JP2010259672A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily perform quantitative analysis on bloodstream kinetics after examination while securing observation for bloodstream kinetics. <P>SOLUTION: In this ultrasonic diagnostic apparatus, a generated contrast image and a tissue image are displayed side by side on the right and left side of a monitor before a specified period. For example, during the specified period of performing image processing to generate an image 3 where kinetics of a very small bloodstream is extracted by the maximum value luminance retaining processing, switching to the tissue image is performed to display the contrast image and the image 3 side by side on the right and left in the monitor. After the specified period, switching to the image 3 is performed to display the contrast image and the tissue image again side by side on the right and left in the monitor. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus.

  Conventionally, compared with other medical image diagnostic apparatuses such as an X-ray diagnostic apparatus, an X-ray CT apparatus, and an MRI apparatus, an ultrasonic diagnostic apparatus can perform, for example, a heart operation by simply applying an ultrasonic probe from the body surface. It plays an important role in today's medical care as a device that can display the state of movement of the test object such as the pulsation of the baby and the movement of the fetus in real time and can perform the test repeatedly because of its high safety. In addition, ultrasonic diagnostic equipment that is not exposed to radiation has been developed to be small enough to be carried with one hand. Such ultrasonic diagnostic equipment can be easily used in medical settings such as obstetrics and home medical care. can do.

  Furthermore, in recent years, since intravenously administered ultrasound contrast agents have been commercialized, “contrast imaging” is also possible in ultrasound diagnostic apparatuses, and contrast images generated by “contrast imaging” can be used for various diagnoses. It is used. Specifically, a doctor can perform a differential diagnosis of cancer by referring to the blood flow dynamics depicted in a contrast image by contrast imaging. For example, in the case of primary liver cancer, doctors should perform benign and malignant differential diagnosis of liver tumors by complementarily using arterial blood flow information and portal blood flow information depicted in contrast images. Can do.

  In addition, in radiofrequency ablation (RFA), since the region cauterized by radio waves is not stained by the ultrasound contrast agent, “contrast imaging” is also used to determine the effect of RFA. .

  In recent years, an ultrasonic diagnostic apparatus that generates a three-dimensional ultrasonic image in real time by scanning ultrasonic waves in three dimensions using a two-dimensional array transducer ultrasonic probe has been put into practical use. By performing “contrast imaging” with an ultrasonic diagnostic apparatus, it is also possible to observe three-dimensional blood flow dynamics along the time axis.

  Here, most ultrasound contrast agents use microbubbles as a reflection source. In contrast imaging, non-fundamental components (such as harmonic components) derived from reflected waves from microbubbles. A contrast image is generated using. However, due to the sensitive nature of the micro-bubbles, the micro-bubbles are broken by the mechanical action of sound pressure, even as a result of normal ultrasonic irradiation, resulting in signal strength from the scan plane. Will fall. Therefore, in order to observe the perfusion dynamics of blood dynamically and in real time, it is necessary to relatively reduce the collapse of microbubbles due to scanning, such as by generating a contrast image by ultrasonic transmission with low sound pressure. . However, since imaging by low sound pressure ultrasonic transmission also reduces the signal / noise ratio (S / N), various signal processing methods have been devised.

  As such signal processing methods, methods such as a replenishment method (see, for example, Patent Document 1) and a MaxHold process (see, for example, Patent Document 2) are known.

  The reperfusion method uses the feature that the microbubbles of the ultrasound contrast agent collapse due to the sound pressure. First, the dynamics of the microbubbles filling the scan section under low sound pressure irradiation are observed, and then irradiation is performed. This is a technique that switches the sound pressure to high sound pressure, collapses the microbubbles in the scan section (strictly speaking, within the ultrasonic irradiation range), and observes the state of the microbubbles flowing into the scan section again. .

  In addition, “contrast imaging” using microbubbles is characterized in that micro blood flow such as capillaries that could not be realized by techniques such as color Doppler can be visualized. However, since there are only a few bubbles in the micro blood flow, the micro blood flow is not constantly shaded. For this reason, in the MaxHold process, in order to generate a contrast image in which a minute blood flow is visualized more clearly, an image in which bubbles that are irregularly visualized are superimposed in the time direction is generated and displayed. Specifically, in the MaxHold process, a contrast image in which a minute blood flow is visualized more clearly is generated by a process of holding the maximum value of luminance that changes with time at each pixel (maximum value luminance holding process). Note that in a period during which the MaxHold process is performed (for example, from 10 seconds to 30 seconds), the subject needs to hold the breath, and the examiner needs to fix the ultrasonic probe.

  By the way, in “contrast imaging”, it is necessary to discriminate between a bubble-derived signal (non-fundamental wave component) and a tissue-derived signal (fundamental wave component). The main focus is to make it. However, for example, before the administration of the ultrasound contrast agent, nothing is depicted in the displayed contrast image, so that the doctor can accurately capture the dynamic blood flow information of the region of interest to be diagnosed. Absent. In addition, when distinguishing liver tumors, after a while after the ultrasound contrast agent flows into the region of interest, the doctor and the substance around the tumor are stained to the same extent. The exact location of the tumor cannot be grasped even if only reference is made.

  For this reason, a technique for displaying in parallel a tissue image obtained by imaging a tissue using a fundamental wave component of a reflected wave and a contrast image is also known (see, for example, Patent Document 3). By using such a technique, for example, when a contrast image is generated and displayed by MaxHold processing for a certain period after administration of an ultrasound contrast agent, various display forms can be executed. Here, the form of the parallel display currently performed will be described with reference to FIGS. 11, 12, and 13. In addition, FIG.11, FIG12 and FIG.13 is a figure for demonstrating a prior art.

  For example, in the first display form shown in FIG. 11, before and after the execution of the MaxHold process, normal contrast images and tissue images that have not been subjected to the MaxHold process are displayed side by side in parallel. The contrast image (MaxHold-processed contrast image) and the tissue image are displayed side by side in parallel. In the second display mode shown in FIG. 12, the same two contrast images are displayed in parallel before and after the MaxHold process is performed. During the MaxHold process, the MaxHold process contrast image and the MaxHold process contrast image are not displayed. Are displayed in parallel on the left and right. In the third display mode shown in FIG. 13, before and after the MaxHold process, the contrast image is displayed separately. During the MaxHold process, the MaxHold process contrast image and the MaxHold process contrast image are not displayed. Display in parallel on the left and right.

