JP2011087782A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic diagnostic apparatus more accurately recognizing the elasticity of living tissue than ever. <P>SOLUTION: The ultrasonic diagnostic apparatus includes: an elastic image processing part 5 having a physical amount calculating part for calculating the physical amount on the elasticity of each part of the living tissue based on two temporary different echo signals on the same sound ray acquired by transmission/receiving of ultrasonic waves to the living tissue; a display part 7 displaying the elastic image created based on the physical amount; a display control part 6 for controlling the display of the elastic image in the display part 7; a physical amount averaging part 8 for calculating the average of the physical amount for each frame; and a ratio calculating part 9 for calculating the ratio of the value calculated by the physical amount averaging part 8 to a preset average of the physical amount. The display control part 6 does not display the elastic image of an error frame which is determined as not satisfying a prescribed criterion based on the result of comparison by the ratio calculating part 9. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic diagnostic apparatus that displays an elastic image representing the hardness or softness of a living tissue.

  For example, Patent Literature 1 discloses an ultrasonic diagnostic apparatus that synthesizes and displays a normal B-mode image and an elastic image representing the hardness or softness of a living tissue. In this type of ultrasonic diagnostic apparatus, the elasticity image is created as follows. First, ultrasonic waves are transmitted to and received from a living tissue while repeating compression and relaxation from the body surface with an ultrasonic probe, and an echo signal is acquired. Then, based on the obtained echo signal, a physical quantity related to the elasticity of the living tissue is calculated, and the physical quantity is converted into hue information to create a color elastic image. Incidentally, as a physical quantity related to the elasticity of the living tissue, for example, a displacement due to deformation of the living tissue (hereinafter simply referred to as “displacement”) is calculated.

  Explaining a little more about an example of the calculation method of the physical quantity, first, a correlation window having a width corresponding to a predetermined number of data is set for two echo signals on the same sound ray that are temporally different, and correlation calculation is performed between the correlation windows. To calculate the physical quantity. For example, in Patent Document 2, a correlation shift between correlation windows is performed to calculate a waveform shift between both echo signals, and the waveform shift is regarded as a displacement.

JP-A-2005-118152 Japanese Patent Laid-Open No. 2008-126079

  By the way, when changing from the compression operation to the relaxation operation, or vice versa, there may be a moment when neither the compression operation nor the relaxation operation is performed. In addition, when an operator who is not familiar with the operation performs the operation, the compression and the relaxation thereof may be weak. As described above, when the degree of compression or relaxation is insufficient and the deformation of the living tissue is insufficient, the calculated value of the correlation calculation may not appear as a difference corresponding to the difference in elasticity of the living tissue. In this case, the calculated physical quantity does not accurately reflect the elasticity of the living tissue.

  On the other hand, when the degree of compression and relaxation is excessive, lateral displacement may occur in the living tissue. The echo signal acquired in such a case includes noise due to lateral shift, and the correlation coefficient in the correlation calculation may be lowered. Further, if the degree of compression and relaxation is excessive, the deformation of the living tissue is too large, and the correlation window set in the two echo signals cannot be matched and the correlation coefficient may be lowered. Here, if the correlation coefficient in the correlation calculation is low, a physical quantity that accurately reflects the elasticity of the living tissue cannot be obtained.

  In addition, the intensity of the echo signal is insufficient in a region where there are few ultrasonic reflectors or in a deep part of a living tissue where transmitted ultrasonic waves are difficult to reach due to attenuation. Thus, the correlation coefficient of the correlation calculation for an echo signal with insufficient signal strength is low. In addition, when the direction of the compression and relaxation of the ultrasonic probe do not coincide with the direction of the sound ray of the ultrasonic wave, the above-described lateral shift occurs, and therefore the phase of correlation calculation for the echo signal acquired in such a state The number of relationships is also low. Therefore, even in these cases, a physical quantity that accurately reflects the elasticity of the living tissue cannot be obtained.

  As described above, a physical quantity that does not accurately reflect the elasticity of the living tissue is obtained, and the elasticity image created based on such a physical quantity is not an image that reflects the elasticity of the actual living tissue. Therefore, there is a possibility that the elasticity of the living tissue cannot be accurately grasped.

  The problem to be solved by the present invention is to provide an ultrasonic diagnostic apparatus capable of grasping the elasticity of living tissue more accurately than before.

  The present invention has been made to solve the above-mentioned problems. The invention according to the first aspect provides a correlation window for two echo signals different in time on the same sound ray obtained by transmitting and receiving ultrasonic waves to a living tissue. And a physical quantity calculation unit that calculates a physical quantity related to elasticity of each part in the living tissue by performing a correlation operation between the correlation windows, and based on the physical quantity, the elasticity image data of the living tissue is transmitted on an ultrasound transmission / reception surface. An elastic image data creation unit that creates an elastic image creation region, a display unit that displays an elastic image based on the elastic image data, a display control unit that controls display of an elastic image on the display unit, and the elastic image creation region The physical quantity average part for calculating the average of the physical quantity for each frame, and the calculated value by the physical quantity average part A comparison unit that compares with a value, and the display control unit does not display an elastic image of an error frame that is determined not to satisfy a predetermined criterion based on a comparison result by the comparison unit. This is a sonic diagnostic apparatus.

  According to the invention of the second aspect, in the invention of the first aspect, the physical quantity averaging unit calculates the average of the physical quantities obtained for the correlation window in which the correlation calculation of the correlation coefficient equal to or greater than a predetermined threshold is performed. This is an ultrasonic diagnostic apparatus.

  According to a third aspect of the invention, in the first or second aspect of the invention, the comparison unit calculates, as the comparison result, a ratio of a value calculated by the physical quantity average unit to a preset average value of the physical quantity. This is an ultrasonic diagnostic apparatus.

  A fourth aspect of the invention is an ultrasonic diagnostic apparatus according to any one of the first to third aspects of the invention, further comprising a notification unit that notifies a comparison result by the comparison unit.

  The invention of the fifth aspect sets a correlation window for two echo signals different in time on the same sound ray obtained by transmission / reception of ultrasonic waves to / from a living tissue, and performs a correlation calculation between the correlation windows to thereby calculate the living tissue A physical quantity calculation unit that calculates a physical quantity relating to elasticity of each part in the apparatus; an elastic image data creation unit that creates elasticity image data of a living tissue based on the physical quantity for an elastic image creation region on an ultrasound transmission / reception surface; and the elasticity A display unit that displays an elastic image based on image data; a display control unit that controls display of the elastic image on the display unit; and an average of the correlation coefficient in the correlation calculation between the correlation windows in the elastic image creation region is framed A correlation coefficient averaging unit calculated for each, and the display control unit determines a predetermined value based on a calculation result of the correlation coefficient averaging unit. An ultrasonic diagnostic apparatus characterized by not displaying the elastic image of the error frame is determined not to satisfy the criteria.

  A sixth aspect of the invention is the ultrasonic diagnostic apparatus according to the fifth aspect of the invention, further comprising a notifying unit for notifying a calculation result by the correlation coefficient averaging unit.

  According to the seventh aspect of the invention, a correlation window is set in two temporally different echo signals on the same sound ray obtained by transmitting / receiving ultrasonic waves to / from a biological tissue, and a correlation calculation is performed between the correlation windows to perform biological tissue A physical quantity calculation unit that calculates a physical quantity relating to elasticity of each part in the apparatus; an elastic image data creation unit that creates elasticity image data of a living tissue based on the physical quantity for an elastic image creation region on an ultrasound transmission / reception surface; and the elasticity Obtained for a display unit that displays an elastic image based on image data, a display control unit that controls the display of the elastic image on the display unit, and a correlation window in which a correlation calculation of a correlation coefficient equal to or greater than a predetermined threshold is performed. A physical quantity average unit that calculates an average of the physical quantity in the elastic image creation region for each frame, and a preset average value of the physical quantity A ratio calculation unit that calculates a ratio of calculated values by the physical quantity average unit; a correlation coefficient average unit that calculates an average of the correlation coefficient in the correlation image between the correlation windows in the elastic image creation region; and A multiplication unit that multiplies the calculation value of the ratio calculation unit and the calculation value of the correlation coefficient averaging unit, and the display control unit must satisfy a predetermined criterion based on the calculation result of the multiplication unit An ultrasonic diagnostic apparatus that does not display an elastic image of a determined error frame.

  According to an eighth aspect of the invention, in the seventh aspect of the invention, the multiplication unit performs a weighting operation on the calculated value of the ratio calculating unit and the calculated value of the correlation coefficient averaging unit. This is an ultrasonic diagnostic apparatus.

  A ninth aspect of the invention is the ultrasonic diagnostic apparatus according to the seventh or eighth aspect of the invention, further comprising a notifying unit for notifying a multiplication result by the multiplying unit.

  The invention according to the tenth aspect sets a correlation window to two temporally different echo signals on the same sound ray obtained by transmitting / receiving ultrasonic waves to / from a biological tissue, and performs a correlation calculation between the correlation windows to perform the biological tissue A physical quantity calculation unit that calculates a physical quantity relating to elasticity of each part in the apparatus; an elastic image data creation unit that creates elasticity image data of a living tissue based on the physical quantity for an elastic image creation region on an ultrasound transmission / reception surface; and the elasticity Obtained for a display unit that displays an elastic image based on image data, a display control unit that controls the display of the elastic image on the display unit, and a correlation window in which a correlation calculation of a correlation coefficient equal to or greater than a predetermined threshold is performed. A physical quantity average unit that calculates an average of the physical quantity in the elastic image creation region for each frame, and a preset average value of the physical quantity A ratio calculation unit that calculates a ratio of calculated values by the physical quantity average unit, a correlation coefficient average unit that calculates an average in the elastic image creation region of a correlation coefficient in a correlation calculation between the correlation windows, and A multiplication unit that multiplies the calculation value of the ratio calculation unit and the calculation value of the correlation coefficient average unit, the calculation result of the ratio calculation unit, the calculation result of the correlation coefficient average unit, or the calculation result of the multiplication unit An operation unit that inputs an instruction for selecting any of the errors, and the display control unit is determined to not satisfy a predetermined criterion based on a calculation result selected by the operation unit An ultrasonic diagnostic apparatus that does not display an elastic image of a frame.

