Ultrasound diagnostic device, method for controlling the ultrasound diagnostic device, and control program for the ultrasound diagnostic device

Abstract

To generate Doppler sounds with the low-frequency clutter eliminated, without making the process complex.SOLUTION: An ultrasonic diagnostic device according to one aspect of the present disclosure includes a transceiver unit that transmits and receives ultrasonic waves to obtain a received signal related to the ultrasonic echo, a detection unit that detects the received signal to generate a Doppler signal, a filtering unit that performs filter processing to cut or reduce the low-frequency components included in the Doppler signal, and generates a first filtered Doppler signal and a second filtered Doppler signal from the Doppler signal, an analysis unit that subjects the first filtered Doppler signal to frequency analysis to generate an image signal, and a generation unit that generates an audio signal based on the second filtered Doppler signal.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to an ultrasonic diagnostic apparatus, a control method for an ultrasonic diagnostic apparatus, and a control program for an ultrasonic diagnostic apparatus.

Background Art

[0002] Conventionally, an ultrasonic diagnostic apparatus having a Doppler mode, which is an image mode for measuring the blood flow velocity of a subject using the Doppler principle and displaying the velocity change of the blood flow in a spectral form based on the Doppler waveform thus obtained, is known. In such an ultrasonic diagnostic apparatus, as the Doppler mode, there are, for example, types such as a PWD (pulse wave Doppler) mode, a CWD (continuous wave Doppler) mode, and a TDI (tissue Doppler) mode. For example, in the PWD mode, an ultrasonic pulse is transmitted into the living body, and the Doppler information extracted from an observation region (Doppler sample gate) where a Doppler signal is measured, which is set at a specific depth, is frequency-analyzed, and a Doppler waveform is formed from the Doppler spectrum (representing the signal intensity for each blood flow velocity) thus obtained. Also, for example, in the CWD mode, continuous wave ultrasound is transmitted, and a reflected wave from the axis of the ultrasonic beam is received. Doppler information is extracted from the received signal thus obtained, and a Doppler waveform is formed in the same manner as above.

[0003] FIG. 1A is a diagram showing an example of a Doppler waveform.

[0004] The Doppler waveform is information on the temporal change in the velocity (i.e., the Doppler shift frequency) of the movement of an observation target generated based on a time-series Doppler spectrum. For example, as shown in FIG. 1A, the Doppler waveform is represented as a waveform with time on the horizontal axis, velocity (i.e., the Doppler shift frequency) on the vertical axis, and the signal intensity (also referred to as power) of each velocity (i.e., frequency component) as luminance (gray scale).

[0005] In Figure 1A, the circled area represents the Doppler sample gate, and the Doppler waveform is formed by capturing the blood flow signal in this area. In Figure 1A, the straight line on the time axis shown is called the baseline, the velocity above the baseline represents the velocity of blood flow approaching the probe, and the velocity below the baseline represents the velocity of blood flow moving away from the probe.

[0006] Incidentally, Doppler signals contain unwanted signals (called clutter, clutter signal, or clutter component) from slow-moving objects such as the walls of the heart. Since clutter interferes with the detection of weak blood flow signals, clutter, which is a strong, low-frequency unwanted signal, is usually removed by a wall motion filter, which is typically composed of a high-pass filter. Therefore, a wall motion filter can be considered a filter that cuts out the tissue component of the Doppler signal and extracts the blood flow component. Wall motion filters may also be called wall filters, clutter filters, or MTI (Moving Target Indicator) filters.

[0007] For example, Patent Document 1 discloses a technique for removing clutter. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 2-264644 [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] In the technology disclosed in Patent Document 1, to remove clutter, filtering (filtering) is performed by applying a bandpass filter (equivalent to a wall motion filter) common to both the image and the sound. The Doppler signal from which clutter has been removed by the bandpass filter is then frequency-analyzed to generate a spectral signal. Furthermore, in order to remove low-frequency clutter from the Doppler sound, the clutter is filtered in the spectral signal, and the filtered signal is then inversely transformed by Fourier to generate the Doppler sound. In this technology, since the Doppler sound is generated from the spectral signal in this way, a process of synthesizing the inverse Fourier transform result into the Doppler sound is required, making the process complex.

[0010] This disclosure has been made in view of the above-mentioned problems, and aims to provide an ultrasound diagnostic apparatus, a control method for the ultrasound diagnostic apparatus, and a control program for the ultrasound diagnostic apparatus that enable the generation of Doppler sound with low-frequency clutter removed without complicating the processing. [Means for solving the problem]

[0011] One aspect of this disclosure is, A transmitting and receiving unit that transmits and receives ultrasonic waves to obtain a received signal related to the ultrasonic echo, A detection unit that detects the received signal and generates a Doppler signal, Filtering is performed to cut or suppress low-frequency components included in the Doppler signal. It is a filtering processing unit. , The first filter The Doppler signal Apply to First filtered Doppler signal A second filter having different filter characteristics from the first filter is generated and applied to the Doppler signal. A filtering unit that generates a second filtered Doppler signal, The first filtered Doppler signal is frequency-analyzed spectrum An analysis unit that generates an image signal, A generation unit that generates an audio signal based on the second filtered Doppler signal, Equipped with 、 The analysis unit is connected to the filtering unit such that the second filtered Doppler signal is not input and only the first filtered Doppler signal is input. The generation unit is connected to the filtering unit such that the first filtered Doppler signal is not input, but the second filtered Doppler signal is input. superProvide an ultrasonic diagnostic apparatus. Other aspects of this disclosure are: A transmitting and receiving unit that transmits and receives ultrasonic waves to obtain a received signal related to the ultrasonic echo, <000007...... A filtering unit that performs filtering to cut or suppress low-frequency components contained in the Doppler signal, comprising: a filtering unit that applies a third filter to the Doppler signal to generate a first filtered Doppler signal; and a filtering unit that applies a fourth filter having different filter characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal; An analysis unit that performs frequency analysis on the first filtered Doppler signal to generate a spectral image signal, A generation unit that generates an audio signal based on the second filtered Doppler signal, Equipped with, The third and fourth filters are configured as high-pass filters. The gain change in the transition region of the fourth filter is more gradual than the gain change in the transition region of the third filter. We provide ultrasound diagnostic equipment. Other aspects of this disclosure are: A transmitting and receiving unit that transmits and receives ultrasonic waves to obtain a received signal related to the ultrasonic echo, A detection unit that detects the received signal and generates a Doppler signal, A filtering unit that performs filtering to cut or suppress low-frequency components contained in the Doppler signal, comprising: a filtering unit that applies a third filter to the Doppler signal to generate a first filtered Doppler signal; and a filtering unit that applies a fourth filter having different filter characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal; An analysis unit that performs frequency analysis on the first filtered Doppler signal to generate a spectral image signal, A generation unit that generates an audio signal based on the second filtered Doppler signal, ... Equipped with, The third and fourth filters are configured as high-pass filters. The gain in the cutoff region of the fourth filter is higher than the gain in the cutoff region of the third filter. We provide ultrasound diagnostic equipment.

[0012] Moreover, one aspect of the present disclosure is A step of transmitting and receiving ultrasonic waves to obtain a received signal related to an ultrasonic echo, A step of detecting the received signal to generate a Doppler signal, Performing a filtering process to cut or suppress low-frequency components included in the Doppler signal It is a step , The first filter The Doppler signal Apply to A first filtered Doppler signal A second filter having different filter characteristics from the first filter is generated and applied to the Doppler signal. A step of generating a second filtered Doppler signal, Performing frequency analysis on the first filtered Doppler signal to spectrum Generate an image signal, A step of generating an audio signal based on the second filtered Doppler signal, Including fruit, The step of generating the spectral image signal is performed using the first filtered Doppler signal without using the second filtered Doppler signal. The step of generating the sound signal uses the second filtered Doppler signal without using the first filtered Doppler signal. super This invention provides a control method for an acoustic diagnostic device. Other aspects of this disclosure are: The steps include transmitting and receiving ultrasound waves to obtain a received signal related to the ultrasound echo, The steps include: detecting the received signal and generating a Doppler signal; A step of performing a filtering process to cut or suppress low-frequency components contained in the Doppler signal, comprising: applying a third filter to the Doppler signal to generate a first filtered Doppler signal; and applying a fourth filter having different filtering characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal. The steps include: generating an image signal by frequency analysis of the first filtered Doppler signal; The steps include generating an audio signal based on the second filtered Doppler signal, Includes, The third and fourth filters are configured as high-pass filters. The gain change in the transition region of the fourth filter is more gradual than the gain change in the transition region of the third filter. This invention provides a method for controlling an ultrasound diagnostic device. Other aspects of this disclosure are: The steps include transmitting and receiving ultrasound waves to obtain a received signal related to the ultrasound echo, The steps include: detecting the received signal and generating a Doppler signal; A step of performing a filtering process to cut or suppress low-frequency components contained in the Doppler signal, comprising: applying a third filter to the Doppler signal to generate a first filtered Doppler signal; and applying a fourth filter having different filtering characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal. The steps include: generating an image signal by frequency analysis of the first filtered Doppler signal; The steps include generating an audio signal based on the second filtered Doppler signal, Includes, The third and fourth filters are configured as high-pass filters. The gain in the cutoff region of the fourth filter is higher than the gain in the cutoff region of the third filter. This invention provides a method for controlling an ultrasound diagnostic device.

