JP4621578B2 - Ultrasonic diagnostic equipment - Google Patents

Description

  The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic diagnostic apparatus that images a motion of a target tissue.

  2. Description of the Related Art An ultrasonic diagnostic apparatus that images a motion of a target tissue is known. For example, the ultrasonic diagnostic apparatus described in Patent Document 1 forms a contour image in which the contour of a target tissue is clarified from a two-dimensional ultrasound image, stores the contour image in a memory for each frame, and stores the contour image in the memory. A displacement image corresponding to the difference is formed from the past contour image and the current contour image, and a displacement history image obtained by sequentially synthesizing the displacement images with time is displayed. This ultrasonic diagnostic apparatus is used, for example, for diagnosis of abnormal movement of the myocardium, and can display the movement state of the myocardium between the diastole and the systole of the ventricle over time. It has a tremendous effect in the diagnosis.

  This ultrasonic diagnostic apparatus also has a related improvement technique because of its high practical value. For example, a technique is known in which a displacement history image is clarified by performing a coloring process on the displacement image for each frame formed as described above. That is, a plurality of displacement images subjected to the coloring process corresponding to each frame are combined, and a displacement history image generated as a result is displayed like a contour line of a map colored at each height.

  Furthermore, Patent Document 2 discloses a technique for displaying a displacement history image when no stress is applied to the heart and a displacement history image when stress is applied in parallel in the same display image. Yes. This facilitates comparison of the state before and after loading in the stress echo method.

  Motion images such as displacement history images shown in Patent Document 1 and Patent Document 2 are extremely useful for diagnosis of a heart that moves periodically.

  Incidentally, a technique for realizing imaging of the heart from a viewpoint different from a motion image such as a displacement history image is also known. For example, Patent Literature 3 discloses a technique for displaying a cardiac diastole end image and a systolic end image side by side.

Japanese Patent No. 3045642 JP 2005-218713 A JP-T-2004-514526

  As described above, the motion images such as the displacement history images shown in Patent Document 1 and Patent Document 2 are extremely useful for diagnosis of a heart that performs periodic motion. Against the background of these excellent technologies, the inventors of the present application have continued research and development on devices useful for diagnosis of target tissues that perform periodic motion.

  The present invention has been made in this background, and an object of the present invention is to provide an apparatus that facilitates comparison of movements in a plurality of different periods within the same period.

  In order to achieve the above object, an ultrasonic diagnostic apparatus according to a preferred aspect of the present invention includes a transmission / reception unit that transmits and receives ultrasonic waves to a target tissue that performs periodic motion to acquire echo data; A motion image forming unit that forms a motion image reflecting the motion of the target tissue based on the echo data; and a display image forming unit that forms a display image including the motion image. Forming a plurality of motion images corresponding to a plurality of different periods in the same cycle with respect to a target tissue that performs a periodic motion, and the display image forming unit includes a plurality of motion images corresponding to a plurality of different periods in the same cycle. A display image is formed by arranging the motion images arranged side by side.

  In a desirable mode, the motion image forming unit forms an image reflecting the displacement of the contour of the target tissue as the motion image. In a preferred aspect, the target tissue is a heart that performs a contraction-expansion exercise, and the motion image forming unit forms, as the motion image, an image reflecting a displacement of the heart wall accompanying the contraction-expansion exercise. Features.

  In a preferred aspect, the display image forming unit forms a display image in which a plurality of motion images corresponding to a plurality of different periods within the same heartbeat are arranged. In a preferred aspect, the motion image forming unit forms a motion image during the contraction period and a motion image during the expansion period, and the display image formation unit arranges the motion image during the contraction period and the motion image during the expansion period within the same heartbeat. A display image arranged is formed.

  In a desirable aspect, the contraction period and the expansion period are set with reference to an R wave included in an electrocardiographic waveform obtained from a heart which is a target tissue, and the motion image forming unit includes a contraction period within the set contraction period. Then, the motion image of the expansion period is formed in the set expansion period, and the display image forming unit forms the motion image of the contraction period and the motion of the expansion period formed in stages. A display image in which images are arranged side by side is formed.

