Ultrasonic diagnostic apparatus and control method of ultrasonic diagnostic apparatus

Abstract

The present application provides an ultrasonic diagnostic apparatus capable of accurately measuring a left ventricular outflow tract inner diameter and a velocity-time integral value of blood flow in the left ventricular outflow tract, and a control method of the ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus includes an image recognition section (25) that recognizes a left ventricular outflow tract drawn on a cross section from an ultrasonic image; a first measurement section (26) that acquires a left ventricular outflow tract inner diameter of the left ventricular outflow tract as a first measurement value; a gate setting section (27) that sets a Doppler gate in the left ventricular outflow tract; a second measurement section (28) that measures a blood flow velocity from a Doppler shift at a position of the Doppler gate, thereby acquiring a velocity-time integral value of blood flow in the left ventricular outflow tract as a second measurement value; a determination section (29) that determines whether the first measurement value and the second measurement value are within a prescribed first allowable range and a second allowable range, respectively; and a notification section (30) that notifies a user of a determination result based on the determination section (29).

Description

Technical Field

[0001] This invention relates to an ultrasound diagnostic device for imaging the heart of a subject and a control method for the ultrasound diagnostic device. Background Technology

[0002] Previously, so-called ultrasound diagnostic devices were used to capture ultrasound images of cross-sections of the heart of the examinee, and the so-called cardiac output was calculated by analyzing the captured ultrasound images. The calculation of cardiac output was usually performed by the following steps: (1) the diameter of the left ventricular outflow tract was measured in an ultrasound image of a so-called parasternal left ventricular long axis section representing the mid-systolic phase of the heart, and the cross-sectional area of ​​the left ventricular outflow tract was calculated; (2) the velocity-time integral value of the blood flow in the left ventricular outflow tract was calculated by pulse Doppler using an ultrasound image representing a so-called apical five-chamber section or a so-called apical three-chamber section; (3) the so-called single-pass volume was calculated by the product of the cross-sectional area of ​​the left ventricular outflow tract and the velocity-time integral value of the blood flow in the left ventricular outflow tract; (4) the cardiac output was calculated by the product of the single-pass volume and the heart rate.

[0003] Thus, when measuring a single-pass volume or cardiac output, two cross-sections of the heart are usually photographed, which is why the measurement takes a lot of time. Therefore, for example, as disclosed in Patent Document 1, a single-pass volume or cardiac output can be calculated by using only an ultrasound image showing the long axis of the left ventricle parasternally or only an ultrasound image showing the five chambers of the apex of the heart to calculate the diameter of the left ventricular outflow tract and the time integral value of the velocity of blood flow in the left ventricular outflow tract.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2020-075104

[0005] However, when using the technology in Patent Document 1, the adjustment of the position or orientation of the ultrasound probe used to depict the appropriate cross-section, the configuration of the measuring line used to measure the diameter of the left ventricular outflow tract in the ultrasound image, and the configuration of the so-called Doppler gate used to measure the velocity-time integral value of blood flow in the left ventricular outflow tract in the ultrasound image all need to be performed manually by the user, such as a physician. Therefore, measurement errors sometimes occur in the diameter of the left ventricular outflow tract and the velocity-time integral value of blood flow in the left ventricular outflow tract. Thus, if measurement errors occur, it is sometimes impossible to accurately calculate the single-pass output and cardiac output. Summary of the Invention

[0006] This invention was made to eliminate these previous problems, and its purpose is to provide an ultrasound diagnostic device and a control method for the ultrasound diagnostic device that can accurately measure the inner diameter of the left ventricular outflow tract and the velocity-time integral value of the blood flow in the left ventricular outflow tract.

[0007] The above objectives can be achieved based on the following structure.

[0008] [1] An ultrasound diagnostic device, comprising:

[0009] The image acquisition unit acquires ultrasound images of a specified cross-section of the patient's heart.

[0010] The image recognition unit identifies the left ventricular outflow tract depicted on a cross-section from the ultrasound image acquired by the image acquisition unit;

[0011] The first measurement unit acquires the inner diameter of the left ventricular outflow tract, which is identified by the image recognition unit, as the first measurement value.

[0012] The gate setting unit sets a Doppler gate in the left ventricular outflow tract identified by the image recognition unit;

[0013] The second measurement unit measures blood flow velocity based on the Doppler frequency shift at the position of the Doppler gate set by the gate setting unit, thereby obtaining the velocity-time integral value of the blood flow in the left ventricular outflow tract as the second measurement value.

[0014] The determination unit determines whether the first measurement value obtained by the first measurement unit and the second measurement value obtained by the second measurement unit are within the specified first allowable range and second allowable range, respectively; and

[0015] The notification department will notify the user of the judgment result based on the judgment department's judgment.

[0016] [2] According to the ultrasonic diagnostic device described in [1], wherein,

[0017] The image acquisition unit acquires the ultrasound image of the long axis section of the left ventricle adjacent to the sternum as a specified section.

[0018] [3] According to the ultrasonic diagnostic device described in [2], wherein,

[0019] The notification department will handle the matter as follows:

[0020] If the determination unit determines that the first measurement value is outside the first permissible range, it will notify the department of a suggestion to obtain another ultrasound image of the parasternal left ventricular long axis section.

[0021] If the determination unit determines that the second measurement value is outside the second allowable range, it will notify the unit of the recommendation to re-acquire ultrasound images using the apical three-chamber section or the apical five-chamber section as the prescribed section.

[0022] [4] According to the ultrasonic diagnostic device described in [1], wherein,

[0023] The image acquisition unit acquires the ultrasound image of the three chambers of the apex of the heart as a specified cross-section.

[0024] [5] According to the ultrasonic diagnostic device described in [4], wherein,

[0025] The notification department will handle the matter as follows:

[0026] If the determination unit determines that the first measurement value is outside the first permissible range, it will recommend acquiring an ultrasound image again using the parasternal left ventricular long axis section as the specified section.

