WO2019077937A1 - Dispositif ultrasonographique, et procédé ultrasonographique - Google Patents

Dispositif ultrasonographique, et procédé ultrasonographique Download PDF

Info

Publication number
WO2019077937A1
WO2019077937A1 PCT/JP2018/035074 JP2018035074W WO2019077937A1 WO 2019077937 A1 WO2019077937 A1 WO 2019077937A1 JP 2018035074 W JP2018035074 W JP 2018035074W WO 2019077937 A1 WO2019077937 A1 WO 2019077937A1
Authority
WO
WIPO (PCT)
Prior art keywords
region
transmission
ultrasonic
interest
imaging
Prior art date
Application number
PCT/JP2018/035074
Other languages
English (en)
Japanese (ja)
Inventor
美咲 広島
貞一郎 池田
Original Assignee
株式会社日立製作所
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社日立製作所 filed Critical 株式会社日立製作所
Publication of WO2019077937A1 publication Critical patent/WO2019077937A1/fr

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/88—Sonar systems specially adapted for specific applications
    • G01S15/89—Sonar systems specially adapted for specific applications for mapping or imaging
    • G01S15/8906—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques
    • G01S15/8909—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration
    • G01S15/8915—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration using a transducer array
    • G01S15/8927—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using a static transducer configuration using a transducer array using simultaneously or sequentially two or more subarrays or subapertures
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
    • A61B8/13—Tomography
    • A61B8/14—Echo-tomography
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/88—Sonar systems specially adapted for specific applications
    • G01S15/89—Sonar systems specially adapted for specific applications for mapping or imaging
    • G01S15/8906—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques
    • G01S15/8997—Short-range imaging systems; Acoustic microscope systems using pulse-echo techniques using synthetic aperture techniques
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
    • G01S7/52017—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging
    • G01S7/52046—Techniques for image enhancement involving transmitter or receiver
    • G01S7/52047—Techniques for image enhancement involving transmitter or receiver for elimination of side lobes or of grating lobes; for increasing resolving power
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
    • G01S7/52017—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00 particularly adapted to short-range imaging
    • G01S7/5205—Means for monitoring or calibrating