  The invention according to an eleventh aspect is the invention according to the tenth aspect, wherein the operation unit is selected from the calculation result of the ratio calculation unit, the calculation result of the correlation coefficient average unit, or the calculation result of the multiplication unit. An ultrasonic diagnostic apparatus including a notification unit that notifies a calculation result.

  The invention of the twelfth aspect sets a correlation window to two temporally different echo signals on the same sound ray obtained by transmitting / receiving ultrasonic waves to / from a biological tissue, and performs a correlation calculation between the correlation windows to perform the biological tissue A physical quantity calculation unit that calculates a physical quantity relating to elasticity of each part in the apparatus; an elastic image data creation unit that creates elasticity image data of a living tissue based on the physical quantity for an elastic image creation region on an ultrasound transmission / reception surface; and the elasticity Obtained for a display unit that displays an elastic image based on image data, a display control unit that controls the display of the elastic image on the display unit, and a correlation window in which a correlation calculation of a correlation coefficient equal to or greater than a predetermined threshold is performed. A physical quantity average unit that calculates an average of the physical quantity in the elastic image creation region for each frame, and a preset average value of the physical quantity A ratio calculation unit that calculates a ratio of calculated values by the physical quantity average unit, a correlation coefficient average unit that calculates an average in the elastic image creation region of a correlation coefficient in a correlation calculation between the correlation windows, and And the display control unit does not display an elastic image of an error frame determined not to satisfy a predetermined criterion based on a calculation result of the ratio calculation unit and a calculation result of the correlation coefficient average unit. This is an ultrasonic diagnostic apparatus.

  The thirteenth aspect of the invention is the ultrasonic wave according to the twelfth aspect of the invention, further comprising a notifying unit for notifying either of the calculation result of the ratio calculation unit or the calculation result of the correlation coefficient average unit. It is a diagnostic device.

  According to a fourteenth aspect, in the twelfth aspect, the multiplication unit that multiplies the calculation value of the ratio calculation unit and the calculation value of the correlation coefficient average unit, and the calculation result of the multiplication unit is notified. An ultrasonic diagnostic apparatus comprising:

  The invention of the fifteenth aspect sets a correlation window for two temporally different echo signals on the same sound ray obtained by transmitting and receiving ultrasonic waves while performing compression and relaxation on a living tissue, and between the correlation windows The physical quantity calculation unit calculates the physical quantity related to the elasticity of each part in the living tissue with the positive and negative signs corresponding to the compression and the relaxation, and the elasticity image data of the living tissue based on the physical quantity. An elastic image data generating unit for generating an elastic image generating region on the ultrasonic transmission / reception surface; a display unit for displaying an elastic image based on the elastic image data; and a display control unit for controlling display of the elastic image on the display unit And the display control unit detects an error frame that is determined not to satisfy a predetermined criterion based on a ratio of the positive and negative signs in one frame. An ultrasonic diagnostic apparatus characterized by not displaying an image.

  The invention according to the sixteenth aspect sets a correlation window to two temporally different echo signals on the same sound ray obtained by transmitting / receiving ultrasonic waves to / from a biological tissue, and performs a correlation calculation between the correlation windows to perform the biological tissue A physical quantity calculation unit that calculates a physical quantity relating to elasticity of each part in the apparatus; an elastic image data creation unit that creates elasticity image data of a living tissue based on the physical quantity for an elastic image creation region on an ultrasound transmission / reception surface; and the elasticity An error frame that includes a display unit that displays an elastic image based on image data, and a display control unit that controls display of the elastic image on the display unit, wherein the display control unit is determined not to satisfy a predetermined criterion An ultrasonic diagnostic apparatus that displays a predetermined alternative elastic image instead of the elastic image.

  According to a seventeenth aspect, in the sixteenth aspect, the alternative elastic image is an elastic image created by weighting and adding elastic image data for several frames before the error frame. This is an ultrasonic diagnostic apparatus.

  According to an eighteenth aspect, in the invention according to the sixteenth aspect, the alternative elastic image weights the elastic image data displayed in the immediately preceding frame and the elastic image data of the latest frame that is not the error frame. An ultrasonic diagnostic apparatus characterized by being an elastic image created by addition processing.

  According to a nineteenth aspect, in the sixteenth aspect, the elasticity image data displayed in the immediately preceding frame is weighted and added to the elasticity image data of the past several frames not including the elasticity image data of the error frame. The ultrasonic diagnostic apparatus is characterized by being data obtained by processing.

  In a twentieth aspect according to the sixteenth aspect, in the sixteenth aspect, the alternative elastic image is an elastic image created by performing weighted addition processing on the elastic image data of the error frame and the elastic image data before the error frame. This is an ultrasonic diagnostic apparatus.

  A twenty-first aspect of the invention is the ultrasonic diagnostic apparatus according to the sixteenth aspect of the invention, wherein the alternative elastic image is an elastic image of a frame displayed immediately before the error frame.

  According to the present invention, an error frame that does not satisfy a predetermined criterion based on a comparison result obtained by comparing an average value in the elastic image creation region of a physical quantity of each part in the living tissue and a preset average value of the physical quantity. The elastic image of is not displayed. Here, when the pressure on the living tissue and the degree of relaxation thereof are insufficient or excessive, it is reflected in the comparison result. Therefore, by not displaying the elastic image of the error frame that does not satisfy the predetermined criterion based on the comparison result, it is possible to display only the elastic image that more accurately reflects the elasticity of the living tissue. Thereby, the elasticity of a biological tissue can be grasped | ascertained more correctly than before.

  In addition, the average value of the physical quantity obtained for the correlation window in which the correlation calculation of the correlation coefficient equal to or greater than the predetermined threshold is performed by the physical quantity averaging unit is a part where the intensity of the echo signal is insufficient, or the lateral deviation of the living tissue This is an average value obtained by removing the displacement of a portion having a low correlation coefficient, such as a generated portion. Therefore, the comparison result between such an average value and the preset average value of the physical quantity indicates more accurately whether or not the pressure on the living tissue and the relaxation thereof are performed with an appropriate strength. . As described above, it is acquired in a state where the compression and the relaxation to the living tissue are performed with an appropriate strength by preventing the elastic image of the error frame not satisfying the predetermined criterion from being displayed based on the comparison result. Only the elastic image based on the echo signal can be displayed more reliably.

  According to another invention, an average of the correlation coefficient in the correlation image between the correlation windows in the elastic image creation area is calculated, and an elastic image of an error frame that does not satisfy a predetermined criterion is calculated based on the calculation result. Do not show. Here, for example, if the compression and relaxation of the living tissue is excessive or the intensity of the echo signal is insufficient, the average of the correlation coefficient is low. Therefore, by not displaying the elastic image of the error frame that does not satisfy the predetermined criterion based on the average of the correlation coefficient, it is possible to display only the elastic image that more accurately reflects the elasticity of the living tissue. Thereby, the elasticity of a biological tissue can be grasped | ascertained more correctly than before.

  According to another invention, a calculated value calculated by the ratio calculating unit using an average value of physical quantities obtained for a correlation window in which a correlation calculation of a correlation coefficient equal to or greater than a predetermined threshold is performed; The calculated value calculated by the correlation coefficient averaging unit is multiplied by the multiplication unit, and an elastic image of an error frame that does not satisfy a predetermined criterion is not displayed based on the calculation result. Here, the calculation result obtained by the multiplication is obtained by adding an element of the degree of compression and relaxation to the living tissue and an element of the correlation coefficient. Accordingly, since an elastic image of an error frame that does not satisfy a predetermined criterion is not displayed based on such a calculation result, only an elastic image that more accurately reflects the elasticity of the living tissue can be displayed, and the elasticity of the living tissue can be displayed. Can be grasped more accurately than before.

  According to another invention, an error that does not satisfy a predetermined criterion based on a calculation result selected from a calculation result of the ratio calculation unit, a calculation result of the correlation coefficient averaging unit, or a calculation result of the multiplication unit Since the elasticity image of the frame is not displayed, it is possible to display only the elasticity image that more accurately reflects the elasticity of the living tissue. In addition, since the calculation result of the ratio calculation unit, the calculation result of the correlation coefficient average unit, or the calculation result of the multiplication unit can be selected, it is determined based on different criteria whether or not the frame corresponds to an error frame. And a more appropriate elastic image can be displayed.

  According to another invention, the elasticity image of the error frame that does not satisfy a predetermined criterion is not displayed based on the calculation result of the ratio calculation unit and the calculation result of the correlation coefficient average unit, so that the elasticity of the living tissue is reduced. The display of only the elastic image reflected more accurately can be made more reliable.

  In addition, according to another invention, an elastic image of an error frame that does not satisfy a predetermined criterion is not displayed based on a ratio of positive and negative signs according to compression on the living tissue and its relaxation. Here, when the compression and the relaxation are appropriately performed, the proportion of the same sign is high in the physical quantity in one frame. On the other hand, if the compression and the relaxation are not properly performed, the physical quantities in one frame are not biased to the same sign. Accordingly, only the elasticity image that more accurately reflects the elasticity of the living tissue can be displayed by not displaying the elasticity image of the error frame that does not satisfy the predetermined criterion based on the ratio of the positive and negative signs in one frame. Can do.

  Further, according to another invention, by displaying a predetermined alternative elastic image instead of the elastic image of the error frame, the elastic image reflecting the elasticity of the living tissue is displayed more accurately, and the elastic image is not displayed. It is possible to prevent intermittent elastic image display due to the presence of the frame.

