JP2008142130A - Ultrasonic diagnostic apparatus and its control processing program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To set frame rates of a plurality of different images respectively in an appropriate manner when a color flow mapping method is employed. <P>SOLUTION: An ultrasonic diagnostic apparatus 1 includes the following: a frame rate setting means 32 for setting each frame rate when a plurality of different image data is generated; a control signal generating part 33 for generating scan time phase control signals for controlling a time phase to scan with ultrasonic waves when the plurality of different image data are generated; a reference signal generating part 34 for generating reference signal to match the time phase of the plurality of different image data based on the scan time phase control signal; a DSC or digital scan converter 29 converts B-mode image data and color Doppler mode image data into a scan line signal array of a video format based on the reference signal supplied from the part 34; and a display part 14 for displaying by superimposing the B-mode image and the color Doppler mode image. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus and a control processing program therefor, and more particularly, an ultrasonic diagnostic apparatus and a control processing program therefor that can display a plurality of different images superimposed using a color flow mapping method. About.

  In recent years, a color flow mapping method (CFM) that can simultaneously display a B mode image based on B mode image data displayed in black and white and a Doppler mode image based on color displayed Doppler mode image data. ) Has been proposed.

  In the color flow mapping method, transmission / reception conditions such as the number of scanning lines per frame and the pulse repetition frequency, scanning density, and scanning range when transmitting / receiving ultrasonic waves are set in advance, and ultrasonic waves are set according to the set transmission / reception conditions. Are scanned and transmitted / received.

  That is, transmission / reception of ultrasonic waves for generating B-mode image data displayed in black and white and transmission / reception of ultrasonic waves for generating color-displayed Doppler mode image data are switched in units of vectors in a time division manner. Are executed in the order and number of times, image data of one frame is generated, and an image based on the image data is displayed.

  For example, as shown in FIG. 1, after ultrasonic transmission / reception a1, a2, and a3 for generating B-mode image data displayed in black and white are sequentially executed, Doppler mode image data displayed in color is generated. Ultrasonic transmission / reception b1, b2, b3, and b4 are sequentially executed, and thereafter ultrasonic transmission / reception for generating image data in both modes is alternately executed several times. Thereby, B-mode image data displayed in black and white and Doppler mode image data displayed in color for one frame are generated, and the B-mode image based on the B-mode image data displayed in black and white is displayed in color. A Doppler mode image based on the Doppler mode image data is superimposed and displayed.

  Thereafter, similar processing is repeated for each frame, and a B-mode image based on B-mode image data displayed in black and white and a Doppler mode image based on color-displayed Doppler mode image data can be superimposed and displayed in real time. It becomes possible.

  By the way, in the color flow mapping method, in addition to generating B-mode image data, Doppler mode image data is also generated. When generating Doppler mode image data, detect the Doppler signal that has undergone Doppler shift according to the speed of the moving reflector, and based on the detected Doppler signal, the direction, velocity, turbulence, etc. Therefore, it is necessary to detect the Doppler signal from the same sampling point at least twice or more.

  Therefore, when generating one frame of Doppler mode image data, more time is required than when generating one frame of B mode image data necessary for display using the color flow mapping method. It will take. In other words, the frame rate when generating Doppler mode image data for one frame is lower than the frame rate when generating B mode image data for one frame.

  Therefore, normally, in the color flow mapping method, as shown in FIG. 1, the transmission / reception of ultrasonic waves for generating Doppler mode image data is more than the transmission / reception of ultrasonic waves for generating B-mode image data. , The frame rate when generating Doppler mode image data for one frame and the frame rate when generating B mode image data for one frame are set in advance. The

  In addition, an ultrasonic diagnostic apparatus that can increase the frame rate when generating color Doppler mode image data in the color flow mapping method has been proposed (see, for example, Patent Document 1).

  According to the ultrasonic diagnostic apparatus proposed in Patent Document 1, scanning for one frame is repeated at a predetermined cycle while sequentially switching rasters for each transmission of ultrasonic waves, and a plurality of frames obtained by scanning are used. A two-dimensional distribution of blood flow information can be repeatedly generated with a predetermined period using the reflected signal of the minute.

This makes it possible to generate a two-dimensional distribution of blood flow information for one frame as compared to a conventional scan in which rasters are sequentially switched while repeating transmission a predetermined number of times (at least twice) for the same raster. The time required can be shortened. Therefore, it is possible to generate a two-dimensional distribution of blood flow information at a higher frame rate than the conventional scan.
JP-A-8-336534

  However, in the first place, in the color flow mapping method, in addition to ultrasound scanning for generating B-mode image data, ultrasound scanning for generating color Doppler mode image data with a low frame rate is performed. Compared with the case where B-mode image data is simply generated, it takes a lot of time and the overall frame rate becomes low. In the ultrasonic diagnostic apparatus proposed in Patent Document 1, the frame rate when generating color Doppler mode image data can be set to a high frame rate, but it is difficult to improve even the overall decrease in the frame rate. Met.

  Therefore, the rewriting speed for each frame of the B-mode image based on the displayed B-mode image data and the Doppler mode image based on the Doppler mode image data is still slow. There is a problem that it is inconvenient in diagnosing a specimen.

  In particular, the color Doppler mode image based on the color Doppler mode image data is used when observing the movement of blood flow in a desired region. Therefore, when the rewriting speed for each frame is slow, the operator It becomes impossible to accurately diagnose the movement of the flow.