Japanese Patent Laid-Open No. 11-155858 JP 2004-321688 A JP-A-9-201359

  However, all of the first, second, and third display forms described above have been difficult for doctors to grasp blood flow dynamics. That is, in the first display form, the doctor can refer to the contrast image while referring to the tissue image, but the contrast image in which the bubble-derived signal is superimposed in the time direction is displayed during the MaxHold process. Therefore, in particular, even when trying to observe the blood flow dynamics from the inflow to the outflow of the bubble, it is impossible to grasp the outflow state of the bubble.

  In the second display mode, the doctor can observe the blood flow dynamics from the inflow to the outflow of the bubble during the MaxHold processing period, but displays the same two contrast images before and after the MaxHold processing. The form becomes redundant, making it difficult for a doctor to observe blood flow dynamics.

  Further, in the third display form, avoiding redundancy due to the display of the same two contrast images, at least during the MaxHold processing period, the display position of the contrast image depicting the bubble information changes, It is difficult for a doctor to observe blood flow dynamics.

  Furthermore, when the first, second, and third display modes described above are executed, the blood flow dynamics may not be accurately quantitatively analyzed. For example, in a generally used ultrasonic diagnostic apparatus, only a moving image displayed on a monitor can be stored. Therefore, when quantitative analysis of blood flow dynamics by TIC (Time Intensity Curve) representing the concentration change along the time axis of the ultrasound contrast agent, the moving image displayed during MaxHold processing is excluded from the analysis target, It is necessary to take measures such as changing the analysis target area only during MaxHold processing. In addition, if it is possible to save the reflected wave data (raw data), even if the MaxHold process is performed, a contrast image is generated from the reflected wave data collected during the MaxHold process, Quantitative analysis can be performed, but models that can store raw data will be high-end machines with high price ranges.

  Therefore, the present invention has been made to solve the above-described problems of the prior art, and it is possible to easily perform quantitative analysis of blood flow dynamics after an examination while guaranteeing observation of blood flow dynamics. An object of the present invention is to provide an ultrasonic diagnostic apparatus that can be used.

  In order to solve the above-described problems and achieve the object, the present invention according to claim 1 is a reflected wave of an ultrasonic wave transmitted from an ultrasonic probe to a predetermined part of a subject administered with an ultrasonic contrast agent. An ultrasonic diagnostic apparatus that generates an ultrasonic image by receiving a first signal that uses the ultrasonic contrast agent that flows in the predetermined region as a reflection source, and a tissue that exists in the predetermined region. The ultrasonic wave at the time of receiving the reflected wave by using a signal acquisition unit that acquires a second signal as a reflection source separately from the reflected wave, and the first signal acquired by the signal acquisition unit A second image in which the distribution of the tissue is depicted by generating a first image depicting the distribution of the contrast agent and using the second signal obtained by the signal obtaining means. Image generating means for generating an image of Display control means for controlling the first image and the second image generated by the image generation means to be displayed in parallel on a predetermined display unit, and the image generation means is operated by an operator. In a designated designated period, a predetermined state for rendering information in which an aspect in which the distribution of the ultrasonic contrast agent changes with respect to the first image is maintained in the time axis direction or information that is differentiated in the time axis direction is depicted. A third image is generated by executing processing, and the display control unit switches the image displayed on the predetermined display unit from the second image to the third image in the designated period. And controlling the display so that the first images sequentially generated in the designated period are displayed at the same position displayed before the designated period.

  According to the first aspect of the present invention, it is possible to easily perform quantitative analysis of blood flow dynamics after an examination while ensuring observation of blood flow dynamics.

FIG. 1 is a diagram for explaining the configuration of the ultrasonic diagnostic apparatus according to the first embodiment. FIG. 2 is a diagram (1) for explaining image processing executed by the image generation unit according to the first embodiment. FIG. 3 is a diagram (2) for explaining the image processing executed by the image generation unit according to the first embodiment. FIG. 4 is a diagram for explaining the control unit according to the first embodiment. FIG. 5 is a flowchart for explaining processing of the ultrasonic diagnostic apparatus according to the first embodiment. FIG. 6 is a diagram (1) for explaining the image generation unit according to the second embodiment. FIG. 7 is a diagram (2) for explaining the image generation unit according to the second embodiment. FIG. 8 is a diagram for explaining the image generation unit according to the third embodiment. FIG. 9 is a diagram for explaining a control unit according to the third embodiment. FIG. 10 is a flowchart for explaining processing of the ultrasonic diagnostic apparatus according to the third embodiment. FIG. 11 is a diagram (1) for explaining the prior art. FIG. 12 is a diagram (2) for explaining the prior art. FIG. 13 is a diagram (3) for explaining the prior art.

  Exemplary embodiments of an ultrasonic diagnostic apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

  First, the configuration of the ultrasonic diagnostic apparatus in the present embodiment will be described. FIG. 1 is a diagram for explaining the configuration of the ultrasonic diagnostic apparatus according to the first embodiment. As shown in FIG. 1, the ultrasonic diagnostic apparatus according to the present embodiment includes an ultrasonic probe 1, a monitor 2, an input device 3, and an apparatus main body 10.

  The ultrasonic probe 1 includes a plurality of piezoelectric vibrators, and the plurality of piezoelectric vibrators generate ultrasonic waves based on a drive signal supplied from a transmission / reception unit 11 included in the apparatus main body 10 to be described later, and a subject. A reflected wave from P is received and converted into an electric signal. The ultrasonic probe 1 includes a matching layer provided on the piezoelectric vibrator, a backing material that prevents propagation of ultrasonic waves from the piezoelectric vibrator to the rear, and the like.

  When ultrasonic waves are transmitted from the ultrasonic probe 1 to the subject P, the transmitted ultrasonic waves are reflected one after another at the discontinuous surface of the acoustic impedance in the body tissue of the subject P, and the ultrasonic probe is used as a reflected wave signal. 1 is received by a plurality of piezoelectric vibrators. The amplitude of the received reflected wave signal depends on the difference in acoustic impedance at the discontinuous surface where the ultrasonic wave is reflected. Note that the reflected wave signal when the transmitted ultrasonic pulse is reflected on the moving blood flow or the surface of the heart wall depends on the velocity component of the moving body in the ultrasonic transmission direction due to the Doppler effect. And undergoes a frequency shift.