[0027] If the determination unit determines that the second measurement value is outside the second allowable range, it shall notify the user to obtain an ultrasound image of the three-chamber section of the apex of the heart again, or notify the user to obtain an ultrasound image of the five-chamber section of the apex of the heart again as the specified section.

[0028] [6] According to the ultrasonic diagnostic device described in [1], wherein,

[0029] The image acquisition unit acquires the ultrasound image of the five-chamber cross-section of the apex of the heart as a specified cross-section.

[0030] [7] The ultrasonic diagnostic device according to [6], wherein,

[0031] The notification department will handle the matter as follows:

[0032] If the determination unit determines that the first measurement value is outside the first permissible range, it will recommend acquiring an ultrasound image again using the parasternal left ventricular long axis section as the specified section.

[0033] If the determination unit determines that the second measurement value is outside the second allowable range, it shall notify the user to obtain an ultrasound image of the five-chamber section of the apex of the heart again, or notify the user to obtain an ultrasound image of the three-chamber section of the apex of the heart again as the specified section.

[0034] [8] The ultrasound diagnostic apparatus according to any one of [1] to [7], comprising a display,

[0035] The notification department will display the determination result from the decision-making department on the screen.

[0036] [9] The ultrasound diagnostic apparatus according to any one of [1] to [7], comprising a loudspeaker,

[0037] The notification unit outputs the determination result based on the determination unit through a speaker via sound.

[0038]

[10] An ultrasound diagnostic apparatus according to any one of [1] to [9], wherein,

[0039] If the angle between the measurement line when the left ventricular outflow tract diameter is measured as the first measurement value and the scan line passing through the center point of the Doppler gate is within the specified angle range, the determination unit determines that the first measurement value is outside the first allowable range.

[0040]

[11] The ultrasound diagnostic apparatus according to any one of [1] to [9], wherein,

[0041] The second measurement unit corrects the blood flow velocity based on the angle between the measurement line when the left ventricular outflow tract diameter is measured by the first measurement unit as the first measurement value and the scan line passing through the center point of the Doppler gate, and uses the corrected blood flow velocity to calculate the velocity-time integral value.

[0042]

[12] A control method for an ultrasound diagnostic device, comprising the following steps:

[0043] To acquire ultrasound images of a specified cross-section of the patient's heart;

[0044] Identify the left ventricular outflow tract depicted on the cross-section from the acquired ultrasound images;

[0045] The left ventricular outflow tract diameter of the identified left ventricular outflow tract is taken as the first measurement value;

[0046] Set a Doppler gate in the identified left ventricular outflow tract;

[0047] Blood flow velocity is measured by the Doppler frequency shift at the set Doppler gate position, and the velocity-time integral value of the blood flow in the left ventricular outflow tract is obtained as the second measurement value.

[0048] Determine whether the obtained first measurement value and the obtained second measurement value are within the specified first allowable range and second allowable range, respectively;

[0049] The judgment result will be notified to the user.

[0050] Invention Effects

[0051] The ultrasound diagnostic apparatus of the present invention comprises: an image acquisition unit for acquiring an ultrasound image of a cross-section of the heart of a specific subject; an image recognition unit for identifying a left ventricular outflow tract depicted on the cross-section from the ultrasound image acquired by the image acquisition unit; a first measurement unit for acquiring the inner diameter of the left ventricular outflow tract identified by the image recognition unit as a first measurement value; a gate setting unit for setting a Doppler gate in the left ventricular outflow tract identified by the image recognition unit; a second measurement unit for measuring blood flow velocity based on the Doppler frequency shift at the position of the Doppler gate set by the gate setting unit, thereby acquiring a velocity-time integral value of the blood flow in the left ventricular outflow tract as a second measurement value; a determination unit for determining whether the first measurement value acquired by the first measurement unit and the second measurement value acquired by the second measurement unit are within a predetermined first allowable range and a second allowable range, respectively; and a notification unit for notifying a user of the determination result based on the determination unit, thereby enabling accurate measurement of the inner diameter of the left ventricular outflow tract and the velocity-time integral value of the blood flow in the left ventricular outflow tract. Attached Figure Description

[0052] Figure 1 This is a block diagram illustrating the structure of an ultrasonic diagnostic device according to an embodiment of the present invention.

[0053] Figure 2 This is a block diagram illustrating the internal structure of the transceiver circuit in an embodiment of the present invention.

[0054] Figure 3 This is a block diagram illustrating the internal structure of the image generation unit in an embodiment of the present invention.

[0055] Figure 4 This is an example of an ultrasound image showing the long axis section of the left ventricle beside the sternum.

[0056] Figure 5 This is a diagram showing an example of an ultrasound image displaying a five-chamber cross-section of the apex of the heart.

[0057] Figure 6 This is a diagram showing an example of an ultrasound image displaying a three-chamber cross-section of the apex of the heart.

[0058] Figure 7 This is a diagram showing an example of measurement lines arranged in an ultrasound image displaying the long axis section of the left ventricle beside the sternum.

[0059] Figure 8 This is a diagram showing an example of a Doppler gate configured in an ultrasound image displaying the long axis section of the left ventricle adjacent to the sternum.

[0060] Figure 9 This is a block diagram showing the internal structure of the second measuring unit in an embodiment of the present invention.

[0061] Figure 10This is an example diagram showing the determination result of the left ventricular outflow tract diameter displayed on the monitor.

[0062] Figure 11 This is a flowchart illustrating the operation of the ultrasonic diagnostic device according to an embodiment of the present invention.

[0063] Figure 12 This is a block diagram that partially illustrates the structure of a modified example of the ultrasonic diagnostic device according to an embodiment of the present invention.

[0064] Figure 13 It is a diagram showing the angle between the scan line and the measurement line at the center of the Doppler gate in an ultrasound image displaying the long axis section of the left ventricle beside the sternum.