  According to the present invention, it is possible to easily compare exercise states in a plurality of different periods within the same cycle with respect to a target tissue that periodically moves.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.

  FIG. 1 shows a preferred embodiment of an ultrasonic diagnostic apparatus according to the present invention, and FIG. 1 is a block diagram showing the overall configuration thereof.

  The probe 10 is an ultrasonic probe that transmits and receives ultrasonic waves. The probe 10 has an array transducer composed of a plurality of vibration elements, and an ultrasonic beam having directivity is formed by electronically controlling the plurality of vibration elements. Further, the direction of the ultrasonic beam is changed by electronically controlling the plurality of vibration elements, and the ultrasonic beam is scanned in the space including the target tissue. The examiner brings the probe 10 into contact with the subject so that the ultrasonic beam captures the subject tissue of the subject. The target tissue in the present embodiment is a tissue that periodically moves, and an example thereof is the heart. When performing a diagnosis of the heart, the probe 10 is brought into contact with the chest of the subject, for example.

  The transmission / reception unit 12 outputs to the probe 10 a transmission pulse that is delay-controlled for each vibration element included in the transducer array. The delay amount for each vibration element is controlled so that the transmitted ultrasonic wave forms a beam having directivity, and is controlled according to the direction of the formed beam. Further, the transmission / reception unit 12 performs phasing addition of the reception signals for each vibration element obtained from the probe 10. The received signal is converted from an analog signal to a digital signal, and an echo data string along the direction of the ultrasonic beam is formed and output to the DSC 14.

  Incidentally, a memory 32 is provided between the transmission / reception unit 12 and the DSC 14 so that the echo data sequence output from the transmission / reception unit 12 is temporarily stored in the memory 32, and the echo data sequence is supplied to the DSC 14 via the memory 32. Also good. By storing the echo data sequence from the latest echo data sequence up to a plurality of heartbeats in the memory 32, the echo data sequence within the plurality of heartbeats can be read later to realize loop reproduction or the like.

  A DSC (digital scan converter) 14 stores an echo data sequence along the ultrasonic beam output from the transmission / reception unit 12 in a built-in frame memory, and rearranges the echo data in an order suitable for the subsequent processing, and converts the echo data. Output.

  The motion image forming unit 16 forms a heart motion image (motion image data) based on the echo data output from the DSC 14. For example, the technique described in Patent Document 1 is used to form the motion image. That is, a contour image in which the contour of the inner wall of the heart is clarified is formed from the tomographic image of the heart obtained based on the echo data, the contour image is stored for each frame, and the stored past contour image and the current contour image are stored. A displacement image corresponding to these differences is formed from the images, and a displacement history image obtained by sequentially synthesizing the displacement images over time is formed as a motion image.

  For this reason, the motion image forming unit 16 first binarizes echo data including various pixel values based on a predetermined threshold value, and extracts a binarized image obtained by extracting a portion corresponding to the heart chamber of the heart. Form. Alternatively, the motion image forming unit 16 uses a reference point artificially set in the center portion of the heart chamber, sets a plurality of reference lines radially from the reference point, and performs edge detection on each reference line. By doing so, the boundary between the myocardium and the heart chamber may be detected, and the inner region of the boundary may be extracted as the heart chamber. Of course, the heart chamber portion may be extracted by using not only these methods but also a conventionally known method.

  Then, the motion image forming unit 16 compares the previous frame and the latest frame based on the binarized image obtained by extracting the cardiac chamber portion output for each frame, and the cardiac chamber between the temporal phases. Displacement images that are the different parts of are formed. The frame to be compared with the frame at the latest time phase may be a frame at the past time phase, and is not limited to the frame before the one time phase. Further, the motion image forming unit 16 performs a coloring process corresponding to the time phase on the displacement image formed for each time phase, and forms a displacement history image in which a plurality of time phase displacement images are sequentially superimposed.

  The motion image forming unit 16 extracts a boundary line between the myocardium and the heart chamber using binarization processing or the like instead of the method of forming a displacement image that is a different portion of the heart chamber, and the boundary line is extracted. By capturing over a plurality of frames, a displacement history image may be formed by performing a coloring process on a gap between boundary lines between time phases.