  In the present invention, even when the subject P is scanned two-dimensionally by the ultrasonic probe 1 which is a one-dimensional ultrasonic probe in which a plurality of piezoelectric vibrators are arranged in a line, the one-dimensional ultrasonic probe is used. The object P is detected by the ultrasonic probe 1 that mechanically swings the plurality of piezoelectric vibrators or the ultrasonic probe 1 that is a two-dimensional ultrasonic probe in which a plurality of piezoelectric vibrators are arranged in a two-dimensional grid. Even when scanning in three dimensions, it is applicable.

  The input device 3 includes a mouse, a keyboard, a button, a panel switch, a touch command screen, a foot switch, a trackball, and the like, accepts various setting requests from an operator of the ultrasonic diagnostic apparatus, and accepts it to the apparatus main body 10. Transfer various setting requests. Specifically, the input device 3 accepts a request for setting a region of interest or a condition setting request for various image processing from the operator.

  The monitor 2 displays a GUI (Graphical User Interface) for an operator of the ultrasonic diagnostic apparatus to input various setting requests using the input device 3 or displays an ultrasonic image generated in the apparatus main body 10. Or

  The apparatus main body 10 is an apparatus that generates an ultrasonic image based on the reflected wave received by the ultrasonic probe 1. As shown in FIG. 1, the transmission / reception unit 11, the B-mode processing unit 12, and the Doppler processing unit 13. An image generation unit 14, an image memory 15, a control unit 16, and an internal storage unit 17.

  The transmission / reception unit 11 includes a trigger generation circuit, a delay circuit, a pulsar circuit, and the like, and supplies a drive signal to the ultrasonic probe 1. The pulsar circuit repeatedly generates rate pulses for forming transmission ultrasonic waves at a predetermined rate frequency. The delay circuit also sets the delay time for each piezoelectric vibrator necessary for determining the transmission directivity by focusing the ultrasonic wave generated from the ultrasonic probe 1 into a beam shape, and for each rate pulse generated by the pulser circuit. Give to. The trigger generation circuit applies a drive signal (drive pulse) to the ultrasonic probe 1 at a timing based on the rate pulse. In other words, the delay circuit arbitrarily adjusts the transmission direction from the piezoelectric vibrator surface by changing the delay time given to each rate pulse.

  The transmission / reception unit 11 includes an amplifier circuit, an A / D converter, an adder, and the like, and performs various processes on the reflected wave signal received by the ultrasonic probe 1 to generate reflected wave data. The amplifier circuit amplifies the reflected wave signal for each channel and performs gain correction processing, and the A / D converter is necessary for A / D converting the gain-corrected reflected wave signal to determine the reception directivity. The adder performs an addition process of the reflected wave signal processed by the A / D converter to generate reflected wave data. By the addition processing of the adder, the reflection component from the direction corresponding to the reception directivity of the reflected wave signal is emphasized.

  As described above, the transmission / reception unit 11 controls transmission directivity and reception directivity in ultrasonic transmission / reception. The transmission / reception unit 11 has a function capable of instantaneously changing delay information, transmission frequency, transmission drive voltage, number of aperture elements, and the like under the control of the control unit 16 described later. The transmission / reception unit 11 can also transmit and receive different waveforms for each frame or rate.

  The B-mode processing unit 12 receives reflected wave data that is a processed reflected wave signal that has been subjected to gain correction processing, A / D conversion processing, and addition processing from the transmission / reception unit 11, and performs logarithmic amplification, envelope detection processing, and the like. As a result, data (B mode data) in which the signal intensity is expressed by brightness is generated.

  Here, the B-mode processing unit 12 can change the frequency band to be visualized by changing the detection frequency. In addition, the B-mode processing unit 12 can perform detection processing with two detection frequencies in parallel on one received data.

  By using the function of the B-mode processing unit 12, an ultrasonic contrast agent (microbubbles, bubbles) that flows in the region of interest from one received data in the region of interest of the subject P into which the ultrasonic contrast agent has been injected. Can be separated from the reflected wave data using the tissue existing in the region of interest and the reflected wave data using the tissue present in the region of interest as a reflection source. In order to observe the contrast image and the morphology, a tissue image obtained by imaging the tissue can be generated.

  Here, the contrast image is often generated mainly based on the second harmonic (second harmonic) component which is a nonlinear signal, and the tissue image for morphological observation is mainly based on the fundamental wave component. Generated. In the following, the B-mode data of the second harmonic component separated from the received data by the B-mode processing unit 12 in order to generate a contrast image is referred to as “signal 1”, and the B-mode processing is performed to generate a tissue image. The B-mode data of the fundamental wave component separated by the unit 12 from the received data is referred to as “signal 2”.

  Signal 1 and signal 2 may be separated from one piece of received data by the filtering process of the B-mode processing unit 12 or may be sequentially transmitted by the transmission / reception unit 11 under the control of the control unit 16 described later. It may be a case where the B-mode processing unit 12 separates the two reflected wave data of ultrasonic waves.

  For example, when executing the pulse inversion method, which is an imaging method for generating a contrast image in which the second harmonic component is more emphasized, the transmission / reception unit 11 shifts the phase by 180 degrees with respect to the first transmission waveform. Waveforms (waveforms with inverted amplitudes) are transmitted for the second time to generate reflected wave data. Then, the B-mode processing unit 12 adds the two reflected wave data received from the transmission / reception unit 11 to obtain “a signal in which the fundamental component is suppressed and the second harmonic component is doubled” as the signal 1. can do. In addition, the B-mode processing unit 12 acquires the signal 2 separately from either of the two reflected wave data received from the transmission / reception unit 11.

  Alternatively, the transmission / reception unit 11 alternately transmits ultrasonic waves optimized for contrast image generation and tissue image generation to generate reflected wave data, and the B-mode processing unit 12 receives from the transmission / reception unit 11 Signal 1 and signal 2 are obtained separately from each of the two reflected wave data.

  Alternatively, in order to remove the second harmonic component derived from the tissue movement due to pulsation or the like and visualize the second harmonic component derived only from the bubble as a contrast image, the transmission / reception unit 11 continuously generates waveforms having the same phase. Transmitting twice to generate two reflected wave data, and the B-mode processing unit 12 generates the difference data of the two reflected wave data received from the transmission / reception unit 11 to obtain the second harmonic component derived from the tissue movement. The case where the second harmonic component of the generated difference data is removed as the signal 1 may be used.