  Further, in the ultrasonic diagnostic apparatus using the conventional color mapping method and the ultrasonic diagnostic apparatus proposed in Patent Document 1, the frame rate when generating B-frame image data for one frame and the Doppler for one frame are used. When the mode image data is generated, the frame rate is fixed to a fixed value in advance, and there is a problem that it is difficult to set an arbitrary frame rate according to the preference of the operator.

  The present invention has been made in view of such circumstances, and in the case of using the color flow mapping method, an ultrasonic diagnostic apparatus capable of suitably setting frame rates of different images and control processing thereof The purpose is to provide a program.

  In order to solve the above-described problem, the ultrasonic diagnostic apparatus of the present invention sets a frame rate when the first image data and the second image data are generated, and setting by the setting unit. Based on the respective frame rates when the first image data and the second image data are generated, the ultrasonic wave is scanned when the first image data and the second image data are generated. Control signal generating means for generating a control signal for controlling the time phase, reference signal generating means for generating a reference signal for matching the time phases of the first image data and the second image data based on the control signal, and a reference And a display unit configured to superimpose and display an image based on the first image data and an image based on the second image data based on the signal.

  The transmission means can transmit ultrasonic waves by vibrating a plurality of ultrasonic transducers according to the time phase of scanning ultrasonic waves controlled by the control signal.

  The ultrasonic diagnostic apparatus further includes data acquisition means for acquiring data relating to a predetermined frame rate when the first image data and the second image data are generated, and the setting means is acquired by the data acquisition means Frames when the first image data and the second image data are generated based on the data relating to a predetermined frame rate when the first image data and the second image data are generated, respectively. You can set the rate.

  The ultrasonic diagnostic apparatus further includes detection means for detecting an ECG signal from the subject, and the setting means, based on the ECG signal, sets the first image data and the first image data so as to match the heartbeat time phase of the subject. It is possible to set at least one frame rate when the second image data is generated.

  In order to solve the above-described problem, the control processing program of the ultrasonic diagnostic apparatus according to the present invention sets the respective frame rates when the first image data and the second image data are generated, When the first image data and the second image data are generated based on the respective frame rates when the first image data and the second image data set by the setting step process are generated. A control signal generating step for generating a control signal for controlling a time phase for scanning ultrasonic waves, and a reference for generating a reference signal for matching the time phases of the first image data and the second image data based on the control signal A signal generation step and a display step for superimposing and displaying an image based on the first image data and an image based on the second image data based on the reference signal are performed on a computer. Characterized in that to.

  In the ultrasonic diagnostic apparatus of the present invention, the respective frame rates when the first image data and the second image data are generated are set, and the set first image data and second image data are Based on the respective frame rates at the time of generation, a control signal for controlling the time phase for scanning the ultrasonic waves when the first image data and the second image data are generated is generated. Based on this, a reference signal that matches the time phases of the first image data and the second image data is generated, and an image based on the first image data and an image based on the second image data are superimposed based on the reference signal. Is displayed.

  In the control processing program of the ultrasonic diagnostic apparatus of the present invention, the respective frame rates when the first image data and the second image data are generated are set, and the set first image data and the second image data are set. Based on the respective frame rates at the time when the first image data and the second image data are generated, a control signal for controlling the time phase for scanning the ultrasonic waves is generated. A reference signal that matches the time phases of the first image data and the second image data is generated based on the control signal, and an image based on the first image data and an image based on the second image data are generated based on the reference signal. Are superimposed and displayed.

  According to the present invention, when the color flow mapping method is used, the frame rates of a plurality of different images can be suitably set.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 2 shows an internal configuration of the ultrasonic diagnostic apparatus 1 to which the present invention is applied.

  The ultrasonic diagnostic apparatus 1 includes a main body 11, an ultrasonic probe 12 connected to the main body 11 via an electric cable, an input unit 13, and a display unit 14.

  As shown in FIG. 2, the main body 11 of the ultrasonic diagnostic apparatus 1 includes a control unit 21, a transmission unit 22, a reception unit 23, an image data generation unit 24, a storage unit 25, a scan control circuit 26, and an ECG (Electrocardiogram) signal. A detection unit 27, an input data acquisition unit 28, and a DSC (Digital Scan Converter) 29 are configured.

  The control unit 21, the transmission unit 22, the reception unit 23, the image data generation unit 24, the storage unit 25, the scan control circuit 26, the ECG signal detection unit 27, the input data acquisition unit 28, and the DSC 29 are the ultrasonic diagnostic apparatus 1. Are connected to each other by a bus.

  The control unit 21 includes a CPU (Central Processing Unit) or MPU (Micro Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The CPU is a program or storage unit stored in the ROM. Various processes are executed in accordance with various application programs loaded from 25 into the RAM, and various control signals are generated and supplied to the respective units, whereby the drive of the ultrasonic diagnostic apparatus 1 is comprehensively controlled. The RAM appropriately stores data necessary for the CPU to execute various processes.

  The transmission unit 22 includes a rate pulse generator, a transmission delay circuit, and a pulsar (all not shown). The rate pulse generator is based on the control signal supplied from the scan control circuit 26 and the inside of the subject. A rate pulse for determining the pulse repetition frequency of the ultrasonic pulse incident on the signal is generated and supplied to the transmission delay circuit. The transmission delay circuit is a delay circuit for setting the focal position and deflection angle of the ultrasonic beam at the time of transmission. Based on the control signal supplied from the scan control circuit 26, the transmission delay circuit A delay time is added to the rate pulse supplied from the rate pulse generator so that the focal position and the deflection angle become a predetermined focal position and deflection angle, and the pulse is supplied to the pulser. Furthermore, the pulser is a drive circuit that generates a high-pressure pulse for driving the ultrasonic transducer, and generates a high-voltage pulse for driving the ultrasonic transducer based on the rate pulse supplied from the transmission delay circuit. Then, the generated high-pressure pulse is output to the ultrasonic probe 12.