  Incidentally, a memory 34 referred to by the motion image forming unit 16 may be provided. Then, by storing in the memory 34 the displacement history images from the latest displacement history image to a plurality of heartbeats before, the displacement history images within the plurality of heartbeats can be read later to realize loop reproduction or the like. .

  FIG. 2 is a schematic diagram showing a displacement history image when the heart chamber contracts. According to this, the initial displacement image 52 is displayed at the outermost part of the displacement history image 50, and the displacement image is added to the inner side of the initial displacement image 52 as the contraction of the heart chamber proceeds (time becomes new). Is displayed. In the drawing, only the outer ring of the heart chamber of each time phase is shown as a contour line, but in actuality, coloring processing according to the time phase is performed between the contour lines, and a plurality of color bands are used. An annular image is formed.

  Further, the displacement history image when the heart chamber is expanded also has the same form as the image shown in FIG. That is, when the heart chamber expands, an initial displacement image is displayed in the innermost part of the displacement history image 50, and a displacement image is additionally displayed outward as the expansion of the heart chamber progresses. As a result, a contour-line image similar to the displacement history image 50 in the contraction shown in FIG. 2 is formed. Of course, if there is a difference in the shape of the heart chamber between the systole and the diastole, the appearance of the displacement history image 50 is different between the systole and the diastole. Incidentally, in this embodiment, as will be described in detail below, two displacement history images 50 of a systole and a diastole within the same heartbeat are displayed in parallel.

  Returning to FIG. 1, the display image forming unit 18 includes a tomographic image (tomographic image data) based on echo data output from the DSC 14, a displacement history image (displacement history image data) formed by the motion image forming unit 16, and Display image data is formed based on various data provided from the control unit 30. A display image 22 corresponding to the display image data is displayed on the monitor 20. In the display image 22, a contraction image during the contraction period of the heart and an expansion image during the expansion period are arranged side by side.

  The control unit 30 functions as a system controller that controls each unit in the ultrasonic diagnostic apparatus of FIG. For example, based on the instructor's instruction input via the operation panel 36, the ultrasonic diagnostic apparatus is operated in the instructed mode. Incidentally, the operation panel 36 is an input device such as a trackball, a keyboard, or a touch panel. An electrocardiographic waveform is supplied from the subject to the control unit 30 via the electrocardiograph 40. The control unit 30 extracts the timing of the R wave from the electrocardiogram waveform, and outputs the waveform data of the electrocardiogram waveform to the display image forming unit 18 to cause the monitor 20 to output the electrocardiogram waveform. Further, the control unit 30 provides the motion image forming unit 16 with the start / end points of the contraction period and the start / end points of the expansion period set with reference to the R wave of the electrocardiogram waveform.

  Next, the display image 22 displayed on the monitor 20 will be described.

  FIG. 3 is a diagram for explaining a display image 22 displayed on the monitor 20 of the ultrasonic diagnostic apparatus of FIG. Hereinafter, the display image 22 will be described with reference to FIG. In addition, the part already shown in FIG. 1 is attached | subjected and demonstrated with the code | symbol of FIG. The display image 22 is an image displayed on the monitor 20 based on the display image data formed by the display image forming unit 18.

  The display image 22 in FIG. 3 includes a left screen 60L and a right screen 60R. The left screen 60 </ b> L has a configuration in which the motion image 62 is superimposed on the B-mode image 66. The B-mode image 66 is formed by the display image forming unit 18 based on the echo data output from the DSC 14. By continuously transmitting and receiving ultrasonic waves, echo data is continuously output from the DSC 14, and the display image forming unit 18 forms a B-mode image 66 of a moving image from the continuously supplied echo data.

  The motion image 62 is formed by the motion image forming unit 16 based on echo data output from the DSC 14. As described above, the motion image forming unit 16 performs the coloring process corresponding to the time phase on the displacement image formed for each time phase, and sequentially superimposes the displacement images of a plurality of time phases, thereby moving the motion image. A displacement history image which is the image 62 is formed.