1 is a block diagram showing a schematic configuration of a first embodiment of an ultrasonic diagnostic apparatus according to the present invention. It is a block diagram which shows a part of structure in the ultrasound diagnosing device shown in FIG. It is explanatory drawing of preparation of B mode image data and elasticity image data. It is a figure which shows an example of the display of the display part in the ultrasonic diagnosing device shown in FIG. It is a figure for demonstrating calculation of the physical quantity at the time of creating elasticity image data. It is a figure which shows the graph of the function used in a ratio calculation part. It is a figure which shows the display part in which the ultrasonic image which consists only of B mode images was displayed in the error frame. It is explanatory drawing of the 1st modification of 1st embodiment. In the 1st modification of 1st embodiment, it is explanatory drawing in case the flame | frame F4 is not an error frame. In the 1st modification of 1st embodiment, it is explanatory drawing in case the flame | frame F4 is an error frame. In the 1st modification of 1st embodiment, it is a figure for demonstrating the other example of the production method of an alternative elastic image. It is a block diagram which shows schematic structure of the 2nd modification of 1st embodiment. It is a figure which shows the display part on which the quality display was displayed. It is a figure for demonstrating an example of the display of a display part, and explaining that a quality display is displayed so that it may flow from left to right with progress of time. It is a figure for demonstrating an example of the display of a display part, and explaining that a quality display is displayed so that it may flow from left to right with progress of time. It is a figure for demonstrating an example of the display of a display part, and explaining that a quality display is displayed so that it may flow from left to right with progress of time. It is a figure which shows an example of the display of a display part, and shows the other example of a quality display. It is a block diagram which shows schematic structure of 2nd embodiment of the ultrasonic diagnosing device which concerns on this invention. FIG. 19 is a block diagram illustrating a partial configuration of the ultrasonic diagnostic apparatus illustrated in FIG. 18. It is a block diagram which shows schematic structure of the ultrasound diagnosing device in the modification of 2nd embodiment. It is a block diagram which shows schematic structure of 3rd embodiment of the ultrasonic diagnosing device which concerns on this invention. It is a block diagram which shows a part of structure in the ultrasound diagnosing device shown in FIG. It is a block diagram which shows schematic structure of the ultrasonic diagnosing device in the modification of 3rd embodiment. It is a block diagram which shows schematic structure of 4th embodiment of the ultrasonic diagnosing device which concerns on this invention. FIG. 25 is a block diagram showing a partial configuration of the ultrasonic diagnostic apparatus shown in FIG. 24. It is a block diagram which shows schematic structure of the ultrasonic diagnosing device in the modification of 4th embodiment. It is a block diagram which shows schematic structure of 5th embodiment of the ultrasonic diagnosing device which concerns on this invention. It is a block diagram which shows schematic structure of 6th embodiment of the ultrasonic diagnosing device which concerns on this invention. It is a block diagram which shows the structure of the elasticity image process part in the ultrasonic diagnosing device shown in FIG. It is a figure which shows the other example of a quality display. It is a figure which shows the display part on which the other example of the quality display was displayed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
First, a first embodiment will be described with reference to FIGS. An ultrasonic diagnostic apparatus 1 shown in FIG. 1 includes an ultrasonic probe 2, a transmission / reception unit 3, a B-mode image processing unit 4, an elastic image processing unit 5, a display control unit 6, a display unit 7, a physical quantity averaging unit 8, and a ratio calculation unit. 9, and further includes a control unit 10 and an operation unit 11.

  The ultrasonic probe 2 transmits an ultrasonic wave to a living tissue and receives an echo thereof. An elastic image is created as described below based on echo signals acquired by transmitting and receiving ultrasonic waves while repeating compression and relaxation while the ultrasonic probe 2 is in contact with the surface of the living tissue.

  The transmission / reception unit 3 drives the ultrasonic probe 2 under a predetermined scanning condition to perform ultrasonic scanning for each sound ray. Further, the echo signal received by the ultrasonic probe 2 is subjected to signal processing such as phasing addition processing. The echo signal signal-processed by the transmission / reception unit 3 is output to the B-mode image processing unit 4 and the elastic image processing unit 5.

  Incidentally, the transmission / reception unit 3 separately performs scanning for creating a B-mode image and scanning for creating an elastic image. As scanning for creating an elastic image, scanning is performed twice on the same sound ray in a region where an elastic image is created in the subject.

  The B-mode image processing unit 4 performs B-mode processing such as logarithmic compression processing and envelope detection processing on the echo signal output from the transmission / reception unit 3 to create B-mode data. Based on the above, B-mode image data having luminance information corresponding to the intensity of the echo signal is created.

  Here, the B mode data after the B mode processing may be stored as raw data in a storage unit (not shown). The B-mode image processing unit 4 may create the B-mode image data based on the B-mode data stored in the storage unit.

  The elastic image processing unit 5 creates elastic image data based on the echo signal output from the transmission / reception unit 3. More specifically, the elastic image processing unit 5 includes a physical quantity calculating unit 51 and an elastic image data creating unit 52 as shown in FIG. The physical quantity calculation unit 51 calculates a displacement (hereinafter, simply referred to as “displacement”) due to deformation of each part in the biological tissue caused by the compression and relaxation by the ultrasonic probe 2 as a physical quantity related to the elasticity of each part in the biological tissue. To do. The physical quantity calculator 51 calculates a displacement for each pixel based on two echo signals on the same sound ray belonging to two temporally different frames (i) and (ii) as shown in FIG. More specifically, the physical quantity calculation unit 51 sets correlation windows W1 and W2 in the echo signal as will be described later (see FIG. 5), and performs a correlation operation between the correlation windows W1 and W2 to change the displacement. calculate. Based on the displacement data, the elastic image data generating unit 52 generates elastic image data for one pixel. The physical quantity calculator 51 is an example of an embodiment of a physical quantity calculator in the present invention.

  Here, the displacement calculated by the physical quantity calculation unit 51 is calculated with a positive / negative sign corresponding to the pressure on the living tissue and its relaxation. For example, a negative sign displacement is mainly calculated during compression, and a positive sign displacement is calculated during relaxation.

  The elasticity image data creation unit 52 converts the displacement calculated by the physical quantity calculation unit 51 into hue information, and an elasticity image for an elasticity image creation region (a region of interest R described later in this example) on the ultrasound transmission / reception surface. Create data. The elastic image data creation unit 52 is an example of an embodiment of the elastic image data creation unit in the present invention.

  Incidentally, as shown in FIG. 3, elastic image data for one frame is created from echo signals belonging to two different frames (i) and (ii). On the other hand, the B-mode image data is created from the echo signal of any of the frames (i) and (ii).

  In this example, as shown in FIG. 4, a region of interest (ROI) R is set on the B-mode image BG displayed on the display unit 7, and the elastic image data is generated for the region of interest R. The The region of interest R is an example of an embodiment of an elastic image creation region in the present invention. However, the present invention is not limited to the case where the elastic image is generated for a part of the B-mode image BG as described above, and the elastic image data may be generated for the entire B-mode image BG.

  Here, the displacement data obtained by the physical quantity calculation unit 51 may be stored as raw data in a storage unit (not shown). The elastic image data creation unit 52 may create elastic image data based on the displacement data stored in the storage unit.

  The B-mode image data created by the B-mode image processing unit 4 and the elasticity image data created by the elasticity image processing unit 5 are combined by the display control unit 6. Specifically, the display control unit 6 adds the B-mode image data for one frame and the elastic image data, and creates ultrasonic image data for one frame to be displayed on the display unit 7. . The display control unit 6 causes the display unit 7 to display an ultrasonic image G based on the obtained ultrasonic image data. The ultrasonic image G is an image in which a black and white B-mode image BG and a color elastic image EG are combined as shown in FIG. In this example, the elastic image EG is displayed translucently in the region of interest R (with the background B-mode image transparent). The display control unit 6 is an example of an embodiment of a display control unit in the present invention, and the display unit 7 is an example of an embodiment of a display unit in the present invention.

  However, the display control unit 6 does not display the elastic image EG of the error frame determined not to satisfy the predetermined standard based on the calculated value Y calculated by the ratio calculation unit 9 as described later. In this case, the display control unit 6 does not synthesize the B-mode image data and the elasticity image data, and displays an ultrasonic image including only the B-mode image BG (see FIG. 7). Details will be described later.

The physical quantity averaging unit 8 calculates the average of the displacement calculated for each pixel in the region of interest R for each frame. An average value Xr _AV calculated value of the physical quantity average unit 8. The physical quantity average unit 8 is an example of an embodiment of a physical quantity average unit in the present invention.

The ratio calculation unit 9 calculates a ratio Ra of the average value Xr _{AV to} the average ideal value Xi _AV of displacement, and further performs an operation of (Equation 1) as described later. The ratio calculation unit 9 is an example of an embodiment of a comparison unit and a ratio calculation unit in the present invention. The ideal value Xi _AV is an example of an embodiment of an average value of preset physical quantities in the present invention.

Here, the ideal value Xi _AV is a strength capable of obtaining an elastic image more accurately reflecting the elasticity of the living tissue, and the ultrasonic probe 2 compresses and relaxes the ultrasound when transmitting and receiving the ultrasound. Is an average value of displacements obtained in an arbitrarily set region. This ideal value Xi _AV is an experimentally obtained value obtained by conducting an experiment on a phantom composed of a part having the same hardness as a tumor or a part having the same hardness as a normal tissue. In addition, the ideal value Xi _AV may be set by the operator in the operation unit 11 or may be stored in the apparatus as a default.

  The control unit 10 is constituted by a CPU (Central Processing Unit), reads a control program stored in a storage unit (not shown), and executes functions in each unit of the ultrasonic diagnostic apparatus 1. The operation unit 11 includes a keyboard and a pointing device (not shown) for an operator to input instructions and information.

