in FIG. 5, the reception beam is provided by a reception delay unit (not shown) as a reception delay unit such that a plurality of reception focus areas are divided and set as shown in, for example, (1) to (12). The reception delay time is controlled. Thus, the ultrasound scan is performed in a state where the focus is almost continuously adjusted from a shallow part to a deep part of the living body. The output signals of each channel in the vibrator 1 are added and output as one reception echo. Further, this signal is subjected to envelope detection, ultrasonic image information is detected, and output to the display unit as a B-mode image or an M-mode image.

Further, if necessary, the received echo is subjected to phase detection, blood flow information is detected, and is output to the display unit as a Doppler image.

FIG. 6 is a schematic configuration diagram showing a reception delay unit for setting the plurality of reception focus areas. In FIG. 1, a received echo input from a vibrator 1 (not shown) for each channel (for example, 64 channels) is branched to a first delay unit A and a second delay unit B. Here, the first delay unit A includes delay lines (for example, LC delay lines) 13-1A to 13-NA for each channel.
And a changeover switch that switches between them to obtain an arbitrary delay time
It has 12-1 to 12-NA. Also, the second delay unit B
It has delay lines 13-1 to 13-NB and changeover switches 12-1 to 12-NB.

Then, a signal indicating the reception focus area and the scan direction is input to the reception delay time control circuit 16. Further, the data of the required reception delay time is stored in advance in the memory circuits 14A and 14B, and when an address corresponding to a desired reception focus area is given from the control circuit 16 to the memory circuits 14A and 14B, the memory circuits 14A and 14B A switch control signal for obtaining a desired delay time is output to the changeover switches 12 and 13. The changeover switch 11 switches one of the delay units A and B and outputs a selected signal. The adders 15A and 15B add each echo to one.

In the device configured as described above, first, the first delay unit A sets the reception delay time so that the reception focus occurs in the area (1) in FIG. Receives acoustic echo. During this reception, the second delay section B sets the reception delay time so that the reception focus occurs in the area (2) in FIG. 6, and the changeover switch 11 is switched to the B side to transmit the ultrasonic echo. Receive the wave. In the same manner, by repeating such operations in the same manner, the reception focus can be set in the areas (1) to (12) in FIG. 5, so that the focus is almost continuously from the shallow part to the deep part of the living body. Can be obtained.

Further, the first or second delay section A,
After performing the operation of setting the reception delay time by any of B, the switching to this side is performed, so the switching noise generated when the changeover switches 12 and 13 in the delay units A and B are operated is displayed on the ultrasonic image. Will not be.

(Problems to be Solved by the Invention) By the way, in the conventional ultrasonic diagnostic apparatus described above,
As shown in the figure, at the repetition interval of the ultrasonic pulse for driving the vibrator 1, the interval between the reception focus areas is constant. That is, in a shallow part where the interval between the reception focus areas needs to be made smaller, the interval becomes too coarse. Conversely, in a deep part where the interval between the reception focus areas may be coarse, the interval is often too small. For this reason, especially in a shallow portion, the effect of the reception dynamic focus cannot be obtained as much as desired, and the image quality is deteriorated.

In order to improve this, there is a method in which the number of reception focus areas is increased and the interval between the reception focus areas is set to be smaller than before. However, this method had to use a lot of data for controlling the reception delay time. For this reason, there has been a problem that the hardware is enormous and complicated.

Therefore, an object of the present invention is to provide an ultrasonic diagnostic apparatus which can simplify the apparatus without increasing the scale of hardware and obtains an excellent ultrasonic image over a wide range from a shallow part to a deep part. is there.

[Structure of the Invention] (Means for Solving the Problems) The present invention has taken the following means to solve the above problems and achieve the object. The present invention transmits an ultrasonic wave to a living body and receives biological information such as a signal reflected by a discontinuous surface in the living body while setting a plurality of reception focus areas in an ultrasonic beam direction by a reception delay unit. In an ultrasonic diagnostic apparatus that obtains ultrasonic diagnostic information of a living body by processing this, an interval between a plurality of reception focus areas by the reception delay unit is finely set at an arbitrary depth, and Control means for controlling the number to be constant over the entire depth of field is provided.

The second invention is a person provided with control means for roughly setting and controlling the interval between the plurality of reception focus areas by the reception delay means as the depth of field becomes deeper.

According to a third aspect of the present invention, there is provided a control device for finely setting and controlling the interval between a plurality of reception focus areas by a reception delay unit in a shallow portion compared to a deep portion.

According to a fourth aspect of the present invention, there is provided a control device for finely setting and controlling an interval between a plurality of reception focus areas by the reception delay means at a selected depth.

(Action) By taking such means, the following action is exhibited. Since the interval between the reception focus areas can be set finely without changing the number of reception focus areas at the entire depth of field at an arbitrary depth, appropriate reception dynamic focus can be applied to a portion at an arbitrary depth, and a good super focus can be achieved. A sound wave image can be obtained, and the apparatus can be simplified without increasing hardware.