Definitions

  • the present invention relates to an ultrasonic imaging apparatus and an ultrasonic transmission / reception method.
  • the ultrasonic imaging apparatus transmits an ultrasonic beam having a transmission focus at a predetermined depth from the ultrasonic element a plurality of times while shifting the position in a predetermined scanning direction with respect to the imaging area, and transmits each within the imaging area
  • the generated echoes are received by a plurality of ultrasonic elements and converted into received signals.
  • the reception signals received by the plurality of ultrasonic elements are respectively delayed (phased) according to the position of the reception focus on the reception scanning line set in the imaging region, and then added to the reception focus data.
  • Gain receiveive beamforming
  • a plurality of reception focuses are set on reception scan lines, and reception focus data is sequentially acquired (dynamic focus).
  • An image of the imaging area can be generated by setting the values of the plurality of reception focus data on the plurality of reception scanning lines set in the imaging area to the values of the pixels corresponding to the position of the reception focus.
  • the ultrasonic image In ultrasonic imaging, it is difficult to uniformly image the entire imaging range. For example, since an ultrasonic beam has the property that the highest resolution is obtained at the transmission focus, the ultrasonic image generally degrades in resolution as it goes away from the focal depth at the time of transmission. Also, the higher the scanning (transmission) density of the ultrasound beam, the better the S / N ratio and resolution of the ultrasound image, but in the sector scan that radially expands the axial direction of multiple ultrasound beams from the ultrasound probe The scan density of the ultrasound beam decreases as it gets further apart. For these reasons, the resolution of the ultrasound image produces a distribution in the depth direction.
  • the inter-transmission aperture synthesis technique synthesizes the data of the reception focus obtained by a plurality of transmissions, it takes a long time to complete the synthesis, and the number of data to be synthesized is increased to achieve high image quality. As a result, the signal-to-noise ratio of the signal at the moving part is lowered, the image may be blurred, and in some cases, the image may be lost. Therefore, there is a limitation in the part which can apply the inter-transmission aperture synthesis technique and the purpose of imaging.
  • image deterioration such as a reduction in resolution, a reduction in frame rate, a reduction in SN ratio, and generation of a virtual image occurs depending on imaging conditions and the presence or absence of movement of an imaging target. It is desirable to adjust the imaging conditions in accordance with the characteristics of the part (structure, tissue characteristics, movement) and the imaging purpose (diagnostic item, measurement item).
  • the imaging conditions transmission and reception conditions
  • the user can set appropriate transmission and reception conditions that can obtain high image quality. It's not easy.
  • An object of the present invention is to set imaging conditions so that the quality of an ultrasound image reaches a predetermined high quality in a region of interest of a user.
  • an ultrasonic imaging apparatus transmits an ultrasonic beam to an imaging region of an imaging target according to a predetermined imaging condition via an ultrasonic probe connected thereto.
  • the ultrasound probe to receive the ultrasonic wave returned from the imaging area that has received the transmission of the ultrasonic beam, the region of interest setting unit that sets the region of interest in the imaging region, and the received signal obtained
  • the image has a predetermined image quality when the image is generated using the focus data and the reception unit that generates focus data for each of a plurality of reception focuses arranged according to imaging conditions at least in the region of interest by processing. It has a decision unit which decides whether or not the image quality is reached, and changes the imaging condition if the image quality does not reach a predetermined value.
  • an imaging condition capable of obtaining an ultrasound image of a desired image quality is set. it can.
  • A is an explanatory view showing a region of interest set in the imaging region
  • (b) is an explanatory view showing a transmission mesh set in the imaging region and the region of interest
  • (c) is an imaging region It is explanatory drawing which shows the reception mesh set to the area of interest.
  • A) is explanatory drawing which shows the synthetic
  • (b) is explanatory drawing which shows the region of interest set to the site
  • FIG. 12 is an explanatory view showing a principle of calculating resolution by simulation in the second embodiment. It is a flowchart which shows operation
  • (A) is explanatory drawing which shows the position of the pixel value read from the image of a region of interest in the modification 1 of 2nd Embodiment
  • (b) is the graph which plotted the read pixel value.
  • Explanatory drawing which shows an example of the present transmission focus set to the region of interest of the modification 3 of 2nd Embodiment, and the transmission focus which the user added.
  • (A)-(c) is an explanatory view showing an example of a focus pattern of modification 4 of a 2nd embodiment, respectively. It is a flowchart which shows operation
  • (A) And (b) is explanatory drawing which shows that resolution changes with the density of a receiving scanning line.
  • the ultrasound imaging apparatus includes a region of interest setting unit 20, an ultrasound probe 21, a transmission unit 22, a reception unit 23, a determination unit 24, and an image generation unit 26. Is configured.
  • An image display unit 28 is connected to the image generation unit 26.
  • the transmission unit 22 transmits an ultrasound beam from the ultrasound probe 21 to the imaging region 11 in accordance with predetermined imaging conditions for determining the transmission focus 31 (see FIG. 2B) and the like.
  • the region of interest setting unit 20 sets the region of interest 12 in the imaging region 11 of the imaging target 10, as shown in FIGS. 1 and 2A.
  • the receiving unit 23 causes the ultrasound probe 21 to receive the ultrasound (echo, scattered wave, etc.) returning from the imaging region 11 that has received the transmission of the ultrasound beam, and for each ultrasound element of the ultrasound probe 21.
  • focus data is generated for each of a plurality of reception focuses 41 arranged according to imaging conditions at least in the region of interest 12.
  • the determination unit 24 determines whether the image reaches a predetermined image quality when an image is generated using the above-described focus data, and changes the imaging condition when the image quality does not reach a predetermined image quality. Thereby, the imaging condition which can obtain desired image quality in the region of interest 12 can be set.
  • the imaging conditions include transmission conditions of the ultrasonic beam by the transmission unit 22 and reception conditions in which the reception unit 23 generates focus data.