  Now, the operation of the ultrasonic diagnostic apparatus 1 of this example will be described. First, the transmission / reception unit 3 transmits an ultrasonic wave from the ultrasonic probe 2 to a living tissue of a subject and acquires an echo signal thereof. At this time, the ultrasonic probe 2 transmits and receives ultrasonic waves while repeatedly pressing and relaxing the subject.

  Then, the B-mode image processing unit 4 creates B-mode image data based on the echo signal. The elastic image processing unit 5 creates elastic image data based on the echo signal. The B-mode image data and the elastic image data are synthesized by the display control unit 6, and an ultrasonic image G obtained by synthesizing the B-mode image BG and the elastic image EG as shown in FIG. Is displayed. However, the elastic image EG of the error frame is not displayed.

  The creation of elasticity image data and the display of the elasticity image EG in the elasticity image processing unit 5 will be described in detail. In creating the elasticity image data, the physical quantity calculation unit 51 sets a correlation window for each echo signal belonging to frames (i) and (ii). Specifically, as shown in FIG. 5, the physical quantity calculation unit 51 sets a correlation window W1 for echo signals belonging to the frame (i), and sets a correlation window W2 for echo signals belonging to the frame (ii). These correlation windows W1 and W2 correspond to position pixels. The physical quantity calculator 51 calculates a displacement by performing a correlation operation between the correlation windows W1 and W2.

  More specifically, in FIG. 5, the frames (i) and (ii) are made up of echo signals acquired on a plurality of sound rays. In FIG. 5, five sound lines L1a, L1b, L1c, L1d, and L1e are shown as a part of the plurality of sound lines in the frame (i), and the sound lines L1a to L1e in the frame (ii) are shown. As sound lines corresponding to L1e, sound lines L2a, L2b, L2c, L2d, and L2e are shown. That is, the sound ray L1a and the sound ray L2a, the sound ray L1b and the sound ray L2b, the sound ray L1c and the sound ray L2c, the sound ray L1d and the sound ray L2d, the sound ray L1e and the sound ray. L2e corresponds to the same sound ray belonging to two different frames. In FIG. 5, R (i) and R (ii) indicate regions corresponding to the region of interest R.

  For example, it is assumed that a correlation window W1c is set as the correlation window W1 in the echo signal on the sound ray L1c, and a correlation window W2c is set as the correlation window W2 in the echo signal on the sound ray L2c. The physical quantity calculation unit 51 performs a correlation calculation between the correlation windows W1c and W2c to calculate a displacement. The physical quantity calculator 51 sequentially sets correlation windows W1c and W2c from the upper end 100 to the lower end 101 of the regions R (i) and R (ii) on the sound rays L1c and L2c, and calculates the displacement. Further, the physical quantity calculation unit 51 calculates the displacement in the same manner for other sound rays in the regions R (i) and R (ii). When the displacement is calculated by the physical quantity calculation unit 51 in this way, the elasticity image data creation unit 52 creates elasticity image data based on the displacement.

Next, display of the elastic image EG will be described. The display control unit 6 does not display the elastic image EG of the error frame that is determined not to satisfy the predetermined criterion based on the calculated value Y of the ratio calculation unit 9. In detail, first, the physical quantity average unit 8, the region of interest R and calculates an average value _{Xr AV} displacement in (the region R (i), R (ii )). Incidentally, the displacement from the sometimes becomes negative, the average value Xr _AV is also that there shall be negative. Next, the ratio calculation unit 9 calculates Xr _AV / Xi _AV to calculate the ratio Ra. Further, the ratio calculation unit 9 substitutes the ratio Ra into the following (Expression 1) to obtain a numerical value Y.
Y = 1.0− | log ₁₀ | Ra || (Expression 1)
Here, Y is a calculated value obtained for each frame. This calculated value Y is an example of an embodiment of the comparison result by the comparison unit and the calculated value of the ratio calculation unit in the present invention.

Incidentally, the equation (1) is intended for the ratio Ra in the range from 0 to 1, Y obtained by the equation (1), the ratio of the average value _{Xr AV} for the ideal value _{Xi AV} Is equivalent to When the function represented by (Equation 1) is represented by a graph, the graph shown in FIG. 6 is obtained. As shown in FIG. 6, 0 ≦ Y ≦ 1.

  Further, it is assumed that 0.1 ≦ | Ra | ≦ 10, and when | Ra | exceeds this range, Y is set to zero.

  The calculated value Y of the ratio calculator 9 is a numerical value representing the quality of the elastic image. The closer the calculated value Y is to 1, the better the quality of the elastic image is. On the other hand, the closer the calculated value Y is to 0, the worse the quality of the elastic image is. Here, a good elasticity image means that the elasticity image reflects the elasticity of the living tissue more accurately, while a poor elasticity image means that the elasticity of the living tissue is accurate. This means that the elastic image is not reflected in the image.

The relationship between the calculated value Y and the quality of the elastic image will be described in more detail. As can be seen from the graph of FIG. 6, when the average value Xr _AV is equal to the ideal value Xi _AV (that is, | Ra | is 1). The calculated value Y is 1. Therefore, if the calculated value Y is 1 or a value close to 1, the degree of compression and relaxation of the living tissue by the ultrasonic probe 2 is appropriate, and an elasticity image EG that accurately reflects the elasticity of the living tissue is obtained. It has been obtained.

On the other hand, the calculated value Y approaches zero as the average value Xr _AV becomes farther from the ideal value Xi _AV (ie, as | Ra | becomes farther from 1). Here, the fact that the average value Xr _AV is a value that is separated from the ideal value Xi _AV means that the degree to which the ultrasonic probe 2 compresses or relaxes the living tissue is insufficient or excessive. To do. Therefore, as the calculated value Y approaches zero, the degree of compression or relaxation on the living tissue is insufficient, or as a result, the elasticity image EG that accurately reflects the elasticity of the living tissue is not obtained. Become.

The calculated value Y is input to the display control unit 6. The display control unit 6 does not cause the display unit 7 to display an elastic image EG of an error frame that is determined not to satisfy a predetermined criterion based on the calculated value Y. Specifically, the display control unit 6, the frame calculation value Y is equal to or less than the threshold Y _TH is determined error frame does not satisfy the predetermined criteria, not displaying the elastic image EG.

Here, if the elastic image EG of the error frame whose calculated value Y is equal to or less than the threshold value Y _TH is not displayed, the ultrasonic image G consisting only of the B-mode image BG is displayed in the error frame as shown in FIG. It means that. Therefore, for the error frame, the display control unit 6 does not synthesize the B-mode image data and the elastic image data, and displays the B-mode image data as it is as the B-mode image BG.

The threshold value _YTH will be described. Since 0 ≦ Y ≦ 1, the threshold value Y _TH is also set in the range of 0 to 1. If the threshold Y _TH is too high, only the elastic image EG that reflects the elasticity of the living tissue can be displayed as accurately as possible, but the frame rate of the elastic image EG may be too low. On the other hand, if the threshold value _YTH is too low, the frame rate of the elastic image EG is good, but the ratio at which the elastic image EG that does not accurately reflect the elasticity of the living tissue is displayed becomes high. Therefore, the threshold value _YTH is set to a value that can display the elasticity image EG that accurately reflects the elasticity of the living tissue to some degree so that the frame rate does not decrease too much.

The threshold value Y _TH may be stored in advance in a storage unit (not shown) or may be set by inputting in the operation unit 11.

According to the ultrasonic diagnostic apparatus 1 of this example, an elastic image EG of an error frame in which the calculated value Y calculated based on the ratio Ra of the average value Xr _AV to the ideal value Xi _AV is equal to or less than a predetermined threshold Y _TH. Is not displayed. Therefore, the elastic image EG based on the echo signal acquired in a state where the pressure on the living tissue and the degree of relaxation thereof are insufficient or excessive are not displayed. Thereby, since only the high-quality elastic image EG can be displayed, the elasticity of the living tissue can be grasped more accurately than before.

  Next, a modification of the first embodiment will be described. First, the first modification will be described. In this first modification, a complementary process for displaying an alternative elastic image instead of the elastic image EG of the error frame may be performed. This will be specifically described. As shown in FIG. 8, when the ultrasonic image G based on the ultrasonic image data D1, D2, and D3 for the frames F1, F2, and F3 is displayed in the past, and then the ultrasonic image G of the frame F4 is displayed. Will be described as an example. Incidentally, the ultrasonic image data D1 is composed of B mode image data BD1 and elastic image data ED1, the ultrasonic image data D2 is composed of B mode image data BD2 and elastic image data ED2, and the ultrasonic image data D3 is B. It consists of mode image data BD3 and elastic image data ED3.

The B-mode image data and elasticity image data obtained for the frame F4 are referred to as B-mode image data BD4 and elasticity image data ED4. When the calculated value Y of the ratio calculation unit 9 for the frame F4 exceeds the threshold _YTH , that is, when the frame F4 is not an error frame, the display control unit 6 displays the B-mode data as shown in FIG. The ultrasonic image data D4 is created by combining the BD4 and the elastic image data ED4, and the ultrasonic image G based on the ultrasonic image data D4 is displayed.

On the other hand, when the calculated value Y of the ratio calculation unit 9 for the frame F4 is equal to or less than the threshold value _YTH , that is, when the frame F4 is an error frame, the frames F1, F2, and F3 displayed before the frame F4 are displayed. An alternative elastic image obtained by weighting and adding the elastic images is displayed.

  The weighted addition process will be described in more detail. As shown in FIG. 10, the display control unit 6 weights and adds the elastic image data ED1, ED2, and ED3 for the frames F1, F2, and F3 to generate elastic image data ED4 ′. That is, the display control unit 6 weights and adds the corresponding pixel values in the elastic image data ED1, ED2, and ED3, and creates elastic image data ED4 'composed of the obtained pixel values. However, as weighted addition processing, the elasticity data of the frames F1, F2, and F3 obtained by the physical quantity calculation unit 51 is weighted and added to the displacement of the corresponding pixel, and the data including the obtained displacement is used as the elasticity image data creation unit. The elastic image data ED4 'may be created by converting the color information into hue information 52. That is, it is assumed that the weighting addition process for the elasticity image data in the present invention includes the weighting addition process for the elasticity data obtained by the physical quantity calculation unit 51.

