JP5132620B2 - Ultrasonic diagnostic equipment - Google Patents

Description

  The present invention relates to an ultrasonic diagnostic apparatus that transmits and receives ultrasonic waves in a subject and obtains and displays an ultrasonic tomographic image or a blood flow image of the diagnostic region using an echo signal generated by a reflected wave from the diagnostic region. Focus detection accuracy is improved by setting the receive delay correction value switching interval to the optimal value by arbitrarily specifying and setting the receive delay correction value switching interval at the standard sound speed assumed in advance. In addition, the present invention relates to an ultrasonic diagnostic apparatus that can automatically achieve the improvement in focus accuracy.

  A conventional ultrasonic diagnostic apparatus of this type includes a probe that transmits and receives ultrasonic waves in a subject, and generates ultrasonic waves by driving the probe, and ultrasonic waves that process received echo signals. A transmission / reception unit, and a phasing addition unit that sets a value of a switching interval of a reception delay correction value based on a standard sound velocity of a subject assumed in advance and aligns a phase of a reception signal processed by the ultrasonic transmission / reception unit. Then, image data is generated using a signal from the phasing addition unit, and displayed as an ultrasonic tomographic image or a blood flow image on the image display unit.

  The switching interval of the reception delay correction value in the phasing adder is assumed to be an average standard sound speed (for example, 1538 m / s) of the medium (human body) in advance when designing the device. The interval value was set in the phasing adder. Then, the user of the apparatus observes the image with the focus accuracy displayed by the reception delay correction value switching interval based on the standard sound speed assumed and set in advance.

  However, in such a conventional ultrasonic diagnostic apparatus, an average standard sound speed of the medium is assumed in advance at the time of designing the apparatus, and the value of the reception delay correction value switching interval based on this standard sound speed is set in the phasing adder. Therefore, when the apparatus is used, it is not easy to change the assumed sound speed of the medium and set the value of the reception delay correction value switching interval. This is because it is very difficult for the user to recalculate the received wave delay correction value in accordance with the change in the medium sound speed and to set it again in the apparatus, and it is impossible in a short time. Therefore, when the medium sound speed assumed in advance is different from that of the actual subject, the image quality of an image obtained by deteriorating the focus is lowered.

Therefore, an object of the present invention is to provide an ultrasonic diagnostic apparatus that can converge focus adjustment on a subject medium that cannot be converged by automatic adjustment by manual setting by an operator .

In order to achieve the above object, an ultrasonic diagnostic apparatus according to the present invention is shown in the following (1) and (2) .
(1) A probe that transmits / receives ultrasonic waves in a subject, an ultrasonic transmission / reception unit that drives the probe to generate ultrasonic waves and processes a received reflected echo signal, and the ultrasonic transmission / reception A phasing adder for aligning the phase of the received signal processed by the unit and specifying a reception delay correction value switching interval for switching the received delay correction value, and an image display for displaying the signal from the phasing addition unit as an image an ultrasonic diagnostic apparatus having a section, and a focus determination unit that calculates a focus accuracy based on the interval of switching of the phasing reception delay correction value specified to the adder, thus calculating the focus determination unit tone switch the focus switching interval adjusting unit that adjusts to gradually converge the reception delay correction value switching interval from the focus accuracy, whether or not to perform the adjustment by the focus switching interval adjusting unit which is A stop instruction section, the value of the received wave delay correction value switching interval, further comprising a focus switching interval relative value display unit for relatively displaying to the value of reception delay correction value switching interval with standard sound speed Is.