  • the determination unit 24 calculates a predetermined evaluation value using at least two of the part where the region of interest 12 of the imaging target 10 is set, the transmission condition, and the reception condition, and the evaluation value Whether the image satisfies a predetermined evaluation standard can be determined in advance before transmission of the ultrasonic beam, depending on whether the image satisfies a predetermined evaluation criterion.
  • the determination unit 24 may be configured to determine whether the image has reached a predetermined image quality based on the image of the region of interest 12 generated using the focus data. .
  • the determination unit 24 further obtains a frame rate determined by the imaging condition, and changes the imaging condition when the frame rate does not reach a predetermined value or when the image does not reach a predetermined image quality. desirable. As a result, since it is possible to set an imaging condition in which not only the image quality but also the frame rate reaches a predetermined value or more, it is possible to achieve both high image quality and high frame rate.
  • the ultrasound probe 21 and the image generation unit 26 may not necessarily be part of the ultrasound imaging apparatus.
  • an ultrasonic probe which is an external device may be connected, and an ultrasonic wave may be transmitted via the connected ultrasonic probe, or the focus data generated by the receiving unit 23 may be transmitted to an external image generation unit Output to generate an image.
  • a transmission / reception separation circuit 27 is provided between the transmission unit 22 and the reception unit 23 and the ultrasound probe 21 to perform transmission and reception by one ultrasound probe 21. Although arranged, the transmission / reception separation circuit 27 is not necessary when separate ultrasonic probes 21 are used for transmission and reception.
  • the determination unit 24 obtains the displacement of the region of interest in the repetition time, which is the time interval of transmission of the ultrasonic beam, as the evaluation value. By determining whether the determined displacement exceeds a predetermined value, it is determined whether the composite region width of aperture synthesis is appropriate. Then, if the determined displacement exceeds a predetermined value, the determination unit 24 changes the imaging condition.
  • imaging conditions can be set to prevent blurring of the composite image due to incoherent combining of phase-shifted signals, and uniform composite effects can be obtained according to the dynamic characteristics of the composite signal imaging target. be able to.
  • the apparatus configuration of the ultrasonic imaging apparatus of the first embodiment is shown in FIG.
  • the ultrasonic imaging apparatus according to the first embodiment has the same configuration as the apparatus shown in FIG. 1, but the determination unit 24 includes a moving speed measuring unit 29 that measures the moving speed of the region of interest 12.
  • the moving speed storage unit 30 in which a plurality of parts (for example, a heart valve, a coronary artery, an atrium, and a ventricle) of an imaging target obtained in advance and the standard moving speeds of the respective parts are associated and stored. Is connected.
  • the moving speed measurement unit 29 for example, a color Doppler imaging unit or a Doppler measurement unit which is a function widely known in the field of ultrasonic imaging can be used.
  • the region-of-interest setting unit 20 is connected to an input unit 33 that receives the selection of the region of the region of interest 12 from the user.
  • the inter-transmission combining unit 25 that performs inter-transmission aperture combining is connected to the reception unit (referred to as a reception beam former) 23.
  • the determination unit 24 includes an imaging condition setting unit 42, an evaluation value calculation unit 43, and an imaging condition determination unit 44, as shown in FIG.
  • the imaging condition setting unit 42 sets the transmission mesh (arrangement of the transmission focus 31), the reception mesh (arrangement of the reception focus), and the width w of the synthesis region 45 in the region of interest 12 set by the region of interest setting unit 20 (FIG. )) Is set.
  • the synthesis area 45 is an area for generating reception data by one transmission / reception for the purpose of inter-transmission aperture synthesis.
  • the ultrasound imaging apparatus of the first embodiment is configured to perform inter-transmission aperture synthesis by the inter-transmission combining unit 25.
  • Transmission-by-Aperture Synthetic Imaging combines (adds) N pieces of focus data obtained respectively for the same reception focus 41 in different N times of transmission for a given reception focus 41, and combines the synthesized focus data into an image. Used for generation. Therefore, in order to obtain focus data after composition, a time T proportional to the composition number N is required.
  • the region of interest 12 moves by a distance L during a time T, for example, if synthetic after-focus data is obtained for a region of interest 12 moving at a velocity v due to, for example, a breathing movement or a heart beat.
  • the reception signal from the imaging target is not coherently added, and the SN ratio of the combined focus data may be significantly reduced. In such a case, it is difficult to obtain a high quality image because the image is blurred or disappears.
  • the determination unit 24 calculates the displacement (distance) L of the region of interest 12 by using two or more of the region of interest 12 set, the transmission condition, and the reception condition. determined, if the displacement exceeds the threshold (criterion) L 0, the determination unit 24 determines that the imaging condition (transmission condition and the reception condition) is inappropriate. Thereby, the user or the determination unit 24 adjusts the transmission condition and the reception condition such that the displacement (distance) L of the region of interest 12 becomes equal to or less than the threshold (evaluation criterion) L 0 by adjusting at least one of the transmission condition and the reception condition. Conditions can be set. Therefore, it is possible to obtain an image of high image quality.
  • the threshold L 0 for example, a value smaller than the wavelength ⁇ is set.
  • transmission conditions and reception conditions for adjusting the displacement L to be equal to or less than the threshold (evaluation standard) L 0 for example, transmission intervals of transmission beams (inter-beam distance) p and reception focus 41 in one transmission. At least one of the width w of the combined area, which is an area for setting.
  • the determination unit 24 uses the moving speed v of the region of interest 12 to calculate the displacement L. For example, the determining unit 24 receives and uses the moving velocity v of the region of interest 12 obtained by the moving velocity measuring unit 29 by ultrasonic measurement (Doppler measurement or the like). Alternatively, from the moving speed storage unit 30 storing the moving speeds (predetermined moving speeds of adult valves, etc.) for each of a plurality of imaging targets obtained in advance, the judging unit 24 moves the parts of the region of interest 12 The speed may be read out. At this time, the region of the region of interest 12 may receive an input from the user, or the determination unit 24 may obtain the region based on the relationship between the positions of a plurality of regions of interest obtained in advance and the regions.