  The weighting coefficients used in the weighted addition process may be equal in the frames F1, F2, and F3, or may be different.

  The display control unit 6 synthesizes the obtained elastic image data ED4 ′ and B-mode image data BD4 to create ultrasonic image data D4, and displays an ultrasonic image G based on the ultrasonic image data D4. . Thereby, instead of the elasticity image based on the elasticity image data ED4, the elasticity image based on the elasticity image data ED4 ′ is displayed as a substitute elasticity image. The elastic image based on the elastic image data ED4 ′ is an example of an embodiment of a predetermined alternative elastic image in the present invention.

The elastic image EG is based on the elastic image data ED4 ', is calculated value Y is obtained by weighting addition processing of data of the elastic image EG in the frame F1~F3 displayed as exceeds the threshold value Y _TH data Therefore, the elastic image having elasticity image equivalent quality of calculated value Y is obtained which exceeds the threshold value Y _TH. Accordingly, it is possible to always display a high-quality elastic image EG and to eliminate the frame in which the elastic image EG is not displayed, thereby preventing intermittent elastic image EG from being displayed.

However, the display control unit 6, when an error frame calculation value Y is equal to or less than the threshold Y _TH are continuous predetermined number, it may not display the substitute elasticity image discontinue complementary processing.

  Note that the weighted addition process including the frame F4 that is an error frame, that is, the weighted addition process may be performed on the frames F1 to F4.

  The alternative elastic image may be an elastic image of the frame F3 displayed immediately before the frame F4 that is an error frame.

  The creation of the alternative elastic image is not limited to the above-described method. Another example of the alternative elastic image creation method will be described with reference to FIG.

  In frames F1 to F5 shown in FIG. 11, frames F1 to F3 are not error frames, and frames F4 and F5 are error frames. In the frames F1 to F5, an ultrasound image G based on the ultrasound image data D1 to D5 is displayed. The ultrasonic image data D1 includes B-mode image data BD1 and display elastic image data ED1d, and the ultrasonic image data D2 includes B-mode image data BD2 and display elastic image data ED2d. The ultrasonic image data D3 includes B-mode image data BD3 and display elastic image data ED3d, and the ultrasonic image data D4 includes B-mode image data BD4 and display elastic image data ED4d. Further, the ultrasonic image data D5 includes B-mode image data BD5 and display elastic image data ED5d.

  In the frames F2 to F5, the data obtained by the elastic image data creation unit 52 is assumed to be elastic image data ED2, ED3, ED4, ED5. Here, the elasticity image data obtained by the elasticity image data creation unit 52 is not displayed as the elasticity image EG as it is, but elasticity based on the data obtained by weighted addition with the data of the elasticity image displayed immediately before. An image EG is displayed. Thereby, an elastic image in consideration of past frames is displayed. Therefore, here, the displayed elasticity image data is used as display elasticity image data, and is distinguished from the elasticity image data obtained by the elasticity image data creation unit 52.

More specifically, the elastic image EG displayed in the frame F2 is an image based on the display elastic image data ED2d. The display elasticity image data ED2d is data obtained by weighted addition of the elasticity image data ED2 obtained by the elasticity image data creation unit 52 and the display elasticity image data ED1d in the immediately preceding frame F1 in the frame F2. . That is, the display elasticity image data ED2d is created based on the following (Formula 2).
ED2d = k × ED2 + (1-k) ED1d (Equation 2)
However, 0 <k <1.

The elastic image EG displayed in the frame F3 is an image based on the display elastic image data ED3d. This display elasticity image data ED3d is created based on the following (formula 3).
ED3d = k × ED3 + (1-k) ED2d (Equation 3)

That is, for a frame that is not an error frame, display elastic image data EDmd is created based on (Equation 4) below.
EDmd = k * EDm + (1-k) ED (m-1) d (Formula 4)
Here, in (Expression 4), m is a natural number representing a frame number.

Next, the frame F4 will be described. If the above (Formula 4) is also used for the frame F4, the display elastic image data ED4d ′ is created based on the following (Formula 5).
ED4d ′ = k × ED4 + (1-k) ED3d (Formula 5)

However, the frame F4 is an error frame, and the display elasticity image data ED4d ′ obtained from the (formula 5) includes the elasticity image data ED4 that does not accurately reflect the elasticity of the living tissue. The elastic image EG based on the image data ED4d ′ is an image with low quality. Therefore, for the frame F4 that is an error frame, display elastic image data ED4d is created based on (Equation 6) below, and an elastic image EG based on the display elastic image data ED4d is displayed.
ED4d = k × ED3 + (1-k) ED3d (Expression 6)

  Accordingly, an elastic image EG based on the display elastic image data ED4d is displayed instead of the elastic image EG based on the display elastic image data ED4d ′. The elastic image EG based on the display elastic image data ED4d ′ is an example of an embodiment of the error frame elastic image EG in the present invention. The elastic image EG based on the display elastic image data ED4d is an example of an embodiment of a predetermined alternative elastic image in the present invention.

Similarly, for the frame F5 that is an error frame, display elastic image data ED5d is created based on the following (Equation 7), and an elastic image EG based on the display elastic image data ED5d is displayed.
ED5d = k × ED3 + (1-k) ED4d (Expression 7)

  The elastic image EG based on the display elastic image data ED5 obtained from (Equation 7) is an example of an embodiment of a predetermined alternative elastic image in the present invention.

That is, for the error frame, the display elasticity image data EDmd is created based on (Equation 8) below.
EDmd = k × EDz + (1−k) ED (m−1) d (Equation 8)
In (Equation 8), z is a natural number representing the frame number.

  Here, in (Equation 8), EDz is elastic image data obtained by the elastic image data creation unit 52 in the latest frame that is not an error frame. The display elasticity image data ED (m−1) d is elasticity image data displayed in the immediately preceding frame, and weighted addition of the elasticity image data of the past several frames not including the elasticity image data of the error frame. Data obtained by processing.

  As described above, since the display elastic image data is created without including the error frame elastic image data, the quality of the elastic image EG can be maintained.

  In the case of an error frame, as shown in (Equation 8), the display elastic image data ED (m−1) d of the immediately previous frame and the elastic image data EDz of the latest frame that is not an error frame (in this example, Elastic image EG based on display elastic image data obtained by weighted addition with elastic image data ED3) is displayed. Therefore, even when error frames are continuous, display elastic image data EDmd is obtained so that the ratio of the elastic image data of the latest frame that is not an error frame increases little by little, and the display as if the elastic image EG is frozen. Can be prevented.

  Incidentally, in the creation of the alternative elastic image by the method described in FIG. 11, the weighted addition process is performed at the stage of the elastic image data, but the weighted addition process is performed at the stage of the elastic data obtained by the physical quantity calculation unit 51. You may do it.

  Next, a second modification will be described. As shown in FIG. 12, the ultrasonic diagnostic apparatus 1 ′ of the second modification includes a quality display creation unit 12. The quality display creating unit 12 receives the calculated value Y of the ratio calculating unit 9. Then, the quality display creation unit 12 plots the calculated value Y for each frame as the quality value Qn of the elastic image EG, and the quality display QG includes a graph gr in which the horizontal axis represents time and the vertical axis represents the quality value Qn. (See FIG. 13). At this time, the quality display creation unit 12 may calculate an average of the quality value Qn for a plurality of frames and plot the average value. Thereby, it is possible to obtain a stable graph gr with no variation in numerical values.

  The quality display QG created by the quality display creation unit 12 is combined with the ultrasonic image G in the display control unit 6. Accordingly, the quality display QG is displayed on the display unit 7 below the ultrasonic image G. The said display part 7 is an example of embodiment of the alerting | reporting part in this invention.

  The quality display QG will be described in more detail. When the ultrasound image G is displayed as a moving image, the quality display creation unit 12 plots the quality value Qn in the currently displayed ultrasound image G for each frame. By doing so, the graph gr is created. Accordingly, the graph gr is displayed on the display unit 7 so as to flow from left to right as time passes, as shown in FIGS.

  However, for example, when the ultrasound image G is a moving image created based on data stored in the storage unit (not shown), the quality display creation unit 10 displays the graph gr from the beginning to the end of reproduction. May be created and displayed on the display unit 7. In this case, as shown in FIG. 17, in addition to the graph gr, the quality display QG includes a vertical line segment b indicating which time frame the currently displayed ultrasonic image G belongs to. May be included. This line segment b moves from left to right during reproduction of the ultrasonic image G (in the direction of the arrow in the figure).

  Incidentally, the length of the line segment b is a length between the minimum value and the maximum value of the quality value Qn calculated for each frame.

According to the second modified example, the quality display QG including the graph gr representing the temporal change of the quality value Qn calculated based on the ratio Ra of the average value Xr _AV to the ideal value Xi _AV is displayed. The operator can easily determine whether or not the ultrasonic probe 2 is insufficient or excessively pressed against the living tissue.

  The operator may freeze the ultrasonic image G at a place where the quality value Qn is high by looking at the graph gr, and output the ultrasonic image G by printing or the like. Thereby, an ultrasonic image that more accurately reflects the elasticity of the living tissue can be output by printing or the like. Further, when the ultrasonic image G is displayed in real time, the operator can adjust the degree of the compression and relaxation of the ultrasonic probe 2 on the living tissue by looking at the graph gr.

Incidentally, the quality display QG may be displayed when an alternative elastic image is displayed in the first modification. In this way, when a calculated value Y quality value Qn is less than the threshold value Y _TH is elastic image EG displayed on the display unit 7 can recognize that an alternative elastic image.