(2) a probe that transmits and receives ultrasonic waves in a subject, an ultrasonic transmission and reception unit that drives the probe to generate ultrasonic waves and processes the received reflected echo signals, and the ultrasonic transmission and reception A phasing adder for aligning the phase of the received signal processed by the unit and specifying a reception delay correction value switching interval for switching the received delay correction value, and an image display for displaying the signal from the phasing addition unit as an image A control unit that controls the probe, the ultrasonic transmission / reception unit, the phasing addition unit, and the image display unit, and an input unit that receives control parameters for causing the control unit to function. and an ultrasonic diagnostic apparatus, a focus determination unit that calculates a focus accuracy based on the interval of switching of the phasing reception delay correction value specified to the adder, from the focus determination unit to thus calculated focus accuracy Received wave delay And a focus switching interval adjusting unit that adjusts to gradually converge the correction value switching interval, wherein the input unit, whether or not to perform the adjustment by the focus switching interval adjusting unit be one that switches,
A focus switching interval relative value display unit is further provided for displaying the value of the received wave delay correction value switching interval relative to the value of the received wave delay correction value switching interval at the assumed standard sound speed .

1 is a block diagram showing a first embodiment of an ultrasonic diagnostic apparatus according to the present invention. The block diagram which shows 2nd embodiment of the ultrasonic diagnosing device by this invention. The block diagram which shows 3rd embodiment of the ultrasonic diagnosing device by this invention. The figure explaining operation | movement of the focus switching space | interval memory | storage part and the focus switching space | interval instruction | indication part in the ultrasonic diagnosing device of 1st embodiment. Explanatory drawing which shows the display state by the focus switching space | interval relative value display part in the ultrasonic diagnosing device of 3rd embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a block diagram showing a first embodiment of an ultrasonic diagnostic apparatus according to the present invention. This ultrasonic diagnostic apparatus obtains and displays an ultrasonic tomographic image or blood flow image of a diagnostic part using an echo signal by a reflected wave from the diagnostic part by transmitting / receiving an ultrasonic wave in a subject. As shown in FIG. 4, the probe 1 includes an ultrasonic transmission / reception unit 2, a phasing addition unit 3, an image display unit 4, a control unit 5, and a keyboard 6, and a focus switching interval storage unit 7. And a focus switching interval instruction unit 8.

  The probe 1 mechanically or electronically performs beam scanning to transmit and receive ultrasonic waves in the subject. Although not shown, the probe 1 is a source of ultrasonic waves and from inside the living body. One or a plurality of transducers for receiving the reflected echo.

  The ultrasonic transmission / reception unit 2 drives the probe 1 to generate ultrasonic waves and processes the received reflected echo signal. It has a known transmission pulser and transmission delay circuit for forming an ultrasonic beam to be transmitted inward, and a reception amplifier for amplifying a reflected echo signal received by the transducer of the probe 1.

  The phasing addition unit 3 can specify the interval for switching the reception delay correction value while aligning the phase of the reception signal processed by the ultrasonic transmission / reception unit 2, and each reflected echo signal received from the ultrasonic transmission / reception unit 2 In addition to the function of aligning the phases by receiving dynamic focus on the assumption of a constant sound velocity medium, a receiving delay circuit that can instantaneously perform receiving focusing operation according to the switching interval by specifying the switching interval of the receiving delay correction value And a phasing addition circuit comprising an adder and the like. In this case, the phasing adder 3 is set with a received wave delay correction value calculated at a standard sound speed assumed in advance.

  The image display unit 4 stores a plurality of frames of the signal from the phasing addition unit 3 in time series, writes the stored data for each scanning line of the ultrasonic beam, generates image data, and outputs the image data to the image For example, a television monitor that converts the data into B-mode tomographic image data and displays the image data.

  The control unit 5 controls the operation of each of the above components, and has a central processing unit (CPU) therein, and stores various control data and control software. Furthermore, the keyboard 6 is used for inputting from the operator of the apparatus via the control unit 5 and has been conventionally used for inputting patient personal information and supplementary explanation items, switching the apparatus mode, and the like. is there.

  Here, in the present invention, a focus switching interval storage unit 7 is connected to the phasing addition unit 3, and a focus switching interval instruction unit 8 is connected to the focus switching interval storage unit 7. The focus switching interval storage unit 7 and the focus switching interval instruction unit 8 refer to the switching interval value of the reception delay correction value of the phasing addition unit 3 and arbitrarily set the reception delay correction value switching interval. Means for variably instructing and setting.