[0065] Symbol Explanation

[0066] 1-Ultrasonic probe, 2-Device body, 11-Voltage array, 12-Transceiver circuit, 21-Image generation unit, 22-Display control unit, 23-Display, 24-Image memory, 25-Image recognition unit, 26-First measurement unit, 27-Gate setting unit, 28-Second measurement unit, 29-Decision unit, 30-Notification unit, 31-Device control unit, 32-Input device, 33-Image acquisition unit, 34-Processor, 41-Pulse generator, 42-Amplifier Main section, 43-AD conversion unit, 44-beamformer, 45-signal processing unit, 46-DSC, 47-image processing unit, 51-orthogonal detector unit, 52-high-pass filter, 53-high-speed Fourier transform unit, 54-Doppler waveform acquisition unit, 55-integral value calculation unit, 61-speaker, A-angle, EL-scan line, G-Doppler gate, M-message, ML1-measurement line, T-left ventricular outflow tract, U1, U2, U3-ultrasound images. Detailed Implementation

[0067] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0068] The following description of the components is based on a representative embodiment of the present invention, but the present invention is not limited to this embodiment.

[0069] In addition, in this specification, the numerical range represented by “~” indicates the range included by the values ​​recorded before and after “~” as the lower limit and upper limit values.

[0070] In this specification, "same" or "identical" includes the range of error generally permissible in the technical field.

[0071] Implementation

[0072] Figure 1This diagram illustrates the structure of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. The ultrasonic diagnostic apparatus includes an ultrasonic probe 1 and an apparatus body 2 that are interconnected via so-called wired communication or so-called wireless communication.

[0073] The ultrasonic probe 1 has a transducer array 11 and a transceiver circuit 12 connected thereto.

[0074] The device main body 2 includes an image generation unit 21 connected to a transceiver circuit 12. A display control unit 22 and a display 23 are sequentially connected to the image generation unit 21. An image memory 24 and an image recognition unit 25 are also connected to the image generation unit 21. A first measurement unit 26 and a door setting unit 27 are connected to the image recognition unit 25. A second measurement unit 28 is connected to the door setting unit 27. A determination unit 29 is connected to the first measurement unit 26 and the second measurement unit 28. A notification unit 30 is connected to the determination unit 29. The notification unit 30 is connected to the display control unit 22. A device control unit 31 is connected to the transceiver circuit 12, the image generation unit 21, the image memory 24, the image recognition unit 25, the first measurement unit 26, the door setting unit 27, the second measurement unit 28, the determination unit 29, and the notification unit 30. An input device 32 is connected to the device control unit 31.

[0075] The image acquisition unit 33 is composed of the transceiver circuit 12 and the image generation unit 21. Furthermore, the processor 34 for the device main body 2 is composed of the image generation unit 21, the display control unit 22, the image recognition unit 25, the first measurement unit 26, the door setting unit 27, the second measurement unit 28, the judgment unit 29, the notification unit 30, and the device control unit 31.

[0076] The transducer array 11 of the ultrasonic probe 1 has multiple ultrasonic transducers arranged in one-dimensional or two-dimensional order. These ultrasonic transducers emit ultrasonic waves according to the drive signal supplied from the transceiver circuit 12, and receive ultrasonic echoes from the subject to output signals based on the ultrasonic echoes. Each ultrasonic transducer is constructed, for example, by forming electrodes at both ends of a piezoelectric material, including piezoelectric ceramics such as PZT (Lead Zirconate Titanate), polymer piezoelectric elements such as PVDF (Poly Vinylidene Di Fluoride), and piezoelectric single crystals such as PMN-PT (Lead Magnesium Niobate-Lead Titanate solid solution).

[0077] The image acquisition unit 33, which consists of the transceiver circuit 12 and the image generation unit 21, acquires multiple frames of ultrasound images as dynamic images of the heart of the subject by using the ultrasound probe 1 to transmit and receive ultrasound beams.

[0078] Under the control of the device control unit 31, the transceiver circuit 12 transmits ultrasonic waves from the transducer array 11 and generates an acoustic signal based on the received signal acquired by the transducer array 11. For example... Figure 2 As shown, the transceiver circuit 12 has a pulse generator 41 connected to the oscillator array 11 and an amplifier 42, an AD (Analog to Digital) converter 43 and a beamformer 44 connected in series from the oscillator array 11.

[0079] The pulse generator 41 includes, for example, multiple pulse generators, and supplies respective drive signals to multiple ultrasonic transducers by adjusting the delay amount according to the emission delay mode, so that the ultrasonic waves emitted from the multiple ultrasonic transducers of the transducer array 11 form an ultrasonic beam. The emission delay mode is selected according to the control signal from the device control unit 31. Thus, if a pulsed or continuous wave voltage is applied to the electrodes of the ultrasonic transducers of the transducer array 11, the piezoelectric element expands and contracts, generating pulsed or continuous wave ultrasonic waves from each ultrasonic transducer, and the composite wave of these ultrasonic waves forms an ultrasonic beam.

[0080] The emitted ultrasonic beam is reflected at an object such as a part of the subject being examined and propagates toward the transducer array 11 of the ultrasonic probe 1. The ultrasonic echoes propagating toward the transducer array 11 are received by each ultrasonic transducer constituting the transducer array 11. At this time, each ultrasonic transducer constituting the transducer array 11 expands and contracts by receiving the propagating ultrasonic echoes to generate received signals as electrical signals, and outputs these received signals to the amplification unit 42.

[0081] The amplification unit 42 amplifies the signals input from each ultrasonic transducer constituting the transducer array 11 and sends the amplified signals to the AD converter 43. The AD converter 43 converts the signals sent from the amplification unit 42 into digital received data. The beamformer 44 performs a so-called receiver focusing process by assigning a delay to each received data received from the AD converter 43 and adding them together. Through this receiver focusing process, an acoustic signal with a reduced focus is obtained by summing the received data converted by the AD converter 43 and obtaining an integrated phase signal.