  The transmission unit 22 can instantaneously change the delay time, the transmission frequency, the transmission drive voltage, and the like added to the rate pulse in accordance with an instruction from the scan control circuit 26. In particular, the transmission unit 22 is provided with, for example, a linear amplifier type transmission circuit or a circuit that can electrically switch a plurality of power supply units so that the transmission drive voltage can be changed instantaneously.

  The receiving unit 23 includes a preamplifier, an A / D converter, a reception delay circuit, an adder (all not shown), and the like, and the preamplifier reflects the ultrasonic pulse incident on the subject from the ultrasonic probe 12. A reception signal based on the wave is acquired, the acquired reception signal is amplified to a predetermined level, and the amplified reception signal is supplied to the A / D converter. The A / D converter converts the reception signal supplied from the preamplifier from an analog signal to a digital signal, and supplies it to the reception delay circuit.

  The reception delay circuit is based on the control signal supplied from the scan control circuit 26 and has a delay time (determined to determine the reception directivity for the reception signal after A / D conversion supplied from the A / D converter. (Delay time corresponding to the difference in propagation time of ultrasonic waves from the focus position of each ultrasonic transducer) is supplied to the adder. The adder adds reception signals from the ultrasonic transducers supplied from the reception delay circuit, and supplies the added reception signals to the image data generation unit 24 and the storage unit 25. Note that the reflection component from the direction corresponding to the reception directivity of the reception signal is enhanced by the addition of the adder.

  The image data generation unit 24 includes a B mode processing unit 30 and a Doppler mode processing unit 31. The B-mode processing unit 30 includes a logarithmic amplifier, an envelope detection circuit, and a TGC (Time Gain Control) circuit (all not shown), and the following processing is performed based on a control signal supplied from the control unit 21. I do.

  In other words, the logarithmic amplifier of the B-mode processing unit 30 logarithmically amplifies the reception signal supplied from the reception unit 23 and supplies the logarithmically amplified reception signal to the envelope detection circuit. The envelope detection circuit is a circuit for removing only the ultrasonic frequency component and detecting only the amplitude. The envelope detection circuit detects the envelope of the reception signal supplied from the logarithmic amplifier and supplies the detected reception signal to the TGC circuit. To do. The TGC circuit adjusts the intensity of the reception signal supplied from the envelope detection circuit so that the final luminance of the image becomes uniform, and supplies the adjusted B-mode image data to the storage unit 25. The B-mode image data stored in the storage unit 25 is supplied to the display unit 14 via the DSC 34, and then displayed as a B-mode image in which the intensity of the received signal is represented by luminance.

  The Doppler mode processing unit 31 includes a Doppler shift signal detector (not shown) that detects a Doppler shift signal from the received signal supplied from the receiving unit 23, and a Doppler shift signal detected by the Doppler shift signal detector. A spectrum Doppler mode processing unit (not shown) that analyzes the spectrum distribution of blood flow, and extracts blood flow information such as average blood flow velocity, variance, and power from the Doppler shift signal detected by the Doppler shift signal detector A color Doppler mode processing unit (not shown).

  The Doppler shift signal detection unit is composed of a reference signal generator, a π / 2 phase shifter, a mixer, an LPF (Low Pass Filter) (all not shown), and the like, and mainly receives signals received from the reception unit 23. Quadrature detection is performed, and the detected Doppler shift signal is supplied to the spectrum Doppler mode processing unit and the color Doppler mode processing unit.

  The spectrum Doppler mode processing unit includes an FFT (Fast Fourier Transform) analyzer and an arithmetic unit, and the FFT analyzer performs FFT analysis on the Doppler shift signal supplied from the Doppler shift signal processing unit. Calculates the center frequency, variance, and the like for the frequency spectrum from the FFT analyzer, and supplies the spectrum Doppler mode image data generated by the calculation to the storage unit 25. The spectrum Doppler mode image data stored in the storage unit 25 is supplied to the display unit 14 via the DSC 29, and then displayed as a spectrum Doppler mode image representing the distribution of the frequency spectrum included in the received signal.

  On the other hand, the color Doppler mode processing unit includes an MTI filter (Moving Target Indication Filter), an autocorrelator, an average speed calculator, a dispersion calculator, a power calculator (all not shown), and the like. An unnecessary fixed reflected wave is removed from a fixed reflector (for example, a blood vessel wall or a heart wall) from the Doppler shift signal supplied from the shift signal processing unit, and the Doppler bias from which the fixed reflected wave is removed. The shifted signal is supplied to the autocorrelator. The autocorrelator performs multi-point frequency analysis on the Doppler shift signal after removal of the fixed reflected wave supplied from the MTI filter in real time, and adds it to the average speed calculator, dispersion calculator, and power calculator. Supply.

  The average velocity calculator, the variance calculator, and the power calculator each calculate the average velocity, variance, and power of the blood flow, and supply the color Doppler mode image data generated by the calculation to the storage unit 25. The color Doppler mode image data stored in the storage unit 25 is supplied to the display unit 14 via the DSC 29, and then displayed as a color Doppler mode image representing blood flow information such as average blood flow velocity, dispersion, and power. Is done.

  Note that spectrum Doppler mode image data and color Doppler mode image data are collectively referred to as Doppler mode image data when there is no need to distinguish them individually.