  • the transmission beam former 22 generates a transmission signal and delivers it to each ultrasonic element of the ultrasonic probe 21.
  • the ultrasonic element converts the transmission signal into an ultrasonic signal and irradiates it to the imaging target 10.
  • the transmission beam former 22 delays the transmission signal to be delivered to each ultrasonic element for each ultrasonic element so that an ultrasonic beam having a transmission focus 31 at a desired depth in a desired direction is obtained. It can be transmitted from the ultrasound probe 21. For example, as shown in FIG.
  • the transmission beam former 22 is a transmission scanning line in which a focusing type ultrasonic beam connecting the transmission focal point 31 in the imaging area 11 is set at predetermined angles in the azimuth direction. Along the line 32, it is made to transmit sequentially for a predetermined repetition time.
  • the ultrasonic beam is not limited to the focused ultrasonic beam connecting the transmission focal point 31 in the imaging area 11, and has a virtual transmission focal point 32 in front of the ultrasonic probe 21, and imaging It may be irradiated with a diffusive ultrasonic beam that spreads in the area 11.
  • the receive beamformer 23 generates focus data by processing the receive signal.
  • any method may be used as a processing method, for example, a delay addition method can be used.
  • the delay-and-add method the time difference when the ultrasonic waves virtually emitted from the reception focal point 41 reach the respective ultrasonic elements in the same phase, which are obtained in advance for each reception focal point 41, is the delay amount for each ultrasonic element Then, after delaying the received signal by delaying, it is added. Thereby, focus data on the reception focus 41 can be generated.
  • the inter-transmission combining unit 25 combines (adds) N pieces of focus data obtained for the same reception focal point 41 where the combining regions 45 overlap in different N transmissions, and obtains combined focus data.
  • the image generation unit 26 generates an ultrasound image by arranging the focus data for each reception focus 41 generated by the reception unit as the pixel value of the position of the reception focus 41.
  • the arrangement of the plurality of reception focuses 41 set in the region of interest 12 is set according to imaging conditions (reception conditions).
  • the arrangement of the reception focal point 41 may be any arrangement, and it may be arranged at a desired density on the reception scanning line set at predetermined angles in the azimuthal direction, as shown in FIG. 2 (c).
  • the grids may be arranged at intersections of grids set at desired intervals in an orthogonal coordinate system.
  • the reception focus 41 may be set for the imaging region 11 outside the region of interest 12 and the reception beam former 23 may obtain focus data not only for the region of interest 12 but also for the imaging region 11 outside thereof.
  • the density and the arrangement of the reception focal points 41 may be made different. As a result, an image of high image quality can be generated for the region of interest 11 set by the user, and an imaging region of lower image quality can be generated in a short time.
  • the determination unit 24 is configured to include a CPU and a memory here, and the following functions are realized by software when the CPU executes a program stored in advance in the memory.
  • the determination unit 24 is not limited to one realized by software, and part or all of the determination unit 24 may be a custom IC such as an application specific integrated circuit (ASIC) or a programmable IC such as a field-programmable gate array (FPGA).
  • ASIC application specific integrated circuit
  • FPGA field-programmable gate array
  • the region of interest setting unit 20 of the ultrasound imaging apparatus sets the region of interest 12 in the imaging region 11 by receiving the setting operation of the region of interest 12 by the user via the input unit 33 including a mouse and a keyboard.
  • the region-of-interest setting unit 20 causes the image display unit 28 to display an ultrasound image captured in advance by the ultrasound imaging apparatus or an ultrasound image captured at this time through the determination unit 24.
  • the region set by the user operating the input unit 33 in the imaging region 11 of the ultrasound image is received as the region of interest 12 (step 101).
  • the region of interest setting unit 20 receives selection of a part name and the like by the user via the input unit 33, and performs image processing on an ultrasonic image captured in advance or currently captured and displayed on the image display unit 28.
  • the region of interest 12 may be set to the region corresponding to the selected region name by For example, if the displayed ultrasound image is the heart and the site name selected by the user is "Valve", the moving speed of the moving image of the ultrasound image is detected as shown in FIG.
  • the range of the image of the valve may be determined by detecting pixels whose velocity is equal to or more than a predetermined value, and the region of interest 12 may be set so as to include the range of the image of the detected valve.
  • the range of movement speed to an appropriate range previously determined, it is possible to detect the range of images of coronary arteries, atria, ventricles and the like and set as the region of interest 12.
  • the initial value of the imaging condition including the width w of is set (step 103).
  • the initial value of the imaging condition including the transmission interval p and the width w of the combined area 45 may be received from the user via the input unit 33, or a predetermined value may be set.
  • the imaging condition includes transmission repetition time PRT in addition to transmission interval p and combining area width w.
  • the evaluation value calculation unit 43 of the determination unit 24 reads the velocity v of the region of interest from the movement speed measurement unit 29 or the movement speed storage unit 30. Then, the evaluation value calculation unit 43 calculates the displacement L at which the reception focal point of the region of interest 12 moves during the transmission number N for aperture synthesis using the following equation (1) (step 104).
  • the selection of the user may be accepted via the input unit 33 or may be determined in advance as to whether to use a measured value or a standard value as the moving speed v used for the calculation of the equation (1).
  • the evaluation value calculation unit 43 uses the position information of the region of interest 12 set in step 101 to represent the representative value of the movement velocity in the region of interest 12 measured by the movement velocity measurement unit 29 (average Read and use the value and maximum value). Further, when using the standard value of the part as the movement speed, the standard movement speed corresponding to the part of the region of interest 12 set in step 101 is read out from the movement speed storage unit 30 and used.