[0013] Furthermore, one aspect of this disclosure is: Control method for any of the above ultrasound diagnostic devices This provides a control program for an ultrasound diagnostic device to cause the ultrasound diagnostic device to perform the following actions. [Effects of the Invention]

[0014] According to one aspect of this disclosure, since an audio signal can be generated without using an image signal (spectral signal) generated by frequency analysis, it is possible to generate Doppler sound with low-frequency clutter removed without complicating the processing. [Brief explanation of the drawing]

[0015] [Figure 1A] A diagram showing an example of a Doppler waveform. [Figure 1B] A diagram showing an example of a Doppler waveform. [Figure 1C] A diagram showing an example of a Doppler waveform. [Figure 2] A diagram showing an example of the appearance of an ultrasound diagnostic device according to the first embodiment of this disclosure. [Figure 3] This figure shows an example of the overall configuration of an ultrasound diagnostic apparatus according to the first embodiment of this disclosure. [Figure 4] This figure shows an example of the configuration of the Doppler signal processing unit of an ultrasound diagnostic apparatus according to the first embodiment of this disclosure. [Figure 5A] This figure shows examples of the filter characteristics of an image wall motion filter and an audio wall motion filter according to the first embodiment of this disclosure. [Figure 5B] This figure shows examples of the filter characteristics of an image wall motion filter and an audio wall motion filter according to the first embodiment of this disclosure. [Figure 6] A diagram illustrating an example of a user interface for cutoff frequency selection according to the first embodiment of this disclosure. [Figure 7] Flowchart showing an example of the operation of ultrasound diagnostic device A according to the first embodiment of this disclosure. [Figure 8] This figure shows an example of the configuration of the Doppler signal processing unit of an ultrasound diagnostic apparatus according to a second embodiment of this disclosure. [Figure 9A] This figure shows examples of the filter characteristics of a shared wall motion filter and a sound wall motion filter according to a second embodiment of this disclosure, and the filter characteristics obtained by combining these filters. [Figure 9B] This figure shows examples of the filter characteristics of a shared wall motion filter and a sound wall motion filter according to a second embodiment of this disclosure, and the filter characteristics obtained by combining these filters. [Figure 9C] This figure shows examples of the filter characteristics of a shared wall motion filter and a sound wall motion filter according to a second embodiment of this disclosure, and the filter characteristics obtained by combining these filters. [Figure 10] A diagram illustrating an example of a user interface for cutoff frequency selection according to a second embodiment of this disclosure. [Figure 11] Flowchart showing an example of the operation of ultrasound diagnostic device A according to the second embodiment of this disclosure. [Modes for carrying out the invention]

[0016] Preferred embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same function are denoted by the same reference numerals, and redundant descriptions will be omitted.

[0017] (First Embodiment) [Configuration of an ultrasound diagnostic device] The configuration of the ultrasound diagnostic apparatus according to the first embodiment of this disclosure (hereinafter referred to as "ultrasound diagnostic apparatus A") will be described below with reference to Figures 2 to 4.

[0018] Figure 2 shows an example of the external appearance of ultrasound diagnostic device A. Figure 3 shows an example of the overall configuration of ultrasound diagnostic device A.

[0019] Ultrasound diagnostic device A is used to visualize the shape, properties, or dynamics within a subject as an ultrasound image for diagnostic imaging. In this embodiment, blood flow within the blood vessels of a subject is used as an example of an object to be observed by ultrasound diagnostic device A. However, other tissues besides the blood flow of the subject may also be observed by ultrasound diagnostic device A.

[0020] As shown in Figure 2, ultrasound diagnostic device A comprises an ultrasound diagnostic device body 100 and an ultrasound probe 200.

[0021] The ultrasonic probe 200 transmits an ultrasonic beam (in this case, approximately 1 to 30 MHz) into a subject (e.g., the human body) and functions as an acoustic sensor that receives ultrasonic echoes reflected from the transmitted ultrasonic beam within the subject and converts them into electrical signals.

[0022] The user operates the ultrasound diagnostic device A by bringing the ultrasound beam transmitting and receiving surface of the ultrasound probe 200 into contact with the subject, and performs an ultrasound diagnosis. Any type of ultrasound probe, such as a convex probe, linear probe, sector probe, or three-dimensional probe, can be used for the ultrasound probe 200.

[0023] The ultrasound probe 200 is configured to include, for example, a plurality of transducers (e.g., piezoelectric elements) arranged in a matrix, and a channel switching unit (e.g., a multiplexer) for switching the on / off state of the plurality of transducers individually or in block units (hereinafter referred to as "channels"). Each transducer of the ultrasound probe 200 converts a voltage pulse generated by the ultrasound diagnostic device main unit 100 (transmitter 1a) into an ultrasound beam and transmits it into the subject, receives the ultrasound echo reflected within the subject, converts it into an electrical signal (hereinafter referred to as "received signal"), and outputs it to the ultrasound diagnostic device main unit 100 (receiver 1b).

[0024] The ultrasound diagnostic device main unit 100 includes a transmitting / receiving unit 1 (transmitting unit 1a, receiving unit 1b), a tomographic image generation unit 2, a Doppler signal processing unit 3, a display processing unit 4, a monitor 5, a Doppler sound output unit 6, a speaker 7, an operation input unit 8, and a control device 10.

[0025] The transmitting unit 1a of the transmitting / receiving unit 1 (the transmitting / receiving unit according to this disclosure) is a transmitter that sends voltage pulses, which are drive signals, to the ultrasonic probe 200. The transmitting unit 1a is composed of, for example, a high-frequency pulse oscillator, a pulse setting unit, etc. (none of which are shown). The transmitting unit 1a adjusts the voltage pulses generated by the high-frequency pulse oscillator to the voltage amplitude, pulse width, and transmission timing set by the pulse setting unit, and sends them out for each channel of the ultrasonic probe 200.

[0026] The transmitter 1a has a pulse setting unit for each of the multiple channels of the ultrasonic probe 200, allowing the voltage amplitude, pulse width, and transmission timing of the voltage pulse to be set for each of the multiple channels. For example, the transmitter 1a can change the target depth or generate different pulse waveforms by setting an appropriate delay time for multiple channels (for example, one pulse wave is transmitted in B mode, and four pulse waves are transmitted in PWD mode).

[0027] The receiving unit 1b of the transmitting / receiving unit 1 is a receiver that receives and processes the received signal related to the ultrasonic echo generated by the ultrasonic probe 200. The receiving unit 1b is composed of a preamplifier, an AD converter, a receiving beamformer, and a processing system switching unit (none of which are shown).

[0028] The receiver 1b uses a preamplifier to amplify the weak ultrasonic echo received signals for each channel, and the AD converter converts the received signals into digital signals. The receiver 1b then uses a receiving beamformer to combine the received signals from multiple channels into a single signal, which is then converted into acoustic line data. The receiver 1b also uses a processing system switching unit to control the destination of the received signals generated by the receiving beamformer, and outputs them to either the tomographic image generation unit 2 or the Doppler signal processing unit 3, depending on the operating mode being executed.

[0029] The tomographic image generation unit 2 acquires a received signal from the receiving unit 1b during B-mode operation and generates a tomographic image (also called a B-mode image) of the inside of the subject.