  The Doppler processing unit 13 performs frequency analysis on velocity information from the reflected wave data received from the transmission / reception unit 11, extracts blood flow, tissue, and contrast agent echo components due to the Doppler effect, and mobile body information such as average velocity, dispersion, and power. Is generated for multiple points (Doppler data).

  The image generation unit 14 is a B-mode image in which the intensity of the reflected wave is represented by luminance from the B-mode data generated by the B-mode processing unit 12, and an average velocity image that represents moving body information from the Doppler data generated by the Doppler processing unit 14 A Doppler image as a dispersed image, a power image, or a combination image thereof is generated as an ultrasonic image.

  Further, when contrast imaging is performed on the subject P into which the ultrasound contrast agent has been injected, the image generation unit 14 generates a contrast image from the signal 1 acquired by the B-mode processing unit 12, and the signal 2 A tissue image is generated from

  Furthermore, the image generation unit 14 is configured to display an image designated by the operator during a designated period designated by the operator based on an image processing condition setting request received from the operator by the input device 1 when contrast imaging is executed. By the processing, image processing of the contrast image is performed. The image generation unit 14 can also generate a composite image obtained by combining the two generated images. Note that the image processing executed by the image generation unit 14 during the designated period will be described in detail later.

  In the following, the contrast image is “image 1”, the tissue image is “image 2”, and the image generated as a result of performing the image processing specified by the operator on the contrast image is “image”. 3 ”in some cases.

  Here, the image generation unit 14 converts (scan converts) the scanning line signal sequence of the ultrasonic scan into a scanning line signal sequence of a video format typified by a television or the like, and generates an ultrasonic image as a display image. To do.

  Furthermore, when the subject P is scanned three-dimensionally by the ultrasonic probe 1 and three-dimensional ultrasonic image data is generated, the image generation unit 14 scans a scanning line signal sequence obtained by three-dimensional scanning. Has a function of generating volume data by a process called rendering.

  The image memory 15 is a memory for storing the ultrasonic image generated by the image generation unit 14, stores in parallel image data obtained under different transmission / reception conditions, and an image recorded by the operator during the inspection after the inspection. Can be called. The data format of the image data stored in the image memory 15 may be a data format after video format conversion displayed on the monitor 2 by the control unit 16 to be described later, or a data format before coordinate conversion that is Raw data. Good.

  The control unit 16 controls the entire processing in the ultrasonic diagnostic apparatus. Specifically, the control unit 16 is based on various setting requests input from the operator via the input device 3 and various control programs read from the internal storage unit 17 to be described later. The processing of the unit 12, the Doppler processing unit 13, and the image generation unit 14 is controlled, or the ultrasonic image stored in the image memory 15 is controlled to be displayed on the monitor 2.

  Specifically, when contrast imaging is executed, the control unit 16 determines the ultrasonic transmission / reception method by the transmission / reception unit 11 and the signal 1 and the signal by the B-mode processing unit 12 based on various setting requests and various control programs. 2 is controlled, the generation process of the contrast image and the tissue image by the image generation unit 14, the image processing of the contrast image, and the like are controlled. In addition, the control unit 16 displays a B-mode image, displays a color Doppler image, displays a contrast image and a tissue image generated by contrast imaging in parallel, or displays a composite image on the monitor 2. Control to do.

  The internal storage unit 17 stores a control program for performing ultrasonic transmission / reception, image processing, and display processing, diagnostic information (for example, patient ID, doctor's findings, etc.), various data such as a diagnostic protocol and various body marks. To do. The internal storage unit 17 is also used for storing images stored in the image memory 15 as necessary. The data stored in the internal storage unit 17 can be transferred to an external peripheral device via an interface circuit (not shown).

  As described above, the ultrasonic diagnostic apparatus according to the first embodiment uses the reflected wave of the ultrasonic wave transmitted from the ultrasonic probe 1 to the region of interest of the subject P to which the ultrasonic contrast agent is administered in order to perform contrast imaging. Receives and generates an ultrasound image, but with the display control process of the control unit 16 described in detail below, the observation of blood flow dynamics is guaranteed and quantitative analysis of blood flow dynamics after the test is easily performed The main feature is that it becomes possible.

  The display control process of the control part 16 is demonstrated using FIGS. 2 and 3 are diagrams for explaining the image processing executed by the image generation unit in the first embodiment, and FIG. 4 is a diagram for explaining the control unit in the first embodiment.

  First, for example, immediately after the ultrasound contrast agent is administered, the operator touches the subject P with the ultrasound probe 1 and then inputs an ultrasound image capturing start request through the input device 3. The image generation unit 14 sequentially generates a contrast image (image 1) and a tissue image (image 2) along the time axis and stores them in the image memory 15. Then, the control unit 16 sequentially reads out the contrast image (image 1) and the tissue image (image 2) from the image memory 15, and controls the monitor 2 to display in real time side by side in parallel. Thereby, the doctor who is the operator can accurately observe the tissue form of the region of interest with reference to the image 2 and can observe the blood flow dynamics of the region of interest with reference to the image 1. it can.

  When a request for executing predetermined image processing is received from the operator via the input device 3 for a contrast image sequentially generated along the time axis in a specified period (for example, 30 seconds), control is performed. The unit 16 controls the image generation unit 14 to execute the received image processing in the specified period.

  In this embodiment, immediately after the administration of the ultrasound contrast agent, imaging of the ultrasound image is started, and when the ultrasound image flows into the region of interest and the blood flow dynamics can be observed, the operator The case where a request for executing image processing in a specified period is input will be described. However, the present invention is not limited to this, and imaging of an ultrasound image is started before administration of an ultrasound contrast agent. However, after observing the tissue form of the region of interest and administering the ultrasound contrast agent, the operator may input a request to execute image processing in a specified period. In addition, the start point of the specified period in which the operator inputs a request to execute image processing is such that the operator who observes blood flow dynamics and tissue morphology in the region of interest of the subject P to which the ultrasound contrast agent has been administered is super It may be a point in time when the ultrasonic probe 1 transmits ultrasonic waves with a high sound pressure to collapse the bubbles in the region of interest, and again starts observing the bubbles flowing into the region of interest.