[0082] like Figure 3 As shown, the image generation unit 21 has a structure in which the signal processing unit 45, the DSC (Digital Scan Converter) 46 and the image processing unit 47 are connected in series.

[0083] The signal processing unit 45 uses the sound velocity value set by the device control unit 31 and, based on the depth of the ultrasonic wave reflection position, corrects the attenuation caused by distance on the sound signal received from the transceiver circuit 12, and then performs envelope detection processing to generate tomographic image information related to the tissue in the subject body, i.e., a B-mode image signal.

[0084] DSC46 converts (rasterizes) the B-mode image signal generated by the signal processing unit 45 into an image signal that follows the scanning pattern of a general television signal.

[0085] After performing various necessary image processing operations, such as grayscale processing, on the B-mode image signal input from the DSC46, the image processing unit 47 sends the B-mode image signal to the display control unit 22, the image memory 24, and the image recognition unit 25. Hereinafter, the B-mode image signal for which image processing has been performed by the image processing unit 47 will be referred to as an ultrasound image.

[0086] In this invention, the image acquisition unit 33 acquires an ultrasound image of a predetermined cross-section of the heart of the subject. For example, such as... Figure 4 As schematically shown, the image acquisition unit 33 is capable of acquiring an ultrasound image representing a so-called parasternal left ventricular long-axis section. The parasternal left ventricular long-axis section includes the left ventricle, the left ventricular outflow tract T, the left atrium, and the right ventricle. Furthermore, for example, as... Figure 5 As schematically shown, the image acquisition unit 33 is capable of acquiring an ultrasound image U2 representing a five-chamber cross-section of the apex of the heart. The five-chamber cross-section of the apex is a cross-section of the heart including the left ventricle, the left ventricular outflow tract T, the left atrium, the right ventricle, and the right atrium. Furthermore, for example, as... Figure 6 As schematically shown, the image acquisition unit 33 is capable of acquiring an ultrasound image U3 representing a three-chamber cross-section of the apex of the heart. The three-chamber cross-section of the apex is a cross-section of the heart including the three chambers: the left ventricle, the left atrium, and the right ventricle. Both the five-chamber cross-section and the three-chamber cross-section of the apex include the left ventricular outflow tract T.

[0087] Image memory 24 is a memory that stores ultrasound images acquired by image acquisition unit 33. Users can use it, for example, to check the ultrasound images stored in image memory 24 after inspection. Image memory 24 can be, for example, a recording medium such as flash memory, HDD (Hard Disk Drive), SSD (Solid State Drive), FD (Flexible Disk), MO (Magneto-Optical disk), MT (Magnetic Tape), RAM (Random Access Memory), CD (Compact Disc), DVD (Digital Versatile Disc), SD card (Secure Digital card), or USB memory (Universal Serial Bus memory).

[0088] The image recognition unit 25 identifies the left ventricular outflow tract T depicted on a predetermined cross section from the ultrasound image acquired by the image acquisition unit 33. The image recognition unit 25, for example, pre-stores template data representing typical image patterns of the left ventricular outflow tract T in the parasternal long-axis section, the apical five-chamber section, and the apical three-chamber section. Using a so-called template matching method that searches ultrasound images using the template data, it can identify the left ventricular outflow tract T in the parasternal long-axis section, the apical five-chamber section, and the apical three-chamber section. The image recognition unit 25, for example, has a learned model in machine learning that has learned the image patterns of the left ventricular outflow tract T in the parasternal long-axis section, the apical five-chamber section, and the apical three-chamber section. It can also output recognition results by inputting an ultrasound image into the learned model.

[0089] The first measuring unit 26 acquires the diameter of the left ventricular outflow tract T, i.e., the inner diameter of the left ventricular outflow tract, as identified by the image recognition unit 25, as the first measuring value. For example, such as Figure 7 As shown, the first measuring unit 26 arranges a measuring line ML1 in the left ventricular outflow tract T, and can measure the length of the measuring line ML1 as the inner diameter of the left ventricular outflow tract. The first measuring unit 26 can also, for example, arrange the measuring line ML1 at a position specified by the user on the ultrasound image U1 via the input device 32.

[0090] For example, such as Figure 8As shown, the gate setting unit 27 sets a so-called Doppler gate G on the left ventricular outflow tract T identified by the image recognition unit 25. The Doppler gate G is used to measure the blood flow velocity in the Doppler gate G by a so-called pulsed Doppler method. The Doppler gate G is accompanied by a scan line EL passing through the center of the Doppler gate G. The gate setting unit 27 can also set the Doppler gate G at a position specified by the user via the input device 32, for example.

[0091] The second measuring unit 28 measures blood flow velocity based on the Doppler frequency shift at the position of the Doppler gate G set by the gate setting unit 27, thereby obtaining the velocity-time integral value of the blood flow in the left ventricular outflow tract T, i.e., the blood flow in the left ventricular outflow tract, as the second measurement value. Figure 9 As shown, the second measurement unit 28 has a structure in which an orthogonal detector 51, a high-pass filter 52, a high-speed Fourier transform unit 53, a Doppler waveform acquisition unit 54, and an integral value calculation unit 55 are connected in series.

[0092] The quadrature detector 51 converts the acoustic signal into a complex signal by mixing a carrier signal of the reference frequency into the acoustic signal received from the transceiver circuit 12 and performing quadrature detection.

[0093] The high-pass filter 52 functions as a so-called wall filter, removing frequency components originating from the movement of the body tissues of the subject from the complex signal generated by the quadrature detector 51.

[0094] The high-speed Fourier transform unit 53 performs frequency analysis and calculates blood flow velocity by performing Fourier transform on the complex signals of multiple sample points, and generates a spectrum signal.

[0095] The Doppler waveform acquisition unit 54 acquires a Doppler waveform image signal by aligning the spectral signal generated by the high-speed Fourier transform unit 53 on the time axis and using brightness to represent the magnitude of each frequency component. The Doppler waveform image signal is called a so-called Doppler image, which represents the time-varying waveform of blood flow velocity. The horizontal axis represents the time axis, the vertical axis represents the Doppler frequency shift (i.e., flow velocity), and the brightness of the waveform represents the power in each frequency component.