  The storage unit 25 obtains raw data such as an output signal (RF signal) supplied from the receiving unit 23 and B mode supplied from the B mode processing unit 30 and the Doppler mode processing unit 31 of the image data generation unit 24. Image data and Doppler mode image data (spectrum Doppler mode image data and color Doppler mode image data) are acquired, and the acquired raw data, B mode image data, and Doppler mode image data are stored. The storage unit 25 supplies the stored raw data, B-mode image data, and Doppler mode image data to each unit as necessary.

  The storage unit 25 appropriately stores image data acquired via a network (not shown) and supplies it to each unit as necessary. The memory | storage part 25 memorize | stores various data suitably, and supplies it to each part as needed.

  The scan control circuit 26 is a circuit that controls various transmission / reception conditions when transmitting / receiving ultrasonic waves, and includes a frame rate setting unit 32, a control signal generation unit 33, and a reference signal generation unit 34. The frame rate setting unit 32 acquires and acquires data regarding each frame rate when generating the B-mode image data and the color Doppler mode image data supplied from the input data acquisition unit 28 according to the control of the control unit 21. Based on the data regarding the respective frame rates when generating the B-mode image data and the color Doppler mode image data, the respective frame rates for generating the B-mode image data and the color Doppler mode image data are set. Then, frame rate setting data, which is data relating to the set frame rate, is supplied to the storage unit 25 and the control signal generation unit 33.

  The control signal generation unit 33 acquires the frame rate setting data supplied from the frame rate setting unit 32 according to the control of the control unit 21, and reads and reads the scan control sequence stored in the storage unit 25. Based on the scan control sequence and the acquired frame rate setting data, a scan time phase control signal is generated to control the time phase for scanning ultrasound when B mode image data and color Doppler mode image data are generated. , And supplied to the transmitter 22 and the reference signal generator 34.

  In addition, the control signal generation unit 33 performs various transmission / reception conditions when transmitting / receiving ultrasonic waves set in advance (or input and acquired by the operator operating the input unit 13) according to the control of the control unit 21. Based on the data relating to the above, a transmission control signal and a reception control signal for controlling various transmission / reception conditions when transmitting / receiving ultrasound other than the time phase for scanning ultrasound are generated, and the transmission unit 22 and the reception unit 23, respectively. To supply.

  The reference signal generation unit 34 controls the B mode image data and the color Doppler mode image generated in the image data generation unit 24 based on the scan time phase control signal supplied from the control signal generation unit 33 according to the control of the control unit 21. A reference signal that matches the time phase of the data is generated, and the generated reference signal is supplied to the storage unit 25 and the DSC 29.

  Under the control of the control unit 21, the ECG signal detection unit 27 is attached to the body surface of the subject to detect an ECG signal, and an A / D that converts the ECG signal detected by the sensor from an analog signal to a digital signal. It comprises a converter and supplies the converted ECG signal to the storage unit 25. This ECG signal is stored in the storage unit 25 as supplementary information of the B-phase image data and Doppler mode image data of the same phase.

  The input data acquisition unit 28 acquires various data input by the operator operating the input unit 13, and appropriately supplies the acquired various data to each unit.

  The DSC 29 acquires the B-mode image data, the Doppler mode image data, the ECG signal, and the like supplied from the storage unit 25, and acquires the time phases based on the reference signal supplied from the reference signal generation unit 34. The B-mode image data, the Doppler mode image data, the ECG signal, and the like are converted from the scanning line signal sequence of the ultrasonic scan to the scanning line signal sequence of the video format, subjected to predetermined image processing and arithmetic processing, and the display unit 14 To supply.

  The ultrasonic probe 12 is connected to the main body 11 via an electric cable, and is an ultrasonic transducer that transmits and receives ultrasonic waves by bringing the front surface into contact with the surface of the subject, and is arranged in a one-dimensional array. Alternatively, it has micro ultrasonic transducers arranged in a two-dimensional matrix at the tip. This ultrasonic transducer is an electroacoustic transducer as a piezoelectric transducer. A matching layer for efficiently transmitting ultrasonic waves is provided in front of the ultrasonic transducer, and a packing material for preventing ultrasonic waves from propagating backward is provided behind the ultrasonic transducer.

  The ultrasonic probe 12 converts an electric pulse incident from the transmission unit 22 of the main body 11 into an ultrasonic pulse (transmission ultrasonic wave) at the time of transmission, and converts a reflected wave reflected by the subject into an electric signal at the time of reception. , Output to the main body 11. A part of the ultrasonic wave transmitted into the subject is reflected at the boundary surface or tissue between organs in the subject having different acoustic impedances. In addition, when the transmitted ultrasonic wave is reflected by a moving blood flow or a surface such as a heart wall, it undergoes a frequency shift due to the Doppler effect.

  The input unit 13 is connected to the main body 11 via an electric cable, and a display panel (not shown) for inputting various instructions of the operator on the operation panel, a trackball, various operation switches, various buttons, It has input devices such as a mouse and a keyboard, and is used by an operator to input various data such as patient information, measurement parameters, and physical parameters.

  The display unit 14 is connected to the DSC 29 of the main body 11 via a cable, and is provided with an LCD (Liquid Crystal Display) (not shown) and a CRT (Cathode Ray Tube) (not shown). The B-mode image data, the Doppler mode image data, the ECG signal, etc. from the DSC 29 converted from the video signal to the scanning line signal sequence of the video format are acquired, and the image based on the acquired B-mode image data and the image based on the Doppler mode image data Are displayed on an LCD or CRT (not shown), and an ECG signal is displayed on the LCD or CRT (not shown) as supplementary information.

  With reference to the flowchart of FIG. 3, the scan control process in the ultrasonic diagnostic apparatus 1 of FIG. 2 will be described.