[0030] The tomographic image generation unit 2, for example, continuously stores the signal intensity of the ultrasound echo detected after the ultrasound probe 200 transmits a pulsed ultrasound beam in the depth direction in line memory over time. Then, as the ultrasound beam from the ultrasound probe 200 scans inside the subject, the tomographic image generation unit 2 sequentially stores the signal intensity of the ultrasound echo at each scanning position in line memory, generating two-dimensional data in frame units. The tomographic image generation unit 2 then generates a tomographic image by converting the signal intensity of the ultrasound echo detected at each position inside the subject into brightness values.

[0031] The tomographic image generation unit 2 is configured to include, for example, an envelope detection circuit, a dynamic filter, and a logarithmic compression circuit. The envelope detection circuit detects the signal strength by performing envelope detection on the received signal. The logarithmic compression circuit performs logarithmic compression on the signal strength of the received signal detected by the envelope detection circuit. The dynamic filter is a bandpass filter whose frequency characteristics are changed according to the depth, and it removes noise components contained in the received signal.

[0032] The Doppler signal processing unit 3 acquires the received signal from the receiver unit 1b in PWD mode, CWD mode, and TDI mode, and detects the Doppler deviation frequency relative to the transmission frequency of the ultrasound echo from the blood flow. The Doppler signal processing unit 3 then sequentially outputs information related to the Doppler spectrum, which represents the signal intensity for each Doppler deviation frequency (i.e., for each blood flow velocity), to the display processing unit 4. The blood flow velocity and the Doppler deviation frequency are directly proportional, as shown in equation (1) below. V = c / 2cosθ × Fd / F0 …(1) (However, V: blood flow velocity, F0: transmission frequency (or reception frequency) of the ultrasound beam, Fd: Doppler shift frequency, c: biosound velocity, θ: intersection angle between the beam direction of the ultrasound beam and the blood flow direction)

[0033] For example, in PWD mode operation, the Doppler signal processing unit 3 samples the received signal related to the ultrasonic echo in synchronization with the pulse repetition frequency when the ultrasonic probe 200 transmits pulsed ultrasonic beams at regular intervals according to the pulse repetition frequency. The Doppler signal processing unit 3 then detects the Doppler shift frequency based, for example, on the phase difference between the ultrasonic echo related to the nth ultrasonic beam and the (n+1)th ultrasonic beam from the same sample gate position.

[0034] Furthermore, the Doppler signal processing unit 3 separates the direction of the received signal from the receiving unit 1b relative to the ultrasound probe 200 (whether it is blood flow coming towards the ultrasound probe 200 or blood flow moving away from the ultrasound probe 200). The Doppler signal processing unit 3 converts the frequency components of the separated received signal to frequencies that produce an easily audible voice pitch, if necessary. Then, the Doppler signal processing unit 3 performs post-processing such as DA conversion on the separated and, if necessary, frequency-converted received signal to generate a Doppler sound signal, and outputs the generated Doppler sound signal to the Doppler sound output unit 6.

[0035] The Doppler signal processing unit 3 applies an image wall motion filter to the Doppler signal before generating the Doppler spectrum, and applies an audio wall motion filter to the Doppler signal before generating the Doppler audio signal. In this embodiment, by applying the image wall motion filter and the audio wall motion filter separately to the Doppler signal, the complexity of the process of generating Doppler audio by performing an inverse Fourier transform on the filtered signal is avoided, while generating Doppler audio with low-frequency clutter removed.

[0036] The display processing unit 4 acquires the tomographic image output from the tomographic image generation unit 2 and the Doppler spectrum output from the Doppler signal processing unit 3, and generates a display image to be shown on the monitor 5.

[0037] The display processing unit 4 includes a Doppler waveform generation unit 4a and a graphics processing unit 4b.

[0038] The Doppler waveform generation unit 4a generates a Doppler waveform based, for example, on a time-series Doppler spectrum sequentially output from the Doppler signal processing unit 3. As shown in Figure 1A, the Doppler waveform is information about the temporal change in the velocity of the movement of the object being observed (i.e., Doppler shift frequency) generated based on the time-series Doppler spectrum. For example, the blood flow velocity at each point in time is represented in the form of a single line, and the signal intensity for each blood flow velocity (i.e., each Doppler shift frequency) is represented by the brightness of the pixel.

[0039] The graphics processing unit 4b performs various image processing operations on the tomographic images output from the tomographic image generation unit 2 and the Doppler waveform images generated by the Doppler waveform generation unit 4a. Then, the graphics processing unit 4b generates a display image using these tomographic images and Doppler waveform images.

[0040] Monitor 5 is a display that shows display images generated by the display processing unit 4, and a user interface (screen) for settings that allows the user to set filter characteristics (e.g., cutoff frequency). Monitor 5 may be composed of, for example, a liquid crystal display.

[0041] The Doppler sound output unit 6 generates Doppler sound that is output from speaker 7 by power amplified by a power amplifier from the Doppler sound signal output from Doppler signal processing unit 3.

[0042] Speaker 7 is, for example, a speaker that outputs Doppler sound from Doppler sound output unit 6 to the outside.

[0043] Furthermore, the tomographic image generation unit 2, the Doppler signal processing unit 3, the display processing unit 4, and / or the Doppler sound output unit 6 are implemented by digital processing circuits, such as a DSP (Digital Signal Processor). However, these configurations can be modified in various ways; for example, some or all of them may be implemented by hardware circuits, or they may be implemented by calculation processing according to a program.

[0044] The operation input unit 8 is a user interface for the user to perform input operations, and consists of, for example, push-button switches, a keyboard, and a mouse. The operation input unit 8 converts the input operations performed by the user into operation signals and inputs them to the control device 10.

[0045] The control device 10 exchanges signals with the ultrasound probe 200, the transmitting / receiving unit 1, the tomographic image generation unit 2, the Doppler signal processing unit 3, the display processing unit 4, the monitor 5, the Doppler sound output unit 6, the speaker 7, and the operation input unit 8, and controls them comprehensively. The control device 10 is composed of components such as a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory). The functions of the control device 10 are realized by the CPU referencing control programs and various data stored in the ROM and RAM. However, some or all of the functions of the control device 10 are not limited to software processing, and can also be realized by dedicated hardware circuits or a combination thereof.

[0046] The control device 10 includes a transmit / receive control unit 11 and a filtering control unit 12.

[0047] The transmit / receive control unit 11 determines the transmission and reception conditions for the ultrasonic beam based on the type of connected ultrasonic probe 200 (e.g., convex type, sector type, or linear type), the depth of the object to be imaged within the subject, and the imaging mode (e.g., B-mode, PWD mode, color Doppler mode, or power Doppler mode), which are set by the user via the operation input unit 8. The transmit / receive control unit 11 then controls the transmit unit 1a and the receive unit 1b respectively to perform ultrasonic wave transmission and reception in the ultrasonic probe 200 in accordance with the transmission and reception conditions thus determined.

[0048] The filtering control unit 12 controls the wall motion filter and its filtering process based on the filter characteristics of the wall motion filter (for example, the image wall motion filter 3fi described later). The filter characteristics of the wall motion filter may be set and applied by the user via the operation input unit 8, or they may be applied based on the internal parameters of the ultrasound diagnostic device A.

[0049] Figure 4 shows an example of the configuration of the Doppler signal processing unit 3 that performs PWD according to the first embodiment. The Doppler signal processing unit 3 that performs PWD is configured to include, for example, a bandpass filter 3a, a quadrature detection unit 3b, a lowpass filter 3c, a range gate 3d, an integrating circuit 3e, a wall motion filter 3f, an FFT analysis unit 3g, and a Doppler sound signal generation unit 3h.

[0050] The bandpass filter 3a removes unnecessary frequency components from the received signal and outputs the received signal with the unnecessary frequency components removed to the quadrature detection unit 3b.

[0051] The quadrature detection unit 3b mixes the received signal output from the bandpass filter 3a with a reference signal in phase with the transmitted ultrasonic pulse and a reference signal with a phase difference of π / 2 from the transmitted ultrasonic pulse to generate a quadrature detection signal, which is output to the lowpass filter 3c. The quadrature detection unit 3b is an example of a detection unit according to the present disclosure. The quadrature detection signal is an example of a Doppler signal or Doppler shift signal according to the present disclosure.

[0052] The low-pass filter 3c removes the high-frequency components of the quadrature detection signal output from the quadrature detection unit 3b, generates a received signal related to the Doppler shift frequency, and outputs it to the range gate 3d.