[0096] The integral value calculation unit 55 determines a heartbeat period in the Doppler waveform image signal and calculates the velocity time integral value by integrating the flow velocity value in the Doppler waveform image signal over a heartbeat period. For example, by analyzing the Doppler waveform image signal, the integral value calculation unit 55 determines the repeating units of the waveform in the Doppler waveform image signal, and can determine the period to which the determined repeating units belong as a heartbeat period.

[0097] By setting a Doppler gate G on the left ventricular outflow tract T in the ultrasound image U2 via the gate setting unit 27, the velocity-time integral value calculated by the integral value calculation unit 55 is obtained by integrating the velocity of the blood flow flowing in the left ventricular outflow tract T during one heartbeat. The velocity-time integral value can be used together with the left ventricular outflow tract diameter measured in an ultrasound image representing a so-called parasternal left ventricular long axis section, etc., to calculate the so-called single-shot output and cardiac output.

[0098] Furthermore, the processing of calculating the velocity-time integral value based on the orthogonal detector 51, high-pass filter 52, high-speed Fourier transform unit 53, Doppler waveform acquisition unit 54, and integral value calculation unit 55 is performed after a drive signal is sent to the transducer array 11 in a pulsed manner under the control of the transceiver circuit 12 and the device control unit 31.

[0099] The inner diameter of the left ventricular outflow tract measured by the first measuring unit 26 and the velocity-time integral value of the blood flow in the left ventricular outflow tract measured by the second measuring unit 28 are used to calculate the so-called single-pump volume and cardiac output. Specifically, the cross-sectional shape perpendicular to the blood flow direction of the left ventricular outflow tract T is approximated as a circle, and the cross-sectional area of ​​the left ventricular outflow tract T is calculated from the inner diameter of the left ventricular outflow tract. The single-pump volume can be calculated by multiplying the calculated cross-sectional area by the velocity-time integral value of the blood flow in the left ventricular outflow tract. Furthermore, the heart rate can be calculated based on the period of the repetitive waveform in the Doppler waveform image signal acquired by the Doppler waveform acquisition unit 54, and the cardiac output volume can be calculated by multiplying the calculated heart rate by the single-pump volume.

[0100] The determination unit 29 determines whether the first measurement value obtained by the first measurement unit 26 and the second measurement value obtained by the second measurement unit 28 are within a predetermined first allowable range and a second allowable range, respectively. For example, the first allowable range relative to the first measurement value, which is the diameter of the left ventricular outflow tract, can be set within a range of 1.5 cm or more and 2.5 cm or less. For example, the second allowable range relative to the second measurement value, which is the velocity-time integral value of the blood flow in the left ventricular outflow tract, can be set within a range of 16.2 cm or more and 24.2 cm or less. The first and second allowable ranges are set as numerical ranges from which, for example, the first and second measurement values ​​can be judged to be normal values ​​from a clinical point of view.

[0101] Here, if measurement errors occur in the velocity-time integral value of the left ventricular outflow tract diameter or the left ventricular outflow tract blood flow due to improper positioning of the measuring line ML1 used to measure the left ventricular outflow tract diameter or the Doppler gate G, causing it to deviate from the normal range, it may be impossible to accurately calculate the single-emission volume and cardiac output. If the first measurement value is within the first permissible range and the second measurement value is within the second permissible range, it can be determined that the single-emission volume and cardiac output can be accurately calculated.

[0102] The notification unit 30 will notify the user of the determination result based on the determination unit 29. For example, such as Figure 10 As shown, the notification unit 30 can notify the user by displaying a message M indicating the determination result on the display 23.

[0103] If the first measurement value, representing the left ventricular outflow tract diameter, falls outside the first permissible range, the notification unit 30 can recommend to the user an ultrasound image U1 depicting the parasternal long-axis section of the left ventricle. Generally, arranging the measurement line ML1 for measuring the left ventricular outflow tract diameter in the ultrasound image U1 depicting the parasternal long-axis section is sometimes easier and more accurate than arranging the measurement line ML1 in the ultrasound image U2 depicting the five-chamber section at the apex or the ultrasound image U3 depicting the three-chamber section at the apex. If the ultrasound image U1 depicting the parasternal long-axis section of the left ventricle has already been drawn, the notification unit 30 can recommend to the user that the ultrasound image U1 depicting the parasternal long-axis section of the left ventricle be redrawn by adjusting the position or orientation of the ultrasound probe 1.

[0104] If the second measurement value, which is the velocity-time integral value of the blood flow in the left ventricular outflow tract, is outside the second permissible range, the notification unit 30 can recommend to the user an ultrasound image U2 showing a five-chamber cross-section at the apex or an ultrasound image U3 showing a three-chamber cross-section at the apex. Generally, it is sometimes easier and more accurate to configure the Doppler gate G in the ultrasound image U2 showing a five-chamber cross-section at the apex or the ultrasound image U3 showing a three-chamber cross-section at the apex than in the ultrasound image U1 showing a long-axis cross-section of the left ventricle near the sternum. If one of the ultrasound images U2 showing a five-chamber cross-section at the apex or U3 showing a three-chamber cross-section at the apex has already been drawn, the notification unit 30 can recommend to the user an ultrasound image showing the other cross-section.

[0105] By confirming the determination result notified by the notification unit 30, the user adjusts the position or posture of the ultrasound probe 1, thereby enabling the appropriate depiction of an ultrasound image and accurate measurement of a first measurement value as the inner diameter of the left ventricular outflow tract and a second measurement value as the velocity-time integral value of the blood flow in the left ventricular outflow tract.

[0106] Under the control of the device control unit 31, the display control unit 22 performs prescribed processing on the ultrasonic image acquired by the image acquisition unit 33 and the content of the notification issued by the notification unit 30, and displays them on the display 23.