  At that time, a displacement history image during the contraction period of the heart is formed on the left screen 60L. That is, the motion image 62 (displacement history image) reflecting the displacement of the heart wall in the contraction direction is formed within the period from the contraction start time SS indicating the start of the contraction period to the contraction end time SE indicating the end. In FIG. 3, the motion image 62 (displacement history image) shows only the outer ring of the heart chamber of each time phase as a contour line, but actually, according to the time phase between the contour lines. A coloring process is performed to form an annular image with a plurality of color bands.

  On the other hand, the right screen 60 </ b> R has a configuration in which the motion image 64 is superimposed on the B-mode image 66. The B-mode image 66 is formed by the display image forming unit 18 based on the echo data output from the DSC 14. The same B-mode image 66 is displayed on the right screen 60R and the left screen 60L.

  The motion image 64 is formed by the motion image forming unit 16 based on echo data output from the DSC 14. The motion image 64 is formed in the motion image forming unit 16 by the same formation method as the motion image 62 on the left screen 60L. However, a displacement history image in the expansion period of the heart is formed on the right screen 60R. That is, the motion image 64 (displacement history image) reflecting the displacement of the heart wall in the expansion direction is formed within the period from the expansion start time DS indicating the start of the expansion period to the expansion end time DE indicating the end. . In FIG. 3, the motion image 64 (displacement history image) shows only the outer ring of the heart chamber of each time phase as a contour line, but actually, according to the time phase between the contour lines. A coloring process is performed to form an annular image with a plurality of color bands.

  Thus, in this embodiment, the displacement history image (motion image 62) in the contraction period is displayed on the left screen 60L, and the displacement history image (motion image 64) in the expansion period is displayed on the right screen 60R. Each of the motion image 62 and the motion image 64 is subjected to coloring processing (not shown), but it is desirable to perform coloring processing based on different primary colors in the contraction period and the expansion period. For example, the displacement history image (motion image 62) in the contraction period is subjected to coloring processing based on yellow or red, and the displacement history image (motion image 64) in the expansion period is based on blue or green. A coloring process is performed. This facilitates the discrimination between the contraction period and the expansion period.

  The display image 22 in FIG. 3 includes an electrocardiogram waveform display 70 and a set period display 80. The electrocardiogram waveform display 70 displays an electrocardiogram waveform obtained by the electrocardiograph 40. The electrocardiographic waveform obtained by the electrocardiograph 40 is output as waveform data to the display image forming unit 18 via the control unit 30. In the display image forming unit 18, the electrocardiogram is directly below the right screen 60R and the left screen 60L. A shape display 70 is inserted.

  The set period display 80 is a display mode that visually indicates a contraction start time SS indicating the start of the contraction period, a contraction end time SE indicating the end, an expansion start time DS indicating the start of the expansion period, and an expansion end time DE indicating the end. It is. The contraction start time SS and the like are set as follows by the examiner with reference to the R wave included in the electrocardiogram waveform.

  In general, the R wave of the electrocardiogram waveform (the waveform portion that protrudes greatly in the electrocardiogram waveform display 70) corresponds to the end diastole of the heart. The examiner sets the time from the appearance timing of the R wave to the contraction start time SS via the operation panel 36. The appearance timing of the R wave of the electrocardiogram waveform is detected by the control unit 30, and the control unit 30 sets the contraction start point SS based on the appearance timing of the R wave and the time set by the operator. Incidentally, the contraction start point SS may be set at the same timing as the R wave. In addition, the contraction end time SE, the expansion start time DS, and the expansion end time DE are also set by setting the same method as the method for setting the contraction start time SS, that is, by setting the time from the appearance timing of the R wave. The contraction end time SE and the expansion start time DS may be configured to be always set at exactly the same timing.

  Thus, in the present embodiment, each time point from the contraction start time point SS to the expansion end time point DE is set based on the appearance timing of the R wave, and the contraction period and the expansion period are set based on the time points. The set period display 80 visually indicates each time point from the contraction start time point SS to the expansion end time point DE. The set period display 80 and the electrocardiogram waveform display 70 are displayed with their time axes aligned. For this reason, each time point from the contraction start time SS to the expansion end time DE can be visually compared with the electrocardiogram waveform.