  Here, the predetermined image processing is for rendering information in which the aspect of the distribution of the ultrasonic contrast agent changes with respect to the sequentially generated contrast images or information obtained by subtracting information in the time axis direction. The above-described image 3 is generated by this image processing. Hereinafter, four specific examples of the predetermined image processing will be described with reference to FIGS. It should be noted that the subject P needs to hold his / her breath during the specified period for executing the predetermined image processing, and the examiner who is the operator needs to fix the ultrasonic probe 1.

  For example, as shown in FIG. 2A, the image generation unit 14 generates an image by holding the maximum value of the luminance that changes with time in each pixel constituting each of the contrast images sequentially generated during the designated period. The “MaxHold process contrast image” is generated as “Image 3” by executing the maximum value luminance holding process, that is, the MaxHold process. In the “MaxHold processed contrast image” as “image 3”, the dynamics of the micro blood flow from the thick blood vessel to the capillary blood vessel are depicted along the time axis.

  Alternatively, as shown in FIG. 2B, the image generation unit 14 renders pixels whose luminance exceeds a preset threshold value with the color tone assigned for each time during the maximum value luminance holding process. By further performing parametric processing, a “parametrically processed MaxHold processed contrast image” is generated as “image 3”. In the “parametrically processed MaxHold processed contrast image” as “image 3”, the difference in the inflow time of the ultrasonic contrast agent is depicted along with the dynamics of the micro blood flow.

  Alternatively, the image generation unit 14 performs a process of calculating difference information along the time axis of each pixel in each of the contrast images sequentially generated during the designated period, thereby generating a “difference contrast image” as “image 3”. Generate. For example, as shown in FIG. 3A, the image generation unit 14 calculates the difference contrast image 1 by subtracting the brightness of the corresponding pixels in the contrast image 1 and the contrast image 2 generated during the designated period. Similarly, the difference contrast image 2 is generated from the contrast image 2 and the contrast image 3. In the “difference contrast image” as “image 3”, blood flow dynamics with movement, for example, blood flow dynamics in a relatively thick blood vessel are mainly depicted.

  Alternatively, the image generation unit 14 performs a process of calculating difference information of the “MaxHold processed contrast image” sequentially generated in the second and subsequent frames with respect to the “MaxHold processed contrast image” generated first by the maximum value luminance holding process. Thus, a “difference MaxHold processed contrast image” is generated as “image 3”. For example, as illustrated in FIG. 3B, the image generation unit 14 corresponds to the MaxHold processing contrast image 1 that is the first frame in the designated period and the MaxHold processing contrast image 2 that is the second frame. The difference MaxHold processing contrast 1 is generated by subtracting the luminance of the pixels, and similarly, the difference MaxHold processing contrast 2 is obtained from the MaxHold processing contrast image 1 and the third frame MaxHold processing contrast image 3. In the “difference MaxHold processed contrast image” as “image 3”, for example, when the designated period starts from the time when the ultrasound contrast agent collapses in the region of interest due to high sound pressure, the “MaxHold processed contrast image” Since the information of the signal 1 derived from the reflection source other than the ultrasonic contrast agent depicted in “1” is removed, only the blood flow dynamics are reliably depicted.

  Here, the control unit 16 switches and displays the image displayed in parallel on the monitor 2 from the tissue image (image 2) to the image 3 in the designated period, and further relates to the contrast images (image 1) sequentially generated. Is displayed at the same position as image 1 before the specified period.

  Further, when the specified period ends, the image generation unit 14 sequentially generates the image 1 and the image 2 as before the specified period, and the control unit 16 converts the images displayed in parallel on the monitor 2 from the image 3 to the image 3. Further, the image 1 that is sequentially generated is displayed at the same position as the image 1 before and during the specified period.

  The display control by the control unit 16 described above will be described again with reference to FIG. As shown in FIG. 4, the control unit 16 displays the contrast image and the tissue image in parallel on the left and right sides of the monitor 2 before the designated period, and switches to the tissue image during the designated period to display the contrast image and the image 3. Are displayed in parallel on the left and right sides of the monitor 2, and after a specified period, the image 3 is switched to display the contrast image and the tissue image again in parallel on the left and right sides of the monitor 2. In FIG. 4, the contrast image is displayed on the left side of the monitor and the tissue image or image 3 is displayed on the right side of the monitor. However, the contrast image is displayed on the right side of the monitor and the tissue image or image 3 is displayed. May be displayed on the left side of the monitor.

  Next, processing of the ultrasonic diagnostic apparatus according to the first embodiment will be described with reference to FIG. FIG. 5 is a flowchart for explaining processing of the ultrasonic diagnostic apparatus according to the first embodiment.

  As illustrated in FIG. 5, when the ultrasound diagnostic apparatus according to the first embodiment receives an ultrasound image capturing start request from the operator via the input device 3 (Yes in step S101), the image generation unit 14 transmits and receives A contrast image and a tissue image are generated based on the signals 1 and 2 separated by the B-mode processing unit 12 from the reflected wave data received from the unit 11 (step S102).

  Then, the control unit 16 performs control so that the contrast image and the tissue image generated by the image generation unit 14 are displayed in parallel on the monitor 2 (step S103).

  After that, the control unit 16 determines whether or not a predetermined image processing execution start instruction has been received from the operator via the input device 3 together with the designated period (step S104).

  Here, when a predetermined image processing execution start instruction is not received together with the designated period (No at Step S104), the control unit 16 controls the image generation unit 14 to perform a contrast image and tissue image generation process at Step S102. In step S103, the control unit 16 performs display control processing.

  On the other hand, when a predetermined image processing execution start instruction is received together with the specified period (Yes at Step S104), the image generation unit 14 uses the signal 1 separated by the B-mode processing unit 12 from the reflected wave data received from the transmission / reception unit 11. A contrast image is generated (step S105), and an image 3 is generated from the contrast image (step S106).

  Then, the control unit 16 performs control so that the contrast image generated by the image generation unit 14 and the image 3 are displayed in parallel on the monitor 2 (step S107).

  After that, the control unit 16 determines whether or not the specified period has elapsed (step S108).

  If the specified period has not elapsed (No at Step S108), the control unit 16 controls the image generation unit 14 to perform image generation processing at Step S105 and Step S106, and the control unit 16 performs Step S107. The display control process is performed at.