  In this scan control process, the operator operates the input unit 13 (specifically, a dedicated switch such as a knob (not shown) for adjusting the frame rate provided in the input unit 13) to operate the B-mode image data and the color Doppler. It starts by inputting data relating to each frame rate when generating mode image data. Of course, a dedicated switch such as a knob for adjusting the frame rate provided in the input unit 13 can be installed in any place without being on the operation panel (not shown) of the input unit 13. It may be input based on a voice signal from the operator.

  In step S1, the input data acquisition unit 28 uses the color flow mapping method to generate B-mode image data and color Doppler mode image data input by the operator operating the input unit 13, respectively. Data relating to the rate is acquired, and data relating to the respective frame rates when generating the acquired B-mode image data and color Doppler mode image data is supplied to the scan control circuit 26.

  In step S2, the frame rate setting unit 32 of the scan control circuit 26 generates the B mode image data and the color Doppler mode image data supplied from the input data acquisition unit 28 according to the control of the control unit 21. When acquiring data relating to the frame rate and generating B-mode image data and color Doppler mode image data based on the data relating to the respective frame rates when generating the acquired B-mode image data and color Doppler mode image data Set each frame rate.

  The frame rate setting unit 32 supplies frame rate setting data related to the set frame rate to the storage unit 25 and the control signal generation unit 33.

  Specifically, the B-mode image data and the color Doppler mode image data are generated at a predetermined ratio (for example, 1: 4) when the B-mode image data and the color Doppler mode image data are generated. Set each frame rate when generating. In other words, since the color Doppler mode image based on the color Doppler mode image data is used when observing the movement of blood flow in a desired site, the frame rate when generating the color Doppler mode image data is higher. Set each frame rate to be higher.

  Accordingly, when color flow mapping is used according to the preference of the operator, the respective frame rates for generating the B-mode image data and the color Doppler mode image data can be suitably set.

  The storage unit 25 acquires the frame rate setting data supplied from the scan control circuit 26 and stores the acquired frame rate setting data.

  In step S3, the control signal generation unit 33 acquires the frame rate setting data supplied from the frame rate setting unit 32 according to the control of the control unit 21, and reads the scan control sequence stored in the storage unit 25. Scan time phase control for controlling the time phase for scanning ultrasound when B mode image data and color Doppler mode image data are generated based on the read scan control sequence and the acquired frame rate setting data A signal is generated and supplied to the transmitter 22 and the reference signal generator 34.

  That is, when the ratio of the respective frame rates when generating the B-mode image data and the color Doppler mode image data by the process of step S2 is set to 1: N, the B-mode image data for one frame is generated. After the ultrasonic transmission / reception A1 is executed, the time phase for scanning the ultrasonic waves is controlled so that ultrasonic transmission / reception B1 to BN for generating color Doppler mode image data for N frames is executed, Thereafter, the time phase for scanning the ultrasonic waves at the same ratio is controlled. Thereby, B-mode image data and color Doppler mode image data are generated at a ratio of 1 to N.

  Specifically, in the case of the example of FIG. 4, the ratio of the respective frame rates when generating the B mode image data and the color Doppler mode image data is set to 1: 5, and the B mode image for one frame is set. When ultrasonic transmission / reception A1 for generating data is executed, and ultrasonic transmission / reception B1 to B5 for generating color Doppler mode image data for five frames is executed, and then scanning is performed. The phase is controlled, and thereafter the time phase of scanning the ultrasonic wave at the same ratio is controlled. As a result, B-mode image data and color Doppler mode image data are generated at a ratio of 1: 5.

  Note that the time-phase scan control sequence for scanning the ultrasonic waves when the B-mode image data and the color Doppler mode image data are generated is not limited to such a case, and the other is based on the acquired frame rate setting data. The scan control sequence may be applied.

  For example, when the ratio of the respective frame rates when generating B-mode image data and color Doppler mode image data is set to 1: N, the conventional scan control sequence (see FIG. 1) is used for the first frame. The scan control sequence in which the two frame rates in generating the Doppler mode image data for one frame and the B mode image data are substantially the same, and then the color Doppler for N frames. The time phase for scanning the ultrasound may be controlled so that transmission / reception of the ultrasound for generating the mode image data is executed, and thereafter the time phase for scanning the ultrasound may be controlled similarly.

  Of course, according to the preference of the operator, the respective frame rates for generating the B-mode image data and the color Doppler mode image data are set, and a time-phase scan control sequence for scanning a preset ultrasonic wave is set. You may make it change into the desired scan control sequence in a plurality of other scan control sequences.

  In addition, the control signal generation unit 33 performs various transmission / reception conditions when transmitting / receiving ultrasonic waves set in advance (or input and acquired by the operator operating the input unit 13) according to the control of the control unit 21. A transmission control signal for controlling various transmission / reception conditions (for example, pulse repetition frequency, frequency of ultrasonic waves to be transmitted / received, etc.) when transmitting / receiving ultrasonic waves, other than the time phase for scanning ultrasonic waves, based on the data relating to A reception control signal is generated and supplied to the transmission unit 22 and the reception unit 23, respectively.

  In step S <b> 4, the reference signal generation unit 34 performs the B-mode image data generated in the image data generation unit 24 based on the scan time phase control signal supplied from the control signal generation unit 33 according to the control of the control unit 21. A reference signal that matches the time phase of the color Doppler mode image data is generated, and the generated reference signal is supplied to the storage unit 25 and the DSC 29.

  In step S5, the image data generation unit 24 generates different B-mode image data and color Doppler mode image data. Specifically, different B-mode image data and color Doppler mode image data are generated at a ratio of a predetermined frame rate as follows.