[0053] The range gate 3d acquires only the ultrasonic echo from the Doppler sample gate depth from the received signal output from the low-pass filter 3c and outputs it to the integration circuit 3e.

[0054] The integration circuit 3e integrates the received signal output from the range gate 3d and outputs it to the wall motion filter 3f (the image wall motion filter 3fi and the sound wall motion filter 3fs, which will be described later).

[0055] The wall motion filter 3f applies the image wall motion filter 3fi and the sound wall motion filter 3fs to perform filtering to cut or suppress low-frequency components (clutter components) contained in the received signal output from the integrating circuit 3e. The wall motion filter 3f is an example of a filtering unit according to this disclosure.

[0056] The wall motion filter 3f includes an image wall motion filter 3fi and an audio wall motion filter 3fs.

[0057] The image wall motion filter 3fi may be configured, for example, as a high-pass filter. Under the control of the filtering control unit 12, the image wall motion filter 3fi performs filtering to cut or suppress low-frequency components (clutter components) contained in the received signal output from the integrating circuit 3e, based on the filter characteristics applied to the image (e.g., cutoff frequency, etc.). The image wall motion filter 3fi then generates a received signal with the clutter components cut or suppressed and outputs it to the FFT analysis unit 3g. This received signal with the clutter components cut or suppressed is an example of the first filtered Doppler signal or Doppler shift signal according to this disclosure.

[0058] The sound wall motion filter 3fs may be configured, for example, as a high-pass filter. Under the control of the filtering control unit 12, the sound wall motion filter 3fs performs filtering to cut or suppress low-frequency components (clutter components) contained in the received signal output from the integrating circuit 3e, based on the filter characteristics applied to sound (e.g., cutoff frequency, etc.). The sound wall motion filter 3fs then generates a received signal with the clutter components cut or suppressed and outputs it to the Doppler sound signal generation unit 3h. This received signal with the clutter components cut or suppressed is an example of the second filtered Doppler signal or Doppler shifted signal according to this disclosure.

[0059] Furthermore, the image wall motion filter 3fi and the sound wall motion filter 3fs may be implemented as separate filters or as a single filter, either as hardware or software modules. In the latter case, the filtering control unit 12 can implement the image wall motion filter 3fi and the sound wall motion filter 3fs by switching the filter characteristics of the single filter.

[0060] The FFT analysis unit 3g generates a Doppler spectrum by frequency analysis of the Doppler shift frequency component of the received signal output from the image wall motion filter 3fi, and outputs it to the display processing unit 4. The FFT analysis unit 3g is an example of an analysis unit according to this disclosure. The Doppler spectrum is an example of an image signal, spectral signal, or spectral image signal according to this disclosure.

[0061] The Doppler sound signal generation unit 3h separates the direction of the received signal output from the sound wall motion filter 3fs relative to the ultrasonic probe 200, performs frequency conversion as necessary, and generates a Doppler sound signal (for example, a stereo left signal and a stereo right signal) by performing post-processing such as DA conversion, and outputs it to the Doppler sound output unit 6. Note that the stereo left signal and the stereo right signal may be the same (i.e., monaural). The Doppler sound signal generation unit 3h is an example of a generation unit according to this disclosure. The Doppler sound signal is an example of a sound signal according to this disclosure.

[0062] [Filter characteristics of wall motion filters] First, before describing the filter characteristics of the wall motion filter according to this embodiment, we will explain an example of applying a wall motion filter common to both images and sound, referring to Figures 1B and 1C.

[0063] Figure 1B shows an example of a Doppler waveform, illustrating an instance where the tissue component of the Doppler signal cannot be completely filtered out by the wall motion filter. In Figure 1B, if there is a strong tissue signal (indicated by the arrow), this signal cannot be completely filtered out by the wall motion filter, resulting in a popping or sputtering noise mixed into the Doppler sound.

[0064] To avoid this (i.e., to cut out the low-frequency components), one possible solution is to increase the cutoff frequency of the wall motion filter to match the Doppler sound.

[0065] Figure 1C shows an example of a Doppler waveform, illustrating an example where the cutoff frequency of the wall motion filter is increased. When the cutoff frequency is increased in this way, a gap appears near the baseline of the image, as shown in Figure 1C.

[0066] The following describes examples of filter characteristics for the image wall motion filter 3fi and the sound wall motion filter 3fs that can avoid or suppress such problems, with reference to Figures 5A and 5B.

[0067] Figures 5A and 5B show examples of the filter characteristics of the image wall motion filter 3fi and the sound wall motion filter 3fs.

[0068] As shown in Figure 5A, the cutoff frequency of the sound wall motion filter 3fs (right side of Figure 5A) may be higher than the cutoff frequency of the image wall motion filter 3fi (left side of Figure 5A). This prevents or suppresses gaps near the baseline of the image while ensuring that no popping noises are mixed into the Doppler sound. The cutoff frequency may be defined, for example, as the frequency at which the filter's cutoff characteristic is -6dB.

[0069] Furthermore, as shown in Figure 5B, the filter characteristics may be such that the gain change in the transition region of the sound wall motion filter 3fs (right side of Figure 5B) is gentler than the gain change in the transition region of the image wall motion filter 3fi (left side of Figure 5B). This allows the bass to be retained while suppressing the sputtering noise, rather than completely cutting out the low frequencies of the Doppler sound. For example, by not completely cutting out the bass in the area enclosed by the dotted line frame in Figure 5B, the bass can be expressed, and by lowering the gain, the sputtering noise can be suppressed.

[0070] Furthermore, in the configuration shown in Figure 5B, a user interface may be provided that allows the user to select the cutoff frequency of the image wall motion filter 3fi. In addition, values ​​indicating the transition region and the steepness of the gain change in the transition region of the sound wall motion filter 3fs, which are associated with each cutoff frequency of the image wall motion filter 3fi, may be predetermined and stored in the ultrasound diagnostic device A.

[0071] [Wall Motion Filter Cutoff Frequency Selection] The following describes an example of a user interface (screen) for user-selection of the cutoff frequency, referring to Figure 6.

[0072] Figure 6 shows an example of a user interface that allows the user to select the cutoff frequency (i.e., the cutoff characteristic) of the wall motion filter. Such a user interface is displayed on the monitor 5 when the user operates the buttons on the operation input unit 8, keyboard, mouse, etc.

[0073] Figure 6(A) shows a user interface 601 including a setting area 602 for setting the cutoff frequency of the image wall motion filter 3fi, and a setting area 603 for setting the cutoff frequency of the sound wall motion filter 3fs. Setting area 602 is an example of a first setting unit according to this disclosure, and setting area 603 is an example of a second setting unit according to this disclosure.

[0074] The user can increase (or decrease) the index value (center in setting area 602) associated with the cutoff frequency of the image wall motion filter 3fi by, for example, hovering the mouse over the "+" button (or "-" button) in setting area 602 and clicking. Similarly, the user can increase (or decrease) the index value (center in setting area 603) associated with the cutoff frequency of the sound wall motion filter 3fs by, for example, hovering the mouse over the "+" button (or "-" button) in setting area 603 and clicking. Furthermore, the user can apply the setting by, for example, hovering the mouse over the button (not shown) for actually applying the cutoff frequency (to store the setting information in ultrasound diagnostic device A) and clicking. The same applies to the user interface described below.

[0075] The index values ​​shown may be integers from 1 to 10 for both images and sounds, and larger index values ​​may correspond to higher cutoff frequencies. Information indicating the correspondence between index values ​​and cutoff frequencies is stored in the ultrasound diagnostic device A. The same applies to the user interface described below.

[0076] In this example, the cutoff frequency of the image wall motion filter 3fi is the cutoff frequency associated with index value "2", and the cutoff frequency of the sound wall motion filter 3fs is the cutoff frequency associated with index value "8". Therefore, the cutoff frequency of the sound wall motion filter 3fs is higher than the cutoff frequency of the image wall motion filter 3fi.

[0077] Figure 6(B-1) shows a user interface 604 including a setting area 605 for setting the cutoff frequencies of the image wall motion filter 3fi and the sound wall motion filter 3fs using a single (common) setting item. In this example, a lower limit is set for the cutoff frequency of the sound wall motion filter 3fs, but this lower limit is an internal parameter that cannot be set by the user. The index value associated with the lower limit of the cutoff frequency is assumed to be 6. The setting area 605 is an example of the third setting unit according to this disclosure.