  Next, the formation timing of the left screen 60L and the right screen 60R will be described.

  FIG. 4 is a diagram for explaining the formation timing of the left screen 60L and the right screen 60R included in the display image 22 of FIG. Hereinafter, the formation timing of the left and right two screens will be described with reference to FIG. The parts already shown in FIG. 3 are described with the reference numerals in FIG.

  FIG. 4 shows state transitions from the electrocardiogram waveform 90 to the right screen motion image 96R with the horizontal axis as the time axis. Each of the electrocardiogram 90 to the right screen motion image 96R is shown with the time axis aligned.

  The electrocardiogram waveform 90 indicates the appearance timing of the R wave, and the R wave appears in substantially the same cycle over a plurality of heartbeats. The contraction / expansion timing 92 indicates each time point from the contraction start time point SS to the expansion end time point DE. Each point of time from the contraction start point SS to the expansion end point DE is set by the inspector with the R wave as a reference, as described above. In FIG. 4, the contraction start time SS is set to the R wave time. Further, the contraction end time SE and the expansion start time DS are set to the same time. The period from the contraction start time SS to the contraction end time SE is the contraction period of the heart, which is the target tissue, and the period from the expansion start time DS to the expansion end time DE is the expansion period.

  The left screen B mode 94L shows the display state of the B mode image 66 displayed in the left screen 60L, and is a moving image display throughout the period shown in FIG. That is, the B mode image 66 displayed in the left screen 60L always displays the latest image as a moving image over the entire period shown in FIG.

  The left screen motion image 96L indicates the display state of the motion image 62 displayed in the left screen 60L. The image formation period in the left screen motion image 96L corresponds to the contraction period from the contraction start time SS to the contraction end time SE, and within this period, a plurality of time-phase displacement images stage on the B-mode image 66. Thus, the displacement history image (motion image 62) is completed at the time of the contraction end time SE. Then, during the image freeze period in the left screen motion image 96L, that is, the expansion period from the expansion start time DS to the expansion end time DE, the completed displacement history image (motion image 62) is displayed in a frozen state. Incidentally, even when the exercise image 62 is displayed in a frozen state, as described above, the B-mode image 66 in the background continues to display a moving image. However, when the motion image 62 is frozen, the background B-mode image 66 may be frozen.

  The right screen B mode 94R indicates the display state of the B mode image 66 displayed in the right screen 60R. Since the same B mode image 66 is displayed on the right screen 60R and the left screen 60L, the right screen B mode 94R is a moving image display in the entire period shown in FIG. 4 as in the case of the left screen B mode 94L. is there.

  The right screen motion image 96R shows the display state of the motion image 64 displayed in the right screen 60R. The image non-display period in the right screen motion image 96R corresponds to the contraction period from the contraction start time SS to the contraction end time SE. During this period, the motion image 64 is not displayed in the right screen 60R. Only the B mode image 66 is displayed. Then, during the image formation period in the right screen motion image 96R, that is, the expansion period from the expansion start time point DS to the expansion end time point DE, the displacement images of a plurality of time phases are superimposed on the B-mode image 66 step by step. A displacement history image (motion image 64) is completed at the end point DE.

  In the period from the expansion end point DE of the current heartbeat to the contraction start point SS of the next heartbeat, both the motion image 62 during the contraction period of the current heartbeat and the motion image 64 during the expansion period may be displayed in a frozen state. 62 and the motion image 64 may be in a non-display state. However, the motion image 62 and the motion image 64 of the current heartbeat are refreshed and not displayed by the latest heartbeat contraction start time SS (R wave appearance timing) at the latest, and the motion image of the next heartbeat starts from the contraction start time SS of the next heartbeat. The formation of 62 is started.

  As described above, in the period from the appearance timing of the R wave of the current heartbeat to the appearance timing of the R wave of the next heartbeat, the images constituting the left screen 60L and the right screen 60R are formed, and the images are formed over a plurality of heartbeats. The left screen 60L and the right screen 60R are updated for each heartbeat.