  • the evaluation value calculation unit 43 receives information from the user via the input unit 33 using the standard value of the region as the moving speed and the region of the region of interest 12 specifies the region such as the region name. Alternatively, the evaluation value calculation unit 43 may select a region corresponding to the position of the region of interest 12 set by the region of interest setting unit 20 based on the relationship between the plurality of regions in the imaging target and the standard position thereof, which has been obtained in advance. You may ask.
  • the imaging condition determination unit 44 of the determination unit 24 compares the displacement L calculated in step 104 with a predetermined reference value L 0, and in the case where L ⁇ L 0 is not satisfied, the combined area width w is previously determined. After narrowing by the defined ⁇ w (step 106), the process returns to step 102. Then, the number of repetitions m is increased by 1, and steps 103 to 106 are repeated to adjust the combined area width w. This is repeated in step 105 until the displacement L satisfies L ⁇ L 0 or the number of repetitions after the increase reaches the upper limit M (steps 102 to 107).
  • step 105 if L ⁇ L 0 is satisfied, the process proceeds to step 108 to output and set the transmission condition including the transmission interval p of step 103 to the transmission beam former 22 and combine it with the reception beam former 23. Output and set reception conditions including area width w.
  • the transmission beam former 22 generates a transmission signal for sequentially irradiating the region of interest 12 with the ultrasonic beam connecting the transmission focus to the set position at the repetition interval PRT of the set transmission condition. Then, the signal is output to each ultrasonic element of the probe 21 through the transmission / reception separation circuit 27. As a result, an ultrasonic beam that meets the transmission condition is transmitted from the probe 21.
  • the reception beam former 22 receives the reception signals output from the respective ultrasonic elements of the probe 21 that have received the echo returning from the imaging target 10 through the transmission / reception separation circuit 27. Then, according to the position of the reception focus within the synthesis area width w set as the reception condition, focus data is obtained by delaying and then adding.
  • the inter-transmission combining unit 25 performs inter-transmission aperture combining by adding the N reception data obtained respectively by N transmissions for the same reception focus, thereby performing the image processing unit 26. Output to
  • the image processing unit 26 generates an image of the region of interest 12 having the focus data after combination as the pixel value of each position (step 109). In addition, predetermined image processing is performed on the generated image of the region of interest 12 as necessary. The generated image is output to the image display unit 28 and displayed.
  • the imaging condition is set so that the displacement amount becomes smaller than the reference value, and the aperture synthesis during transmission is performed.
  • the aperture synthesis during transmission is performed.
  • the fast moving target can set the region of interest and can be imaged at high speed. Both small objects can be imaged in high quality.
  • the ultrasound image can obtain high image quality with high resolution and signal-to-noise ratio (contrast) as the ultrasound beam to be transmitted and the receiving scanning line (hereinafter also referred to as receiving beam) are denser.
  • the frame rate decreases as the number of ultrasonic beams to be transmitted increases.
  • an ultrasonic beam and reception capable of achieving both desired image quality and frame rate by evaluating the frame rate and the image quality of the acquired image while sequentially increasing the density of the ultrasonic beam or the reception scanning line Set the density of scan lines.
  • the determination unit 24 obtains a combined beam sound field obtained by combining the sound field of the ultrasonic beam determined by the transmission condition and the reception beam sound field virtually determined by the reception condition (beam sound field simulation).
  • the width of the sound field is used as an evaluation value to determine whether the resolution of the obtained image reaches a predetermined value.
  • the structure of the ultrasonic imaging apparatus according to the second embodiment is the same as that of the apparatus according to the first embodiment, but as shown in FIG. It differs from the first embodiment in that it is provided.
  • the region of interest setting unit 20 sets the region of interest 12 in the imaging region 11 by receiving the setting operation of the region of interest 12 by the user via the input unit 33 as in step 101 of the first embodiment. (Step 701).
  • the imaging condition setting unit 42 of the determination unit 24 sets the transmission mesh (arrangement of the transmission focus 31) of the initial focus pattern 81 as shown in FIG. It is assumed that the reception mesh (arrangement of reception focus), the width w of the combining area 14, and other transmission conditions and reception conditions use predetermined values.
  • the resolution calculation unit 46 determines the estimated resolution of the ultrasonic image to be captured by beam sound field simulation based on the set transmission mesh (step 703). Specifically, the synthetic beam formed by the ultrasonic beam transmitted and received under the set imaging conditions (transmission mesh and reception mesh) is determined including the action of aperture synthesis by the transmission inter-synthesis unit 25, and the synthesis is performed. The beam width R of the beam is calculated and used as a resolution index. First, as shown in FIG. 10, the resolution calculation unit 46 transmits transmission sound that is a beam sound field (distribution of beam sound pressure) of an ultrasonic beam formed by the transmission mesh that is set and other transmission conditions. The pressure P Txi is calculated.
  • the resolution calculation unit 46 determines that there is a sound field of a virtual intensity distribution with a predetermined width at the position of the reception scanning line set by the reception beam former 23 based on the reception mesh and other reception conditions.
  • the reception sound pressure P Rx is calculated.
  • the aperture synthesis by the transmission between the combining unit 25, the focal data for the same receiving focus 41 obtained from a plurality of transmission beams (signals) to be added coherently, sound field P S of the combined beam is typically It can be calculated by equation (2) by convolution calculation of the impulse response to be used.
  • the resolution calculating unit 46 all of the transmitted sound pressure P Txi combined transmission by adding the beam .SIGMA.P Txi, it calculates the sound field P S of the combined beam by the equation (2) for multiplying the received beam sound pressure P Rx. Then, the resolution calculating unit 46 obtains the R (half-value width of the beam) beam width of the sound pressure P S of the combined beam, and outputs the evaluation value calculating unit 43 as the resolution index value.