[0078] The user can increase (or decrease) the index value (center in setting area 605) associated with the cutoff frequency of the wall motion filter by, for example, hovering the mouse over the "+" button (or "-" button) in setting area 605 and clicking.

[0079] If the set cutoff frequency (index value) is greater than or equal to the lower limit, the set cutoff frequency will be applied to both the cutoff frequency of the image wall motion filter 3fi and the cutoff frequency of the sound wall motion filter 3fs.

[0080] On the other hand, if the set cutoff frequency falls below the lower limit, the set cutoff frequency will be applied to the image wall motion filter 3fi, but the lower limit of the cutoff frequency will be applied to the sound wall motion filter 3fs.

[0081] In this example, the cutoff frequency of the image wall motion filter 3fi is the cutoff frequency associated with index value "2". On the other hand, since the set index value "2" is smaller than the index value "6" which is associated with the lower limit of the cutoff frequency, the cutoff frequency of the sound wall motion filter 3fs is the cutoff frequency associated with index value "6". Therefore, the cutoff frequency of the sound wall motion filter 3fs is higher than the cutoff frequency of the image wall motion filter 3fi.

[0082] Therefore, in this example, the cutoff frequency of the sound wall motion filter 3fs will never be lower than the cutoff frequency of the image wall motion filter 3fi.

[0083] Figure 6(B-2) shows a user interface 606 that includes a setting area 607 similar to the setting area 605 in Figure 6(B-1), in addition to a setting area 608 for setting a lower limit of the cutoff frequency of the sound wall motion filter 3fs. Thus, in this example, this lower limit is settable by the user. Setting area 607 is an example of a third setting unit according to the present disclosure, and setting area 608 is an example of a fourth setting unit according to the present disclosure.

[0084] The user can increase (or decrease) the index value associated with the lower limit of the cutoff frequency of the sound wall motion filter 3fs by, for example, hovering the mouse over the "+" button (or "-" button) in setting area 608 and clicking.

[0085] If the set cutoff frequency (index value) is greater than or equal to the set lower limit (index value) of the cutoff frequency, the set cutoff frequency will be applied to both the cutoff frequency of the image wall motion filter 3fi and the cutoff frequency of the sound wall motion filter 3fs.

[0086] On the other hand, if the set cutoff frequency falls below the lower limit of the set cutoff frequency, the set cutoff frequency will be applied to the image wall motion filter 3fi, but the lower limit of the cutoff frequency will be applied to the sound wall motion filter 3fs.

[0087] In this example, the cutoff frequency of the image wall motion filter 3fi is the cutoff frequency associated with index value "8". On the other hand, since the set index value "8" is greater than the index value "6" which is associated with the lower limit of the cutoff frequency, the cutoff frequency of the sound wall motion filter 3fs is also the cutoff frequency associated with index value "8".

[0088] Therefore, even in this example, the cutoff frequency of the sound wall motion filter 3fs will never be lower than the cutoff frequency of the image wall motion filter 3fi.

[0089] [Operation of the ultrasound diagnostic device] The following describes an example of the operation of ultrasound diagnostic device A, with reference to Figure 7.

[0090] Figure 7 is a flowchart showing an example of the operation of the ultrasound diagnostic device A according to the first embodiment.

[0091] In step S701, the wall motion filter 3f determines the filter characteristics of the applied image wall motion filter 3fi and sound wall motion filter 3fs. The filter characteristics may be the cutoff frequency, the steepness (or gentleness) of the gain change in the transition region, etc., as described above.

[0092] In step S702, the transmitting / receiving unit 1 transmits and receives ultrasound waves using the ultrasound probe 200 to obtain a received signal relating to the ultrasound echo from the object being observed within the subject.

[0093] In step S703, the quadrature detection unit 3b detects the received signal and generates a Doppler signal.

[0094] In step S704, the wall motion filter 3f applies the image wall motion filter 3fi, which has the filter characteristics determined in step S701, to the Doppler signal to generate a first filtered Doppler signal. That is, the image wall motion filter 3fi generates a first filtered Doppler signal.

[0095] In step S705, the FFT analysis unit 3g performs frequency analysis on the first filtered Doppler signal to generate a Doppler spectrum.

[0096] In step S706, the wall motion filter 3f applies the sound wall motion filter 3fs, which has the filter characteristics determined in step S701, to the Doppler signal to generate a second filtered Doppler signal. That is, the sound wall motion filter 3fs generates a second filtered Doppler signal.

[0097] In step S707, the Doppler sound signal generation unit 3h generates a Doppler sound signal based on the second filtered Doppler signal.

[0098] Thereafter, the monitor 5 displays a display image generated by the display processing unit 4 based on the Doppler spectrum, and the speaker 7 outputs Doppler sound generated by the Doppler sound output unit 6 based on the Doppler sound signal.

[0099] Furthermore, the steps in the flowchart shown in Figure 7 are not limited to the order shown. For example, steps S704 and S706 may be executed in reverse order or in parallel.

[0100] [Effect] As described above, the ultrasound diagnostic apparatus (ultrasound diagnostic apparatus A) according to this embodiment is A transmitting / receiving unit (transmitting / receiving unit 1) transmits and receives ultrasonic waves to obtain a received signal related to the ultrasonic echo, The detection unit (Doppler signal processing unit 3, quadrature detection unit 3b) detects the received signal and generates a Doppler signal, A filtering unit (wall motion filter 3f, image wall motion filter 3fi, sound wall motion filter 3fs) performs filtering to cut or suppress low-frequency components contained in the Doppler signal and generates a first filtered Doppler signal and a second filtered Doppler signal from the Doppler signal, The analysis unit (FFT analysis unit 3g) generates an image signal (Doppler spectrum) by frequency analysis of the first filtered Doppler signal, A generation unit (Doppler sound signal generation unit 3h) that generates an audio signal (Doppler audio signal) based on the second filtered Doppler signal, It is equipped with.

[0101] According to the ultrasound diagnostic apparatus (ultrasound diagnostic apparatus A) of this embodiment, the generation unit (Doppler sound signal generation unit 3h) can generate a sound signal (Doppler sound signal) without using the image signal (Doppler spectrum) generated by frequency analysis by the analysis unit (FFT analysis unit 3g). Therefore, it is possible to generate Doppler sound with low-frequency clutter removed without complicating the processing.

[0102] (Second Embodiment) Next, a second embodiment of this disclosure will be described. The following describes the differences between the second embodiment and the first embodiment.

[0103] In this embodiment, the Doppler signal processing unit 3 applies a shared wall motion filter to the Doppler signal before generating the Doppler spectrum, and then applies a sound wall motion filter to the filtered Doppler signal obtained by applying the shared wall motion filter to the Doppler signal before generating the Doppler sound signal. By applying filters in this way, the complexity of generating Doppler sound by performing an inverse Fourier transform on the filtered signal is avoided, while generating Doppler sound with low-frequency clutter removed.

[0104] Figure 8 shows an example of the configuration of the Doppler signal processing unit 3 that performs PWD according to the second embodiment. The configuration of the wall motion filter 3f differs between the first and second embodiments. Specifically, the wall motion filter 3f according to the second embodiment has a common wall motion filter 3fc and an audio wall motion filter 3fs'. Therefore, in the second embodiment, the wall motion filter 3f applies the common wall motion filter 3fc and the audio wall motion filter 3fs' to perform filtering to cut or suppress low-frequency components (clutter components) included in the received signal output from the integrating circuit 3e.

[0105] The shared wall motion filter 3fc may be configured, for example, as a high-pass filter. Under the control of the filtering control unit 12, the shared wall motion filter 3fc performs filtering to cut or suppress low-frequency components (clutter components) contained in the received signal output from the integrating circuit 3e, based on the filter characteristics (e.g., cutoff frequency) applied to the shared (image) signal. The shared wall motion filter 3fc then generates a received signal with the clutter components cut or suppressed and outputs it to the FFT analysis unit 3g and the sound wall motion filter 3fs'. This received signal with the clutter components cut or suppressed is an example of the first filtered Doppler signal or Doppler shift signal according to this disclosure.

[0106] The sound wall motion filter 3fs' may be configured, for example, as a high-pass filter. Under the control of the filtering control unit 12, the sound wall motion filter 3fs' performs filtering to cut or suppress low-frequency components (clutter components) contained in the received signal output from the shared wall motion filter 3fc, based on the filter characteristics applied to sound (e.g., cutoff frequency, etc.). The sound wall motion filter 3fs' then generates a received signal with the clutter components cut or suppressed and outputs it to the Doppler sound signal generation unit 3h. The received signal with the clutter components cut or suppressed is an example of the second filtered Doppler signal or Doppler shifted signal according to this disclosure.