In addition, since the setting control can be performed so that the depth becomes wider as the depth of field becomes deeper, the receiving dynamic focus can be applied over a wide range from a shallow portion to a deep portion, and a good ultrasonic image can be obtained over a wide range. Is obtained.

Furthermore, since fine setting control can be performed at a shallow part compared to a deep part and setting control can be performed at a selected depth, it is possible to appropriately focus on a diagnostic part and obtain a good image.

(Embodiment) FIG. 1 is a schematic block diagram showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention, FIG. 2 is a connection diagram showing a specific configuration of a reception delay unit in the embodiment, and FIG. FIG. 4 is a diagram showing an ultrasonic image obtained by the above embodiment. As shown in FIG. 1, the ultrasonic diagnostic apparatus includes a transmitting system having a transducer 1, a pulser 2, and a transmission delay unit 3, a receiving system having a preamplifier 4, a reception delay unit 5, and a receiver 6 for obtaining a B-mode image. , A processing system having a Doppler detector 9 for obtaining Doppler information and a DSC 7, and a display 8
And a display system having

The feature of this embodiment is that the interval between the plurality of reception focus regions by the reception delay unit 5 as the reception delay unit that sets the plurality of reception focus regions with respect to the ultrasonic beam direction is finely set at an arbitrary depth. A control circuit 10 as setting means for setting and controlling the number of the plurality of reception focus areas to be constant over the entire depth of field;
The control circuit 10 includes a reception delay time control circuit 16 inside the reception delay unit 5 controlled by the control circuit 10.

Also, as shown in FIG. 3, the ultrasonic transmission beam is divided into, for example, four (a reception focus area) by the control of the reception delay unit 5 of the control circuit 10, and the interval between the reception focus areas is different in each part. Three set reception focus patterns (FIGS. 3 (1) to 3 (3)) can be selected.

That is, in the reception delay unit 5 shown in FIG. 2, the reception delay time control circuit 16 inputs a signal for selecting the reception focus pattern from the control circuit 10 as a control signal. A reception delay time control data generation circuit (not shown) generates reception delay time control data for obtaining a desired reception focus pattern when the reception focus pattern is selected.
The reception delay time control circuit 16 also includes an address indicating a reception focusing area and scanning direction that varies according to distance reception focusing area in reception focusing pattern set as shown in FIG. 3 FS _A, by the FS _B, optionally The memory circuit reads out the reception delay time control data for setting the reception focus area from the memory circuits 14A and 14B and sends it to the switch group 12 as a switch control signal.
Controls 14A and 14B.

The reception delay time control data is set so that the selected reception focus pattern is formed and the number of reception focus areas on the ultrasonic beam does not change.

Hereinafter, the operation of the ultrasonic diagnostic apparatus will be described with reference to the drawings. First, as shown in FIG. 1, a vibrator 1 is composed of, for example, 64 arrays, and each element is generated by a transmission delay unit 3 and amplified by a 64 channel pulsar 2 and has 64 channels of pulses having different delay times. Driven by Then, the wavefronts of the ultrasonic waves are generated from the respective elements of the vibrator 1 at different timings, and these are combined and transmitted as an ultrasonic beam in an arbitrary direction into the living body. By changing the delay time of the pulse given to each element,
The ultrasonic beam scans in a sector shape as shown in FIG. 1, and the ultrasonic beam is transmitted to the living body in that area.

Then, the ultrasonic beam transmitted into the living body is reflected by a discontinuous region between an organ and a tissue in the living body and the like, and is received by the vibrator 1 as an ultrasonic echo. Further, the ultrasonic echo output from each element of the vibrator 1 is amplified by the preamplifier 4 of 64 channels, and is set by the reception delay unit 5 so as to restore the delay time given to the echo of each channel at the time of transmission. Delay time,
The timing of the ultrasonic echo of each channel is aligned.
At this time, as shown in FIG. 3, the reception delay time is controlled by the reception delay unit 5 to which the control signal from the control circuit 10 is input so that a plurality of reception focus areas are set in the depth direction. Hereinafter, the operation of the reception delay unit 5 will be described in detail.

First, as shown in FIG.
At the point in time when the reception focus pattern is roughly selected as the interval between the plurality of reception focus areas becomes larger as the depth of field becomes deeper, the reception delay time control data for obtaining the desired reception focus pattern is generated by the reception delay time control data. This data is generated by the memory circuit 14A,
Transferred to 14B. And at the end of this transfer,
Setting receives focus area and address FS _A which indicate the scan direction that varies according to distance reception focusing area in reception focusing pattern, the FS _B, the control circuit
Generated by 16 and applied to memory circuits 14A and 14B. As a result, reception delay time control data for setting a desired reception focus area is read from the memory circuits 14A and 14B, and this data is switched as a switch control signal.
Added to 12,13. As a result, a desired delay time is determined, and an ultrasonic echo is received. Therefore, the interval between the reception focus areas in the portion shown in FIG. The interval becomes coarse. Note that the number of all reception focus areas is the same as the number of conventional reception focus areas shown in FIG.