  • the evaluation value calculation unit 43 receives the resolution index value R from the resolution calculation unit 46. Further, the evaluation value calculation unit 43 calculates the frame rate FR according to the following equation (3) (step 704).
  • p is a transmission interval
  • A is the width
  • PRT is the repetition time of transmission.
  • the initial value of the imaging condition including the transmission interval p, the width A of the region of interest 12, and the repetition time PRT may be received from the user via the input unit 33, or a predetermined value may be used.
  • the imaging condition determination unit 44 compares the resolution index value R and the frame rate FR with predetermined reference values R 0 and FR 0 respectively, and determines whether both R ⁇ R 0 and FR> FR 0 are satisfied. (Step 705). If at least one of R ⁇ R 0 and FR> FR 0 is not satisfied, the process proceeds to step 706, and the transmission focus 31 is added by a predetermined number of one or more. The transmission focal point 31 to be added sets its position and the order of addition according to a predetermined additional focal point pattern 82. After the transmission focus 31 is added, the process returns to step 703, and the resolution calculation unit 46 calculates the resolution index value R based on the transmission mesh after the transmission focus 31 is added.
  • step 704 the evaluation value calculation unit 43 calculates a frame rate FR using the transmission interval p changed by the addition of the transmission focus 31 in step 706.
  • the imaging condition determination unit 44 determines the resolution index value R and the frame rate FR obtained for the transmission mesh after addition of the transmission focus 31 by comparing with the reference values R 0 and FR 0 , respectively (step 705). .
  • step 705 if at least one of R ⁇ R 0 and FR> FR 0 is not satisfied, the process proceeds to step 706 again to add transmission focal point 31 by a predetermined number, and steps 703 to 705 are repeated.
  • step 705 the process proceeds to step 706 and the imaging condition determination unit 44 outputs the transmission condition including the transmission mesh to the transmission beam former 22.
  • the setting is performed, and the receiving condition is output and set to the receiving beam former 23 (step 707).
  • the transmission beam former 22 generates a transmission signal, and the ultrasonic beam focused on the transmission focal point 31 of the transmission mesh set from the probe 21 is sequentially irradiated at the repetition time PRT. Echoes returning from the imaging object 10 are received by each ultrasound element of the probe 21 and the receive beamformer 22 obtains focus data for the receive focus of the receive mesh.
  • the inter-transmission combining unit 25 performs inter-transmission aperture combining by adding N pieces of received data obtained for the same reception focus.
  • the image processing unit 26 generates an image of the region of interest 12 using the focus data after aperture synthesis (step 708). The generated image is displayed on the image display unit 28.
  • the desired image quality and the frame rate are compatible by calculating and evaluating the frame rate and the image resolution while calculating the transmission focus 31 of the ultrasonic beam sequentially. It can set the transmission mesh that can.
  • the density of transmission and reception beams can be changed in the region of interest 12 and other regions, high-quality imaging of the region of interest without lowering the imaging rate (frame rate) can be performed. it can.
  • the resolution calculation unit 46 is configured to calculate the resolution index R by beam sound field simulation, but in the second embodiment, the determination unit 24 generates the resolution index R using focus data.
  • the size of the predetermined structure in the image of the region of interest 12 is used as an evaluation value to determine whether the resolution of the image has reached the predetermined resolution. Specifically, the size of a predetermined image in the image is used as the resolution index R.
  • the imaging condition is changed by adding the transmission focus of the ultrasonic beam in the region of interest 12 Do.
  • the region of interest setting unit 20 sets the region of interest 12
  • the imaging condition setting unit 42 sets the transmission mesh of the initial focus pattern 81 in the region of interest 12.
  • the region of interest 12 is set to the cross section of the blood vessel.
  • the imaging condition determination unit 44 sets transmission conditions including a transmission mesh in the transmission beam former 22, and receives conditions in the reception beam former 23.
  • the ultrasonic beam focused on the transmission focal point 31 of the transmission mesh set from the probe 21 is sequentially irradiated, the echo is received by the probe 21, and the reception beam former 22 receives the reception focal point of the reception mesh.
  • the during-transmission combining unit 25 performs during-transmission aperture combining, and the image processing unit 26 generates an image of the region of interest 12 using the focus data after the aperture combining.
  • the resolution calculation unit 46 reads the pixel values from the predetermined position A to A ′ of the image of the region of interest 12 as shown in FIG. 12A, and plots the pixel values as shown in FIG. 12B. Get the change curve of Then, the resolution calculation unit 46 obtains the thickness of the vascular endothelium thickness by obtaining the peak width R of the pixel value lowered by a predetermined intensity (here, 6 dB) from the peak value of the change curve of the pixel value. Output to the evaluation value calculator 43 as
  • steps 704 to 706 are performed in the same manner as the flow of FIG. Specifically, the evaluation value calculator 43 receives the resolution index value R from the resolution calculator 46, and calculates the frame rate FR (step 704).
  • the imaging condition determination unit 44 compares the resolution index value R and the frame rate FR with predetermined reference values R 0 and FR 0 respectively, and at least one of R ⁇ R 0 and FR> FR 0 is not satisfied. In the case, the process proceeds to step 706, and the transmission focus 31 is added by a predetermined number of one or more (steps 705, 706). Proceeding to step 711, steps 711, 712 and 703 to 706 are repeated, the resolution index value R is calculated again for the image obtained by the transmission condition such as the transmission mesh after the transmission focal point 31 is added, and determination is made.
  • step 705 when both the resolution index value R and the frame rate FR satisfy the reference value, the imaging condition determination unit 44 sets the transmission condition including the transmission mesh in the transmission beam former 22 and sets the transmission condition in the reception beam former 23.
  • Reception conditions are set (step 707). According to the transmission and reception conditions, transmission and reception of ultrasonic beams are performed to generate an image (step 708).
  • the resolution calculating unit 46 can obtain the resolution index R by a method of measuring the size of a predetermined image (structure) in the actually captured ultrasonic image.