[0107] The display 23 displays ultrasonic images and notifications from the notification unit 30 under the control of the display control unit 22. It may include display devices such as LCD (Liquid Crystal Display) or Organic Electroluminescence Display.

[0108] The input device 32 is a device used by the user for input operations, such as a keyboard, mouse, trackball, touchpad, and touch sensor superimposed on the display 23.

[0109] In this embodiment, each process in processor 34 is executed by any computer. Furthermore, any computer can execute these processes via a processor as hardware, a program as software, or a combination thereof. In this case, the processor is configured to cooperate with the program to execute the various processes in this embodiment and can function as a unit or means in this embodiment. Moreover, the execution order of the processor-based processes is not limited to the order described and can be appropriately varied. The arbitrary computer can be a general-purpose computer, a special-purpose computer, a workstation, or other system capable of executing the processes.

[0110] The processor 34 can be composed of one or more hardware components, and the type of hardware is not limited. For example, the processor 34 can be composed of programmable logic devices such as CPUs (Central Processing Units), MPUs (Micro Processing Units), FPGAs (Field Programmable Gate Arrays), dedicated circuits for performing specific processes such as ASICs (Application Specific Integrated Circuits), GPUs (Graphics Processing Units), or NPUs (Neural Processing Units). Furthermore, the type of hardware can be a combination of different types of hardware. When multiple hardware components are configured to execute one or more processes of a certain processor, these multiple hardware components can exist in physically separate devices or in the same device. Moreover, in any embodiment, the order of the processes performed by the processor 34 is not limited to the above order and can be appropriately modified. Additionally, the hardware can be composed of circuits or the like, combining semiconductor elements.

[0111] Furthermore, the program can be software such as firmware or microcode. The program can also be, for example, a group of program modules, each of whose functions can be implemented by a processor configured to execute those functions. The program can be program code or multiple code segments stored on one or more non-transitory computer-readable media (e.g., storage media or other storage devices). The program can be divided into multiple non-transitory computer-readable media stored on physically separate devices. Program code or code segments can represent any combination of steps, functions, subroutines, routines, subroutines, modules, software packages, classes or commands, data structures, or program statements. Program code or code segments can be connected to other code segments or hardware circuitry by sending and receiving information, data, arguments, parameters, or memory contents.

[0112] Next, refer to Figure 11 The flowchart shown illustrates the operation of the ultrasound diagnostic apparatus according to the embodiment. Here, an example of acquiring an ultrasound image U1 representing the long axis section of the left ventricle beside the sternum by the image acquisition unit 33 will be described.

[0113] In step S1, the image acquisition unit 33 acquires an ultrasound image U1 representing the long axis section of the left ventricle beside the sternum. At this time, under the control of the device control unit 31, ultrasound waves are transmitted and received from multiple transducers of the transducer array 11 according to the drive signal from the pulse generator 41 of the transceiver circuit 12 of the ultrasound probe 1. The ultrasound echo from the subject body is received by multiple transducers of the transducer array 11, and the received signal, as an analog signal, is output to the amplification unit 42 and amplified. The received data is acquired by the AD conversion unit 43.

[0114] The received data is processed by beamformer 44 to achieve a receiving focus, and the resulting acoustic signal is sent to the image generation unit 21 of the main body 2. The image generation unit 21 generates an ultrasonic image. At this time, the signal processing unit 45 of the image generation unit 21 performs attenuation correction and envelope detection processing on the acoustic signal according to the depth of the ultrasonic wave reflection position. The signal is converted into an image signal following the scanning mode of a general television signal by DSC 46, and various necessary image processing such as grayscale processing is performed by the image processing unit 47. Thus, the ultrasonic image U1 generated in step S1 is sent to the display control unit 22, the image memory 24, and the image recognition unit 25.

[0115] In step S2, the image recognition unit 25 identifies the left ventricular outflow tract T depicted on the long axis section of the left ventricle beside the sternum from the ultrasound image U1 acquired by the image acquisition unit 33. The image recognition unit 25 can identify the left ventricular outflow tract T, for example, by template matching or by using a learned model in machine learning.

[0116] In step S3, the first measuring unit 26 acquires the diameter of the left ventricular outflow tract T, identified in step S2, i.e., the inner diameter of the left ventricular outflow tract, as the first measurement value. For example, as Figure 7 As shown, the first measuring unit 26 is equipped with a measuring line ML1 in the left ventricular outflow tract T, and the length of the measuring line ML1 can be measured as the inner diameter of the left ventricular outflow tract.

[0117] In step S4, for example, as Figure 8 As shown, the gate setting unit 27 sets a Doppler gate G on the left ventricular outflow tract T identified in step S2.

[0118] In step S5, the second measurement unit 28 measures the blood flow velocity based on the Doppler frequency shift at the position of the Doppler gate G set in step S4, thereby obtaining the velocity-time integral value of the blood flow in the left ventricular outflow tract T, i.e., the blood flow in the left ventricular outflow tract, as the second measurement value.

[0119] At this time, the transceiver circuit 12 controls the oscillator array 11 to transmit ultrasonic waves in a pulsed manner into the body of the test subject. The second measurement unit 28 performs orthogonal detection on the acoustic signal by mixing the carrier signal at the reference frequency with the acoustic signal received from the transceiver circuit 12 and converts it into a complex signal. Frequency components originating from the movement of the body's internal tissues are removed from the complex signal. Blood flow velocity is determined by performing Fourier transform on the complex signals of multiple sample points to generate a spectral signal. The second measurement unit 28 also acquires a Doppler waveform image signal by aligning the spectral signal on the time axis and representing the magnitude of each frequency component using brightness. A heartbeat period is determined in the Doppler waveform image signal, and the flow velocity value in the Doppler waveform image signal is integrated over time within a heartbeat period to calculate the velocity time integral value. For example, by analyzing the Doppler waveform image signal, the second measurement unit 28 can determine the repeating units of the waveform in the Doppler waveform image signal and define the period to which the determined repeating units belong as a heartbeat period.