  For example, as shown in FIG. 4, the ratio of the respective frame rates when generating the B-mode image data and the color Doppler mode image data is set to 1: 5, and the ultrasonic wave for generating the B-mode image data is set. A case will be described in which transmission / reception and transmission / reception of ultrasonic waves for generating color Doppler mode image data are executed at a ratio of 1: 5.

  The transmission unit 22 transmits an ultrasonic beam for generating B-mode image data to the subject based on the scan time phase control signal and the transmission control signal supplied from the scan control circuit 26. That is, the rate pulse device of the transmission unit 22 controls the time phase when scanning the ultrasonic wave based on the scan time phase control signal supplied from the scan control circuit 26 and transmits the transmission supplied from the scan control circuit 26. Based on the control signal, a rate pulse is generated to determine that the pulse repetition frequency of the ultrasonic pulse incident on the inside of the subject becomes a predetermined pulse repetition frequency, and is supplied to the transmission delay circuit. Further, the transmission delay circuit is configured so that the focal position and deflection angle of the ultrasonic beam at the time of transmission become a predetermined focal position and deflection angle (θ1) based on the transmission control signal supplied from the scan control circuit 26. A delay time is added to the rate pulse supplied from the rate pulse generator and the pulse is supplied to the pulser. Further, the pulser generates a high-pressure pulse for driving the ultrasonic transducer based on the rate pulse supplied from the transmission delay circuit, and outputs the generated high-pressure pulse to the ultrasonic probe 12. The ultrasonic probe 12 converts the high-pressure pulse (electric pulse) input from the transmission unit 22 into an ultrasonic pulse, and transmits the converted ultrasonic pulse to the subject. A part of the ultrasonic wave transmitted into the subject is reflected at the boundary surface or tissue between organs in the subject having different acoustic impedances.

  The ultrasonic probe 12 converts the reflected wave reflected by the subject into an electric signal and outputs it to the main body 11. Based on the reception control signal supplied from the scan control circuit 26, the reception unit 23 amplifies the reception signal input from the ultrasonic probe 12, adds a predetermined delay time, and outputs the B of the image data generation unit 24. This is supplied to the mode processing unit 30. That is, the preamplifier of the reception unit 23 acquires a reception signal based on the reflected wave of the ultrasonic wave input to the subject from the ultrasonic probe 12, amplifies the acquired reception signal to a predetermined level, and receives the amplified reception signal. The signal is supplied to the A / D converter. The A / D converter converts the reception signal supplied from the preamplifier from an analog signal to a digital signal, and supplies it to the reception delay circuit.

  The reception delay circuit is based on the reception control signal supplied from the scan control circuit 26, and the delay time necessary for determining the reception directivity for the reception signal after A / D conversion supplied from the A / D converter. (Delay time corresponding to the difference in propagation time of ultrasonic waves from the focus position of each ultrasonic transducer) is given and supplied to the adder. The adder adds the reception signals from the ultrasonic transducers supplied from the reception delay circuit, and supplies the added reception signals to the B-mode processing unit 30.

  The B-mode processing unit 30 performs various processes on the reception signal supplied from the receiving unit 23, generates B-mode image data in the θ1 direction, and supplies the B-mode image data to the storage unit 25. The storage unit 25 acquires the B-mode image data in the θ1 direction supplied from the B-mode processing unit 30, and stores the acquired B-mode image data in the θ1 direction.

  Next, the ultrasound transmission / reception direction is sequentially updated by [Delta] [theta] while changing to [[theta] 1+ (N-1) [Delta] [theta]], and ultrasound transmission / reception is performed in the same procedure as above by scanning in the N direction. Scan in real time. At this time, the scan control circuit 26 switches the delay times of the transmission delay circuit and the reception delay circuit of the transmission unit 22 and the reception unit 23 according to the control signal in order corresponding to a predetermined ultrasonic transmission / reception direction, while [θ1 + Δθ ] To [θ1 + (N−1) Δθ] directions are generated.

  In addition, the storage unit 25 generates the generated B-mode image data in the [θ1 + Δθ] to [θ1 + (N−1) Δθ] directions together with the already stored B-mode image data in the θ1 direction. Based on the reference signal supplied from the reference signal generation unit 34, it is stored as two-dimensional B-mode image data so as to match the time phase of color Doppler mode image data to be described later.

  In this way, two-dimensional B-mode image data for one frame of a predetermined time phase can be generated and stored together with the time phase of the generated color Doppler mode image data.

  Next, based on the scan time phase control signal and the transmission control signal supplied from the scan control circuit 26, the transmission unit 22 transmits an ultrasonic beam for generating color Doppler mode image data to the subject.

  That is, the rate pulse device of the transmission unit 22 controls the time phase when scanning the ultrasonic wave based on the scan time phase control signal supplied from the scan control circuit 26 and transmits the transmission supplied from the scan control circuit 26. Based on the control signal, a rate pulse is generated to determine that the pulse repetition frequency of the ultrasonic pulse incident on the inside of the subject becomes a predetermined pulse repetition frequency, and is supplied to the transmission delay circuit. Further, the transmission delay circuit is configured so that the focal position and deflection angle of the ultrasonic beam at the time of transmission become a predetermined focal position and deflection angle (θ1) based on the transmission control signal supplied from the scan control circuit 26. A delay time is added to the rate pulse supplied from the rate pulse generator and the pulse is supplied to the pulser.