  An examiner such as a doctor checks a heartbeat image suitable for diagnosis while viewing the updated image. Then, when a heartbeat image suitable for diagnosis is confirmed, the update of the image is stopped by a freeze switch provided on an operation panel (reference numeral 36 in FIG. 1) or the like. In FIG. 4, a freeze SW 98 indicates the timing when the freeze switch is operated. When the freeze switch is operated, images of a plurality of previous heartbeats from the time of the freeze SW 98 are repeatedly reproduced (loop reproduction). That is, loop reproduction is executed based on data stored in at least one of the two memories (reference numerals 32 and 34 in FIG. 1).

  Incidentally, if the freeze switch is operated during the period from the contraction start time SS of the current heartbeat to the expansion end time DE, even if loop playback is executed using data up to the heartbeat immediately before the current heartbeat. Good. Alternatively, the image formation may be continued until the expansion end point DE of the current heartbeat, and the loop reproduction may be executed using the data up to the current heartbeat.

  As described above, by using the ultrasonic diagnostic apparatus of the present embodiment, an inspector such as a doctor can repeatedly confirm a heartbeat image suitable for diagnosis by loop reproduction. The left screen 60L and the right screen 60R display the motion image 62 during the contraction period and the motion image 64 during the expansion period within the same heartbeat, so that the contraction motion state and the expansion motion state of the heart within the same heartbeat are compared. It becomes possible to observe. For this reason, the ultrasonic diagnostic apparatus of the present embodiment is extremely useful for diagnosis of, for example, myocardial infarction.

  As mentioned above, although preferred embodiment of this invention was described, embodiment mentioned above is only a mere illustration in all the points, and does not limit the scope of the present invention. For example, in the above-described embodiment, the left and right two-screen display mode corresponding to the contraction period and the expansion period within the same heartbeat is shown. However, the plurality of screens corresponding to a plurality of three or more periods within the same heartbeat are They may be displayed side by side vertically. In the above-described embodiment, the display mode of the two-dimensional ultrasonic image is shown. However, the present invention may be applied to a three-dimensional ultrasonic image. Furthermore, in the above-described embodiment, the B mode image is displayed on the background of the motion image, but a Doppler image or the like may be displayed instead of the B mode image.

1 is a block diagram showing an overall configuration of an ultrasonic diagnostic apparatus according to the present invention. It is a schematic diagram which shows a displacement log | history image. It is a figure for demonstrating a display image. It is a figure for demonstrating the formation timing of right-and-left 2 screen.

Explanation of symbols

  16 motion image forming unit, 18 display image forming unit, 22 display image, 62, 64 motion image, 66 B-mode image.

Claims (3)

A transmission / reception unit that transmits / receives ultrasonic waves to / from the heart to acquire echo data;
Based on the echo data, a motion image forming unit that forms a displacement history image by sequentially synthesizing a displacement image indicating the displacement of the heart wall accompanying the contraction and expansion motion with time,
A display image forming unit for forming a display image including a displacement history image;
Have
The motion image forming unit forms a displacement history image of the contraction period and a displacement history image of the expansion period,
The display image forming unit performs a coloring process based on different primary colors on the displacement history image of the contraction period and the displacement history image of the expansion period, and the displacement history image of the contraction period and the displacement of the expansion period within the same heartbeat. Form a display image with history images arranged side by side ,
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 1,
The display image forming unit includes:
A set period display visually indicating a contraction start time indicating the start of the contraction period and a contraction end time indicating the end, an expansion start time indicating the start of the expansion period, and an expansion end time indicating the end;
An electrocardiographic waveform display displaying the electrocardiographic waveform obtained from the heart;
Forming the display image including:
Displaying the set period display and the electrocardiogram waveform display with the time axis aligned with each other;
An ultrasonic diagnostic apparatus. The ultrasonic diagnostic apparatus according to claim 1 or 2 ,
The contraction period and the expansion period are set based on an R wave included in an electrocardiogram obtained from the heart,
The motion image forming unit forms a displacement history image of the contraction period within the set contraction period, and subsequently forms a displacement history image of the expansion period in the set expansion period,
The display image forming unit forms a display image in which a displacement history image in a contraction period and a displacement history image in an expansion period formed in stages are arranged side by side.
An ultrasonic diagnostic apparatus.

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