  On the other hand, when the specified period has elapsed (Yes at step S108), the image generation unit 14 uses the signal 1 and the signal 2 separated by the B-mode processing unit 12 from the reflected wave data received from the transmission / reception unit 11 to generate a contrast image and a tissue image. (Step S109), and the control unit 16 controls the contrast image and the tissue image generated by the image generation unit 14 to be displayed in parallel on the monitor 2 (step S110).

  And the control part 16 determines whether the imaging | photography end request | requirement of the ultrasonic image was received from the operator via the input device 3 (step S111).

  Here, when the photographing end request is not accepted (No at Step S111), the control unit 16 controls the image generation unit 14 to perform image generation processing at Step S109, and the control unit 16 displays at Step S110. Perform control processing.

  On the other hand, when the photographing end request is received (Yes at Step S111), the control unit 16 ends the process. In addition, after the imaging | photography for a test | inspection is complete | finished, a doctor reads the moving image currently displayed on the monitor 2 from the image memory 15, and refers to a moving image again or blood flow dynamics using TIC etc. Perform quantitative analysis.

  As described above, in the first embodiment, the control unit 16 displays the contrast image and the tissue image generated by the image generation unit 14 in parallel on the left and right sides of the monitor 2 before the specified period. And the control part 16 performs the image process for drawing the information by which the aspect which the distribution of an ultrasonic contrast agent changes was hold | maintained in the time-axis direction, or the information by which the time-axis direction was differentiated, and produces | generates the image 3 During the designated period, the image is switched to the tissue image, and the contrast image and the image 3 are displayed in parallel on the left and right sides of the monitor 2, respectively. After that, the control unit 16 switches to the image 3 after the designated period, and again displays the contrast image and the tissue image in parallel on the left and right sides of the monitor 2.

  Therefore, since the contrast image is displayed throughout the imaging period, the dynamics of the ultrasound contrast agent flowing out can always be observed, and before and after the specified period, the tissue image is displayed in parallel with the contrast image in real time, and the position of the region of interest is accurately displayed. Can grasp. In the specified period in which the ultrasound probe 1 is fixed, blood flow information required by the doctor, such as a MaxHold-processed contrast image, a difference image, and a difference MaxHold image, with reference to the tissue image displayed until immediately before. Since the image 3 obtained by processing the contrast image so as to be drawn is displayed together with the contrast image, image diagnosis by a doctor can be supported. Further, since all the contrast images generated during the imaging period are stored in the moving image stored in the image memory 15 during the imaging period, even in a popular ultrasonic diagnostic apparatus that cannot store reflected wave data. Quantitative analysis of blood flow dynamics after the examination can be performed over the imaging period.

  For this reason, the ultrasonic diagnostic apparatus according to the present embodiment can easily perform quantitative analysis of blood flow dynamics after the examination after ensuring the observation of blood flow dynamics as described above. It becomes possible.

  In the second embodiment, a case where a composite image generation process is performed by the image generation unit 14 will be described with reference to FIGS. 6 and 7. 6 and 7 are diagrams for explaining the image generation unit according to the second embodiment. The configuration of the ultrasonic diagnostic apparatus in the second embodiment is the same as that of the ultrasonic diagnostic apparatus in the first embodiment described with reference to FIG.

  The image generation unit 14 according to the second embodiment generates a tissue image from the signal 2 even in the specified period, and the image 3 and the tissue image (image 2) are displayed in the specified period as illustrated in FIG. A combined image is generated, and the generated combined image is set as a display image 3 to be displayed on the monitor 2 in a specified period. For example, as illustrated in FIG. 6B, the image generation unit 14 sequentially generates a composite image along the time axis from the MaxHold processed contrast image generated from the contrast image and the tissue image. Note that the image generation unit 14 generates a display image 3 by synthesizing only the pixels having luminance exceeding the set threshold in the image 3 with the tissue image, or gives the image 3 transparency, and then the tissue image. The display image 3 superimposed on the image is generated.

  Then, the control unit 16 according to the second embodiment displays the contrast image and the tissue image in a front row display before the specified period, and switches to the tissue image during the specified period to display the contrast image and the composite image that is the display image 3. In parallel, the contrast image and the tissue image are displayed in a row again after a specified period.

  Note that the image composition processing by the image generation unit 14 may be performed before and after the specified period. For example, as shown in FIG. 7, the image generation unit 14 generates a composite image obtained by combining the contrast image and the tissue image before and after the designated period, and monitors the generated composite image before and after the designated period. Display image 2 to be displayed on the screen.

  Then, the control unit 16 according to the second embodiment displays the contrast image and the display image 2 in a table format before the specified period, and switches to the display image 2 during the specified period, so that the contrast image and the display image 3 are displayed. The composite image is displayed in parallel, and after the designated period, the contrast image and the display image 2 are displayed in a row again.

  The processing flow of the ultrasonic diagnostic apparatus in the second embodiment is the same as the processing flow of the ultrasonic diagnostic apparatus in the first embodiment described with reference to FIG. 5, and the display image 2 is generated in step S102 and step S109. Similar to the above, except that an image synthesis process is added, a tissue image is also generated from the signal 2 in step S105, and an image synthesis process is added to generate the display image 3 in step S106. Since this is a process flow, the description is omitted.

  As described above, in the second embodiment, the tissue shape information is superimposed and displayed as the image 3 even during the designated period, so that it is possible to further support image diagnosis by a doctor. Further, if an image obtained by synthesizing the tissue image and the contrast image is displayed as the image 2 before and after the designated period, the doctor can observe the blood flow dynamics and the tissue morphology at the same time by referring to the image 2. Further, it is possible to further support image diagnosis by a doctor. Also in the second embodiment, since all the contrast images generated during the imaging period are stored in the image memory 15, the quantitative analysis of the blood flow dynamics after the examination is guaranteed.

  In the third embodiment, a case where the image motion correction process is performed by the image generation unit 14 will be described with reference to FIG. FIG. 8 is a diagram for explaining the image generation unit according to the third embodiment. The configuration of the ultrasonic diagnostic apparatus in the third embodiment is the same as that of the ultrasonic diagnostic apparatus in the first embodiment described with reference to FIG.