[0107] Furthermore, the shared wall motion filter 3fc and the sound wall motion filter 3fs' may be implemented as separate filters or as a single filter, either as hardware or software modules. In the latter case, the filtering control unit 12 can implement both the shared wall motion filter 3fc and the sound wall motion filter 3fs' by switching the filter characteristics of the single filter.

[0108] [Filter characteristics of wall motion filters] The following describes, with reference to Figures 9A to 9C, the filter characteristics of the shared wall motion filter 3fc and the sound wall motion filter 3fs', as well as examples of the filter characteristics obtained by combining these filters.

[0109] Figures 9A to 9C show examples of the filter characteristics of the shared wall motion filter 3fc and the sound wall motion filter 3fs', as well as the filter characteristics obtained by combining these filters.

[0110] As shown in Figure 9A, the cutoff frequency of the sound wall motion filter 3fs' (center of Figure 9A) may be higher than the cutoff frequency of the shared wall motion filter 3fc (left side of Figure 9A). As a result, the cutoff frequency of the sound wall motion filter 3fs' is applied to the sound (right side of Figure 9A). Therefore, it is possible to prevent or suppress gaps near the baseline of the image while preventing the Doppler sound from being mixed with popping noises. The cutoff frequency may be defined, for example, as the frequency at which the filter's cutoff characteristic is -6dB.

[0111] Furthermore, by keeping the cutoff frequency of the sound wall motion filter 3fs' fixed while changing the cutoff frequency of the shared wall motion filter 3fc, it is possible to achieve the same behavior as when a lower limit is set for the cutoff frequency of the sound wall motion filter 3fs as described above. That is, the cutoff frequency of the sound wall motion filter 3fs' can function like the lower limit of the cutoff frequency of the sound wall motion filter 3fs as described above. For example, as shown in Figure 9B, if the cutoff frequency of the shared wall motion filter 3fc (left side of Figure 9B) is higher than the cutoff frequency of the sound wall motion filter 3fs' (center of Figure 9B), the cutoff frequency of the shared wall motion filter 3fc will be applied to sound (right side of Figure 9B).

[0112] Alternatively, the filter characteristics of the sound wall motion filter 3fs' may be such that the gain change in the transition region is gentler than that of the shared wall motion filter 3fc. This allows for the preservation of low frequencies while suppressing the sputtering noise, rather than completely cutting out the low frequencies of the Doppler sound. Alternatively or additionally, the filter characteristics of the sound wall motion filter 3fs' may be such that the gain in the cutoff region is higher than that of the shared wall motion filter 3fc. This allows for a balance between suppressing the sputtering noise and preserving low frequencies by adjusting the gain in the cutoff region of the sound wall motion filter 3fs'. Figure 9C shows an example where both of these filter characteristics are applied. As shown in Figure 9C, if the gain change in the transition region of the sound wall motion filter 3fs' is gentler than the gain change in the transition region of the shared wall motion filter 3fc, and the gain in the cutoff region of the sound wall motion filter 3fs' is higher than the gain in the cutoff region of the shared wall motion filter 3fc (left and center of Figure 9C), then, for example, the low frequencies in the area enclosed by the dotted line frame (right side of Figure 9C) can be left without being completely cut.

[0113] Furthermore, in the configuration shown in Figure 9C, a user interface may be provided that allows the user to select the cutoff frequency of the shared wall motion filter 3fc and the cutoff range gain of the sound wall motion filter 3fs'. In addition, values ​​indicating the transition range of the sound wall motion filter 3fs and the steepness of the gain change in the transition range, which are associated with each combination of the cutoff frequency of the image wall motion filter 3fi and the cutoff range gain of the sound wall motion filter 3fs', may be predetermined and stored in the ultrasound diagnostic device A.

[0114] [Wall Motion Filter Cutoff Frequency Selection] The following describes an example of a user interface (screen) for user-selection of the cutoff frequency, with reference to Figure 10.

[0115] Figure 10 shows an example of a user interface that allows the user to select the cutoff frequency (i.e., the cutoff characteristic) of the wall motion filter. Such a user interface is displayed on the monitor 5 when the user operates the buttons on the operation input unit 8, keyboard, mouse, etc.

[0116] Figure 10(C) shows a user interface 1001 including a setting area 1002 for setting the cutoff frequency of the shared wall motion filter 3fc. In this example, the cutoff frequency of the sound wall motion filter 3fs' is an internal parameter that cannot be set by the user. The setting area 1002 is an example of the fifth setting unit according to this disclosure. Note that the operation of the user interface 1001 shown in Figure 10(C) is the same as the operation of the user interface 604 shown in Figure 6(B-1), so the explanation is omitted.

[0117] Figure 10(D) shows a user interface 1003 that includes a setting area 1004 similar to the setting area 1002 in Figure 10(C), as well as a setting area 1005 for setting the cutoff frequency of the sound wall motion filter 3fs'. In this example, the cutoff frequency of the sound wall motion filter 3fs' can be set by the user. Setting area 1004 is an example of the fifth setting unit according to this disclosure, and setting area 1005 is an example of the sixth setting unit according to this disclosure. Note that the operation of the user interface 1003 shown in Figure 10(D) is the same as the operation of the user interface 601 shown in Figure 6(A), so the explanation is omitted.

[0118] [Operation of the ultrasound diagnostic device] The following describes an example of the operation of ultrasound diagnostic device A, with reference to Figure 11.

[0119] Figure 11 is a flowchart showing an example of the operation of the ultrasound diagnostic device A according to the second embodiment.

[0120] In step S1101, the wall motion filter 3f determines the filter characteristics of the shared wall motion filter 3fc and the sound wall motion filter 3fs' to be applied. The filter characteristics may be the cutoff frequency, the steepness (or gentleness) of the gain change in the transition region, etc., as described above.

[0121] In step S1102, the transmitting / receiving unit 1 transmits and receives ultrasound waves using the ultrasound probe 200 to obtain a received signal relating to the ultrasound echo from the object being observed within the subject.

[0122] In step S1103, the quadrature detection unit 3b detects the received signal and generates a Doppler signal.

[0123] In step S1104, the wall motion filter 3f applies the shared wall motion filter 3fc, which has the filter characteristics determined in step S1101, to the Doppler signal to generate a first filtered Doppler signal. That is, the shared wall motion filter 3fc generates a first filtered Doppler signal.

[0124] In step S1105, the FFT analysis unit 3g performs frequency analysis on the first filtered Doppler signal to generate a Doppler spectrum.

[0125] In step S1106, the wall motion filter 3f applies the sound wall motion filter 3fs' having the filter characteristics determined in step S1101 to the first filtered Doppler signal to generate a second filtered Doppler signal. That is, the sound wall motion filter 3fs' generates a second filtered Doppler signal.

[0126] In step S1107, the Doppler sound signal generation unit 3h generates a Doppler sound signal based on the second filtered Doppler signal.

[0127] Thereafter, the monitor 5 displays a display image generated by the display processing unit 4 based on the Doppler spectrum, and the speaker 7 outputs Doppler sound generated by the Doppler sound output unit 6 based on the Doppler sound signal.

[0128] [effect] As described above, the ultrasound diagnostic apparatus (ultrasound diagnostic apparatus A) according to this embodiment is A transmitting / receiving unit (transmitting / receiving unit 1) transmits and receives ultrasonic waves to obtain a received signal related to the ultrasonic echo, The detection unit (Doppler signal processing unit 3, quadrature detection unit 3b) detects the received signal and generates a Doppler signal, A filtering unit (wall motion filter 3f, shared wall motion filter 3fc, sound wall motion filter 3fs') performs filtering to cut or suppress low-frequency components contained in the Doppler signal and generates a first filtered Doppler signal and a second filtered Doppler signal from the Doppler signal, The analysis unit (FFT analysis unit 3g) generates an image signal by frequency analysis of the first filtered Doppler signal, A generation unit (Doppler sound signal generation unit 3h) that generates an audio signal based on the second filtered Doppler signal, It is equipped with.