  The focus switching interval storage unit 7 stores the switching interval value of the reception delay correction value set in the phasing addition unit 3, and includes, for example, a RAM or the like, and is received by the phasing addition unit 3. While the value of the delay correction value switching interval is being used, the stored value of the received delay correction value switching interval can be held and referenced. In this case, for example, by preparing a plurality of optimal reception delay correction value switching interval values for each observation region or each physique of the subject, and selecting the observation region or physique of the subject, the optimal reception is possible. A value of the wave delay correction value switching interval may be obtained.

  The focus switching interval instructing unit 8 sets an arbitrary reception delay correction value switching interval in the focus switching interval storage unit 7, and includes, for example, an input knob and the like. The delay correction value switching interval can be increased or decreased. When the receive delay correction value switching interval is widened, the focus is adapted to the sound speed slower than the initially assumed medium sound speed. It becomes. Thus, the focus can be adjusted by changing the reception delay correction value switching interval. In addition, the input delay correction value switching interval may be expanded or shortened by an instruction from the keyboard 6 without being limited to the input knob provided separately.

  Next, operations of the focus switching interval storage unit 7 and the focus switching interval instruction unit 8 will be described with reference to FIG. First, in the phasing addition unit 3 shown in FIG. 1, a reception delay correction value (see FIG. 4 (a)) calculated at a standard sound speed assumed in advance is set, and the focus switching interval storage unit 7 is similarly set. The reception delay correction value switching interval (see FIG. 4B) calculated at the standard sound speed is stored. When a good focus can be obtained at the standard sound speed assumed when observing the human body, this is sufficient and no change is necessary. However, if a sufficiently good focus cannot be obtained at the assumed standard sound speed due to differences in the physique of the subject or the ultrasonic beam path to the observation site, the switching interval of the reception delay correction value is reset.

  The phasing adder 3 shown in FIG. 1 configures one ultrasonic beam while changing the focus one after another according to the time (observation depth) when the ultrasonic wave reflects the received delay correction value. When the sound speed of the medium (subject) is slower than the assumed standard sound speed as shown in FIG. 4 (c), the reception delay correction value switching interval is set in advance as shown in FIG. The interval is longer than the current value. That is, the focus switching interval instruction unit 8 inputs an instruction for changing to the reception delay correction value switching interval shown in FIG. 4 (d), and the received delay correction stored in the focus switching interval storage unit 7 is performed. Reset the value switching interval. Then, the state becomes the same as when the reception delay correction value is recalculated by changing the medium sound speed in a pseudo manner, and an image with improved focus accuracy is obtained. Note that the rewriting of the focus switching interval storage unit 7 can be completed in about one to several clocks in terms of a computer cycle, so that an image with improved focus accuracy can be obtained almost instantaneously.

  In the case of an ultrasonic diagnostic apparatus capable of performing adaptive image reproduction processing, if the adaptive image reproduction processing is performed after adjusting the focus switching interval, correction values due to the adaptive image are prevented from being dissipated. be able to.

  FIG. 2 is a block diagram showing a second embodiment of the ultrasonic diagnostic apparatus according to the present invention. This embodiment is configured by adding a focus determination unit 9, a focus switching interval automatic adjustment unit 10, and an automatic adjustment stop instruction unit 11 to the configuration shown in FIG. Then, the focus determination unit 9, the focus switching interval automatic adjustment unit 10, and the focus switching interval storage unit 7 described above evaluate the focus accuracy calculated by the switching interval of the reception delay correction value of the phasing addition unit 3. The reception delay correction value switching interval is automatically adjusted so as to gradually converge from the evaluation result, and a means for predicting and setting the reception delay correction value switching interval is configured.