Next, a third modification will be described. In the third modified example, the physical quantity averaging unit 8 selects a correlation window in which a correlation calculation having a correlation coefficient C (0 ≦ C ≦ 1) equal to or greater than a predetermined threshold _CTH is performed, and an average of the displacements is selected. Calculation is performed to obtain an average value Xr _AV ′. Then, the ratio calculation unit 9 calculates the ratio Ra using the average value Xr _AV ′, and calculates Y using (Equation 1). Furthermore, the quality display creation unit 12 may create the quality display QG using the calculated value Y.

The average value Xr _AV ′ is an average value obtained by removing the displacement of a portion having a low correlation coefficient, such as a portion where the intensity of the echo signal is insufficient or a portion where the lateral displacement of the living tissue occurs. If, in the case of performing the calculation of the average value Xr _AV including a displacement obtained by the low correlation calculation correlation coefficient, the degree of compression and its relaxation to a living body tissue by the ultrasonic probe 2 is a suitable also, for example, when the intensity of the echo signal is weak, the average value Xr _AV is small, the calculated value Y may be decreased. Therefore, as in the third modification, the calculated value Y obtained by using the average value calculated excluding the displacement of the portion having a low correlation coefficient is obtained by compressing the living tissue with the ultrasonic probe 2. If the degree of relaxation is appropriate, the value is close to 1. As described above, according to the third modified example, if the ultrasound probe 2 is compressed and relaxed with a suitable strength, the calculated value Y may exceed the threshold value _YTH . Becomes higher. Therefore, it is possible to prevent the elastic image EG from being displayed even though the ultrasound probe 2 is compressed and relaxed with an appropriate strength. In addition, the operator can adjust the strength of the compression by the ultrasonic probe 2 and its relaxation depending on whether or not the elastic image EG is displayed.

(Second embodiment)
Next, 2nd embodiment is described based on FIG.18 and FIG.19. In addition, about the structure same as 1st embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The ultrasonic diagnostic apparatus 20 of this example does not include the physical quantity average unit 8 and the ratio calculation unit 9 but includes a correlation coefficient average unit 21 instead. The correlation coefficient average unit 21 is an example of an embodiment of the correlation coefficient average unit 21 in the present invention.

  The operation of the ultrasonic diagnostic apparatus 20 of this example will be described. In this example, the correlation coefficient averaging unit 21 calculates the average value Cav in the region of interest R (regions R (i), R (ii)) of the correlation coefficient C in each correlation calculation performed by the physical quantity calculation unit 51. Is calculated for each frame. Here, since 0 ≦ C ≦ 1, 0 ≦ Cav ≦ 1. As the correlation coefficient in the correlation calculation is closer to 1, a displacement that more accurately reflects the elasticity of the living tissue can be obtained. On the other hand, as the correlation coefficient is closer to zero, a displacement that more accurately reflects the elasticity of the living tissue can be obtained. Disappear. Accordingly, the quality of the elastic image EG becomes better as the average value Cav approaches 1 while the quality of the elastic image EG becomes worse as the average value Cav approaches zero.

The average value Cav is input to the display control unit 6. The display control unit 6 determines the average value Cav is equal to or less than the threshold Cav _TH frame as an error frame does not satisfy the predetermined criteria, not displaying the elastic image EG.

As with the threshold value Y _TH of the first embodiment, the threshold value Cav _TH displays an elastic image EG that accurately reflects the elasticity of the living tissue to some degree so that the frame rate does not decrease too much. Set to a possible value. The threshold value Cav _TH may be stored in advance in a storage unit (not shown) or may be set by inputting in the operation unit 11.

According to the ultrasonic diagnostic apparatus 20 of the present example, since the elastic image EG of the error frame in which the average value Cav of the correlation coefficient C is equal to or less than the threshold Cav _TH is not displayed, the compression on the living tissue and the relaxation thereof are excessive. The elastic image EG created based on the displacement obtained by the correlation calculation with a low correlation coefficient due to the intensity of the echo signal being insufficient or the like is not displayed. Therefore, since only the high-quality elastic image EG can be displayed, the elasticity of the living tissue can be accurately grasped.

Next, a modification of the second embodiment will be described. As shown in FIG. 20, the ultrasonic diagnostic apparatus 20 ′ of this modification has a quality display creation unit 22 as in the second modification of the first embodiment. The Quality display creating unit 22 plots the average value C _AV as the quality value Qn, to create a quality display QG comprising the graph gr. At this time, the quality display creating unit 22 may calculate an average of a plurality of frames of the quality value Qn and plot the average value. The quality display creation unit 22 is an example of an embodiment of a notification unit in the present invention.

  Also in this example, the graph gr constituting the quality display QG may be displayed so as to flow from left to right as time passes, as in the first embodiment. The quality display QG may include a vertical line segment b in addition to the graph gr.

According to this modification, the quality indication QG is displayed consisting graph gr representing the time variation of the average value C _AV of the correlation coefficient C Quality value Qn, the operator, the elastic image displayed For example, it was created based on the displacement obtained by the correlation calculation with a low correlation coefficient due to excessive compression and relaxation of the living tissue or insufficient intensity of the echo signal. It is possible to grasp whether the image is elastic image data.

(Third embodiment)
Next, 3rd embodiment is described based on FIG.21 and FIG.22. In addition, about the structure same as 1st, 2nd embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The ultrasonic diagnostic apparatus 30 of this example includes the physical quantity average unit 8, the ratio calculation unit 9, the correlation coefficient average unit 21, and the like, and further includes a multiplication unit 31. The multiplication unit 31 is an example of an embodiment of a multiplication unit in the present invention.

The operation of the ultrasonic diagnostic apparatus 30 of this example will be described. Also in this example, the physical quantity averaging unit 8 selects the correlation window in which the correlation calculation with the correlation coefficient C equal to or greater than the predetermined threshold C _TH is performed, as in the third modification of the first embodiment. An average value Xr _AV ′ of the displacement is calculated, and the ratio calculation unit 9 calculates the ratio Ra using the average value Xr _AV ′, and calculates Y from the (Equation 1). Further, as in the second embodiment, the correlation coefficient averaging unit 21 calculates the average value Cav of the correlation coefficient C.

  Then, the multiplication unit 31 multiplies the calculated value Y obtained by the ratio calculation unit 9 and the average value Cav of the correlation coefficient C obtained by the correlation coefficient average unit 21 to obtain a multiplication value M. calculate. This multiplication value M is calculated for each frame.

  Here, when multiplying the calculated value Y and the average value Cav of the correlation coefficient C, the multiplication unit 31 may multiply by weighting.

  Here, since 0 ≦ Y ≦ 1 and 0 ≦ Cav ≦ 1, 0 ≦ M ≦ 1. Since the multiplication value M is a multiplication value of the calculated value Y and the average value Cav of the correlation coefficient C, the quality of the elastic image EG becomes better as the multiplication value M approaches 1, while the multiplication value M As M approaches zero, the quality of the elastic image EG becomes worse.

The multiplication value M is input to the display control unit 6. The display control unit 6 determines that a frame in which the multiplication value M is equal to or less than the threshold value M _TH is an error frame that does not satisfy a predetermined criterion, and does not display the elastic image EG.

The threshold value M _TH is the same as the threshold value Y _TH and the threshold value Cav _{TH of} the first and second embodiments, and the frame rate of the elasticity image EG that accurately reflects the elasticity of the living tissue to some extent is too low. It is set to a value that can be displayed so that there is no. The threshold value M _TH may be stored in advance in a storage unit (not shown), or may be set by inputting in the operation unit 11.

Here, as in the third modification of the first embodiment, based only on the calculated value Y calculated from the average value Xr _AV ′ of the displacement obtained by the correlation calculation of the correlation coefficient equal to or greater than the predetermined threshold C _TH. If it is determined whether or not to display the elastic image EG, the correlation coefficient is not reflected as an element for evaluating the quality of the elastic image. On the other hand, when it is determined whether or not to display the elastic image EG based only on the average value Cav of the correlation coefficient C as in the second embodiment, the ultrasound probe 2 compresses and relaxes the living tissue. Even if the degree of is insufficient, since the correlation coefficient C is high, the average value Cav may be high and the elastic image EG may be displayed. However, in this example, the multiplication value M obtained by multiplying the calculated value Y obtained by using the ratio Ra calculated by using the average value Xr _AV ′ and the average value Cav of the correlation coefficient C. Is a combination of an element of the degree of compression and relaxation on a living tissue and an element of a correlation coefficient. Therefore, by determining whether or not to display the elastic image EG based on the multiplication value M, it is possible to more appropriately determine whether or not the quality of the elastic image EG is high.

  Next, a modification of the third embodiment will be described. As shown in FIG. 23, the ultrasonic diagnostic apparatus 30 ′ of this modification has a quality display creation unit 32. The quality display creation unit 32 plots the multiplication value M as the quality value Qn to create the quality display QG. At this time, the quality display creation unit 32 may calculate an average of a plurality of frames of the quality value Qn and plot the average value.

  Also in this example, the graph gr constituting the quality display QG may be displayed so as to flow from left to right as time passes. The quality display QG may include a vertical line segment b in addition to the graph gr.

  According to this modification, the quality display QG obtained by plotting the multiplication value M obtained by multiplying the calculated value Y and the average value Cav of the correlation coefficient C as the quality value Qn is displayed. Whether or not the image is EG can be evaluated from a wider viewpoint than before.

(Fourth embodiment)
Next, 4th embodiment is described based on FIG.24 and FIG.25. In addition, about the structure same as 1st-3rd embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The ultrasonic diagnostic apparatus 40 of this example has the same basic configuration as the ultrasonic diagnostic apparatus 30 of the third embodiment, but the calculated value Y obtained by the ratio calculation unit 9 and the correlation coefficient averaging unit 21 are the same. An error frame is determined using a selected one of the obtained correlation coefficient average value Cav and the multiplication value M obtained by the multiplication unit 31.