  • the vascular endothelium thickness is calculated as a predetermined image (structure), but any image structure that reflects the resolution of the image may be used.
  • the determination unit 24 causes the display device (image display unit) 28 to display the image of the region of interest 12 and the input unit 33 indicates that the resolution of the image displayed by the user is satisfied. If it is determined that the resolution of the image has reached the predetermined resolution.
  • the resolution calculation unit 46 of the determination unit 24 causes the image display unit 28 to display the image (FIG. 12A) generated in step 712, and the image viewed by the user of the image currently displayed is
  • the determination unit 24 receives, via the input unit 33, an input indicating whether the resolution is satisfied. If the user is satisfied with the resolution of the displayed image, the process proceeds to step 707. If the user is not satisfied, the process proceeds to step 706 to add a transmission focus.
  • the other configuration is the same as that of the first modification.
  • the configuration of the second modification it is possible to set a transmission mesh for obtaining an image with a resolution that the user is satisfied with a small amount of calculation.
  • the image processing unit 26 causes the image display unit 28 to display the generated image.
  • the resolution calculation unit 46 calculates the resolution index value R
  • the evaluation value calculation unit 43 calculates the frame rate FR
  • the imaging condition determination unit 44 performs determination by comparing the resolution index value R and the frame rate FR with the reference value. . If at least one of the resolution index value R and the frame rate FR is equal to or greater than the reference value, the imaging condition setting unit 42 receives the position desired by the user via the input unit 33 at step 706 and transmits the transmission focus 31 to that position. Add For example, as shown in FIG.
  • the imaging condition setting unit 42 superimposes and displays the transmission mesh (transmission focal point 31) currently set on the image displayed on the image display unit 28 in step 712, and displays the image.
  • the position of the transmission focus 31 added by the user on the screen of the unit 28 is received.
  • the transmission focus 31 can be added to any position desired by the user.
  • Modification 4 of the second embodiment >> Furthermore, in the second embodiment and the first to third modifications, the transmission focal point 31 is sequentially added to the initial focus pattern 81 in step 706. However, in the fourth modification, a plurality of focal patterns are previously transmitted. The type is prepared, and in step 706, the focus pattern is replaced with a different focus pattern. Specifically, a transmission focus pattern having a larger number of transmission focal points than the current transmission focal point may be selected.
  • a plurality of types of focus patterns different in the number of arrangement or transmission focus or arrangement such as one-row arrangement, multistage arrangement, alternating arrangement are prepared in advance.
  • the imaging condition determination unit 44 determines in step 705 that the resolution index value R or the frame rate FR does not satisfy the reference value
  • the imaging condition setting unit 42 selects one focus pattern from a plurality of types of focus patterns.
  • one focus pattern may be selected from a plurality of types of focus patterns in a predetermined order, or the focus pattern may be selected based on the relationship between the resolution index value R or the frame rate FR and the reference value. May be The other configuration is the same as that of the second embodiment and the first to third modifications.
  • the resolution index value R and the frame rate FR can be largely changed by replacing the focus pattern of the transmission focus with different focus patterns, it is possible to set the focus pattern that satisfies the reference value in a short time. Is possible.
  • ⁇ Modification 5 of the second embodiment A fifth modification of the second embodiment will be described.
  • the determination unit 24 changes the imaging condition by increasing the density of the reception focus in the region of interest 12. Specifically, as shown in FIG. 15, when it is determined that the resolution index value R does not satisfy the reference (step 705), the reception mesh density is changed.
  • the imaging condition setting unit 42 sets the reception mesh (arrangement of reception focus) to the initial focus pattern.
  • the transmission conditions and the reception conditions other than the reception mesh are set to predetermined conditions.
  • the process proceeds to step 703, and the resolution calculation unit 46 generates a substantially combined beam formed by the ultrasonic beam transmitted and received under the set imaging condition (transmission mesh and reception mesh) as in the flow of FIG.
  • the beam width R of the combined beam is calculated and used as a resolution index. Since the frame rate FR does not change even if the density of the reception mesh is changed, the evaluation index calculation unit 43 does not calculate the frame rate FR, unlike the flow of FIG. If the resolution index value R is greater than or equal to the reference value, the imaging condition determination unit 44 proceeds to step 806 to increase the reception mesh density. For example, the interval q of the reception scanning lines is narrowed by a predetermined value ⁇ q. Then, the process returns to step 703, and the resolution index value R is calculated using the changed received mesh.
  • the sound pressure P Rx of the reception beam is small when the density of the reception scanning line is small by increasing the density of the reception scanning line (FIG. 16 (a))
  • the change period (the width of the peak) is smaller than in (FIG. 16 (b)). Therefore, even if the sound pressure ⁇ P Txi of the transmitted ultrasonic beam is the same, the change period (width of peak) of the sound pressure P S of the combined beam becomes smaller, and the resolution index value (half width) R is reduced. be able to.
  • reception mesh capable of enhancing resolution and achieving a desired image quality.
  • the resolution index value R may be determined from the size of a predetermined structure of the image as in the first modification.
  • the image may be displayed to the user, and whether the user is satisfied with the current resolution may be received.
  • the density of the reception mesh may be received from the user, or may be selected from patterns of a plurality of reception meshes set in advance to set the reception mesh.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Remote Sensing (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Acoustics & Sound (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Medical Informatics (AREA)
  • Veterinary Medicine (AREA)
  • Molecular Biology (AREA)
  • Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Biomedical Technology (AREA)
  • Radiology & Medical Imaging (AREA)
  • Pathology (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Biophysics (AREA)
  • Ultra Sonic Daignosis Equipment (AREA)