  Here, in the designated period, since the image 3 is generated by continuously using the contrast images sequentially generated along the time axis, the examiner fixes the ultrasonic probe 1 to the subject P, The subject P needs to hold his breath. This places a burden on both the examiner and the subject P. Therefore, the image generation unit 14 according to the third embodiment performs an image motion correction process in order to reduce the burden on the examiner and the subject P.

  Hereinafter, a case where the maximum value luminance holding process is performed in the designated period will be described.

  The image generation unit 14 according to the third embodiment detects a feature region in each of the sequentially generated contrast images. For example, as shown in FIG. 8A, the image generation unit 14 uses, as a feature region, a main blood vessel staining region (main blood vessel staining region) that is always stained by an ultrasound contrast agent in a contrast image. To detect. In addition, when imaging of an ultrasound image is started before the ultrasound contrast image, the motion correction process is started from the time when the main blood vessel shadow region is detected in the contrast image.

  The image generation unit 14 then detects the position vector of the feature region detected in the first contrast image in which the feature region is first detected and the feature region detected in the second and subsequent contrast images. A motion vector (amount of movement) of the feature region is calculated from the position vector, and a corrected contrast image that has been motion-corrected is generated. For example, as shown in FIG. 8B, the image generation unit 14 corrects the corrected image from the contrast image 2 using the motion vector (movement amount 1) of the feature region calculated between the contrast image 1 and the contrast image 2. A shadow image 2 is generated, and a corrected contrast image 3 is generated from the contrast image 3 based on the motion vector (movement amount 2) of the feature region calculated between the contrast image 1 and the contrast image 3. The corrected contrast image generation process is continuously executed during the imaging period. In addition, when the start time of the designated period is a time after the bubble collapse due to high sound pressure, the motion correction process is started again from the time when the main blood vessel shadow region is detected in the contrast image.

  Further, the image generation unit 14 performs motion correction on the tissue image corresponding to the contrast image for which the motion vector is calculated using the motion vector calculated for the contrast image before and after the specified period. For example, as illustrated in FIG. 8C, the image generation unit 14 generates a corrected tissue image 2 in which the movement correction is performed on the tissue image 2 corresponding to the contrast image 2 using the movement amount 1. Then, a corrected tissue image 3 obtained by performing motion correction on the tissue image 3 corresponding to the contrast image 3 using the movement amount 2 is generated.

  Further, the image generation unit 14 corrects the corrected MaxHold processed image 1, the corrected MaxHold processed image 2, the corrected MaxHold processed image 2, as shown in FIG. 8D, for example, from the corrected contrast images sequentially generated in the specified period. The processed MaxHold processed image 3 is generated as an image 3.

  By the image processing described above, the control unit 16 in the third embodiment displays the corrected contrast image and the corrected tissue image in parallel on the left and right sides of the monitor 2 before the specified period, as shown in FIG. The corrected contrast image and the corrected image 3 (corrected MaxHold-processed contrast image) are displayed in parallel on the left and right sides of the monitor 2, and the corrected image 3 is displayed after a specified period. Then, the corrected contrast image and the corrected tissue image are displayed in parallel on the left and right sides of the monitor 2 again.

  The motion correction process described above may be executed in image processing other than the maximum value luminance holding process described in the first embodiment.

  In this embodiment, the image composition processing described in the second embodiment may be executed using a motion-corrected image. For example, the image generation unit 14 executes the tissue image generation process and the corrected tissue image generation process even during the designated period, and corrects the corrected MaxHold processed image and the correction as illustrated in FIG. It may be a case where a composite image is generated by combining with a completed tissue image and the generated composite image is used as the display image 3. Alternatively, the corrected contrast image and the corrected tissue image may be combined before and after the specified period to generate a combined image, and the generated combined image may be used as the display image 2.

  Next, processing of the ultrasonic diagnostic apparatus according to the third embodiment will be described with reference to FIG. FIG. 10 is a flowchart for explaining processing of the ultrasonic diagnostic apparatus according to the third embodiment.

  As illustrated in FIG. 10, when the ultrasound diagnostic apparatus according to the third embodiment receives an ultrasound image capturing start request from the operator via the input device 3 (Yes in step S201), the image generation unit 14 transmits and receives A contrast image and a tissue image are generated based on the signals 1 and 2 separated by the B-mode processing unit 12 from the reflected wave data received from the unit 11 (step S202).

  Then, the image generation unit 14 generates a corrected contrast image and a corrected tissue image from the movement amount (motion vector) of the feature amount region in the contrast image (step S203). Note that the processing in step S203 is skipped until a feature region is detected in the contrast image.

  After that, the control unit 16 performs control so that the corrected contrast image and the corrected tissue image generated by the image generation unit 14 are displayed in parallel on the monitor 2 (step S204).

  After that, the control unit 16 determines whether or not a predetermined image processing execution start instruction is received from the operator via the input device 3 together with the designated period (step S205).

  Here, when a predetermined image processing execution start instruction is not received together with the specified period (No at Step S205), the control unit 16 controls the image generation unit 14 to perform Steps S202 and S203. In step S204, display control processing is performed.

  On the other hand, when a predetermined image processing execution start instruction is received together with the specified period (Yes at step S205), the image generation unit 14 uses the signal 1 separated by the B-mode processing unit 12 from the reflected wave data received from the transmission / reception unit 11. A contrast image is generated (step S206), and a corrected contrast image is generated from the amount of movement of the feature amount region in the contrast image (step S207).

  Then, the image generation unit 14 generates the corrected image 3 from the corrected contrast image (step S208), and the control unit 16 uses the corrected contrast image and the corrected image 3 generated by the image generation unit 14 on the monitor 2. And control to display in parallel (step S209).

  After that, the control unit 16 determines whether or not the specified period has elapsed (step S210).

  Here, when the designated period has not elapsed (No at Step S210), the control of the control unit 16 causes the image generation unit 14 to perform Steps S206, S207, and Step S208, and the control unit 16 performs Step S209. The display control process is performed at.

  On the other hand, when the specified period has elapsed (Yes in step S210), the image generation unit 14 uses the signal 1 and the signal 2 separated by the B-mode processing unit 12 from the reflected wave data received from the transmission / reception unit 11 to provide a contrast image and a tissue image. Is generated (step S211).

  Then, the image generation unit 14 generates a corrected contrast image and a corrected tissue image from the movement amount of the feature amount region in the contrast image (step S212).