Specifically, in the operation unit 11, an operator inputs which of the calculated value Y, the average value Cav of the correlation coefficient C, and the multiplication value M is used to determine the error frame. The Then, based on the instruction input in the operation unit 11, the control unit 10 controls to calculate the calculated value Y by the ratio calculating unit 9 and the average value of the correlation coefficient C by the correlation coefficient averaging unit 21. Either the calculation of Cav or the multiplication value M by the multiplication unit 31 is performed. The display control unit 6 determines an error frame based on the obtained value. Specifically, if the calculated value Y is selected, the display control unit 6 judges the frame the calculated value Y is equal to or less than the threshold Y _TH as an error frame. Also, if the average value Cav is selected, the display control unit 6 determines the average value Cav is equal to or less than the threshold Cav _TH frame as an error frame. Further, when the multiplication value M is selected, the display control unit 6 determines that a frame in which the multiplication value M is equal to or less than the threshold value _MTH is an error frame.

  The operator may change the type of the value once selected from the calculated value Y, the average value Cav of the correlation coefficient C, and the multiplication value M by inputting instructions from the operation unit 11. As described above, when the switching instruction is input by the operation unit 11, the error frame is determined using the newly selected type of value.

  According to the ultrasonic diagnostic apparatus 40 of this example, only the elasticity image reflecting the elasticity of the living tissue can be displayed more accurately as in the above embodiments, and the ratio calculation unit can be used for determining the error frame. Since the calculated value Y obtained in 9, the average value Cav of the correlation coefficient C obtained in the correlation coefficient averaging unit 21, and the multiplication value M obtained in the multiplication unit 31 can be selected, it corresponds to an error frame. It is possible to determine whether or not an elastic image EG with higher quality can be displayed.

  Next, a modification of the fourth embodiment will be described. As shown in FIG. 26, the ultrasonic diagnostic apparatus 40 ′ of this modification has a quality display creation unit 41. When any one of the calculated value Y, the average value Cav of the correlation coefficient C and the multiplication value M is selected as the quality value Qn, the quality display creating unit 41 creates a quality display QG using the selected quality value Qn. To do. When the quality value Qn selected is changed, a quality display QG is created based on the changed quality value Qn.

According to this modification, the calculated value quality display QG created with Y, quality display QG created using the average value C _AV of the correlation coefficient C, was created using the multiplication value M Since the quality display QG can be switched and displayed, it can be evaluated from a wide viewpoint whether the image is an elastic image accurately reflecting the elasticity of the living tissue.

(Fifth embodiment)
Next, a fifth embodiment will be described with reference to FIG. In addition, about the structure same as 1st-4th embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The ultrasonic diagnostic apparatus 50 of this example includes a physical quantity average unit 8, a ratio calculation unit 9, and a correlation coefficient average unit 21. The calculated value Y obtained by the ratio calculating unit 9 and the average value Cav of the correlation coefficient C obtained by the correlation coefficient averaging unit 21 are input to the display control unit 6.

The display control unit 6 does not display an elastic image EG of an error frame that is determined not to satisfy a predetermined criterion based on the calculated value Y and the average value Cav of the correlation coefficient C. Specifically, the display control unit 6 satisfies the case where one of the condition that the calculated value Y is equal to or less than the threshold value Y _TH and the condition that the average value Cav is equal to or less than the threshold value Cav _TH is satisfied. Then, it is determined that the error frame does not satisfy the predetermined criterion, and the elasticity image EG is not displayed.

According to the ultrasonic diagnostic apparatus 50 of the present embodiment, among the calculated values Y and the average value Cav, not more than one even one threshold Y _TH or threshold Cav _TH, since the elastic image EG not displayed, quality higher The display of only the elastic image EG can be made more reliable.

  Also in this example, the quality display QG may be displayed. In this case, either the calculated value Y or the average value Cav may be used as the quality value Qn, or the multiplication value M obtained by multiplying the calculated value Y and the average value Cav may be used as the quality value Qn.

(Sixth embodiment)
Next, a sixth embodiment will be described with reference to FIGS. In addition, about the structure same as 1st-5th embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The ultrasonic diagnostic apparatus 60 of this example does not include the physical quantity average unit 8, the ratio calculation unit 9, the correlation coefficient average unit 21, and the multiplication unit 31, and the display control unit 6 includes the physical quantity calculation unit 51. The displacement calculated with a positive / negative sign for each pixel is also input.

The display control unit 6 does not display the elastic image EG of the error frame that is determined not to satisfy the predetermined criterion based on the ratio of the positive / negative sign of the displacement in one frame. Specifically, the display control unit 6 first obtains positive and negative numbers for the displacement calculated for each pixel in one frame in the physical quantity calculation unit 51. If either one of the following conditions (Equation 9) or (Equation 10) is satisfied, the elastic image EG of the frame is displayed. On the other hand, when neither of the conditions of (Expression 9) and (Expression 10) is satisfied, it is determined that the frame is an error frame, and the elastic image EG is not displayed.
Positive number> n × negative number (Equation 9)
Negative number> n × positive number (Equation 10)
However, in (Expression 9) and (Expression 10), n ≧ 1.

  Here, the relationship between the ratio of the positive / negative sign of the displacement in one frame and the quality of the elastic image EG will be described. For example, if the compression by the ultrasonic probe 2 and its relaxation are appropriately performed, the rate of the sign of the displacement in one frame will be large. However, in the case where the direction of compression and relaxation by the ultrasonic probe 2 is not appropriate and lateral displacement or the like occurs in the living tissue, the rate of the displacement sign in one frame is either positive or negative However, the ratios of both codes are antagonized. Therefore, when neither of the conditions of (Equation 9) and (Equation 10) is satisfied, the ratio of the positive and negative signs is competitive, so that the frame is determined to be an error frame. .

  N in (Expression 9) and (Expression 10) is input and set in the operation unit 11. Then, with this n, it is possible to set the ratio of positive and negative signs as a reference for determining whether or not to make an error frame. As the value of n is increased, an error frame is determined even if the ratio of one of the positive and negative signs is large, and the frame rate may decrease. Quality can be maintained. On the other hand, as the value of n decreases, even if the difference in the sign ratios between the two decreases, the frame is not determined as an error frame. Therefore, the frame rate can be maintained, but the quality of the displayed elastic image EG is improved. May decrease. Therefore, n is set in consideration of the quality of the elastic image and the frame rate. For example, n is appropriately set in the range of 1 ≦ n ≦ 2.

  According to the ultrasonic diagnostic apparatus 60 of the present example, for example, an elastic image EG that is created based on an echo signal acquired in a situation where the direction of compression and relaxation by the ultrasonic probe 2 is not appropriate is not displayed. . Therefore, it is possible to display only the elasticity image that more accurately reflects the elasticity of the living tissue.

  As mentioned above, although this invention was demonstrated by each said embodiment, of course, this invention can be variously implemented in the range which does not change the main point. For example, in the second embodiment to the sixth embodiment, as in the first modification of the first embodiment, a complementary process for displaying an alternative elastic image instead of the elastic image EG of the error frame may be performed. .

  Further, the ratio calculation unit 9 may calculate only the ratio Ra and not perform the calculation of (Equation 1). In this case, the display control unit 6 sets a frame that does not satisfy the predetermined criterion based on the ratio Ra as an error frame, and does not display the elastic image EG. When the quality display creating unit 12 shown in the second modification of the first embodiment is provided, the quality display creating unit 12 displays a graph gr obtained by plotting the ratio | Ra | as the quality value Qn. The quality display QG may be created.

  An example of the quality display QG created by plotting the ratio | Ra | as the quality value Qn and displayed on the display unit 7 is shown in FIG. In FIG. 30, the horizontal axis represents time, and the vertical axis represents the ratio | Ra |. As shown in FIG. 30, a band-shaped portion O may be displayed in the range of a ≦ | Ra | ≦ b. This band-like portion O is set in a range including | Ra | = 1, that is, a range satisfying a <1, b> 1, and a ratio | Ra | in which an elastic image EG having good quality is obtained. Is done. By displaying such a band-shaped portion O, if the operator performs compression and relaxation on the living tissue with the ultrasonic probe 2 so that the quality display QG enters this band-shaped portion O, An elasticity image that accurately reflects elasticity can be obtained.

  When a ≦ | Ra | ≦ b, the display control unit 6 displays the elastic image EG of the frame. On the other hand, if | Ra | <a or |Ra|> b, the display control unit 6 determines that the frame is an error frame that does not satisfy a predetermined criterion, and displays the elastic image EG. I won't let you.

  Further, the quality display QG is not limited to the one composed of the graph gr, and may be composed of a bar B as shown in FIG. The bar B has a length in the vertical direction corresponding to the quality value Qn (0 ≦ Qn ≦ 1), and expands and contracts in the vertical direction as the quality value Qn changes.

  Further, the bar B does not expand and contract in the vertical direction according to the quality value Qn, but may change in color according to the quality value Qn.

  In addition, the quality display QG may be displayed numerically on the display unit 7. Furthermore, the quality value Qn is not limited to being displayed as the quality display QG. For example, a speaker (not shown) for emitting the quality value Qn as sound may be provided. This speaker is an example of an embodiment of a notification unit in the present invention. In this case, the level of the quality value Qn is expressed by the level of the sound.

  In addition, the physical quantity calculation unit 51 may calculate strain or elastic modulus of the living tissue instead of displacement due to deformation of the living tissue as a physical quantity related to the elasticity of the living tissue.