  The focus determination unit 9 evaluates the focus accuracy calculated by the switching interval of the reception delay correction value of the phasing addition unit 3, calculates the state of the ultrasonic beam calculated by the phasing addition unit 3, The calculation result is output to the focus switching interval automatic adjustment unit 10. For example, when the focus of the image output from the phasing addition unit 3 is poor, the visualization data after phasing addition has few high frequency components, and when the focus is sharpest, it contains the most high frequency components. Use it to output the magnitude of the output value of the high-pass filter that selectively extracts the high-frequency component of the visualization data after phasing addition, or to obtain and output the power value within the high-pass interval, or within the same high-pass interval The sum of absolute values of is output.

  In another configuration, the maximum value of the correlation value can be output as it is by using the fact that the output value becomes the smallest when the correlation between adjacent beams is focused most sharply. Further, when the Doppler signal is measured, the maximum value of the Doppler signal can be output. In this way, the signal measurement system converges so that the Doppler signal is strongest. Any value may be output as long as it is correlated with the sharpness of the focus.

  Furthermore, in any case, if the processing area is limited, the amount of calculation can be reduced, so that convergence is accelerated. For example, generally, the center of the image is often the region of interest of the observer, and this region is the object of calculation. In addition, a region having Doppler sensitivity close to the center of the image, a region of interest indicated by the observer using the keyboard 6, or the like can be used as a calculation target.

  The focus switching interval automatic adjustment unit 10 automatically adjusts the reception delay correction value switching interval so as to gradually converge from the evaluation result by the focus determination unit 9, and predicts the value of the reception delay correction value switching interval. Thus, the prediction result is output to the focus switching interval storage unit 7. For example, if the focus determination unit 9 is selected to output the maximum value when the focus is sharpest, first, focus determination is performed for each focus switching interval that equally divides the variable range of the focus switching interval. Compare the output of part 9. A section including one point before and after the point indicating the maximum value is further equally divided, and the same processing is repeated. If it is driven to a place where it cannot be divided, the focus switching interval showing the maximum value at that time becomes the optimum value to be set in the focus switching interval storage unit 7. In addition, when selecting the one that outputs the minimum value when the focus determination unit 9 is focused most sharply, the value to be set is determined by repeating the above determination while searching for the minimum value. Found. As a result, the reception delay correction value switching interval can be automatically changed to an optimum value.

  The automatic adjustment stop instructing unit 11 allows the operator to select whether or not to automatically adjust the switching interval of the received wave delay correction value by the focus switching interval automatic adjusting unit 10, for example, an input switch Etc. This automatic adjustment stop instruction unit 11 is useful when the automatic adjustment does not go well and the image quality continues to change rapidly, or when the observer decides that the focus has converged and wants to fix the image quality. . It should be noted that the operator may select whether or not to perform automatic adjustment according to an instruction from the keyboard 6 without being limited to an input switch provided separately. The automatic adjustment stop instruction unit 11 is not necessarily provided.

  FIG. 3 is a block diagram showing a third embodiment of the ultrasonic diagnostic apparatus according to the present invention. In this embodiment, a focus switching interval relative value display unit 12 is added to the focus switching interval storage unit 7 in addition to the configuration shown in FIG. This focus switching interval relative value display unit 12 serves as a means for displaying the current reception delay correction value switching interval value relative to the assumed reception delay correction value switching interval at the standard sound speed. Thus, for example, it is displayed on a part of the screen of the image display unit 4 as a relative deviation from the value of the reception delay correction value switching interval at the assumed standard sound speed.

  Next, display by the focus switching interval relative value display unit 12 will be described with reference to FIG. FIG. 5 shows a state in which the focus switching interval relative value scale 14 is displayed on a part of the screen of the image display unit 4 that displays the ultrasonic image 13. This focus switching interval relative value scale 14 sets the value of the reception delay correction value switching interval based on the assumed standard sound speed to 0, plus when the sound speed is faster than this value, plus minus when the slower speed is adjusted. As shown, the display position of the pointer is displayed so as to be relatively changed in accordance with the value of the current reception delay correction value switching interval. In FIG. 5, the indicator hand 15 corresponding to the current reception delay correction value switching interval set by the focus switching interval automatic adjustment unit 10 is displayed slightly biased to the minus side.