  Further, the pulser generates a high-pressure pulse for driving the ultrasonic transducer based on the rate pulse supplied from the transmission delay circuit, and outputs the generated high-pressure pulse to the ultrasonic probe 12. The ultrasonic probe 12 converts the high-pressure pulse (electric pulse) input from the transmission unit 22 into an ultrasonic pulse, and transmits the converted ultrasonic pulse to the subject. A part of the ultrasonic wave transmitted into the subject is reflected at the boundary surface or tissue between organs in the subject having different acoustic impedances.

  The ultrasonic probe 12 converts the reflected wave reflected by the subject into an electric signal and outputs it to the main body 11. Based on the reception control signal supplied from the scan control circuit 26, the reception unit 23 amplifies the reception signal input from the ultrasonic probe 12, adds a predetermined delay time, and outputs the B of the image data generation unit 24. This is supplied to the mode processing unit 30. That is, the preamplifier of the reception unit 23 acquires a reception signal based on the reflected wave of the ultrasonic wave input to the subject from the ultrasonic probe 12, amplifies the acquired reception signal to a predetermined level, and receives the amplified reception signal. The signal is supplied to the A / D converter. The A / D converter converts the reception signal supplied from the preamplifier from an analog signal to a digital signal, and supplies it to the reception delay circuit.

  The reception delay circuit is based on the reception control signal supplied from the scan control circuit 26, and the delay time necessary for determining the reception directivity for the reception signal after A / D conversion supplied from the A / D converter. (Delay time corresponding to the difference in propagation time of ultrasonic waves from the focus position of each ultrasonic transducer) is given and supplied to the adder. The adder adds reception signals from the ultrasonic transducers supplied from the reception delay circuit, and supplies the added reception signals to the Doppler mode processing unit 31.

  The Doppler shift signal processing unit of the Doppler mode processing unit 31 mainly performs quadrature phase detection on the received signal supplied from the receiving unit 23 and supplies the detected Doppler shift signal to the color Doppler mode processing unit. .

  The MTI filter of the color Doppler mode processing unit removes an unnecessary fixed reflected wave from the fixed reflector from the Doppler shifted signal supplied from the Doppler shifted signal processing unit, and the Doppler from which the fixed reflected wave is removed. The deviation signal is supplied to the autocorrelator. The autocorrelator performs multi-point frequency analysis on the Doppler shift signal after removal of the fixed reflected wave supplied from the MTI filter in real time, and adds it to the average speed calculator, dispersion calculator, and power calculator. Supply.

  The average velocity calculator, the variance calculator, and the power calculator respectively calculate the average velocity, variance, and power of the blood flow, and supply the color Doppler mode image data in the θ1 direction generated by the calculation to the storage unit 25. To do. The storage unit 25 acquires the color Doppler mode image data in the θ1 direction supplied from the color Doppler mode processing unit of the Doppler mode processing unit 31, and stores the acquired color Doppler mode image data in the θ1 direction.

  Next, the ultrasound transmission / reception direction is sequentially updated by [Delta] [theta] while changing to [[theta] 1+ (N-1) [Delta] [theta]], and ultrasound transmission / reception is performed in the same procedure as above by scanning in the N direction. Scan in real time. At this time, the scan control circuit 26 switches the delay times of the transmission delay circuit and the reception delay circuit of the transmission unit 22 and the reception unit 23 according to the control signal in order corresponding to a predetermined ultrasonic transmission / reception direction, while [θ1 + Δθ ] To [θ1 + (N−1) Δθ] direction color Doppler mode image data is generated.

  In addition, the storage unit 25 scans the generated color Doppler mode image data in the [θ1 + Δθ] to [θ1 + (N−1) Δθ] directions together with the already stored color Doppler mode image data in the θ1 direction. On the basis of the reference signals supplied from the 26 reference signal generation units 34, the data is stored as two-dimensional color Doppler mode image data so as to match the time phase of the already stored B mode image data.

  In this manner, two-dimensional color Doppler mode image data for one frame of a predetermined time phase can be generated and stored together with the time phase of the B mode image data.

  Subsequently, the same process is repeated four times thereafter to generate a total of five frames of two-dimensional color Doppler mode image data, which is stored together with the time phase of the already stored B mode image data.

  In collecting (generating and storing) B-mode image data and color Doppler mode image data, an operator manually scans using an ultrasonic probe 12 having a plurality of ultrasonic transducers arranged in a one-dimensional array. Alternatively, the scanning may be performed mechanically. Further, scanning may be performed using an ultrasonic probe 12 having a plurality of ultrasonic transducers arranged in a two-dimensional matrix, and the present invention can be applied to any scanning method.

  The DSC 29 reads out B-mode image data of a predetermined time phase and color Doppler mode image data in a color ROI (region of interest) stored in the storage unit 25 according to the control of the control unit 21 and a reference signal generation unit 34. Based on the reference signal supplied from, the B-mode image data of the predetermined time phase read out and the color Doppler mode image data in the color ROI (region of interest) are scanned to scan the ultrasonic scanning line so that the time phases match. The signal sequence is converted into a video format scanning line signal sequence, subjected to predetermined image processing and arithmetic processing, and supplied to the display unit 14.

  In step S6, the display unit 14 displays the B-mode image data from the DSC 29 and the color Doppler mode image data in the color ROI (region of interest) converted from the scanning line signal sequence of the ultrasonic scan into the scanning line signal sequence of the video format. The acquired tomographic image based on the acquired B-mode image data and the color Doppler mode image based on the color Doppler mode image data in the color ROI (region of interest) are superimposed and displayed on an LCD or CRT (not shown).

  FIG. 5 shows a display example of a tomographic image based on B-mode image data displayed on the display unit 14 and a tomographic image based on color Doppler mode image data in a color ROI (region of interest).