Abstract

La présente invention concerne dans une région d'intérêt d'un utilisateur, une condition d'imagerie définie de sorte qu'une image ultrasonore atteigne une qualité d'image prescrite. Un faisceau ultrasonore est transmis, par l'intermédiaire d'une sonde ultrasonore connectée et selon la condition d'imagerie prescrite, vers une région d'imagerie qui est soumise à l'imagerie. La région d'intérêt est réglée sur la région d'imagerie, les ondes ultrasonores revenant de la région d'imagerie qui a reçu la transmission du faisceau ultrasonore sont reçues par la sonde ultrasonore, et le signal de réception résultant est traité, moyennant quoi des données de mise au point sont générées pour chacun d'une pluralité de points focaux de réception disposés dans au moins la région d'intérêt selon la condition d'imagerie. Lorsqu'une image est générée en utilisant les données de mise au point, il est déterminé si la qualité d'image a atteint la qualité d'image prescrite. Si la qualité d'image prescrite n'a pas été atteinte, la condition d'imagerie est mise à jour.
PCT/JP2018/035074 2017-10-19 2018-09-21 Dispositif ultrasonographique, et procédé ultrasonographique WO2019077937A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2017-202744 2017-10-19
JP2017202744A JP7033430B2 (ja) 2017-10-19 2017-10-19 超音波撮像装置、および、超音波撮像方法

Publications (1)

Publication Number Publication Date
WO2019077937A1 true WO2019077937A1 (fr) 2019-04-25

Family

ID=66173633

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2018/035074 WO2019077937A1 (fr) 2017-10-19 2018-09-21 Dispositif ultrasonographique, et procédé ultrasonographique

Country Status (2)

Country Link
JP (1) JP7033430B2 (fr)
WO (1) WO2019077937A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3605143A1 (fr) * 2018-07-30 2020-02-05 Samsung Medison Co., Ltd. Appareil d'imagerie ultrasonore et procédé de commande correspondant

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003051202A1 (fr) * 2001-12-14 2003-06-26 Koninklijke Philips Electronics N.V. Système et procédé d'imagerie par ultrasons
JP2012157387A (ja) * 2011-01-28 2012-08-23 Toshiba Corp 超音波診断装置及び画像生成制御プログラム
JP2013244164A (ja) * 2012-05-25 2013-12-09 Fujifilm Corp 超音波画像生成方法および超音波画像診断装置
WO2014054469A1 (fr) * 2012-10-01 2014-04-10 オリンパスメディカルシステムズ株式会社 Dispositif d'observation par ultrasons, procédé de fonctionnement pour dispositif d'observation par ultrasons, et programme de fonctionnement pour dispositif d'observation par ultrasons

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003051202A1 (fr) * 2001-12-14 2003-06-26 Koninklijke Philips Electronics N.V. Système et procédé d'imagerie par ultrasons
JP2012157387A (ja) * 2011-01-28 2012-08-23 Toshiba Corp 超音波診断装置及び画像生成制御プログラム
JP2013244164A (ja) * 2012-05-25 2013-12-09 Fujifilm Corp 超音波画像生成方法および超音波画像診断装置
WO2014054469A1 (fr) * 2012-10-01 2014-04-10 オリンパスメディカルシステムズ株式会社 Dispositif d'observation par ultrasons, procédé de fonctionnement pour dispositif d'observation par ultrasons, et programme de fonctionnement pour dispositif d'observation par ultrasons

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3605143A1 (fr) * 2018-07-30 2020-02-05 Samsung Medison Co., Ltd. Appareil d'imagerie ultrasonore et procédé de commande correspondant
US11408996B2 (en) 2018-07-30 2022-08-09 Samsung Medison Co. Ltd. Ultrasonic imaging apparatus and method of controlling the same

Also Published As

Publication number Publication date
JP7033430B2 (ja) 2022-03-10
JP2019072423A (ja) 2019-05-16

Similar Documents

Publication Publication Date Title
JP5238692B2 (ja) 空間コンパウンディングのための遡及的、動的な送信のフォーカシング
JP4787358B2 (ja) 超音波診断装置
KR101511083B1 (ko) 합성 영상을 이용한 조직 도플러 영상 생성 장치 및 방법
JP6342212B2 (ja) 超音波診断装置
WO2012029287A1 (fr) Dispositif de diagnostic à ultrasons
JP6556445B2 (ja) 超音波診断装置、画像処理装置及び画像処理方法
US20130258805A1 (en) Methods and systems for producing compounded ultrasound images
US20090099451A1 (en) Ultrasonic imaging apparatus and a method for generating an ultrasonic image
JP6309340B2 (ja) 超音波診断装置及び超音波イメージングプログラム
US9689974B2 (en) Image forming method using ultrasound and aberration correction method
US9474510B2 (en) Ultrasound and system for forming an ultrasound image
EP2189118A1 (fr) Ultrasonographe
JP4575737B2 (ja) 超音波撮像装置
EP2638860B1 (fr) Procédé de formation de faisceau, dispositif de diagnostic à ultrasons, programme et circuit intégré
JP4594836B2 (ja) 超音波撮像装置
CN109259801B (zh) 一种剪切波弹性成像方法及装置
JP7033430B2 (ja) 超音波撮像装置、および、超音波撮像方法
US20220338843A1 (en) Ultrasound imaging device, signal processing device, and signal processing method
JP6734376B2 (ja) イメージング方法、前記方法を実施する装置、コンピュータプログラム、およびコンピュータ可読記憶媒体
JP2021058583A (ja) 超音波診断装置、及び検査方法
JP2024018506A (ja) 血流画像形成装置及び血流画像形成プログラム

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18868533

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18868533

Country of ref document: EP

Kind code of ref document: A1