  As shown in FIG. 5, the focus switching interval relative value scale 14 has the indicator needle 15 corresponding to the current reception delay correction value switching interval value set by the focus switching interval automatic adjustment unit 10, and the focus. When the indicator needle 16 corresponding to the current reception delay correction value switching interval value manually set in the switching interval instruction section 8 is displayed at the same time, the indicator needle 15 during automatic adjustment is manually set by referring to this scale display. The operation of quickly moving the indicator needle 16 becomes possible. Thereby, the focus adjustment in the medium that cannot be converged by the automatic adjustment by the focus switching interval automatic adjustment unit 10 can be converged by the manual setting by the focus switching interval instruction unit 8. In this way, while observing the ultrasonic image 13 displayed on the image display unit 4, it is possible to see how the received delay correction value switching interval is adjusted with respect to fluctuations in sound speed, and it is easy to understand how the adjustment has converged. it can.

  The scale display by the focus switching interval relative value display unit 12 is not limited to being displayed on a part of the screen of the image display unit 4, and may be displayed on a dedicated display. Further, FIG. 3 shows the case where it is applied to the ultrasonic diagnostic apparatus of the embodiment shown in FIG. 2, but the present invention is not limited to this, and can also be applied to the ultrasonic diagnostic apparatus of the embodiment shown in FIG. .

  1 Probe, 2 Ultrasonic transceiver, 3 Phase adder, 4 Image display unit, 5 Control unit, 6 Keyboard, 7 Focus switching interval storage unit, 8 Focus switching interval instruction unit, 9 Focus determination unit, 10 Focus Automatic switching interval adjustment unit, 11 Automatic adjustment stop instruction unit, 12 Focus switching interval relative value display unit, 14 Focus switching interval relative value scale, 15 and 16 indicator hands

Claims (2)

A probe that transmits and receives ultrasound within the subject;
An ultrasonic transmission / reception unit for driving the probe to generate ultrasonic waves and processing a received reflected echo signal;
A phasing addition unit for aligning the phase of the reception signal processed by the ultrasonic transmission / reception unit and designating a reception delay correction value switching interval for switching the reception delay correction value ;
An image display unit that displays a signal from the phasing addition unit as an image;
An ultrasonic diagnostic apparatus comprising:
A focus determination unit that calculates focus accuracy based on a switching interval of the received wave delay correction value specified in the phasing addition unit;
A focus switching interval adjusting unit that adjusts to gradually converge the reception delay correction value switching interval from the focus determination unit to thus computed focusing accuracy,
And an adjustment stop instructing unit that switches whether to perform adjustment by the focus switching interval adjustment unit,
The ultrasonic wave further comprising a focus switching interval relative value display unit for displaying the value of the receiving delay correction value switching interval relative to the value of the receiving delay correction value switching interval based on the standard sound velocity. Diagnostic device. A probe that transmits and receives ultrasound within the subject;
An ultrasonic transmission / reception unit for driving the probe to generate ultrasonic waves and processing a received reflected echo signal;
A phasing addition unit for aligning the phase of the reception signal processed by the ultrasonic transmission / reception unit and designating a reception delay correction value switching interval for switching the reception delay correction value ;
An image display unit that displays a signal from the phasing addition unit as an image;
Said probe, said ultrasonic transmitting and receiving unit, the phasing and adding unit, the control unit for controlling the picture display unit,
An input unit for inputting a control parameter for causing the control in the control unit to function; and
An ultrasonic diagnostic apparatus comprising:
A focus determination unit that calculates focus accuracy based on a switching interval of the received wave delay correction value specified in the phasing addition unit;
And a focus switching interval adjusting unit that adjusts to gradually converge the reception delay correction value switching interval from the focus determination unit to thus computed focusing accuracy,
Wherein the input unit, whether or not to perform the adjustment by the focus switching interval adjusting unit be one that switches,
A focus switching interval relative value display unit for displaying the value of the reception delay correction value switching interval relative to the value of the reception delay correction value switching interval at the assumed standard sound speed is further provided. Ultrasonic diagnostic equipment.

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