  In the case of the example of FIG. 5, a color Doppler mode image (color image) based on color Doppler mode image data in a color ROI (region of interest) is superimposed on a B mode image (monochrome image) based on B mode image data and displayed. At the same time, the image is displayed at the set frame rate.

  That is, the frame rate of the color Doppler mode image based on the color Doppler mode image data in the color ROI (region of interest) can be increased.

  In the ultrasonic diagnostic apparatus 1 shown in the embodiment of the present invention, in the color flow mapping method, the frame rate when generating B-mode image data and the frame rate when generating color Doppler mode image data are set as an operator. Can be suitably set according to the user's preference. Thereby, for example, the frame rate in generating color Doppler mode image data used when observing the movement of blood flow in a desired region (that is, a high frame rate is required) is set as the B mode image data. Can be set higher than the frame rate in the case of generating. Therefore, when the color flow mapping method is used, an image suitable for diagnosis of the subject can be displayed.

  When used in diagnosing the subject's heart, when setting each frame rate in the processing of step S2 in FIG. 3, the ECG signal stored in the storage unit 25 is read out, and the read ECG signal is read out. The frame rate for generating the B-mode image data may be synchronized with the heartbeat. Specifically, for example, the frame rate is set so that B-mode image data is generated every time the heart contracts, and color Doppler mode image data is generated every time the other heart expands. Also good. As a result, when the color flow mapping method is used, it is possible to display an image more suitable for diagnosis of the subject.

  In the ultrasonic diagnostic apparatus 1 shown in the embodiment of the present invention, the two-dimensional tomographic image is used. However, for example, the ultrasonic diagnostic apparatus 1 may be used for a three-dimensional tomographic image.

  The series of processes described in the embodiment of the present invention can be executed by hardware, but can also be executed by software.

  In the embodiment of the present invention, the steps of the flowchart show examples of processing that is performed in time series in the order described. However, even if they are not necessarily processed in time series, they are performed in parallel or individually. The process to be executed is also included.

The conceptual diagram explaining the scanning control method in the conventional color flow mapping method. 1 is a block diagram showing an internal configuration of an ultrasonic diagnostic apparatus according to the present invention. 3 is a flowchart for explaining scan control processing in the ultrasonic diagnostic apparatus in FIG. 2. The conceptual diagram explaining the scan control method in a color flow mapping method. The figure which shows the example of a display of the tomographic image based on the tomographic image based on the B mode image data displayed on the display part of FIG. 2, and the color Doppler mode image data.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic diagnostic apparatus 11 Main body 12 Ultrasonic probe 13 Input part 14 Display part 21 Control part 22 Transmission part 23 Reception part 24 Image data generation part 25 Storage part 26 Scan control circuit 27 ECG signal detection part 28 Input data acquisition part 29 DSC
30 B-mode image data 31 Doppler mode image data 32 Frame rate setting unit 33 Control signal generation unit 34 Reference signal generation unit

Claims (5)

A transmission unit that vibrates a plurality of ultrasonic transducers and transmits ultrasonic waves, and is converted by the ultrasonic transducer that receives a reflected wave reflected from a subject among the ultrasonic waves transmitted by the transmission unit. In an ultrasonic diagnostic apparatus comprising at least first image data and image data generation means for generating second image data based on the received signal,
Setting means for setting respective frame rates when the first image data and the second image data are generated;
The first image data and the second image data are generated based on respective frame rates when the first image data and the second image data set by the setting unit are generated. Control signal generating means for generating a control signal for controlling a time phase for scanning ultrasonic waves when
A reference signal generating means for generating a reference signal for matching the time phases of the first image data and the second image data based on the control signal;
An ultrasonic diagnostic apparatus comprising: a display unit configured to superimpose and display an image based on the first image data and an image based on the second image data based on the reference signal. 2. The ultrasonic diagnosis according to claim 1, wherein the transmission unit transmits ultrasonic waves by vibrating a plurality of ultrasonic transducers according to a time phase of scanning ultrasonic waves controlled by the control signal. apparatus. Data acquisition means for acquiring data relating to a predetermined frame rate when each of the first image data and the second image data is generated;
The setting means includes the first image data and the first image data based on data relating to a predetermined frame rate when the first image data and the second image data acquired by the data acquisition means are respectively generated. The ultrasonic diagnostic apparatus according to claim 1, wherein each frame rate when the second image data is generated is set. A detection means for detecting an ECG signal from the subject;
The setting means sets at least one frame rate when the first image data and the second image data are generated based on the ECG signal so as to match the heartbeat time phase of the subject. The ultrasonic diagnostic apparatus according to claim 1, wherein the ultrasonic diagnostic apparatus is set. A transmission unit that vibrates a plurality of ultrasonic transducers and transmits the ultrasonic waves, and is converted by the ultrasonic transducer that receives a reflected wave reflected from the subject among the ultrasonic waves transmitted by the transmission unit In a control processing program for an ultrasonic diagnostic apparatus comprising image data generation means for generating first image data and second image data based on a received signal,
A setting step for setting respective frame rates when the first image data and the second image data are generated;
Based on the respective frame rates when the first image data and the second image data set by the setting step are generated, the first image data and the second image data are A control signal generating step for generating a control signal for controlling a time phase of scanning ultrasonic waves when generated;
A reference signal generation step for generating a reference signal for matching the time phases of the first image data and the second image data based on the control signal;
An ultrasonic diagnostic apparatus characterized by causing a computer to execute a display step of superimposing and displaying an image based on the first image data and an image based on the second image data based on the reference signal. Control processing program.

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