1, 1 ', 20, 20', 30, 30 ', 40, 40', 50, 60 Ultrasound diagnostic apparatus 6 Display control unit 7 Display unit 8 Physical quantity average unit 9 Ratio calculation unit (comparison unit)
12 Operation Unit 21 Correlation Coefficient Average Unit 31 Multiplication Unit 51 Physical Quantity Calculation Unit 52 Elastic Image Data Creation Unit

Claims (21)

A correlation window is set for two temporally different echo signals on the same acoustic line obtained by transmitting and receiving ultrasonic waves to and from a living tissue, and a correlation calculation is performed between the correlation windows to calculate a physical quantity related to the elasticity of each part in the living tissue. A physical quantity calculating unit to
Based on the physical quantity, an elastic image data creation unit for creating elastic image data of a living tissue for an elastic image creation region on an ultrasonic transmission / reception surface;
A display unit for displaying an elastic image based on the elastic image data;
A display control unit for controlling display of an elastic image on the display unit;
A physical quantity average unit for calculating an average of the physical quantities in the elastic image creation region for each frame;
A comparison unit that compares the calculated value of the physical quantity average unit with a preset average value of the physical quantity,
The ultrasonic diagnostic apparatus, wherein the display control unit does not display an elastic image of an error frame that is determined not to satisfy a predetermined criterion based on a comparison result by the comparison unit.   The ultrasonic diagnostic apparatus according to claim 1, wherein the physical quantity averaging unit performs an average calculation of physical quantities obtained for a correlation window in which a correlation calculation of a correlation coefficient equal to or greater than a predetermined threshold is performed.   The ultrasonic diagnostic apparatus according to claim 1, wherein the comparison unit calculates a ratio of a calculated value by the physical quantity average unit to a preset average value of the physical quantity as the comparison result.   The ultrasonic diagnostic apparatus according to claim 1, further comprising a notification unit that notifies a comparison result by the comparison unit. A correlation window is set for two temporally different echo signals on the same acoustic line obtained by transmitting and receiving ultrasonic waves to and from a living tissue, and a correlation calculation is performed between the correlation windows to calculate a physical quantity related to the elasticity of each part in the living tissue. A physical quantity calculating unit to
Based on the physical quantity, an elastic image data creation unit for creating elastic image data of a living tissue for an elastic image creation region on an ultrasonic transmission / reception surface;
A display unit for displaying an elastic image based on the elastic image data;
A display control unit for controlling display of an elastic image on the display unit;
A correlation coefficient average unit that calculates the average of the correlation coefficient in the elastic image creation region in the correlation calculation between the correlation windows for each frame, and
The ultrasonic diagnostic apparatus, wherein the display control unit does not display an elastic image of an error frame that is determined not to satisfy a predetermined criterion based on a calculation result of the correlation coefficient averaging unit.   The ultrasonic diagnostic apparatus according to claim 5, further comprising a notification unit that notifies a calculation result by the correlation coefficient averaging unit. A correlation window is set for two temporally different echo signals on the same acoustic line obtained by transmitting and receiving ultrasonic waves to and from a living tissue, and a correlation calculation is performed between the correlation windows to calculate a physical quantity related to the elasticity of each part in the living tissue. A physical quantity calculating unit to
Based on the physical quantity, an elastic image data creation unit for creating elastic image data of a living tissue for an elastic image creation region on an ultrasonic transmission / reception surface;
A display unit for displaying an elastic image based on the elastic image data;
A display control unit for controlling display of an elastic image on the display unit;
A physical quantity averaging unit that calculates an average of the physical quantity obtained for the correlation window in which the correlation calculation of the correlation coefficient equal to or greater than a predetermined threshold is performed in the elastic image creation region for each frame;
A ratio calculating unit that calculates a ratio of a calculated value by the physical quantity average unit to a preset average value of the physical quantities;
A correlation coefficient average unit that calculates an average of the correlation coefficient in the elastic image creation region in the correlation calculation between the correlation windows for each frame;
A multiplying unit that multiplies the calculated value of the ratio calculating unit by the calculated value of the correlation coefficient averaging unit;
The ultrasonic diagnostic apparatus, wherein the display control unit does not display an elastic image of an error frame that is determined not to satisfy a predetermined criterion based on a calculation result of the multiplication unit.   The ultrasonic diagnostic apparatus according to claim 7, wherein the multiplication unit performs a weighting operation on a calculated value of the ratio calculating unit and a calculated value of the correlation coefficient average unit.   The ultrasonic diagnostic apparatus according to claim 7, further comprising a notification unit that notifies a multiplication result by the multiplication unit. A correlation window is set for two temporally different echo signals on the same acoustic line obtained by transmitting and receiving ultrasonic waves to and from a living tissue, and a correlation calculation is performed between the correlation windows to calculate a physical quantity related to the elasticity of each part in the living tissue. A physical quantity calculating unit to
Based on the physical quantity, an elastic image data creation unit for creating elastic image data of a living tissue for an elastic image creation region on an ultrasonic transmission / reception surface;
A display unit for displaying an elastic image based on the elastic image data;
A display control unit for controlling display of an elastic image on the display unit;
A physical quantity averaging unit that calculates an average of the physical quantity obtained for the correlation window in which the correlation calculation of the correlation coefficient equal to or greater than a predetermined threshold is performed in the elastic image creation region for each frame;
A ratio calculating unit that calculates a ratio of a calculated value by the physical quantity average unit to a preset average value of the physical quantities;
A correlation coefficient average unit that calculates an average of the correlation coefficient in the elastic image creation region in the correlation calculation between the correlation windows for each frame;
A multiplier for multiplying the calculated value of the ratio calculating unit by the calculated value of the correlation coefficient average unit;
An operation unit for inputting an instruction to select one of a calculation result of the ratio calculation unit, a calculation result of the correlation coefficient average unit, or a calculation result of the multiplication unit;
The ultrasonic diagnostic apparatus, wherein the display control unit does not display an elastic image of an error frame determined not to satisfy a predetermined criterion based on a calculation result selected by the operation unit.   The information processing apparatus according to claim 1, further comprising: a notification unit that notifies a calculation result selected by the operation unit among the calculation result of the ratio calculation unit, the calculation result of the correlation coefficient averaging unit, or the calculation result of the multiplication unit. The ultrasonic diagnostic apparatus according to 10. A correlation window is set for two temporally different echo signals on the same acoustic line obtained by transmitting and receiving ultrasonic waves to and from a living tissue, and a correlation calculation is performed between the correlation windows to calculate a physical quantity related to the elasticity of each part in the living tissue. A physical quantity calculating unit to
Based on the physical quantity, an elastic image data creation unit for creating elastic image data of a living tissue for an elastic image creation region on an ultrasonic transmission / reception surface;
A display unit for displaying an elastic image based on the elastic image data;
A display control unit for controlling display of an elastic image on the display unit;
A physical quantity averaging unit that calculates an average of the physical quantity obtained for the correlation window in which the correlation calculation of the correlation coefficient equal to or greater than a predetermined threshold is performed in the elastic image creation region for each frame;
A ratio calculating unit that calculates a ratio of a calculated value by the physical quantity average unit to a preset average value of the physical quantities;
A correlation coefficient average unit that calculates the average of the correlation coefficient in the elastic image creation region in the correlation calculation between the correlation windows for each frame, and
The display control unit does not display an elastic image of an error frame that is determined not to satisfy a predetermined criterion based on a calculation result of the ratio calculation unit and a calculation result of the correlation coefficient average unit. Ultrasonic diagnostic equipment.   The ultrasonic diagnostic apparatus according to claim 12, further comprising a notification unit that notifies either the calculation result of the ratio calculation unit or the calculation result of the correlation coefficient average unit. A multiplier for multiplying the calculated value of the ratio calculating unit by the calculated value of the correlation coefficient average unit;
A notification unit for reporting the calculation result of the multiplication unit;
The ultrasonic diagnostic apparatus according to claim 12, comprising: A correlation window is set for two echo signals different in time on the same sound line obtained by transmitting and receiving ultrasonic waves while performing compression and relaxation on the biological tissue, and performing a correlation calculation between the correlation windows, A physical quantity calculating unit that calculates a physical quantity related to elasticity of each part in the tissue with a positive and negative sign corresponding to the compression and relaxation thereof;
Based on the physical quantity, an elastic image data creation unit for creating elastic image data of a living tissue for an elastic image creation region on an ultrasonic transmission / reception surface;
A display unit for displaying an elastic image based on the elastic image data;
A display control unit for controlling display of an elastic image on the display unit;
The ultrasonic diagnostic apparatus, wherein the display control unit does not display an elastic image of an error frame that is determined not to satisfy a predetermined criterion based on a ratio of the positive and negative signs in one frame. A correlation window is set for two temporally different echo signals on the same acoustic line obtained by transmitting and receiving ultrasonic waves to and from a living tissue, and a correlation calculation is performed between the correlation windows to calculate a physical quantity related to the elasticity of each part in the living tissue. A physical quantity calculating unit to
Based on the physical quantity, an elastic image data creation unit for creating elastic image data of a living tissue for an elastic image creation region on an ultrasonic transmission / reception surface;
A display unit that displays an elasticity image based on the elasticity image data; and a display control unit that controls display of the elasticity image on the display unit;
The ultrasonic diagnostic apparatus, wherein the display control unit displays a predetermined alternative elastic image instead of an elastic image of an error frame determined not to satisfy a predetermined criterion.   The ultrasonic diagnostic apparatus according to claim 16, wherein the alternative elastic image is an elastic image created by weighting and adding elastic image data for several frames before the error frame.   The alternative elastic image is an elastic image created by weighting and adding the elastic image data displayed immediately before and the elastic image data of the latest frame that is not the error frame. The ultrasonic diagnostic apparatus according to 16.   17. The elastic image data displayed immediately before is data obtained by weighting and adding elastic image data of several past frames not including error image elastic image data. The ultrasonic diagnostic apparatus as described.   The ultrasonic diagnosis according to claim 16, wherein the alternative elastic image is an elastic image created by weighting and adding elastic image data of the error frame and elastic image data before the error frame. apparatus.   The ultrasonic diagnostic apparatus according to claim 16, wherein the alternative elastic image is an elastic image of a frame displayed immediately before the error frame.

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