[0129] According to the ultrasound diagnostic apparatus (ultrasound diagnostic apparatus A) of this embodiment, the generation unit (Doppler sound signal generation unit 3h) can generate a sound signal (Doppler sound signal) without using the image signal (Doppler spectrum) generated by frequency analysis by the analysis unit (FFT analysis unit 3g). Therefore, it is possible to generate Doppler sound with low-frequency clutter removed without complicating the processing.

[0130] (Variation 1) In the user interface 601 described above, the user can set the cutoff frequency of the image wall motion filter 3fi to be higher than the cutoff frequency of the sound wall motion filter 3fs. Similarly, in the user interface 1001 described above, the user can set the cutoff frequency of the shared wall motion filter 3fc to be higher than the cutoff frequency of the sound wall motion filter 3fs'. However, as with other user interface examples, the cutoff frequency of the sound wall motion filter 3fs (or sound wall motion filter 3fs') may not be lower than the cutoff frequency of the image wall motion filter 3fi (or shared wall motion filter 3fc). For example, if the cutoff frequency (index value) of the image wall motion filter 3fi is higher (larger) than the cutoff frequency (index value) of the sound wall motion filter 3fs, when the user clicks the button to actually apply the cutoff frequency, the ultrasound diagnostic device A may display a pop-up message on monitor 5 indicating that the setting cannot be applied.

[0131] (Modification 2) In the user interface 601 described above, the user selected the cutoff frequency by selecting an index value. However, instead of an index value, multiple cutoff frequencies could be displayed as options, allowing the user to select one of them. Alternatively, instead of an index value, the user could input the cutoff frequency itself.

[0132] (Variation 3) In the example shown in Figure 5B, the transition region of the sound wall motion filter 3fs and the value indicating the steepness of the gain change in the transition region were predetermined and stored in the ultrasound diagnostic device A. However, the values ​​indicating the transition region and the steepness of the gain change in the transition region may be displayed as options, allowing the user to select one of several options. Alternatively, the user may be able to input the values ​​indicating the transition region and the steepness of the gain change in the transition region themselves.

[0133] (Summary of the embodiments) An ultrasonic diagnostic apparatus according to one aspect of the present disclosure includes: a transmitting and receiving unit that transmits and receives ultrasonic waves to obtain a received signal relating to an ultrasonic echo; a detection unit that detects the received signal to generate a Doppler signal; a filtering unit that performs filtering to cut or suppress low-frequency components contained in the Doppler signal and generates a first filtered Doppler signal and a second filtered Doppler signal from the Doppler signal; an analysis unit that performs frequency analysis on the first filtered Doppler signal to generate an image signal; and a generation unit that generates an audio signal based on the second filtered Doppler signal.

[0134] With the above configuration, it is possible to generate sound signals without using image signals generated by frequency analysis, making it possible to generate Doppler sound with low-frequency clutter removed without complicating the processing.

[0135] In this ultrasound diagnostic apparatus, the filtering unit applies a first filter to the Doppler signal to generate a first filtered Doppler signal, and applies a second filter having different filter characteristics from the first filter to the Doppler signal to generate a second filtered Doppler signal.

[0136] With the above configuration, it is possible to apply filters with filter characteristics tailored to the spectral image and Doppler sound, respectively.

[0137] In this ultrasound diagnostic apparatus, the first filter and the second filter are configured as high-pass filters, and the cutoff frequency of the second filter is higher than the cutoff frequency of the first filter.

[0138] With the above configuration, it is possible to avoid cutting out signals near the baseline in the spectral image, and to cut out low-frequency components in the Doppler sound, thereby preventing the inclusion of sputtering noises.

[0139] In this ultrasound diagnostic apparatus, the first filter and the second filter are configured as high-pass filters, and the gain change in the transition region of the second filter is more gradual than the gain change in the transition region of the first filter.

[0140] With the above configuration, it is possible to retain the lower frequencies without completely cutting them out, thereby allowing the bass to be expressed, while suppressing crackling noises by lowering the bass gain.

[0141] This ultrasound diagnostic device further includes a user-operable first setting unit for setting the filter characteristics of the first filter, and a user-operable second setting unit for setting the filter characteristics of the second filter.

[0142] With the above configuration, users can adjust the filter characteristics to match both the spectral image and the Doppler sound.

[0143] In this ultrasound diagnostic apparatus, the filter characteristics of the first filter and the filter characteristics of the second filter are the cutoff frequencies.

[0144] With the above configuration, users can adjust the cutoff frequency to match both the spectral image and the Doppler sound, respectively.

[0145] The ultrasound diagnostic apparatus further includes a user-operable third setting unit for setting the cutoff frequencies of the first and second filters, wherein the cutoff frequency of the second filter is set to a lower limit, and if the set cutoff frequency of the second filter falls below the lower limit, the filtering unit applies the second filter having the lower limit cutoff frequency to generate the second filtered Doppler signal.

[0146] With the above configuration, the user can apply the cutoff frequencies of two filters with the simple operation of setting one cutoff frequency.

[0147] This ultrasound diagnostic device further includes a user-operable fourth setting unit for setting the lower limit.

[0148] With the above configuration, users can set the low-frequency range they want to cut out in Doppler tones.

[0149] In this ultrasound diagnostic apparatus, the filtering unit applies a third filter to the Doppler signal to generate a first filtered Doppler signal, and applies a fourth filter having different filter characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal.

[0150] With the above configuration, it is possible to apply filters with filter characteristics tailored to the spectral image and Doppler sound, respectively.

[0151] In this ultrasound diagnostic apparatus, the third filter and the fourth filter are configured as high-pass filters, and the cutoff frequency of the fourth filter is higher than the cutoff frequency of the third filter.

[0152] With the above configuration, it is possible to avoid cutting out signals near the baseline in the spectral image, and to cut out low-frequency components in the Doppler sound, thereby preventing the inclusion of sputtering noises.

[0153] In this ultrasound diagnostic apparatus, the third filter and the fourth filter are configured as high-pass filters, and the gain change in the transition region of the fourth filter is more gradual than the gain change in the transition region of the third filter.

[0154] With the above configuration, it is possible to retain the lower frequencies without completely cutting them out, thereby allowing the bass to be expressed, while suppressing crackling noises by lowering the bass gain.

[0155] In this ultrasound diagnostic apparatus, the third filter and the fourth filter are configured as high-pass filters, and the gain of the cutoff region of the fourth filter is higher than the gain of the cutoff region of the third filter.

[0156] With the above configuration, it is possible to strike a balance between suppressing crackling noises and preserving bass frequencies by adjusting the gain of the cutoff band of the fourth filter.

[0157] This ultrasound diagnostic device further includes a user-operable fifth setting unit for setting the filter characteristics of the third filter, and a user-operable sixth setting unit for setting the filter characteristics of the fourth filter.

[0158] With the above configuration, users can adjust the filter characteristics to match both the spectral image and the Doppler sound.

[0159] In this ultrasound diagnostic apparatus, the filter characteristics of the third filter and the filter characteristics of the fourth filter are the cutoff frequencies.

[0160] With the above configuration, users can adjust the cutoff frequency to match both the spectral image and the Doppler sound, respectively.

[0161] A control method for an ultrasound diagnostic apparatus according to one aspect of the present disclosure includes the steps of: transmitting and receiving ultrasound waves to obtain a received signal relating to an ultrasound echo; detecting the received signal to generate a Doppler signal; performing a filter process to cut or suppress low-frequency components contained in the Doppler signal to generate a first filtered Doppler signal and a second filtered Doppler signal from the Doppler signal; frequency analyzing the first filtered Doppler signal to generate an image signal; and generating an audio signal based on the second filtered Doppler signal.

[0162] With the above configuration, it is possible to generate sound signals without using image signals generated by frequency analysis, making it possible to generate Doppler sound with low-frequency clutter removed without complicating the processing.

[0163] A control program for an ultrasound diagnostic apparatus according to one aspect of the present disclosure causes the ultrasound diagnostic apparatus to perform the following steps: transmitting and receiving ultrasound waves to obtain a received signal relating to an ultrasound echo; detecting the received signal to generate a Doppler signal; performing a filter process to cut or suppress low-frequency components contained in the Doppler signal to generate a first filtered Doppler signal and a second filtered Doppler signal from the Doppler signal; frequency analyzing the first filtered Doppler signal to generate an image signal; and generating a sound signal based on the second filtered Doppler signal.