[0120] In step S6, the determination unit 29 determines whether the first measurement value obtained in step S3 and the second measurement value obtained in step S5 are within a predetermined first allowable range and a second allowable range, respectively. For example, the determination unit 29 can set the first allowable range relative to the first measurement value, which is the diameter of the left ventricular outflow tract, to a range of 1.5 cm or more and 2.5 cm or less, and set the second allowable range relative to the second measurement value, which is the velocity-time integral value of the blood flow in the left ventricular outflow tract, to a range of 16.2 cm or more and 24.2 cm or less. The first and second allowable ranges are set to numerical ranges from a clinical point of view where the first and second measurement values ​​can be judged to be normal.

[0121] In step S7, the notification unit 30 notifies the user of the determination result from step S6. For example, such as... Figure 10 As shown, the notification unit 30 can notify the user by displaying a message M indicating the determination result on the display 23.

[0122] At this time, if the first measured value of the left ventricular outflow tract diameter is outside the first permissible range, the notification unit 30 can recommend to the user an ultrasound image U1 depicting the parasternal long axis section of the left ventricle. Generally, arranging the measurement line ML1 for measuring the left ventricular outflow tract diameter in the ultrasound image U1 depicting the parasternal long axis section is sometimes easier and more accurate than arranging the measurement line ML1 in the ultrasound image U2 depicting the five-chamber section at the apex or the ultrasound image U3 depicting the three-chamber section at the apex. If the ultrasound image U1 depicting the parasternal long axis section of the left ventricle has already been drawn, the notification unit 30 can recommend to the user that the ultrasound image U1 depicting the parasternal long axis section of the left ventricle be redrawn by adjusting the position or orientation of the ultrasound probe 1.

[0123] Furthermore, if the velocity-time integral value of the blood flow in the left ventricular outflow tract, i.e., the second measurement value, is outside the second permissible range, the notification unit 30 can recommend to the user an ultrasound image U2 showing a five-chamber cross-section at the apex or an ultrasound image U3 showing a three-chamber cross-section at the apex. Generally, it is sometimes easier and more accurate to configure the Doppler gate G in the ultrasound image U2 showing a five-chamber cross-section at the apex or the ultrasound image U3 showing a three-chamber cross-section at the apex than to configure the Doppler gate G in the ultrasound image U1 showing a long-axis cross-section of the left ventricle beside the sternum. If one of the ultrasound images U2 showing a five-chamber cross-section at the apex or U3 showing a three-chamber cross-section at the apex has already been drawn, the notification unit 30 can recommend to the user an ultrasound image showing the other cross-section.

[0124] In step S7, the user confirms the determination result of step S6. If at least one of the first and second measurements is found to be abnormal, the user can adjust the position and orientation of the ultrasound probe 1 to make its value normal. As a result, the user can properly draw an ultrasound image and accurately measure the first measurement as the diameter of the left ventricular outflow tract and the second measurement as the velocity-time integral value of the blood flow in the left ventricular outflow tract.

[0125] If step S7 is completed in this manner, then according to Figure 11 The operation of the ultrasound diagnostic device is completed as shown in the flowchart. Then, for example, using the first measurement value obtained in step S3 and the second measurement value obtained in step S5, the single-pass volume or cardiac output can be accurately calculated.

[0126] Based on the above, in the ultrasound diagnostic apparatus according to an embodiment of the present invention, the first measuring unit 26 acquires the left ventricular outflow tract diameter as a first measured value, the second measuring unit 28 measures the blood flow velocity based on the Doppler frequency shift at the position of the Doppler gate G, thereby acquiring the velocity-time integral value of the left ventricular outflow tract blood flow as a second measured value, the determination unit 29 determines whether the first measured value and the second measured value are within a predetermined first allowable range and a second allowable range, respectively, and the notification unit 30 notifies the user of the determination result based on the determination unit 29. Therefore, the left ventricular outflow tract diameter and the velocity-time integral value of the left ventricular outflow tract blood flow can be accurately measured.

[0127] Furthermore, the case where the transceiver circuit 12 is configured in the ultrasonic probe 1 has been described, but the transceiver circuit 12 can also be configured in the main body 2 of the device.

[0128] Furthermore, the case where the image generation unit 21 is disposed on the main body 2 of the device has been described, but the image generation unit 21 may also be disposed on the ultrasonic probe 1.

[0129] The main body 2 of the device can be a fixed type, a portable type that is easy to carry, or a handheld type, such as a smartphone or tablet. Thus, there is no particular limitation on the types of devices that constitute the main body 2 of the device.

[0130] An example has been described whereby the notification unit 30 notifies the user of the determination result of the determination unit 29 by displaying it on the monitor 23; however, the notification method based on the notification unit 30 is not particularly limited to this. For example, such as Figure 12 As shown, when the ultrasound diagnostic device is equipped with a speaker 61, the notification unit 30 can also output the judgment result of the judgment unit 29 from the speaker 61 via voice.

[0131] When the first measurement unit 29 measures the diameter of the left ventricular outflow tract as the first measurement value using the first measurement unit 26, if the angle between the measurement line ML1 and the scan line EL passing through the center point of the Doppler gate G is within a specified angle range, for example, within the range of 80 to 90 degrees in the ultrasound image U1 representing the parasternal long axis section of the left ventricle, it can determine that the first measurement value is outside the first allowable range. Normally, the component of the original blood flow velocity obtained through the Doppler gate G is in the direction orthogonal to the measurement direction, i.e., the scan line EL passing through the center point of the Doppler gate G. Therefore, when the angle between the measurement line ML1 and the scan line EL passing through the center point of the Doppler gate G is within the specified angle range, the value of the obtained component becomes very small, and sometimes an accurate value cannot be obtained as the first measurement value.