  After that, the control unit 16 performs control so that the corrected contrast image and the corrected tissue image generated by the image generation unit 14 are displayed in parallel on the monitor 2 (step S213).

  Subsequently, the control unit 16 determines whether or not an ultrasound image capturing end request has been received from the operator via the input device 3 (step S214).

  Here, when the photographing end request is not accepted (No at Step S214), the control unit 16 controls the image generation unit 14 to perform Steps S211 and S212, and the control unit 16 displays the information at Step S213. Perform control processing.

  On the other hand, when the imaging end request is received (Yes at Step S214), the control unit 16 ends the process.

  As described above, in the third embodiment, since the displayed image is motion-corrected according to the amount of movement of the subject P in the region of interest detected from the contrast image, the movement of the subject P and the region of interest The observational object depicted in the image can be prevented from moving with time due to the autonomous movement of the tissue inside, so that the burden on the subject P and the examiner can be reduced, and display is performed for image diagnosis. It is also possible to reduce the burden on the doctor staring at the image.

  In addition, during the designated period, an image obtained by synthesizing the motion corrected image 3 and the tissue image can be displayed as the image 3, so that the doctor only needs to refer to the image 3 and the blood flow required by the doctor. It is possible to observe the tissue morphology as well as information (for example, the dynamics of micro blood flow).

  In the third embodiment, the case where the motion correction process is executed over the shooting period has been described. However, the present invention is not limited to this, and the case where the motion correction process is executed only during the designated period. May be.

  Each component of each illustrated device is functionally conceptual and does not necessarily need to be physically configured as illustrated. In other words, the specific form of distribution / integration of each device is not limited to that shown in the figure, and all or a part thereof may be functionally or physically distributed or arbitrarily distributed in arbitrary units according to various loads or usage conditions. Can be integrated and configured. Further, all or any part of each processing function performed in each device may be realized by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware by wired logic.

  As described above, the ultrasonic diagnostic apparatus according to the present invention receives an ultrasonic reflected wave transmitted from an ultrasonic probe to a predetermined part of a subject to which an ultrasonic contrast agent has been administered and receives an ultrasonic image. It is useful when generating, and is particularly suitable for easily performing quantitative analysis of blood flow dynamics after an examination while ensuring observation of blood flow dynamics.

DESCRIPTION OF SYMBOLS 1 Ultrasonic probe 2 Monitor 3 Input device 10 Apparatus main body 11 Transmission / reception part 12 B mode processing part 13 Doppler processing part 14 Image generation part 15 Image memory 16 Control part 17 Internal storage part

Claims (9)

An ultrasonic diagnostic apparatus that receives an ultrasonic reflected wave transmitted from an ultrasonic probe to a predetermined part of a subject administered with an ultrasonic contrast agent and generates an ultrasonic image,
A first signal using the ultrasound contrast agent flowing through the predetermined site as a reflection source and a second signal using the tissue present in the predetermined site as a reflection source are separated from the reflected wave and acquired. Signal acquisition means for
Using the first signal acquired by the signal acquisition unit, a first image in which the distribution of the ultrasound contrast agent at the time of the reflected wave reception is depicted is generated and acquired by the signal acquisition unit Image generating means for generating a second image in which the distribution of the tissue at the time of reception of the reflected wave is depicted using the second signal;
Display control means for controlling the first image and the second image generated by the image generating means to be displayed in parallel on a predetermined display unit;
With
In the specified period specified by the operator, the image generation means is configured to change the aspect in which the distribution of the ultrasound contrast agent is changed with respect to the first image in the time axis direction or the difference in the time axis direction. A third image is generated by executing a predetermined process for rendering the information
The display control means controls to switch and display the image displayed on the predetermined display unit from the second image to the third image in the designated period, and sequentially in the designated period. An ultrasonic diagnostic apparatus that controls to display the generated first image at the same position that was displayed before the designated period.   The image generation means executes, as the predetermined processing, a maximum value luminance holding process for generating an image by holding a maximum luminance value that changes with time in each pixel constituting each of the sequentially generated first images. The ultrasonic diagnostic apparatus according to claim 1, wherein the third image is generated.   The image generating means generates the third image by rendering a pixel whose luminance exceeds a predetermined threshold with a color tone assigned every time during execution of the maximum value luminance holding processing. The ultrasonic diagnostic apparatus according to claim 2.   The image generation means is a process of generating the third image by executing a process of calculating difference information along the time axis of each pixel in the first image as the predetermined process. The ultrasonic diagnostic apparatus according to claim 1. The image generation means further generates a composite image obtained by combining the third image and the second image in the designated period,
The display control means controls to switch and display the image displayed on the predetermined display unit from the second image to the composite image generated by the image generation means during the designated period. The ultrasonic diagnostic apparatus according to claim 1. The image generation means generates a fourth image obtained by combining the first image and the second image before and after the designated period,
The display control unit performs control so that the first image and the fourth image generated by the image generation unit are displayed in parallel on the predetermined display unit before and after the specified period. 2. The ultrasonic diagnostic apparatus according to claim 1, wherein an image displayed on the predetermined display unit is controlled to be switched from the fourth image to the third image during the period. . The image generation means performs first motion-corrected first motion correction on the first image based on movement information of feature points sequentially detected in the first image in the designated period. After generating the image, the maximum value luminance holding process is executed to generate a motion-corrected third image,
The display control means controls to display the motion-corrected first image and the motion-corrected third image in parallel on the predetermined display unit in the designated period. The ultrasonic diagnostic apparatus according to 2 or 3. The image generation means sequentially performs motion correction on the first image and the second image based on movement information of feature points sequentially detected in the first image even before and after the specified period. To generate a motion corrected first image and a motion corrected second image,
The display control means controls to display the motion-corrected first image and the motion-corrected second image in parallel on the predetermined display unit before and after the specified period. The ultrasonic diagnostic apparatus according to claim 7. The image generation means generates the motion-corrected second image even in the designated period, and combines the generated motion-corrected second image and the motion-corrected third image. Generate an image,
9. The display control unit according to claim 8, wherein the display control unit performs control so that the motion-corrected first image and the motion-corrected composite image are displayed in parallel on the predetermined display unit in the designated period. The ultrasonic diagnostic apparatus as described.

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