[0164] With the above configuration, it is possible to generate sound signals without using image signals generated by frequency analysis, making it possible to generate Doppler sound with low-frequency clutter removed without complicating the processing.

[0165] Although specific examples of the present invention have been described in detail above, these are merely illustrative and do not limit the scope of the claims. The technologies described in the claims include various modifications and changes to the specific examples illustrated above. [Industrial applicability]

[0166] One aspect of this disclosure is useful as an ultrasound diagnostic device capable of generating Doppler sound with low-frequency clutter removed without complicating the processing. [Explanation of symbols]

[0167] A Ultrasound diagnostic device 100 Ultrasound diagnostic equipment main unit 1 Transmitter / Receiver Unit 2. Tomographic Image Generation Unit 3. Doppler signal processing unit 3a Bandpass filter 3b. Quadrature detection section 3c low-pass filter 3D Range Gate 3e integral circuit 3f Wall Motion Filter 3fi Wall Motion Filter for Images 3fs Wall Motion Filter for Sound 3fc Shared Wall Motion Filter 3fs' Wall Motion Filter for Sound 3g FFT analysis section 3h Doppler sound signal generation unit 4 Display Processing Unit 4a Doppler waveform generation unit 4b Graphics Processing Unit 5 monitors 6. Doppler sound output section 7 speakers 8. Operation Input Section 10 Control device 11 Transmit / Receive Control Unit 12 Filtering control unit 200 Ultrasound Probes 601 User Interface 602 Setting Area 603 Configuration Area 604 User Interface 605 Setting Area 606 User Interface 607 Settings area 608 Settings area 1001 User Interface 1002 Setting Area 1003 User Interface 1004 Setting Area 1005 Setting Area

Claims

1. A transmitting and receiving unit that transmits and receives ultrasonic waves to obtain a received signal related to the ultrasonic echo, A detection unit that detects the received signal and generates a Doppler signal, A filtering processing unit that performs filtering to cut or suppress low-frequency components contained in the Doppler signal, comprising: a filtering unit that applies a first filter to the Doppler signal to generate a first filtered Doppler signal; and a filtering unit that applies a second filter having different filter characteristics from the first filter to the Doppler signal to generate a second filtered Doppler signal; An analysis unit that performs frequency analysis on the first filtered Doppler signal to generate a spectral image signal, A generation unit that generates an audio signal based on the second filtered Doppler signal, Equipped with, The analysis unit is connected to the filtering unit such that the second filtered Doppler signal is not input and only the first filtered Doppler signal is input. The generation unit is connected to the filtering unit such that the first filtered Doppler signal is not input, but the second filtered Doppler signal is input. Ultrasound diagnostic equipment.

2. The first and second filters are configured as high-pass filters. The cutoff frequency of the second filter is higher than the cutoff frequency of the first filter. The ultrasound diagnostic apparatus according to claim 1.

3. The first and second filters are configured as high-pass filters. The gain change in the transition region of the second filter is more gradual than the gain change in the transition region of the first filter. The ultrasound diagnostic apparatus according to claim 1.

4. A user-operable first setting unit for setting the filter characteristics of the first filter, A user-operable second setting unit for setting the filter characteristics of the second filter, The ultrasound diagnostic apparatus according to claim 1, further comprising:

5. The filter characteristics of the first filter and the filter characteristics of the second filter are defined by their cutoff frequencies. The ultrasound diagnostic apparatus according to claim 4.

6. A user-operable third setting unit for setting the cutoff frequencies of the first and second filters. It also has the following features: A lower limit is set for the cutoff frequency of the second filter. If the set cutoff frequency of the second filter falls below the lower limit, the filtering unit applies the second filter having the lower limit cutoff frequency to generate the second filtered Doppler signal. The ultrasound diagnostic apparatus according to claim 1.

7. A user-operable fourth setting unit for setting the aforementioned lower limit. The ultrasound diagnostic apparatus according to claim 6, further comprising:

8. A transmitting and receiving unit that transmits and receives ultrasonic waves to obtain a received signal relating to an ultrasonic echo, A detection unit that detects the received signal and generates a Doppler signal, A filtering unit that performs filtering to cut or suppress low-frequency components included in the Doppler signal, comprising: applying a third filter to the Doppler signal to generate a first filtered Doppler signal; and applying a fourth filter having different filter characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal; An analysis unit that performs frequency analysis on the first filtered Doppler signal to generate a spectral image signal, A generation unit that generates an audio signal based on the second filtered Doppler signal, Equipped with, The third and fourth filters are configured as high-pass filters. The gain change in the transition region of the fourth filter is more gradual than the gain change in the transition region of the third filter. Ultrasound diagnostic equipment.

9. A transmitting and receiving unit that transmits and receives ultrasonic waves to obtain a received signal relating to an ultrasonic echo, A detection unit that detects the received signal and generates a Doppler signal, A filtering unit that performs filtering to cut or suppress low-frequency components included in the Doppler signal, comprising: applying a third filter to the Doppler signal to generate a first filtered Doppler signal; and applying a fourth filter having different filter characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal; An analysis unit that performs frequency analysis on the first filtered Doppler signal to generate a spectral image signal, A generation unit that generates an audio signal based on the second filtered Doppler signal, Equipped with, The third and fourth filters are configured as high-pass filters. The gain in the cutoff region of the fourth filter is higher than the gain in the cutoff region of the third filter. Ultrasound diagnostic equipment.

10. The third and fourth filters are configured as high-pass filters. The cutoff frequency of the fourth filter is higher than the cutoff frequency of the third filter. The ultrasound diagnostic apparatus according to claim 8 or 9.

11. A user-operable fifth setting unit for setting the filter characteristics of the third filter, A user-operable sixth setting unit for setting the filter characteristics of the fourth filter, The ultrasound diagnostic apparatus according to claim 8 or 9, further comprising:

12. The filter characteristics of the third filter and the fourth filter are defined by their cutoff frequencies. The ultrasound diagnostic apparatus according to claim 11.

13. The steps include transmitting and receiving ultrasound waves to obtain a received signal related to the ultrasound echo, The steps include: detecting the received signal and generating a Doppler signal; A step of performing a filtering process to cut or suppress low-frequency components included in the Doppler signal, comprising: applying a first filter to the Doppler signal to generate a first filtered Doppler signal; and applying a second filter having different filter characteristics from the first filter to the Doppler signal to generate a second filtered Doppler signal. The steps include: generating a spectral image signal by frequency analysis of the first filtered Doppler signal; The steps include generating an audio signal based on the second filtered Doppler signal, Includes, The step of generating the spectral image signal is performed using the first filtered Doppler signal without using the second filtered Doppler signal. The step of generating the sound signal uses the second filtered Doppler signal without using the first filtered Doppler signal. A method for controlling an ultrasound diagnostic device.

14. A step of transmitting and receiving ultrasonic waves to obtain a received signal relating to an ultrasonic echo, The steps include: detecting the received signal and generating a Doppler signal; A step of performing a filtering process to cut or suppress low-frequency components included in the Doppler signal, comprising: applying a third filter to the Doppler signal to generate a first filtered Doppler signal; and applying a fourth filter having different filtering characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal. The steps include: generating an image signal by frequency analysis of the first filtered Doppler signal; The steps include generating an audio signal based on the second filtered Doppler signal, Includes, The third and fourth filters are configured as high-pass filters. The gain change in the transition region of the fourth filter is more gradual than the gain change in the transition region of the third filter. A method for controlling an ultrasound diagnostic device.

15. A step of transmitting and receiving ultrasonic waves to obtain a received signal relating to an ultrasonic echo, The steps include: detecting the received signal and generating a Doppler signal; A step of performing a filtering process to cut or suppress low-frequency components included in the Doppler signal, comprising: applying a third filter to the Doppler signal to generate a first filtered Doppler signal; and applying a fourth filter having different filtering characteristics from the third filter to the first filtered Doppler signal to generate a second filtered Doppler signal. The steps include: generating an image signal by frequency analysis of the first filtered Doppler signal; The steps include generating an audio signal based on the second filtered Doppler signal, Includes, The third and fourth filters are configured as high-pass filters. The gain in the cutoff region of the fourth filter is higher than the gain in the cutoff region of the third filter. A method for controlling an ultrasound diagnostic device.

16. A control program for an ultrasound diagnostic apparatus that causes the ultrasound diagnostic apparatus to execute the control method for the ultrasound diagnostic apparatus described in any one of claims 13 to 15.

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