[0132] The result of the user adjusting the position and orientation of the ultrasound probe 1 sometimes deviates from the direction of the blood flow measurement based on the Doppler gate G, i.e., the direction orthogonal to the scan line EL passing through the center point of the Doppler gate G, and is roughly the direction of travel of the left ventricular outflow tract T. Through the Doppler gate G, the component of the original blood flow velocity along the measurement direction, i.e., the direction of the scan line EL passing through the center point of the Doppler gate G, can be obtained. However, if the direction along the scan line EL deviates from the direction roughly orthogonal to the direction of travel of the left ventricular outflow tract T, the difference between the measured blood flow velocity and the original value becomes larger.

[0133] Since the direction along the measuring line ML1 is considered to be approximately orthogonal to the direction of travel of the left ventricular outflow tract T, the second measuring section 28, for example, Figure 13As shown, the blood flow velocity can be corrected based on the angle A between the measurement line ML1 and the scan line EL passing through the center point of the Doppler gate G, and the corrected blood flow velocity can be used to calculate the velocity-time integral value. If the velocity-time integral value calculated based on the Doppler gate G is denoted as MV1, and the corrected velocity-time integral value is denoted as MV2, then since there is simply the relationship MV2 = MV1 × cos(A), the corrected velocity-time integral value can be calculated using MV1 = MV2 / cos(A). Here, cos is the cosine function.

Claims

1. An ultrasonic diagnostic device, comprising: The image acquisition unit acquires ultrasound images of a specified cross-section of the patient's heart. The image recognition unit identifies the left ventricular outflow tract depicted on the cross section from the ultrasound image acquired by the image acquisition unit; The first measuring unit acquires the inner diameter of the left ventricular outflow tract as identified by the image recognition unit as the first measuring value. The gate setting unit sets a Doppler gate in the left ventricular outflow tract identified by the image recognition unit; The second measurement unit measures blood flow velocity based on the Doppler frequency shift at the position of the Doppler gate set by the gate setting unit, thereby obtaining the velocity-time integral value of the blood flow in the left ventricular outflow tract as the second measurement value. The determination unit determines whether the first measurement value obtained by the first measurement unit and the second measurement value obtained by the second measurement unit are within the specified first allowable range and second allowable range, respectively; and The notification department will notify the user of the determination result based on the determination result of the determination department.

2. The ultrasonic diagnostic device according to claim 1, wherein, The image acquisition unit acquires the ultrasound image of the long axis section of the left ventricle beside the sternum as the specified section.

3. The ultrasonic diagnostic device according to claim 2, wherein, The notification department performs the following processing: If the determination unit determines that the first measurement value is outside the first allowable range, it will notify the unit of a suggestion to obtain the ultrasound image again for the parasternal left ventricular long-axis section. If the determination unit determines that the second measurement value is outside the second allowable range, it shall notify the suggestion to acquire the ultrasound image again using the apical three-chamber section or the apical five-chamber section as the prescribed section.

4. The ultrasonic diagnostic device according to claim 1, wherein, The image acquisition unit acquires an ultrasound image of the three chambers of the apex of the heart as the specified cross-section.

5. The ultrasonic diagnostic device according to claim 4, wherein, The notification department performs the following processing: If the determination unit determines that the first measurement value is outside the first allowable range, it provides a suggestion to acquire the ultrasound image again using the parasternal left ventricular long axis section as the specified section. If the determination unit determines that the second measurement value is outside the second allowable range, it may suggest acquiring the ultrasound image again for the three-chamber section of the apex of the heart, or it may suggest acquiring the ultrasound image again using the five-chamber section of the apex of the heart as the specified section.

6. The ultrasonic diagnostic device according to claim 1, wherein, The image acquisition unit acquires an ultrasound image of the five-chamber cross-section of the apex of the heart as the specified cross-section.

7. The ultrasonic diagnostic device according to claim 6, wherein, The notification department performs the following processing: If the determination unit determines that the first measurement value is outside the first allowable range, it provides a suggestion to acquire the ultrasound image again using the parasternal left ventricular long axis section as the specified section. If the determination unit determines that the second measurement value is outside the second allowable range, it may suggest obtaining the ultrasound image again for the five-chamber section of the apex of the heart, or it may suggest obtaining the ultrasound image again using the three-chamber section of the apex of the heart as the specified section.

8. The ultrasound diagnostic apparatus according to any one of claims 1 to 7, comprising a display. The notification unit will display the determination result based on the determination unit on the display.

9. The ultrasound diagnostic apparatus according to any one of claims 1 to 7, comprising a loudspeaker, The notification unit outputs the determination result based on the determination unit via voice from the speaker.

10. The ultrasonic diagnostic apparatus according to any one of claims 1 to 7, wherein, If the angle between the measurement line when the first measurement unit measures the inner diameter of the left ventricular outflow tract as the first measurement value and the scan line passing through the center point of the Doppler gate is within a specified angle range, the determination unit determines that the first measurement value is outside the first allowable range.

11. The ultrasonic diagnostic apparatus according to any one of claims 1 to 7, wherein, The second measuring unit corrects the blood flow velocity based on the angle between the measuring line when the left ventricular outflow tract diameter is measured by the first measuring unit as the first measurement value and the scanning line passing through the center point of the Doppler gate, and uses the corrected blood flow velocity to calculate the velocity-time integral value.

12. A control method for an ultrasound diagnostic device, comprising the following steps: To acquire ultrasound images of a specified cross-section of the patient's heart; Identify the left ventricular outflow tract depicted on the cross section from the acquired ultrasound images; The left ventricular outflow tract inner diameter of the identified left ventricular outflow tract is obtained as the first measurement value; A Doppler gate is set in the identified left ventricular outflow tract; Blood flow velocity is measured based on the Doppler frequency shift at the set Doppler gate position, thereby obtaining the velocity-time integral value of the left ventricular outflow tract blood flow as the second measurement value; Determine whether the first measurement value and the second measurement value obtained are within the specified first allowable range and second allowable range, respectively; The judgment result will be notified to the user.

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