As a result, a focused state can be obtained almost continuously from a shallow part to a deep part. As a result, the distance between the reception focus pattern areas can be coarse. The distance between the reception focus areas can be set finely in a close area where high resolution is required without deteriorating the image quality in a deep area. Optimum depth of field and improved image quality. At this time, since the number of reception focus areas does not increase, the number of reception delay time control data is smaller than when the same effect is obtained by finely setting the intervals of the reception focus areas over the entire visual field. And increase in hardware and the like can be suppressed, and the apparatus can be simplified.

Thereafter, the outputs of the respective channels are added to form a single reception echo, which is input to the receiver 6, envelope-detected, input to the DSC 7, scan-converted, and displayed as a B-mode image or an M-mode image showing the structure of the living body. 8 is output.

On the other hand, the received echo is also input to the Doppler detection unit 9, where a Doppler shift frequency proportional to a blood flow velocity generated by flowing blood in the living body is detected and analyzed, and a Doppler frequency spectrum, an average Doppler shift frequency, etc. Is obtained. These are input to the DSC 7, scan-converted, and output to the display unit 8 as Doppler images indicating blood flow information.

Also, for example, in FIG. 3 (2), similarly to FIG. 3 (1), if the control is performed at the depth selected by the control of the control circuit 16, that is, when the interval between the reception focus areas is set to be the finest, this control is performed. A good ultrasonic image can be obtained according to the region.

Further, for example, in FIG. 3 (3), if the control is performed at the depth selected by the control of the control circuit 16, that is, when the interval between the reception focus areas is set to be the finest,
A good ultrasonic image can be obtained according to this region.

Furthermore, if the reception focus area interval is finely set and controlled by the control circuit 16 in a shallow region as compared to a deep region, it is possible to appropriately focus on the diagnosis region.

The present invention is not limited to the embodiments described above. In the embodiment described above, two delay units A and B are used. However, if the configuration is such that, for example, switching noise does not matter, one system may be used. Further, the delay line is not limited to the LC delay line, but may be constituted by, for example, a digital circuit or the like. Further, in the above-described embodiment, the reception focus area is divided into four parts, but is not limited thereto, and may be divided into another number. Also, the order in which the intervals between the reception focus areas are roughened does not have to be roughened according to the depth. In addition, it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[Effects of the Invention] According to the present invention, it is possible to finely set the interval between the reception focus areas at the arbitrary depth without changing the number of the reception focus areas at the entire depth of field. The dynamic focus can be applied, a good ultrasonic image can be obtained, and the apparatus can be simplified without increasing the hardware. In addition, since the setting control can be performed so that the depth becomes wider as the depth of field becomes deeper, the receiving dynamic focus can be applied over a wide range from a shallow portion to a deep portion, and a good ultrasonic image can be obtained over a wide range. Is obtained. Furthermore, since the setting can be finely controlled in a shallow part compared to a deep part and the setting can be controlled at a selected depth, an ultrasonic diagnostic apparatus capable of appropriately focusing according to a diagnostic part and obtaining a good image can be obtained. Can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing an embodiment of an ultrasonic diagnostic apparatus according to the present invention, FIG. 2 is a connection diagram showing a specific configuration of a reception delay unit in the embodiment, and FIG. FIGS. 4 and 5 are diagrams for explaining an ultrasonic scan when a plurality of reception focuses are set, and FIG. 6 is a diagram showing a reception delay unit of the conventional device. FIG. 7 is a view showing a display example of an ultrasonic image obtained by a conventional example. DESCRIPTION OF SYMBOLS 1 ... Ultrasonic vibrator, 2 ... Pulser, 3 ... Transmission delay part, 4 ... Preamplifier, 5 ... Reception delay part, 6 ... Receiver, 7 ... DSC, 8 ... Display part, 9 ... ... Doppler detector, 10 ... Control circuit, 11, 12, 13 ... Changeover switch, 14A,
14B: memory circuit, 16: reception delay time control circuit, A
... A first delay unit, B... A second delay unit.

Claims (4)

(57) [Claims] An ultrasonic wave is transmitted to a living body, and biological information such as a signal reflected by a discontinuous surface in the living body is received by a reception delay unit while setting a plurality of reception focus areas in an ultrasonic beam direction by a reception delay unit. In the ultrasonic diagnostic apparatus that obtains ultrasonic diagnostic information of a living body by processing the same, the interval between the plurality of reception focus areas by the reception delay unit is finely set at an arbitrary depth, and the plurality of reception focus areas are set. An ultrasonic diagnostic apparatus, comprising: a control unit for controlling the number of images to be constant over the entire depth of field. 2. The ultrasonic diagnostic apparatus according to claim 1, further comprising control means for roughly setting and controlling the interval between the plurality of reception focus areas by the reception delay means as the depth of field increases. 3. An ultrasonic diagnostic apparatus according to claim 1, further comprising control means for finely setting and controlling the interval between the plurality of reception focus areas by the reception delay means in a shallow portion compared to a deep portion. . 4. The ultrasonic diagnostic apparatus according to claim 1, further comprising control means for finely controlling the interval between the plurality of reception focus areas by the reception delay means at a selected depth.